Aquaculture routinely uses fishmeal (FM) as feed, but its increasing cost has prompted the search for alternative protein sources. This study conducted an 8-week feeding trial to evaluate the effects of adding hydrolysed porcine mucosa (HPM) to low-FM feed on the growth performance, intestinal morphology, and expressions of intestinal amino acids and small peptide transporters in hybrid groupers (Epinephelus fuscoguttatus ♀ × E. lanceolatus ♂, initial weight 7.51 ± 0.03 g). Five iso-nitrogenous and isolipidic experimental diets were formulated containing HPM in proportions of 0% (Group HPM0), 3% (HPM3), 6% (HPM6), 9% (HPM9) and 12% (HPM12). Specific growth and weight gain rates were significantly lower in fish fed >6% HPM (P < 0.05). Catalase and glutamic oxaloacetic transaminase activities were significantly higher in Group HPM12 than in Group HPM0 (P < 0.05). In the distal intestine (DI), Group HPM6 had significantly higher villus length than Group HPM3, and significantly higher muscle thickness than Groups HPM0, HPM3 and HPM12 (P < 0.05). The alpha diversity index of intestinal microbiota was not significantly affected by HPM content (P > 0.05). Expressions of LAAT1 in the proximal intestine (PI), CAT2, SNAT3 and EAAT1 in the mid intestine (MI) and CAT2, B⁰AT3 and EAAT1 in the DI were highest in Group HPM3 (P < 0.05). Expressions of CAT1, CAT2, SNAT3 and EAAT1 in the PI, CAT1, PAT1, B⁰AT2 and B⁰AT3 in the MI, and PAT1 and SNAT3 in the DI were highest in Group HPM6 (P < 0.05). The expressions of PepT1 of the MI and DI were significantly higher in Groups HPM9 and HPM12 than in others (P < 0.05). The results show that adding 3% or 6% HPM to feed can improve DI morphology and increase intestinal amino acid transporter expression without reducing growth performance. Dietary supplementation with 12% HPM may improve antioxidant capacity and expression of small peptide transporters but may also cause liver damage and reduce growth performance. Therefore, HPM is a promising alternative to FM for use in aquaculture feeds.

水产养殖通常使用鱼粉（FM）作为饲料，但其成本不断上涨促使人们寻找替代蛋白质来源。这项研究进行了为期8周的饲养试验，以评估将低脂饲料添加水解猪粘膜（HPM）对杂交石斑鱼（Epinephelus fuscoguttatus）的生长性能，肠道形态以及肠道氨基酸和小肽转运蛋白表达的影响。♀×  lanceolatus E，初始重量7.51±0.03 g）。配制了五种等氮和等脂实验日粮，其中含有HPM的比例分别为0％（HPM0组），3％（HPM3），6％（HPM6），9％（HPM9）和12％（HPM12）。特定生长和体重增加率鱼显著降低供给> 6％HPM（P <0.05）。HPM12组的过氧化氢酶和谷氨酸草酰转氨酶活性显着高于HPM0组（P  <0.05）。在远端肠（DI）中，HPM6组的绒毛长度明显高于HPM3组，并且肌肉厚度也明显高于HPM0，HPM3和HPM12组（P  <0.05）。肠道菌群的α多样性指数不受HPM含量的显着影响（P  > 0.05）。的表达式LAAT1在近侧小肠（PI），CAT2，SNAT3和EAAT1中期肠（MI）和CAT2，乙⁰ AT3和EAAT1DIM中的HPM3组最高（P  <0.05）。的表达CAT1，CAT2，SNAT3和EAAT1在PI，CAT1，PAT1，乙⁰ AT2和乙⁰ AT3在MI，和PAT1和SNAT3在DI是最高的组HPM6（P  <0.05）。HPM9和HPM12组MI和DI的PepT1表达明显高于其他组（P <0.05）。结果表明，在饲料中添加3％或6％的HPM可以改善DI形态并增加肠道氨基酸转运蛋白的表达而不会降低生长性能。日粮中添加12％HPM可能会提高抗氧化能力和小肽转运蛋白的表达，但也可能引起肝脏损害并降低生长性能。因此，用于水产养殖饲料的HPM是FM的有前途的替代品。