In lamb hoggets

The harsh winter is giving rise to reports of in-lamb yearling hoggets varying significantly in condition. There is little point in overfeeding hoggets in late pregnancy, as this will only give rise to greater lambing difficulties. Instead, the diet offered should be targeted to nutritional demand and follow a similar pattern to ewes in late pregnancy or a flat-rate feeding regime. These animals will require preferential treatment in early lactation to ensure they get back on track as soon as possible. Single-suckling hoggets in good condition will generally perform satisfactorily on good-quality grass, but where condition is lacking hoggets will benefit from 300g to 500g of concentrates.

Some farmers get by okay by grazing twin-suckling hoggets on good-quality grass, but the general recommendation is to treat these animals like mature ewes rearing triplets. This includes offering 0.5kg concentrate supplementation with good-quality grass for the first five to six weeks of lactation and offering lambs access to creep feed. Feeding levels offered to hoggets will need to increase where grass quality or quantity is limiting, while where hoggets are likely to face significant difficulties in rearing twin lambs, then the best option may be to remove one lamb for artificial rearing.

Tetany risk

The forecast dip in temperatures is likely to create more challenges during the lambing season. There is likely to be a higher risk of grass tetany in ewes that are under stress, or where animals are turned into fresh, lush pasture. Swards with a high nitrogen (N) and potassium (K) level are the main offenders due to low magnesium levels. Animals have a poor capacity to store magnesium and must ingest sufficient levels on a daily basis to prevent a deficiency occurring. The level of magnesium absorbed from forage is depressed by high N and K levels in the sward, as mentioned above, rapidly growing swards and rapid transfer of leafy grass through the animal.

The disease presents the highest risk when the above conditions combine with any factors that put an animal’s system under stress. These include a nutritional intake deficit (risk higher where suckling multiple lambs), sudden changes to the animal’s diet, difficult weather or any other significant stress factor. Prevention centres on ensuring animals achieve their required daily intake. There are numerous options from offering ewes high-mag lick buckets, concentrates containing magnesium, boluses or adding magnesium to water. Supplementation should be introduced two to three days in advance of the high-risk period.

Orf vaccine

The orf vaccine is a useful way of helping to reduce issues in flocks with a history of the disease. It should not be used in clean flocks, as doing so will only serve to introduce orf into the flock. There is no cure for the disease, with the virus needing to run its course. Where there are significant lesions present antibiotic treatment will help to prevent secondary infection. In some cases, lambs can contract the disease on the inside of their lips, which restricts suckling. Such lambs may need to be removed or ewes brought indoors so lambs can be artificially fed. Be careful where handling animals with the disease as it can also be contracted by humans.