The summer of 2013 was excellent with record temperatures and limited rainfall of which was great relief for farmers conserving their winter forage requirements. The overall quality of all forage in Ireland has been of superb quality and it is unlikely that underfeeding or malnutrition will be a problem.
However, it is important to note that ewes will require supplementary feeding in the last third week of pregnancy. Additional energy must beprovided to avoid health and metabolic disorders and crucially to meet the demand of the growing foetus. In the last 7 weeks of pregnancy 75% of foetal growth occurs. Where ewes are not able to consume sufficient amounts of nutrients, to meet the demand of unborn lambs, there can be serious consequences. Ewes that are underfed in late pregnancy will have undersized lambs and less colostrum of which will lead to weak lambs leading to higher mortality. Also ewes will have less milk in early lactation leading to poor growth rates and at worst ewes may die from twin-lambing disease.
In order to avoid metabolic problems and poor lamb performance, the nutritional requirements of the ewe must be stepped up in the last few weeks of pregnancy. Energy, protein, mineral and vitamin supplementation must be introduced at this stage. Energy is the most important part of a ewe’s diet. It is important to check the energy supplied in the ration that you are purchasing.
Energy is measured in UFL’s (Unité Fourragère Lait) one UFL is the equivalent of one kg of air dry barley. Ideally ewes in late pregnancy should be offered a ration with a UFL value of 0.95. It is important to ask what type of ingredients is in your ewe ration. Ideally there should be feed ingredients of high energy content such as wheat, barley, oats, maize and high protein sources such as soya or maize distillers.
The protein requirements of the pregnant ewe are very important especially in the last three weeks of pregnancy. From mid pregnancy and up to the last three weeks of pregnancy each ewe will require between 100-130 grams of protein per day. The protein requirements will almost double in the last three weeks before lambing. For the last three weeks of pregnancy the ewe’s protein requirement will rise to 200 grams per day to meet the demands of the growing foetus. Naturally the ewe’s ability to eat forage will have declined and supplementation will be required. It is important to note, that double bearing ewes will require about 30% more feed compared to single bearing ewes. Ewes should have adequate feeding space, lying area and access to fresh water.
Mineral and vitamin supplementation will also be required for the pregnant ewe, particularly in late pregnancy. A free choice mineral mix will be required with all major minerals and vitamins supplied. In particular, Selenium and vitamin E are critical nutrients in late pregnancy, as low levels have been associated with poor reproductive performance and retained placentas.
The requirement of Calcium (Ca) almost doubles in late pregnancy. Consequently it is important to make sure that adequate Calcium is supplied to avoid milk fever.
In summary, energy is very important for the pregnant ewe particularly in last few weeks of pregnancy. Supplementary feeding must commence in the last few weeks of pregnancy. A form of concentrate or a ration will suffice paying particular attention to the declaration of feed ingredients, energy, protein, mineral and vitamin content.