摘要：The present study aimed to compare impact of various methods of raising protocols on some traits of Pekin ducks under hot climate conditions.A total number of 250,one day old Pekin ducks,were weighed and randomly divided into three experimental groups; the first group (G1) was reared indoor and fed a commercial diet only,the second (G2) was reared indoor and fed the commercial diet with grass,and the third group (G3) was fed on commercial diet with outdoor grass feeding i.e.free range system.Live body weight,weight gain,growth rate,consumption,feed conversion,carcass traits,mortality rate and defects were recorded.Sexual dimorphism was calculated for live body weight and carcass traits.Our results indicate that G3 ducks had significantly heavier live body weight at 1and 5 wks of age compared to other two groups.Feed conversion ratio was better in G3 (1.80) followed by G1 (1.93) and then G2 (2.01) from 1-6 weeks of age.Females had significantly higher relative edible meat parts compared to males.G2 had significantly lower sexual dimorphism for live body weight,dressed carcass,giblets and edible meat parts compared to other groups.The G3 show better productive and economic efficiency than other raising systems.Finally,we conclude that the third group (G3) that fed on commercial diet with outdoor feeding of ducks on grass or free range system could be applied as practical and beneficial protocol,in terms of better live body weight,feed consumption,feed conversion ratio,lowest feed cost and better economic efficiency compared to other studied groups.In addition,it may be a potential for improving the welfare of duck flocks.
