Preparing the Suckler Cow for Autumn Calving
Preparation of the suckler cow for autumn calving is based around having her at optimum health and body condition score. Feeding suckler cows is based on a fairly simple principle – namely, feed to body condition score in relation to the stage of the production cycle.
There are ideal body condition scores to aim at during the various stages throughout the year. Body condition scoring involves regular assessment of individual cows and calculation of the herd average.
The herd body condition scores for autumn calvers should move in the range of 2.0 to 3.0. Having cows much above condition score 3.0 is wasteful and increases calving difficulty if they are over-fat at calving. However, the bigger loss occurs with cows that are under 2.0 at calving or mating.
Teagasc research shows that cows that are under 2.0 at calving will be up to three weeks slower going back in calf. Also, where there are a significant number of cows in a herd under 2.0 at calving, the calving interval will not be maintained at close to the 365 day target.
Ideally, autumn calvers should be at, or somewhat above condition score 3.0 at calving and should not lose more than 0.5 of a condition score up to mating. Once the cow is settled in calf, a further 0.5 condition score can be lost with no adverse effect on production or fertility.
The feed requirement of autumn calvers depends on condition score at calving and the level of milk production. Recommendations would be to feed the suckler cows that are at the optimum body condition score ad-libitum grass silage at a preferable DMD of 70-72% during the dry period and post-partum.
If the cow is at body condition score 2.0 at calving, she cannot afford to lose any condition up to mating and should be offered ad-libitum grass silage at a preferable DMD of 70-72% – together with an additional source of protein and energy.
A straight feed ingredient such as soya hulls, beet pulp or citrus can be offered. Sometimes it may be best to keep it simple and feed a balanced form of
concentrate, or a coarse ration at 3 kg per head per day to increase the body condition of cows after calving.
The grass silage quality together with the body condition score and potential milk yield of the suckler will dictate the amount of additional feeds required to allow it to get back into positive energy balance following parturition.
In energy terms, a 600 kg cow requires 5.5 UFL units of energy for maintenance. The feed requirement of a suckler cow giving five litres of milk is approximately 45 kg of silage at 68% dry matter digestibility plus 1.0 kg of concentrates per day. A cow giving 10 litres of milk per day would need 3.0 kg meal with the 45 kg of silage to stay at the same body condition.
In practical terms, relatively good silage ad lib and 1–2kg meal per day up to mating should keep adequate condition of 3.0 on autumn calvers.
High quality silage has adequate protein for a suckler cow giving six-eight litres of milk. As digestibility falls, both energy and protein intake also falls. On lower quality silage, feed a 16% crude protein ration. Each five units drop in dry matter digestibility from 70 % requires an increase in the meal input of about 1.0 kg per day.
A post-calving mineral of about 100 grams per cow per day should be fed on the silage or as part of the concentrate ration.