| A 2×5 factorial experiment which has the same protein/energy ratio containing two energy (MJ/kg) and CP(%) levels and five lysine levels was conducted to evaluate the effects of dietary energy and protein on lysine requirement of early Beijing ducklings and the effect of lysine on growth performance , growth of some tissue and organ ,biochemical index of insrum and fat metabolism. There were two energy and protein levels which were 10.91MJ/kg,18% and 12.12 MJ/kg,20%.The protein/energy ratio were 0.61:1((MJ/kg) /%).The five lysine levels were 0.65%, 0.80%, 0.95%, 1.10%, 1.25%. Five hundred and sixty 8-day-old male White Beijing ducklings were divided to 10 experimental treatments, each containing 8 replicate pens with 7 birds per pen. These ducklings were raised with feed and water provided ad libitum from 8 to 21 days of age. At 21 days of age, Beijing ducklings were weighted to measure the growth performance and then twelve ones of each treatment were blooded and slaughtered to measure the growth of some tissues and organs and some biochemical indexes in plasma.The result of two experiments were as follow:1. The result of rearing trail(1) ME,CP had a significant effect on feed intake and feed conversion efficiency(P<0.05). Compared with ducklings fed 10.91MJ /kg enenrgy and 18% CP diets, feed intake,feed conversion efficiency and daliy lysine intake of birds fed 12.12 MJ /kg energy and 20% CP diets was reduced significantly but dietary energy and protein had no significant effects on weight gain and daily energy and CP intake of birds(P>0.05).Lysine had a significant effect on weight gain and feed conversion efficiency(P<0.05).(2) At high energy and protein level ,energy and CP intake of early Beijing ducklings were1.71MJ/bird and 28.30g/bird. At low energy and protein level ,energy and CP intake of early Beijing ducklings were1.70MJ/bird and 28.05g/bird.The RSD were 0.3% and 0.4%.There were no difference.The daily energy requriment of Beijing ducklings is 1.705 MJ/bird. The daily protein requriment of Beijing ducklings is 28.175g/bird.(3) With the increasing of levels of dietary lysine,the daily lysine intake of Beijing ducklings increased signigicantly(P<0.05). the feed conversion efficiency decreased signigicantly(P<0.05)。High levels of lysine improved weight gain significantly of early Beijing ducklings(P<0.05). At high energy and protein level, With the increasing of levels of dietary lysine,the daily weight gain ,feed intake , weight,breast weight of Beijing ducklings increased signigicantly(P<0.05). the feed conversion efficiency decreased signigicantly(P<0.05)。At low energy and protein level, With the increasing of levels of dietary lysine,the daily weight gain , weight, breast weight of Beijing ducklings increased signigicantly(P<0.05). the feed conversion efficiency decreased signigicantly(P<0.05)。However,there is no effect on feedintake(P>0.05).(4) According to growth performance and breast weight.There were four methods (quadrtic analysis , broken line regression model with quadratic , broken line regression model with linear and t-test) evaluate the lysine requirements of Beijing ducklings from 8 to 21 days of age.The lysine requirement estimated by quadratic analysis regression analysis for daily weight gain were 1.06% and 0.94%. At high energy and protein level, the lysine requirement estimated by quadratic analysis regression analysis for feed/weight was 1.07%. At low energy and protein level, the lysine requirement estimated by broken line with liner regression analysis for feed/weight was 0.81%. At high energy and protein level, the lysine requirement estimated by broken line with liner regression analysis for breast weight was 0.91%.(5) It was concluded that lysine requirement should be increased when dietary energy and protein are increased. At different level of CP and energy , the lysine daily absolute requirement was 1.485g/bird/day.2. Effects of ME,CP and lysine on the growth of some tissues and organs of early Beijing ducklingsLysine rasied the weight of breast meat,leg meat ,heart,,liver and the breast meat percent of body weight of early Beijing ducklings(P<0.05),decreased the abdominal fat percent of body weight With increasing of the levels of dietary CP and ME,the body weight ,liver weight,breast meat yield and its percentage of body weight increased significicantly(P<0.05).3. Effects of ME,CP and lysine on the biochemical indexes of early Beijing ducklingsWith increasing of the levels of dietary CP and energy, the albumin significant decreased,increased the total protein,urea acid and FFA(P<0.05). Lysine decreased the weight of abdomial fat,fat of liver ,TC,FFA, of early Beijing duckling(sP<0.05). With increasing of the levels of dietary CP and ME, Fat of liver significant decreased,FFA in plasma significant increased(P<0.05).The album and total protein in the lysine level of 0.65% period is significant lower than other lysine periods(P<0.05).
|
PDF Full Text Request