Abstract:

This experiment was to study the effects of adding different ratios of fermented Hypsizygus marmoreus mushroom residue to a standard feed， on the slaughter performance， and meat amino acid and fatty acid content of Jianyang big ear goats. A single factor experiment design was chosen， and 48 Jianyang big ear goats were selected and randomly divided into 4 groups with 12 goats in each group. The treatments comprised addition of zero （group C， control group）； 20% （group L）， 30% （group M）， and 40% （group H） fermented H. marmoreus mushroom residue to the basic diet. The pre-test diet adaptation period was 10 days， and the trial period was 120 days. It was found that： 1） The pre-slaughter live weight and the eye muscle areas of group L were significantly higher than in group H （P<0.05）； While the weights of lung， kidney， rumen， small intestine， large intestine， and the ratio of the rumen weight to the pre-slaughter live weight were significantly higher than in the other three groups （P<0.05）. The eye muscle area and the weights of lungs， kidneys， rumen， small intestine and large intestine showed secondary changes proportional to the added amount of fermented mushroom residue （P<0.05）. 2） There was no significant difference in the meat pH among the groups （P>0.05）. The 24 and 48 h drip loss of group L was significantly lower than other groups （P<0.05）， and there were secondary changes proportional to the level of addition of mushroom residue in that the yield of cooked meat rate was significantly higher than in group H （P<0.05） while the shear force was significantly lower than in group H （P<0.05）. 3） The total amount of essential amino acids in the longissimus dorsi muscle in group L was significantly higher than in group C （P<0.05）， and the contents of aspartic acid， threonine， leucine， lysine， and arginine were significantly higher than in groups C and H （P<0.05）. The contents of alanine， valine and isoleucine in group L were significantly higher than other groups （P<0.05）， and the contents of proline and glycine were significantly higher than in groups C and M （P<0.05）. Among four groups， the contents of valine， isoleucine， lysine and aspartic acid showed secondary changes proportional to the level of mushroom residue addition （P<0.05）. 4） There were no significant differences in fatty acid content among the groups （P>0.05）. Along the addition gradient， the contents of C18：0 and C18：3n3 fatty acids showed either quadratic change or linear increase in proportion to the level of addition （P<0.05）. The content of C18：3n3 in group H was increased by 16.48% compared with group C. The contents of polyunsaturated fatty acids （PUFA） and n-3 PUFA in the test groups increased to some extent， compared with group C. The n-6/n-3 decreased by 0.64%， 11.73% and 12.34%， respectively for groups L， M and H， compared with group C. To sum up， supplementation of a standard diet with 20% fermented H. marmoreus mushroom residue improved internal organ development and meat quality of goats.

Key words: Hypsizygus marmoreus mushroom residue, slaughter performance, meat quality, amino acid, fatty acid