Effect of different dietary lipid levels on the reproduction ofRhamdia quelen(Quoy and Gaimard, 1824)

Abstract

Lipids include some of the most important nutrients that affect the survival and growth of fishes in their early life stages. Lipid deficiency prior to spawning may significantly reduce egg production, hatchability and the number of surviving larvae. In this study, we investigated the effects of isocaloric diets containing 80, 140 and 200 g kg À1 of lipids (lipid source, soy oil) for 90 days. The following data were collected at 0, 45 and 90 days: final weight; length; conditioning factor; hepatosomatic, gonadosomatic and visceral fat indices; total plasma protein; testosterone; 17ß-estradiol; free amino acids; and ovary and muscle fatty acid profiles. Additionally, fecundity, oocyte production, egg morphometric parameters, and larval and postlarval growth were evaluated. Results were not statistically different for husbandry and biochemical parameters, but visceral fat content increased with increase in dietary lipid levels. The fatty acid profiles and composition differed among dietary treatments. The egg diameter and area were significantly low in fish fed the 200 g kg À1 lipid diet, thereby hindering growth, survival and weight compared to those in postlarval fish (P < 0.05). The best reproductive rates were obtained when using diets containing 80-140 g kg À1 total lipids.

Effects of dietary fatty acids on the reproduction of South American female catfish Rhamdia quelen (Quoy & Gaimard, 1824)

“…Sargent et al (2002) observed greater conversion for n-3 production, especially DHA, than for n-6 in ovary and oocyte. This is in agreement with Coldebella et al (2013) and corroborates the potential for fatty acids to be mobilized from the tissues to the oocytes (Tocher, 2003).…”

“…Few studies (Coldebella et al, 2013) focusing on fatty acids profiles of ovaries and eggs of R. quelen have been conducted using soybean oil at different levels of inclusion. The present study compared the effects of diets based on fish oil and those supplemented with soybean or palm lipids, alone and in combination with fish oil, on the growth, reproductive performance, and the fatty acid composition of ovaries and oocytes in South American catfish in their first reproductive cycle.…”

Reproductive performance of female Nile tilapia ( Oreochromis niloticus ) fed diets with different digestible energy levels

“…The effects observed for GSI and HSI corroborate the results reported by Bombardelli et al (2009), who worked with different energy levels in the diets of female Nile tilapia and also found that there were no significant effects of diet on these parameters. Coldebella et al (2013) evaluated different levels of soil oil for female catfish (Rhamdia quelen) and also observed no differences between treatments for the same variables; however, females fed diets with 140 and 200 g/kg lipids displayed greater accumulations of visceral fat. In contrast to these results, Oliveira et al (2014) observed an inverse relationship between hepatosomatic and gonadosomatic indices with a 380 g/kg crude protein level in the diet of adult female Nile Tilapia, with an initial average weight of 764 g. Table 5 -Body composition (% of dry matter) of broodstock fed diets with different digestible energy levels (mean±SEM)…”

<b>Supplementation with microencapsulated lemongrass essential oil improves protein deposition and carcass yield in silver catfish (<i>Rhamdia quelen</i>)

“…The gonadosomatic index suffers little influence from dietary components like lipids (Coldebella et al, 2013) or energy content (Tessaro et al, 2014). In silver catfish, the gonadosomatic index is strongly influenced by seasonality and, in both sexes, the gonadosomatic peak coincides with testosterone peak (Barcellos et al, 2002).…”