interesting reading for members

[Duncan]

May 9, 2014

Chilean salmon industry antibiotic use




Chile: The local salmon industry is estimated to have used more antibiotics in 2013 than in the past five years. Allegedly, due the increased biomass of fish in the water. The most frequent combination was florfenicol in Atlantic salmon against SRS in the Region of Aysén.



According to the report on use of antibiotics recently published by the National Service of Fisheries and Aquaculture (Sernapesca), the local salmon industry used 450.7 tonnes of antibacterial agents in 2013, representing a 33.3 percent increase compared to the previous year (337.99 tonnes) and a 117.9 percent increase compared to 2011 (206.8 tonnes). Likewise, the industry used 143.2 tonnes of antibiotics in 2010, 184.5 tonnes in 2009, 325.6 tonnes in 2008 and 385.6 tonnes in 2007.



This means that the local use of antibiotics in 2013 is only comparable to that in those years prior to the sanitary crisis triggered by the ISA virus. Furthermore, the report of Sernapesca explains that this situation can be attributed to the higher biomass being farmed. When looking at the consumption of antibiotics in relation to the biomass of fish, both decreased after the so called "ISA crisis". And, once the biomass of fish started increasing, the consumption of antibiotics did the same.



Atlantic salmon was the species with the largest share in the use of antibiotics (70%), followed by Rainbow trout (18%) and Coho salmon (12%). Likewise, florfenicol was the antibacterial agent most frequently used (63%), followed by oxytetracycline (35%), flumequine and erythromycine, with 1 percent each. Regarding the pathogens causing use of these antibiotics in the seawater stage, the report of Sernapesca explains that 92 percent of the antibacterial products were used against SRS, followed by BKD (6%), flavobacterium and furunculosis, with 1 percent each.



Regarding geographical distribution, the Region of Aysén had the highest antimicrobial consumption with 56 percent, and followed by the Region of Los Lagos region with 41 percent and the Region of Magallanes with 3 percent.



Estimates of antibiotics used in Chile:

Year; Antibiotics Used (tonnes); Fish Average Monthly Biomass (thousands of tonnes); Consumption (%)

2007 - 385.63; 426; 0.064

2008 - 325.62; 468; 0.051

2009 - 184.47; 232; 0.039

2010 - 143.17; 256; 0.031

2011 - 206.8; 391; 0.036

2012 - 337.99; 515; 0.041

2013 - 450.7; 520; 0.057*

* Calculated over preliminary harvest figures from 2013.