Effects of dietary glucose and starch levels on the growth, haematological indices and hepatic hexokinase and glucokinase mRNA expression of juvenile mirror carp (Cyprinus carpio)

Abstract

The effect of the different dietary carbohydrate types and levels on growth performance, haematological indices and hepatic hexokinase (HK) and glucokinase (GK) genes expression involved in control of glucose metabolism, was studied in juvenile mirror carp (Cyprinus carpio). Two carbohydrates (glucose and starch) diets with two levels (250 and 500 g kg À1 ) were fed to triplicate groups of 35 fish for 60 days. The best weight gain rate and specific growth rate were observed in fish fed with 250 g kg À1 glucose diet and 500 g kg À1 starch diet (P < 0.05). Fish fed with 500 g kg À1 glucose showed low feed utilization, with the highest food conversion ratio and the lowest protein efficiency ratio (P < 0.05). Hepatosomatic index was significantly higher in fish fed with glucose diets and the 500 g kg À1 starch diet compared to 250 g kg À1 starch. CHOL, HDL-C and LDL-C were significantly highest in fish fed with 500 g kg À1 starch than all other diets (P < 0.05). Hepatic GK mRNA expression level and activity were positively related to glucose and starch levels (P < 0.05). Correlation analysis showed that hepatic glycogen concentration was increased by dietary carbohydrate content (P < 0.05). These results suggest that GK may play a major role in the postprandial glucose utilization in juvenile mirror carp.

Effect of different sources and forms of dietary carbohydrates on growth performance, body indices and lipogenesis activity of striped catfish Pangasianodon hypophthalmus fingerlings

“…Other influential factors include differences in physiology, gastrointestinal anatomy and hormonal responses (Hung, Fynn‐Aikins, Lutes, & Xu, ). Comparing the studies is problematic in addition to the varying abilities of different fish species in glucose or starch utilization, dietary formulation, water temperature, feeding strategies and fish body size (Lee, Kim, & Lall, ; Li et al, ). Fish generally exhibit a limited capacity to metabolize extra available glucose, thereby resulting in postprandial hyperglycaemia that lasts for many hours (Small & Soares, ).…”

Use of Potato Starch in Diets of Tropical Gar (Atractosteus tropicus, Gill 1863) Larvae

“…Therefore, the present study aimed to decrease dietary protein content via substitution of potato starch, while previous studies did not change the dietary protein content by substituting a digestible carbohydrate source (corn starch) by an indigestible source (cellulose). It is well established that carbohydrate level and source show effects on growth, feed utilization and metabolism of finfish, and that these are attributable to the interaction between proteins and lipids [8,16].…”

“…Starch is a relatively complex polysaccharide; its dietary inclusion is variable, although its use is feasible in finfish diets, especially in species with omnivorous habits [7], such as common carp (Cyprinus carpio, Linnaeus 1758). Different authors reported on the use of carbohydrates (starches) with excellent results for growth and survival of freshwater carp [8]. In this context, it has been suggested that carbohydrates should not exceed 15% of the dietary dry weight for fish, because the excess of these compounds results in stunting and reduced digestibility of other nutrients [6,9].…”

“…In this context, it has been suggested that carbohydrates should not exceed 15% of the dietary dry weight for fish, because the excess of these compounds results in stunting and reduced digestibility of other nutrients [6,9]. Although it has been possible to include some digestible forms of carbohydrates in larval diets, the amount accepted and its utilization is dependent of the carbohydrate source and fish species [8]. The aim of this research was thus to assess the effects of increasing dietary levels of carbohydrates (potato starch) and decreasing protein content on growth, survival, cannibalism and digestive enzyme activities in A. tropicus larvae.…”

A strain affiliated to Bacillus amyloliquefaciens alleviates high-carbohydrate diet- induced metabolic syndrome by restoration of acetate-producing bacteria in fish intestines

“…An excess proportion of carbohydrates in their diet causes metabolic syndrome, including decreased growth performance [5], persistent hyperglycemia [6], and excess lipid deposition [7,8]. The glucose regulation mechanism in fish has been discussed in numerous studies; however, until now, most metabolic genes related to carbohydrate/glucose utilization have been found to be conserved in vertebrates [9].…”