In 2012, here at Mount Major Murray Greys we had our first experience of of exporting embryos (out of Mount Major Uplift Tarella C3 by Dajory Dynamic) and the following is taken from an article we wrote for the Murray Grey Annual in 2012. We thought that the lessons we have learned might be useful to others.
We were fortunate that we have an AQIS accredited embryo export centre, Global Reproductive Solutions, practically on our doorstep. They have led us through the process and costing, which is quite involved as there are many considerations.
Step 1 - Select the cow and bull. Different countries and Murray Grey breed societies have different standards for what is classed as “purebred”. For example, not all Australian purebred animals can be registered with the New Zealand Murray Grey Beef Cattle Society, so pedigrees are an important consideration.
Step 2 – Health testing. Cows and bulls need to be tested for a range of health conditions as each country has different requirements for different conditions all of which require different times in quarantine. If you are using semen from a bull that has been licensed for semen export to the required destination, then only the cow needs to be quarantined. As well as health checks, the New Zealand Murray Grey Beef Cattle Society required testing for genetic diseases (AM, NH, CA and Mannosidosis) – being free by pedigree was not sufficient.
Step 3 – Producing and collecting embryos. The cow is super-ovulated to increase the number of eggs produced, inseminated or mated, then flushed to collect the embryos. The embryos are then graded. The number and quality of embryos harvested can vary widely and the outcome is impossible to predict. On average, cows yield six good quality embryos per flush but can easily produce none or as many as 50. This process can be repeated twice, but the performance at the second flush is not likely to be better than the first. We had hoped to get at least 10 A-grade embryos from two flushes but only got 5 overall, even with a boost of hormones for the second flush. It seems that, despite all her other qualities, Tarella is not a great flushing cow.
Step 4 – Transport. Transporting the embryos is probably the most costly part of the exercise as they must be escorted by an AQIS accredited person from the collection centre all the way to the airport quarantine facility. So it is more cost effective to transport larger numbers of embryos rather than individuals.
Step 5 – Transfer of embryos into recipients. At the destination recipients need to be organised at a breeding centre for implantation. We think it is better if these are quiet matrons to reduce the pregnancy risks.
Of course there are plenty of AQIS quarantine and export forms involved, most of which also attract charges. As well as two lots of breed society paperwork, there are flush reports, implant reports and an embryo transfer report to arrange transfer of ownership of the embryos, just as we would if we were selling a live animal.