Effect of ingredient particle sizes and dietary viscosity on digestion and faecal waste of striped catfish (Pangasianodon hypophthalmus )

Abstract

The ingredients' particle size and dietary viscosity may alter digestion, performance and faecal waste management of fish. This study aimed to assess the effect of grinding screen sizes of feed ingredients and dietary viscosity on digestibility, faecal waste and performance of striped catfish (Pangasianodon hypophthalmus, Sauvage, 1878). The experiment had a 2 × 3 factorial-design: two feed mesh particle sizes, by grinding ingredient mixtures at two screen sizes (0.8 versus 1.0 mm); and three dietary viscosity levels, created by exchanging carboxymethylcellulose by guar gum (GG) (0, 3 and 6 g of GG/kg of diet). Six diets were assigned to 18 tanks, each connected to three faecal settling tanks. All aquaria were stocked with 20 fish (82 g per fish). After 52 experimental days, dietary viscosity negatively affected both feed digestibility and performance of striped catfish; as a result, the amount of organic matter in the culture system through faeces had increased significantly. The coarse diets significantly increased the digestibility of dry matter and carbohydrate but worsened feed conversion ratio.Increasing dietary viscosity tended to increase the viscosity and moisture content of the faeces, but significantly accelerated the faecal disintegration through the reduction of both faecal recovery and the amount of recovered faeces. K E Y W O R D Sdigestion, faecal waste, grinding screen size, guar gum level, performance, striped catfish

Growth and physiological responses of juvenile amberjack (Seriola dumerili) fed pellet diets bound by different binders

“…Therefore, amberjack did not return to full appetite. This phenomenon probably occurs even in the case of feeding diet with small amount (0.5%) of GG supplementation combined with 2.5% AG because of GG being more viscous than AG and CMC (Tran-Tu, Hien, Bosma, Heinsbroek, and Verreth (2018)). Based on the present results of FI and GET in the amberjacks, feeding diet with more viscous binder too frequently and/or at shorter period can result in poorer FI because of prolonged GET in amberjack juvenile.…”

“…In monogastric animals such as pig, broiler, and fish, diets with higher viscosity result in slower elimination of digesta from the stomach (Rainbird & Low, 1986; Refstie, Svihus, Shearer, & Storebakken, 1999). Tran‐Tu, Hien, Bosma, Heinsbroek, and Verreth (2018) showed that increased dietary viscosity has negative effects on growth and digestibility in striped catfish, Pangasianodon hypophthalmus . When comparing the viscosity of the present test diets, it was the highest in the CMC and the lowest in the AG diets.…”

Effect of feed processing during the nursery rearing of the Nile tilapia (Oreochromis niloticus)

“…Feeds were formulated in order to meet the nutritional demands of the species in this stage of development (Table 1), according to the Brazilian tables of tilapia nutrition (FURUYA, 2010). Each nutrient in the feed was expressed with the aid of the program SuperCracr 6.1 Master (TD, 2019).…”

“…Depending on the strategy used for feed processing, fish may face difficulties during feeding, leading to significant nutrient losses, and consequently, affecting the tanks water quality negatively (RODRIGUES, FERNANDES, 2006;BITTENCOURT et al, 2012). The identification of the ideal pellet size is one of the most important aspects regarding fish nutrition (TRAN-TU et al, 2017), especially during larviculture and nursery stages, given the small size of fish (BAILEY et al, 2003), and consequently its mouth opening.…”

Effect of dietary carbohydrate to lipid ratio on performance of Nile tilapia and enhancement of natural food in pond aquaculture

“…Decreasing the CHO:LIP ratio by increasing lipid content resulted in decreased moisture and crude protein (CP) contents whereas fat and ash contents increased (Ali & Al‐Asgah, ; Haidar, Bleeker, Heinsbroek, & Schrama, ). Changing the CHO:LIP ratio can also have an impact on the apparent digestibility coefficient (ADC) of the nutrients, energy efficiency and waste composition (Amirkolaie, Verreth, & Schrama, ; Tran‐Tu et al, ). Two factors (i.e.…”