Abstract:

Objective: To investigate the growth, muscle quality and gene expression of lipoprotein lipase (LPL) and fatty
acid synthase (FAS) of Schizothorax prenanti Tchang (SPT) at different growth stages. Methods: SPT with body weights of
(137.8 ± 1.7) g (small, juvenile), (312.4 ± 11.8) g (medium, subadult) and (500.9 ± 31.4) g (large, adult) were collected,
respectively. Their body condition indexes, visceral indexes and major muscle nutrients were determined. Meanwhile, LPL
and FAS mRNA levels in liver and muscle of SPT at the juvenile, subadult and adult growth periods were evaluated by realtime
PCR. Results: Compared with the small group, boby condition indexes, hepatopancreas index (HIS), mesenteric lipid
index and water content were reduced in the medium group and large group (P < 0.05). The contents of crude protein and
crude ash showed no significant change in muscle. The intermuscular fat was the least abundant in the large group (P < 0.05).
The LPL and FAS mRNA expression levels in liver for the small group, medium and large group were significantly higher
than in muscle (P < 0.05). The LPL mRNA and FAS mRNA expression levels in liver were the lowest in the large group
(P < 0.05). The LPL mRNA and FAS mRNA expression levels in muscle were the highest in the medium group (P < 0.05).
Conclusion: The essential nutrients in muscle are reduced at the adult stage, and the content of intramusclar fat is correlated
with the expression of LPL mRNA and FAS mRNA.

Key words: Schizothorax prenanti Tchang, growth, quality, lipoprotein lipase, fatty acid synthase