SCOTTISH farmers are increasingly calving their beef cows at this time of year, partly because spring-calving cows don't have calves suckling them during the winter months and as a result are cheaper to feed. Autumn calving cows on the other hand have to produce milk for the calves they are still nursing during the winter and need a more nutritious and expensive diet.

Another advantage of calving in late February and March is that the calves have grown big enough by May to benefit from the flush of milk their mothers produce when they are turned out to nutritious spring grass. The end result of such a strategy is that "suckled" calves born at this time of year are well-grown at weaning in October and are much cheaper to produce than autumn-born calves.

Just because spring-calving beef cows can be fed a cheaper, forage-based diet, doesn't mean that you can get away with not feeding them properly. They need to be neither too fat nor too thin. Fat cows often have difficulty giving birth, as they don't push their calves out as quickly as trimmer ones and may also have bigger calves that need to be assisted at birth. Lean ones tend to have smaller calves, but may not give enough milk - or more importantly not have enough good-quality colostrum to get their newborn calf off to a good start in life.

Colostrum is a thick milk produced for a couple of days after calving that acts as a laxative for the calf and passes on immunity to a host of diseases that its mother has encountered during her life - but it must be suckled within a few hours of birth to be effective. Colostrum quality relies on a healthy mother with an active immune system and adequate protein quality in the diet.

Some boost the rations of their cows with a mineral supplement containing additional magnesium about two to three weeks before they are due to calve. The extra magnesium helps mobilise the cow's own body reserves of calcium, improving muscle tone in the womb and helping to prevent prolonged calving.

Predicting difficulties at calving is not a precise science and is often linked to both the physiology of the cow and its calf. For instance, a small cow with a large pelvis will often have an easier time at calving than a large cow with a relatively small pelvis. Then again, a modest sized calf with thick shoulders or a beefy, double-muscled backside may not slip out as easily as a large, narrow calf.

There may also be difficulties caused by the calf coming backwards, or in a breach presentation where its bottom comes first with its hind legs tucked under its body, or with one or both of its front legs pointing backwards in the birth canal - to name but a few of the problems that can occur.

The main sheds where I kept my beef cows all lay within a couple of hundred feet of the farmhouse. As beef cows have a tendency to calve during the night, I used to sleep with my bedroom window open at calving time so that I could hear the distinctive moaning sounds of a cow going into labour. Then it was a case of getting up regularly through the night to keep an eye on things.

I can tell you that there is no more gut-wrenching sight than a big pair of hooves protruding from the back-end of a cow, indicating a big calf that needs assistance to be born.

When examining a cow the first thing is to establish how the calf is being presented in the birth canal and if it is still alive. When you reach in with your hand a live calf often jerks its foot when you handle its legs or pinch the skin between its toes. You can also stick a finger in its mouth to see if it sucks or gags.

More importantly, if there is no muscle tone and the anal sphincter is completely flaccid then the calf is dead.

Acting as a midwife to a big beef cow is heavy work, not as hygienic as in an NHS maternity ward, and invariably the farmer needs to take a shower afterwards.

This can be a stressful and sleepless time for beef farmers.