Diet metabolisability and performance of slow-growing chickens fed with cottonseed cake

Abstract

The aim of this study was to evaluate poultry performance and diet metabolisability in slow- growing naked neck chickens fed different substitution levels of soybean meal protein with cottonseed cake protein. The trial was conducted in a completely randomized design with five treatments (0, 10, 20, 30 and 40% substitution of soybean meal protein with cottonseed cake protein), six replicates and fifteen birds per replicate. The birds and diets of each experimental unit were weighed at one day old. At 30, 60 and 85 days old, the chickens and leftovers were weighed again to estimate the feed intake (FI), weight gain (WG), feed conversion (FC) and final weight (FW) from 1 to 30 days, from 1 to 60 days and from 1 to 85 days old. To evaluate diet metabolisability, a three-day total excreta collection (26 to 28 days of age) was performed. A quadratic effect was reported for diet metabolisability, in which the minimum substitution level was 17.45% and 17.69% for apparent metabolisable energy (AME) and nitrogen-corrected apparent metabolisable energy (AMEn), respectively. Based on performance, it is recommended to replace 40% soybean meal protein with cottonseed cake protein.