JVHC Journal of Veterinary Healthcare 2575-1212 Open Access Pub United States JVHC-20-3225 10.14302/issn.2575-1212.jvhc-20-3225 research-article Observations and analysis of risk factors for GDV in a single institution: a case-control study Fabrizio di Virgilio 1 * Emanuela Rabaioli 2 Massimo Gualtieri 3 Luca Formaggini 4 Clinique Vétérinaire VET24; 994 Avenue de la Republique, 59700 Marcq-en-Baroeul - France. DVM - Doctor in veterinary medicine. Clinica Veterinaria Lago Maggiore: Corso Camillo Benso Cavour, 3, 28040 Dormelletto NO, DVM - Doctor in veterinary medicine. Department of Health, Animal Science and Food Safety, Faculty of Veterinary Medicine, University of Milan, Milan, Italy, DVM - Doctor in veterinary medicine. Clinica Veterinaria Lago Maggiore: Corso Camillo Benso Cavour, 3, 28040 Dormelletto NO, DVM - Doctor in veterinary medicine. corresponding author Mohammed Elmetwally 1 Assistant Prof of Theriogenology, Egypt. Fabrizio di Virgilio, Clinique Vétérinaire VET24; 994 Avenue de la Republique, 59700 Marcq-en-Baroeul - France, Email: dvm_fabrizio_divirgilio@yahoo.it

The authors have declared that no competing interests exist.

 09 03 2020 2 1 16 40 19 02 2020 06 03 2020 09 03 2020 © 2020 Fabrizio di Virgilio, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://openaccesspub.org/jvhc/article/1276 Objective

To evaluate/ determine the risk factors for dogs presented with Gastric Dilation- Volvulus (GDV) to a referral veterinary centre and to compare the results with those currently reported in veterinary literature.

 Materials and Methods

The observational case-control study comprised a population of 215 dogs that attended the referral centre between 2000 and 2018. Medical records were searched for GDV and those matching the criteria were manually reviewed. A questionnaire was completed by the owners of the dogs involved in the study (both case and control populations) in order to gain further information that could be considered relevant to GDVs. In particular, information included the dogs’ behaviour and the dogs daily activities.

Results

The study included 115 cases of GDV and 115 controls. Out of the GDV dogs 13% (15/115) were small breed dogs and the remaining 87% (100/115) either large or giant breeds.

The following risk factors for developing a GDV have been identified: Purebred dogs over 3 years old and either large of giant breeds, weighing > 30 kg. Foreign body ingestion, diarrhoea, and grass consumption were also associated to increase the likelihood in developing GDV. Behavioural temperament was not associated with developing GDV.

 Clinical Significance

The findings support previously identified risk factors in the development of GDV, but characteristics related to the dogs temperament warrant further investigation. Knowledge of these results will further allow clinicians to make evidence‐based recommendations to owners in attempting to prevent GDV in dogs. Furthermore this paper confirms that the risk of GDV in certain breeds and in certain conditions is always high and that GDV is still an extremely current disease.

 Dog Gastric Dilatation-Volvulus Canine Gastroenteric Gastroenterology Stomach Epidemiologic Factors. Introduction

Gastric Dilatation - Volvulus (GDV) is an acute and potentially fatal syndrome that mainly affects large deep-chested dogs, although occasionally it has been reported in small dogs and other species, including cats1,2,3,4,5 guinea pigs7, monkeys8 and humans9 .Dilatation is supposed to precede torsion, though it has been reported that gastric torsion episodes may arise without prior dilatation9. Symptoms predominate due to rapid accumulation of gases and fluids within the gastric lumen leading to distension, increasing intraluminal pressure and stomach rotation; those in turn lead to dyspnoea, varying degrees of hypovolemic and/or septic shock, ventilation-perfusion mismatch, systemic inflammatory response syndrome (SIRS), coagulation malfunction and multiple organ dysfunction syndrome (MODS)10,11,12,13, including ventricular arrhythmias and Disseminated Intravascular Coagulation (DIC)14 . If left untreated, GDV can lead to severe impairment of venous return to the heart, diminished stroke volume, necrosis of the gastric wall and eventual fatality15.

Although the exact aetiology of GDV is still unknown, numerous predisposing risk factors have been described12,16. Male, large and giant pure breed dogs17,18, and deep chested dogs are at increased risk19. Other reported risk factors include increased age18, low Body Condition Score (BCS)17, nervous or a fearful temperament17, stressful events occurring within 8 hours prior to the GDV episode12, and a familial history of GDV18. Nutrition-related risk factors have also been identified, such as eating one meal per day, small food particles, rapid food ingestion17,20 and eating only one type of food14. Some authors have suggested a relationship between GDV and weather conditions with one study reporting a higher incidence during winter months21,whereas another reported an increase in environmental temperature presented as a significant risk factor for GDV16. The association between GDV and physical activity remains controversial15,16. Recently, a study on canine gut microbiome showed that microbiome in GDV patients was altered by an expansion of a minor lineage and was associated with specific alleles of both innate and adaptive immunity genes. These associations are consistent with the hypothesis that immune genes may play a role in predisposition to GDV by altering the gut microbiome22.

The purpose of this epidemiological survey was to determine whether some of the most commonly claimed risk factors for GDV exist in northern Italy and to ascertain whether there are differences when comparing similar studies conducted, to date, in other countries.

 Methods

The epidemiological case-control study was conducted at a single veterinary practice (between 2000 and 2018)

To meet the inclusion criteria dogs had to be older than 6 months of age, without previous prophylactic gastropexy. Dogs in the control group had never had a GDV episode. Owners of both GDV cases and control dogs should have completed and signed the questionnaire under direct supervision of the attending clinician.

All GDV dogs were recruited during their presentation to the centre for an acute episode of GDV. On the other hand, control dogs were selected randomly from patients brought into the centre for reasons other than GDV.

The questionnaire consisted of different sections including the owner's data, the dog’s signalment (breed, age, BCS, sex, neutered/intact), the dog’s temperament (shy, balanced, aggressive, or exuberant) as assigned by the owner. Two sections focused on the GDV and included treatments received, whether a previous episode had occurred, the time spent between physical activity and GDV presentation, the elapsed time between a meal and GDV, and the presence of a possible stressful situation before of the onset of the disease. The last part of the questionnaire included questions related to the dog's lifestyle and dietary habits. Both the owner and the veterinarian defined the BCS of the dog, choosing either skinny, thin, ideal weight, overweight, obese. Details of the physical activity performed by the dog during the day and correlation between physical activity and meal were documented. The owner was asked whether the dog was housed in kennels and whether it was used to long journeys. Finally the presence of vomiting/diarrhoea was investigated along with whether the dog was prone to ingesting grass or foreign bodies (Table 1).

Summary of distribution of individuals variables
DOG N° GDV BREED SEX AGE (Years) NEUTERED BODY WEIGHT KG ATTITUDE FOOD TYPE N° MEAL PER DAY FOOD AD LIBITUM INTAKE OF FOOD TYPE (SPEED) BOWEL POSITION BCS PHISICAL ACTIVITY FREQUENCY TIME (Hours) TIME IN BETWEEN PHYSICAL ACTIVITY AND MEAL LONG TRIPS FREQUENCY KENNEL VOMIT DIARRHEA EATING GRASS? EATING FOREIGHN BODIES? NOTE
1 Yes bernese mountain dog F 6 no 43 exuberant dry miostened 2 no fast rised 2.5 walk 2 2 3 h before regulary no occasionally occasionally sometimes sometimes grandma died for gdv
2 Yes german shepherd F 8 no 36 balanced dry miostened 2 yes slow soil 2.5 walk       occasionally no occasionally occasionally sometimes sometimes  
3 Yes spinone M 10 no 40 timid dry miostened 2 no fast rised 4.5 walk 2     never no occasionally never sometimes sometimes  
4 Yes german shepherd M 11 no 40 timid dry miostened 1 no normal soil 2 walk 2 1 1 h before, 12 h later never no occasionally occasionally yes yes  
5 Yes dalmatian M 5 no 30 aggressive dry 2 no fast soil 2.5 walk more than 4     never no never never sometimes yes  
6 Yes cross breed M 6 yes 70 balanced dry 2 no fast soil 2.5 walk 2     never no never never no no  
7 Yes german shepherd M 11 yes 40 timid homemade 1 no normal soil 2.5 walk more than 4     never no occasionally occasionally sometimes sometimes  
8 Yes german shepherd M 6 no 50 timid dry miostened 1 no voracious soil 2.5 walk more than 4     never no never occasionally sometimes sometimes  
9 Yes german shepherd M 9 no 40 exuberant dry miostened 2 no fast soil 2.5 walk 1 1 4 h before, 4 h later never no occasionally never sometimes sometimes  
10 Yes great dane F 3 yes 60 timid homemade 2 no voracoius soil 2.5 walk 3   match never no occasionally occasionally yes yes  
11 Yes boxer M 9 yes 40 balanced dry miostened 1 no voracious soil 4.5 walk 3 1   occasionally no occasionally never yes no  
12 Yes german shepherd F 8 no 30 timid homemade 1 no slow soil 2.5 walk   2 3 h before never no occasionally occasionally sometimes no  
13 Yes german shepherd F 11 yes 25 balanced dry miostened 1 no normal soil 2.5 living outside       never no occasionally occasionally sometimes no  
14 Yes drathar F 9 yes 23 timid dry 1 yes voracious soil 2.5 run       occasionally no occasionally never yes yes  
15 Yes dogue de bordaux F 7 no 55 balanced dry 2 no fast soil 2.5 walk more than 4 1 half an h before, 4 h later occasionally no never occasionally yes yes  
16 Yes setter gordon M 2 no 36 balanced dry 2 no slow soil 2 walk 1 5 1 h before, 3 h later regulary yes never never no no  
17 Yes great dane M 6 no 74 exuberant dry 2 no voracious soil 2 walk   5 2 h later never no occasionally never yes yes  
18 Yes briard F 4 no 35 exuberant dry 2 no normal soil 3.5 walk more than 4 5   never no never never sometimes sometimes  
19 Yes boxer M 12 yes 30 exuberant dry 1 no fast rised 2.5 walk 4 2 3 h later never yes occasionally never sometimes sometimes  
20 Yes german shepherd F 11 yes 33 balanced dry 1 no normal soil 2.5 living outside       never no never never yes yes  
21 Yes boxer M 5 no 34 exuberant homemade 1 no voracious soil 2 run 4 2 2 h before, 2 h later never no weekly never sometimes no  
22 Yes german shepherd M 2 yes 38 exuberant dry 2 no fast soil 2.5 walk 3 1 half an h later regulary no never never sometimes no  
23 Yes german shepherd M 8 no 40 exuberant dry 3 no fast soil 2.5 run 3     never no occasionally occasionally yes yes  
24 Yes curzar M 8 no 25 exuberant dry miostened 1 no voracious soil 2.5 run   4 1 h later occasionally no occasionally occasionally yes yes  
25 Yes chow chow M 8 no 28 timid homemade 1 no slow soil 2 nothing       never no never never yes no  
26 Yes brie shepherd M 8 yes 40 timid dry miostened 2 no fast soil 3.5 walk 1 2 5 h before, 6 h later never no never never yes no  
27 Yes german shepherd M 13 yes 40 timid homemade 2 no normal soil 2.5 walk 2 3   never no weekly occasionally yes yes  
28 Yes german shepherd F 7 yes 40 balanced homemade 1 no normal soil 2.5 run more than 4   1 h before, 1 h later never no occasionally occasionally sometimes no  
29 Yes german shepherd M 11 no 40 balanced dry 2 no voracious soil 2.5 living outside       never no occasionally occasionally yes no  
30 Yes samoiedo F 15 yes 30 balanced homemade 2 no fast soil 2.5 walk   1 few minutes occasionally no occasionally occasionally no no  
31 Yes german shepherd F 6 no 33 aggressive dry 1 no voracious soil 2 living outside       never no never never sometimes sometimes  
32 Yes Shitzu F 16 yes 6 balanced homemade 1 yes voracious soil 3.5 walk 2 0.5 6 h before, 4 h later never no weekly occasionally no no  
33 Yes german shepherd F 11 no 38 balanced dry 1 no normal soil 2.5 run 4 2 few minutes occasionally yes never occasionally no yes  
34 Yes great dane M 3 no 60 timid dry miostened 2 no voracious soil 2.5 living outside       never no weekly occasionally yes yes  
35 Yes irish setter M 8 no 30 balanced dry 1 no voracious soil 2 walk 3 5 8 h later regulary no weekly occasionally yes yes  
36 Yes griffin M 14 yes 3 exuberant dry miostened 2 yes voracious soil 2 walk 1   1 never no occasionally occasionally sometimes no  
37 Yes german shepherd M 8 yes 40 aggressive casalingo 1 no voracious soil 2.5 living outside       never no weekly never no no  
38 Yes great dane M 7 yes 65 balanced dry 2 no fast soil 2.5 nothing       occasionally yes occasionally occasionally sometimes no  
39 Yes dobermann M 6 yes 45 balanced dry miostened 1 no voracious soil 3.5 living outside       never no occasionally occasionally yes yes  
40 Yes sharpei F 11 yes 18 balanced homemade 1 yes slow soil 2.5 walk 3 2   occasionally no never never no no  
41 Yes maremma sheepdog F 6 yes 37 exuberant dry miostened 1 no slow soil 2.5 walk more than 4 2 2 h later never no occasionally never yes no  
42 Yes collie M 10 no 25 balanced homemade 1 yes normal soil 2.5 living outside       never no occasionally occasionally no yes  
43 Yes cross breed M 2 no 40 balanced dry 2 no normal soil 2.5 run   1   occasionally no occasionally occasionally yes yes  
44 Yes german shepherd M 5 yes 40 balanced dry miostened 1 no fast soil 2.5 walk 1 0.5   never no occasionally occasionally sometimes no  
45 Yes german shepherd M 7 no 37 timid homemade 1 no fast soil 2.5 walk 1 2 1 h before, 1 h later occasionally no occasionally occasionally sometimes no  
46 Yes german shepherd M 7 no 40 balanced homemade 1 no voracious soil 2 walk 1     never yes occasionally occasionally yes no  
47 Yes great dane F 5 no 50 timid dry 2 no fast soil 2 living outside       never no occasionally never yes yes  
48 Yes german shepherd F 8 yes 29 exuberant dry 1 no voracious soil 2.5 living outside       never no occasionally occasionally yes yes  
49 Yes bernese mountain dog F 3 yes 48 balanced dry 2 no voracious soil 2.5 run 1 1 1-2 h before never no occasionally occasionally sometimes sometimes  
50 Yes german shepherd F 5 no 32 timid homemade 1 yes slow soil 2.5 run       never no occasionally never sometimes sometimes  
51 Yes german shepherd M 7 no 45 exuberant homemade 2 yes voracious soil 2.5 run       never no never never sometimes sometimes  
52 Yes napolitan mastiff M 8 no 62 aggressive homemade 1 yes slow soil 2.5 living outside       never no occasionally never yes no  
53 Yes german shepherd M 7 yes 38 balanced dry miostened 2 no voracious soil 2.5 walk 2   3 h later never no occasionally never sometimes no  
54 Yes german shepherd M 9 yes 40 balanced dry 1 no normal soil 2 walk 1 1   never yes never never sometimes no  
55 Yes dobermann M 6 yes 32 balanced dry 2 no slow soil 2.5 walk 3 1   never no occasionally never sometimes no  
56 Yes cross breed M 7 no 45 balanced dry 1 no fast soil 2.5 living outside       never no occasionally never sometimes no  
57 Yes german shepherd M 10 no 33 exuberant dry miostened 1 no voracious soil 2.5 living outside       never no weekly never sometimes no  
58 Yes boxer M 12 yes 35 exuberant homemade 1 no fast rised 2.5 walk   0.5 6 h before, 6 h later regulary no occasionally never sometimes sometimes  
59 Yes bobtail M 11 no 40 timid homemade 2 no voracious soil 2 run 3 4 4-5 h before never no occasionally never sometimes no  
60 Yes boxer M 7 yes 20 exuberant homemade 1 no voracious soil 2.5 run more than 4     never no occasionally never yes no  
61 Yes english setter M 13 yes 25 exuberant dry miostened 1 yes normal soil 1.5 run more than 4     occasionally no occasionally occasionally yes yes  
62 Yes german shepherd F 10 yes 27 exuberant dry miostened 1 yes slow soil 2.5 living outside       never no never never yes no  
63 Yes akita inu M 9 yes 30 timid wet 1 no slow soil 2.5 living outside       occasionally no occasionally occasionally yes no  
64 Yes rhodesian ridgback M 9 no 40 balanced homemade 1 yes slow soil 2.5 nothing       never no occasionally occasionally yes no  
65 Yes terranova F 11 no 52 balanced dry 2 yes slow soil 2.5 walk 1 3 3 h before never no never never yes yes  
66 Yes samoiedo M 9 yes 35 balanced dry miostened 1 no voracious soil 2 walk 3 2 1 h and a half later occasionally no occasionally occasionally sometimes no  
67 Yes chow chow F 2 no 25 aggressive homemade 1 yes normal soil 2.5 walk 2 1   never no never never no no  
68 Yes boxer M 1 no 35 aggressive dry miostened 1 yes fast soil 4.5 nothing       never no never never no no  
69 Yes napolitan mastiff M 10 no 50 balanced dry miostened 1 yes normal soil 2.5 run 2 1   occasionally no never occasionally sometimes sometimes  
70 Yes italian hound M 4 yes 18 balanced dry miostened 1 yes voracious soil 2 nothing       never no never occasionally sometimes sometimes  
71 Yes german shepherd M 9 no 30 balanced homemade 1 yes fast soil 3.5 nothing       never no never never no no  
72 Yes schnauzer M 6 no 40 timid homemade 1 yes normal soil 2.5 walk   2 2 h bfore regulary no occasionally never sometimes sometimes  
73 Yes german shepherd M 2 no 40 balanced homemade 2 no normal rised 2.5 walk 2 3   regulary no never never yes no  
74 Yes dobermann M 8 yes 38 balanced homemade 2 no voracious rised 2.5 living outside       never rarely never never no no  
75 Yes cross breed F 9 no 20 balanced dry 1 no fast soil 1.5 living outside       occasionally rarely never occasionally sometimes no  
76 Yes great dane M 3 no 70 timid dry 2 yes slow soil 2.5 walk   2   never yes occasionally never yes no  
77 Yes saint bernard M 6.5 no 70 balanced dry 1 yes voracoius rised 3.5 walk 2 1   occasionally no never never yes yes  
78 Yes great dane M 7 no 70 balanced dry 1 yes voracious soil 3.5 walk   2 3 h later never no occasionally occasionally yes no  
79 Yes german shepherd M 5 no 42 exuberant dry 2 yes slow rised 2.5 run 1 4 2 h before, 2 h later never no never never no no  
80 Yes german shepherd M 7 no 37 balanced dry 1 no normal soil 2 run 4 4   regulary no occasionally occasionally sometimes sometimes  
81 Yes greyhound F 10 no 30 timid homemade 2 no voracious soil 2.5 run more than 4 4   never no never never no no  
82 Yes dobermann F 8 no 30 balanced homemade 1 no voracious soil 2.5 walk 4 2 mezz'ora prima never no weekly occasionally no no  
83 Yes brie shepherd M 4 yes 40 balanced dry 2 yes slow soil 2.5 living outside       never no never never yes no  
84 Yes alaskan malamute M 11 no 40 balanced dry miostened 1 no slow soil 2 walk 3 2   regulary no occasionally occasionally sometimes yes  
85 Yes terranova M 9 no 60 balanced dry 1 yes normal soil 2.5 walk more than 4     never no occasionally occasionally sometimes no  
86 Yes rottweiller F 5 yes 40 balanced homemade 2 no fast soil 2.5 living outside       never no occasionally never sometimes yes  
87 Yes cane corso M 6 no 60 balanced dry 1 yes normal soil 2 run more than 4 4 half a h before, 4 h later regulary no occasionally occasionally yes yes  
88 Yes cross breed M 6 no 30 balanced dry 2 no voracious soil 2.5 run more than 4 2   never no occasionally occasionally sometimes sometimes  
89 Yes boxer F 7 no 20 timid dry miostened 1 no voracious soil 2.5 walk       never no occasionally never no no  
90 Yes cross breed M 12 yes 44 balanced homemade 1 yes normal soil 2.5 run       regulary no never never sometimes no  
91 Yes dobermann F 7 no 30 balanced dry 2 no normal rised 2 walk 1 1 3 h before occasionally no occasionally weekly yes no  
92 Yes german shepherd F 13 yes 26 timid homemade 1 no voracious soil 2.5 walk more than 4 3   never no occasionally never no no gdv last year, no surgery
93 Yes great dane M 9 no 75 balanced dry miostened 3 no normal soil 2.5 living outside       occasionally no never never yes yes  
94 Yes german shepherd F 3 yes 44 aggressive homemade 2 no voracious soil 2.5 run more than 4     never no never never sometimes sometimes  
95 Yes cross breed F 7 yes 26 exuberant homemade 1 yes voracious soil 2 living outside       regulary no never never sometimes sometimes  
96 Yes dobermann M 10 no 35 balanced homemade 2 no normal rised 2.5 living outside       never no occasionally occasionally sometimes sometimes  
97 Yes german shepherd M 5 no 40 exuberant homemade 2 no voracious soil 2.5 walk 2 2 1 h later occasionally no never never yes yes gdv 2 years later, no vet treatment
98 Yes chow chow M 11 no 30 balanced dry miostened 2 no voracious soil 2.5 walk 1 0.5   never no occasionally occasionally sometimes no  
99 Yes chow chow M 13 no 30 aggressive homemade 1 no voracious soil 2.5 run more than 4 4 12 h later occasionally yes occasionally occasionally sometimes sometimes  
100 Yes german shepherd F 11 no 33 balanced dry miostened 1 no voracious soil 2.5 run 3 3 1 h before, 4 h later never no never never no no  
101 Yes great dane F 4 no 50 timid dry miostened 3 no fast soil 1.5 living outside       never no occasionally occasionally yes yes  
102 Yes cane corso M 7 no 40 balanced dry 2 yes normal soil 3.5 walk more than 4 1 1 h before, 1 h later never no occasionally never yes yes  
103 Yes dachshund F 12 no 10 aggressive homemade 1 no voracious soil 2 walk 4   half a h before, half a h later never no occasionally never no no  
104 Yes german shepherd M 11 no 35 balanced homemade 1 yes slow soil 2.5 walk more than 4 2   never no occasionally never sometimes sometimes  
105 Yes german shepherd M 12 no 35 aggressive dry miostened 1 yes voracious soil 2.5 walk 1     never no occasionally occasionally sometimes no  
106 Yes bavarian hound F 8 yes 20 aggressive dry 2 no voracious soil 2.5 living outside       never no never occasionally sometimes no  
107 Yes maremma sheepdog M 8 no 55 balanced dry 2 yes slow soil 2.5 walk 3 3 1 h before never no occasionally occasionally yes no  
108 Yes leonberger M 9 no 70 balanced homemade 2 no fast soil 2.5 run 1 1 2 h later occasionally yes never occasionally yes yes  
109 Yes german shepherd M 6 no 40 timid dry 2 no normal soil 3.5 walk 1 1 2 h before, 2 h later never no occasionally never no no  
110 Yes italian hound F 13 no 30 timid homemade 1 yes voracious soil 2 walk 1 1 3 h later never no never never sometimes sometimes  
111 Yes dobermann M 8 no 30 exuberant dry miostened 3 no fast soil 2.5 run 2 1 2 h before never no occasionally occasionally sometimes no  
112 Yes great dane M 2 no 70 timid dry miostened 2 no normal soil 2 nothing       never no never never no no  
113 Yes dalmatian M 5 no 20 balanced dry miostened 2 no voracious soil 1.5 living outside       never no occasionally never yes yes  
114 Yes german shepherd F 7 yes 35 timid dry 1 no voracious soil 2.5 living outside       never no never never no no  
115 Yes great dane F 7 no 75 balanced dry 3 no slow rised 2.5 living outside       never no never never yes no  
116 No bernese mountain dog M 2 no 45 balanced dry 3 no normal rised 2.5 nothing       occasionally no never occasionally sometimes no  
117 No bernese mountain dog M 4 yes 50 exuberant dry 2 no normal soil 2.5 living outside       occasionally no occasionally occasionally sometimes no  
118 No bernese mountain dog M 3 yes 44 balanced dry 2 no normal soil 3.5 walk 1 2 1 h before, 1 h later occasionally no never never sometimes sometimes  
119 No bernese mountain dog M 7 yes 45 balanced dry 2 no normal soil 2.5 walk 2 1.5 1 h before occasionally no never never no no grandma died for gdv
120 No bernese mountain dog M 1.5 no 40 balanced dry miostened 3 no normal soil 2.5 run more than 4     never no never never sometimes sometimes  
121 No bernese mountain dog M 4 no 52 balanced dry 2 no slow rised 2.5 walk more than 4 4 1 h before, 1 h later occasionally no occasionally occasionally yes yes  
122 No bernese mountain dog F 7 yes 45 balanced dry miostened 2 no normal soil 3.5 walk 1 1 3 h before never no never never no no  
123 No bernese mountain dog F 7 yes 38 balanced dry miostened 2 no normal soil 2.5 walk 1 1   occasionally no occasionally never no no  
124 No bernese mountain dog F 1 no 35 balanced dry miostened 3 no normal soil 2.5 run more than 4     never no never never sometimes sometimes  
125 No bernese mountain dog F 1.5 no 36 balanced dry 2 no normal soil 2.5 walk 2 2 2 h before, 2 h later occasionally no never never sometimes sometimes  
126 No bernese mountain dog F 3 no 36 balanced dry miostened 2 no normal soil 2.5 walk 2 1 3 h before, 3 h later occasionally no never never sometimes sometimes  
127 No bernese mountain dog F 2 no 41 balanced dry miostened 2 no fast rised 2.5 walk 2 2 2 h before, 2 h later occasionally no occasionally occasionally sometimes sometimes  
128 No bernese mountain dog F 3 no 50 exuberant homemade 1 yes normal soil 2.5 walk   1 6 h before never yes occasionally occasionally yes yes  
129 No bernese mountain dog F 1.5 yes 35 balanced dry 3 no normal soil 2.5 walk 2 1 1 h before never no occasionally occasionally sometimes sometimes  
130 No argentine dogo F 8 yes 50 balanced homemade 2 no normal soil 2.5 walk 3 3 3 h before occasionally yes never never no no  
131 No great dane M 8 no 60 exuberant dry 2 yes normal rised 2.5 run 1   2 h later occasionally no never never sometimes sometimes  
132 No irish setter F 8 no 20 balanced dry 1 no normal soil 2.5 living outside       occasionally yes never never sometimes sometimes  
133 No cross breed F 1 no 25 exuberant dry 2 no normal soil 2.5 run 1 2 3 h before never no never occasionally sometimes sometimes  
134 No boxer M 4 no 36 balanced dry 2 no normal soil 2.5 walk 3 1 half a h later regulary yes occasionally occasionally sometimes sometimes  
135 No akita inu F 9 yes 40 balanced dry 2 no voracious soil 2.5 walk 1 0.5 1 h later occasionally no occasionally occasionally yes yes  
136 No great dane F 4 no 50 timid dry 1 no normal soil 2.5 living outside       never no never never no no  
137 No german shepherd M 2 no 34 balanced dry miostened 2 no fast soil 2.5 nothing       never no never never yes yes  
138 No cross breed F 10 yes 45 timid dry miostened 1 no normal soil 2.5 walk more than 4 2 suddenly after the meal never no occasionally never sometimes sometimes  
139 No german shepherd F 8 yes 34 timid dry miostened 1 no fast soil 3.5 living outside       occasionally no never never sometimes no  
140 No rottweiler M 2 no 46 balanced homemade 1 yes fast rised 2.5 living outside     2 h later never no occasionally occasionally sometimes no  
141 No french bulldog M 7 yes 12 balanced homemade 1 no normal soil 2.5 living outside 1 0.5   regulary no occasionally occasionally yes no  
142 No border collie M 9 no 27 exuberant dry miostened 2 yes slow soil 2.5 run more than 4     never no occasionally occasionally sometimes no  
143 No boxer M 1,5 no 25 exuberant dry 2 no slow soil 2 walk 2 3 2 h later never no never occasionally sometimes no  
144 No alaskan malamut M 11 yes 55 balanced dry 1 no normal soil 3.5 walk 1 0.5 5 h later occasionally no occasionally occasionally sometimes no  
145 No greyhound F 8 yes 20 balanced dry 1 no slow soil 2.5 living outside       never no never never sometimes no  
146 No cross breed M 8 yes 30 balanced dry 1 no normal rised 2.5 living outside       never no never never no no  
147 No rottweiler M 11 no 60 balanced dry 1 no normal soil 3.5 living outside       never no never never sometimes no  
148 No golden retriver F 6 no 35 exuberant dry 2 no normal soil 3.5 walk 1 1 2 h later never no never occasionally sometimes no  
149 No alaskan malamut M 3 no 39 aggressive homemade 2 no fast soil 2.5 living outside       never no occasionally never yes no  
150 No french bulldog M 4 no 15 balanced dry 2 no fast soil 2.5 walk 1 1 5 h later never no occasionally never sometimes no  
151 No cross breed M 10 yes 12 balanced dry 2 yes fast soil 2.5 walk 1 0.5 3 h later never no occasionally never sometimes no  
152 No dwarf dachshund M 6 no 6,5 balanced dry 1 yes normal soil 2.5 walk 1 1 1 h later occasionally no occasionally never no no  
153 No border collie F 4 yes 25 exuberant dry 2 no normal soil 2.5 living outside 1     never no occasionally never yes no  
154 No beagle M 11 no 23 balanced dry 2 no fast soil 2.5 walk 4 0.25 half a h later never no never never sometimes no  
155 No terranova F 14 yes 40 balanced homemade 1 no voracious soil 2.5 living outside       never no never never no no  
156 No dobermann M 13 no 55 balanced homemade 1 no voracious soil 2.5 living outside       occasionally no never never no no  
157 No maremma sheepdog M 14 no 65 balanced homemade 1 no slow soil 2.5 living outside       occasionally no never never no no  
158 No rottweiler F 13 yes 40 balanced homemade 1 no fast soil 2.5 living outside       occasionally no never never no no  
159 No great dane F 7 yes 65 balanced dry 3 no normal soil 2.5 living outside 3     regulary no never occasionally no no  
160 No great dane M 5 no 70 balanced dry 2 no normal soil 2.5 living outside 3     regulary no never occasionally no no  
161 No cane corso F 5 yes 65 aggressive homemade 1 no fast soil 2.5 living outside       never no never never no no  
162 No maremma sheepdog F 15 yes 50 balanced homemade 1 no normal soil 2.5 living outside       never no never never no no  
163 No beagle M 8 no 20 balanced dry 2 no fast soil 2.5 walk 1 2 2 h later never no occasionally occasionally yes no  
164 No golden retriver F 8 yes 27 balanced dry 2 no normal soil 2.5 walk 1 1 6 h later never no never never no no  
165 No cane corso M 13 yes 37 balanced dry 1 no normal soil 2.5 living outside       never no never never yes no  
166 No cross breed M 10 no 13 balanced dry 1 yes normal soil 2.5 walk 2 0.5 suddenly after the meal regulary no occasionally occasionally sometimes sometimes  
167 No border collie F 12 yes 25 balanced dry 1 no normal soil 2.5 walk 2 2 suddenly after the meal occasionally no never occasionally sometimes no  
168 No cross breed F 13 yes 21 esuberanteex wet 1 no voracious soil 2.5 living outside 1 0.5 1 h before regulary no never never sometimes no  
169 No dobermann M 2 no 57 timid dry 2 no normal soil 2.5 living outside 2 0.5 2 h later never no never never sometimes no  
170 No bernese mountain dog F 2 no 40 balanced dry miostened 2 no normal soil 2.5 nothing       never no never never no no  
171 No bernese mountain dog F 1 no 40 balanced dry miostened 2 no normal soil 2.5 walk 1 3 1 h before, 1 h later occasionally no never never sometimes no  
172 No bernese mountain dog M 4 yes 50 balanced dry 2 yes slow soil 2 walk 2 1 1 h before occasionally no occasionally occasionally sometimes no  
173 No bernese mountain dog M 4 yes 40 balanced dry 3 no fast soil 2.5 walk 1 3 2 h before, 2 h later occasionally no never never sometimes no  
174 No bernese mountain dog M 2 no 50 balanced dry miostened 3 no normal soil 2.5 walk 1 1 2 h later occasionally no never occasionally no no  
175 No bernese mountain dog M 2 no 55 balanced dry 3 yes normal soil 2.5 walk 1 1 2 h before, 2 h later occasionally no never never sometimes no  
176 No bernese mountain dog M 3 yes 40 balanced dry miostened 2 yes slow soil 1.5 walk 1 1   occasionally no occasionally occasionally sometimes no  
177 No irish setter F 8 yes 25 balanced dry 1 yes normal soil 2.5 living outside       never no never occasionally no no  
178 No english setter F 8 yes 25 balanced dry 1 yes normal soil 2.5 living outside       never no never never no no  
179 No cross breed F 6 no 15 balanced dry 2 no normal soil 2.5 living outside 1 1 2 h later occasionally no never never no no  
180 No german shepherd F 7 yes 43 balanced dry 1 no fast soil 2.5 living outside       never no never never no no  
181 No german shepherd M 5 no 52 esuberanteex dry 1 no fast soil 2.5 living outside       never no never never sometimes no  
182 No golden retriver M 1 no 32 balanced dry 3 no normal soil 2.5 run 4 4 2 h later regulary no never never sometimes no  
183 No great dane F 7 yes 60 balanced dry 2 no fast rised 2.5 living outside 1 1 3 h later never no occasionally never sometimes no  
184 No czechoslovakian wolf M 5 no 36 aggressive dry miostened 1 no fast soil 2.5 living outside 2 2 2 h before occasionally no occasionally occasionally no no  
185 No labrador retriver M 7 no 35 balanced dry 2 no fast rised 3.5 walk 2 1 1 h before never no occasionally occasionally sometimes no  
186 No german shepherd F 8 yes 34 timid dry miostened 1 no fast soil 3.5 living outside       occasionally no never never sometimes no  
187 No leonbergher M 8 no 60 balanced dry miostened 1 yes slow soil 2.5 living outside       occasionally no never occasionally sometimes no  
188 No cross breed M 0.5 no 17 balanced miscellaneous 2 no slow soil 2.5 walk 2 1 4 h later never no never never no no  
189 No german shepherd M 9 no 33 balanced dry 1 no normal soil 2.5 living outside 2   4 h later occasionally no never never sometimes no  
190 No cross breed M 2 no 11 balanced dry 2 yes normal soil 2.5 living outside 3 2 3 h later never no never never sometimes no  
191 No hound M 3 no 23 timid dry 2 yes slow soil 2.5 living outside 2 3 1 h before, 1 h later never no never occasionally no no  
192 No czechoslovakian wolf F 1 no 23 exuberant dry 3 no fast soil 2.5 walk 3 3 1 h later occasionally yes weekly occasionally no yes  
193 No english setter M 1,5 no 22 exuberant dry 2 no voracious soil 2.5 living outside       never no never never no yes  
194 No pittbull M 4 no 30 timid dry 2 no voracious soil 2.5 living outside       never no never occasionally sometimes no  
195 No german shepherd M 0.58 no 28 balanced dry 2 no normal soil 2.5 living outside       never no occasionally never yes no  
196 No german shepherd F 0.5 yes 18 exuberant dry 2 no fast soil 2.5 living outside       never no never occasionally no no  
197 No sharpei M 15 no 18 aggressive dry 1 yes voracious soil 2.5 walk 1 0.5 8 h before never no never never no no  
198 No labrador retriver F 7 yes 28 balanced dry 3 no normal soil 2.5 nothing       never no never never yes no  
199 No husky M 15 no 23 balanced wet 1 yes slow soil 2.5 walk 3 2 2 h before occasionally no never never no no  
200 No weimaraner M 1 no 26 exuberant wet 2 no voracious soil 2.5 walk 4 0.25 2 h before never no occasionally occasionally yes yes  
201 No beagle F 10 yes 14 timid dry 2 no fast soil 2.5 living outside 1 1 3 h before occasionally no occasionally never sometimes sometimes  
202 No german shepherd F 7 yes 32 balanced homemade 1 no fast soil 2.5 walk 2 2 2 h later never no never never no sometimes  
203 No hound M 6 no 17 timid dry 1 no normal soil 2.5 living outside 2 1 1 h before, 2 h later never no occasionally occasionally sometimes no  
204 No dalmatian F 9 no 20 exuberant dry 3 no slow soil 2.5 living outside 2 1 2 h before, 2 h later never no never never no no  
205 No dalmatian M 9 no 29 exuberant dry 3 no slow soil 2.5 living outside 2 1 2 h before, 2 h later never no never never no no  
206 No husky F 1 no 20 balanced dry 1 yes slow soil 2.5 living outside 1 0.5 2 h before never no never never sometimes no  
207 No husky M 1 no 27 balanced dry 1 yes voracious rised 2.5 living outside 1 0.5 2 h before never no never never no no  
208 No husky F 2 no 21 balanced dry 1 yes normal rised 2.5 living outside 1 0.5 2 h before never yes never never no no  
209 No husky M 2 no 27 balanced dry 1 yes normal rised 2.5 living outside 1 0.5 2 h before never yes never never no no  
210 No german shepherd M 6 no 40 balanced dry 1 yes normal rised 2.5 living outside 1 0.5 2 h before never yes never never no no  
211 No border collie M 4 no 25 balanced dry 1 yes normal rised 2.5 living outside 1 0.5 2 h before occasionally no never never no no  
212 No spinone cross M 2 no 35 balanced dry 1 yes voracious rised 2.5 living outside 1 0.5 2 h before never no never never no no  
213 No german shepherd F 10 no 30 balanced dry 1 yes normal rised 2.5 living outside 1 0.5 2 h before never no never never yes no  
214 No pittbull F 1 no 25 balanced dry 1 yes normal rised 2.5 living outside 1 0.5 2 h before never no never never no no  
215 No boxer F 9 no 30 balanced dry 2 no fast soil 2.5 living outside 4 0.5 1 h later occasionally no never occasionally sometimes sometimes  
216 No labrador cross M 8 yes 30 exuberant homemade 2 no normal soil 2.5 living outside       never no never never sometimes no  
217 No afghan greyhound M 12 yes 30 balanced dry 2 no normal soil 2.5 walk 2 0.5   never no never never no no  
218 No afghan greyhound F 2 yes 15 timid homemade 2 no normal rised 1.5 living outside       never no never never no no  
219 No afghan greyhound M 10 yes 30 exuberant homemade 2 no normal rised 2.5 living outside       never no never never no no  
220 No afghan greyhound M 9 yes 30 balanced wet 2 no fast rised 2.5 living outside 2 0.5   never no never never no no  
221 No malinois cross M 1 yes 24 balanced dry 2 no normal rised 2.5 living outside       never no never never sometimes no  
222 No labrador cross M 5 yes 30 balanced dry 2 no normal rised 2.5 living outside       never no never never sometimes no  
223 No australian shepherd M 2 no 35 balanced homemade 2 yes fast soil 2.5 living outside     2 h later never no never never no no  
224 No labrador retriver M 1 no 30 balanced dry 3 no slow rised 2.5 walk 4 2 1 h later never no never never sometimes no  
225 No german shepherd F 3 yes 42 timid dry 1 no fast soil 2.5 nothing       never no never never no no  
226 No weimaraner F 4 no 30 timid dry 2 no voracious soil 2.5 living outside       never no never never sometimes no  
227 No german shepherd M 4 no 40 balanced dry 2 no normal soil 2.5 living outside       never no occasionally never sometimes no  
228 No german shepherd F 10 no 35 timid homemade 2 no fast soil 2.5 walk 1 2 3 h before never no occasionally occasionally yes no  
229 No boxer M 10 yes 35 balanced dry 2 no normal soil 2.5 walk 1 1 3 h later never no occasionally occasionally sometimes no  
230 No boxer F 5 yes 30 balanced homemade 2 no normal rised 2.5 walk 1 2 2 h later never no never never no no  
Statistical Analysis

Statistical analysis, performed using statistical software R. Data was merged making non-dichotomous variables into dichotomous variables. For example, for the "food intake speed" parameter, the owner could choose between four answers: slow, normal, quick, voracious. The data was then grouped in slow/normal (Group 1) and fast/voracious (Group 2), using the Pivot tables. This procedure was carried out for all non-dichotomous variables (i.e. those variables for which the answer did not include a simple YES/NO but a scale of values). These variables were: the speed of food intake; temperament of the dog, type of feeding, position of the bowl, number of meals, type and frequency of physical activity, presence of episodes of vomiting and/or diarrhoea, tendency to eat foreign bodies, tendency to consume grass, stay in kennels, and whether it was used to long journeys.

Once all dichotomous variables were rendered, each parameter was entered in 2x2 contingency tables. For some variables, several 2x2 tables were created, for example 4 tables were created for physical activity including the possibility to carry out physical activity, the possibility to carry out physical activity before the meal, the possibility to carry out physical activity after the meal, possibility to perform physical activity before and after the meal.

From the 2x2 contingency tables the following values were calculated: OR, ES, OR MIN and OR MAX. OR is a statistical value that represents the relationship between sick and exposed subjects and the healthy and exposed subjects. It is calculated as (a/c)/(b/d), ie (cases/non-cases) exposed/(cases/non-cases) not exposed. (Table 2).

Dogs, feeding and physical activity caracteristics. The relationship between different carecteristics and statistic values: OR, OR MIN, OR MAX, ES and P Value
Variabile GDV 115/230 CONTROL 115/230 TOT CASES 230 TOT CONTROLS 115/230  OR OR MIN OR MAX ES Pvalue
SIZE – large+giant breed, n 100 85 115 115 2,35 1,19 4,66 0,35 0,0200
BREED - pure breed, n 109 94 115 115 4,06 1,57 10,48 0,48 0,0041
SEX - male 76 65 115 115 1,50 0,88 2,56 0,27 0,1758
AGE - > 3 years of age 103 75 115 115 4,58 2,25 9,32 0,36 0,00002
SEX - intact 73 68 115 115 1,20 0,71 2,04 0,27 0,5881
WEIGHT - >30 kg 79 61 115 115 1,94 1,13 3,33 0,27 0,0216
TEMPER – shy oraggressive nature 27 27 82 106 1,44 0,76 2,71 0,32 0,3382
FEEDING only dry or wet food 93 84 115 115 1,56 0,84 2,90 0,31 0,2103
FEEDING with dry food 41 22 115 115 2,34 1,28 4,27 0,30 0,0078
FEEDING moistened dry food 31 19 115 115 1,86 0,98 3,54 0,32 0,0374
FEEDING once daily 62 44 114 114 1,90 1,12 3,21 0,26 0,0240
FEEDING available all day long 32 27 112 113 1,27 0,70 2,31 0,30 0,5183
FEEDING Rapid+Voraciuous eating 69 38 115 115 3,04 1,77 5,21 0,27 0,0731
BOWL POSITION – on the ground 105 92 115 115 2,63 1,19 5,80 0,40 0,0240
BODY CONDITION – overweight or obese 12 8 115 115 1,56 0,61 3,97 0,47 0,4827
EXERCISE- 81 67 115 115 1,71 0,99 1,96 0,27 0,0735
EXERCISE >once daily 49 38 66 75 2,81 1,37 5,73 0,36 0,0069
EXERCISE before the meal 26 34 43 67 1,48 0,68 3,23 0,27 0,4222
EXERCISE after the meal 76 65 115 115 1,50 0,88 2,56 0,27 0,1758
EXERCISE before and after the meal 16 12 43 67 2,72 1,13 6,54 0,44 0,0411
NOT USED TO LONG TRIPS 81 72 115 115 1,42 0,82 2,47 0,28 0,2637
USED TO KENNELS/DOGHOUSES 11 8 115 115 1,41 0,55 3,66 0,48 0,6319
VOMITING 75 33 115 115 4,66 2,67 8,13 0,28 0,0001
DIARRHEA 51 36 115 115 1,75 1,02 3,00 0,27 0,0570
EATING FOREIGN BODIES 54 23 115 115 3,54 1,97 6,36 0,29 0,0277
EATING GRASS 93 68 115 115 2,92 1,61 5,30 0,30 0,0006

The values OR MIN and OR MAX indicate the confidence interval, that is, define how much the OR value represents the estimate of a real value. The confidence interval makes it possible to verify the statistical significance of the results: if it contains the value 1, the null hypothesis is satisfied (ie that there is no difference between exposed or non-exposed subjects to risk factors). If the confidence interval does not contain the value 1, the null hypothesis is rejected, i.e. the alternative hypothesis is accepted, which states that there is a difference between exposed and non-exposed subjects to the risk factor, so that the OR value is significant (Table 3).

The relationship between OR, for the different evaluated variables, in GDV cases and control cases

After calculating the OR value of each variable, χ2-tests were performed; p values of < 0.05 were considered statistically significant.

 Results

In total, 86.9% (100/115) of dogs presented with GDV were large/giant breeds while only 13.1% (15/115) were medium/small breeds. Among the control dogs, 54.84% (85/155) were large-giant breeds and 19.35% (30/155) medium/small breeds. In total, 94.7% of GDV dogs and 81.7% of control dogs were purebred dogs. Out of 115 cases, 76 GDV dogs (66%) were male and 39 (34%) female. The control group consisted of 65 (56.5 %) male and 50 (43.4 %) female dogs. Most dogs were older than three years of age, 93% (108/115) of GDV dogs and 71.3% (82/115) of control dogs. Most dogs had a low to normal BCS, 90% of GDV dogs and 93% of control dogs respectively and 68.6% of GDV dogs (79 /115) and 65% (75/115) of control dogs were > 30 kg.

The majority of GDV dogs (76.6%) had a balanced temperament, whereas 23.4% were classified as being shy, aggressive or having an exuberant character.

When considering diet as a variable, 19% of GDV dogs (22/115) consumed a combination of commercial and homemade diet, while the remainder 81% (93/115) were either fed only a commercial diet or a homemade only diet. On the other hand, in the control dog group 26.9% (31/115) of dogs received a combination of commercial and homemade diet. (OR = 1,56, CL 95% = 0,84 – 2,90 and P = 0,2).A total of 230 animals consumed dry food, 64.3% (74/115) GDV dogs and 80.8% (93/115) of control dogs, respectively, and 73. 1 % cases (84/115) and 83.5% controls (96/115) ) were fed dry food. Form these data results a positive statistic association between the dry food diet and the developpement of GDV (OR=2,34 CL 95%=1,28-4,77 and P=0,007). Overall, 62/115 (53.91%) GDV dogs were only fed once a day versus 44/115 (38.26%) control dogs. For this epidemiological variable too results a positive statistic association (OR = 1,90 CL 95% = 1, 12 – 3,21 and P = 0,02).

Out of a total of 230 animals, 13,9 % (32 / 230) GDV dogs and 11.7% (27 / 230) controls dogs had access to food throughout the day ad libitum; 69, 5 % (80 / 115) DGV dogs and 74,7 % (86 / 115) had not access to food throughout the day and ad libitum. Statistic analysis of these data did not show a valid and true association between our results and the development of GDV (OR 0 = 1,27 CL 95% = 0, 70 - 2,31 P = 0,5).

The analysis of meal intake rates showed that 40% of GDV dogs (46 / 115 ) and 66% of control dogs (38 /115) consumed their meal slowly, while 60% of affected cases (69/115) and 34% of controls (38/115) eat the meal quickly or voraciously. This trend would be a positive risk factor for development of GDV. However even if OR = 3,04 and CL 95% = 1,77 – 5,21 the result is not supported by a P Value that defines the statistically valid association ( P = 0,07)

About the position of the bowel, the 91,4 % (105/115) of GDV dogs was fed with the bowl on the ground, whereas only the 8, 6 % (10/115). Between controls 80% (92/115) consume the meal with bowl on the ground and 20% (23/115) with raised bowl. Final data (OR= 2,63 95%CL = 1,19 – 5,80 and P = 0,02) define de statistically valid association.

Cases and controls were compared according to two groups of BSC: obese or overweight subjects (group 1) and thin or weight-form subjects (group 2). 10% of cases (12 / 115) were assigned in group 1, while the remaining 90% (103 / 115) was assigend to group 2. In the control sample the 6,9% (115/8) was overweight-obese and 93% (107/115) was thin or weight-form. The result is OR = 3.97, but CL 95% = 0.61-3.97 and P = 0.4 for which there is no statistically valid association.

Noumerous are the data obtained regarding the study as a possible risk factor for GDV. Out of 115 GDV dogs, 70.5% (81/115) performed physical activity during daytime (they are considered dogs that live in the garden and/or are taken on a walk by the owner), versus 50.5% (34/115) of control dogs considered sedentary animals, living in an apartment or at home without having access to the outside or animals that are not regularly walked by the owner. In this case, even if OR = 1.71, CL 95% = 0.99-1.96 and negative Chi square test (P = 0.07), the association is statistically significant.

Among the dogs performing physical activity, 74.2% (49/66 )GDV dogs and 50.6% (38/75) control dogs performed physical activity more than once daily. For this variable, OR is calculated equal to 2.81, CL 95% = 1.37-5.73 and P = 0.006 for which the statistical test is valid and there is an evident association between this variable and the GDV.

About physical activity compared to meal timing, we report that 60% of GDV dogs (69/115) did physical activity before the meal and the 40% (46/115) did not before and that 58% (67/115) of control group did activity before meals compared to the 28,6% (33/115) that did not. Our statistical analysis with OR = 1,48 CL 95% = 0,68 – 3,23 and P = 0,04% show that our results are not statistically valid. Regarding potential stress factors, 29.5% of GDV dogs (34/115) and 37.3% (43/115) of control dogs were used to join the owner on long journeys and trips by car. In total, 9.57% of GDV (11/115 ) dogs and 6.96% of control dogs (8/115) were used to staying in pensions or kennels. With values of OR=1,41, CL 95%=0,55-3,66 e P=0,6 not event this statistical analysis is significant for developping of GDV. In 65.2% of GDV dogs (72/115) there was a history of frequent vomiting, while only 28.6% of control dogs (33/115) had regular episodes of vomiting (OR= 2,63 95%CL = 1,19 – 5,80 and P = 0,02). Episodes of diarrhea were reported in 44.3% (51/115) of GDV dogs and 31.3% of control dogs (36/115) , respectively (OR=1,75, CL 95%=1,02-3 e P=0,057). Ingestion of foreign was present in 38.2% of GDV dogs (44/115) and in 20% of control dogs (23/115). Finally, 80.8% of GDV dogs (93/115) and 59.1% of control dogs (68/115) were reported to ingest grass or foreign bodies (OR=3,54, CL 95%=1,97-6,36 e P=0,02). Due to these 3 last results listed above as predisposing factors (vomiting, dhiarrea and foreign bodies) and consideting the results we can conclude that all three have a statistical positive significance.

In Table 1 and Table 2 statistical analyses of risk factors are summarized. Several predisposing risk factors were identified. There was a significant difference between large/giant dogs and medium/small dogs, with large and giant dogs having 2.35 odds to develop a GDV (OR = 2.35, 95% CL = 1.19-4.66 and P = 0.02).

Purebred dogs are also statistically significantly more likely to develop GDV, with an OR of 4.06. Dogs older than three years of age and dogs over 30 kg are also at increased risk, with OR of 4.58 and 1.94, respectively. Regarding food, a positive statistical association was found between dogs receiving dry food and the development of GDV (OR = 2.34). Dogs that only receive one meal a day, and dogs that consume the meal from a bowl on the floor are at increased risk (OR= 1.90 and 2.63, respectively). There was a trend of fast eating being a risk factors, however this revealed to not be statistically significant. Dogs performing daily activity, dogs that have physical activity several times daily, and dogs that perform physical activity around the meal are at increased risk of developing GDV (OR = 1.71, 2.81, and 2.72, respectively). A strong association was found between dogs having regular episodes of vomiting and GDV and also between dogs having regularly diarrhea and the development of GDV (OR = 4.66 and OR = 1.75, respectively). Ingestion of foreign bodies and ingestion of grass were likewise risk factors for the development of GDV (OR = 3.54 and OR = 2.92, respectively).

 Discussion

This case-control study revealed several predisposing risk factors for the development of GDV in this population of dogs which are similar to risk factors previously described. The results support the data from existing literature that there is a significant difference between large/giant breed dogs and medium-small dogs7,12,23 and that the subjects in the first group are more likely to develop GDV (OR = 2.35, 95% CI 1.19 - 4.66 and P = 0.02).

In this study there was little difference between the occurrence of GDV in large or giant breeds. This correlates with other studies which have previously found no significant difference between the incidence of GDV between large and giant breeds. In this study German Shepherd (51dogs/115), Great Dane (14 dogs/115) and Dobermann (8 dogs/115) were the most represented breeds. Other breeds exhibiting disease include: Akita Inu, Bobtail, Boxer, Bernese Mountain Dog, Cane Corso, Chow Chow, Dalmatian, Dogue de Bordeaux, Drahthaar, Greyhound, Leonberger, Neapolitan Mastiff, Shepherd of Brie, Shepherd of Maremma, Rhodesian Ridgeback, Rottweiler, Samoyed, Giant Schnauzer, Bavarian Hound, Italian Hound, Setter Gordon, Irish Setter and Newfoundland.

Purebred dogs are reported to present a significant risk factor for GDV10,12,23,25. Compatible with existing literature21,23, this research also demonstrates purebred dogs have an increased likelihood of developing GDV. A case-control study done by Glickman et al. in 199717 calculated that among a group of 1114 cases, 1089 dogs were purebred dogs (13% German shepherd, 12% Hay, 6% Standard Poodle, 4% Doberman, 63% other breeds) and that only 25 the dogs were mixed breed17.There is variation in individual studies between the breed most predisposed to GDV and this has been thought to depend on the breed most widespread within a particular region.

Weight is also reported to represent a significant risk factor10,17. Dogs weighing 30 kg or more have 1.94 times more likely to others of developing GDV and large mixed breed dogs are more at risk than small breeds24.

Schellenberg et al. found female dogs present a higher risk for GDV than male dogs26. Pipan et al. in a published case control study of 2012 found that the OR of intact females showed them to be more predisposed to the development of GDV23. This finding was not supported in this study; male dogs appeared more predisposed to GDV, although males and females showed no significant difference (OR = 1.50, 95% CL 0.88-2.57 and P = 0.17). The sex of a dog has not yet been identified as a significant risk factor for GDV14,18,24,24and previous studies have not found a significant difference between intact and neutered dogs17. This study found neither sex nor status of dogs were risk factors for the development of GDV.

Although GDV syndrome can affect young dogs, the risk increases significantly with increasing age10,15. The presented data supports that previously described in the literature, that an increase in age, corresponds with an increase in the risk of developing the disease5,16Dogs older than three years have a 4.58 fold higher risk of developing GDV with the median age for GDV at 7.8 years. It has been suggested that there is an association between an increase in age and stretching of the ligaments that support the stomach which would facilitate gastric torsion when the stomach is weighed down by food6.

The occurrence of stress to the dog in the 8 hour time period before the gastric torsion-dilatation episode thus supports the theory that the dog's temperament poses a risk factor for disease17. In a comparison between large and giant breeds, large dogs with an aggressive temperament were associated with increased risk compared to dogs of a docile character. When dogs are amongst other people or animals the risk of disease is lower10. Despite the appearance that shy and aggressive, or exuberant dogs, seemed to be more predisposed to GDV development when comparing them to those with a balanced temperament, the finding was not statistically significant. However, the classification as to whether the dogs were aggressive or fearful was reliant on the owner’s assessment. Since this is subjective, a more objective method for evaluating the dog temperament would have been useful and may have produced different results. In addition to the questionnaire, it would have been useful to widen the choice of selection criteria when determining character and add other items to better define the true temperament of the subject. Finally, by increasing the sample number, it is not excluded that the association between the dog's character and the risk of illness could give positive results. The role diet plays in developing GDV has not yet been determined. For several years it has been suggested that there is an association between the consumption of commercial dry food and acute gastric dilation8,23,26. It has not been defined whether this risk is associated with; the tendency of dry biscuits to expand into the stomach, the amount of food given per meal, whether there is some other characteristic of this type of food that influences the emptying of the stomach, or a combination of all of the above 20.However, others propose that the administration of dry versus wet commercial food does not increase the risk of GDV17. This study found that dogs that were fed a diet based on commercial dry food were more likely to development of GDV in contrast to dogs that did not eat dry diets. Moreover, it has been noted that some owners moisten dry food before giving it to their dog, thinking of making the foods more palatable or softening them, thus facilitating chewing. This action was not associated with a lower risk of developing GDV in the population. Our results are in agreement with another author who states that the consumption of dry food not previously humidified before administration is a protective factor against the disease17. However, moistening dry food increases the risk of GDV in large breeds but not in giant breeds 10. Regarding other dietary habits, subjects who do not consume a mixed diet, in both commercial (dry food and / or canned wet food) and home-made (food leftovers, snacks or prizes like biscuits, bread, fruit , or food specially cooked for the dog as meat, soup, rice) are more predisposed to GDV (OR = 1.56, 95% CL = 0.84 to 2.90). Although in this study this association is not statistically valid (P = 0.2), according to some authors consuming only one type of diet represents a risk factor for GDV14. According to most of the literature data, statistically evident risk factors result in the administration of dry commercial food and the administration of wet dry food12,25,27.

One study found that having food available throughout the day increased the incidence of 13% in large sizes and 55% in giant breeds10. This was not found in this population. This study demonstrates a correlation between diet and risk of GDV. Although the combination of wet and dry food appears to protect dogs from developing GDV, this variable should be further investigated because it can be an important predisposing factor easy amendable by owners. It may be useful not only to increase the sample size, but also to record in detail the foods administered to each dog, in order to make more specific evaluations.

When environmental factors are considered, the administration of food in a bowl raised from the ground significantly increases the risk of developing GDV23. Eating from a raised bowl increases the risk of gastric torsion in large and giant dogs; 20.4% of large breed and 51.9% of giant breeds GDVs could be attributed to the use of raised bowl10 . In contrast the results of this study show that more dogs developed GDVs that had been feed from a bowl on the ground compared to dogs fed with the raised bowl. However since almost all dogs were fed with the bowl on the ground, the association between the variable and the increase in risk is subject to confounding and therefore feeding from a bowl placed on the ground may not represent a real risk factor.

The study data agrees with the finding reported in most of the literature that dogs fed only once a day are more predisposed to develop the disease compared to dogs that consume more meals in a day12,25,27. Dogs that eat quickly or voraciously had a tendency to have a greater risk of developing GDV compared to dogs that eat the meal normally or slowly, however this finding was not statistically significant.

Regarding vomiting, Elwood et Al.14 reported that, in particular Irish Setter, it has been seen that individuals affected by GDV do not report more frequent episodes of vomiting in anamnesis compared to control animals of the same sex and age. The autors concludes that, due to these data there is no significant association between vomiting and increased risk of GDV. Other authors, consider vomiting an indirect predisposing factor for the development of GDV due to the fact that it can cause aerophagia (bridal – caywood)In our study dogs that report vomiting episodes (daily, weekly or monthly) are more prone to develop GDV than dogs that do not wxhibit vomiting. In fact, there is a very significant statistical association (OR = 4,66 – CL 95%=2,67 – 8,13 and P = 0,0001). In any case, this variable should be further investigated especially as regards the causes of vomiting, the frequence of these episodes and the possible correlation with the meals. According to some authors, an increased risk of developing GDV is maily attributed to dogs that have had gastrointestinal problem in their clinical previous history 12,23. In our we did not investigated about multiple gastrointestinal problems but we studied only the relationship between previous episodes of diarrhea and GDV. From our data, dogs that report diarrhea episodes (daily, weekly or monthly) would be more predisposed to developing the disease (OR = 1.75, CL 95% = 1.02-3 and P = 0.05), even if the association is not statistically significant. The P Value, however, is at the limit to be considered statistically valid, so the study of this variable should be deepened. By increasing the sample, it is not excluded that the association between the disease and this variable could be positive. In our research we considered also the factor foreign body. Owners were asked if their dogs were used to ingest accidentally or spontaneously things other than food ( grass or foreign body). It has been seen that dogs that tend to ingest grass were more predisposed to develop GDV than dogs that do not have this feeding behaviour. The calculated values ​​(OR = 2.92, CL95% = 1.61-5.30 and P = 0.0006) testify that the ingestion of grass represents a risk factor for the GDVAbout foreign bodies a recent paper shows that there is a correlation between foreign body and development of GDV24. Our data from this research confirmed this positive association and showed a significant statistical relationship between the ingestion of foreign bodies and an increase in the risk of GDV (OR = 3.54, CL 95% = 1.97-6.36 and P = 0.02 ). According to the owners, the most ingested foreign bodies are: stones, cat litter, pieces of wood, pieces of plastic and linen (underwear, socks). Our data agree well with a recent study that states that in large and giant breed dogs, the ingestion of foreign bodies increases the risk of developing GDV by 5 times24. The theories of why the ingestion of foreign bodies could increase the risk of GDV are different24. Gastric foreign bodies can cause acute or chronic mechanical obstruction, partial or total. Obstructed outflow delays gastric emptying and can cause gastric distension. Furthermore, the presence of CE can cause gastritis. Therefore, given the serious damage that the ingestion of foreign bodies can cause, owners of dogs of predisposed breeds should restrict access to foreign material as much as possible to minimize the risk of GDV24.

Despite the complexity of the risk factors, it is possible to reduce the incidence of GDV in high-risk breeds by observing some precautions25. It is not recommended to feed the dog only once a day25. They should be fed with small amounts of food per meal and have more meals per day (at least 2)18. It would also be useful to reduce the speed of recruitment14,25, as slowing the speed of intake has a preventative effect7.

Feeding with dry commercial food alone may not be a well suited choice for dogs at risk20adding home food to the commercial diet may be useful for preventing the syndrome14. It is advisable to avoid administering only a commercial crunchy diet to those at risk14.

There are still doubts about the role of physical activity; according to some authors, the intense physical activity should be reduced in the two hours after the meal14. According to others, moderate daily physical activity and moderate post-prandial exercise appears to be beneficial for the reduction of risk20.

Owners of dogs of the breeds more predisposed to the disease should also be advised to restrict access to foreign material as much as possible, as the presence of a FB at the gastric level increases the possibility of developing GDV.

Regarding other aspects, it would certainly be useful for purebred clubs to work closely with researchers and veterinary surgeons to better identify specific morphometric and genetic factors that predispose certain dogs to the development of GDV14.

This Study Contains Several Limitations

In a case-control study, the case group and the control group are selected on the basis of the outcome (ie, having the disease of interest compared to not having the disease) and comparing the two groups with respect to their previous exposure frequencies to possible risk factors. Recruitment of subjects is specifically chosen by groups of subjects with or without the disease of interest26.

Conversely there are also advantages of this type of study. It is inexpensive, useful and effective for investigating a infrequently occurring disease. The clinician was also able to access a lot data from a single subject. Interviews with one owner granted information on signalling, eating habits and lifestyle.

Nonetheless, the case-control study is very sensitive to BIAS (or distortion). This term means the difference between the estimate obtained from the sample and the true characteristic of the population. To avoid a distortion in the identification and quantification of risk factors, it would be useful to match the cases with controls that are as similar as possible (for example the same age, sex and breed) using a procedure called "matching"26. However, in this study this type of procedure was not used and the controls were chosen on the basis of other criteria, as explained below. Furthermore it is the opinion of the authors that increasing the sample size might change final results.

Conclusion

In this study several risk factors have been identified for GDV development. These include; large and giant dogs, purebred dogs, dogs over 3 years old, a weight>30 kg, a diet which consists of commercial dry food, the ingestion of foreign bodies and grass, a history of episodes of diarrhoea and/or vomiting, exercise more than once a day and both before and after the meal, the consumption of a single daily meal and the speed of food intake.

On the contrary, neither sex nor the status of the subject (integer/neutered), temperament, BCS and the habit of long journeys or to stay in pensions or kennels are to be considered risk factors.

This study concludes that the risk of GDV in certain breeds and in certain conditions remains high. Since GDV continues to be an extremely current disease it is important that risk factors are understood. Although consideration should be given to both the complexity of the risk factors and the etiopathogenesis of GDV, the author suggests it is not possible to prevent this syndrome by acting solely on the risk factors. The only safe method to prevent the disease is preventive gastropexy27,28,29,30,31,32.

Availability of Data and Materials

All data generated or analysed during this study are included in this article.

 Consent for Publication

Not applicable

Ethics Approval and Consent to Participate:

Not applicable

Funding

The authors declare that there were no funding and support for the study.

Abbreviations

GDV - Gastric Dilatation Volvulus

SIRS - Systemic Inflammatory Response Syndrome

MODS - Multiple Organ Dysfunction Syndrome

DIC - Disseminated Intravascular oagulation

BCS - Body condition score

FB - Foreign Body

OR – Odds Ratio

ES – Effect Size

OR MIN – Odds Radio Minimal

OR MAX – Odds Ratio Maxima

TOT – Total

 M L Leary Sinnott-Stutzman V Spontaneous gastric dilatation-volvulus in two cats.Journal of Veterinary Emergency Critical Care(San Antonio)28 2018 346 355 Formaggini L Schmidt K Lorenzi D Gastric dilatation-volvulus associated with diaphragmatic hernia in three cats: clinical presentation, surgical treatment and presumptive aetiology.Journal of Feline Medicine and Surgery10 2008 2 198 201 J A Hall Canine gastric dilatation-volvulus updateSemin Vet Med Surg (Small Anim)4 1989 3 188 193 Levine M Moore G E A time series model of the occurrence of gastric dilatation-volvulus in a populationof dogs.BMC Veterinary Research5,12 2009 H J Vankruiningen L D Wojan P E Stake The influence of diet and feeding frequency on gastric function in the dog.Journal of the American Animal Hospital Association23 1987 145 153 Dudley E S Boivin G P Gastric volvulus in guinea pigs: comparison with other speciesJ Am Assoc Lab Anim Sci 2011 50 4 526 30 Kim Kyoung-Min Lee Sang-Rae Chang Kwon-Sik Lee Yong-Hoon Kim Sung-Woo Jung Kang-Jin Lee Youngjeon Kim Doo Kyu-Tae Chang (2012).Acute gastrointestinal dilation in laboratory rhesus monkeys in the Korea National PrimateResearch CenterLab Anim Res 28 3 217 221 Kim H H Park S J Park M I Moon W Acute Intrathoracic Gastric Volvulus due to Diaphragmatic Hernia: A Rare Emergency Easily OverlookedCase Rep Gastroenterol 2011 5 2 272 7 Frendin J Funkquist B Stavenborn M Gastric displacement in dogs without clinical signs of acute dilatation 1998 The Journal of Small Animal Practice 29 775 779 L T Glickman B Glickman N W &Schellenberg D Incidence of and breed-related risk factors for gastric dilatation-volvulus in 2000 dogs.Journal of the American Veterinary Medical Association216 1 40 45 C R Sharp E A Rozanski 2014 Cardiovascular and Systemic Effects of Gastric Dilatation and Volvulus in Dogs.Top Companion Animal Medicine29 67 70 Monnet E Gastric dilatation-volvulus syndrome in dogs.Veterinary 2003 Clinics of North American Small Animal 33 5 987 1005 Oron L D Klainbart S Bruchim Y Comparison of saphenous and cephalic blood lactate concentrations in dogs with gastric dilatation and volvulus: 45 cases.Canadian 2018 Journal of Veterinary Research82 4 271 277 Elwood C M Risk factors for gastric dilatation in Irish setter dogs 1998 The Journal of Small Animal Practice 39 4 185 190 Hendriks M M K E Hill Cogger N A retrospective study of gastric dilatation and gastric dilatation and volvulus in working farm dogs in New Zealand.New Zealand Veterinary 2012 60 3 165 170 Dennler R Koch D Hassig M Climatic conditions as a risk factor in canine gastric dilatation-volvulus.Veterinary 2005 Journal169 1 97 101 L T Glickman N W Glickman D B Schellenberg Multiple risk factors for the gastric dilatation-volvulus syndrome in dogs: a practitioner/owner case-control study.Journal of 1997 American Animal Hospital Association33 3 197 204 L T Glickman N W Glickman C M Pérez Analysis of risk factors for gastric dilatation and dilatation-volvulus in 1994 dogs.Journal of the American Veterinary Medical Association.204 9 1465 1471 L T Glickman Emerick T N W Glickman Radiological assessment of the relationship between thoracic conformation and the risk of gastric dilatation-volvulus in dogs 1996 Veterinary Radiology and Ultrasound 37 174 180 Raghavan M N W Glickman L T Glickman The effect of ingredients in dry dog foods on the risk of gastric dilatation-volvulus 2006 in dogs.J Am Anim Hosp Assoc.42 1 28 36 G E Moore Levine M J D Anderson Meteorological influenece on the occurrence of gastric dilatation-volvulus in dogs 2006 Journal of American Animal Hospital Association 42 1 28 36 Hullar MAJ.,Lampe J.W.,Torok-Storb B.J.. (2018)..The canine gut microbiome is associated with higher risk of gastric dilatation-volvulus and high risk genetic variants of the immune system.PLoS One.Jun 13 6 Pipan M Brown D C Battaglia C L Otto C M An Internet-based survey of risk factors for surgical gastric dilatation-volvulus in dogs 2012 J Am Vet Med Assoc 240 12 1456 62 A de Battisti Toscano M J Formaggini L(2012) Gastric foreign body as a risk factor for gastric dilatation and volvulus in dogsJ Am Vet Med Assoc Nov 241 9 1190 3 A De Battisti M J Toscano Formaggini L Gastric foreign body as a risk factor for gastric dilatation and volvulus in 2012 dogs.Journal of the American Veterinary Medical Association241 9 1190 1193 Brockman D J Washabau R J Drobatz K J Canine gastric dilatation/volvulus syndrome in a veterinary critical care unit: 295 cases (1986-1992).Journal of the 1995 American Veterinary Medical Association207 4 460 464 Schellenberg D Yi Q N W Glickman Influence of thoracic conformation and genetics on the risk of gastric dilatation-volvulus in Irish setter 1998 Journal of American Animal Hospital Association 34 1 64 73 Broome C J Walsh V P Gastric dilatation-volvulus in dogs 2003 New Zeland Veterinary Journal 51 6 275 283 Jekel&apos;s Epidemiology, Biostatistics, Preventive Medicine, and Public Health.4th Ed.Elsevier 2013 Mosby,Saunders, Netter & More; 145 176 Dujowich M M E Keller S B Reimer Evaluation of short- and long-term complications after endoscopically assisted gastropexy in 2010 dogs.Journal of the American Veterinary Medical Association236 2 177 182 Rawlings CA,Mahaffey MB,Bement S,Canalis C 2002 1576 81 M P Ward G J Patronek L T Glickman Benefits of prophylactic gastropexy for dogs at risk of gastric dilatation-volvulus.Preventative 2003 Veterinary 60 4 319 329