question on twins

onalimb · Postby **onalimb** » Sat Jan 08, 2005 5:33 am

I was reading on another post that twins can't be registered with jockey club is that true and why. onalimb

NYBreeder · Postby **NYBreeder** » Sat Jan 08, 2005 5:59 am

Sure they can. There were two sets of twins racing together last year. However, most twins are not considered viable atheletes. If you have a male/female set the filly is almost always sterile and can act very studdish.

Mahubah · Postby **Mahubah** » Sat Jan 08, 2005 7:39 am

NYBreeder wrote:If you have a male/female set the filly is almost always sterile and can act very studdish.

Interesting; I didn't know this was the case in horses, although I've seen this reported for cattle, where the female twin of such a pair is referred to as a "freemartin." Haven't the slightest idea where that term came from.

LSB · Postby **LSB** » Sat Jan 08, 2005 8:06 am

I didn't know that either. Thanks for the information, NY Breeder.

henthorn · Postby **henthorn** » Sat Jan 08, 2005 8:47 am

I suspect that most twins don't race because they are usually much smaller than their single counterparts. And I bet there are lots of twin mares out there who foal just fine. I suspect in many cases, one foal is healthier and bigger than the other, and can go about life normally. Some mares can support two full-sized foals, but most can't. There is only so much room and only so much nutritional support available.

Gerry · Postby **Gerry** » Sat Jan 08, 2005 8:59 am

Twins do tend to be on the smaller side. I had a very nice Cannonade mare that was only 14'1, her twin died at birth and this poor mare only had a couple of foals. But on the other my mare No Coverage is a 1/2 sister to twins Penny One and Penny Two. Penny One was a winner at 3 and a stakes producer, Penny Two was unraced but she also was a stakes producer. The fact that they even survived was a major feat since they were foaled in 1973.

Mahubah · Postby **Mahubah** » Sat Jan 08, 2005 9:04 am

Spectacular Bid's second dam Stop on Red was a twin. She and her twin Go On Green were both winners and both produced winners, but Go On Green seems to have been barren a lot -- don't know if that had anything to do with her status as a twin or not. Stop on Red was definitely the better producer since she threw a couple of minor SWs.

trcampidilli · Postby **trcampidilli** » Sat Jan 08, 2005 10:28 am

Okay-is it a possibility that a female twin will be sterile. But it is not always so, and it that something a vet can determine. Or do you just try to breed them. What makes them act study if they are sterile?

Mahubah · Postby **Mahubah** » Sat Jan 08, 2005 12:32 pm

I assume the studdish behavior would be due to brain changes from being exposed to the hormones of the male twin while in the uterus.

austique · Postby **austique** » Sat Jan 08, 2005 12:34 pm

I'm probably going to really mess this up since its been a while since I had growth and development but I believe hormones are passed between the two foals during the reprod. tract development which cause the female's tract to not develop and produce excess testosterone making them studdy. I'll have to find my notes from that class.

jellac · Postby **jellac** » Sat Jan 08, 2005 1:25 pm

AS long as we're discussing 'twins theories' I recall reading a paper or treatise some years ago - OK it was at least a decade(!) - that made the case for the surviving twin colt to have the potential of becoming a prepotent sire, even if born undersized and very small. What I can't remember is the 'examples' that were cited to advance this theory. Anyone else here recall this.....or is my mind playing tricks on me....again?

rascal · Postby **rascal** » Sat Jan 08, 2005 5:50 pm

What are the true odd of there being twins in horses? I think I read that it's something like 1 in 10,000 pregnant mares, one of the embryos usually being absorbed when the mare was unable to support the development of 2 foals. Interesting thread here and hope your mare has 2 healthy foals, Onalimb!

trcampidilli · Postby **trcampidilli** » Sat Jan 08, 2005 9:18 pm

jL · Postby jL » Sat Jan 08, 2005 11:10 pm

rascal wrote:What are the true odd of there being twins in horses? I think I read that it's something like 1 in 10,000 pregnant mares, one of the embryos usually being absorbed when the mare was unable to support the development of 2 foals. Interesting thread here and hope your mare has 2 healthy foals, Onalimb!

Until I was exposed to a horse farm where there were several broodmares, I too thought the occurence was rare. Boy, was I mistaken. If a standard can be set by what is seen at Paul Horton's place, then the number is more like 1 in 15 - 20. I believe this is probably hereditary, as it is with humans.

Whatever the case, it is always better to "pinch" one of the embryos than risk losing the pregnancy, IMO.

Ruffian · Postby **Ruffian** » Sun Jan 09, 2005 7:14 am

I think it must be something to do with my mares but I would have to say 1 in every 3 covered produce two embryos- my vet always squeezes one- which is annoying because it is always the bigger one (for ease), So personnally I don't think twins ARE a rare occurance, yes to go through a whole pregnancy but not at conception as mine always are squeezed before 20 days.