During a Brazilian multicentric antimicrobial resistance surveillance study, colistin resistance was investigated in 4,620 Enterobacteriaceae isolated from human, animal, food and environmental samples collected from 2000 to 2016. We present evidence that mcr-1-positive Escherichia coli has been emerging in South America since at least 2012, supporting a previous report on the possible acquisition of mcr-1-harbouring E. coli by European travellers visiting Latin American countries.

The use of antimicrobials in fish farming is a reflection of the fast aquaculture development worldwide. The intensification of aquaculture to achieve market demands could lead to an increase in infectious diseases by pathogenic bacteria. Consequently, antimicrobials act as controls for emerging infectious diseases, but their use must follow the rules and regulations of the country where the activity is performed. Although the regulations impose limits to the use of antimicrobials in fish farming, many studies show that resistant bacteria are isolated from this system. The selection of resistant bacteria is not limited only to the use of antimicrobials, but also to co-selection of resistance genes or even with cross-resistance processes. Resistant bacteria from fish farming are a serious concern because they can be acquired by humans with handling or food chain, which may represent a public health problem. In the present review, we present an overview of antimicrobials use in aquaculture, the antimicrobial resistance and the impact of antimicrobial and bacterial resistance from a public health perspective.

Background: Nile tilapia (Oreochromis niloticus), are widely used in fish farming, hormonal treatments are used to increase productivity. Studies of the characteristics of the fiber types are important in species that have well developed muscle mass, such as Nile tilapia. Methods: A total of 4800 post-larval fish were randomly assigned by tank to receive one of three treatments: Control (30 degrees GL alcohol), Homeopathic complex (Homeopatila RS) or Hormone (17-alpha-methyltestosterone) supplemented in the feed for 28 days. Survival and morphological parameters were measured at day 45. Results: At day 45, the survival rates were 54.1% (Control), 87.8% (Homeopathy), 50.3% (Hormone). The mean final weight for Homeopathy was statistically significantly lower (1.07 g) than the other two groups: Control (1.81 g) and Hormone (2.04 g). Mean total lengths were Control (4.75 cm), Hormone (4.49 cm), statistically significantly different from Homeopathy (3.83 cm). Average partial length, trunk length, height and body width were significantly lower for Homeopathy than Control or Hormone (p < 0.05) Homeopathy treated fish had significantly greater muscle fiber diameter than the other two groups. Conclusions: Fish treated with the homeopathic complex had improved survival and muscle fiber hypertrophy, but were smaller (probably related to increased survival and overcrowding) compared to fingerlings treated with synthetic hormone or control. Homeopathy (2012) 101, 154-158.

Para avaliar o efeito do probiótico (Lactobacillus sp.) associado a diferentes níveis de proteína bruta (PB) sobre o desempenho, as exigências nutricionais de PB, o rendimento de carcaça e de cortes de codornas de corte, foram utilizadas 2.304 codornas de corte, distribuídas em esquema fatorial 2 × 4 (com e sem probiótico e 15, 20, 25 ou 30% de PB), com duas repetições por nível de PB, repetido duas vezes no tempo (dois períodos experimentais), totalizando 32 unidades experimentais. A adição do probiótico reduziu o consumo de ração e melhorou a conversão alimentar no período de 1 a 7 dias de idade. De acordo com os pesos médios do modelo Linear Response Plateau (LRP), aos 7 e aos 14 dias, as estimativas de exigência foram de 27% de PB e aos 21, 28 e 35 dias, 22 a 24% de PB. A adição do probiótico não influenciou o rendimento de carcaça e de cortes. Para o rendimento de carcaça, a exigência de PB, de acordo com o modelo quadrático, foi estimada em 23,53%, mas, pelo modelo LRP, a estimativa reduziu para 17,13% de PB. Nas condições ambientais em que as codornas foram criadas, a adição do probiótico não influenciou o desempenho, as exigências nutricionais de PB e o rendimento de carcaça de codornas de corte. As exigências de PB para aves de até 14 dias de idade são de 27% e, após esta idade, reduzem para 22 a 24%.