Combined effect of dietary l‐carnitine and ractopamine supplementation on growth and nutritional composition of Labeo calbasu (Hamilton, 1822)

Abstract

The study determined the combined effect of dietary l-carnitine (non-essential organic nutrient) and ractopamine (feed additive) on growth performance and nutritional composition of Labeo calbasu. To ascertain this, a 60-day feeding trial was carried out under a controlled condition where two hundred and twenty-five healthy L. calbasu fingerlings (avg. wt. 3.47 ± 0.1 g) were divided into four treatments group and one control group in triplicate. Therefore, the respective combination of l-carnitine and ractopamine diet was fed to L. calbasu fingerlings as C: control or basal feed without l-carnitine and ractopamine; T1:1 g kg−1
l-carnitine and 10 mg kg−1 ractopamine; T2: 2 g kg−1
l-carnitine and 20 mg kg−1 ractopamine; T3: 3 g kg−1
l-carnitine and 30 mg kg−1 ractopamine and T4: 4 g kg−1
l-carnitine and 40 mg kg−1 ractopamine, respectively. Upon completion of the 60-day feeding experiment, eight fish were randomly collected from each tank and subjected to a series of laboratory analyses. The study determines that T2 group fish significantly (p < .05) improved the WGP (244.66 ± 20.59%), SGR (0.89 ± 0.04), PER (2.20 ± 0.14) and increased crude protein content in fish muscle. In addition, many essential amino acids were recorded significantly high (p < .05) in the fish fed with diet T2 compared with others. Hence, dietary supplementation of l-carnitine and ractopamine at 2 g kg−1 and 20 mg kg−1 in combination is beneficial for growth and nutritional composition of L. calbasu.

Aquaculture Nutrition, Volume 27, Issue S1, Page 151-159, December 2021. Leer más