Effect of grazing and house-feeding on growth, slaughter performance and meat quality of mutton sheep.

The experiment was to study the effect of grazing and house-feeding on growth, slaughter performance and meat quality of mutton sheep. A total of 24 healthy and disease-free Duhan hybrid mutton sheep with a body weight (20.0±2.2) kg were randomly divided into grazing group and house-feeding group, with 12 replicates per group and one sheep per replicate, half in male and half in female. The sheep in the grazing group were fed a diet primarily composed of cypress seeds and cypress leaves, with the appropriate amount of basic diet. The sheep in the house-feeding group were fed a 30% cypress seeds in the basic diet. The pre-feeding period was 15 days and the formal period was 90 days. The results showed that the final weight and average daily gain of the mutton sheep in the house-feeding group were extremely higher than those in the grazing group (P<0.01), and the total weight gain was significantly higher than that in the grazing group (P<0.05). The live weight before slaughter, carcass weight, net meat percentage and dressing percentage of mutton sheep in the house-feeding group were significantly or extremely higher than those in the grazing group ( P<0.05 or P<0.01). The water loss rate and cooking loss rate of mutton in the house-feeding group were significantly higher than those in the grazing group ( P<0.05), and the pH24 h value of mutton in the grazing group was significantly higher than that in the house-feeding group (P<0.05). The content of aspartic acid, glutamic acid, leucine, phenylalanine, histidine, threonine and serine in the grazing group was significantly higher than those in the house-feeding group ( P<0.05). The content of alanine, valine and lysine in mutton sheep in the house-feeding group was significantly higher than those in the grazing group ( P<0.05), and the content of glycine was extremely higher than that in the grazing group ( P<0.01). The color, aroma, taste and total score of mutton in the grazing group were significantly higher than those in the house-feeding group ( P<0.05). The study indicates the house-feeding mode can improve the fatten and weight gain effect of mutton sheep, and improve the slaughtering performance of mutton sheep. The grazing feeding mode can improve the flavor and quality of mutton to a certain extent. [ABSTRACT FROM AUTHOR]