Is lamb pneumonia costing your business?
If you notice coughing in a large proportion of your lambs, or if you have more pleurisy listed on kill sheets than you think you should, get in touch with us as we are considering trialling prevention and treatment options for enzootic pneumonia of lambs.
Pneumonia is detected in an average of 28% of lambs’ lungs at slaughter, but rates can vary greatly, affecting 6%-80% of animals in each line. The most severely affected (an estimated 7% of lambs) take an average growth rate check of more than 50 grams per day. A 2008 study estimated pneumonia costs the New Zealand (NZ) sheep industry between $1.36 and $3.31 per lamb, with most cases occurring between February and April.
While the viruses (like parainfluenza) and bacteria (like Manheimia haemolytica) which cause pneumonia circulate in all populations of sheep year-round, environmental and animal risk factors come together in late summer to trigger clinical disease. Poor summer feed quality, heat stress (including high humidity, long musters, dusty yards), shearing lambs on the day of weaning, and purchasing and mixing different groups of lambs have all been shown to increase the risk of pneumonia.
There is currently no vaccine registered for enzootic pneumonia of lambs in NZ. A 2015 study by AgResearch demonstrated that a cattle vaccine containing Manheimia haemolytica provided significant cross protection, but it is not labelled for use in sheep.
In the absence of specific preventative measures, you can minimise pneumonia by addressing risk factors. Strategies could include trying to muster during cooler times of day, concreting or covering yards to minimise dust and provide shade during yarding, delaying shearing lambs until after weaning, providing good quality feed to lambs over late summer, and preventing/controlling other diseases such as facial eczema, endophyte toxicity (staggers), and Haemonchus (barber’s pole), all of which put lambs under increased stress during the late summer/autumn.
Let us know if you think you have an enzootic pneumonia problem in your lambs, and we can help you come up with an action plan.