Whether scarce or plentiful, summer and autumn grazing’s nutritional value can be deceptive. This is rather more than just a question of quantity and can have a serious bearing on suckler cow fertility, calf growth rates and post-weaning recovery of ewes ready for breeding, according to vet Dr Elizabeth Berry from Animax.
“Perhaps surprisingly, human intuition plays an important part in misjudging things,” she explains. “We all know that ruminants have evolved to eat grass. So it’s not surprising if we add two and two to get five by assuming that pasture can supply all nutrients needed for high performance in cattle or sheep.
“Even if it’s plentiful and supplying all the energy and protein needed, most grazing in Ireland is deficient in one or more trace elements. Their essential roles in metabolic processes mean that shortages will limit all ruminants’ ability to utilise nutrients in grazed grass fully. In much of Ireland, the deficient trace elements are cobalt, iodine and selenium.”
Cobalt is needed by rumen bugs for producing vitamin B12, an essential component in energy metabolism and producing red blood cells. Iodine regulates metabolism and conversion of food into energy, while selenium is needed for enzyme synthesis and plays a crucial part in immune function and fertility.
Where copper is also deficient, most farmers already know about it from past bad experience. But for the most part, Dr Berry says it’s understandable if shortages of the other three go unnoticed if those looking after cattle or sheep get used to a certain level of performance as the norm. To test this invisibility, one ingenious beef farmer deliberately didn’t treat one animal in a group when giving Tracesure Cattle with Copper trace element boluses. Just two months later, the visible difference was obvious (see photo).
Of course, Dr Berry acknowledges that cattle with shiny coats don’t pay any bills in themselves. “But generally they are a reliable sign of good health, performance and potential profit,” she points out. “Perhaps 75 calves per 100 cows each year, a calf taking 18 months from birth to 450kg liveweight, or 1.5 lambs per ewe have become acceptable,” she suggests. “However, each of these is only modest performance. Financially, the difference between these figures and 90 calves, 14 months or 180% is massive. On some farms, addressing unseen trace element deficiencies can make the difference.”
Managing director of Veterinary Supplies, Roscommon Colm Tully adds, “clearly, sub-optimal function in any of the biological processes affected by deficiencies will have an adverse effect on animal productivity and financial performance. Addressing this before it happens is good business as well as affordable and easy to do.”
Trace element boluses relevant to this article are Tracesure Cattle with Copper, Tracesure Calf with Copper and Tracesure Sheep. These boluses have a slow-release ‘leaching’ mechanism developed and patented by Animax, not available from any other sources. The principles outlined here also apply to dairy herds including replacement heifer rearing.
Farmers can get more information from Animax livestock specialists here.