Research On Energy And Protein Requirement For 5～10 Week Yangzhou Goose

Experiments were conducted to investigate the effect of different dietary metabolizable energy (ME) and crude protein(CP) levels on growth performance, carcass performance and blood parameters in 5¹0 week Yangzhou goose, by rearing, comparative slaughter and metabolism experiments. It also could conclude the ME and CP requirement for maintenance and the ratio of them in diet.1. A 3×3 factorial experiment was conducted with 180 28-day-old Yangzhou goslings to investigate the requirement of ME and CP, which took ME and CP as the two factors. The results showed that: (1) There were no significant difference among groups in body weights (BW) of 10 weeks and daily gain(P>0.05). At low and middle levels of CP, the BW increased with the ME increasing. Nevertheless, the BW decreased with the ME increasing at the high level of CP. And the BW decreased with the CP increasing at the middle and high levels of ME. The daily gain also decreased with the CP increasing at the middle and high levels of ME. The daily feed consumption generally decreased with the ME and CP increasing. The feed conversion decreased with the ME increasing at low, middle and general levels of CP. The effects of ME, CP and interaction between them were interaction>ME>CP. Only interaction could significantly effect daily gain (P<0.05). (2) The ME and CP had no significant effect on eviscerated carcass weight rate, breast muscle rate and sebum rate (P>0.05), but had significant or very significant effect on the leg muscle rate and the abdominal fat rate. The abdominal fat rate increased with the ME increasing at the low, middle and general levels of CP. The ME had more effect than the CP on the five carcass parameters. (3) The ME and CP had no significant effect on TP, Alb and GH (P>0.05), but had significant or very significant effect on TG, Glu, BUN and UAC. TG, BUN and UAC all increased with the CP increasing. Glu increased with the ME increasing, but UAC decreased with the ME increasing. The interaction had very significant effect on Glu and GH (P<0.01) and significant effect on BUN (P<0.05). At comprehensive consideration of growth performance, carcass performance and blood parameters, 10.50MJ/kg and 17% were respectively recommended as ME and CP levels in 5¹0 week Yangzhou goose.2. This experiment was conducted to investigate the effect of different ME and CP levels on body composition, ME and CP deposition, ME requirement. At the beginning of the test, 4 birds (2 male and 2 female) were slaughtered as the contrast. And at the end of the test, 36 birds, selected from 9 groups(4 in each group, 2 male and 2 female) in rearing test according to the BW, were also slaughtered to compare the contrast. The result showed that: (1) The ME had very significant or significant effect on body composition. The fat and energy content in the carcass increased with the ME increasing, but the water and protein content in the carcass conversely decreased. However, the CP had no significant effect on the body composition(P>0.05). (2) The protein intake increased with the CP increasing, but the protein deposited content and rate conversely decreased. The ME intake, ME deposited content and rate all increased with the ME increasing. (3) ME requirement for maintenance was 604.78 KJ/W0.75 and ME requirement in dietary was 11.53MJ/kg.3. This experiment was conducted to determine the CP requirement for maintenance (Ncp) and the ratio of CP in diet. At 63d old, 16 goslings were used in a nitrogen(N) balance test with an N-free diet. The birds were divided into 4 equal groups and offered an N-free diet at intakes of 90, 70, 50 and 0 g per d, respectively. The results showed that: (1) Nm showed a significant negative correlation with the intake of N-free diet (P< 0.05). (2) Ncp was 191.2mg/kg BW0.75 and the ratio of CP in diet was 20.66%.4. In summary, the ME and CP requirement formulas for 5¹0 week Yangzhou goose were: ME=604.78 W0.75 + 28.84â–³W; CP=5.60W^0.75 + 0.78â–³W. ME and CP requirement for maintenance were 604.78 KJ/W0.75 and 5.60 g/kg BW0.75.