Crescimento e desenvolvimento de filhotes de cães da raça Australian Cattle Dog

Abstract

The Australian Cattle Dog (ACD) is a robust and muscular working dog, classified in group I of the International Cynological Federation. The aim of the studies was to analyze parents and pups in the first 45 years of life, relating the data obtained with the mortality and growth of puppies of the breed in the neonatal period through relationships between growth, birth weight, average number of pups in the litter and weight gain. weight of puppies of the breed in the first 45 days and also to describe through parameters the relationship between birth weight, weight gain and the inbreeding coefficient (CoI), and the mortality observed in the neonatal period. Puppies were weighed at birth and up to 45 days of age. Litter effects were compared using the Tuckey test (p≤ 0.05). To establish the growth behavior of each of the groups, the average weight of the pups in relation to the days of weighing were adjusted through the regression model and Pearson's Correlation between the variables was calculated. The groups also had birth weight heterogeneity, average daily weight gain and CoI of each litter calculated, followed by obtaining the quartiles for the variables. Multicollinearity was estimated between the predictors using Cramer's method and the median area under the receiver operating characteristic curve (AUROC). The bitchs were aged between 18 and 70 months and the average weight of the mothers at the time of mating was 13.5+- 1.4 kg (ranging from 10.4 to 16.7 kg) and the average weight of the fathers was 16, 05+-1.67Kg, (ranging from 13.1 to 18.5Kg). 17 litters born in 2020 were included, totaling 100 puppies, 54 males and 46 females. The mean number of pups per litter was 5.88 +- 1.93 and mean birth weight was 258.98+-47.19g. The average daily weight gain in the different groups was more strongly related to the average birth weight and moderately to the mother's weight and weakly related to the father's weight. The average daily weight gain of the offspring of the eight groups analyzed during the first 45 days of life ranged from 60.12 to 40.16g. The validity of the relationship between mortality in the neonatal period and the fact of the mother being primiparous (AUROC≥0.7) was observed. Simple measures such as weighing and monitoring pups through growth curves should be implemented, intensifying attention in large litters, heterogeneous and first-birth females.