Can anyone tell me what the difference is other then one being human and one not? Which is better for inducing ovulation?
[QUOTE=Rendaivu;6130677]
Can anyone tell me what the difference is other then one being human and one not? Which is better for inducing ovulation?[/QUOTE]
They are two different “drugs”. Chorulon is HCG and Surcromate is deslorelin. We only use the Sucromate, b/c we’ve had better luck with it more tightly controlling the timing of ovulation. However, HCG often works just as well; the only thing to be aware of is that some mares can develop antibodies to the HCG when it is given multiple times, and thus they may fail to respond to it.
That is it in a nut-shell, I’m sure Kathy can come on here and give a ton more details, but I’m a little pressed on time right now 
SucroMate is otherwise known as deslorelin. It is extremely reliable as far as ovulatory stimulators go, for inducing ovulation within 48 hours of injection. SucroMate is a synthetic gonadotropin-releasing hormone (GnRH) analog suspension in a sustained release formulation and is given when the mare is confirmed in heat and has a follicle between 30 and 40 mm in diameter.
Chorulon is the same as hCG, thus it’s a real hormone (as opposed to synthetic) and again is also used as a very reliable ovulatory stimulator and will stimulate ovulation within 48 hours. Chorulon was the drug of choice for my vet to use on my Dutch mare who was trying to grow 2 follicles simultaneously as Chorulon tends to stimulate the most dominant follicle and encourages the formation of a corpus luteum (CL). Chorulon can also be used to induce luteolysis to promote timely return to estrus.
I think either/or drugs can be used as ovulatory stimulators successfully with little muss or fuss.
The only disadvantage to Chorulon is in repeated uses in the same season, the mare CAN develop antibodies to it. This would only be a problem if you’re rapid cycling constantly in order to AI and flush multiple embryos wtihin the season. In this scenario, it is perfectly reasonable and safe to just switch to the deslorelin. But to use Chorulon when you are anticipating at most 1-3 attempts to get your mare pregnant, it’s not really much of an issue.
It’s funny to me to read about the possible issue with HcG because I had a mare who could NOT have deslorelin. One breeding season was lost due to the vet giving deslorelin the first cycle, it shut the mare down completely. She was in the clinic for over a week and never ovulated, and for the entire summer, she never cycled again. So I had to remind my vets every year NOT to use deslorelin on her.
One breeding season was lost due to the vet giving deslorelin the first cycle, it shut the mare down completely.
That happened to a lot of mares when it first came out. Not sure it is still an issue
HCG is more timing sensitive and works great when the follicle is 35-40 on a progressive cycle but not so reliable when bigger. I never had a problem with it working on ET mares that got it 5 times in a row but that may be different with some.
While it has been clearly demonstrated that antibodies are developed following use of hCG, there is still plenty of debate as to just what effect those antibodies truly have. It has been published that issues of refractoriness typically do not appear until after 2 or 3 consecutive cycles of use - and let’s face it, if one is breeding a mare 3 consecutive cycles with no pregnancy, then there are plenty of other things to worry about as well!! I will add that all horses are not created equal and that mare is a four-lettered word, so while the above may apply to the majority of mares, there may always be exceptions.
Sucromate Plus is a Deslorelin product new to the USA market in 2011 that uses, I believe, SABER delivery technology (a time-release agent). Sucromate Plus is an FDA-approved product, which means that any compounded Deslorelin product now being marketed by a compounding pharmacy is in all probability being done so illegally. Sucromate Plus has demonstrated reliable results in regard to the timing of ovulation relative to treatment in the face of a follicle >30mm in diameter. It is not, however, particularly cheap.
Ovuplant was the FDA-approved Deslorelin implant that was formerly available in the USA but which was withdrawn from that market several years ago as a result of prolonged anestrus periods being induced in a significant percentage of mares that received the treatment but did not become pregnant. This issue was mitigated to some extent by the surgical removal of the implant several days after it’s being placed, but this again increased cost and as a result many breeders elected not to use it.
Another ovulation-promoting hormone is now available in the USA. Histrelin. This is available in a biorelease formulation (i.e. time-release - and incidentally developed by the same person that did much of the initial work on Sucromate Plus) and is obtainable from BET Pharmacy in Kentucky. We worked on some of the initial clinical evaluations and have continued to use it in subsequent years and are very pleased with the results. It is somewhat cheaper than Sucromate Plus which is an added bonus.
HFSH - I have a similar mare. HCG is fine for her, but if we pull out the Deslorelin she just shuts down after the cycle. In her case, she will ovulate but then never comes back in without a great deal of assistance.
Glad to hear my mare isn’t the only one, although I think that she’s in a small group! :lol:
I used the Histarelin last year and did not have very reliable results with it at the lower dose ( which was originally recommended). At the higher dose, it worked but did not give me very much of a cost savings
