Effects Of Temperature And Stocking Density On Growth,Serum Biochemical Indexes And Environmental Quality Of Sheep

In this study,the effects of temperature and stocking density on sheep growth performance,serum biochemical indicators and sheep environment were studied to provide a basis for healthy green sheep production and sustainable development.The test adopts 2×3 two-factor factorial design.The factor A is temperature,which is divided into low temperature(5~10°C)and high temperature(25~30°C).The factor B is stocking density and divided into low density(1.32 ?/body),medium density(0.825 ?/body)and high density(0.6 ?/ body)were tested in an artificial climate chamber.The result is as follows:The effects of temperature and stocking density on the daily gain of sheep were not significant(P>0.05),but they decreased with temperature and stocking density.The weight gain of rams was the highest at low temperature and low density,and the lowest was high temperature and high density.For 0.24 and 0.09 kg/d · only-1,the weight gain of the ewes in the ewes was highest in the low-temperature medium density group,and lowest in the hightemperature high-density group,which was 0.14 and 0.03 kg/d · only-1,respectively.The effects of temperature on serum corticosterone creatine kinase in ram were not significant(P>0.05),and there was significant difference in serum IgG and lactate dehydrogenase(P<0.05).There was no significant difference in serum corticosterone levels in ewes(P>0.05),serum IgG,creatine kinase,and lactate dehydrogenase had significant differences(P<0.05).The interaction of breeding density and temperature had a significant effect on serum IgG,creatine kinase,and lactate dehydrogenase in ewes(P<0.05),sheep creatine kinase and lactate dehydrogenase decreased with the increase of the raising density,and increased with the increase of temperature.Ram serum IgG increased with temperature and raising density,ewe Serum IgG decreased with increasing temperature.The ammonia concentration and hydrogen sulfide concentration in the sheep house increased with increasing temperature and stocking density.The concentrations of carbon dioxide and methane decreased with increasing temperature,and increased with increasing stocking density.Regardless of the high temperature or low temperature environment,the number of indoor air bacteria in the high density group was higher than that in the low density group and medium density group,and the total number of air bacteria and mold in the livestock house increased with the increase of temperature and stocking density.There are more bacteria,Staphylococcus aureus,Escherichia coli,and molds,and there are fewer Salmonella.In summary,the environment of the livestock house is the worst under high temperature and high density,and the ammonia concentration,hydrogen sulfide concentration,humidity,and airborne bacteria in the livestock house are all the highest.The feed intake and weight gain are also the lowest.It is beneficial to reduce the breeding density and temperature.Maintain a good barn environment and sheep growth.The sheep growth performance,serum biochemical indexes and environmental quality indicators of the livestock house were comprehensively studied.Under the conditions of this experiment,the stocking density of 0.82 ?/head was most conducive to sheep growth and health.