Pregnancy Testing

Cambridge Veterinary Services offers both manual and ultrasound pregnancy testing services for cattle, and ultrasound pregnancy testing for alpacas.  We have trained operators with proven experience and equipment.  We can combine testing with reproductive analysis to ensure you know how your herd is performing.

Why Pregnancy Test?

Pregnancy testing of cattle is a very useful management tool.  Different approaches will be required depending on the management situation and what you wish to know.  It allows you to achieve many goals if done at the right time.

Which method?

In situations of small numbers of cows, we will almost always use manual pregnancy testing, because it is faster, and because the ultrasound equipment is expensive and requires adequate restraint of the cow.  Manual pregnancy testing also requires good facilities for the safety of people and cattle.  A strong cow race is a minimum requirement, a headbale is better.

There is much debate on which method you should use.  As far as accuracy is concerned they are both fairly even as long as the tester is experienced.  They both have limitations in that they will only accurately date pregnancies between 6 and 16 weeks.  After this time they both fail to see enough of the uterus to be very accurate for dating.

There is a very small risk of rectal rupture with scanning that does not exist with manual testing.  Both can be done at the same speed if you are well organised.  Cows will tend to strain more following manual testing.  All cows scanned empty should be checked manually before being culled.  We will do this as we scan the cows.  Accurate recording of results is vital and empty cows should be permanently marked.  Good tag numbers are essential.

Timing

The Best option

Alpacas can be ultrasound pregnancy tested from 4 weeks up to four months.  Adequate facilities are required, talk to your vet.
Scanning can be done 6 weeks after mating in cattle.  For manual  and ultrasound testing we prefer to wait 8 weeks before confirming cows are empty.

One off whole herd testing

If whole herd testing is done eight weeks after the end of mating it is possible to remove all empty cows.  This prevents the costly burden of carrying empty animals through the winter.  This is  especially so if you are looking for culls in a dry summer.  It can be difficult to give accurate calving dates at this stage if mating started several months before as most of the pregnancies will be too advanced.  This goes for scanning as well as manual palpation.  We simply cannot size the pregnancy accurately after 16 weeks.

Heifers too?

It is also a valuable exercise to pregnancy test heifers.  This allows earlier heifers or those in calf to AB to be sorted from later or bull mated heifers.  Late heifers may be culled early or selected for sale.  Again timing is important to ensure you get the most out of it.

Purchased stock

Finally any stock you buy should either be tested before purchase and certified in calf or tested once you get them home with right of return if empty.  An empty cow isn’t worth much on the hooks compared with an incalf one in your herd!  Make sure you check these cows.

Please note that research has shown a consistent occurrence of 2-5% foetal resorption before 12 weeks of pregnancy in cattle which is not related to pregnancy testing.  After 12 weeks this drops to 0.5%
1-2% loss of pregnancy (slips) is accepted as normal in dairy herds.