Beef and sheep notes April 2009

How tight has your calving pattern been so far this year? How many cows are there left to calf in the month of April or even into May? It is now well recognised that compact calving leads to less work on a suckler farm and contributes a lot towards the profitability of a suckler herd through:

• Less mortality at calving

• Higher average weaning weights

• Healthier weanlings

• More even weights of cattle for sale (right up to finishing)

Calves born in April and May are lighter at weaning because they are younger and don’t consume much grass before autumn. These calves tend to have poor daily gains from birth to weaning compared to the earlier born calves. The first target should be to have all of your cows calved within an eleven week period. The second target should be to have 65 percent of the cows calving calved within the first three weeks, and the third target is to have a further 20 percent calved in the next three weeks. For a lot of farms this might seem to be too extreme, but working towards it gradually will pay dividends. Cow condition at mating is crucial to achieving these targets. Cows which lose excessive body condition after calving will be much slower to return to breeding. The importance of sufficient early spring grass for grazing is essential. First calvers are likely to lose more body condition than mature cows and are slower to recover weight at grass. Giving these animals preferential treatment from the main herd at this time of year could be beneficial in minimising weight loss.

The bull also needs to be in good shape for the breeding season - fit but not fat. Treat hoof problems well in advance of turnout. Young bulls reared on high meal diets need to be gradually reduced to about 2-3kg meal per day. For a start, young bulls should mate 3 to 4 cows before letting them run with the full herd. It is important to keep a close lookout for repeats, especially at the start of the season. It is estimated that 4 percent of bulls are completely infertile and up to 20 percent are partially or periodically infertile. Take the dates of first matings and check at 18 to 23 days later for repeats. Young bulls should be confined to about 20 cows in their first season while older bulls could cover about 40 cows.

Get your bull ready for the breeding season

As livestock are turned out, one major concern for farmers will be the prevention of Grass  tetany (‘Staggers’). The risk of tetany increases where animals are under stress as a result of unpredictable weather and change in diet at this time of year. The immediate cause of Grass Tetany is a low level of blood magnesium (hypomagnesaemia) and most farmers are all too familiar with the symptoms of staggering or convulsions.

Early grass is the key on many sheep farms to achieving good growth rates in lambs. Good grassland management and utilisation are also essential to ensure that growth rates continue into summer.

Early applications of slurry and Nitrogen will have stimulated grass growth. Targeting younger swards gives the best response. Maintain sward height between 6 – 8cms during April and May. Provide lambs with the best grass - forward creep grazing is a modification of paddock grazing where the un-weaned lambs graze one paddock ahead of the ewes. The paddocks where the lambs graze always have fresh grass with less chance of parasite infection. Many sheep farmers in Northern Ireland could achieve this by purchasing inexpensive creep gates.

A good grass clover sward will increase lamb growth rates by around 20 percent. White clover in the sward improves the protein content and has a higher level of minerals coupled with higher digestibility levels. Grass clover swards also provide considerable fertilizer savings