Cork and guar gum supplementation enhanced the buoyancy of faeces, and protease supplementation alleviated the negative effects of dietary cork on growth and intestinal health of tilapia, Oreochromis niloticus  ×  O. aureus

Abstract

To evaluate the effects of dietary cork, protease and guar gum on growth, intestinal health and faecal floatability of tilapia, fine or coarse particle cork (0.45–0.60 mm, 0.60–0.83 mm) was included in diets at 0 (control), 20 g/kg, 30 g/kg and 40 g/kg, and then, 0.175 g/kg protease (P) and 3 g/kg guar gum (G) were supplemented to the 40 g/kg coarse particle diet individually or in combination (P + G). Tilapia with an initial body weight of 15.0 ± 0.5 g were fed one of the 10 diets for 60 days. The results showed that weight gain (WG), apparent digestibility coefficient (ADC) of dry matter (DM) and crude protein (CP), intestinal evacuation ratio, intestinal digestive enzyme activity (IDE) and villus height decreased, and floating faeces ratio increased with the increasing cork level in diets. At the same supplementation level, coarse particle groups showed significantly higher floating faecal ratio than fine particle groups (p < .05). Dietary protease increased the WG, ADC of DM, IDE and villus height (p < .05), and guar gum increased floating faecal ratio when compared to 40 g/kg coarse particle group (p < .05). However, the ADC of DM, IDE and villus height of protease group were still inferior to those of control group (p < .05). In conclusion, dietary cork increased the floating faeces ratio, and the coarse particles produced more floating faeces than fine particles. Moreover, the supplementation of guar gum in cork‐supplemented diet further increased the floating faeces ratio. However, dietary cork negatively affected the growth performance of tilapia, which could be partially alleviated by the supplementation of protease.

Influences of dietary Eucommia ulmoides extract on growth, flesh quality, antioxidant capacity and collagen-related genes expression in grass carp (Ctenopharyngodon idellus)

“…The measurement of amylase activity and soluble protein concentration were used by kits (Nanjing Jiancheng Bioengineering Institute) with iodine-starch colorimetric method and Coomassie brilliant blue method, respectively, and protease activity was analyzed by Folin-Ciocalteu method. The methods were referred to the description of Yang et al [30].…”

The application of protease in aquaculture: Prospects for enhancing the aquafeed industry

“…(2016) 7.70 175 mg/kg AG175™ addition in LFD ↑ADC CP , ADC DM , and AD CP , while →ADC Ca Li et al. (2019) 15.0 175 mg/kg PT125™ (25,000 U/g) added in diets containing 40 g/kg cork ↑ADC DM and →ADC CP ; ↑Protease and amylase in the intestine Yang et al. (2019) 7.00 Supplementation of 175 mg/kg AG175™ in LFD (FM was replaced with meat and bone meal) →ADC CP , ADC DM , ADC Ca , ADC P , ADC Fe , and ADC Cu Huan et al.…”

Transcriptome Analysis of Hepatopancreas Provides Insights into Differential Metabolic Mechanisms of Eriocheir sinensis Feeding on Trash Fish and Formulated Feed

“…Metalloproteinase is a protease with good resistance to high temperature and pH and that has strong protein decomposition ability. Therefore, it has been well applied in aquatic animal feed [65,66]. Wu et al [67] carried out research on tilapia feed combined with metalloproteinase.…”