Effects Of Housing System On Carcass Traits And Egg (Meat) Quality Of Taihang Chicken,Bashang Long-tailed And Rhode Island Red Hybrid Chicken

According to the current status of the laying hen in China,with reference to the housing system of foreign countris,combined with the living environment,health welfare and production performance of poultry,the study adopts Bashang long-tailed and Rhode Island Red hybrid chicken and Taihang chicken as experiment animals.The differences of egg quality,carcass traits and meat quality under two housing systems(conventional cage and flattening on floor)and different ages were studied to assess the effects of housing system,age and variety on the quality of chicken products.In this study,180 Bashang long-tailed and Rhode Island Red hybrid chicken and 180Taihang chicken at 22wk were selected as experiment animals,randomly divided into 2groups,including conventional cage(using 3 layers of upper and lower stacking cages,5cages per layer,3 chicken per cage)and flattening on floor(10m×7m×5m,flattening on concrete floor,0.389m~2per chicken),a total of 4 groups.The test period ranged from 22wk to 50wk.We collected 30 eggs in each group at 32wk,41wk,and 49wk for egg quality analysis,and 9 chicken randomly selected in each group for carcass traits and meat quality.Using a general linear model(including main effects and interaction)and bonferroni t test to perform multiple comparative analysis,the results are as follows:There was an interaction of housing system and age on egg weight and shell weight of Bashang long-tailed and Rhode Island Red hybrid chicken(P<0.05).The housing system,age and interaction had no significant effect on shape index(P>0.05).The albumen height at 41wk was very significant higher than 49wk(P<0.01),significantly higher than 32wk(P<0.01);the yolk weight at 49wk was significantly higher than 41wk and 32wk(P<0.01),and at 41wk was significantly higher than 32wk(P<0.01).The Haugh Unit at41wk was significantly higher than 49wk(P<0.05);shell strength at 32wk and 41wk was very significantly higher than 49wk(P<0.01).The yolk color in caged group was very significantly higher than flattening on floor(P<0.01).There was an interaction of housing system and age on semi-eviscerated percentage,eviscerated percentage of Bashang long-tailed and Rhode Island Red hybrid chicken(P<0.05).The Carcass percentage in caged group was significantly higher than flattening on floor(P<0.05).The semi-eviscerated weight,eviscerated weight,breast meat weight and breast meat percentage in caged group were significantly higher than flattening on floor(P<0.05).The alive weight at 41wk and 49wk was very significantly higher than32wk(P<0.01);Carcass weight at 49wk was very significantly higher than 32wk(P<0.01),and at 41wk was significantly higher than 32wk(P<0.05);breast meat weight at 49wk was very significantly higher than 41wk(P<0.01),significantly higher than 32wk(P<0.05);breast meat percentage was significantly higher at 49wk than 32wk and 41wk(P<0.05);thigh meat weight at 49wk was very significantly higher than 32wk and 41wk(P<0.01),and at 41wk was very significantly higher than 32wk(P<0.01).Breast meat percentage at49wk and 32wk was very significantly higher than 41wk(P<0.01).There was an interaction of housing system and age on moisture loss rate and breast meat color(lightness,yellowness)of Bashang long-tailed and Rhode Island Red hybrid chicken(P<0.05).The housing system,age and interaction had no significant effect on redness and pH value(P>0.05).The shearing force of breast meat in caged group was significantly higher than flattening on floor(P<0.05).The shearing force of breast meat at32wk was very significantly higher than 41wk(P<0.01).There was an interaction of housing system and age on moisture loss rate,thigh meat color(lightness,redness)and pH value of thigh meat of Bashang long-tailed and Rhode Island Red hybrid chicken(P<0.05).The housing system,age and interaction had no significant effect on yellowness of thigh meat(P>0.05).The shearing force of thigh meat in caged group was significantly higher than flattening on floor(P<0.05).The shearing force of thigh meat at 32wk was very significantly higher than 49wk(P<0.01).There was an interaction of housing system and age on egg weight,albumen height,Haugh Unit,shell strength and yolk color of Taihang chicken(P<0.05).The housing system,age and interaction had no significant effect on shape index(P<0.05).The shell weight at 41wk was very significantly higher than 32wk(P<0.01),significantly higher than49w(P<0.05).The yolk weight at 49wk was very significantly higher than 41wk and 32wk(P<0.01),and at 41wk was very significantly higher than 32wk(P<0.01).The albumen height flattening on floor was very significantly higher than caged group(P<0.01),and the yolk weight was significantly lower than caged group(P<0.05).The housing system,age and interaction had no significant effect on Carcass percentage of Taihang chicken(P>0.05).The semi-eviscerated percentage,eviscerated percentage and breast meat percentage flattening on floor were significantly higher than caged group(P<0.05).The alive weight,Carcass weight and eviscerated weight at 49wk was very significantly higher than 32wk and 41wk(P<0.01);the breast meat weight at49wk was significantly higher than 32wk and 41wk(P<0.05);the semi-eviscerated weight at 49wk was very significantly higher than 32wk(P<0.01).The semi-eviscerated percentage at 49wk was significantly higher than 32wk(P<0.05).The eviscerated percentage at 41wk was very significantly higher than 32wk(P<0.01),and at 49wk was significantly higher than 32wk(P<0.05);the thigh meat weight at 49wk was significantly higher than 41wk(P<0.01),and at 32wk was significantly higher than 41wk(P<0.05);the thigh meat percentage at 32wk was very significantly higher than 41wk(P<0.01),and at49wk was significantly higher than 41wk(P<0.05).The housing system,age and interaction had no significant effect on the pH value of breast meat of Taihang chicken(P>0.05).The lightness in caged group was significantly higher than flattening on floor(P<0.05).The moisture loss rate at 41wk was very significantly higher than 32wk and 49wk(P<0.01),and at 32wk was significantly higher than 49wk(P<0.05);yellowness at 49wk was very significantly higher than 32wk(P<0.01);redness at 32wk was very significantly higher than 49wk(P<0.01);the shearing force in 32w was very significantly higher than 41w(P<0.01).There was an interaction of housing system and age on moisture loss rate of thigh meat of Taihang chicken(P<0.05).The housing system,age and interaction had no significant effect on yellowness,shearing force and pH value of thigh meat(P>0.05).The lightness of thigh meat color flattening on floor was significantly higher than caged group(P<0.05).The lightness of thigh meat color at 32wk was very significantly higher than 49wk(P<0.01);the redness at 49wk was very significantly higher than 32wk(P<0.01).The above results indicate that housing system and age had an interaction on egg weight,shell weight,shell strength,eviscerated percentage,thigh meat percentage,moisture loss rate andyellowness of breast meat,moisture loss rate and meat color(lightness,redness)and pH value of thigh meat.Variety had a significant effect on egg weight、albumen height、shell weight、Haugh Unit、shape index、shell strength、yolk color、alive weight、carcass weight、semi-esvisccerated weight、esvisccerated weight、thigh meat weight、breast meat weight、breast meat percentage、moisture loss rate of breast meat、pH value of thigh meat and yellowness of thigh meat.