Seyyed Morteza Hoseini, Seyed Hossein Hoseinifar, Isa Sharifpour, Melika Ghelichpour, Abbasali Aghaei Moghaddam, Mahmoud Hafezieh,
Volume 12, Issue 3 (9-2023)
Abstract
This study was conducted to investigate the effect of adding Bacillus subtilis (IS02) to the diet on survival, biochemical indices, and histological alternations of juvenile wild common carp, Cyprinus carpio, exposed to salinity stress. Juvenile common carp (about 1.1 g) were fed diets containing 0 (control), 2.5 × 108 (pro-8), and 2.5 × 109 (pro-9) cfu/g probiotic for 15 days and then transferred directly to brackish water (13 g/L) and sampled after 3 and 10 days. Diet and sampling time had no significant effect on fish survival, which was above 96% in all treatments. Body moisture and potassium were only affected by sampling time, with moisture decreasing significantly after salinity stress while potassium increased significantly. Whole body sodium in pro-8 treatment did not change significantly during salinity stress, and probiotic treatments had lower chloride levels than the control before and after salinity stress. Adding probiotic to the diet increased glutathione reductase, glutathione peroxidase activity, and reduced glutathione concentration, while decreasing malondialdehyde concentration. Probiotics caused white blood cells infiltration in the kidney tissue. No significant tissue damage was observed in the gill and kidney, compared to the control after salinity stress. This study shows that juvenile wild common carp can tolerate direct transfer to the Caspian Sea without dietary probiotic supplementation. However, probiotic stimulates the kidney immunity, enhances ionoregulation, and increase antioxidant capacity in fish, which can have beneficial effects under field conditions.
Seyyed Morteza Hoseini, Esmail Pagheh, Abbasali Aghaei Moghaddam, Behrouz Gharavi, Melika Ghelichpour,
Volume 14, Issue 0 (2-2025)
Abstract
The aim of this study was to evaluate the effects of adding cottonseed meal along with the yeast Saccharomyces cerevisiae strain PTCC5052—either iron-enriched or non-enriched—on the economic justification of production, biochemical blood characteristics, microbial flora, and histopathological status of the intestine in juvenile rainbow trout. Fish were distributed in four treatments with four replications. One control diet without cottonseed meal, one diet containing 15% cottonseed meal, and two diets containing 15% cottonseed meal + 1 × 108 cfu/g of yeast or iron-enriched yeast were provided to the fish for 8 weeks. The results indicated no significant differences in fish production efficiency, plasma biochemical indices, and histopathological status of the intestine among the treatments. The cost of feed per unit of fish production in the treatments containing cottonseed meal significantly decreased compared to the control treatment, with the lowest cost was observed in the treatment without yeast. No significant differences in microbial abundance were observed between the control treatment and the cottonseed meal treatment; however, the addition of yeast or iron-enriched yeast to the diet resulted in an increased density of the genus Saccharomyces, a reduction in the density of the genera Aeromonas and Vibrio, and a decrease in the density of Yersinia ruckeri in the fish intestine. The results of this study indicate that adding 15% cottonseed meal to the diet of rainbow trout can enhance the economic justification for fish production, and the addition of yeast to this diet improves the microbial flora in the fish's intestine
