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In response to the increasing demand for safe aquaculture products, antibiotic restrictions have prompted activists in this sector to turn to environmentally friendly alternatives. The purpose of this study was to evaluate the effect of using Tak cell probiotics containing Bacillus subtilis (IS02) at a rate of 2.5×1011 cfu/ml and superborate® (soil and water improvers) at a rate of 5-8 kg/h to increase productivity and improve production in shrimp farms in Bushehr province. Under the manufacturer's instructions, these materials were used every 7 to 10 days until the end of the rearing season. The study consisted of four treatments, each replicated three times. Thus, during the culturing period in T1 treatment, probiotic was used in combination with superborate®, and in T2 and T3 treatments, only superborate® (T2) and probiotics (T3) were used, respectively. However, no additives were used in the control treatment (T4). This study used 12 days’ post-larvae of Litopenaeus vannamei with an average weight of 0.067×0.002 g that were stocked in a 1.2-hectare pond at a density of 40 PL per m2 The study period lasted 125-120 days. The results showed that the growth and survival indices in T1 treated shrimps were 25 ± 0.04 g and 91% significantly higher than other treatment shrimps, respectively (P <0.05). However, the values obtained in T2 (21±0.14 gram, 87%) and T3 (22±0.02 gram, 90%) treatments were significantly higher than the control treatments (19±0.16 gram, 85%). Also, due to the synergistic effect of probiotics and superborate, it was observed that the frequency of pathogenic Vibrio bacteria including V.owensii (MT192348.1), V. alginolyticus (MZ854010.1), V. parahaemolyticus (MT940645.1 and MT672780.1) and V. harveyi (MT704549.1) was significantly less than other treatments at 2.30×103 cfu/ml, respectively. Therefore, according to the amount of food consumed during the rearing period, the feed conversion ratio of control shrimp with a rate of 1.72 was significantly higher than the rates of T1 (1.47), T2 (1.61), and T3 (1.52) (P <0.05). Based on the biomass produced at the end of the rearing period, it was observed that the net profit for shrimp that were treated with single-cell probiotics with superborate with 9217 million rials was significantly higher than that of shrimp treated with other treatments. Due to the synergistic effect, the combination of probiotics and superborate will, as a result, reduce the bacterial load of Vibrio in shrimp ponds, increase shrimp growth and survival rates, and increase shrimp farm profitability and production.
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