Influence Of Stocking Density And Cage Size On Growth Performance、Immune Stress And Animal Welfare Of Broilers

Animal welfare is now a hot research, Cage size and stocking density have great influence on the welfare of broilers.This experiment was conducted to study the influence of stocking density and cage size on broilers from net rearing and battery rearing, as well as to exPlore the feasibility of net rearing, Provide a theoretical basis for the actual Production. This research mainly from the Production Performance, meat quality, antioxidant function, behavior, and other asPects of immunological stress to do the exPeriment.Test is divided into three Parts, The first exPeriment to exPlore the influence of stocking density and cage size on the broilers of net rearing.Using a 3x2 factors completely randomized design,756 one-day old broilers (AA+) were allotted randomly into 6 grouPs, each with 6 rePlicates. Two activity sPaces:were designed as 2.88m~2(2.4×1.2m) and 1.44 m~2(2.4×0.6m~2),3stocking densities were designed as:high density(14/m~2),modest density(10/m~2)and low density(6/m~2).The second exPeriment to exPlore the influence of stocking density and cage size on the broilers of battery rearing.Using a 3×2 factors completely randomized design,270 one-day old broilers (AA+) were allotted randomly into 6 grouPs, each with 6 rePlicates. Two activity sPaces:were designed as0.7 m~2(0.7×1m~2)and 1.44 m~2(0.7×0.5m~2),3 stocking densities were designed as:high density(18/m~2),modest density(14/m~2)and low density(10/m~2).The third exPeriment to exPlore the influence of stocking density and rearing system on the broilers.Two rearing systems:net rearing and battery rearing,2 stocking densities were designed as:high density(14/m~2)and low density(10/m~2).The results showed that:Lnet rearing:cage size and stocking density have a significant interaction on ADG andABW (P<0.05).The ADG andABW of medium density large-size grouP (2.88 m~2,10/m~2) was highest in all grouPs all the time,and F/G was lowest.survival rate of large size was higher than the small size significantly(P<0.05); with the density increasing ProPortion of breast was significantly decreased (P<0.05), ProPortion of breast of large size was higher than the small size significantly(P<0.05);ProPortion of thigh of large size was lowerer significantly than the small size (P<0.05).with the density increasing,driP loss rate of breast was significantly decreased(P<0.05);PH1 of thigh of large size was higher significantly than the small size (P<0.05);PH24 of thigh of large size was lower than the small size significantly(P<0.05);PH24 of thigh of high density was lower than the modest density and low density.Frequency of movement and wing stretching of large size were higher than small size significantly(P<0.05), Percentage of movement of large size were higher than small size significantly(P<0.05),Percentage of movement of large size were lower than small size significantly(P<0.05),with the density increasing,frequency of dust bathing was significantly decreased (P<0.05),Percentage of wing stretching of modest density was higher than high density and low density.Percentage of rest of modest density was lower than high density and low density. The degree of head feathers comPlete of large size was significantly higher than small size (P<0.05),stocking density had no significant effect on the degree of feathers(P>0.05). Stocking density and cage size can not significantly affect GSH-Px、SOD、MDA of 21 days;Along with the breeding density increasing,T-AOC of 21 days was decreased significantly as the density was increasing;Stocking density and activity sPace can not significantly affect T-AOC、GSH-Px、SOD、MDA of 42 days. FFA of large size of 21 days was significantly higher than small size (P<0.05);with the density increasing,ATCH of 21 dayswas significantly increased (P<0.05);FFA of large size of 42 days was significantly lower than small size (P<0.05);with the density increasing,Glu of 21 days was significantly increased (P<0.05);IL-1β of large size of 21 days was significantly lower than small size (P<0.05);with the density increasing,IL-1β of 21 days was significantly decreased(P<0.05);IL-6 of modest density of 21 days was lower than high density and low density significantly (P<0.05);IL-1β of modest density of 42 days was lower than high density and low density significantly (P<0.05);2.Battery rearing:ADFI、ADG、F/G、ABW、survival rateof high density was lower than the modest density and low density significantly(P<0.05),ADFI、ADG、F/G、ABW、survival rate of modest density was lower than high density and low density significantly(P<0.05).with the density increasing,ProPortion of thigh was significantly increased(P<0.05), high density can significantly decrease PH24 of breast(P<0.05),PHlof thigh of large size was higher than the small size significantly(P<0.05);PH1 and PH24 of modest density higher significantly than high density and low density(P<0.05).with the density increasing,frequency of Preening significantly decreased(P<0.05),Percentage of resting significantly increased(P<0.05).Percentage of feeding and movement of low density were higher than high density and low density significantly(P<0.05)The degree of neck feathers comPlete of high density was significantly higher than modest density and low density(P<0.05). Cage size and stocking density have no significant affect on The degree of head、back、anus and tail feathers.GSH-Px of large size was higher than the small size significantly(P<0.05),with the density increasing,GSH-Px was significantly decreased(P<0.05);MDA of modest density was significantly lower than high density and low density(P<0.05).SOD of large size was higher than the small size significantly(P<0.01),FA of thigh lenghth of large size was lower than the small size significantly(P<0.05).ACTH and IL-6 of large size was lower than the small size significantly(P<0.01).3.ComParison results of net rearing and battery rearing:ADFI、ADG、F/G、ABW of net rearing was higher than battery rearing significantly(P<0.05),but survival rate was lower than battery rearing significantly(P<0.05);ProPortion of thigh of net rearing was highrer than the battery rearing significantly(P<0.05),PH1 and PH24 of thigh of low density was higher significantly than high density (P<0.05).Frequency of movement、standing、Preening, dust bathing and wing stretching of net rearing were higher than battery rearing significantly(P<0.05),Percentage of feeding, drinking, dust bathing and wing stretching of net rearing were higher than battery rearing significantly(P<0.05),The degree of head feathers and neck feathers of net rearing was significantly higher than battery rearing (P<0.05),T-AOC and GSH-Px of net rearing was significantly higher than battery rearing (P<0.05),T-AOC of low density was higher than high density significantly (P<0.05).There was no significant difference in immunological stress indicators (P>0.05).ComPrehensive consideration,the bettery way to raise broilers under net rearing was large size modest density(2.88m~2,10/m~2),the bettery way to raise broilers under battery rearing was large size modest density(0.7m~2,14/m~2).ComParing net rearing and battery rearing,we can Come to the conclusion that 10/m~2under net rearing had better benefits.