The busiest period on Irish sheep farms is just around the corner, and according to the AHDB’s Reducing lamb losses for Better Returns report, health planning plays a crucial role in reducing lamb losses.
Here are six key illnesses that sheep farmers should look out for in their ewes in late pregnancy and during the lambing period.
1. Prolapse
Prolapse is a major cause of ewe deaths at lambing time, according to the AHDB.
Ewes carrying multiple litters are more likely to prolapse, it says, while overfeeding in late pregnancy is another contributing factor.
It recommends that farmers watch their ewes closely for any signs of prolapse, as it is essential to intervene at the earliest possible time.
The AHDB advises farmers to use a restraining harness to resolve this problem, or, if possible, they should seek veterinary treatment for affected ewes.
2. Pregnancy toxaemia (Twin lamb disease)
Pregnancy toxaemia or twin lamb disease is a metabolic disorder that occurs in the last four-to-six weeks of pregnancy, it says.
It can affect any ewe, but those with a high or low body condition score or carrying multiples are most are risk.
The AHDB says that, it occurs due to a lack of energy intake and decreased blood glucose levels in the final few weeks prior to lambing.
It also says that an affected ewe can be easily identified, as she isolates herself, looks dull, will not eat, appears blind and lies down.
For treatment, it recommends giving the ewe glucose as soon as she goes off her food, as this will give the best chance of survival for both the ewe and the lambs.
3. Hypocalcaemia
Hypocalcaemia is a metabolic disorder that normally occurs in the last four weeks of pregnancy due to the lamb’s demand for calcium being greater than the diet provided to the ewe, the AHDB says.
It advises farmers to look out for ewes that are unsteady, lie down and gradually enter a comatose state and die.
Affected ewes should be treated with a calcium injection (50-80ml) administered under the skin, it says, and if the treatment is successful the ewe should look brighter within an hour.
4. Mastitis
Acute mastitis in ewes is rare and is usually seen in the first weeks after lambing, the AHBD guide says.
Ewes suffering from mastitis may stop her lambs from sucking as her udder will become hot, swollen and painful.
These ewes may not have milk in the affected half of the udder, it says, but instead they may produce a watery liquid which contains blood or pus.
The amount of milk available to the lambs is also significantly reduced, the AHDB’s report says.
However, most cases of mastitis are sub-clinical and are carried over from the previous lambing, or chronic lambing which occurs at weaning, it says.
When sub-clinical mastitis occurs, the ewe may not look ill but her overall milk yield will be reduced, it says.
5. Metritis
Metritis is an infection in the uterus caused by an infectious abortion or an unhygienic assisted lambing, the AHDB says.
Ewes suffering from metritis will look depressed, will not eat, or show interest in her lambs and she will often have a swollen vulva.
The report also suggests that affected ewes will require antibiotics and anti-inflammatory treatment.
6. Listeriosis
Listeriosis is most common when ewes are fed silage in late pregnancy, as during this time the ewes immune system is less effective, according to the AHDB.
The bacteria which cause listeriosis are found in soil and it is incorporated into silage when grass is cut too low.
Farmers should keep an eye out for ewes that look dull, show slight paralysis and walk in a circle.
It also says that veterinary treatment with intra-venous antibiotics will work if it is caught early, but if the infection progesses to far, treatment often does not work.