Reproductive performance of silver catfish fed sorghum diets supplemented with phytase

Abstract

-The objective of this work was to evaluate the reproductive performance of silver catfish (Rhamdia quelen) fed diets containing sorghum, as a replacement for corn, supplemented or not with phytase. The experiment was carried out with 360 fish, with 16.02±0.58 g mean initial weight, fed diets in which low-tannin sorghum replaced corn at 0, 50, and 100%, with or without phytase supplementation (1,500 FTU per kilogram of feed). Diets supplemented with phytase or with 100% sorghum led to a reduction of visceral fat deposition and hepatic mass in males. In females, similar results were observed for diets containing phytase. Females fed sorghum-only diets, supplemented or not with phytase, had bigger oocytes. Males and females at the developing and final stages of gonadal maturation were found in all treatments. The replacement of corn by sorghum affects neither semen quality nor the fertilization rate of gametes. Therefore, complete replacement of corn with low-tannin sorghum in the diet can be performed without compromising the reproductive performance or the somatic indexes of silver catfish.Index terms: Rhamdia quelen, alternative food, breeding nutrition, histology, quality of gametes. Desempenho reprodutivo de jundiá alimentado com dietas com sorgo suplementadas com fitaseResumo -O objetivo deste trabalho foi avaliar o desempenho reprodutivo de jundiá (Rhamdia quelen) alimentado com dietas contendo sorgo em substituição ao milho, suplementadas ou não com fitase. O experimento foi realizado com 360 jundiás, com peso médio inicial de 16,02±0,58 g, alimentados com dietas compostas por 0, 50 e 100% de sorgo de baixo tanino, em substituição ao milho, com ou sem a suplementação de fitase (1.500 UFA por quilograma da dieta). Dietas com suplementação de fitase ou com 100% de sorgo reduziram a deposição de gordura visceral e a massa hepática nos machos. Nas fêmeas, o mesmo efeito foi observado quanto às dietas com suplementação de fitase. As fêmeas alimentadas com dietas apenas com sorgo, suplementadas ou não com fitase, apresentaram ovócitos maiores. Foram encontrados machos e fêmeas nas fases finais de desenvolvimento e maturação gonadal, em todos os tratamentos. A substituição do milho pelo sorgo não afeta a qualidade seminal nem a taxa de fertilização dos gametas. Portanto, a substituição completa do milho pelo sorgo de baixo tanino pode ser efetuada sem afetar os parâmetros reprodutivos e os índices somáticos do jundiá.Termos para indexação: Rhamdia quelen, alimento alternativo, nutrição de reprodutores, histologia, qualidade de gametas.

Probiotic effects (Bacillus cereusandBacillus subtilis) on growth and physiological parameters of silver catfish (Rhamdia quelen)

“…The silver catfish ( Rhamdia quelen ) became one of the most studied native species by presenting expressive growth, excellent feed conversion, tolerance to handling, high carcass yield and reproductive viability when reared in captivity (Amaral‐Junior et al., 2008; Barcellos et al., 2004; Carneiro et al., 2006). In addition, its high acceptance in the consumers market has increasing the number of rearing facilities, which can be performed either in excavated ponds or net‐cages, from the initial stages to termination, presenting optimal growth throughout all year, even during periods of low temperatures (Amaral‐Junior et al., 2015; Diemer et al., 2012; Rodrigues, Sanchez, et al., 2017; Signor et al., 2013).…”

Reproductive physiology of Rhamdia quelen is improved by dietary inclusion of probiotics

“…Fertilization was performed using the dry method (Zaniboni‐Filho & Weingartner, 2007), with a homogenization between oocytes and semen (pool of the same treatments). Posteriorly, 100 ml of eggs from each female was transferred into 20‐L experimental incubators disposed in a water recirculation system (mean temperature of 26°C), until the larvae hatched (Bittencourt et al., 2018; Diemer et al., 2014; Rodrigues, Sanches, et al., 2017).…”