Heat Tolerance of Siberian Husky Dogs Living in Brazil: A Case Study on the Perceptions and Attitudes of Their Owners.

The management of the thermal environment to which dogs are exposed should be included in strategies to improve their welfare. An online questionnaire was administered to 624 owners of Siberian Husky dogs residing in Brazil, with the objective of assessing their perceptions regarding their dogs' capacity to adapt to heat, and its association with the owners' routine care. Owners who believed that dogs are low-heat-tolerant animals were more likely to report heat response behaviors from their dogs. Overall, owners reported walk with their dogs during early morning, late afternoon and nighttime. They also reported solar radiation as the primary criteria for determining the time to walk with their dogs. However, owners who reported walking with their dogs at noon mentioned time availability as their primary criteria. In conclusion, owners perceive Siberian Husky dogs living in Brazil as being poorly adapted to heat, and this perception appeared to influence their positive attitudes towards protecting their dogs from heat stress by choosing to walk them during times with less solar exposure. However, the lack of time for owners to walk with their dogs during cooler periods can still be a risk factor in exposing the animals to extreme hot conditions.

Conditioning Program Prescribed from the External Training Load Corresponding to the Lactate Threshold Improved Cardiac Function in Healthy Dogs.

This research focuses on the adjustments in systolic and diastolic functions that are not fully understood in dogs submitted to athletic training. Beagle dogs carried out an endurance training program (ETP) prescribed from the external training load, corresponding to 70-80% of the lactate threshold (VLT) velocity. Eighteen dogs were randomly assigned to two groups: control (C, n = 8), active dogs that did not perform any forced exercise, and trained (T, n = 10), submitted to the ETP during eight weeks. All dogs were evaluated before and after the ETP period using two-dimensional echocardiography, M-mode, Doppler, and two-dimensional speckle tracking. A principal component analysis (PCA) of the echocardiographic variables was performed. The ETP improved the left ventricular internal dimension at the end of diastole (LVDd), the left ventricular internal dimension at the end of diastole to aorta ratio (LVDd: Ao), and the strain rate indices. PCA was able to capture the dimensionality and qualitative echocardiography changes produced by the ETP. These findings indicated that the training prescribed based on the lactate threshold improved the diastolic and systolic functions. This response may be applied to improve myocardial function, promote health, and mitigate any injuries produced during heart failure.

The effects of age and dietary resistant starch on digestibility, fermentation end products in faeces and postprandial glucose and insulin responses of dogs.

The same food formulation processed to obtain two different starch gelatinisations (SG) and resistant starch (RS) contents was evaluated in old and adult dogs, regarding apparent total tract digestibility (ATTD) of nutrients, fermentation products in faeces, and postprandial glucose and insulin responses. A diet with corn was ground and extruded in two different ways, obtaining Low RS (2.2 g/kg DM; 99.9% of SG) and High RS (15.3 g/kg DM; 62.6% of SG). Each diet was fed to adults (4.0 ± 0.7 years) or old beagle dogs (11.5 ± 0.4 years) in a 2 (ages) x 2 (RS amounts) factorial arrangement with 8 dogs per food. Data were evaluated by analysis of variance, and postprandial responses by analysis of variance of repeated measurements over time (p < 0.05). Diet × age interaction was observed for protein ATTD, with lower values for old dogs fed High RS than those for the other treatments (p < 0.05). No age or diet effect was verified for the ATTD of other nutrients and faecal score. Faecal moisture and pH were higher for adults than that for old dogs (p < 0.05). The High RS food increased acetate, propionate and butyrate concentrations in faeces, regardless of age (p < 0.01). Old dogs presented lower acetate and total short-chain fatty acids (SCFA) and higher lactate and ammonia than adults (p < 0.05). Only for old dogs the intake of the High RS food reduced ammonia and increased faecal lactate (p < 0.05). An age × diet interaction was verified for glucose postprandial response, with lower values for old dogs fed High RS food (p < 0.05), while no differences were found for the other treatments. Old dogs had higher postprandial insulin secretion regardless of the diet (p < 0.05), and lower insulin increment at 180 min after the meal when fed the Low RS than when fed the High RS food (p < 0.05). In conclusion, the diet with lower SG and higher RS improved the intestinal microenvironment, with higher butyrate and total SCFA without altering faeces production or score. Old dogs presented less acetate and total SCFA and higher lactate and ammonia in faeces than adults. The High RS food increased lactate and reduced ammonia in faeces of old dogs, with possible positive influences for gut health. Old dogs had higher postprandial insulin secretion than that of adults to maintain blood glucose, and the diet with higher RS content reduced the postprandial glucose response of old dogs.

Starch and fibre intake and glucose postprandial response of dogs / Consumo de amido e fibra e a resposta pós-prandial de glicose de cães

ABSTRACT: Fibre has been studied to reduce the postprandial glucose response of dogs, but the results are inconsistent. Starch intake, however, was not properly considered in the published studies. The effects of starch and fibre intake on the postprandial glucose response were studied in non-obese adult dogs. Cellulose (CEL), carboxymethylcellulose (CMC), pea fibre (PE) and sugarcane fibre (SCF) were combined to form six diets with starch contents ranging from 33% to 42%: SCF+CEL and PE+CEL diets, both with high insoluble fibre (IF=22%) and low soluble fibre (SF=2.5%) content; SCF+CMC and PE+CMC diets with high SF (SF=4.5%; IF=19%) content; and CMC and CEL diets with low dietary fibre (14%) content. The diets were fed in two amounts, providing an intake of 9.5g or 12.5g of starch (kg0.75)-1 day-1, totaling 12 treatments. Each diet was fed to six dogs conditioned to consume all of the daily food in 10min. Their plasma glucose levels were measured before and during 480min after food intake. Results of fibre and starch intake and their interactions were compared by repeated measures ANOVA and the Tukey test (P<0.05). Fibre intake did not change the glucose postprandial responses (P>0.05). High-dose starch intake, however, induced a higher glycaemia at 180 and 240min after the meal and a greater maximal glycaemia and greater area under the glucose curve (P<0.05). A range in insoluble and soluble fibre intake does not change postprandial glucose response, and the amount of starch intake is a main factor for the postprandial glucose response of healthy non-obese dogs.

RESUMO: Fibras têm sido estudadas como opção para reduzir a resposta glicêmica pós-prandial de cães, mas os resultados obtidos têm sido inconsistentes. A ingestão de amido, no entanto, não tem sido adequadamente considerada na interpretação dos resultados de algumas dessas pesquisas. O presente estudo investigou, em cães adultos não obesos, os efeitos da ingestão de amido e fibra sobre a resposta pós-prandial. Celulose (CEL), carboximetilcelulose (CMC), fibra de ervilha (PE) e fibra de cana-de-açúcar (SCF) foram combinadas, gerando seis dietas com 33% a 42% de amido: dietas SCF+CEL e PE+CEL com alta fibra insolúvel (IF=22%) e baixa fibra solúvel (SF=2,5%); dietas SCF+CMC e PE+CMC com alta fibra solúvel (SF=4,5%; IF=19%); dietas CMC e CEL como controles baixa fibra (14%). As dietas foram fornecidas aos cães em duas quantidades, resultando na ingestão de 9,5g ou 12,5g de amido (kg0,75)-1 dia-1, gerando um total de 12 tratamentos. Cada tratamento foi fornecido a seis cães, condicionados a ingerir todo o alimento do dia num período de 10min. A glicose plasmática foi medida em jejum e durante 480min após a refeição. Os resultados foram analisados por análise de variância de medidas repetidas, considerando-se os feitos da ingestão de amido e fibra, e suas interações, sendo as médias comparadas pelo teste de Tukey (P<0,05). A ingestão de fibra não alterou a resposta pós-prandial de glicose (P>0,05). O consumo da dose elevada de amido, no entanto, resultou em maiores glicemias aos 180 e 240min, maior glicemia máxima e maior área abaixo da curva de glicose (P<0,05). Verificou-se que a quantidade ingerida de amido é mais importante que o consumo de fibra para a resposta glicêmica pós-prandial de cães não obesos.

Microminerais complexados a aminoácidos no desempenho reprodutivo de matrizes pesadas e resposta da progênie / Complexed trace minerals to amino acids on broiler breeders reproductive performance and response from progeny

Este estudo teve como objetivo avaliar o uso de microminerais complexados a aminoácidos na alimentação de matrizes de frango de corte sobre o desempenho, variáveis de incubação e desempenho da progênie. O estudo foi dividido em três experimentos: exp.1. desempenho das matrizes, exp.2. incubação e exp.3. desempenho da progênie. No exp. 1, foram utilizadas 260 aves da linhagem CobbAvian 48 (240 matrizes e 20 machos), avaliando-se produção e massa de ovos, conversão alimentar por massa e por dúzia de ovos, peso e gravidade específica. No exp. 2, determinou-se a taxa de eclosão, eclodibilidade e fertilidade. No exp. 3 avaliou-se o desempenho dos pintinhos nascidos das incubações. No exp. 1, não houve interação entre tratamento e período (P>0,05) para produção de ovos, massa de ovos, conversão alimentar por massa e por dúzia de ovos, peso e gravidade específica dos ovos. Contudo, houve efeito (P<0,05) do período para todas as variáveis citadas anteriormente. No exp. 2, a taxa de eclosão, fertilidade e eclodibilidade não apresentaram diferenças significativas (P<0,05). Com relação ao exp. 3 também não houve diferença significativa (P<0,05) no desempenho da progênie. A suplementação com microminerais complexados a aminoácidos não influencia no desempenho das matrizes, variáveis de incubação e desempenho das progênies.

This study aimed to evaluate the use of complexed trace minerals to amino acid in broiler breeder feeding evaluating performance, incubation variables and performance of progeny. The study was divided in three trials: exp. 1. broiler breeders performance, exp. 2. incubation and exp. 3. chickens performance. In the exp. 1 two hundred sixty broilers breeders of lineage Cobb Avian 48 (240 females and 20 males) were used. The variables evaluated were egg production and egg mass, feed conversion for egg mass and per dozen eggs, egg weight and specific gravity. In the exp. 2 it was determined rate of hatching, hatchability and fertility. In the exp. 3, it was evaluated the performance of chicks born from incubations. In the exp. 1, there was no interaction between treatment and period (P>0.05) for egg production, egg mass, feed conversion for egg mass and per dozen eggs, egg weight and specific gravity of eggs. However, there was effect (P<0.05) of the period for all variables mentioned above. In the exp. 2, hatching rate, fertility and hatchability did not show significant difference (P<0.05). Regarding the performance of broilers, in the exp. 3 there was no significant difference (P<0.05). Supplementation with complexed trace minerals to amino acids does not influence the performance of breeders, incubation variables and progeny performance.