Dog obesity: veterinary practices' and owners' opinions on cause and management.

Obesity in dogs is attributed to several factors, including genetic pre-disposition, reproductive management and dietary/exercise (human) management. A quantitative analysis of questionnaire responses from dog owners and veterinary practices in Victoria, Australia was used. A total of 219 dog owner questionnaire and 153 veterinary practice questionnaires were returned. Veterinary practices estimated the prevalence of dog obesity within their practice as 30% on average, ranging from <10 to 100%. Veterinary practices felt that 3% of cases could be attributed to dog specific factors and 97% to human specific factors such as diet, exercise and owner attitudes. Management strategies included reducing food intake, reduced treat feeding and changing diet before recommending more intensive options such as obesity clinics. Of the surveyed veterinary practices, 43% ran obesity clinics and 79% of those believed they were a valuable management tool. Of veterinary practices that did not run obesity clinics, only 46% believed them to be a valuable management tool. Dog owners preferred to try to reduce dog weight through diet manipulation, increasing exercise and elimination of treats prior to consulting the veterinary practice. There is a clear difference in expectations with veterinary practices recommending reduction in dietary intake compared to owners expecting to have to modify the diet itself, which may have a cost and hence psychological implication to the owner.

Dog obesity: owner attitudes and behaviour.

Animal (dog) factors that contribute to obesity are classified into three broad categories: genetic pre-disposition, reproductive management and dietary/exercise (human) management. This paper examined the latter-dietary/exercise (human) management. A quantitative analysis of questionnaire responses from dog owners and veterinarians was used to determine the routine care and obesity management strategies for dogs. A total of 550 questionnaires were distributed to dog owners in Victoria, Australia. Owners were asked to score the body condition of their animal by comparison with photographic images of animals with condition score ranging from 2 to 5. The management routines of 219 dog owners were received, including data on 302 dogs. There were 168 households with normal weight animals (BCS 2 and 3) and 51 with obese animals (BCS 4 and 5). The mean number of people per household (normally involved with caring for the animal(s)) with normal weight dogs was significantly lower than that of households with dogs categorised as overweight or obese (Kruskal-Wallis, Chi; chi(2)=6.28; 2.2 (s=0.79) vs. 2.5 (s=1.66); d.f.=2, P<0.05). Dog owners identified a preference for main meal feeding of 'twice a day' (60%), followed by 'once daily' (33%), 'greater than or equal to three times daily' (2%), and 'always feed available' (5%). There was a significant difference (Chi; chi(2)=6.30; d.f.=1; P<0.05) in the frequency of main meal feeding between households. Normal weight animals had food divided into two portions, whereas obese animals or animals from mixed households were more often fed their meal in either one or three-plus portions. Almost all owners fed treats (99%) in the daily feed. Households with normal weight dogs gave treats significantly less frequently than households with obese or mixed weight dogs (Chi; chi(2)=31.81; d.f.=6; P<0.001). The frequency of exercise differed between households (Chi; chi(2)=9.9; d.f.=1; P<0.01), with normal weight dogs being exercised daily compared to weekly for overweight or mixed weight dogs. Owners who indicated that their dog was confined to a yard as its exercise regime rather than walked were also significantly more likely to be an obese or mixed weight household (Chi; chi(2)=18.4; d.f.=1; P<0.001). In conclusion, there is clear evidence that obesity in dogs is affected by the interrelationships between food management, exercise and social factors.

Relationships between fatty acid status of sow plasma and that of umbilical cord, plasma and tissues of newborn piglets when sows were fed on diets containing tuna oil or soyabean oil in late pregnancy.

To investigate the relationships between maternal, umbilical cord and piglet fatty acid status, multiparous sows (six per diet) were fed on diets containing supplements (30 g/kg) of either soyabean oil or tuna oil for the last 21 d of pregnancy. The proportions of most fatty acids differed between diets: in particular, the tuna-oil-containing diet supplied more 22:6n-3 and less 18:2n-6 fatty acids than the soyabean-oil-containing diet. Maternal plasma fatty acid concentrations (mg/l) were greater than those in umbilical plasma and 20:4n-6 and 22:6n-3 fatty acids were present in higher proportions (g/100 g fatty acids) in umbilical than maternal plasma. Feeding tuna oil increased the proportionate amounts (g/100 g fatty acids) of total n-3 fatty acids (particularly 22:6n-3) in umbilical cord, plasma and piglet tissues compared with feeding soyabean oil: in contrast, the proportion of 20:4n-6 was decreased by feeding tuna oil. Changes in piglet fatty acid proportions as a result of oil feeding were not influenced by piglet weight. While proportions of the long-chain n-3 and n-6 polyunsaturated fatty acids in piglet liver, spleen and reproductive tract (ovaries plus uterus of the female, testes of the male) correlated well with those of umbilical plasma, those in brain and retina were poorly correlated. Therefore umbilical plasma cannot be used to predict the fatty acid status of piglet brain.

Effect of feeding tuna oil or soyabean oil as supplements to sows in late pregnancy on piglet tissue composition and viability.

To investigate whether long-chain n-3 polyunsaturated fatty acids could cross the porcine placenta in late pregnancy and alter neonatal piglet tissue composition, multiparous sows (seven per diet) were fed on diets containing a supplement (30 g/kg) of either soyabean oil or tuna oil for the last 21 d of pregnancy and the first 7 d of lactation. The proportions of all fatty acids, except 18:1n-7, differed between diets: in particular, the tuna-oil-containing diet supplied more 22:6n-3 and less 18:2n-6 fatty acids than the soyabean-oil-containing diet. The proportions of n-3 fatty acids, particularly 22:6n-3 (g/100 g total fatty acids) in sow plasma, colostrum and milk were increased and the proportion of 18:2n-6 was decreased by feeding tuna oil. Piglet tissue n-3 fatty acid proportions (particularly 22:6n-3), obtained shortly after birth, were increased in piglets born to tuna-oil-fed sows compared with progeny of soyabean-oil-fed sows. The increase in the proportion of n-3 fatty acids (g/100 g total fatty acids) in piglet tissues as a result of tuna-oil feeding, compared with soyabean-oil-feeding, was in the order plasma > liver > erythrocytes > spleen > brain > retina. Piglets born to tuna-oil-fed sows had a lower viability score at birth than the progeny of soyabean-oil-fed sows. The proportions of long-chain n-3 fatty acid in tissues of new-born piglets were increased by feeding tuna oil to the sow in late pregnancy; however no improvements in piglet viability were observed.