Detection and molecular phylogenetic analysis of chicken astrovirus in Saga prefecture, Japan.

We detected three chicken astrovirus strains in 4-day-old broiler chickens with high mortality and visceral gout and one strain from 150-day-old hens without clinical symptoms in Saga prefecture, Japan. Phylogenetic analysis based on ORF2 amino acid sequences revealed that the strains from the visceral gout cases belonged to subgroup Bi, and the strain from hens without clinical symptoms belonged to subgroup Aiii. Our study showed that CAstV had infiltrated into Saga prefecture, Japan. This is the first report of CAstV in Japan.

Contrasting gut microbiota in captive Eurasian otters (Lutra lutra) by age.

Understanding the gut microbiota characteristics of endangered species such as the Eurasian otter (Lutra lutra), especially in their early stages of life, could be essential for improving their management and ex situ conservation strategies. Here, we analyzed the gut microbiota diversity, composition, and function of captive Eurasian otters at different ages using high-throughput 16S rRNA gene sequencing. We found that: (1) Clostridiaceae was abundant in all age stages; (2) Lactococcus in cubs is thought to predominate for digesting milk; (3) bacteria associated with amino acid metabolism increase with age, while bacteria associated with carbohydrate metabolism decrease with age, which is likely due to decrease in dietary carbohydrate content (e.g., milk) and increase in dietary protein contents (e.g., fishes) with age; and (4) fish-related bacteria were detected in feces of healthy adults and juveniles. Overall, the gut microbiota of captive Eurasian otters was taxonomically and functionally different by age, which is thought to be attributed to the difference in the diet in their life stages. This study provided baseline information regarding the gut microbiota of Eurasian otters for the first time and contributes to improvement in their management in captivity.