Effect of dietary lysine on growth, intestinal enzymes activities and antioxidant status of sub-adult grass carp (Ctenopharyngodon idella)

Abstract

The dietary lysine requirement of sub-adult grass carp (460 ± 1.5 g) was assessed by feeding diets supplemented with grade levels of lysine (6.6, 8.5, 10.8, 12.9, 15.0 and 16.7 g kg(-1) diet) for 56 days. The test diets (28% CP) contained fish meal, casein and gelatin as sources of intact protein, supplemented with crystalline amino acids. Weight gain (WG), feed intake and feed efficiency were significantly improved with increasing levels of lysine up to 12.9 g kg(-1) diet and thereafter declined (P < 0.05). Quadratic regression analysis of WG at 95% maximum response indicated lysine requirement was 10.9 g kg(-1) diet. Activities of trypsin, chymotrypsin, lipase, Na(+), K(+)-ATPase and alkaline phosphatase in intestine, creatine kinase activity in proximal and mid-intestine responded similar to WG (P < 0.05). In addition, lipid and protein oxidation decreased with increasing levels of lysine up to certain values and increased thereafter (P < 0.05); the anti-hydroxyl radical capacity, dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione-S-transferase (GST) activities and glutathione content were increased with increasing dietary lysine levels up to certain values in the detected tissues, except for hepatopancreatic GST. Requirement estimated on the basis of malondialdehyde content in intestine and hepatopancreas was 10.6 and 9.53 g lysine kg(-1) diet, respectively.

Effects of lysine and methionine supplementation on growth, body composition and digestive function of grass carp (Ctenopharyngodon idella) fed plant protein diets using high-level canola meal

“…; Li et al . ). Dietary antinutritional factors have been reported to adversely affect the digestibility of protein, bioavailability of amino acids and protein quality of foods (Sarwar et al .…”

“…Trypsin, lipase, amylase, creatine kinase (CK), Na + /K + ‐ATPase, alkaline phosphatase (AKP) and γ‐glutamyl transpeptidase (γ‐GT) activities were determined according to the procedure described by Li et al . (). The protein content of tissue samples was determined as described by Bradford ().…”

“…; Li et al . ). Previous studies indicate that plant meals are an important replacement protein source for FM in extruded fish feeds (Carter & Hauler ; Zhang et al .…”

Dietary tryptophan modulates intestinal immune response, barrier function, antioxidant status and gene expression of TOR and Nrf2 in young grass carp (Ctenopharyngodon idella)

“…However, the effects of Trp on the non-enzymatic capacity in fish have not been demonstrated in other reports. Our previous studies indicated that nutrients, such as histidine [90] and lysine [91], increased the GSH content in the intestine of fish. Additionally, SOD and GPx are the major antioxidant enzymes in fish [92].…”

Catalase, superoxide dismutase, glutathione peroxidase and oxygen radical absorbance capacity in the gut of juvenile pacu Piaractus mesopotamicus and dourado Salminus brasiliensis fed bovine first milk secretion

“…Tang et al (2013) showed that the increase in the activity of antioxidant enzymes in the intestine of the young grass carp Ctenopharyngodon idella is related to decrease in lipid peroxidation and protein oxidation, resulting in enhanced intestinal defense. Similar to colostrum, amino acids also increase the intestinal activity of antioxidant enzymes (Li et al, 2014;Hong et al, 2015). Jiang et al (2010) also observed that the inclusion of components that inhibit free radical generation (myo-inositol) in the diet of Jian carp (Cyprinus carpio var.…”