Organic acid salts, protease and their combination in fish meal‐free diets improved growth, nutrient retention and digestibility of tilapia ( Oreochromis niloticus × O. aureus )

Abstract

A study was conducted to evaluate the effects of organic acid salt blend (OAB), protease complex (Pr) and their combination (OAB+Pr) in fish meal‐free diets on growth, nutrient retention and digestibility of tilapia. Five diets were designed: a positive control (PC) diet containing 80 g/kg fish meal (FM), a negative control (NC) diet containing 0 g/kg FM and 104 g/kg meat and bone meal, and three other diets supplemented with OAB (922 mg/kg), Pr (175 mg/kg) and OAB+Pr (922 mg/kg + 175 mg/kg) to the NC diet. Tilapia with an initial body weight of 7.0 ± 0.2 g were fed the five diets for 9 weeks. The results showed that the growth performance, nutrient digestibility and retention of NC group had the lowest values among groups. Weight gain of fish fed the OAB and OAB+Pr diets was higher, and feed conversion ratio was lower (p < 0.05) compared to those fed the NC diet, while no differences with those fed the PC diet. The digestibility of dry matter, crude protein, minerals and protein retention was improved in fish fed the OAB+Pr diet (p < 0.05), but not in those fed OAB or Pr diet (p > 0.05). There were no differences in whole‐body composition and lipid retention among the treatments (p > 0.05). The supplementation of OAB and Pr alone or combined significantly increased the villi height but not the width when compared to the NC group. It can be concluded that dietary supplementation of OAB+Pr in a fish meal‐free diet improves growth and nutrient digestibility in tilapia compared to those fed the fish meal‐free diet.

Effects of Microencapsulated Organic Acid and Their Salts on Growth Performance, Immunity, and Disease Resistance of Pacific White Shrimp Litopenaeus vannamei

“…Blends of organic acids and their salts in free or microencapsulated forms have shown to improve growth performance of fish (40,57,58) In an in-vitro study, Mine and Boopathy [12] demonstrated EC50 values of 0.023%, 0.041%, 0.03%, and 0.066% for formic, acetic, propionic, and butyric acid, respectively against Vibrio harveyi. Romano et al [33] reported similar efficacy in V. harveyi resistance when fed OA supplemented diets.…”

“…Both organic acids and their salts have been used in aquafeed for better performance and disease resistance of aquatic animals [40]. The blends of organic acids used in this study are fumaric acid, sorbic acid and citric acid.…”

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

“…The supplementation of 1 g/kg metalloprotease in tilapia diet (Wu, ) and 0.175 g/kg protease (AG 175 ) in rainbow trout diet (Zhang et al, ) was reported to increase intestinal villus height, protease activity and nutrient digestibility. Also in tilapia, the fish fed a fish meal‐free diet showed a decreased villus height, which could be recovered to the normal level (80 g/kg fish meal‐containing diet) by the supplementation of protease (AG 175 ) (Huan et al, ). In another study on tilapia, the supplementation of protease (AG 175 ) in low fish meal‐pelleted diet, but not in extruded diet, significantly improved the weight gain and nutrient digestibility (Li et al, ).…”

Supplementation of citric acid in plant protein‐based diets for juvenile tambaqui, Colossoma macropomum

“…The zootechnical performance parameters were assayed as described by Cho (1992), Kaushik (1998), Hisano et al (2017), and Huan et al (2018): Weight Gain, WG (g) = final body weight (g) − initial body weight (g) Thermal Growth Coefficient, TGC (g 1/3 /°C) = 1,000 × (Wfi 1/3 − Wi 1/3 )/sum degree days Feed Conversion Ratio, FCR = feed provided (g)/weight gain (g) Protein Productive Value, PPV (%) = 100 × [(final body protein x final weight) − (initial corporal protein x initial weight)]/ total protein intake Condition Factor, CF = 100 × final weight (g)/standard length (cm) 3 …”

“…This also improves nutrient availability and, consequently, diminishes nitrogen and phosphorus being excreted into the environment because of increased nutrient digestibility (Baruah et al, 2005, 2007). However, effects of organic acids on fish are variable and dependent on factors like feeding habits, age, diet composition, management, water quality, and levels of the employed acids (Castillo, Rosales, Pohlenz, & Gatlin, 2014; Huan et al, 2018; Ng & Koh, 2016).…”