Nick Garvey is a vet from Ballyshannon, Co Donegal, and he puts great emphasis on the benefit of implementing a prevention rather than cure approach to disease.

This is critical at lambing, because while the lambing period is one of the most rewarding times on a sheep farm, the high-stress nature increases the risk of disease becoming established. Indoor lambing systems are much more prone to outbreaks of disease due to the concentrated nature of the system.

The greatest risk is often towards the end of lambing due to a build-up of disease over the lambing period and farmers, in some cases, tending to take their eye off the ball as lambing nears an end.

Watery mouth

While early in the season, Nick says he has already dealt with cases of watery mouth this year. He says usually the first lambs to get struck by watery mouth are lambs from multiple births (double or triplet-born lambs). One reason these lambs are more susceptible to infection is because there is more competition for colostrum from the ewe compared with single-born lambs.

Colostrum is a key source of natural antibodies to disease and is vital in animals developing a solid immune system.

Garvey also finds sub-optimum husbandry conditions help the spread of the disease in a lambing flock. He says dirty lambing and individual pens, as well as ewes with faecal contamination on their wool, are a hotbed for disease caused by E. coli bacteria. If a lamb’s mouth/naval gets contaminated with dung or dirty bedding material before they take in colostrum, bacteria will build up in their intestine, causing illness and, in the majority of cases, death.

Lambs with watery mouth are often difficult to identify early on. In the initial stages of the disease, their intestine becomes overgrown with bacteria and a build-up of partially digested milk becomes trapped, which creates the illusion that their bellies are full. Nick says these lambs will frequently be lying in the corner of the pen with full bellies and most farmers who are busy lambing won’t notice they are sick until it is too late.

For treatment of sick lambs, Nick advises that oral rehydration and a laxative as soon as possible may help. Dead lambs should be sent to a veterinary laboratory for a cultured sensitivity test to assess what strain of bacteria is causing the fatalities, explaining that it is only then that a suitable antibiotic can be chosen to treat sick lambs.

Some farmers try to prevent lambs getting watery mouth by administering a Spectinomycin-based oral antibiotic shortly after birth. However, Garvey is slow to recommend this as a blanket approach as he feels antibiotic resistance is becoming a problem on some farms.

Hygiene

The best way to prevent watery mouth becoming a problem in your flock is to improve hygiene. Lambing pens should be maintained and well bedded with straw so faecal contamination doesn’t build up on ewes’ wool, especially around the udder region. Good parasite control in ewes and clipped tails will also help reduce contamination.

Individual lambing pen beds should be kept dry and clean, with pens cleaned regularly. Garvey advises not to skimp on straw. “You should be able to kneel on the bed without getting wet,” he says.

He added that some farmers are good at cleaning out pens regularly, but don’t re-bed with adequate levels of straw and lambs are lying on wet, contaminated surfaces full of diseases. Hydrated lime should also be used in conjunction with deep straw bedding, but Garvey warns that while hydrated lime will help, it is not a substitute for regular cleaning and adequate straw.

Colostrum

As mentioned, adequate colostrum intake straight after lambing is essential. Ewe colostrum is the best source as it will contain vital antibodies to fight infection (often specific to the farm) that the lamb will come into contact with.

Artificial colostrum can also be used, but Garvey advises farmers to ask their local vet which is the best one because some are of poor quality. He feels all weak lambs and lambs from multiple births should be stomach-tubed soon after birth with colostrum to make sure they get enough of the vital antibodies.

There is a vaccination available for watery mouth that can be given to the ewes one to two weeks before lambing. The vaccine is acquired through passive immunity, meaning vaccination will only be worthwhile as long as lambs are getting enough colostrum.

If colostrum yield in a high percentage of ewes is a problem, then there may be a need to look closer at the quality of the diet in late pregnancy. “If an outbreak occurs, farmers should concentrate on preventing lambs from picking up the disease and putting preventative measures in place rather than focusing solely on treating very sick lambs,” explained Garvey.

Joint ill or navel ill

Another common problem on some farms around lambing time is joint ill. It is also caused by a build-up of bacteria, but instead of building up in the intestine, it builds up in the knee, the hock or the fetlock of the lamb.

Garvey receives calls every year with cases of joint ill and finds it very frustrating to treat. Usually, cases can be identified by a swelling in the joint and the lamb will also generally have a significant limp and will be in pain. It can be identified in the navel by a swelling of the region and a hard feel.

Treatment generally involves a round of antibiotics, prescribed by the local vet, and pain control (anti-inflammatories) should be used. The reasons why lambs pick up joint ill are similar to watery mouth. Garvey says infected lambs either didn’t get enough colostrum at birth or the living environment wasn’t clean enough.

To prevent an outbreak, attention to detail when bedding and cleaning pens and getting adequate quantities of quality colostrum into lambs at birth is paramount. Garvey also advises to treat and dry the lambs naval soon after birth. He usually uses chlorhexidine solution over iodine. He feels iodine can be too concentrated at times and may cause chemical burns to the lamb’s naval and ewes are less attracted to chlorhexidine. Therefore, the ewe is less likely to damage the naval while licking the lamb. Garvey says when it comes to diseases at lambing time, “good husbandry will solve one problem and prevent others.”