Chanwit KaewtapeeKriengkrai PrahkarnkaeoChaiyapoom BunchasakKasetsart University. Faculty of Agriculture. Department of Animal ScienceMahidol University. Faculty of Veterinary Science. Department of Clinical Sciences and Public Health2020-04-022020-04-022020-04-022018Journal of Applied Animal Science. Vol.11, No.2 (May- Aug 2018), 9-18https://repository.li.mahidol.ac.th/handle/20.500.14594/53990The objective of this study was to determine the effect of sex dimorphism on growth curve, production performance and carcass quality of Cherry valley ducks. Fifteen male and fifteen female ducks were randomly kept in an individual metabolic cage under evaporative cooling system. Ducks were fed with a starter-1 diet (22.00% crude protein [CP], and 2,850 metabolizable energy [ME] kcal/kg) from 1 to 9 days, a start-2 diet (20.00% CP and 2,900 ME kcal/kg) from 10 to 16 days, a grower diet (18.50% CP and 2,900 ME kcal/kg) from 17 to 42 days, and a finisher diet (16.99% CP and 2,950 ME kcal/kg) from 43 to 49 days. Water and feed were offered ad libitum throughout experimental period. The Gompertz model was used to develop the growth curve for male and female ducks. A two-sample t-test was used to compare the effect of sex dimorphism on production performance and carcass quality. The results showed that there were significant differences (P<0.05) in body weight (BW), average daily gain and feed intake between male and female ducks from 42 days. The accuracy of R2with Gompertz equations was 0.9907 and 0.9857 for male and female ducks, respectively. For carcass quality and internal organs at 49 days of age, male ducks had greater skeleton, breast meat, feet and gizzard (P<0.05), whereas female tended to have greater (P=0.10) skin with subcutaneous fat. In conclusion, since the sex dimorphism of ducks showed significant effect on growth rate from 42 days of age, the separate sex growing should be considered to obtain the uniformity of BW and carcass quality of Cherry Valley ducks.engMahidol UniversityCarcass qualityCherry Valley duckGrowth curvePerformanceSexJournal of Applied Animal ScienceResearch ArticleFaculty of Veterinary Science Mahidol University