Beef and sheep notes March 2007

Spring calving suckler cows should have a body condition score of 2.5 - 3.0 approaching calving. Cows with a body condition score higher than 3.0  should be separated out from the main herd and placed on a restricted diet.  

Thin cows in poor body condition should be fed ad lib silage of at least moderate quality. If the silage quality is below average supplementing with 1.0 to 1.5 KG meal per day in the final weeks prior to calving may be necessary.  

Pay particular attention to first time calvers, older cows, the best milkers and shy feeders as these are likely to be thinner than the other cows in the herd.

Good hygiene in the calving area will reduce the incidence of E. coli mastitis which is a major cause of cow deaths shortly after calving.  Thoroughly clean and disinfect calving pens before the main calving period starts.  

While careful supervision is necessary at calving, it is equally important not to intervene too early in the calving process.  

More problems are likely to arise where intervention occurs too early than where the cow is left for two or three hours after the calf’s feet appear.  Although the calving jack is a useful tool it should only be used by experienced operators and must never be used to exert undue pressure.

Always consult your veterinary surgeon if there is any doubt that calving is not progressing normally.

The yield of silage can range from 30-45 tonnes/ha (12-18tonnes/ac) and this means that the cost of production can range from £11 to £16/tonne.

When an “opportunity cost” of using owned land or conacre prices ranging from £200-300/ha (£80-120/ac) is added, cost per tonne of silage increases by a further £5-£10/tonne.

Dry matter (DM), Metabolisable Energy (ME) and Crude protein (CP) content have a large effect on the feeding value of silage.  

Silages with differing analyses can be valued by comparing them to the feeding value and the current costs of barley (£135/t) and soya (£158/t).

The table below shows the relative value of poor, average and good silage.  This indicates that average silage (DM 24 percent, ME 10.6MJ/KGDM and C.P. 13 percent) below £31/t is better value for money than barley and soya with minerals.

It is impossible to put an accurate value on silage without having it analysed.

Value of poor, average and good silage relative to barley and soya.

Grazed grass is a much cheaper feed than conserved forage and this means that cattle should be turned out as soon as possible. Plan to turn cattle out to the driest fields. Lighter cattle should be turned out first and where possible separate into smaller groups over a larger area to keep stocking density low and reduce poaching.

Avoid waiting until there is a good build up of grass as the rate of growth at this stage will result in an oversupply of grass and subsequent reduction in grass quality in late spring and early summer.

For those ewes already lambed, high levels of quality feed are still required.

A ewe suckling twins has a very high energy requirement (approx. three times the maintenance level.) Meal feeding is not required if grass cover is at least 1800 KG DM /ha or approximately five cm for a dense sward. If grass supply is insufficient feed 1kg concentrate/day of a high quality energy and protein supplement to ewes suckling twins and 0.6 KG concentrate/day to ewes suckling single lambs.

The ewes’ resistance to worms drops significantly around parturition with a rapid increase in the worm burden within the ewe. If this is not treated at this stage the ewe will heavily infect grazing pastures with worm eggs resulting in high levels of

infection in lambs six to eight weeks later. Ewes need to be dosed with an effective anthelmintic (with high efficacy against worm eggs) around lambing time. Consult with your veterinary surgeon on effective worm treatment.

New reseeds and swards high in perennial ryegrass are likely to give the best response to early nitrogen. Remember it takes grass to grow grass so avoid overgrazing of fields where possible, as this will have subsequent effect on future grass growth.

Silage areas can be incorporated into the early grazing areas and sheep should be grazed at 7 – 10 ewes/hectare depending on grass covers.

Do not overgraze swards as it will take them longer to recover.

Good planning should ensure that sufficient grazing areas are available and that sheep can be moved to allow fresh re-growth.