Study On Adaptability,Growth Performance And Meat Quality Of Dupo And Suffolk Sheep

In this study,the physiological and biochemical indexes of Dupo and Suffolk sheep with the same body condition,healthy and disease-free,the same month-old in Sano sheep farm of Siziwang Banner in Ulanchabu City of Inner Mongolia were tested under heat stress and cold stress,and compared with Mongolian sheep with strong local adaptability.The growth perfonnance,reproductive performance and immune performance of Dupo and Suffolk sheep were measured and recorded throughout the year.The physiological and biochemical indexes,production performance and meat quality characteristics of Dupo sheep and Suffolk sheep under cold and heat stress were studied in order to provide data reference for introduction,improvement and cross utilization of Dupo sheep and Suffolk sheep in other areas of Inner Mongolia.The results showed that when the ambient temperature increased byl ?,the body temperature of Dupo sheep increased by 0.08?,the respiratory rate increased by 10.79 times per minute and the heart rate increased by 5.96 times per minute;the body temperature of Suffolk sheep increased by 0.01?,the respiratory rate increased by 3.02 times per minute and the heart rate increased by 2.84 times per minute;the average body temperature of Mongolian sheep increased by 0.12?,the respiratory rate increased by 3.65 times per minute and the heart rate increased by 1.64 times per minute.Under heat stress,the body temperature of Suffolk sheep in the morning and afternoon was significantly higher than that of Dupo sheep and Mongolian sheep(P<0.05),but the temperature difference of Suffolk sheep in the afternoon and afternoon was significantly lower than that of Dupo sheep and Mongolian sheep(P<0.05).The effect of environmental temperature change on respiratory frequency and heart rate of Suffolk sheep was significantly lower than that of Mongolian sheep(P<0.05),and that of Mongolian sheep was significantly lower than that of Dupo sheep(P<0.05).There was no significant difference between frequency and heart rate(P>0.05);there was no significant difference in serum T3 and T4 contents between Dupo sheep,Suffolk sheep and Mongolian sheep(P>0.05);erythrocyte potassium contents in Dupo sheep and Mongolian sheep were significantly higher than those in Suffolk sheep(P<0.05);and there was no significant difference in serum IgA,IgM,IgG contents between Dupo sheep,Suffolk sheep and Mongolian sheep(P>0.05).Under cold stress,the temperature of Dupo sheep decreased by 0.039?,Suffolk sheep by 0.022?,Mongolian sheep by 0.015?,Dupo sheep by 0.229 times/min,Suffolk sheep by 0.323 times/min,Mongolian sheep by 0.014 times/min,Dupo sheep by 0.753 times/min,Suffolk sheep by 0.432 times/min,Suffolk sheep by 0.323 times/min,Mongolian sheep by 0.014 times/min,and Dupo sheep by 0.753 times/min.The heart rate of Mongolian sheep decreased 1.049 times per minute.Dupo sheep and Suffolk sheep had lower body temperature,lower respiratory rate,deeper breathing and slower heart rate;the body was damaged,the ability of protein metabolism was reduced,and the speed of fat metabolism was accelerated.The stress degree of Suffolk sheep was significantly lower than that of Dupo sheep and Mongolian sheep(P<0.05);the immune ability of Dupo sheep,Suffolk sheep and Mongolian sheep decreased,but cold stress had a greater impact on the immunity of Dupo sheep.Small.The body weight and growth rate between 3 months and 12 months were Suffolk ram,Dupo ram,Suffolk ewe and Dupo ewe according to breed and from high to low,respectively.The average daily gain of 3-month-old Dupo sheep and Suffolk sheep was significantly higher than that of 6-month-old and 12-month-old(P<0.05),and that of 6-month-old was significantly higher than that of 12-month-old(P<0.05).The estrus rate of adult ewes was 100%,lambing rate was more than 160%,reproductive survival rate was more than 92%,mortality rate was only 2%-3%.Dupo sheep and Suffolk sheep can maintain higher growth performance,reproductive performance and immune performance.The fat deposition and growth rate of Suffolk sheep were significantly higher than those of Dupo sheep and Mongolian sheep(P<0.05).There was no significant difference in meat color between Dupo sheep,Suffolk sheep and Mongolian sheep(P>0.05).Suffolk mutton is tender and its cooked meat rate is higher,but Dupo and Suffolk sheep are corrupt at 24 hours.Suffolk sheep had better slaughter performance,meat quality,routine composition,amino acid and fatty acid content than Dupo sheep.