Effects Of Cage Position,Stocking Density And Mid-to-late Term Restriction Of Feed Intake On Production Performance Of Broilers

The purpose of this study was to investigate the effects of cage position,stocking density,and mid-to-late term restriction of feed intake on the production performance of broilers.The results of this study could be useful for the guidance of the management of broilers.The automatic poultry house and the ordinary poultry house were selected as chicken house samples,and the temperature,humidity,ammonia concentration and wind speed in the front,middle and rear areas of the chicken house were measured,and the water environment parameters of the two types of poultry houses were analyzed.The results show that: from the front to the rear of the automatic and ordinary poultry houses: the temperature tends to increase,the humidity tends to decrease,the wind speed changes between different cage layers are larger,the higher the cage layer,the ammonia concentration tends to decrease,and the different cage layers The range of wind speed varies greatly.In the automated poultry house,432 14-day-old R0SS308 broilers with similar body weight were selected and average assigned to 36 cages at the front,middle,and later of the house.The body weight was determined at the 21 and 40 days of age.In ordinary broilers house,288 24-day-old 817 broilers with similar body weight were selected and average assigned to 24 cages at the front,middle,and later area of the house.The body weight was determined at the 24 and 48 days of age.The results showed that the average daily weight gain of broilers in the first layer of stack cage was significantly higher than that in the other three layers in the automated house(P<0.05).The body weight of broilers in the front area was significantly higher than that in the middle and rear areas at 40-days of age in the automated house(P<0.05).In the ordinary housing system,the body weight of 817 broilers raised in the front area was significantly higher than that in the later area at 48 days of age(P<0.05).The body weight of 817 broilers raised in the second layer was significantly higher than that in the first layer at 48 days of age(P<0.05).300 14-day-old ROSS308 broilers with similar body weight were assigned to 6 groups with different stocking density(from 10 to15 birds per cage),each group content 5 replicates.All ROSS308 broilers were housed in the automated system and the area for each cage was 0.64m2.Body weights were recorded individually at 40 days of age.In the ordinary broilers house(0.49m2 of bottom area per cage),360 25-day-old 817 broilers with similar body weight were assigned to 4groups,and the density was set to 11 birds /cage to13 birds /cage,with 10 replicates in each group.Body weights were recorded individually at 48 days of age.The results showed that the body weight of 41-day-old ROSS308 broilers decreased with the increase of stocking density.However,there was no significant difference in body weight and feed meat ratio of 49-day-old 817 broilers among 4 groups.To study the effects of mid-to-late term restriction of feed intake on the growth,slaughter performance,meat quality,and the intestinal absorption capacity of broilers,two experiments were conducted.Experiment 1,180 24-day-old 817 broilers with similar body weight were divided into three groups: 5% restriction of feed intake group,control group,and 5% increase of feed intake group.There were 5 replicates in each group.At the 48 days of age 15 birds from each group were selected for use in subsequent experiments.Experiment 2,total of 240 27-day-old 817 broilers were selected and were divided into two groups:5% restriction of intake and control group,with 10 replicates in each group.At the 48 days of age 20 birds from each group were selected for slaughter performance,and meat quality analysis.The results showed that the restriction feed intake of the 817 broilers during 24-47 days could reduce the feed conversion ratio and the fecal nitrogen content by 0.1 and 6.74%,respectively.The 5% restricted diet group presented the highest of the small intestine absorption capacity(V/C).However,the middle and later periods feeding restriction have no significant effects on carcass composition and meat quality of 817 broilersTaken together,the environmental conditions of the automated housing system was better than the ordinary housing system.Cage positions and stocking density may have certain effects on the production performance of the 817 broilers.Appropriate feeding restriction in the middle and later periods of 817 broilers is helpful to improve feed utilization rate.