Effects of dietary fermentation products of kitchen waste on growth, apparent digestibility, digestive enzyme activities and serum biochemistry in juvenile allogynogenetic gibel carp (Carassius auratus gibelio) var. CAS III

Abstract

This study aimed to evaluate the effects of fermentation products of kitchen waste (FPKW) on growth, apparent digestibility, digestive enzyme activities, and serum biochemistry for juvenile allogynogenetic gibel carp “CAS III.” A total of 540 fish (7.47 ± 0.20 g/fish) were distributed among 18 aquariums at a density of 30 fish per tank in a completely randomized design (triplicated) and were fed diets containing 0, 6, 9, 12, 15, and 30% FPKW for 60 days. The results showed the weight gain rate (WGR) of fish varied quadratically with FPKW, and the WGRmax was observed when FPKW supplementation was 11.13%. Compared to the control group, the protease and lipase activities in midgut and hepatopancreas increased significantly when FPKW was 12%. The apparent digestibility of dry matter and crude protein in 30% FPKW group were significantly lower than other groups. The levels of total cholesterol, triglycerides, alkaline phosphatase, aspartate aminotransferase, and alanine aminotransferase in serum were significantly higher than other groups when FPKW was 30%. The histological examination of hepatopancreas, midgut, and kidney of fish was consistent with the growth and digestive capacity. In conclusion, there were positive effects on fish when FPKW was less than 12%.

Feeding behaviour, locomotion rhythms and blood biochemistry of the neotropical red‐tail catfish (Phractocephalus hemioliopterus)

“…We therefore hypothesized that the lower levels of cholesterol and triglycerides presented in animals fed during the day were due to the greater use of these metabolites as energy support when compared to animals fed during the night. Studies have reported that fish in conditions of greater energy demand had lower levels of cholesterol and triglycerides, using these metabolites to obtain energy (Ao et al ., 2021; Favero et al ., 2019; Santos et al ., 2021; Wu, Wen, et al ., 2018b). Cholesterol is of great importance as a constituent of membranes, ensuring fluidity and permeability in addition to being a precursor of several biologically active compounds, including bile acids, steroid hormones and vitamin D (Goedeke & Fernández‐Hernando, 2012).…”

“…Blood tests can be excellent tools to correlate the behaviour of fish with any problem or disorder that may affect them. The study of blood variables such as glucose, triglycerides, cholesterol, lipoproteins and transaminases is an essential tool in nutritional assessments as it provides important information about the fish's physiological, metabolic and health conditions (Ao et al ., 2021; Congleton & Wagner, 2006; Folmar, 1993; Šimková et al ., 2015; Wagner & Congleton, 2004). Measuring these parameters in animals fed strictly in a light or dark cycle is scarce in the literature.…”