Biosecurity essentials for buying livestock
By Dr Pat Kluver, Livestock Biosecurity Network
By far the greatest risk for the introduction of disease, weeds and pests on farm, is the purchase of livestock. A good biosecurity strategy will go a long way in minimising the disease risk with purchased stock, and it doesn’t have to be expensive or elaborate. It can be broken down into three stages:
- Farm gate
Biosecurity considerations should start before you buy livestock.
Stage 1: Pre-purchase
Pre-purchase is all the background checks and physical examinations you do before deciding to buy.
It’s simple – if the animals don’t come with a cattle health declaration (CHD) or sheep health statement (SHS), don’t buy them. These documents contain most of the history you need to do an initial risk assessment.
Only buy from reputable vendors, and limit the number of lots you buy – the more sources you buy from, the greater the risk. If you bought last year and were happy with the stock, buy from the same producer again, or buy direct.
You should examine the animals to make sure they have no diseases. If you’re not confident doing this, ask someone to do it for you. For sheep, look for evidence of lice or footrot, and for cattle look at general health and parasites.
Stage 2: Farm gate
When you get your livestock home there are a few things you should do straight off the truck:
For sheep, a footbath in zinc sulphate should remove any footrot bugs acquired in the saleyards or on the truck. However, if the sheep have pre-existing footrot, this footbath is unlikely to cure it.
All stock will need a quarantine drench to remove resistant worms. This must contain a mixture of four different actives for sheep, and three actives for cattle.
If your stock comes from fluke country, an effective fluke drench should also be given.
Keep them in the yards for 48 – 72 hours to allow them to empty out of existing worm eggs and then check them with a faecal egg count 10 – 14 days later to make sure the drench has worked.
Stage 3: On-farm
Despite doing all the checks and induction treatments, new stock still pose a disease risk. Keep them segregated or isolated from other stock until you are sure they don’t have any unwanted disease; observe them, let them settle into their new environment, and empty out of any weed seeds.
Stock in quarantine can be moved and can be drenched; however, the golden rule is that other sheep can’t cross their path for seven days. If they must be drenched, do them last, and no other sheep should go up the laneway or yards for seven days. If they need to be moved, other sheep can safely enter the old quarantine paddock after seven days.
Cattle need to be isolated for a month, and sheep until you know they are free from lice or footrot, either at the end of spring and six months for lice.
When buying rams, they should come from Ovine Brucellosis accredited free flocks – never buy cull rams from saleyards.
When buying bulls, make sure they are vaccinated for vibriosis, (a silent venereal disease that causes fertility issues) and are negative for pestivirus (this information is contained on the CHD).
Minimising the disease risk with introduced stock requires a little effort and some planning, but in the end costs very little and the returns are immediate, ongoing and cumulative.