Treating Non-cycling Cows

In the past few years there have been 3 major changes to  our recommendations for the treatment of non-cycling cows (NVO's).

Field trials have been conducted on an ongoing basis and recent results confirm that these changes result in more non-cyclers in calf to AI, and that the programs are economically sound.

So, what are these changes?

  • Fine tuning medication
  • A combination of CIDR'S, oestradiol, and prostaglandin given at the correct timing allows the majority of non cyclers to be presented for
  • Early Identification and treatments of NVO's
    • In the past we would examine and treat non-cyclers 3 - 3 1/2 weeks after mating start date (MSD).  While the response to treatment was very good, it meant that these cows cycled 4 - 41/2 weeks into joining, and in most AI programs, had only one chance to conceive to AI.

      If we identify the non-cyclers prior to MSD it means that the first insemination is very early in the joining period, and they have at least one more chance to conceive to AI.
  • Retreatment of mated Non-cyclers
    • The InCalf study results and recent trial work has allowed us to identify a group of cows called "phantoms."  These are cows that cycle and are inseminated but then fail to show any further signs of heat for many weeks, despite not being in calf.

      They are the cows that you believe are pregnant but are only identified as empty when they cycle weeks later or are picked up at pregnancy testing.

      Cows that fail to show a heat prior to MSD ie: the non-cyclers; are much more likely to become phantoms.

      Retreatment of the non cyclers, using oestradiol and the previously used CIDR, results in a significant reduction in the number of these phantom cows, and an increase in the number of cows in calf to AI.  Treatment does not harm those that are already pregnant.

 

The steps for managing non-cycling cows are:

  • Identify them early using tail paint, heat mount detectors or observation. Start one month prior to MSD.
  • Arrange for them to be examined and have the appropriate treatment in the week prior to MSD.
  • Retreat after the 1st round of inseminations.


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