Tests done in a South African (SA) laboratory indicate no single cause for the recent mysterious livestock abortions that hit Namibia, especially the Khomas Region.
But they traced a mineral imbalance in most of the animals with some also indicating secondary bacterial infections. There was however no single consistent mineral abnormality and this would be expected as these outbreaks are being experienced in different geographical locations, where environmental conditions vary.
The outbreak originated in the Windhoek areas and then spread to the Omaheke and Otjizondjupa regions with devastating effects for some farmers.
For Dr Jolandie van der Westhuizen and Dr Anselm Voigts, who took the lead in the investigation, the most important points that became clear from this investigation were the following:
– Routine evaluation of liver samples from any animals submitted for slaughter is an important monitoring tool to reduce the risks of micronutrient imbalances.
– It is important that all supplements provided are balanced and meet the recommended requirements from a micronutrient perspective. Give injectable micro-minerals according to manufactures’ recommendations. Mostly before breeding, before calving and before weaning.
– The infection is of secondary nature and is a consequence of fetal immunosuppression. It is advisable that farmers use the knowledge and experience of private veterinarians and nutritionists in a holistic herd health approach to prevent diseases and increase production.
The independent tests were made possible by the Livestock Producers Organisation (LPO), the Namibian Agricultural Union (NAU), Feedmaster and the Meat Board of Namibia (MBN). A special committee comprising of government and private veterinarians was appointed with the primary objective to lead the outbreak investigations and come up with measures aimed at preventing the spread of the outbreak and getting better insight in the causing agent.
The deadly virus – expected to be of an unknown strand – has also resulted in veterinarians and officials now visiting selected farms with the sole purpose of getting more information about this outbreak, and urgently seek measures to halt the killer in its tracks.
The unprecedented flood of abortions are causing cattle losses of up to 85 percent in the central and eastern areas of Khomas as well as in Omaheke and Otjozondjupa regions.
Losses due to abortion ranged between 40 and 85 percent in the areas hardest hit. Although most of the abortions that were reported have taken place between 3-6 months, there were also reports of older calves aborted.