Effects of different feed stimulants on freshwater crayfish (Procambarus clarkii), fed diets with or without partial replacement of fish meal by biofeed

Abstract

The feeding trials were carried out with freshwater crayfish (Procambarus clarkii) to evaluate the three feed stimulants betaine (Bet), squid extract (SE) and squid meal (SM) upon fish meal (FM) diets or biofeed (BF) diets in which FM were partially replaced by BF. Results showed the three feed stimulants had no significant effect on growth. By the relative concentration of markers in the faeces and diets, the preference for each diet was estimated, and the best stimulant was the mixture of Bet, SE and SM. As FM replaced by BF increased, added with the mixture, the relative weight gain showed an increasing trend, but decreased significantly by 30% replacement. With the substitution increasing, trypsin activities increased, whereas decreased too upon 30% substitution. Less than 30% replacement, there was no significant effect on muscle proximate composition, intestine amylase activities and serum haemocyanin contents, except the drop of lipid. The results indicated that the mixture of Bet, SE and SM could perform well as a feed stimulant. And with the addition of the mixture, FM in the diet could make about no more than 20% saving without any adverse effects. 3 Biofeed (g kg À1 ): crude protein 437, crude lipid 58, calcium 17, phosphorus 16.7, moisture 120 and ash 170. 4 Other components (g kg À1 ): rapeseed meal 100, soybean meal 93, vinasse 80, cottonseed meal 40, corn protein 60, flour 180, soybean oil 18, fish oil 18, mineral mixture 5, vitamin mixture 5, calcium dihydrogen phosphate 15, compound phosphatide 20, moult hormone 1, choline 1, dextrin 10, gelatine 40 and markers: diets of the same group (fish meal or biofeed) were marked with 100 mg kg À1 of the oxides of rare earth element, respectively (

Effects of four feeding stimulants in high plant-based diets on feed intake, growth performance, serum biochemical parameters, digestive enzyme activities and appetite-related genes expression of juvenile GIFT tilapia (Oreochromis sp.)

“…Feeding stimulants, which do not necessarily have a dietary value but modify the flavour of feed, are sometimes used in fish feed to improve palatability and increase FI. Numerous studies have demonstrated that some specific compounds like L‐amino acids, betaine (Bet) analogues, nucleotides and marine extracts are potent FS in aquatic feed (Hua et al., ; Johnson & Atema, ; Lall & Tibbetts, ; Luo, Tan, Liu, & Wen, ; Nakajima, ). Bet [(CH 3 ) 3 N + CHCOOH] has been proven as efficient FS or attractant for fish (Luo et al., ).…”

Replacing fish meal with vegetable protein sources in feed for juvenile red swamp crayfish, Procambarus clarkii : Effects of amino acids supplementation on growth and feed utilization

“…Red swamp crayfish ( Procambarus clarkii ) is now widely cultured in China because of the delicious taste and high consumer demand (Hua et al., ). Studies on nutrient requirements, dietary energy to protein ratios, plant protein utilization and diet formulation of this crayfish have been conducted (Huner, ; Huner & Meyers, ; Jover, Fernández‐Carmona, Del Rı́o, & Soler, ; Reigh, Braden, & LaPrarie, ; Wiernicki, ; Xu, Wang, Wang, & Peng, ).…”

“…Studies on nutrient requirements, dietary energy to protein ratios, plant protein utilization and diet formulation of this crayfish have been conducted (Huner, ; Huner & Meyers, ; Jover, Fernández‐Carmona, Del Rı́o, & Soler, ; Reigh, Braden, & LaPrarie, ; Wiernicki, ; Xu, Wang, Wang, & Peng, ). Although soybean meal shows higher protein and energy digestibility for red swamp crayfish (Reigh, Braden, & Craig, ), the palatability and attractiveness of diet decreased once fish meal in the diet of red swamp crayfish was replaced by alternative protein sources (Hua et al., ). Information regarding the inclusion of soybean meal and rapeseed meal as well as crystalline amino acid in the feed for red swamp crayfish is still limited known.…”

Effects of Different Diet Types on Growth and Survival of White-Clawed Crayfish Austropotamobius pallipes in Hatcheries

“…Studies on the palatability of diets have shown crustaceans will increase their feeding when particular stimulants are added to their diet (Harpaz et al, 1987;Hua et al, 2015). Crustacean species within aquaculture have preferences for specific textures and softness of food items (Cox and Johnston, 2003).…”

“…Several studies have examined feeding and nutrition requirements of captive-bred crayfish, including P. leniusculus (Carral et al, 2011;González et al, 2012), red swamp crayfish Procambarus clarkii (Hua et al, 2015) and common yabby Cherax destructor (Austin et al, 1997). Commercially available fish-feed pellets were historically fed to all age-classes resulting in low survival rates of hatchlings in both A. pallipes (Sáez-Royuela et al, 2001) and P. leniusculus (Ulikowski et al, 2006;Sáez-Royuela et al, 2007).…”