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Antibiotic Use in period 2005-2012 in Dairy Herds in The Netherlands, with outlook to some other Countries
Use of antibiotics in animals has become part of the societal discussion. National goal was to reduce use by 50% in 2013 compared to 2009. A herd health and treatment plan have been introduced. From 2012 on 3/4 generation drugs (3/4GE) are only allowed in exceptional cases. To gain insight, antibiotic use and attitudes of farmers were examined on 94 farms during period 2005-2012. Number of Daily Dosages (NDD) indicates how many days per year an average cow in the herd is under treatment of antibiotics. NDD was on average 5.86 (SD 2.14). The NDD level was increasing in period 2005 through 2007, followed by a period of growing societal interest in animal antibiotic use resulting in a reduction in use in 2011-2012. On average, 68% of NDD was applied to the udder, dealing with mastitis (25%) and dry-cow therapy (43%). Drugs other than applied to udder health tended to decrease the most, while farmers were reluctant to lower use of dry-cow therapy tubes. Use of 3/4GE drugs minimized from 18% of NDD in period 2005-2010 to 1% in 2012. More use of penicillin’s and wide spectrum drugs took place. The drop in NDD use varied between 3 groups of farmers studied. The guided study groups reduced usage since 2007, the environmental group (not guided) had a significant drop in use in 2011 and the incidental group (not guided) in 2012. Reduction in use was modelled applying the Rogers diffusion of innovation theory. A logistic function fitted nicely to the adaptation process including the early adapters and late majority groups of farmers. Also farm and herd factors affecting antibiotics use were studied, practising a step-wise regression procedure. Variation in total use and dry cow therapy were explained, respectively, for 39 and 46 % by factors such as quota size, milk amount/cow, health status, cell count and calving interval. A correlation of -0,55 between cell count and NDD was found. The “more successful and entrepreneurial ” farmers, with a good relation to the veterinarian, tended to use somewhat more antibiotics than the other colleagues. They were also able to adapt more easily to the new conditions. The situation in some other countries is compared to the analysis above. Especially Denmark, with a quite different focus on antibiotic use, is of interest in this respect.
Keywords:
Antibiotic use, Dairy herds, Farm factors