New study at the Hebrew University found that disease-resistant carp have a higher chance of survival and are also less contagious. The study's findings regarding the reduced infectivity of disease-resistant fish offer valuable insights for aquaculture and disease epidemiology. This underscores the importance of breeding disease-resistant animals to ensure sustainable food production and animal welfare. The findings suggest that selective breeding for disease resistance could be a potential avenue for developing disease-resistant carp strains in aquaculture.

A new study led by Prof. Lior David from the Faculty of Agriculture at the Hebrew University investigated the infectivity of disease-resistant and susceptible fish by examining their roles as shedders (infecting) and cohabitants (infected) in various combinations. The study focused on common carp; a species that’s commonly cultivated in aquaculture.

Infectious diseases pose significant challenges to the health and welfare of both humans and animals. While breeding genetically resistant animals is a sustainable solution for healthy food production, providing unique research opportunities, the relationship between resistance and infectivity remains poorly understood.

The study revealed that fish resistant to the virus exhibited lower viral loads in their spleens and demonstrated higher survival rates compared to susceptible fish. Susceptible fish infected by resistant counterparts experienced reduced mortality rates compared to those infected by other susceptible fish. Additionally, tanks housing resistant fish exhibited decreased viral levels in the water, leading to lower infection of other fish within the tank.

Prof. Lior David, the lead researcher of the study, commented, “The study provides experimental evidence that resistance to cyprinid herpes virus type 3 reduces infectivity due to a host mechanism that restricts viral replication and pathogen shedding. This not only benefits aquaculture production but also contributes to reducing virus propagation and disease spread in natural water bodies.”

These results demonstrate that disease-resistant fish not only survive better but also reduce the infection rate in others. This has significant implications for aquaculture production and disease epidemiology. The study highlights the importance of breeding disease-resistant animals for sustainable food production and animal welfare.