Pneumonia vaccination made easy

As we look back on a busy lambing season, and prepare for tupping, it is worth spending some time reviewing flock performance and seeing what could be improved for the next year.   Labour at lambing is one of the main stresses, with seemingly endless lists of jobs to do so it is rather worrying that a recent, independent study revealed that, on top of the demands of a busy lambing, an outbreak of pneumonia equates to an extra hour’s work every day for three months.  

Given that outbreaks are normally seen in very young lambs, and then in 6-10 month old lambs, vaccinating to minimise the chances of an outbreak seems wise.   Intervet’s pasteurella and clostridial vaccines make up a complete ewe, lamb and replacement vaccination programme.   Lambs should be vaccinated with Ovivac-P Plus, and breeding ewes and replacements with Heptavac-P Plus, to help avoid a potentially very expensive outbreak. These vaccines induce immunity against pasteurellosis, along with the most appropriate clostridial diseases for lambs and ewes respectively. 

The timings of the vaccinations is important, in order to promote adequate immunity.   An injected vaccine stimulates a natural disease challenge without exposure to disease-causing organisms.  Adequate immunity is typically only achievable with two doses of vaccine, administered 4 to 6 weeks apart - the initial vaccine dose stimulates the immune system and the second dose then raises the immunity to a protective level.  Lambs fed colostrum from ewes which were vaccinated with Heptavac-P Plus prior to lambing will have passive immunity against pasteurellosis which lasts for around 3 weeks after birth.   

Pasteurellosis is usually caused by one of two bacteria.   These are Mannheimia haemolytica  and Pasteurella trehalosi, both of which are very common and are found on the tonsils and lungs of many healthy sheep.   An average of six out of every ten sheep harbours these bacteria, rising to 95% in some flocks.   In normal circumstances the bacteria do not cause any disease.   However, there are a number of triggers which cause the bacteria to undergo a change, whereby they begin to multiply, spreading round the body and releasing toxins.   This can lead to sudden death with very little or no warning.

“Pasteurellosis in sheep is responsible for many unnecessary and unwanted deaths every year,” states Intervet’s Rosemary Booth. “The unpredictability and rapid onset of an outbreak of septicaemia or pneumonia, and the relatively poor success rates of antibiotics, clearly demonstrates the importance of a comprehensive vaccination programme.   It is a relatively small cost to pay for year-round flock protection against pasteurellosis and clostridial diseases, improved animal welfare and peace of mind.”

Article first published 28/04/06