The Mycoplasma bovis programme partners – the Ministry for Primary Industries, DairyNZ and Beef + Lamb New Zealand – are encouraging dairy farmers and calf-rearers to make biosecurity a top priority during calving this spring.

M. bovis Programme director Stuart Anderson says that the effort to eradicate M. bovis is making excellent progress, but poor biosecurity practices at calving could result in a long tail of M. bovis infections, drawing out the eradication process.

“There is very little M. bovis infection left in the national herd. Currently, there are just six Active Confirmed Properties, and only two of those have infected cattle still on the farm.

“However, if there are just one or two farms that we haven’t found yet, they can inadvertently spread the infection around the entire country. Just one untagged or unregistered calf could spread infection to an entire herd – so it’s critical all farmers correctly tag calves, register them in NAIT, and record all movements this spring.”

Stuart says achieving lifetime traceability for NZ’s national herd starts at calving. “Accurate NAIT records allow us to quickly track down any calves that have left an infected herd, and to identify all of their close contacts and get them tested to make sure the infection hasn’t spread.”

Raw waste milk also creates a high biosecurity risk – and DairyNZ’s advice is that farmers should not be feeding waste milk to calves. Waste milk can be a source for many diseases and other issues in calves as their systems develop. Read DairyNZ’s advice on waste milk at: https://www.dairynz.co.nz/news/waste-milk-is-it-calf-feed/

Current advice is if you’re supplying raw milk to calf-rearing operations, the milk should be treated – either pasteurised or treated with citric acid – before the milk leaves your farm.

Advice about how to acidify milk with citric acid is available at: https://www.dairynz.co.nz/animal/cow-health/mycoplasma-bovis/

Dairy farmers should also keep accurate and up-to-date records about what farms they have provided milk to.

General biosecurity measures to help protect against many diseases, including M. bovis, at calving include the following.

1. Tag every calf (put the tag in well) that is born on your farm. Bobby calves going direct to slaughter are exempt from NAIT requirements, but require a specific tag.
2. Register that calf into the NAIT system against your NAIT number before it is moved off-farm.
3. Record that movement off-farm in the system within 48 hours.
4. Keep groups of calves separate for 48 hours before mixing them while you observe them for disease.
5. Keep calf-rearing facilities and equipment clean, and limit how many people access calf-rearing areas.
6. Get people accessing calf-rearing areas to clean their boots and personal protection equipment, and any other equipment, and clean them again when they leave.
7. Remove sick calves to a dedicated sick pen.
8. Only buy NAIT-tagged calves with accurate and up-to-date records, and record their arrival on to your farm.
9. If you sell or give away milk for feeding calves, keep a record of who the milk went to.
10. Keep accurate records of all of financial transactions, including calf sales, just in case you have to make an insurance or biosecurity compensation claim in future.