Conception rates are substantially reduced when semen is not stored and handled correctly or when technique is flawed. Australian InCalf research has shown that at least 40% of do-it-yourself technicians could have at least a 5% increase in conception rates by improving insemination practices.
In preparation for mating ensure you have a well-planned system with your farm team and have the necessary supplies at hand. Assist your AB technician and complete the on-farm mating record book before they arrive and if multiple sires are being used, organise/mark cows to help the technician get the right straw into the right cow.
Cows should be inseminated at the first opportunity after they have been seen in standing heat. Cows seen in heat at the evening milking should be inseminated the following morning. Cows seen in heat at the morning milking should be inseminated that morning. There is no advantage in inseminating more than once per day.
When to inseminate cows
- Cows are in standing heat for 18 hours on average (range 6 - 24 hours).
- Ovulation occurs 14 hours on average after the end of standing heat.
- Good quality semen has an effective life of about 28 hours in the reproductive tract of the cow.
- On average, the ovum remains fertile for about 6 hours.
Assessing AI technique
Conception rates are reduced substantially when semen is not stored and handled correctly or when insemination technique is flawed.
The non-return rate can provide an early warning of a low conception rate and is a worthwhile first check. If, from your Fertility Focus report, the 2-24 day non-return rate for your herd is less than 64%, or conception rate is low (less than 53%) you need to investigate potential causes.
Causes of high non-return rates
Causes to investigate and recommended action.
- Poor body condition at calving or excessive loss of body condition following calving – review body condition score targets and herd nutrition.
- Inaccurate heat detection – review your heat detection programme.
- Excessive numbers of late calvers – review calving pattern.
- Excessive numbers of treated non-cyclers.
There are other possible causes of low non-return rate and low conception rate. You may need to seek help from an InCalf adviser.
- Poor inseminating practice – report your concern to the field supervisor of your AB service.
It is difficult to assess an AB technician from a single farm; however, their field supervisor can access results over several herds. These results can also be compared with those obtained by different technicians working in the same herd.
Assessing technician non-return rate
The 18-24 day non-return rate is used by breeding companies to monitor AB technician performance. The eligible inseminations exclude short returns (24 days). Be aware that the (2-24 day) non-return rate reported on your Fertility Focus report is likely to be 10% less than the 18-24 day non-return rate of eligible returns used to monitor AB technicians.
If you are a DIY technician a disadvantage is that if the non-return rate or conception rate is low, it is difficult to determine whether your technique needs improving or whether other factors other are reducing the conception rate.
Australian InCalf research has shown that at least 40% of DIY technicians could achieve at least a 5% increase in conception rates by improving insemination practices. Consider the following actions to help improve your technique:
- practice your technique on cows in heat before mating starts (this can be done without using semen by placing a sheath over the pistolette)
- have your technique checked by the local AB service supervisor on the farm
- attend a refresher course if you have not done one for two years or if you are not confident with your technique.
For information on semen storage and handling and insemination technique refer to the InCalf book.