Loss of gut microbial diversity in the cultured, agastric fish, Mexican pike silverside (: Atherinopsidae).

Teleost fish are the most diverse group of extant vertebrates and have varied digestive anatomical structures and strategies, suggesting they also possess an array of different host-microbiota interactions. Differences in fish gut microbiota have been shown to affect host development, the process of gut colonization, and the outcomes of gene-environment or immune system-microbiota interactions. There is generally a lack of studies on the digestive mechanisms and microbiota of agastric short-intestine fish however, meaning that we do not understand how changes in gut microbial diversity might influence the health of these types of fish.

Cannibalism rate and mLeptin expression are influenced by photoperiod and diets in Piracanjuba, Brycon orbignyanus (Valenciennes, 1850) larvae.

Piracanjuba (Brycon orbignyanus) is a species with great productive potential, and during its larval phase, it presents intense cannibal activity. The photoperiod and diet are primary feed behaviour and cannibalism modulators to fishes. This experiment aimed to verify the effect of different photoperiods and diets in Piracanjuba larviculture.

Sperm characterization and cryopreservation of the endangered freshwater fish Chirostoma estor (Atheriniformes).

The knowledge of the physiology of sperm of an endangered species allows the implantation of reproductive biotechnologies that aim at conservation. The aim of this study was to characterize fresh sperm and evaluate different cryopreservation solutions for sperm in Chirostoma estor. The characterization of Chirostoma estor fresh sperm (n = 22 males) was performed through analyzes of sperm concentration, membrane integrity, sperm morphology, motility rate, motility quality score, and motility duration.