5 Case Studies on Melioidosis and the non-fermenting gram-negative Bacteria
Case A: Melioidosis in goats
On a goat dairy farm in Townsville, every year from January to March a few of the nanny goats developed melioidosis and died. Different strains of Burkholderia pseudomallei were identified by genotyping.
Questions
- Provide possible reasons for the seasonal occurrence of melioidosis (epidemiology).
- What advice should you as veterinarian give to the farmer regarding the prevention of further cases?
Case B : Pink-eye in a dairy herd
It is summer, there has been periods of rain followed by very warm, dry weather. The 400-cow dairy herd you consult for on the Atherton Tablelands is experiencing high numbers of cattle with runny and red eyes, they are constantly in the shade and some of the eyes have gone cloudy. You examine the eyes of the more severely affected cows and note that some have corneal ulceration.
Questions
- How should the infectious cause/s of this disease be diagnosed and what are the most likely infectious causes (differential diagnosis)?
- An inactivated pink-eye vaccine (Cooper’s Piliguard) is available, but it is not effective. What are the possible reasons for this?
Case C : Endometritis in mares
A 10-year-old Warmblood mare is presented for a routine pre-breeding examination. During the assessment, a purulent vaginal discharge is observed. On vaginal examination, the discharge is noted to be originating from the cervix, suggesting uterine involvement. The breeding farm recently imported two mares from Ireland.
Questions
- What are the possible underlying reasons for the mare developing a suspected purulent endometritis?
- What are the more likely infectious agents involved in this case?
- What diagnostic tests should be carried out to determine the infectious cause?
Case D: Suspected ovine brucellosis in breeding rams
A Merino breeding operation in Victoria has recently come under new management. The owners have purchased several new rams and wish to join the Ovine Brucellosis Accreditation Scheme. As the consulting veterinarian, you visit the farm to examine all rams and note that several rams have enlarged epididymides, suggestive of epididymitis. Consider the implications for accreditation and flock fertility.
Questions
- What cytological evidence in semen would suggest the presence of Brucella ovis infection?
- How could this suspect diagnosis be confirmed.
- If confirmed what advice would you give to the new owners?