Antimicrobial drug use in Austrian pig farms: plausibility check of electronic on-farm records and estimation of consumption

Abstract

Electronic drug application records from farmers from 75 conventional pig farms were revised and checked for their plausibility. The registered drug amounts were verified by comparing the farmers' records with veterinarians' dispensary records. The antimicrobial consumption was evaluated from 2008 to 2011 and expressed in weight of active substance(s), number of used daily doses (nUDD), number of animal daily doses (nADD) and number of product-related daily doses (nPrDD). All results were referred to one year and animal bodyweight (kg biomass). The data plausibility proof revealed about 14 per cent of unrealistic drug amount entries in the farmers' records. The annual antimicrobial consumption was 33.9 mg/kg/year, 4.9 UDDkg/kg/year, 1.9 ADDkg/kg/year and 2.5 PrDDkg/kg/year (average). Most of the antimicrobials were applied orally (86 per cent) and at group-level. Main therapy indications were metaphylactic/prophylactic measures (farrow-to-finish and fattening farms) or digestive tract diseases (breeding farms). The proportion of the 'highest priority critically important antimicrobials' was low (12 per cent). After determination of a threshold value, farms with a high antimicrobial use could be detected. Statistical tests showed that the veterinarian had an influence on the dosage, the therapy indication and the active substance. Orally administered antimicrobials were mostly underdosed, parenterally administered antimicrobials rather correctly or overdosed.

FIG 1:

Exceeding of the threshold value (threshold value=q₇₅+(1.5×IQR) (Tukey 1977)) for the antimicrobial consumption (in number of animal daily doses per kg biomass per year - nADD_kg/kg/year) in 49 farrow-to-finish farms from 2008 until 2011. Ratios were calculated by dividing the antimicrobial consumption per farm by the threshold value. Consequently, a ratio of 1 represents an antimicrobial consumption equal to the threshold value. In the figure, farms with a higher consumption than the threshold value (‘outlier farms’) are coloured. Farms are sorted by their total consumption in four years