Abstract:
In order to investigate the effects of adding sodium butyrate to high-lipid diet on growth, digestive enzymes activity, immunity, and antioxidant capacity of juvenile
Carassius auratus gibelio, this experiment selected 450healthy juvenile
C. auratus gibelio with an initial body weight of (20.41±0.44) g as the research subjects. The high-lipid diet (crude lipid content of 7.31%) with different sodium butyrate supplemental levels 0 (SB0), 0.1% (SB0.1), 0.3% (SB0.3), 0.6% (SB0.6), and 1.2% (SB1.2) were fed to
C. auratus gibelio for 8 weeks. The results showed that: (1) In terms of growth, the weight gain rate (WGR) and specific growth rate (SGR) of the SB0.3 and SB0.6 groups were significantly higher than those of the other groups (
P<0.05), with SB0.3 group showing the highest values (120.63% and 1.41%/d, respectively). The feed conversion ratio (FCR) decreased first and then increased with sodium butyrate addition (
P<0.05), reaching a minimum of 1.60 at 0.3% supplementation. The addition of sodium butyrate to high-lipid diet significantly increased the protein deposition rate (
P<0.05); (2) Compared with the control group, intestinal lipase and amylase activities in SB0.1, SB0.3, SB0.6, and SB1.2 groups were significantly increased (
P<0.05), while protease activity was significantly higher in the SB0.3 group (
P<0.05), and there was no significant difference between the control group and the other sodium butyrate addition groups. (
P>0.05); (3) In terms of immunity and antioxidant status, serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities exhibited a trend of first decreasing then increasing with the increase of sodium butyrate supplemental level (
P<0.05); The hepatopancreas antioxidant enzyme activity increased first and then decreased (
P<0.05), while malondialdehyde (MDA) content showed the opposite trend (
P<0.05). This experiment confirms that adding an appropriate amount of sodium butyrate to high-lipid diet can significantly improve the digestive capacity, enhance immunity and antioxidant functions, and promote growth in juvenile
C. auratus gibelio. Quadratic regression analysis of growth performance combined with the activity of digestive enzymes, immunity and antioxidant capacity, suggests an optimal sodium butyrate dosage range of 0.3%—0.67%.