Onus on ewe to bridge nutrition gap
Published 02/03/2010 | 05:00
Grass growth has been at a virtual standstill since before last Christmas. In fact, on fields that were closed very early (late September or early October) the grass is more than likely decaying and therefore yield is actually dropping.
Experience from some sheep farms that have been measuring grass for the past few years would suggest that farm covers in February were about half of what they were last year, with little hope of the situation improving before the onset of lambing and turnout.
There are a number of issues that sheep farmers will have to deal with in the coming weeks to get their sheep fed and facilitate grass to grow when warmer weather arrives.
The most important task is to ensure that the ewes are fed adequately. When the ewes are first turned out, they will selectively graze out the better, greener and leafier material which will be of a higher food value.
However, in order to allow light to the base of the sward and to stimulate tillering, the brown-type grass will also have to be grazed off. During the period that the ewes are grazing off this grass their energy and protein intakes will be substantially reduced.
Good quality spring grass contains around 21pc crude protein and generally has an energy value of around 1.06 UFL/kg dry matter. A ewe rearing two lambs will have an intake of about 2.4kg DM/day.
Her requirements for the first six weeks post-lambing are 2.5 UFLs plus 400g of crude protein. In a normal year unsupplemented spring grass will supply her with adequate energy and protein.
However, the type of stuff that most ewes will be forced to eat this year is probably in the region of 0.85 UFL and 13-15pc crude protein and, given the lower digestibility, it is likely that intake will also be somewhat depressed.