| In order to compare the effects of two different modes of yard-feeding and grazing on meat quality and serum fat and protein metabolism related indexes of Arbas cashmere goats,In the experiment,60 Arbas cashmere goats with half male and half female in similar weights and good health conditions were selected,and they were divided into yard-feeding and grazing groups,each with 30 animals.The experiment lasted for one year.The yardfeeding group was fed regularly and quantitatively with forage;the grazing group was grazing according to the conventional fixed method.At the end of each month,blood was collected from the jugular vein and the serum was separated.At the end of the test period,6 animals were randomly selected from the yard-feeding group and the grazing group,each with half male and female,and slaughtered in accordance with the ethnic minority slaughter method.Take the right limb quadriceps,longissimus dorsi,arm triceps,biceps femoris and other meat samples and save them for later use.Tenderness meter,gas chromatograph,automatic amino acid analyzer,biochemical analyzer,etc.were used to detect muscle physical and chemical properties,histological properties,and changes in serum fat and protein metabolism related indicators.The results are as follows:(1)Yard-feeding and grazing patterns can affect the slaughter performance and conventional ingredients of Arbas cashmere goats.The cooked meat rate and crude fat content of the yard-feeding group were higher than those of the grazing group,and the water loss rate,moisture content,and crude protein content were lower than those of the grazing group,but there was no significant effect(P> 0.05);the shear force of the grazing group was significantly higher than that of the yard-feeding group(P<0.05).(2)Yard-feeding and grazing patterns can have an impact on the fatty acid and amino acid composition of Arbas cashmere goats.The proportion of saturated fatty acids in the yard-feeding group was higher than that of the grazing group.The proportions of monounsaturated fatty acids,polyunsaturated fatty acids,n-3PUFA,and n-6PUFA were all lower than those of the grazing group,and the proportion of n-3PUFA was significantly lower than that of the grazing group.(P<0.05).The γ-linolenic acid grazing group was significantly higher than the yard-feeding group(P<0.01),and the arachidonic acid and eicosapentaenoic acid were significantly higher than the yard-feeding group(P<0.05).The contents of total amino acids,essential amino acids,non-essential amino acids,and total umami amino acids in the grazing group were higher than those in the yard-feeding group,and the difference was not significant(P>0.05).(3)The mode of yard-feeding and grazing can affect the muscle histological properties of Arbas cashmere goats.Compared with the yard-feeding group,the grazing group had smaller muscle fiber diameter and single muscle fiber cross-sectional area,but the difference was not significant(P>0.05).(4)The mode of yard-feeding and grazing can affect the related indexes of serum fat and protein metabolism of Arbas cashmere goats.The TG content of the yard-feeding was always higher than that of the grazing group,and it was extremely significantly higher than that of the grazing group in May(P<0.01);the changes of serum TC and HDL-C content were similar,and the grazing group was higher than the yard-feeding in January,February and March,The grazing group in April,May,and June was lower than the yard-feeding group.There was a very significant difference in serum TC content in March(P<0.01),a significant difference in serum HDL-C content in February and May(P<0.05),and a very significant difference in March and June(P<0.01);The LDL-C content was not significantly different(P>0.05);the serum TP,ALB,UREA content of the grazing group was always higher than that of the yard-feeding group.The results show that the innate grazing conditions make the Arbas cashmere goats have unique meat characteristics.Its meat protein content is high,the fat content is low,and the nutrient composition such as fatty acid,amino acid is balanced,and the human body is rich in essential components.However,it is undeniable that supplementary feeding of grazing cashmere goats in the dry and cold winter is beneficial to improve the metabolic state of the body and increase the tenderness of the meat. |
