Metodik för bakteriologisk provtagning från näshålan på får
Respiratory infections are one of the major causes of disease in sheep throughout the world. In the beginning of 2008 the Swedish National Veterinary Institute and the Swedish Animal Health Service together started a project about respiratory infections in Swedish sheep. This study is an initial part of that project and the aim of this study was to investigate different sampling possibilities with focus on nasal swabs.
This study is composed partly of a literature review on causative agents of respiratory infections in sheep and existing sampling methods, and partly of an experimental study comprising 56 sheep. These sheep were sampled with both an ordinary nasal swab and a guarded nasal swab.
Before the start of this study there was to our knowledge no described method for sampling sheep with a guarded swab. Because of that the study started with composing a case which protects the swab from contaminating bacteria during entrance and exit of the nasal cavity.
The results showed that 69 % of the samples demonstrated a cleaner growth if they were taken with a guarded swab. Totally 11 isolates of M. haemolytica were found and all of them were sensitive for penicillin. The carrier prevalence for M. haemolytica in the diseased sheep varied between 5 and 40 %.