Effects of dietary soybean meal levels on reproduction parameters, the growth and gonad, gut, hepatopancreas histology of female African Cichlids Pseudotropheus socolofi

Abstract

This study was conducted to determine the effect of different soybean meal dietary supplementation levels on the growth, reproductive parameters, gonad, intestine and hepatopancreas histology of Pseudotropheus socolofi. Experimental groups were hand-fed to satiety with diets supplemented with soybean meal at levels of 3, 16, 27, 35, and 44% twice daily for 90 days. The results of this study showed that specific growth rate, weight gain, and survival rate were not affected by dietary soy proportions (P > 0.05). The worst FCR and final weight were found in those fed the diet containing 44% soy (P < 0.05). In female reproductive parameters, there was no significant difference between the groups in fertilization rate, egg production, hatching rate, egg diameter, gonadosomatic index and broodstock ovulation percentage (P > 0.05). However, due to pathological examinations in female individuals, a significant decrease was observed in the number of mature oocytes in the ovaries and goblet cells in the intestines with increasing soy levels in the diet (P < 0.05). As a result, using soybean meal up to 35% did not negatively affect growth. However, adding 44% soybean meal to diets caused histopathologically serious inflammatory reactions and decreased growth.