At this time almost all spring-calving cows are weaned and, following the recent adverse weather, are probably housed.
This period in the annual cycle tends to get neglected but is probably the most important. The primary focus now should be to manage the body condition of the cow with correct feeding.
Generally, dry cows weigh 575-700kg liveweight, which gives the cow an energy requirement of 75mj/kg of dry matter and a protein content of 8.5pc. Most cows at this stage will have a body condition score of 3-3.5 and it is vital not to build on this condition score during the dry period. If the cows exceed condition score 3.5, it would be preferable to reduce this safely before calving.
The nutritional management of the dry cow will have a significant effect on the calf's health, the cow's post-calving health, fertility, the growth rate of the calf and ultimate weaning weight. Managing the feeding of the cow rather than just feeding for convenience will therefore pay off for the full year ahead.
This needs to be simple and also meet the cow's requirements. Most grass silage is of 9.5-10 metabolisable energy (ME), so when fed to appetite it will in most cases supply excess energy and protein and therefore increase body condition.
Fulfiling the appetite of the cow without over-feeding is difficult where cows are housed and have restricted feed space. Some suggest feeding the cows a number of times a day to avoid bullying and control body condition. However, I believe this solution is impractical, labour intensive and creates lots of stress on the cows.
When straw is included in the diet of the dry cow, it has a tremendous 'fill factor' for the cow. As most straw is low in energy and protein, and is fibrous, it will fill the rumen and reduce the appetite of the cow. Chopping and mixing with silage is the ideal method of feeding straw.
The amount of feed per cow is directly related to the quality of the forage/silage being fed. If silage of 10ME is fed, then up to 6kg /hd/day of straw will be required. This will mean as little as 25kg of silage per head is required to meet the nutritional requirements of the dry cow.
The choice of straw used may be limited at this time of year but the preferred option when chopping, and mixing is practised, is rape straw, if available. Wheaten straw is probably the most available straw and can be fed from round or square bales.
If the cows are in a bedded house, then it's best to feed the straw from a round feeder if chopping and mixing isn't an option. Cows housed on slats can carry a lot of straw into the pens while feeding, which will be wasteful and cause blocking of the slats. In this situation, the best practice is to first roll out the straw and then cover with silage to reduce the straw wastage.
Make sure that a good quality mineral/trace element/vitamin supplement is supplied to all dry cows for the full dry-cow period. Special attention should be paid to ensuring that there is no calcium contained in the supplement and there is an adequate supply of magnesium (minimum 15pc) to avoid 'downer cows'. Silages with high levels of potassium may require much higher levels of magnesium than is in a standard dry-cow mineral.
Gerry Giggins is a nutritionist with Richard Keenan and Co. Email: firstname.lastname@example.org Phone: 087 906 6478