Sheep VAI in VA September 2011

[lambchop]

You should have had much better results from your surgical AI. We AI around 100 ewes at a session, and expect to get 70-85% of those ewes settled, with 100+ lambs produced. With the cost of importing semen, It would be very expensive if results were like what you achieved. We have had a few years of 60% settled, but many more of 80% or more.

[Darroll Grant]

Our AI success has been similar to Paul's report. Our ET success has been a 60-75% live drop of embryos transferred IF the program was done here. Whatever the procedure, I concluded after the first year that I had as much or more influence on the program success than the technician doing the technical work.
I would not be surprised if there was variation between breeds as to their response to the same AI protocol. Maybe the BW need some tinkering with the program and optimal time to AI.
For me, it is essential to know the experience level of the technician. I have also asked for references. But then I am writing a significant check when the work is done.

[cjhiemke]

Oogie, what concentration of semen is used for your VAI? Is this technique considered trans-cervical or is it a precervical deposit?

I ask because am coordinating an export of Shropshire semen to Norway. The semen should leave in a couple weeks. Norway can not do surgical AI. Instead the Norwegians use a precervical drop technique, which requires a much higher concentration of semen.

For LAI we'll use semen put up at 50 million, but for Norway we had to put up semen at 250 million live. Putting up semen at 250 million proved to be a tremendous challenge. Many extenders were tried. Finally we ended up with 310 straws put up with acceptable post thaw motility. Ian McDougal of the UK was a consultant for this collection.

The cost to put the higher concentration up is 5x more than it is to put up the LAI semen. Although VAI might be less expensive because it does not require a trained technician, the semen cost and conception rate might even things up a bit more.

I have heard that trans-cervical AI is less successful on ewes when done in successive seasons on the same ewe. I beleive the theory was that damage was done to the cervical folds resulting in poorer results in the following years. If this is a transcervical technique has there been any discussion of differences in concentpion rates in sucessive seasons on the same ewe?

Thanks,
Cody

[Darroll Grant]

Cody,
I can understand an increase in time to put up the higher concentration due to more collections to get the same number of units, but any differences in extender cost should be minor. Any idea as to why the 5x increase in cost?

[OogieM]

Been at the Colorado Woolgrowers meeting for the last 2 days, let me try to answer all the various questions for you all.

First off the AI seminar is not likely to happen now,because not enough people signed up for it. :sigh: You can always call her about it and talk to her directly, that's the best option at this point. I don't know that it's absolutely for sure not going on but it sure looks that way.

On the rates using surgical and why so low. We believe there are significant issues with different breeds. I used 2 different techs, Martin Dally for the first attempts and Glen Erickson for the second. We used sponges from Martin Dally in on 1 August 1999 starting at 6:30 am . Finished at 8am doing 10 ewes. Pulled sponges starting at 1am 15 August 1999 and gave 200 IU PMSG. Finished at 1:30 am. One ewe had lost her sponge. Surgeries started afternoon of 17 August 1999. 9 Black Welsh ewes bred, 2 pregnancies 2 lambs.

Second attempt We inserted sponges starting at 2:30pm on 29 November 2004. We finished doing 23 ewes at 3:30. 17 for AI and 6 to synchronize for natural cover. I kept track of ewe tag numbers and we did them in the order in which we planned to do surgeries with each group of ewes being bred to a particular ram done sequentially. Sponges came out and ewes were given either 400 or 450 IU of Folligon PMSG Lot 21559A exp 01/2005 starting at 9am on 11 December 2004. We finished pulling sponges at 9:25 am. The dose was based partly on body weight. Smaller ewes got a lower dose, larger ewes got a bigger dose. Again, each batch of ewes being bred to a particular ram was done in order and that is the same order in which we did the surgeries. We started teasing ewes with a ram on 12 December and teased regularly that day. By 1:30 pm on 12 December we had 4 ewes in strong heat, 5 also showing, 6 possible and 2 not in. Surgeries started at 5pm 13 December 2004 and we finished the last ewe at 8:30pm. Of the 17 ewes bred AI we got 12 pregnancies and 19 lambs. For next time, the vets think we should give all ewes a 450IU  dose of PMSG. Also, surgeries should start a few hours earlier, perhaps as much as 4 hours as it appeared we were on the tail end of heat cycles according to the teasing results with the rams.

For surgical AI the semen is frozen and tested to produce 50 million forward progressive motile sperm post thaw per dose.

In Black Welsh Mountain sheep in the US over all flocks that have tried surcial AI the results are:

Black Welsh AI Data
41 ewes inseminated
22 pregnancies
35 lambs produced
These rates are similar to the AI rates seen in Wales on other Welsh Mountain breeds using surgical AI. We might get a bit better with more study but the cost of the semen is $100/dose.

On the transcervical AI semen is frozen so that we use 400 million forward progressive motile sperm post thaw per dose transcervically.

No difference in fertility in ewes bred AI one year and natural service another. Two different sync protocols have been used. We have used sponges to sync, CIDRs and also bred on natural heat cycle by ewes showing to a teaser ram. The sync with CIDRs did mess up the cycles of the ewes so that many did not settle at all even to the live backup ram that year. However, many of those same ewes did settle the next year to natural service so it wasn't a permanent problem.

Hopefully that answers more of the questions folks have had.

[cjhiemke]

Funny how the sheep world works. I'm in Utah for work. Two hours ago I was sitting at Glen Erickson's kitchen table and I began asking him questions pertaining to this thread. He said, is Darroll Grant on that forum you speak of?? He also mentioned he had done same AI with Oogie.

Darroll, I need to clarify my earlier statement. The 250 mil straws SHOULD cost 5x the 50 mil straw. It took Glen 5x the ejaculates and 5x the time (actually more than 5x because of the extender challenges) to put up an equivilent amount of 250 mil straws as 50 mil straws.

Now, Glen's realistic and realizes he can't charge 5x. Frankly, we haven't figured out the costs for the extra special semen collection project (he also got federal approval to export to EU and Norway for this scenario). They will surely be more than we thought in the onset, but also won't be a true represenation of Glen's time put into the project. I would like to think we are much smarter coming out of the experience than we were going in!


Oogie, thanks for the additional information. I will do my best to come up with the pre-cervical deposit protocol my friend will use in Norway. I think there is a lot of value in a pre-cervical (minimally invasive) technique if the success rate is cost effective.

As an FYI, Glen confirmed my recollection that repeated trans-cervical AI on the same ewe in successive seasons is increasingly less successful. But he qualified that saying others have had different experiences and will debate him on that.

[OogieM]

I will do my best to come up with the pre-cervical deposit protocol my friend will use in Norway. I think there is a lot of value in a pre-cervical (minimally invasive) technique if the success rate is cost effective.

I'd really like to see that. We really need the ability to do AI as that is the only way to get new genetics into our breed in this continent but the costs are prohibitively expensive for the surgeries. Last time I did it I figured on about $750/ewe what with the cost of the tech, semen importation etc.

[Darroll Grant]

The surgery is the cheap part for us. With expensive semen it will go in surgically for us until some nonsurgical method is well proven. Even if semen for nonsurgical use was just double cost of that for lap AI, resulting lambs would still be cheaper by lap AI.

[OogieM]

For us there is no difference in cost to get semen in for non-surgical vs surgical AI and the surgery costs far outweigh semen costs by an order of magnitude. SO for me I need a non-surgical route to make it at all doable.

[woolpuller]

We only use surgical AI. Tried other (transcervical) 3 times with only 30% but with the vet we are up to 80%.
Always looking for good frozen Suffolk semen with data that can come to Canada.

[Muleflock]

We only use surgical AI. Tried other (transcervical) 3 times with only 30% but with the vet we are up to 80%.
Always looking for good frozen Suffolk semen with data that can come to Canada.

Hi Bill

I have a lead on one with good numbers coming from the UK to Canada.