Lamb Vaccination

Vaccinating your lambs should be a standard procedure for producers as the animal health, production and economic benefits are well known. Most producers do it right, but there are some who don’t – exposing their lambs to unnecessary disease risks and themselves to unnecessary economic loss.

One area where some producers can improve is the all-important second vaccination for lambs. The recent PIRSA Animal Health sheep producer survey showed that a number of producers are only giving their lambs one vaccination, usually at marking, leaving the lamb with less than optimal immunity.

A successful vaccination program will get these things right:

The type of vaccine
The number of doses
The timing of the doses
Storage and handling of vaccines.

The vaccine used should provide protection against Cheesy Gland (CLA), and at the minimum also cover Tetanus & Pulpy Kidney (Enterotoxaemia, Overeating disease) i.e. a standard 3-in-1. In some areas, or in more valuable stock, a 6-in-1 is recommended as it covers a wider range of Clostridial diseases. Your local Animal Health Officer, Veterinary Officer or private Veterinarian can advise you on vaccine choice. For the purposes of this article we will look at these common vaccines and not at the more specific ones that protect against scabby mouth, Erysipelas or OJD.

When using vaccines containing trace elements or anthelmintics ensure the correct dose is used to avoid under or overdosing.

If ewes are vaccinated correctly, their lambs will obtain antibodies through the colostrum (first milk) which will give them some protection for the first month or two of life. Vaccinating lambs at marking acts as a sensitising or priming dose that stimulates the lambs’ immune system to protect for approximately 6 weeks. Remember that it takes the immune system about 2 weeks to fully respond.

A second dose given 4 to 6 weeks later, or at weaning, is vital. This dose will further stimulate the immune system, resulting in a prolonged level of protection. This can last out to 12 months and really set the sheep up for ongoing immunity using annual boosters. Weaners going on to high-quality pastures or being supplemented with grain are more at risk of Pulpy Kidney, and should receive booster vaccinations every 3-4 months. Booster doses can be given when the lambs are in the yards for other reasons, e.g. drenching or drafting off a line for sale, to save on labour & time.

With the lamb, sheep and wool markets at the levels they have been recently, why not give your lambs the best chance to survive and grow? The economic loss of one good lamb to a vaccine-preventable disease is roughly equivalent to the cost of 500 doses of vaccine. That’s got to be a good enough reason to do the job properly.

Article written by Dr Nigel Baum, Veterinary Officer, Disease Surveilance, Biosecurity SA