Navicular - hereditary? and other q?'s

[Matreiya]

I just got a new broodmare on lease. Absolutely lovely mare and I am dying to breed her.

The owners had told me she was foot sore and the more I watch her, the more I cringe. She looks like it is very painful for her to move around and she does stab with her toe when she walks: her toes do look worn down. She seems inclined to trot only when she is attacking the lowest horse in the field. I have put the hoof testers on her and I cannot get her to flinch at all. She seems to have no problem standing for a while on the cross ties - when I hoof tested her, I decided to groom her so I could watch how she shifted her weight or what she would do. Her heels do look almost like they are cleft and smell a bit thrushy. I have started treating her for that. She lives out 24/7 and does move around her pasture..just slowly and it looks painful.

Some history - her dam was apparently put down because she had a history of throwing foals with OCD. There is no history of navicular on either sire's or dam's side. This mare (Abby) has had several foals, the oldest of which is 7 yo I believe. None of them have any foot or lamesness problems.

I do have a call into my farrier and, most likely, I will have my vet out this week. I didn't really want to get the vet out because I don't own her and didn't really want to put the money for this into her (breeding is expensive enough), but I just feel that if I don't find out, it would be irresponsible breeding.

So....is navicular hereditary? Does this mare sound like she has it? Would her foals be showing it by now? What else should I be asking?

thanks for any help! I'm just trying to do some research until I can get hold of my farrier and vet.

[Tom Stovall, CJF]

Matreiya in gray, deletia

So....is navicular hereditary?

A small foot under a big body is not as efficient in handling concussion as is a larger foot, so that particular conformation is thought to predispose horses to various forms of heel lameness. LT/LH (long toe, low heel) conformation is sometimes hereditary, places the navicular bone in abnormal compression, and may also be a precursor to navicular problems.

Considering the prevalance of these presentations and their link to heredity, the best answer to your question would probably be, "It depends." :)

[Thomas_Ride&Drive]

I'm not entirely convinced you are asking the right questions so will post more extensively from an article I've recently written for an English Forum on what you need to take into account and have highlighted specific considerations with regard to your questions relating to navicular and OCD etc:-

The first thing to consider is whether or not your mare is a suitable candidate for motherhood.

No matter what stallion she's put to, if she has hereditary unsoundness, serious conformation faults or very bad temperament you won't breed successful progeny.
And this in itself is all too often hard for the owner of a mare to judge objectively.

Regrettably a lot of owners can't see what is in front of them and think Flossy is the prettiest, sweetest and best horse in the world - even when she's been unsound for 2 years and looks like sh** and excuses like "she doesn't like being groomed because she's ticklish or sensitive!!" are frequently bandied.

How many times have you gone to a yard and looked at a horse or looked at a photo on the internet and thought "good grief", "poor devil", "that's scarey" -Or even just .... club footed, straight shoulders, cow hocked, bench knees, pigeon toes, calf-kneed, sickle hocked, etc etc. And others are genuinely saying "pretty pony, nice horse" . A lot of owners actually don't know what conformation a horse is supposed to have to meet its breed standard, do its job, be healthy and a lot can't look objectively at what they own.

Likewise folks say "its got fantastic blood lines" then when you enquire you discover its actually a cross breed and they only know the sire side or if its a pure bred and you know the breed very well, you think mmmm there's a smattering of good stallions there but some way back and the dam side is poor and weak.

Folks often think a purebred that comes with its papers and pedigree means its good. Heck everything has parentage! And even if the great great grand sire won the grand national so what! It doesn't mean its a good horse - heck there's another 63 horses in that pedigree alone to dilute (or compliment) anything he might have done.

Then again you have the mare whose breeding is absolutely unknown and whilst she may be average she's done nothing notable at all (not even as a pleasure horse) but the owner thinks it would be nice to have a baby and maybe even make some money. And even if owner is lucky and foal turns out o.k., sadly owner has never brought on a young horse and doesn't appreciate that nowadays folks don't buy green, unpapered horses for money so that you would make a profit and it takes a lot of money to get one trained to make it saleable.

The mare has considerably more influence on the foal than the stallion and rather than asking "what is this foal by?" they should be asking "what is this foal out of?"

If in doubt, remember you are embarking on a long term expensive project. Its possible to sell a foal that is of good quality and in demand but poor and mediocre foals ordinarily do not land up in good homes. Knowledgeable horseowners will NOT buy foals from poor quality or lame mares.

You also need to think about what you are trying to breed for because this would influence your decision and choice of stallion. And it might be a specific purpose sports or competition horse or just a good pleasure horse for yourself.

Once you've made that realistic assessment of your mare (or had someone else do it for you) you need to ensure she is in excellent health. Don't forget that the process of carrying a foal to term places a burden on the mare and her health needs to be good. Again too often a lame horse is put in foal and guess what - laminitis onsets and then it founders because of the extra stress and weight etc. If the mare isn't fit and healthy, she's not IMO a suitable candidate for motherhood.

Then having ticked all the boxes, you need to turn to the stallion and ensure you know that NO stallion will compensate for any serious defects, but you need to ensure that the choice of stallion does not exaserbate any such problems.

There is no such thing as a perfect horse and if she is long in the back you might want to find a suitable stallion who is short coupled and hope (and it is just hope because foal could take on from the mare's genetics) that this quality might be improved.

Then having decided what you want, you need to find a proven stallion and whilst all stallions have to start somewhere I'd strongly advice a novice breeder not to use an unproven stallion on his first season. In addition to proving he is fertile I'd also want to know what his ability, temperament, performance record etc are like. If he's got fantastic blood lines and you're breeding a pure breed you might want to take the risk of using a young unproven stallion - but if not, then don't do it.

Then go and see the stallion - even if you intend to AI the mare - go and check out its conformation and temperament.

Finally before you make the decision to take your mare to the stallion remember that whilst hopefully everything will be fine, that mares do sometimes die at stud or in foaling. These things happen even to healthy mares when things are very well managed. When I had a stud farm we lost 2 mares with a ruptured uteris. Now this was a small % in terms of the number of mares we had coming in, but to the owners (and to us) its a devestating experience to lose a mare because of something you have voluntarily subjected it to. And we very occasionally had problems with foaling and have lost mares and foals and sometimes both. I have a horse, bred from my own much loved extremely fit and healthy competition mare that died foaling, and who had to be hand reared.

And again BEFORE you take her to the stallion, ensure you know everything about feeding and managing her whilst she's in foal and going through the process of foaling and line your vet up to ensure he's there to support you if needed.

And finally you need to think about how you're going to sell the foal and at what stage (unless you are keeping it for yourself). Its often not easy nor profitable to sell young horses nowadays. A lot of folks want them backed and schooled and proven. And a lot that take foals have no experience bringing them on at all. So ask yourself "do you care where it ends up?", "have you got a prospective owner lined up?", "are you confident you can sell it for what you want?", "if you can't sell it what are you going to do with it? Do you have a contingency plan B?"
Its known to be multi-factorial and feed plays a big part.

I don't understand the comments in relation to her Dam and OCD. Rather than OCD being genetic in the sense that its an inherited defect with a direct mode of transmission, its something that is predisposed in breeds with a lot of growing to do. So in both dogs and horses, in the large breeds. Its not an inherited condition, its merely predisposed in large breed with a lot of rapid growing to do. So welsh section A's, shetland ponies rarely get it and cleveland bays, shires, warmbloods more commonly can and do.

With regard to navicular - it really depends on what functional anatomical defects/changes have been identified via x ray etc. Truth is though that a lot of navicular cases is never tied down to a specific conditional with a single cause and rather its merely used to describe the syndrome of pain in the navicular area and arising from a variety of pathological changes.

There is evidence that its multi-factorial and largely related to the conformation of the foot and its particularly predisposed with a higher incidence rate in Quarter Horses. Horses with all types of foot conformation can develop it, but its more common if they've got poor foot balance: long toes, and low, collapsed heels and also upright narrow feet.

Horses with navicular tend to place the foot to the ground slighly toe first and particularly seen when the horse is on a hard flat surface. The stride is slightly shorted and lameness may be accentuated by flexion. There may be stronger digital arterial pulses and its rare that hoof testers cause pain. You need to get the horse de-sensitised though as part of diagnosis and also x rays.

Finally though you never asked ;) if it were my mare I wouldn't be breeding from it - too many risks and negatives. If you can get her properly diagnosed and her lameness sorted out first and if she's exceptional breeding lines and conformation and proven quality then consider it. But it sounds to me like you've a lot to get sorted and so light years away from being in that situation.

[Matreiya]

Thank you for the replies.

As to breeding, I am a small breeder, and while relatively new to it, I do have a good amount of knowledge. Both my broodies have very good bloodlines and I am very careful in choosing stallions for them.

As for the mare in question, she has exceptional bloodlines and actually has quite nice conformation. Her feet LOOK like a good size for her body and good angles. Obviously, I need my farrier to really tell me what's what, but that's how it looks to me. The foal resulting out of this mare (I only have her for a year) would be for me. Not for sale. The stallion I want to use is a good match for her conformationally. He has a wonderful temperament from what I am told (he's in Sweden, can't go see him) and she has one of the best temperaments I've run across. Further, all of the mare's foals have gone premium at their inspections and her eldest is scoring in the 70's in First & Second level Dressage.

Despite her foals' successes, I did not breed them and after watching her move, I am reconsidering breeding her myself. Obviously, I am not going into this willy-nilly. Her owners, however, never had any diagnostics to find out why she was lame and I did not know she was this lame when I picked her up. I was told she just had some foot soreness. *sigh* I'm trying to be diligent. I am going to call the vet tomorrow and I do have a call into my farrier.