Effects of melatonin implantation on carcass characteristics, meat quality and tissue levels of melatonin and prolactin in Inner Mongolian cashmere goats.

BACKGROUND

Implantation of goats with melatonin can induce cashmere growth and significantly increase cashmere production performance. However, the impact of melatonin implantation on the carcass characteristics, meat quality and related hormone levels in muscle and viscera of cashmere goats has not been studied. This experiment was conducted to determine the effects of melatonin implantation of cashmere goats during the non-growing period on meat quality and related hormone levels in the tissues. It aimed to provide a theoretical basis for the practical application of melatonin in cashmere goat production systems.

RESULTS

Melatonin implantation (2 mg/kg live weight) had no influence ( > 0.05) on daily weight gain, carcass weight, dressing percentage, loin muscle area, or the pH, moisture level, crude fat (except for muscle) and amino acid content of muscles of cashmere goats. After implantation for 1 month, shear force of and water loss rate of and of cashmere goats were increased ( < 0.05), whereas the cooking yield of muscle was reduced ( < 0.05). The melatonin treatment decreased ( < 0.05) muscle crude protein, muscle crude fat and ∑-3PUFA content and decreased ( < 0.05) ∑-6PUFA content. However, after 2 months of implantation most of these effects had resolved. Melatonin implantation had no effect ( > 0.05) on the melatonin or prolactin contents of kidney, heart, spleen, liver, , and muscles. Melatonin content of lung tissue was lowered ( < 0.05) and that of prolactin was elevated ( < 0.05) by the melatonin implantation.

CONCLUSION

This study has shown little impact of melatonin implantation of cashmere goats on carcass quality. A few meat quality indices i.e., shear force, water loss rate, ∑-3PUFA, ∑-6PUFA, and crude protein content of ; water loss rate, cooking yield and crude protein content of ; ether extract, crude protein content of ; were affected briefly (at 1 month of implantation) but these effects were not evident after 2 months of implantation. There was little effect of the melatonin treatments on tissue levels of melatonin or prolactin except in lung.