Modelling Growth Curve Of Eastern Spot-Billed Ducks (Anas Zonorhyncha) Raised In Vietnam

The Eastern spot-billed ducks (Anas zonorhyncha) are raised as backyard duck in Vietnam. Improvement of the growth performance of this breed is important for duck production in rural areas in Vietnam. Little is known about the performance and growth curves of this breed. In this study, six growth models (Gompertz, Brody, Logistic, Richards, Bridges and Janoschek) were used for a modelling growth curve. The body weight of 92 ducks was recorded weekly from the 1st to the 14th week of age. The minpack.lm package in R software was used for fitting the models, and Akaike's information criterion (AIC) and Bayesian information criterion (BIC) were used for model comparison. Based on their criteria, the Gompertz and Brody models were the best and the worst ones, respectively, regardless of sexes. Estimated asymmetric weights (alpha) ranged from 1179 +/- 9.24 g (Logistic model) to 1397 +/- 26.3 g (Brody model) for males and from 1048 +/- 6.92 g (Logistic model) and 1222 +/- 19.28 g (Brody model) for females, respectively. Age at inflection point was estimated from 3.58 to 4.58 weeks for males and from 3.48 to 4.46 weeks for females, respectively. The growth patterns were different between males and females. So, the possibility of using the Gompertz growth model for modelling the growth of Eastern spot-billed ducks was shown. Obtained information on the growth characteristics of Eastern spot-billed ducks might be used for management strategies and further genetic or genomic research.