Avaliação do desempenho do pacu (Piaractus mesopotamicus) alimentados com dietas suplementadas com mananoligossacarídeo e beta-glucana

Abstract

Fish farming in 2017 was the activity that presented the highest production of animal protein, totaling 172 million tons in the year. Pacu (Piaractus mesopotamicus) is a native fish of economic importance in Brazilian aquaculture and due to the intensification of the production system the fish are more vulnerable to pathogens and the emergence of diseases that can lead to mortality causing considerable economic losses. Prebiotics used in aquaculture contribute to the increase in animal performance and resistance to diseases, acting on the profile of the intestinal microbiota and on the health of the intestinal epithelium, which enables a better use of nutrients and the innate immune system of the host, respectively. Thus, the objective of the study was to evaluate the effect of two prebiotics, beta-glucan and MOS, on the diet of 216 Pacus (83.8 ± 12.72g) randomly distributed in 12 boxes of polyethylene (250L) and fed for 46 days, twice a day (09h00 and 16h00) until apparently satiety and the amount distributed for each box was recorded. The treatments used were: mananoligosaccharide (MOS): 0.2% inclusion, beta-glucan: 0.2% inclusion, MOS/glucan: 0.1% MOS + 0.1% beta-glucan inclusion and control diet: without prebiotic supplementation. The zootechnical performance was evaluated, and after the data were submitted to analysis of variance and when significant differences were identified they were compared by the mean test (α =0.05). In the results of the performance parameters, only the consumption of feed showed significant results in the treatments of beta-glucan: 0.2% and MOS/glucan: 0.1% MOS + 0.1% beta-glucan, which presented better results compared to the MOS treatments of 0.2% and control. The other variables analyzed as the final weight, weight gain, feed conversion index and specific growth rate did not show significant differences. Further research is needed to verify the ideal dose of inclusion for pacu specimens, as well as the ideal time of administration, and whether the inclusion of individual and aggregate prebiotics contribute to increased performance and resistance to diseases in fish.