bullWhat’s the difference between AI (Artificial Insemination) and AB (Artificial Breeding)?

None - it’s the same thing. The term AB is only used in New Zealand and Australia. The rest of the world uses AI. In AI, sperm is collected from a bull and then, after dilution, is used either fresh or frozen to inseminate a cow on heat.

When will your cow start to cycle?

A cow will cycle (come on heat) about three weeks after calving, but it is more likely to be six weeks. The cow cycles every three weeks - varies from 18-24 days.

How long will she be in oestrus (on heat)?

This will vary from about 12 - 24 hours. Oestrus will start off with low intensity, rising to a state of “standing heat” when the cow will stand quite still to be mounted. After this heat intensity will decline as she goes off heat.

What are the signs of cattle in heat?

  • Clear mucous coming from the vulva.
  • Restless - walking a lot
  • Roaring - seeking company
  • Forming Sexually Active Groups (SAGs) and mounting each other.

What is a short cycle?

This is when the cow has been mated and will come on heat again after a shorter interval than the normal 18-24 days. For example she may come on after 10days - a common abnormal interval. Don't worry - mate her again, and if possible use the same bull's semen.

What is a silent heat?

This is when the cow fails to show heat signs but has ovulated (shed an egg). This is very frustrating as you have lost three weeks in time. Hopefully she will come on heat again in three weeks. The cow may have a silent heat for the first one after calving, and then start normal cycling after that.

How do you use tail paint?

Here you paint a short strip ( 100mm wide and 150mm long ) along the tail head of the cow. Use thick gloss paint or buy some tail paint from the vet. Put plenty on. When the cow is mounted by another cow, the paint will be scuffed and some rubbed off. It's a good indicator along with other signs. She may also have skin rubbed off her back bone.

Use one colour and after the cow is mated change the colour. Use the traffic light colour sequence.

Does suckling calves delay return to oestrus?

Yes it does. Suckling one calf may not delay things much, but if you put more calves on the cow, then expect a delayed return to oestrus by quite a few weeks

Will a bull nearby bring cows into heat?

Yes - sometimes. Farmer experience shows that if cows or heifers are slow to cycle after calving, walking past the bull to milking will help stimulate their breeding cycle. So it could be sight, or smell or both that does the trick.

What is a teaser bull and how are they used?

A teaser bull is vasectomised so he is sexually active but does not ejaculate fertile sperm. He fires blanks! Teasers are used to identify cows on heat which can then be put up for AB. They have all the dangers and disadvantages of keeping entire bulls.

When is the best time to AI the cow?

  • Inseminate her when she is going off heat, or has just gone off heat.
  • This is when she ovulates.
  • So in practice - if you see her on heat in the morning, AI her in the afternoon of that day if you can.
  • If you see her on heat in the afternoon or evening, AI her the next morning or early afternoon.

Where can you buy semen and an AI service?

Look in the Yellow Pages under Breeding Services. There is a wide choice of providers.

How to make the AB technician’s job easier?

  • This is important, as there is evidence that a stressed, frustrated technician will not achieve top results.
  • Have the gates open to your cattle yards.
  • Have a decent set of yards and a proper race so the technician can get behind the cow safely with no risk of accident.
  • Remember you could be liable under OSH for having an unsafe workplace if the technician has an accident.
  • Have a clear bench space for the technician’s equipment.
  • Have the cow or cows handy to the yard, or in the yard waiting.
  • Have someone there to help get the cows in and restrain them.
  • If you have ordered frozen semen, have bucket of cold water handy to thaw the semen straw.
  • Don’t change your mind from what you have ordered.
  • Have a rubbish bin at the yards and keep the place tidy.
  • Avoid what sperm hate:
    • Smoke - no smoking
    • Sunlight - have a shady shed
    • Chemicals - don’t spread disinfectant or chloride of lime all around.
    • Cow muck - keep the place clean
  • Provide a washing facility for the technician.
  • Remember the technician has to keep moving so don’t hold them up.

How do you treat a cow after AI?

  • Let her out of the bail into a small area on her own if she will stay there.
  • If she’s getting upset at being lonely, give her a mate for company.
  • Try to avoid putting her back with the rest of the cows till all the riding activity has gone off.
  • Quiet handling is important.

Stray electricity

There has been a documented case of cows having drunk after being inseminated at the trough near the farm dairy. Stray voltage leaking underground to this trough from poorly earthed electric fences was enough to kill the sperm inside the cow. Maybe a rare happening but it’s a good idea to check that your electric fences are all properly earthed and wires near troughs are well insulated, before the start of the AB season.

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