Addition of enzyme‐digested hydrolysed porcine mucosa to low‐fishmeal feed improves growth, intestinal microbiota, and intestinal peptide and amino acid transporter expressions in hybrid groupers ( Epinephelus fuscoguttatus ♀ ×  E. lanceolatus ♂)

Abstract

In this study, five iso-nitrogenous and iso-lipidic experimental low-FM diets were formulated with enzyme-digested hydrolysed porcine mucosa (EH) at concentrations of 0 g/kg (EH0, controls), 30 g/kg (EH3), 60 g/kg (EH6), 90 g/kg (EH9) and 120 g/kg (EH12). Juvenile hybrid groupers (n = 450; initial body weight 7.50 ± 0.02 g) were randomly divided into 15 tanks and fed the experimental diets twice daily for 56 days. The weight gain rate, specific growth rate, protein efficiency rate, feed conversion rate and feed intake rate of group EH3 were not significantly different from those of controls. The villus length and muscle thickness of the distal intestine (DI) in group EH12 and the villus width of the proximal intestine (PI) in group EH6 were significantly higher than those in controls. The Shannon index was significantly higher in group EH6 than in other groups. Group EH6 exhibited 17 pathway subclasses with significant differences to the other groups, comprising organismal systems (4), human diseases (6), cellular processes (2), metabolism (4) and environmental information processing (1). The expressions of CAT1, CAT2, LAAT1 and SNAT3 in the PI, and PAT1, B 0 AT3 and B0, +AT in the mid intestine (MI), and EAAT1 and PepT1 in the PI and MI in group EH6 were significantly higher than those in controls. The expressions of CAT1, CAT2, LAAT1, PAT1, SNAT3, EAAT1, B 0, + AT and PepT1 in the DI of group EH3 were significantly greater than those in controls. The maximum amount of EH that could be added to low-FM feed to improve the digestive enzyme activity and amino acid and small peptide transport ability of the DI without obviously affecting the growth performance of hybrid groupers was 30 g/kg. EH contents ≥ 60 g/kg had negative impacts on growth performance and feed efficiency.

Effect of Additives Inclusion in Gilthead Seabream (Sparus aurata L.) Diets on Growth, Enzyme Activity, Digestibility and Gut Histology Fed with Vegetable Meals

“…In the present study, no significant differences were found in CF, which is supported by the results obtained by Gao et al [48] and Yang et al [61] when they replaced FM with HPM equivalents in diets for carp and hybrid grouper, respectively. The VSI did not show significant differences either, such as in the study by Ridwanudin et al [62], in diets with dietary NT for rainbow trout, unlike Gao et al [48] and Yang et al [61], who did find that the VSI increased significantly in diets that included HPM equivalents compared with the control group. The HSI presented significant differences, where diets N250, P1, and P2 showed values close to the control diet.…”

“…Considering the SL and ML, these did not present significant differences, resulting in the smallest thickness in both parameters, obtained in the group of the control diet (AA0) with respect to the other diets. In contrast, the results obtained by Yang et al [61] in hybrid grouper feed indicate that the muscle thickness of PI in control group was significantly higher than in the groups with HPM equivalents addition. Normally, SL is the layer located on the outside of the ML, it is formed by a secretory epithelial layer (mesothelium) and another layer of connective tissue that supplies nutrients to the epithelium through blood vessels [79].…”

“…Similarly, the N500 and P2 groups showed close values. Regarding the HPM or HPM equivalents, Yang et al [61] found the addition of low doses of enzyme-digested hydrolyzed porcine mucosa (30 g kg −1 ) feasible in hybrid grouper (Epinephelus fuscoguttatus ♀× E. lanceolatus ♂) feed, as there were no significant changes in growth performance in terms of SGR, PER, and FCR compared with controls. Likewise, results obtained by Gao et al [48] suggest that dried porcine soluble, a byproduct of heparin extraction from pig intestines, can replace FM without any adverse impact on the growth performance of carp (C. carpio), thus confirming that additives greatly improve the use of vegetable diets.…”

A Novel Protein Sourced from Chinese Medicine Residue for Golden Pompano Feed: Endothelium Corneum Gigeriae Galli Residue (ECGGR)

“…It was reported that chicken intestinal hydrolysates could replace 50% of fishmeal and did not significantly affect the growth performance and intestinal immunity of common carp, Cyprinus carpio [18]. Enzymedigested hydrolyzed porcine mucosa was used to substitute for 9.1% fishmeal without negative effects on growth as well as the digestive and absorptive functions of the intestines in the hybrid grouper Epinephelus fuscoguttatus ♀ × E. lanceolatus ♂ [19].…”

Hidrolisado Proteico de Mucosa Suína como estimulante alimentar para juvenis de tilápia do Nilo

“…It is known that fish have the ability to differ the taste of chemical substances (Kasumyan & Mouromtsev, 2020), therefore it is important to observe the taste preferences of these animals so that, increasingly, studies are carried out to include foods/ingredients that can act as growth producers and improve the health of the animal, since more attractive and palatable foods can increase the consumption of the offered diets (Al-Souti et al, 2019;Jingting et al, 2020;Yang et al, 2020).…”