Effects of dietary choline on liver lipid composition, liver histology and plasma biochemistry of juvenile yellowtail kingfish (Seriola lalandi)

Abstract

Choline plays a crucial role in lipid metabolism for fish, and its deficiency in aquafeed has been linked to compromised health and growth performance. A 56-d experiment was conducted to examine the effects of dietary choline on lipid composition, histology, and plasma biochemistry of yellowtail kingfish (Seriola lalandi; YTK; 156 g initial body weight). The dietary choline content ranged from 0.59 to 6.22 g/kg diet. Three grams of 2-amino-2-methyl-1-propanol (AMP)/kg was added to diets, except for a control diet, to limit de novo choline synthesis. The results showed that the liver lipid content of YTK was similar among diets containing AMP and dominated by free fatty acids (FFA). In contrast, fish fed the control diet had significantly elevated liver triacylglycerol (TAG). Generally, the saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), and polyunsaturated fatty acids (PUFA) content of liver lipid in fish fed diets containing AMP was not influenced by choline content. The SFA and MUFA of liver lipid in fish fed the control diet was similar to other diets except for a decrease in PUFA. The linear relationship between lipid digestibility and plasma cholesterol was significant, otherwise most parameters were unaffected. When AMP is present, higher dietary choline reduced the severity of some hepatic lesions. This study demonstrated that choline-deficiency affects some plasma and liver histology parameters in juvenile YTK which might be useful fish health indicators. Importantly, this study elucidated potential reasons for lower growth in choline-deficient YTK and increased the knowledge on choline metabolism in the fish.

Adequate levels of dietary sulphur amino acids impart improved liver and gut health in juvenile yellowtail kingfish (Seriola lalandi)

“…However, in the absence of reference ranges or indication of pathology, elevated levels of these enzymes may indicate their activity level in the plasma rather than liberation from cell lysis. This is consistent with Liu et al (50) , who found elevated LD for the fastest growing yellowtail kingfish in their study, consistent with its role in energetics. Likewise, the elevated AST levels for fish fed higher levels of Met found in our study are likely due to altered amino acid metabolism rather than pathology.…”

“…However, in the absence of reference ranges or indication of pathology, elevated levels of these enzymes may indicate their activity level in the plasma rather than liberation from cell lysis. This is consistent with Liu et al (50) , who found elevated LD for the fastest growing YTK in their study, consistent with its role in energetics.…”

Dietary lipid affects growth, feed utilization, liver histology and physiological biochemistry of juvenile Yangtze sturgeon, Acipenser dabryanus , an endangered sturgeon in the Yangtze River

“…It should be pointed out that the liver is an indicative organ to evaluate the nutritional and physiological status of fish, and imbalanced nutrition intake can cause disorders of liver function and clinical changes in histological status (Peng et al, 2022). In the present study, both AST and ALT activities in serum were relatively stable with the enhancement of dietary lipid, denoting that if not beneficial, this amount of lipid in this present study is probably not detrimental to juvenile Yangtze sturgeon (Liu et al, 2021). Despite that fish did not exhibit signs of “fatty liver”‐related syndrome (e.g.…”

A Chromosome-Level Genome Assembly of Yellowtail Kingfish (Seriola lalandi)

“…Since the 1990s, extensive research in Japan has focused on artificial breeding and breeding technology for S. lalandi ( Sano, 1998 ). In China, aquaculture of S. lalandi began in 2001 ( Jiang et al, 2001 ), along with biological research, including studies of embryogenesis, seedling cultivation, and effects of salinity stress on growth ( Shi et al, 2019 ; Xu et al, 2019 ; Liu A et al, 2021 ).…”