CASE NOTES
COLIFORM BACTERAEMIA, WITH MENINGITIS AND OTHER SEQUELAE, IN A NEONATAL BEEF CALF
Ian Poe District Veterinarian, Kempsey
Posted Flock & Herd December 2016
Introduction
Bacterial meningitis is reported as an uncommon sequel to bacteraemia in neonatal calves (Parkinson et al. 2010).
CASE REPORT/SERIES
A local beef producer contacted the District Veterinarian (Kempsey) to investigate the cause of death in a 2 day old Droughtmaster cross bull calf. The mob of 35 cows was grazing improved tropical pasture, mainly kikuyu, paspalum and clover. The calf in question was noted to initially have a depressed appearance and difficulty standing, later it began to display opisthotonus before becoming recumbent and dying.
Necropsy findings
Externally there was a thick white/yellow material noted in the anterior chamber of the left eye (Figure 1). There was an increased amount of straw-coloured fluid in several joints. The abdomen contained numerous strands of thick yellow material (Figure 2). The brain appeared hyperaemic, there was opacity of the meninges and the gyri appeared flattened (Figure 3). There was no milk-clot present within the abomasum.
Fresh and fixed brain, pericardial fluid, joint fluid and hair were collected and submitted to the laboratory.
Figure 1. Photograph of hypopyon observed in the post-mortem calf.
Figure 2. Photograph of fibrin clots observed within the abdominal cavity of the post-mortem calf.
Figure 3. Photograph of the brain from the post-mortem calf displaying hyperaemia, meningeal opacity and flattened appearance of the gyri.
Laboratory Findings
Histopathology of the brain revealed severe multifocal, acute, fibrinosupurative meningitis with vasculitis, fibrin thrombi and bacteria. Escherichia coli, in a profuse predominant growth was isolated from routine culture of the brain.
Bovine viral diarrhea testing was negative for both antibody and antigen.
Discussion
Meningitis in calves most commonly occurs in calves less than 2 weeks of age and has been reported in calves less than 24 hours old. The onset of clinical signs of meningitis in neonatal calves is usually sudden (Parkinson et al. 2010). Meninigitis may be accompanied in calves by polysynovitis, endocarditis and hypopyon (Radostits et al. 2000). In the live calf, examination of the CSF is the only means of obtaining a definitive diagnosis.
Response to treatment in affected animals is likely to be poor so attention should be focused on prevention through management activities which promote passive transfer of immunity and reducing the risk of bacteraemia by ensuring prompt, effective diagnosis and treatment of infectious conditions such as omphalophlebitis and enteritis (Parkinson et al. 2010).
References
- Radostits OM, Gay CC, Blood D and Hinchcliff KW.Veterinary Medicine9thEdition Saunders, London. 2000
- Parkinson T, Vermunt JJ, Malmo J. (2010)Diseases of cattle in AustralasiaNew Zealand Veterinary Association Foundation