Is there an effective way to treat bacterial diseases in fish without resistance to antibiotics?

By Maria Luiza De Grandi and Natália Martins Flores, Journalists of Ciência Rural journal, and Guerino Bandeira Junior, ter and PhD student in Pharmacology Applied to Animal Production, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil

Can essential oils be effective in treating fish disease? Based on this question, researchers from the Federal University of Santa Maria (UFSM), in partnership with the Federal University of Western Pará (UFOPA), tested the antimicrobial activity of the essential oil extracted from the Lippia origanoides plant in Jundia fish. The article “Essential plant oils against bacteria isolated from fish: an in vitro screening and in vivo efficacy of Lippia origanoides” was published in the journal Ciência Rural (vol. 49, no. 6).

The researchers conducted an in vivo assay with 120 fish. They evaluated the antibacterial activity of essential oils against bacteria isolated from kidneys and skin lesions of naturally sick fish. The essential oil of Lippia organoides presented a therapeutic success rate of 58.33% against experimentally induced aeromonose in silver catfish.

Image: BANDEIRA JUNIOR, G.

Figure 1. Comparison between a healthy fish and an infected fish

According to the researcher Guerino Bandeira Junior, the study brings advances to fish production by contributing to the discovery of new molecules with antibacterial activity. The essential oil tested can be a possible alternative to treat bacterial infections such as aeromonose in fish, a disease that affects world aquaculture. “There are few legalized antibacterial drugs for use in aquaculture and many bacterial strains are resistant to them, which requires the study of new molecules,” says the researcher.

Other similar researches also contribute to solving this issue by testing essential oils from other plants. The research group coordinated by Professor Bernardo Baldisserotto has recently developed several works in this scope. Some of them tested the antibacterial potential of phytochemicals (Bandeira Junior et al., 2018) and the essential oils of Ocimum gratissimum and Hesperozygis ringens in aquaculture (Bandeira Junior et al., 2017).

References

BANDEIRA JUNIOR, G., et al. Antibacterial potential of phytochemicals alone or in combination with antimicrobials against fish pathogenic bacteria. Journal of Applied Microbiology [online]. 2018, vol. 125, no. 3, pp. 655-665, e-ISSN: 1365-2672 [viewed 31 July 2019]. DOI: 10.1111/jam.13906. Available from: https://www.ncbi.nlm.nih.gov/pubmed/29741243

BANDEIRA JUNIOR, G., et al. Potential uses of Ocimum gratissimum and Hesperozygis ringens essential oils in aquaculture. Industrial Crops and Products [online]. 2017, vol. 97, pp. 484-491, ‎ISSN: 0926-6690 [viewed 31 July 2019]. DOI: 10.1016/j.indcrop.2016.12.040. Available from: https://www.sciencedirect.com/science/article/pii/S0926669016308706

To read the article, access it

BANDEIRA JUNIOR, G., et al. Plant essential oils against bacteria isolated from fish: an in vitro screening and in vivo efficacy of Lippia origanoides. Cienc. Rural [online]. 2019, vol. 49, no. 6, e20190064, ISSN: 0103-8478 [viewed 31 July 2019]. DOI: 10.1590/0103-8478cr20190064. Available from: http://ref.scielo.org/qqpqhg

External links

Ciência Rural – CR: <http://www.scielo.br/cr>