Comparative study of slaughter performance and meat quality of Angus cattle and Xiangxi yellow cattle of different ages

【Objective】The purpose of this study was to compare the differences in slaughter performance and meat nutrient quality between Angus cattle and Xiangxi yellow cattle at different age stages. It provided scientific basis for enriching the breeding data of Xiangxi yellow cattle and Angus cattle, and carrying out the improvement of Xiangxi yellow cattle varieties and breeding of new varieties(lines). 【Method】30 pure-bred Xiangxi yellow cattle and 30 Angus cattle were selected with the same initial weight, fed in a single column under the same standard feeding conditions, and slaughtered in batches at the age of 6, 18 and 30 months. Slaughter performance, meat quality and nutritional value were determined.【Result】The results showed that with the increase of age, Angus cattle and Xiangxi yellow cattle slaughter performance increased gradually. At 30 months, Angus cattle slaughter rate could reach 49.98%, cooked at a rate of 67.56%, eye muscle area was 4333.49 mm², the shear force was 44.13 N, the Xiangxi yellow cattle slaughter rate was 48.98%, the cooked meat at a rate of 65.94%, eye muscle area was 4042.78 mm², shear force was 50.18 N. At the same age stage, Angus cattle and Xiangxi yellow cattle had no significant differences in slaughter rate, drip rate, water loss rate and contents of crude protein, copper(Cu), iron(Fe) and lead(Zn) (P>0.05, the same below), but there were significant differences in eye muscle area and shear force at each age stage(P<0.05, the same below). The total amino acid(TAA) content of Angus cattle was 18.61%-19.11%, the essential amino acid(EAA) content was 7.70%-7.95%, the total amino acid content of Xiangxi yellow cattle was 18.28%-19.43%, the essential amino acid content was 7.27%-7.82%, and the EAA/TAA of each cattle species was about 40.00% in all the monthly stages. The difference between the two cattle species in the same stage was not significant. However, difference between the two cattle at the same age was significant. Saturated fatty acid contentinAngus beef was 44.51%-49.58% monounsaturated fatty acid content was 31.93%-37.74%, content of polyunsaturated fatty acids was 13.03%-23.19%. Saturated fat content in Xiangxi yellow beef was 47.22%-49.70%, monounsaturated fatty acid content was 34.21%-39.53%, content of polyunsaturated fatty acids was 12.89%-19.33%. At the same age, saturated fatty acid content in Angus cattle was lower than that of Xiangxi cattle and the difference was significant, but unsaturated fatty acid content was higher than that of Xiangxi yellow cattle.【Conclusion】Through comparison, it is found that the slaughter rate and meat quality of Xiangxi yellow cattle and Angus cattle are basically the same, which is suitable for the production of high-quality and high-end beef. At the same time, it also provides scientific basis for the introduction of Angus cattle to improve the individual size and slaughter rate of Xiangxi yellow cattle.