Bacteria that harm fish farms found in Brazil for first time

Topic: Biology

Scientists have discovered bacteria that cause a serious disease in farmed fish. The disease was previously only seen in Asia and the US. The bacteria were found in fish farms in Brazil, including those raising native Brazilian species.

For the first time in Brazil, scientists have identified the presence of bacteria that cause columnaris disease, a serious disease in farmed fish intended for human consumption.

This disease primarily affects farms raising Nile tilapia (Oreochromis niloticus), also known commercially as Saint Peter. However, it also affects farms raising native Brazilian species, such as tambaqui, pacu and Amazon spotted catfish.

The bacteria that cause columnaris disease are part of the genus Flavobacterium. Until recently, four species of this genus were considered a single species: Flavobacterium columnare. This is where the name of the disease comes from.

Columnaris disease causes whitish lesions on the skin and fins, as well as necrosis in the gills of fish. The bacteria feed on epithelial cells and kill the fish within a few days, especially larvae and fry.

Why It Matters

This discovery is important because it highlights the need for better surveillance and vaccine development to protect Brazil's fish farms from this disease.

Key Facts

• Scientists have identified the presence of bacteria that cause columnaris disease in Brazilian fish farms.
• The disease was previously only seen in Asia and the US.
• The bacteria were found in farms raising Nile tilapia, as well as native Brazilian species like tambaqui and pacu.
• Columnaris disease causes whitish lesions on the skin and fins of fish, and can kill them within a few days.
• The discovery highlights the need for better surveillance and vaccine development to protect Brazil's fish farms.

Key Terms

Flavobacterium

A genus of bacteria that cause columnaris disease in farmed fish

Columnaris disease

A serious disease caused by Flavobacterium bacteria that affects farmed fish

Implications

This discovery is important because it highlights the need for better surveillance and vaccine development to protect Brazil's fish farms from this disease.