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RE: [SPAM] Re: [RC] Old mares and their foals - heidiHere are three of the reasons why I presumed the get of an older mare were more likely to have problems. In general, old mares are less active and thus stimulate the foal in utero less. Their blood's ability to deliver nutrients and oxygen declines. Loss of muscle tone causes the anus to sink in a bit and fecal matter can more easily enter the urinary and vaginal tract.* A lot of the activity of older mares depends on how they are housed and how healthy they are. Healthy older mares out on pasture are every bit as active as their younger counterparts, in my experience. Clearly there is more opportunity for an older mare to have sustained injury or to have achieved breakdown due to poor conformation--but that doesn't affect the healthy, sound older mares. Additionally, it isn't the ability of the blood to deliver nutrients--it is the inability of a scarred endometrium and a possibly thickened placenta that gives rise to such problems. And again, while these things do occur more often in older mares, one cannot simply make a blanket statement, since many older mares have no such difficulties at all. With regard to a sunken anus--that usually prevents mares from getting pregnant or from carrying to term. If the mare achieves pregnancy and the fecal material sets up an inflammation of the cervix, then yes, you can have trouble. But again, for the older mares who have NOT lost their perineal integrity and for those who have but are given the benefit of a Casslicks repair, this is also a non-issue in the future usefulness of the foal. The following apply to humans over 35 or 40 (why not a horse whose roughly equivalent to a 65 year old human?) and while the reproductive physiology of humans and horses is vastly different, they are both mammals and all mammals AGE. The quality of ova declines with age**; as humans age they have progressively more fetuses with chromosomal abnormalities***. Indeed they do. But the majority of the embryos conceived that have these problems are lost sometime during the pregnancy. Very few go to term. So again, once there is a live foal on the ground, this isn't something I'd hold against an old mare. It CAN increase the rate of embryonic death, though, which is frustrating to the breeder. BTW, in searching for information to "back the statement", I came across this interesting tidbit: http://sheknows.com/about/look/1022.htm Men over age 40 were twice as likely to have a Down syndrome child than men less than 20 years old," notes Dr Fisch. So perhaps I should amend my statement to include OLD stallions :) Indeed, older males of all species are more apt to have chromosomal abnormalities. It isn't quite the same issue as in the females, where the ova are more prone to mutation, but the problem does exist. Which is why I'm not going to rebreed the 30-year-old stallion to the 24-year-old mare, in which we DID get an early embryonic death last time we tried it. She will go to a young stallion, and he is having a grand time settling his younger mares. Heidi =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Ridecamp is a service of Endurance Net, http://www.endurance.net. Information, Policy, Disclaimer: http://www.endurance.net/Ridecamp Subscribe/Unsubscribe http://www.endurance.net/ridecamp/logon.asp Ride Long and Ride Safe!! =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
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