| dc.description.abstract | The production and performance of an animal will be affected by an infection or disease that involves vital organs. Pneumonia is such a disease and is common to find in sheep, not only in Norway but in the whole world. Bacteria species such as Mycoplasma ovipneumoniae, Mannheimia haemolytica, and Bibersteinia trehalosi have all been isolated from pneumonic lungs in sheep. The Norwegian Veterinary Institute has reported that pneumonia counts for 10% of the diagnosis set at macroscopical examination of sheep some years. It is a disease that is difficult to treat and is potentially life-threatening. To find an optimal treatment method in a herd, it is beneficial to know which is the causing agent of pneumonia.
The aim of this project was firstly to investigate lungs with signs of pneumonia for the presence of M. ovipneumoniae, M. haemolytica, and B. trehalosi. The second aim of this project was to investigate the composition of bacterial flora found in the nasopharynx of apparently healthy rams to see what could potentially influence the risk of bronchopneumonia.
Fifty-six lungs with signs of pneumonia and four healthy lungs were collected from two abattoirs in Rogaland from September to January 2020-2021. The lungs were photographed, investigated macroscopically and histologically, and samples for microbiological investigation were taken. Bacterial cultures and polymerase chain reaction were used to detect the presence of the three bacteria species of interest. Bronchopneumonia was macroscopically set as the diagnosis in 57.1% of the examined lungs, and it was observed that almost all lungs with macroscopically consolidated tissue were microscopically diagnosed as bronchopneumonia, pleuropneumonia or eosinophilic pneumonia. The prevalence of M. ovipneumoniae, M. haemolytica and B. trehalosi was not successfully described through PCR, but M. haemolytica was successfully cultured from 42.4% of the lungs with cranioventral consolidated tissue at macroscopical examination.
Fifty-four nasal swabs were collected from apparently healthy rams from different farms in Rogaland over one week during autumn 2020 and another swab in January 2021. Bacterial cultures were made, and 16S rRNA PCR performed in order to identify the colonies by Sanger sequencing. The most prevalent bacteria species was Staphylococcus sp. (47.8%), followed by Moraxella sp. (17.4%), Bacillus altitudinis (8.69%), and Paenibacillus sp. (8.69%). Other bacteria species detected were Shigella sonnei, Salmonella enterica subsp. diarizonae, Aerococcus viridans, and Escherichia coli. | |