| Brooding work directly affects the growth and development of chicks,and effect on production performance in laying period.Now,many factors had been studied,which can influence the effect of the brood,but the brood cage has rarely been studied.This experimental study of different sizes brood cages on growth,early production performance and immune effect of laying hens,and provide a reference for breeding.Experiment 1: The weight close to 1-day-old Roman Brown Commercial Layer 519 were included in present study.Randomly divided into 3 groups,were placed in large,medium and small cages,and were numbered group A,group B and group C.When put chicks into the cage wearing No.on wing.During the test,by adding non experimental chickens to ensure that rearing density of each group is same.This trial lasted for 8 weeks.This part determination growth performance,serum biochemical indices and bone strength of chicks.Experiment 2: At 118 days of age,From the A,B,C groups each randomly took healthy and well-developed chicken 90.Reared in the same house with 3 layers ladder cage,and each group with 3 replicates and 30 layers in one replicate.This trial lasted for 60 days.The results are as follows:1.The growth performance results show that,the average body weight,shank length and shank girth of group A were significantly higher than that of group C(P<0.05).The average body weight in A group and B group,at the age of 14 days was not significant difference(P>0.05),at the age of 14 days later that in group A was significantly higher than that in B group(P<0.05);at the age of 14 and 28 days that in B group was higher than that in C group(P<0.05),and at the age of 28 days later was not significant difference(P>0.05).The trend of daily gain was similar to weight,Only in 3~4 weeks of age,the daily intake in A group and C group was significant difference(P<0.05).The trend of shank length and shank girth were also similar to weight,but at the age of 4 and 8 weeks,there was no significant effect on tibia strength of different groups(P>0.05).At the age of 56 days,the weight in group A was close to the standard weight of Roman Brown Commercial Layer,but this index in group B and group C were lighter than the standard weight.2.The serum biochemical indicators show that,at the age of 28 days,The FT4-I in group A was significantly lower than that in group C(P<0.05).TP,GLB and T-CH in group A were significantly higher than that in group C(P<0.05).At the age of 56 days,FT3-I,FT4-I and T3/T4 were significantly different between group A and group C(P<0.05).The activity of ALP was significantly different between group B and group C(P<0.05).P and TG in group A were significantly lower than that in group C(P<0.05).There was no significant effect on other serum biochemical indicators among 3 groups(P>0.05).3.The performance of laying hens showed that,rearing with large cage and medium cage,age at first egg and 50% laying start age were in advance.The laying performance indexes are not significantly different among 3 groups(P>0.05).During the test,the mortality elimination rate only in group C was 1.11%.Only the egg yolk color of egg quality index between group B and group C reached significant level(P<0.05).4.The antibody titer results show that,the 1st and 4th result of H5 antibody titer had no significant difference between group A and group C(P>0.05),other time were group A significantly higher than group C(P<0.05).ND antibody titer results had no significant difference among 3 groups(P>0.05).In conclusion:Using large cage brood bred is more conducive to chick's growth,can improve early(118~176d)production performance and immune effect of H5. |
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