A Metagenomic analysis of weight gain in Zebrafish exposed to Amoxicillin

Antibiotics are widely being used in different fields, increasing productivity or treating diseases. These antibiotics are being released in nature or given to humans without any information on how they will affect the different ecosystems such as rivers and gut microbiomes. Amoxicillin is one of the most prescribed broad-spectrum antibiotics, especially to children, to treat respiratory infections. However, its effects on the microbiome have not been studied. In this study I focused on the effects of amoxicillin on the gut microbiome of zebrafish and how it affected weight gain and growth development. We separated the zebrafish into a high calories and low calories groups and exposed them to 2 concentration of amoxicillin over 3 weeks, dissected the guts, and performed a metagenomic analysis of the 16S v4 region of the guts DNA. My results have shown that low antibiotic doses lead to an increase in weight gain and growth, particularly in the 1 week of the experiment. The high antibiotic dose had an increased sensitivity to Tricaine, an anesthetic used to measure and weight the fish, after 1 week of exposure. The microbiome was shifted due to the interaction of the diet and antibiotics, leading to a reverse trend of Fusobacteria and Proteobacteria between both diet and antibiotics. These results indicate that both amoxicillin doses combined to the two diets were able to influence the microbiome and although they gave different outcomes