Louise Hartley talks to Angus Wyse, the senior veterinary inspector at the Farmers Guardian-supported Builth Wells ram sale, to find out more.
Up to a third of all stock rams and bulls have reduced fertility and up to 10 per cent can be totally useless, according to recent survey.
However, Angus Wyse, of Castle House Vets, Newcastle Emlyn, Carmarthenshire, says by taking a few simple precautions and putting a bit of extra thought and effort into looking after stock males, the risk of significant problems can be considerably reduced.
A few simple questions when buying a new ram or bull can save many problems later, says Mr Wyse.
“The health status of the supplying premises needs to be investigated. In many instances, the only animals bought-in are new stock sires and they can introduce diseases which are not normally found on that farm.
“A BVD antigen test is easily arranged from a blood sample, and will avoid the potential disaster of introducing BVD virus into a clean herd.”
Many sales run by breed societies or livestock associations have a strict vetting practice before sales go ahead, ensuring some of the more obvious causes of infertility can be detected before purchase, he says.
“Most problems can be detected by a simple physical examination looking for abnormal lumps in the testes and feeling for mobility and tone in the testes.”
Some progressive breeders are semen testing stock before sales to ensure semen production is normal, says Mr Wyse, although unfortunately this gives no indication of the male’s ability to seek out females in season or serve them effectively.
Another problem can be overfeeding youngstock to achieve high growth rates and body condition before sale, he adds.
“It comes as a bit of a shock when these animals are turned out onto a bleak hillside with a flock or herd and expected to work.
“It is encouraging to see increasing numbers of producers rearing their stock under more commercial systems, and these rams and bulls are ready to go out and work in more challenging conditions.”
All too often the bull or ram is completely forgotten about until just before he is needed, says Mr Wyse.
“Semen production takes about three months and any illness which causes an increase in temperature during this time will lead to a reduction in fertility.
“Routine vaccination against the common diseases not only protects against mortality. It is also important to avoid any disease which can cause a significant increase in temperature, as this will affect future fertility.”
Rams, in particular, are susceptible to heat stress. Ensure they have access to shade over summer and any woolly scrotums are shorn early, advises Mr Wyse.
“Lameness can also be a major problem influencing infertility. Regular foot trimming of bulls and rams can improve their working lifespan and foot bathing is useful to control digital dermatitis or scald, a common problem in working bulls and rams,” he says.
“Leg and foot conformation are important as they affect the sire’s ability to walk and serve effectively.”
Once the bull or ram is sent out to serve, make sure they are working by conducting regular observations of the flock or herd.
“Marker harnesses or the use of raddle can give useful information to assess activity and effectiveness, and recording the marks will show if a high number of repeats are occurring.
“Rams and bulls can be an expensive investment. It is well worth taking a bit of time and effort to look after your stock males to ensure they produce the maximum number of progeny over a long and profitable life.”