Michael Gottstein, Head of Sheep Knowledge Transfer, provided advice on grassland management, drafting early lambs and grass tetany control in the April edition of the Teagasc Sheep Advisory newsletter.
Nitrogen applications
When applying nitrogen (N), there are significant savings that can be made by spreading urea as opposed to CAN. To reduce both costs and emissions, the best option is to use protected urea to deliver the N component of chemical fertiliser applications.
Grouping up lambs
Grassland management is simplified and more grass is grown where the number of grazing groups are kept to a minimum. Keep this in mind when running several different groups of ewes and lambs. There is an advantage to grouping lambs according to age, as this simplifies flock health treatments such as nematodirus control, etc. However, there is little justification in keeping a number of different grazing groups of lambs that are similar ages.
Silage ground
Aim to fully graze out silage ground before closing up. This will remove all the old grass and facilitate new growth that will result in higher quality silage. Roll silage ground after closing to reduce the risk of contaminating the silage with soil during harvesting. If silage ground needs lime then it is best to delay the application until after silage has been harvested.
Grass tetany control
Grass tetany is a condition that affects lactating ewes and is frequently fatal. The condition is caused by magnesium deficiency. Magnesium is not stored in the body to any great extent; consequently, lactating ewes need to be supplemented with magnesium daily. Each lactating ewe requires about 1-2g of magnesium per day. During periods of stress and poor weather the absorption of magnesium is reduced, which is why we recommend daily supplementation rates of 3-5g per head per day. Giving ewes access to high magnesium mineral buckets (do not use buckets with high levels of copper) does the trick on most farms. However, there are also other options available to supplement magnesium, including meal feeding, pasture dusting and magnesium boluses. Supplementation magnesium in water is not effective, as ewes will drink very little water during wet weather.
Drafting early lambs
Monitor kill-out rates for early lamb production systems. Well fleshed lambs killed prior to weaning can yield 50% or greater; however, once weaned this will begin to drop. Weigh lambs prior to them leaving the farm and work out the kill-out percentage. This will allow you to adjust drafting weights for subsequent batches.
Source: EMM/ The Agriculture and Food Development Authority