Bacterial Infection in Farmed Barramundi Juveniles, Lates calcarifer

Abstract

In 2016, Barramundi, Lates calcaifer juveniles imported from Thailand to the aquaculture station at Sultan Qaboos University exhibited remarkable external clinical signs of losing scales, severe muscle necrosis, and ascites. Fin rot was also observed in the diseased fish. The mortality reached more than 90 % and it was assumed that certain bacterial species were associated with the diseased fish. The objective of the present study was to investigate the infection route of disease, revealing the causative agent and finding the most effective antibiotic treatment. The suspected pathogen vehicle was mosquito larvae in the outlet of the culture tank as bacterium was isolated inside the mosquito larvae. Primary, traditional phenotypic tests and the vitic test confirmed that the bacteria were pathogenic Aeromonas sobria and Lactococcus garvieae. Eight of the most commonly used antibiotics in the aquaculture industry was used for antibiotic susceptibility test. It showed that that Gentamycin was the most effective antibiotic while the most effective environmentally friendly source was henna, Lawsonia inermis, at a concentration of 10%.

The haematology of clinically healthy, farmed juvenile Asian seabass (Lates calcarifer Bloch)—reference intervals, and indicators of subclinical disease

“…This study aims to establish baseline blood RIs for clinically healthy, farmed juvenile L. calcarifer . Juvenile fish in intensive aquaculture are more susceptible to disease, due to developing immune systems (Al Khaziri et al, 2019; Azad et al, 2004; Bastos Gomes et al, 2017; de Groof et al, 2015; Dong et al, 2017; Fenner et al, 2006; Gibson‐Kueh et al, 2011). The blood parameters analysed and methods used are selected based on their practical applications in commercial farms.…”