Effects of Low Crude Protein Diets Supplemented With Amino Acids on Slaughter Performance and Composition of Breast Muscle of Mule Ducks
This experiment was conducted to study the effect of low crude protein ( CP) diets supplemented with amino acids on slaughter performance and composition of breast muscle of Mule ducks. A total of 450 one-day-old Mule ducks were randomly assigned to 3 groups with 5 replicates and 30 ducks in each replicate ( 50% males, 50% females) . The control group received the diet included the normal level of CP ( 19% CP during 1 to 21 days of age, 16% CP during 22 to 56 days of age) , and the level of CP in diets of experimental group Ⅰ and experimental group Ⅱ were decreased by 1% and 2%, respectively, while supplied with com-pounded amino acids. The feeding trial lasted for 56 days. The results showed as follows:1) there was no sig-nificant effect on slaughter performance of ducks included slaughter rate, carcass yield rate, abdominal fat rate, leg rate, leg muscle rate, breast muscle rate, lean meat rate and subcutaneous fat rate at 56 days of age ( P>0.05) . 2) Compared with the control group, the content of crude fat in breast muscle of ducks at 56 days of age was significantly increased by 10.9% and 28.3% associated with the descending of CP level in feed by 1%and 2% ( P<0.05) , meanwhile, the content of CP in breast muscle of ducks at 56 days of age was decreased by 1.1% and 2.5%, respectively ( P<0.05);most of amino acid contents in breast muscle of ducks among all groups had no obvious difference ( P>0.05) , but Met and Met+Cys contents in breast muscle of female ducks in experimental group Ⅱ were significantly decreased (P<0.05). These results indicate that dietary CP de-creased by 1% to 2% have no obvious effects on growth performance, slaughter performance and most of ami-no acid contents in breast muscle of Mule ducks, but can significantly increase the crude fat content and de-crease CP content of breast muscle under the condition that amino acid in diet meet the need of birds.
国家科技期刊平台
NSTL
万方数据
维普
