EFFECTS OF DIETARY PROBIOTICS ON GROWTH AND HEMATOLOGICAL INDICES OF COMMON CARP (CYPRINUS CARPIO)

Abstract

Probiotics are live beneficial microorganisms that, when administered in adequate amounts, enhance the host’s health by maintaining and balancing the gut microbial community. The use of microbial probiotics is emerging in aquaculture as a sustainable strategy to enhance fish health without antibiotics. This study assessed the effects of dietary Lyophilized Saccharomyces boulardii and Shewanella putrefaciens, individually and in combination, on the growth and hematological profiles of juvenile Cyprinus carpio. A 60-day feeding trial was conducted using four treatments: a non supplemented control, L S. boulardii, S. putrefaciens, and a combination of both strains at equal concentrations. Fish were fed twice daily, growth was recorded fortnightly, and final hematological parameters including hemoglobin, hematocrit, erythrocyte and leukocyte counts, erythrocyte indices, platelet levels, and differential leukocyte counts were evaluated. Data were statistically analyzed using one-way ANOVA with post-hoc testing at p < 0.05. Probiotic supplementation significantly improved growth relative to the control, with S. putrefaciens producing the highest weight gain and specific growth rate, followed by L S. boulardii, while the combination group showed moderate improvement. Hematological assessments indicated enhanced hemoglobin, hematocrit, and red-white blood cell counts in probiotic fed fish, with no abnormal deviations in erythrocyte indices or platelet values, confirming physiological safety. All treatments maintained 100% survival. In conclusion, single-strain probiotic supplementation particularly S. putrefaciens positively influenced growth and hematological health in C. carpio. These findings support probiotics as effective, non-antibiotic tools for improving fish performance and immune competence, contributing to sustainable aquaculture practices.