Anthelmintic efficacy: This week’s focus on summer health tasks touches on the important role of faecal egg count testing in determining the need to administer worm treatments.
Faecal egg count reduction tests are a vital component in establishing the efficacy of anthelmintics and finding out if resistance is an issue on your farm.
Unfortunately, there are some flocks where there is now resistance to the three commonly used anthelmintic classes – benzimidazoles (white drenches), levamisole (yellow drenches) and macrocyclic lactones (clear group, eg ivermectin, moxidectin, doramectin).
In such instances, developing a treatment programme with your vet is vital to try to prolong the lifetime use of these products and also protect the only other anthelmintic class currently available, monepantel, which is the active ingredient in Zolvix.
Depending on the level of resistance, options can include dual treatment with products where there is known resistance, with this approach improving the efficacy over using one product individually. This strategy should be combined with strategic use of Zolvix at high-risk periods when the worm burden or threat of disease is at its highest level.
Key management practices to slow down the rate of resistance developing include alternating between active ingredients, avoiding unnecessary treatments and administering the correct volume of product for the weight of the animal. The latter is an area where faults are frequently identified at this time of year. If using a dosing or injection gun, it is important to check that it is delivering the correct volume. This should be repeated during the task if treating large numbers.
Lamb presentation: There is more talk in recent days surrounding the potential for exporting ram lambs live. The interest is mainly from buyers who have been handling fleshed cull ewes in recent months and it has helped to keep a good floor under the trade. Some have purchased small numbers and are hopeful of demand building towards the end of the month in advance of the Muslim festival of Eid al-Adha, which starts on 19 July. Demand has traditionally been for lowland ram lambs of continental breeding, possessing a good cover of flesh and ideally with tails. Where ram lambs are being traded in the mart, then it is advisable to batch suitable lambs.
Mart managers also report some batches of lambs being presented for purchase for slaughter and poorly matched on size, weight and flesh cover. Adding a couple of lambs to a group which are inferior to the others will in most cases end butcher or wholesale interest. While it will also put some factory agents off and should be avoided.
Grass management: Grass growth rates have taken off in the last week. The average across sheep farmers measuring and recording grass growth through Teagasc’s PastureBase Ireland facility is 81kg DM/ha per day, with a range from 55kg DM to 135kg DM.
At this level of growth, it is critical to stay on top of grassland management and keep good-quality grass ahead of lambs.
Strong paddocks should be taken out of the rotation quickly and lower-priority stock such as dry hoggets or ewes should be used to graze out paddocks after lambs. Continuing to apply even a small volume of nitrogen will help to maintain grass quality while maximising growth rates will help to replenish forage supplies after poor spring growth.