Dietary Saccharomyces cerevisiae improves survival after thermal and osmotic challenge during sexual reversal of postlarval Nile Tilapia

Abstract

This study aimed to evaluate the resistance to stress (transport, thermal, and osmotic) and growth performance of Nile Tilapia Oreochromis niloticus post‐larvae fed a diet supplemented with Yeast Saccharomyces cerevisiae. Two groups were established in triplicate: fish fed a diet supplemented with probiotic and control group without probiotic. Two hundred larvae per experimental unit were randomly distributed. Fish were fed 6 times daily. After 20 days, growth performance was determined, including survival, final weight, specific growth rate, feed conversion ratio, and effectiveness of sexual reversal. From these fish, 30 fingerlings (average weight 0,25 ± 0.02 g) per experimental unit were removed to perform stress tests (n=180), with 10 fingerlings being subjected to different stressors (i.e., transport, osmotic shock, and thermal shock). Fish fed with probiotic showed improved performance in final weight (16.6%) and survival (15.1%), as well as higher resistance to thermal (102.3%) and osmotic challenge (27.5%) compared to control fish. In addition to improved growth and survival performance, probiotic supplementation had no effect on the rate of masculinization.

Effect of the combination of fluoxymesterone and a commercial blend of additives on the sex proportion, growth, and survival of Nile tilapia (Oreochromis niloticus) fry

“…However, more work is necessary to elucidate this. Previous studies evaluating the survival of fry supplemented with commercial additives (Bio-mos ® and similar products made from Saccharomyces cerevisiae, T-Protphyt 2000, mannan-oligosaccharides, AminoGut ® , fructooligosaccharides, inulin, probiotics, and prebiotics) during a sex reversal process showed similar results compared to those shown in our work, observing no differences in survival percentages (Abdelhamid et al 2012, Mörschbächer et al 2014, de Araújo et al 2018, Rahman et al 2019 or higher survival in the additivesupplemented fish (Samrongpan et al 2008, Sakaguti-Graciano et al 2014, García-Curbelo et al 2017, Opiyo et al 2019, Pérez-Jiménez et al 2022, de la Cruz-Marín et al 2023, Faust et al 2023). These results depend on several variables (Dawood et al 2018), including species, stage of development, type of commercial additive (prebiotic, probiotic, synbiotics, blends, or immunostimulants), and concentration.…”

“…However, steroid-additive interaction and its effects on sex percentages have generally not been reported. Only a few authors have included this aspect, reporting no negative effects on the male percentage by the supplementation of an additive (Toyama et al 2000, Mörschbächer et al 2014, Rahman et al 2019, Faust et al 2023. In this respect, our work represents the first negative report of the androgen-additive interaction during the sex reversal process in Nile tilapia.…”

“…Commercial additives containing one or several of the ingredients included in the blend used in this work (cinnamon, garlic, vitamin C, inulin) have been shown to improve growth performance (Toyama et al 2000, Naftal-Gabriel et al 2019, Rahman et al 2019, Fattahi et al 2021, Habiba et al 2021, Pérez-Jiménez et al 2022, Faust et al 2023). However, in other studies, although evidence of improved health, chemical, digestive, or hematological parameters has been observed, no positive effect on growth was recorded (Kalko-Schwarz et al 2011, Abdelhamid et al 2012, Mörschbächer et al 2014, Sakaguti-Graciano et al 2014, de Araújo et al 2018, de la Cruz-Marín et al 2023.…”

Antimicrobial resistance: a concern related to streptococcosis in tilapia farming

“…Currently, a universal consensus establishes the importance of pathogen prevention and control in aquaculture (Wright et al 2023;Mougin and Joyce 2023). Diets enriched with bioproducts such as organic acids, essential oils, prebiotics, and probiotics are a reality in health maintenance in tilapia farming (Beltrán y Esteban 2022;Faust et al 2023). The use of antibiotics to control bacterial diseases in aquaculture needs feasible alternatives, as it will become unsustainable in the medium term and ineffective due to the evolution of antimicrobial resistance in pathogens, which can be transmitted to other microbes by horizontal gene transfer (HGT) via plasmids and other genetic elements from cultured fish and humans (Smith 2008;Preena et al 2020).…”