Veterinary Ireland held an all- day conference on sheep health and diseases recently in Athlone. The conference was well attended with more than 100 vets from all over the country up-skilling themselves on all things ovine. It is a few years since such an event was held but, judging by the interest and feedback, this sort of conference will be held more frequently in the future.
One of the talks on lamb diseases was given by Prof Michael Doherty of UCD Veterinary College -- and was very interesting.
Prof Doherty spoke about lambs born with, or quickly developing, nervous signs. These include young lambs going blind or staggering around the pen in an unusual manner. Sometimes the signs are simply a lamb in poor condition and not interested in its environment. Others are more dramatic, with the head tilted to one side or even held backwards in an exaggerated upright position.
We group all of these under the heading of neurological diseases. Some of the diseases we are quite familiar with, such as meningitis caused by E-coli or Salmonella bacteria. E-coli will strike the vulnerable lamb at birth or in the first few days of life. It is an environmental disease in that it is picked up from the bedding or the walls of the lambing area or through the lamb's navel. It can be an enormous problem with indoor lambing in particular and will cause unsustainable losses across the entire enterprise.
Remember that E-coli will affect many different species and can be a zoonosis, a disease of animals that can spread to humans. With that in mind, we should observe strict hygiene with a plentiful supply of disinfection and hot and cold water for washing.
When E-coli strikes, it causes the disease known as watery mouth. It also causes scour, navel ill and often spreads to other organs in the body. These include the joints and the brain.
With E-coli in the joints, we see lame lambs with swollen joints, stiff backs and, in general, ill health.
When bacteria invade the brain, they cause meningitis with severe headaches for the poor lamb. Meningitis also leads to nervous signs such as convulsions, staggering and head-pressing. It is usually fatal.
Avoidance and prevention is the best by far. Treatment involves the vet prescribing medicines and giving advice in relation to hygiene at lambing time. Clean bedding, dry floors, lime under the straw and disinfection points around the lambing sheds should come into the flock health plan. Salmonella will be just as invasive as E-coli and preventative care for one will also cover the other.
Some other infectious nervous diseases of young lambs include Border disease, Congenital Swayback and Tick Pyaemia. These are rarer although tick pyaemia and viral louping ill, which may be problematic in hill sheep when ticks are active in spring and summer.
Border disease is a virus that spreads in the flock, similar to BVD in cattle. It comes into the flock usually via the buying of a persistently infected replacement ewe.
Control of the disease involves ridding the flock of the offending diseased animals and putting bio-security measures in place to prevent re-infection.
Lambs with Border disease can be born with jerky tremors visible from birth. They don't thrive and can be described as having fleece similar to a terrier dog. Again it's a rare disease in these parts, thank God, and it's your vet who will be the best guide to diagnose the nervous condition in the young lamb.
Peadar O Scanaill MRCVS, Ashbourne, Co Meath, is a member of Veterinary Ireland Animal Health. Email: Committee firstname.lastname@example.org