Antimicrobial Consumption in Medicated Feeds in Vietnamese Pig and Poultry Production

Abstract

Antimicrobials are extensively used as growth promoters in animal feeds worldwide, but reliable estimates are lacking. We conducted an internet-based survey of commercial chicken and pig feed products officially approved for sale in Vietnam over the period March–June 2015. Information on the antimicrobial contents in feed products, alongside animal production data, was used to estimate in-feed antimicrobial consumption to produce one kilogram of live animal (chicken, pig), as well as to estimate country-wide antimicrobial consumption through animal feeds. A total of 1462 commercial feed formulations were examined. The survey-adjusted estimated antimicrobial contents were 25.7 and 62.3 mg/kg in chicken and pig feeds, respectively. Overall, it was estimated that 77.4 mg [95% CI 48.1–106.8] and 286.6 mg [95% CI 191.6–418.3] of in-feed antimicrobials were used to raise 1 kg of live chicken and pig, respectively. Bacitracin (15.5% feeds), chlortetracycline (11.4%), and enramycin (10.8%) were the most common antimicrobials present in chicken feed formulations, whereas bacitracin (24.8%), chlortetracycline (23.9%), and florfenicol (17.4%) were the most common in pig feed formulations. Overall, 57% of the total quantitative usage consisted of antimicrobials regarded by WHO of importance for human medicine, including amoxicillin, colistin, tetracyclines, neomycin, lincomycin, and bacitracin. These figures confirm a very high magnitude of in-feed consumption of antimicrobials, especially in pig production. Results from this study should encourage further monitoring of antimicrobials used in animal production, and foster discussion about existing policies on inclusion of antimicrobials in animal feed rations.

Antimicrobial Usage and Antimicrobial Resistance in Animal Production in Southeast Asia: A Review

“…Six publications [15,16,17,18,19,20] reported AMU in terrestrial animal production (pigs and chickens), and two in aquaculture production [21,22]. Except for one publication that investigated antimicrobial use to raise chickens in integrated fish–chicken farms [21] in Thailand, and another one that investigated fish and shrimp farms in both Thailand and Vietnam [22], the remaining publications investigated AMU exclusively in Vietnamese farms.…”

“…Overall, it was estimated that 286.6 mg and 77.4 mg of in-feed antimicrobials were used to raise 1 kg of live pig and chicken, respectively. Bacitracin (in 15.5% of formulations), chlortetracycline (11.4%), and enramycin (10.8%) were the most common antimicrobials present in chicken formulations, whereas bacitracin (24.8%), chlortetracycline (23.9%), and florfenicol (17.4%) were the most common in pig feed formulations [19]. …”

“…In the EU, a total of 11 non-ionophore AGPs have been used historically, with no more than three to four antimicrobials available at any given time, none of them listed by WHO as “critically important” [116]. In contrast, a recent study of commercial pig and poultry feed products in Vietnam found 14 different AGPs that included colistin, amoxicillin, and neomycin [19]. …”

“…The recent increase in reports of invasive infections caused by mcr- 1 plasmid-mediated colistin resistance worldwide is of great concern [123]. Since this antimicrobial is currently used as AGP in Vietnam (and possibly in other countries), the restriction of this antimicrobial should be a priority [19]. Data is not available on carbapenem resistance testing among isolates in the region.…”

Reduction of antimicrobial use and resistance needs sectoral-collaborations with a One Health approach: perspectives from Asia

“…Asia's population represents a large portion of this global cohort, with intensive agriculture production systems, making it a large and significant consumer and user of antimicrobials. In Vietnam, it is estimated that over 2000 tonnes of antimicrobials are used for feed production for chicken and pig annually (Van Cuong et al 2016). Three countries (Vietnam, Thailand and China) use onethird of antimicrobials worldwide in livestock production (Van Boeckel et al 2015).…”