in Tambaqui (): A Pathogenicity, Antimicrobial Susceptibility, and Genetic Analysis of Brazilian Isolates.

is a crucial pathogenic bacterium in tropical aquaculture. This bacterium was recently isolated from tambaqui (), a commercially important fish species in Brazil. This study assessed the antimicrobial susceptibility, pathogenicity, and genetic diversity of the tambaqui-derived isolates.

Short-term preservation of Colossoma macropomum oocytes by different methods and chilling temperatures.

A preservation protocol has not been established for Colossoma macropomum oocytes, and its development may improve the production and breeding programs of this South American fish species. Thus, this study aimed to determine the effect of different methods and protocols for the preservation of C. macropomum oocytes.

Effects of melatonin supplementation on the quality of cryopreserved sperm in the neotropical fish Prochilodus lineatus.

The cryopreservation process causes damage to sperm structures and supplementation of the cryoprotective medium is an alternative to reduce these damages. The aim of this study was to determine the effect of melatonin supplementation on post-thaw sperm quality in Prochilodus lineatus. The cryoprotective medium was supplemented with 2.

Melatonin administration attenuates acute stress by inducing sleep state in zebrafish (Danio rerio).

Melatonin plays a fundamental homeostatic role in basic biological functions, and an anti-stress role has been also proposed for this hormone. This study aimed to evaluate hormonal, enzymatic and behavioral parameters of zebrafish that received administration of melatonin and were submitted to acute stress. A total of 120 wild-type zebrafish were divided into five groups: naïve control (N), negative control group (Stress/C), positive control treated with diazepam (Stress/Diaz), treatment with melatonin at dose 1 (Stress/Melt.

Effect of melatonin supplementation to a cytoprotective medium on post-thawed Brycon orbignyanus sperm quality preserved during different freezing times.

The aim of the present study is to verify the viability of frozen B. orbignyanus sperm cells after freezing with dilution media containing different concentrations of the melatonin and after different freezing times. Semen from 15 males was collected and pooled as five pools from three random animals.