With a few whole herd pregnancy tests under our belts and data analysis courtesy of MINDApro, some interesting results have emerged from this season's campaign of treating non-cycling cows.
Non-cycling cows were treated with a vaginal insert CIDR or Cue-Mate for seven days, with hormone injections given at the time of device insertion and removal. Then 48 hours after device removal, usually at afternoon milking, a final ‘ovulating' hormone was given. This was followed by Fixed Time Artificial Insemination (FTAI) the next morning.
We recommended treatment to be initiated 7-10 days before Mating Start Date (MSD) to maximise early conception opportunities. Depending on numbers of cows not mated by Wk 4, a second wave of treatment was often applied at that time.
So what did we learn?
| Herd Size range | 221-224 |
| Percentage of herd treated | 9-21% |
| First service conception rate (to FTAI) | 34-55% |
| 4 week in calf rate | 36-62% |
| 8 week in calf rate | 60-84% |
| Empty (MT) rate | 7-21% |
Some general observations:
- the higher the percentage of herd treated (a greater non-cycler problem), the lower the 1st service Fixed Time Artificial Insemination Conception Rate (FTAI CR) and higher the final empty (MT) rate. There's also a strong correlation with body condition score.
- 3/6 herds achieved FTAI CR between 52% and 55% - in all these cases, this was better than the 1st service conception rate (CR) for the entire herd.
- the money number is the 4Wk in-calf rate - again wide variation from herd to herd, with the target being over 60%
- MT rates amongst treated non-cyclers were similar to the overall MT rates for each of the herds.
So was it money well spent?
The basis' for the economic gains due to early treatment of non-cycling cows are:
- a reduction in the average interval from MSD to conception of 13-16 days in progesterone-treated cows, compared to doing nothing, resulting in more days in milk in the next lactation - in other words, treated cows conceive more quickly
- as a result of calving earlier next season, treated cows are less likely to be anoestrus next year, so there is diminished risk of them being retreated
With the goalposts shifting sharply on MS payout & cow prices, earlier cost benefit models predicting up to a 3-fold return on investment at a 40-45% FTAI conception rate no longer apply. Instead, more conservative rates of return (75-100%) can be expected in today's market conditions.
Local data indicates there are both upsides and downsides to this range. Those at 55% CR have had exceptional rates of return while for those at 35% CR the exercise will prove to be far less profitable. There is a breakeven FTAI CR point below which treatment of non-cyclers loses you money!
Do you know how well you fared?
Another way of highlighting the positive impact of early anoestrus intervention is to look at a MINDApro Pregnancy Confirmation Report. It is presented here for the poorest performing of our analyzed herds with only a 34% CR.
Note the spike in Wk 2 coinciding with pregnancies to FTAI after Cue-Mate treatment around MSD. Left untreated, few of these cows would have cycled in Wk 2, let alone conceived. The net result is greater lactation days next spring.
How can we help?
Talk to Totally Vets about ...
- measuring response rates in treated non-cyclers
- minimizing the number of non-cyclers in the first case
- the value of being MINDApro registered
- performing an InCalf reproductive review of your herd - what went well; what needs improvement and options available
