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Topic: Breeding by AI (Read 1347 times)
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Tannenwald Trakehner
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Posts: 935
TANZBRISE by Windfall out of Tariana
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I read somewhere recently (maybe in Equus or one of the other general horsey publications, not sure...) that according to the folks at Cornell, breeding with two packets on two days is silly. This is the old controversy of "does the semen keep better in the Equitainer or in the mare..."
I suspect that we have most often settled our mares with semen from the first packet (super-scientific, I know, but because we have gotten mostly fillies; reasoning being that the likelihood of fillies is higher when insemination occurs more than 24 hours pre-ovulation). My vet had a conniption (however you spell THAT) when I suggested splitting one shipment of two packets between two mares. According to Cornell, this probably would have worked just fine. And is the repeated breeding just another clever ploy of vets working at job security? OK, that is a little on the side of devil's advocate, but you know what I mean...
What do you guys usually do? My vet will probably have a hissy fit again when we breed to a stallion for which only one packet is sent.
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fuzzy
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Curious, who are you using, is it the old Cerro, Haberlein, Stanford crew (I really liked Stanford) or is there some new blood in town by now? If it's one of the old vets, say "HI" for me . . .
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Amanya
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Preliminary
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Posts: 96
Life is Choices
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I asked my repro expert, Dr. Hilda Baisel, to comment on the original post of this thread and she did....I have to wrap my brain cells around this before I'm truly "getting" it, but with her permission, I am posting it here for all. She's a very busy vet during this foaling/breeding season and yet she took the time at midnight to write me this email. It's long, but worth the read.
Her response:
First and foremost---thank you for reading and interpreting information using your noggin---yes horse owners thrive to get their hands on anything and often walk away with an interpretation which is incomplete or worse yet incorrect.
The verdict is out still on where the semen is better off, in a bag where it is chilled thus slowing its metabolism, also it is in a nutrient rich media with antibiotics added---or in the mare where nature intended it to be---unfortunately we are not breeding horses for fertility and therefore probably some of the stallions we use and mares we breed successfully would be culled in nature over time due to their infertility or subfertility. we do know that the likely hood of getting a mare pregnant if bred more than 6 hrs after she has ovulated decreases dramatically. If you put semen in a mare and she does not ovulate as anticipated that semen may not be viable when ovulation occurs---again there are reports of mares bred 4-5 days before ovulation and they still get pregnant---likely a very fertile stallion.
due to the fact we really do not know all the factors which influence fertility in a stallion (ie daily sperm output, motility, velocity, morphologically normal sperm, acrosome characteristics etc.) i do not believe we can say it is "silly" to breed on consecutive days---ideally we aim for pre and post ovulatory breedings---more so with frozen semen than shipped cooled semen. Often times we breed with only one dose of semen--if it is cooled semen we hope the mare ovulates within 24 hours, if it is frozen we aim for a tighter breeding ie within 6-8 hours of ovulation. semen seems to lose some of its viability when frozen therefore does not survive as long. It is interesting to note, in cattle, which we have selected characteristics for fertility, number of spermatazoa used to inseminate and timing seem to be much less crucial.
Do mares really have more fillies with insemination occuring more than 24 hrs pre ovulation--characteristics of X vs Y chromosomes suggest that X chromosomes are longer living thus will survive longer if ovulation is postponed. Alternately if breeding with 2 doses of semen---no sperm gets to the egg until it ovulates!! so--the question is if both doses are preovulatory to 6 hrs post ovulatory and you feel you are getting more fillies did the "filly" sperm position itself waiting anxiously in the oviduct in a more optimal position to penetrate that egg?--many unanswered questions here
In terms of volume--there is a too much, so if you have 2 doses with a total volume over approx 50 cc of semen you may be doing more harm by putting too much volume in the mare such that it is difficult to expel what is not needed and causes a terrific inflammatory response.
Next --can you split doses?---original work in insemination recommended a minimum of 500 million progressively motile sperm per breeding dose for optimal chances of impregnating a mare---lower numbers resulted in lower pregnancy rates. recently we have looked at using much smaller numbers of sperm cells and a much lower volume and inseminating with 2 different techniques which place the sperm cells: 1-- deep in the uterine horn ( similar to regular AI but after feeding the pipette through the cervix you go rectally and guide the pipette deep in to the uterine horn, close to the tip on the side where the ovulatory follicle exists) or 2 similar procedure but actually using an flexible fiberoptic endoscope to deposit the semen at the utero tubal junction.----both are very successful but require a much greather degree of proficiency than "normal AI". In most situations at our clinic we at least aim for deep uterine horn insemination regardless of dose or volume
So there you have my opinion--what i have written off the top of my head here-- the numbers etc are proven---the thoughts on survivability etc are more that--thoughts--if one way worked best im sure all veterinarians would be using that approach but there are many factors which vary--ie horse to horse, and day to day--stallions do not produce the exact same numbers of sperm every day under every collection situation, mares do not always ovulate on a certain size follicle, there may be water droplets left in a collection container or worse yet, soap residue or maturation of the spermatazoa in the epididymus is affected because the stallions immune system was affected with a subclinical challenge---all affecting the outcome.
I do know that from this writers (original poster) "devils advocate" of job security--it is a strange job--obviously you have to love it as the hourly pay is probably close to McDonalds with a tremendous amount of responsibility, education, dedication involved, yes we all have to make a living --but success to both the owner and the veterinarian is a pregnant mare!!! There is nothing more satisfying that working for someone like yourself who wants to be involved and educated and gets the same thrill out of seeing that ultrasound picture of a BABY!! as i do. AND the best is yet to come, hearing that little whinny and the amazing soft reply the mare gives her new born foal!!
A few notes---if you feel it is important or beneficial to pass on this info that is fine-- i have chosen to pass it just to you as i do feel it is important for owners to discuss their concerns and questions with those who the work with and because this is not a "well thought out or researched reply" and is far from complete.
All is very well here at the hospital, and the babies arriving are wonderful!!--so perfect--it is absolutely amazing EVERY SINGLE TIME to realize such a perfect creature could be formed in 11 mos---whoever or whatever anyones higher being is---we certainly are incapable of making something so perfect from scratch!
Please take Kasserine on a walk for me and let her graze on some green grass--I look forward to seeing her if its in her game plan!!!! -----Hilda
Ps/
one other thought. Pioneer has become a Select Breeders Service Affiliate Laboratory---in short, we are freezing semen as an affilitate lab-it is a neat program, very interested in research to improve cryopreservation of semen---from your standpoint they have an excellent web site--granted, many of the articles are concerning frozen semen however, i think you would find them very educational---key words Select Breeders Service ---the main office is in colora MD--its a great site filled with information---look it up when you have a moment--who knows the stallion directory may have a new mate for Kasserine!!---hilda
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Tannenwald Trakehner
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TANZBRISE by Windfall out of Tariana
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Yikes Amanya!   I'll bet the tongue-in-cheek nature of my post was enough to raise the hackles of a lot of vets!
On the timing issue, I think a lot of research has been done on the longevity and speed of the two kinds of cells. I know from past experience that it has proven at least anecdotally true. Most of our experience has been with Kaspareit, who was extremely fertile (semen lived well past the 96 hour mark, and the concentration was always so good that there was typically at least 4x the accepted number of progressively motile cells in each packet).
Our first year breeding to him, one mare was bred with the last cover roughly 2 days before ovulation (she teased out after three days, was palpated at a 34 the day before first cover, and in subsequent cycles has been ultrasounded with up to a 56 and ovulating within 24 hours before teasing out). In the following year, that mare was bred to a stallion whose semen arrived at only 10% within 17 hours of collection, the first cover on a 38, second cover 12 hours later, and teasing out 2 1/2 days later. The year after, she was bred at a 45 and did not tease out for 2 days. All three breedings produced fillies.
Mare number two, bred to Kaspareit twice, was bred shortly before ovulation the first time (she advanced her follicle faster than expected), within 24 hours as her cervix was closed by the second cover. The next time, she was bred on a 42 and a day later, and is known to go beyond 50 before ovulation. Colt first year, filly the next.
Mare number three, bred on a 35 the first time, 38 the last time, ovulates on a 43. Next year, bred only once within 12 hours pre-ovulation (Fed-Ex lost the semen--she was supposed to be bred the day before). First time filly, second time colt.
Mare four's cycle was not documented well enough but had a filly.
Maybe it has to do with the stallion (although it worked with the other one), the longevity of the semen, or whatever, but there is a reason that we have had only two colts. One the mare pulled a fast one, the other we call "Ted-Ex" (the vet calls him "Late-Ex") 
With Kasp I was always confident to inseminate first 48 hours before ovulation, and the semen kept just fine in the mare. Using other stallions we may have to follow more conventional protocol.
Regards to your vet, Amanya, who sounds like a dedicated and kind lady, and one which you are lucky to have!
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Maren
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The Bouncer
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I think Amanya's vet brought up as very important issue--fertility.
In the old days of Trakehner breeding, the mares in Trakehnen were not only evaluated for their conformation, temperament and movement, but also on fertility. Mares not producing well were taken out of the farm, same is true for stallions. Period.
In our modern times we're so determined to get horses in foal we totally foget about this sort of "selection criteris". The guys back then knew why, it kept the breed genetically "healthy".
Some families were superior in all attributes, but died out because of poor fertility. Even today the German National Riding Federation (FN) awards mares that produce a high amount of offspring. Sort of like the honor roll thing with the ATA. It just isn't a selection criteria anymore, but it should be.
Good example: last year in Neumünster at the elite mare auction, which is intended to give young breeders the chance to by superior breeding stock, we saw a young mare of outstanding quality, with mare perfomance test and highest inspcetion marks. This mare was bred for a complete season and never got in foal, with several stallions, some known for excellent sperm quality. She was not in foal when sold as "broodmare prospect" in NMS. Her new owners, who probably thought they bought a wonderful brood mare, have no idea about this. Plus, in general it is the rule that 3 year old and older mares at the auction HAVE to be in foal, except they were shown in riding horse classes.
We should focus on fertility in our horses, at least more than we do right now. This equally applies to mares and stallions, by the way!
Just an idea....... 
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Equine Connection
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Maren - Those are excellent points that need to be taken into strong consideration by both mare and stallion owners. In Germany (and in Europe) in general, do the vets perform a culture/cytology and/or a uterine biopsy (or other tests) on a mare prior to breeding, particularly as a mare gets older? In my experience, the results of a uterine biopsy can provide a better overall "picture", if you will, of the chances for a mare to conceive and carry a foal to term. It's not 100%, but it can be a very good indicator, particularly when one is purchasing a "brood mare." Just curious.
On the flip side, what type of tests, if any, are conducted on a stallion (or prospective stallion) to determine fertility? I can only say in our case that we have our stallion thoroughly checked 2 times/year, inclusive of detailed blood work, as well as semen evaluation, etc., etc., plus a detailed report is included w/each shipment. This provides us with a good baseline from which to follow and monitor his health. It would be interesting to know what the protocol is in Europe to determine a stallion's fertility (or lack thereof).
TIA and have a great day!
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Warm Regards,
Renee & Happy Hour
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