Abstract:
This study evaluated the effects of dietary copper sulfate (CuSO
4), glycine chelated copper (Cu-Gly), copper hydroxymethionine (Cu-MHA) on growth, antioxidant enzymes and intestinal morphology of juvenile pearl gentian grouper (
Epinephelus lanceolatus ♂ ×
Epinephelus fuscoguttatus ♀). Juvenile pearl gentian grouper with the average body weight of (9.00±0.00) g were randomly divided into 3 groups with 3 replicates in each group and 30 fish in each replicate to feed isonitrogenous and isolipidic experimental diets with 3 different copper sources for 8 weeks. (1) The weight gain ratio (
WGR), survival ratio (
SR) in Cu-Gly and Cu-HMA groups were significantly higher than those in CuSO
4 group (
P<0.05). (2) The hepatosomatic index (
HSI) and viscerosomatic index (
VSI) in Cu-HMA group was significantly higher than those in CuSO
4 and Cu-Gly groups (
P<0.05). There was no significant difference in condition factor (
CF) among all groups (
P>0.05). (3) Cu contents of vertebrae in Cu-Gly and Cu-HMA groups were significantly higher than that in CuSO
4 group (
P<0.05). (4) The serum concentrations of triglyceride (TG) and low-density lipoprotein cholesterot (LDLC) in CuSO
4 group was significantly higher than those in Cu-Gly and Cu-HMA groups (
P<0.05). The serum concentration of high-density lipoproteot cholesterin (HDLC) in CuSO
4 group was significantly lower than that in Cu-Gly and Cu-HMA groups (
P<0.05). (5) The activity of serum ceruloplasmin (CP) in CuSO
4 group was significantly higher than that in Cu-Gly and Cu-HMA groups (
P<0.05). (6) The plica height (PH) of midgut and hindgut in Cu-HMA group were significantly higher than those in CuSO
4 and Cu-Gly groups (
P<0.05). These results revealed that dietary adding Cu-Gly and Cu-HMA could improve intestinal morphology and serum lipid metabolism to ameliorate growth of juvenile pearl gentian grouper.