Effects of dietary cellulase addition on growth performance, nutrient digestibility and digestive enzyme activities of juvenile crucian carp Carassius auratus

Abstract

This study was conducted to determine the effects of dietary cellulase addition on improving the nutritive value of Chlorella for juvenile crucian carp Carassius auratus (initial body weight: 2.99 ± 0.02 g, mean ± SEM). Five isonitrogenous and isoenergetic experimental diets were formulated to contain 0.0 (control), 0.5, 1.0, 1.5 and 2.0 g kg−1 cellulase, respectively. Each experimental diet was randomly assigned to triplicate groups with 25 juvenile fish per fibreglass tank for 8 weeks. The results showed that weight gain, specific growth rate, feed intake and the trypsin activity in the anterior intestine increased with increasing dietary cellulase to 1.5 g kg−1 and then declined with further addition. However, the mRNA expression levels of Mrf4 and Myf5, the apparent digestibility coefficients for dry matter, protein, energy and the majority of amino acids, and the activity of lipase in the anterior intestine were highest in fish fed the 1.0 g kg−1 cellulase diet, and then tended to decline with further cellulase supplementation. In conclusion, the optimal dietary cellulase supplementation level was 1.0–1.5 g kg−1, which can improve growth performance, digestive activities and nutrient digestibility in crucian carp.

Exogenous enzymes as functional additives in finfish aquaculture

“…Positive effects on the apparent digestibility of lipids were also observed when supplementing β‐glucanase to a diet containing 250 g/kg sunflower meal, or xylanase to a diet containing 260 g/kg rapeseed meal. Shi, Luo, Chen, Huang, et al () informed that dietary cellulase supplementation at the level can improve growth performance, digestive activities and nutrient digestibility in crucian carp ( Carassius auratus ). The authors revealed that cellulase is postulated to have liberated carbohydrate and protein from the endosperm cells, which increased the availability of nutrients embedded in the cell wall matrix.…”

Effect of fish meal replacement by Chlorella meal with dietary cellulase addition on growth performance, digestive enzymatic activities, histology and myogenic genes’ expression for crucian carp Carassius auratus

“…The inclusion level of cellulase in diets was based on the instruction of the producer and our recent study (Shi et al . )…”

“…In addition, when 50% of FM in diets was replaced by Chlorella meal, dietary cellulase supplementation showed positive effects on growth and feed utilization in crucian carp (Shi et al . ). Thus, on the basis of our previous study, the objective of this study was to evaluate the effects of higher cellulase levels in diets with higher fish meal substitution by Chlorella meal on growth performance, digestive enzyme activities, histology and mRNA levels of myogenic factors in crucian carp.…”

“…The application of exogenous cellulase as supplements to improve the livestock and poultry production performance and feed utilization has been studied extensively (Titi & Tabbaa ; Adeola & Cowieson ; Kuhad, Gupta & Singh ). However, there are few studies on cellulase supplementation in diets for fish (Yigit & Olmez ; Zhou, Yuan, Liang, Fang, Li, Guo, Bai & He ; Shi, Luo, Chen, Huang, Zhu & Liu ).…”

Fishmeal can be totally replaced by a mixture of rapeseed meal andChlorellameal in diets for crucian carp (Carassius auratus gibelio)

“…Crucian carp is a typical omnivorous fish, which makes a more efficient use of high levels of dietary vegetable protein (Shi, Luo, Chen, Huang, et al, 2016;Silva et al, 2010). Our recent study successfully determined the optimal dietary replacement levels of FM by Chlorella in crucian carp (Shi, Luo, Huang, Zhu & Liu, 2015).…”