Abstract:Xinjiang brown cattle is the first domestically cultivated dairy and meat dual-purpose cattle breed in China,which is bred and improved by introducing the blood of American and Swiss brown cattle.In order to explore the application value and operational precautions of ultrasonic scanners in the breeding and improvement of Xinjiang brown cattle,this experiment used B-ultrasound to measure meat quality traits such as backfat thickness,eye muscle area,intermuscular fat,and waist muscle height in American New hybrid brown cattle cows at 18,24,and 36 month old,and 18 month old bulls,in order to provide data basis for the breeding and improvement of Xinjiang brown cattle and ultrasonic live measurement technology.The results showed that B-ultrasound could clearly and accurately measure the relevant meat quality traits.The eye muscle area of 36 month old adult Meixin hybrid brown cattle was significantly higher than that of 18 month old and 24 month old(P<0.05),and the intermuscular fat of 36 month old cattle was significantly higher than that of 18 month old cattle(P<0.05);The backfat thickness of 18 month old Meixin hybrid bulls was significantly higher than that of cows(P<0.05),and the waist muscle height and eye muscle area were significantly higher than those of cows(P<0.01).There was no significant difference in intramuscular fat content(P>0.05).The ultrasound in vivo measurement method can effectively reflect the meat quality indicators of beef cattle.As the age increases,the meat quality related indicators of Meixin hybrid brown cattle show an upward trend,and fat deposition accelerates in adulthood;Young Meixin hybrid bulls have much higher developmental performance than cows and have good selection and breeding value.
