Effects of dietary l-carnitine and chromium picolinate supplementations on performance and some serum parameters in rainbow trout (Oncorhynchus mykiss)

Abstract

An experiment was conducted to determine the effects of supplemental dietary L-carnitine, chromium picolinate (Cr-Pic) and their combination on growth performance and serum total protein, cholesterol, triglyceride and glucose of rainbow trout (Oncorhynchus mykiss). A total of 276 rainbow trout were randomly allocated to four groups. Fish (average initial body weight = 151 ± 1.69 g) were fed a basal diet without supplemental L-carnitine and chromium picolinate in the control group. The basal diet was supplemented with either 500 mg/kg L-carnitine, 1.6 mg/kg chromium picolinate or 500 mg/kg L-carnitine plus 1.6 mg/kg chromium picolinate for experimental groups 1 (C), 2 (Cr-Pic) and 3 (C ? Cr-Pic), respectively. Fish were fed twice a day to apparent satiation for 58 days. Weight gain, growth rate, feed consumption and feed conversion ratio (feed/ gain) were calculated for the whole period. At the end of the study, six fish were chosen randomly from each tank to represent the experiment and frozen at -20°C for subsequent dorsal muscle analysis. The results showed no significant differences in final body weight, weight gain or feed conversion ratio among groups. There were also no significant differences in serum total protein, cholesterol, triglyceride or glucose concentrations among groups. Significantly higher lipid concentration of dorsal muscle was observed in experimental groups 1 and 3. In conclusion, supplemental dietary L-carnitine, chromium picolinate and their combination have no beneficial effects on improving growth performance and feed conversion ratio in rainbow trout. However, dietary L-carnitine slightly increased lipid concentration in dorsal muscle of rainbow trout.

Systemic regulation of L-carnitine in nutritional metabolism in zebrafish, Danio rerio

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Effects of chromium yeast, tributyrin and bile acid on growth performance, digestion and metabolism ofChanna argus

“…However, some of the studies differ from these results. In rainbow trout ( Oncorhynchus mykiss ), TG and TCHO in the serum were not significantly different after supplementation with chromium picolinate, meaning that this compound was not beneficial for elevating growth performance and feed conversion ratio (Selcuk, Tiril, & Alagil, ). In Nile tilapia, different chromium supplements did not affect serum TCHO concentrations (Pires et al, ).…”

The metabolic regulation of dietary L‐carnitine in aquaculture nutrition: present status and future research strategies

“…The lack of L‐carnitine influences on growth may be attributed to dietary L‐carnitine content in diets (Selcuk et al . ; Zheng et al . ) (Kuka et al .…”