Evaluation of partial replacement of dietary animal protein from plant protein blended with glucosamine on growth and body indices of Asian Catfish (Clarias batrachus) fingerlings

Abstract

A 12- week feeding trials was conducted to evaluate the use of animal and plant protein, in combination with Glucosamine source for Asian Catfish, Clarias batrachus (av. wt. 2.2+0.009 to 2.6+0.03 g). This study was performed to evaluate the effect on fish growth performance by replacing animal protein with vegetable protein sources. In experiment, six (37.40 to 43.52 % crude protein, 16.15 to 16.76 kJ/g energy, and crude lipid 3.33 to 6.69%) practical diets were formulated. The animal and plant protein component of the diets was progressively added with glucosamine 0.5, 5.0 and 10.0% with fish meal, silkworm pupae, soybean meal and casein (F-1, PAG 0:100:0.5; F-2, PAG 0:100:5.0; F-3, PAG 0:100:10.0; F-4, PAG 50:50:0.5; F-5, PAG 50:50:5.0; F-6, PAG 50:50:10.0). The experimental moist diets were fed to triplicate groups of fingerlings at 10% of body weight and results were compared with control feed. Growth performance and feed utilization efficiency of catfish, fed diets with animal protein are better than those of plant protein supplemented feeds. After 12-week study the final weight gain recorded as 18.6g, 19.7g, 19.9g, 14.6g, 14.9g, 13.9g and 13.1g in F1 to F6 and in control fed fishes respectively. The percentage weight gain among the animal protein group (F-1, F2, F-3) were recorded as 615.4%, 756.5% and 804.5%, respectively. And the percentage weight gain in 50% replaced feeds (F-4, PAG 50:50:0.5; F-5, PAG 50:50:5.0; F-6, PAG 50:50:10.0), recorded as 563.6%, 547.8% and 479.2% respectively whereas in control it was 403.8%. The results suggests that the growth is better in total animal protein feeds and the best percentage weight gain (p<0.05) recorded in the feed F3, incorporated with 10% glucosamine (804.5%). The FCR were of the diets along with glucosamine in animal protein content has better growth performances ranged between 1.56 ± 0.03 to 1.90 ± 0.04. The survival was recorded in F1 to F6 as 88 ± 2.4%, 83 ± 2.3%, 76% ± 3.4, 74 ± 4.4%, 71 ± 2.8% and 76 ± 4.7% respectively and in control it is recorded as 68 ± 2.7%. The Hepatosomatic and Viscerosomatic indices ranged between 0.67 ± 0.03 to 1.94 ± 0.19 and 1.90 ± 0.02 to 3.17 ± 0.2 respectively in F1 to F7. The feed efficiency in terms of feed conversion ratio recorded as 1.56 ± 0.03 to 1.90 ± 0.04 among all the feeding trials. The findings shows that feed F3, containing 100% animal protein with 10% glucosamine is performed best. Results indicate that animal protein rich diets with glucosamine were much acceptable than plant protein and/or natural diets (Artemia nauplii) for Asian catfish, Clarias batrachus. And to assess the potential for replacing animal protein with soybean meal in the diets of fish need more evaluation along with synergistic approach of incorporating glucosamine.