Beef cattle farmers will be able to fine-tune their selection and breeding programmes even further thanks to the research efforts of veterinarian Dr Dietmar Holm of the University of Pretoria. He has introduced the use of ultrasound and new criteria to measure the pelvis area of heifers to optimise pre-breeding examination systems.
His research is likely to have a significant impact on the beef cattle breeding industry by adding value to selection programmes and improving productivity of beef cattle operations. Dr Holm recently received his doctoral degree in veterinary science from the University of Pretoria. His findings take into account observations he made over the course of seven years of a Bovelder herd at Johannesburg Water’s Northern Farm. Some of the results have already been published in the international Journal of Animal Science.
Dr Holm has shown that heifers with relatively low reproductive potential in seasonal breeding systems can be identified before the first breeding season and before reproductive failure occurs. This means that animals with inferior potential can be removed to optimise productivity of a farm. His methods also help to prevent calving difficulties, without changing the frame size of the cattle herd.
“The cost effectiveness of synchronisation programmes for individual animals within a herd can be improved by doing ultrasound examinations of heifers’ reproductive tracts and pelvis areas, or by using reproductive tract scoring by rectal palpation,” says Dr Holm, who believes that measurements of the internal pelvic area are especially important to prevent dystocia or obstructed labour. “When ultrasonography is not available, the accuracy of reproductive tract scoring by transrectal palpation can be improved by repeating it in low scoring animals after seven days.”
Dr Holm says that reproductive tract scoring as a culling tool to predict heifer fertility compares well with other traits that are commonly used for heifer selection, such as Kleiber ratio. It is therefore useful as a pre-breeding examination method to identify beef cows with lower potential to reproduce successfully over the long term in a restricted breeding system. According to Dr Holm his research confirms the fact that reproductive traits have more impact on production in beef cattle than growth traits.
Dr Holm, who lectures in veterinary reproduction in UP’s Faculty of Veterinary Science at Onderstepoort, says he is already applying the outcomes of these studies through consultations with veterinarians who collect heifer pre-breeding data from beef clients. Ultimately, he hopes these formulas will help improve selection tools that are part of the computer models of SA Studbook and Breedplan, the two major service providers to the cattle breeding industry.
Dr Holm qualified as veterinarian at the University of Pretoria in 1998. After spending five years in private practice, he returned to Onderstepoort in 2003 for an academic career in production animals and obtained the degree MSc in Veterinary Science cum laude in 2006. He has published eight peer-reviewed scientific papers and presented more than 20 scientific papers at local and international congresses. He is actively involved in the veterinary community, where he is currently the chairman of the Livestock Health and Production Group of the South African Veterinary Association.