Effects Of Environmental Temperature And Humidity On Healthy Production Of Pullets And Layers

This topic is aimed at pullets'heat effect is not clear,layers'cold effect is unknown.On the one hand,study the different temperature on the impact of the development of pullets'sexual maturity and body maturity to establish suitable for raising temperature and limit.On the other hand,it studies the effect of different temperature and humidity conditions on production performance and health of laying hens,and establishes a suitable cold environment for healthy production.In the experiment of the effects of different temperature on the sexual maturity and mature development of pullets.Select similar weight of 11 weeks age pullets,360 were randomly divided into 5 groups,each group of 6 repeat,each repeated 12,reared in the same structure of 5 rooms but without feeling the temperature of each other.Test batch processing temperature,the temperature-control room temperature daily 10:00-18:00 respectively set at22,24,26,28 and 30°C the rest of the time constant of 22°C.The trial period is 8 weeks.The results showed that the body surface temperature of the pullets was basically the same as that of the treatment temperature.Different temperature of dealing with the pullets'body core temperature in the processing phase of the day?10:00-18:00?basic is higher than the processing phase,and at the beginning of time?10:00?has a tendency to surge,and after the treatment?18:00?has a tendency to drop.The weight of the chicken was higher than that of other treatment temperatures,especially after 6-8 weeks,indicating that 24°C was more beneficial to the growth of pullets.After 7-8 weeks of different temperature treatment,the intake of chicken in 24°C was higher than that of other treatment temperature,and the intake of chicken in 30°C was relatively low.The concentrations of E₂ in the serum after 4 weeks'treatment in the 24°C group were the lowest.After 8 weeks of different temperature treatment,the oviduct length of chicken in 22°C was significantly higher than that in other groups.After4 weeks'treatment of T3 concentrations at different temperatures was the highest concentration in the 24°C.The body ruler of 24°C was the best.After 4 weeks'treatment,the mRNA expression levels of the IGF-1R in the hypothalamus of 26 and 28°C were significantly lower than that of 22°C.The m RNA expression level of ADPNR in the hypothalamus of 26,28 and 30°C were lower than that of 22°C.After 8 weeks'treatment,the mRNA expression level of ADPN in abdominal fat of 30°C was higher than that of 24°C,but the mRNA expression level of ADPNR in the hypothalamus of 26°C was significantly lower than that of 28°C.In the experiment of the effects of different temperature and humidity conditions on production performance and health of laying hens in winter.From November 30,2017 to February 5,2018,a total of 192 layers with a similar weight and egg production rate were selected,and they were randomly divided into four groups.Each group had 6 repeats,each of which was repeated with 8 chickens.They are housed in four identical but mutually exclusive rooms.Each room is equipped with different heating and humidification systems to create four different environments:dry-warm,wet-cold,dry-cold,wet-warm.The trial period is 9 weeks.Theresultsshowedthattheresultsofdrinkingwater:dry-warm>wet-cold>dry-cold>wet-warm.In the 9th week,the egg rate of the dry-cold group and wet-warm group was higher than that of dry-warm group.The intake of the dry cold group was higher than that of the other groups.The average egg weight of dry-cold group was significantly higher than that of wet-warm group.The egg production in the dry-cold group was higher than that in the dry-warm group.After nine weeks,the yolk of the wet-cold group was higher than that of the dry-cold group.In the second week,the surface temperature of dry-warm and the wet-warm group were higher than the dry-cold group and the wet-cold group.The mRNA expression of TNF-?in lung tissues of dry-warm group was higher than that of wet-warm group.The dry-warm group of IL-6 mRNA expression was higher than that of the wet-cold group.The mRNA expression of MUC5AC showed that the dry-warm group was higher than the wet-warm group.The mRNA expression of TNF-?in the uterine tissues of dry-warm was higher than that in the wet-warm group and sIgA in wet-cold group was higher than that of the other groups.Above studies show that young chickens in 22 to 28°C environment can adjust itself,more advantageous 24°C,30°C adverse to growth and development.The wet-warm and dry-cold environment in winter is the most favorable to the healthy production of laying hens,and the dry-warm environment is the most unfavorable.