The Sunday News
Farming Issues
DYSTOCIA is simply defined as the difficult calving experienced by cows or heifers. Dystocia can result in losses for both the dam and the calf. This can be traumatic to the farmer. This week, we look at some of the ways which farmers can use to manage dystocia. Dystocia management must begin with proper heifer selection for your breeding stock.
Breeding heifer selection should look at the conformation of the heifer itself and its lineage where records can be obtained.
When inspecting the conformation of the heifer, the farmer should look at the pelvic area of the heifer. This should be wide. A heifer with a narrow pelvic area is predisposed to dystocia when calving down. Another factor which contributes to dystocia is calf birth weight. The weight of the calf is a function of genetic and environmental factors. Genetic factors include sex, length of gestation, breed and heterosis, Non-genetic factors include age of the dam and nutrition of the dam during various phases of gestation. Efforts to manage the dystocia rate and moderate its effects should focus on replacement heifer development, sire selection, and early dystocia intervention.
Replacement Heifer
Dystocia is more likely to occur in heifers that are already breeding. This is why it is important for the farmer to take time when selecting his/her breeding heifers and to cull off those that are suspect candidates for dystocia. However it should be noted that some cows may also experience dystocia as a result of a number of factors which include the breed of the bull that serviced her.
Pelvic area measurements before the breeding season or at the time of pregnancy examination have been used to estimate the pelvic area before calving. Those heifers with a small pelvic area before the breeding season may then be culled or selectively mated to easy calving bulls, and those with a small pelvic area at the time of pregnancy examination may be identified for careful observation at calving.
Sire Selection
While other non-genetic factors such as birth weight, age of the dam and environment may cause or contribute to dystocia, careful selection of the sire can significantly reduce indecencies of dystocia in your herd. Some studies have suggested that cows that previously experienced dystocia are more likely to do so again. Some breeds of bull tend to cause dystocia in heifers and cows especially if they are mated with different breeds. One such breed is the beef master. If your heifers are serviced by a beef master bull and they are of a different breed, you are likely to record dystocia cases in your herd.
The incidences will also increase if your breed is of small frame. It is therefore prudent to use easy calving bulls for heifers. An example of an easy calving bull is the Brahman bull. A calf from the Brahman bull has a small birth weight as compared to beef master calves. As the birth weight of the calf increases, the incidence of dystocia also increases. Calving difficulty is higher for male than female calves. Abnormal presentations of the calf also accounts for most dystocia cases. This when a calf presents itself with such positions as folded legs and twisted heads making the parturition process very difficult.
Early Intervention
This is the most important part of dystocia management in your herd. Despite the best efforts to avoid dystocia, some cases will be seen. Early intervention minimises the effects of dystocia on calves and the dam. Heifers should be monitored regularly and provided with assistance promptly where labour is prolonged, say for an hour. A general rule of thumb is that if a heifer has not made significant progress in delivering her calf within 30 minutes, it is time to get help. It is important for your stockman to receive basic training in handling dystocia cases so that they can provide assistance in less complicated cases.
A veterinary officer should be brought in immediately if accessible. It is also important to always keep materials that are needed for assisting a dystocia case, such as soap, gloves and ropes. These will certainly become handy when you call for help.
