With 2014 lamb prices running ahead of 2013 levels, sheep producers are being urged to realise full value for this year’s crop by making sure young lambs on the farm are vaccinated against pasteurellosis and the main clostridial diseases.
According to MSD Animal Health (known as Merck Animal Health in the United States and Canada) livestock veterinary adviser John Atkinson MRCVS, lambs can succumb to pasteurella and clostridial diseases within hours, often with no warning signs of a disease outbreak.
“Sudden death and pneumonia are responsible for significant losses of unvaccinated lambs each year.
“Many disease outbreaks are caused by pasteurellosis. Pasteurella are a group of bacteria, with Mannheimia haemolytica and Bibersteinia trehalosi being the most important types to cause disease in sheep. Flock problems usually start with sudden deaths, often in young lambs. But occurrence can be sporadic in individual sheep. Clostridial diseases like pulpy kidney, braxy, blackleg and tetanus are also a key threat to unprotected lambs and typically the first sign of any problem is a dead animal,” he warns.
Unfortunately, the colostrum lambs receive from a vaccinated ewe shortly after birth only gives them disease protection for a limited time.
“If ewes are on the HEPTAVAC-P PLUS system and have been boosted in the run up to lambing then their lambs will also gain immunity from drinking her colostrum. But this so called passive immunity only lasts for so long. Lambs that receive a good intake of colostrum only have antibodies against pasteurella for up to four weeks and clostridia for up to 12 weeks. This means that some early season lambs may already be unprotected and at real risk from these prevalent disease threats unless they are vaccinated themselves,” John Atkinson says.
Lambs can be protected themselves by vaccinating them with either HEPTAVAC-P PLUS or OVIVAC-P PLUS from three weeks of age. The primary course involves two 2ml vaccinations 4-6 weeks apart. The first dose is a primer, while the second produces effective immunity. Animals that are intended to be kept for breeding simply need a booster of HEPTAVAC-P PLUS within 12 months – given at the same time as the rest of the flock get their annual pre-lambing booster – with an annual booster 4-6 weeks before lambing every year thereafter.