Why do veterinarians ask for antimicrobial susceptibility testing? A qualitative study exploring determinants and evaluating the impact of antibiotic reduction policy.

For public health reasons, increasing attention has focused on more rational use of antimicrobials in farm animals. Guidance concerning the prescription of antibiotics and antimicrobial susceptibility testing (antibiograms in this case) are beneficial tools to help control the development of antimicrobial resistance. Nevertheless, even though there are already several qualitative studies analysing the determinants of antimicrobial prescription and use in veterinary medicine, little is known about decision-making concerning the use of antibiograms. The aim of this study was to provide a better understanding of veterinarians' motivations and role-players' influence concerning the choice of whether to ask for an antibiogram in the bovine, porcine, poultry and equine sectors in France. We concurrently evaluated the impact of a new French decree (2016) requiring an antibiogram before certain critically important antimicrobial agents can be used in veterinary medicine. Semi-structured interviews with veterinarians were conducted in France. Thematic analysis was used to analyse transcripts. In all, we surveyed 66 veterinarians. Use of antibiograms in veterinary medicine was multifactorial - 46 factors grouped into 11 categories were identified - and differed between animal sectors: use was almost systematic in poultry, frequent in pigs and rare in both the bovine and equine sectors. The decree has not increased the use of antibiograms but has induced a change in prescriptions due to field constraints and the time needed to obtain the results of antibiograms. Respondents see the decree as an aid in promoting responsible and rational use of antibiotics, fostering the use of alternatives. Our findings provide the basis of veterinarians' position regarding antibiogram use and antimicrobial resistance, pointing out levers to facilitate the use of antibiograms in veterinary medicine (for example communication on the benefits of this test and external financial support). Furthermore, the evaluation of the impact of the decree aimed at reducing the use of critically important antibiotic highlights key factors for a successful change in regulations, such as advance planning, precise and adapted communication, and demonstration of the measure's legitimacy. These results will be useful in guiding representative veterinary bodies and regulatory authorities during their decision-making, communication, and policy and regulation choices to combat antimicrobial resistance.

A case-control study on the origin of atypical scrapie in sheep, France.

A matched case-control study (95 cases and 220 controls) was designed to study risk factors for atypical scrapie in sheep in France. We analyzed contacts with animals from other flocks, lambing and feeding practices, and exposure to toxic substances. Data on the prnp genotype were collected for some case and control animals and included in a complementary analysis. Sheep dairy farms had a higher risk for scrapie (odds ratio [OR] 15.1, 95% confidence interval [CI] 3.3-69.7). Lower risk was associated with organic farms (OR 0.15, 95% CI 0.02-1.26), feeding corn silage (OR 0.16, 95% CI 0.05-0.53), and feeding vitamin and mineral supplements (OR 0.6, 95% CI 0.32-1.14). Genetic effects were quantitatively important but only marginally changed estimates of other variables. We did not find any risk factor associated with an infectious origin of scrapie. Atypical scrapie could be a spontaneous disease influenced by genetic and metabolic factors.