There has never been a peer reviewed study that has shown any benefits for feeding garlic to marine fish.
Militz, T., Southgate, P., Carton, A., & Hutson, K. (2013). Dietary supplementation of garlic ( Allium sativum ) to prevent monogenean infection in aquaculture. Aquaculture, 408, 95-99.
Lee, J., & Gao, Y. (2012). Review of the Application of Garlic, Allium sativum , in Aquaculture. Journal of the World Aquaculture Society, 43(4),
Militz, T., Southgate, P., Carton, A., & Hutson, K. (2014). Efficacy of garlic ( A llium sativum ) extract applied as a therapeutic immersion treatment for N eobenedenia sp. management in aquaculture. Journal of Fish Diseases, 37(5), 451-461.
Guo, J., Kuo, C., Hong, J., Chou, R., Lee, Y., & Chen, T. (2015). The effects of garlic-supplemented diets on antibacterial activities against Photobacterium damselae subsp. piscicida and Streptococcus iniae and on growth in Cobia, Rachycentron canadum. Aquaculture, 435, 111-115.
(2015). Efficacy of an Extract from Garlic, Allium sativum , Against Infection with the Furunculosis Bacterium, Aeromonas salmonicida , in Rainbow Trout, Oncorhynchus mykiss. Journal of the World Aquaculture Society, 46(5), 569-569.
Schram, E., Pedrero, Z., Cámara, C., Van Der Heul, J., & Luten, J. (2008). Enrichment of African catfish with functional selenium originating from garlic. Aquaculture Research, 39(8),
Mohebbi, A., Nematollahi, A., Dorcheh, E., & Asad, F. (2012). Influence of dietary garlic ( A llium sativum ) on the antioxidative status of rainbow trout ( O ncorhynchus mykiss ). Aquaculture Research, 43(8), 1184-1193.
Talpur, A., & Ikhwanuddin, M. (2012). Dietary effects of garlic ( Allium sativum ) on haemato-immunological parameters, survival, growth, and disease resistance against Vibrio harveyi infection in Asian sea bass, Lates calcarifer (Bloch). Aquaculture, 364, 6-12.
Colorni, A., Avtalion, R., Knibb, W., Berger, E., Colorni, B., & Timan, B. (1998). Histopathology of sea bass ( Dicentrarchus labrax ) experimentally infected with Mycobacterium marinum and treated with streptomycin and garlic ( Allium sativum ) extract. Aquaculture, 160(1), 1-17.
I have 25 articles in my hand right now, that means there's gobs of studies out there. If you want me to include the rest of the 25, I can, but that's a lot of typing. LOL.
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