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Post by cddexter on Oct 5, 2012 22:13:26 GMT -5
;D ;D ;D ;D ;D ;D ;D GOT ME!!!! ;D ;D ;D ;D ;D Well, I'm still inclined to think dwarf. But, this is why it's not an exact 'science'. Go and check out Brightlea Benjamin on the ADCA online pedigree. His photo makes him look like a nice dwarf. he's actually not, just has exceptional length and not much height. Sometimes it's really hard to tell. I'm working 5-12 for the next six days , so won't be back till the afternoon. I'll give you the last formal instalment, and the misc stuff then. Then, YOU can go out and come back and tell me. ;D Sure is well trained! cheers, c.
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Gorignak
member
Farm Facebook page is now up. Stop by and say HI !!
Posts: 569
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Post by Gorignak on Oct 6, 2012 10:27:03 GMT -5
Thanks Carol....keen grasp of the obvious. It would seem that if "normal" organs were compressed in an "abnormal", or "defective" framework, that the function of those organs might be affected...... both input ( nutrients in) and the output (calf/milk out)
Also, if anyone believes that repeated selection in a limited genetic pool yields only the sought for results.....well, try a little Stephen J. Gould. A little added, a little subtracted.
My point is that while the focus is the bone length, it is a symphony of alterations. I am betting that there are other noticeable characteristics...that is unavoidable.
Please add any links to scholarly papers on the subject. I have found a couple.....
NICE OX Olga....ENVIABLE training on the hitchin' video. Nice having one with Reverse. Compliments to the trainer....Smooooooth.
Genotype for Oz came back in 5 days from Davis. Waiting on the rest
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Post by cddexter on Oct 6, 2012 20:26:16 GMT -5
I've added the rest of the ID.
You might like to check out the photos that Mike and Hans posted to do some comparisons, and see if you can 'see' the differences I mentioned.
It doesn't matter where you choose to test (and I'm sorry this thread had turned into yet still another plug for Davis). What matters is that testing is done.
It doesn't matter which type you choose to breed. What matters is that you understand what you are doing, and do so knowingly--and with honesty--both to others, and to yourself. There is no way the aborted calf shown on the ADCA website Chondro article is the result oif a benign condition. cheers, c.
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Post by rezzfullacres on Oct 6, 2012 20:42:51 GMT -5
Thank you for taking the time and effort to post this.....thank you very much...
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Post by lakeportfarms on Oct 7, 2012 5:49:48 GMT -5
Carol,
Could you weigh in on your thoughts about severe carrier vs. proportionate carriers, and their likelihood to throw carrier calves? I think you could classify our bull Mike as a severe carrier, and he throws significantly more than 50% carrier calves.
As near as I can figure we've had about 65 calves out of him with slightly under 54 being carriers. Not just in Dexters either, prior to bumping up our Dexter numbers we've had Angus, Highland, Hereford, and Jerseys all bred to Mike and clearly affected with chondrodysplasia, though we didn't test them.
Is the test even capable of testing for the gene in other breeds?
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Post by cddexter on Oct 7, 2012 6:56:27 GMT -5
hans, the boffins say it's a crap shoot, just like a coin toss. So, eventually the numbers should even out. You don't say if any of your Dexter cows are dwarf, too.
30 yearsa ago, I also wondered about the expressed severity of the condition and thought I'd seen SIX different types of Dexter. As I understand it, the mutation is what it is, and to date no one knows why there is a variation in that expression.
If the not pure Dexter receives its dwarfing gene from a Dexter, then yes, it's possible to test for the condition in animals that are from other breed genetics.
Gaaah, it's five to five AM, and Im off to work. talk later, cheers, c.
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Post by marion on Oct 7, 2012 13:54:28 GMT -5
Gene, do you have pictures of your first two Dexters, who turned out to be dwarfs? As you know, the person famous for developing small non-dwarfs, long before a DNA test was available was Beryl Rutherford in England..Woodmagic herd. Several breeders imported Woodmagic animals into Canada, but not long after, Doris and Marshall Crowe having started out with an all non-carrier herd, bought heifers from the US Klein of Hydrif herd that were carriers and bred them to the Woodmagic animals. (I can only guess they didn't realize the value of retaining the small but non-carrier status??) So after that introduction, having Woodmagic/Cranworth in the pedigree was no guarantee of freedom from chondrodysplasia. It is possible to breed small-in-stature animals with pleasing conformation that do not carry the chondro gene. That is my preference..breeding animals with no genetic defect; never having to make sire/dam decisions based on the avoidance of bulldog calves, and obviating the need for endless testing. From your post, it sounds as if you do not believe in the existence of small, deep-bodied non-carriers. It is true that in the past some breeders used the 'small proportional' to sell animals, that were later found to be chondro carriers. Maybe some still do (I know of one large herd recently dispersed, where they insisted for years that those "little chunky" ones were not dwarves. Buyers in recent years largely thanks to the internet, are better informed.)
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Post by cddexter on Oct 7, 2012 16:37:44 GMT -5
Gene, where do I start? Producing statements as absolutes rather than opinion is going to get you in trouble one day. A lot of your posts are too much fun to criticize, but there ae limits.
"If you were breeding carriers to carriers, then you would expect "that 67% of your live calves would be short legged and 33% long, even if your bull's semen contained exactly 50/50 male and female sperm."
Gene, PLEASE DON'T DO THIS. You're comparing apples to oranges, and for those who don't get it, it's really confusing. There is NO relationship.
Since I coined 'proportionate' in 1987, I figure I have the right to disagree with your take on it. It was mainly to get past the stigma of the eaten or dumped rangy 'longlegs' that were produced because 30 years ago there was little done in the way of selection othr than to use chondro to reduce the size. Mark Davis told me he used the bull with the longest legs to avoid bulldogs. See what I mean?
"While the old methods were in use Beryl Rutherford, in England, was one of a few people who even guessed correctly that bulldog calves were the result of breeding two short legged Dexters together. Nobody in the US or Canada had it right.
Sorry, that's absolute poppycock (well, it is corny, but not popped or covered in caramel). People knew 200 years ago that you got bulldogs from two carriers. Nothing's changed. You might get the odd owner who doesn't have a clue, but that's the exception.
Etc. cheers, c.
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Post by cddexter on Oct 7, 2012 23:05:15 GMT -5
gene. Perhaps it's your sentence structure?
You were talking about some animals having a higher percentage of male sperm vs. female sperm, then said this could be true of chondro, too. Since this was in reference to someone getting a higher percentage of carriers, would one not think you were still on the same topic? The very next sentence combines chondro percentages with sex percentages, as though they were connected. What you said is true if you ignore the bulldogs, so I guess it's not really true after all, and it's out of context, which for those whose knowledge is shakey or limited, is very confusing.
No one in Dexterdom used the term 'proportionate' when refering to either type until I applied it to non-dwarfs in 1987, in a paper I wrote for the ADCA. Within one month or so, it was picked up by other breeders to refer to their non-dwarfs, and used in their sales advertising. Within six months, the dwarf breeders were using it to describe their more proportionate (less clunky or severely affected) dwarfs. It's now common parlance used to describe both types all over the world. Beryl had the same problem: she coined the term 'medium legged' to describe her non-dwarf, shorter cannon boned Woodmagic animals. It didn't take long for the dwarf breeders to borrow it to describe their more proportionate (less clunky or severely affected) dwarfs.
The (English) Agricultural Cyclopedia, 1911 Edition, in which the author states that in 19th Century Ireland breeders had already learned through experience that "they prefered to mate the Kerry with the Dexter, for when two Dexters are mated, they sometimes throw misshape calves", and according to Wm. Hooper of Co. Dublin, writing in 1898, of earlier times: "there is abundant testimoney in support of the assertion that Dexters are apt to throw misshapen deformed calves --'monsters' the Kerry farms term them".
Anything else? Cheers, c.
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Post by lakeportfarms on Oct 8, 2012 8:31:01 GMT -5
I didn't mean to start a fight...when I said "proportionate", I meant one that didn't meet either extreme either long or short. I've seen, and own, some extremely long legged (but small body) Dexters (I guess that would be the "rangy longleg" type), and we also have some extremely short legged bulls and cows where there is absolutely no question on their status. We also have several that without the test it would have been difficult to determine their status. Perhaps we could put our heads together and come up with some simple phraseology that would apply to the 6 Dexter types that Carol mentioned that we could use here? Carol, correct me if I'm wrong, but doesn't "severely affected" usually refer to bulldogs with both affected genes? Those wouldn't exist in a herd, at least alive, that is why I used the word "severe carrier", meaning only one affected gene, but with exaggerated characteristics (perhaps a better description) . Perhaps that could be a term...exaggerated chondro, normal chondro, slight chondro/ then slight non chondro, normal non chondro, exaggerated non chondro. Kind of clunky, isn't it? Maybe we could act like teenagers (some would say we do) and refer to it as ec, nc, sc, etc... Could it be our environment that has caused this? I suppose given that they are pastured in an apple orchard there is a distinct possibility that that could contribute to our results. They eat apples, and like to chew off the ends of the branches. My theory has been that with a more exaggerated chondro appearance, that the possibility exists that it is more likely to dominate the genetics of the progeny, just as other traits such as udders, feet, etc. are passed on. At least that seems to be our experience so far. I'm just wondering if there has been any other similar experience here. By the way, this has all been carrier (bull) to non-carrier results for us, and as I said not necessarily with both being Dexters. Though we've had a few of our Dexters for some time (6 years now), we had not transferred the registrations, joined the ADCA, or significantly expanded our Dexter herd until the last couple of years after we sold off some of our other breeds to make room. We purchased Mike because we got tired of arranging AI on the non-Dexters, and didn't want a hulking 2000 lb Angus or Hereford bull on the property. Almost everything we got out of him from these other breeds was short legged. We have had a few that must have combined with some hidden dwarf gene from the Angus and Hereford genetics that were incredibly small, sort of like Gene's Bucky.
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Post by coyotemoon on Oct 8, 2012 16:02:41 GMT -5
You know, I've kind of come into the habit of taking a seasick pill and bringing a shovel in with me when I intend to look at this forum. It kind of makes my head spin, and I have to do a lot of digging to get to the pearls. Those pearls make it all worth it.
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Post by cddexter on Oct 8, 2012 16:16:57 GMT -5
Hi lakeport. sorry about that, my fault. Speaking of dwarfs, I was trying to distinguish between the really tiny, really ugly clunky ones and the more normal looking ones, and didn't think about technical terms. You are right. The six phenotypes I thought I could separate the two genotypes into were based on seeing approx. 80% of all the Dexters in England, in 1986/7 (and taking over 1,500 photos to prove it). I divided them into 1. Non-carrier from two carriers: tall, spindly, no body depth height roughly 36 to 42 2. Non-carrier from two nons, OR a non x a carrier: square or rectangular profile, height 39-44, some to 48 3. Non-carrier from two nons, OR a non x a carrier: rectangular profile cows 39 -41, bulls 42-44 Woodmagic type 4. Carrier from two carriers, OR a non x a carrier: relatively proportionate with choppy stride and small legs, height 38 - 44, some to 47 5. Carrier from two carriers, OR a non x a carrier: big head, no neck, verys hort choppy stride, often poor body lenth, height 36-42 6. bulldog from two carriers. That was my first exposure to dwarfs, never seen any before. Knew diddly squat about chondro or dwarfs, or Dexters in general either for that matter. I sure had a short learning curve I put my theory to some of the leading owners of the day, includig two that had a genetics background, and was told absolutely that while it may look like different types, they were all the same. There was no guarantee that two uglies would produce an ugly, or that a nice would produce nice. Results were all over the map. I took them at their word. Meanwhile, Leo Curran in Dublin wrote an article for the Rare Breeds magazine, The Ark. He's a plant geneticist with the Unviersity in Dublin, involved with the Irish movement to protect endangered species, and the author of the recent book on Kerries and Dexters. He thought he saw five types. So, I visited with him at the UofD and we talked at length about 'our' findings. he assured me MY six were NOT the same as HIS five. In fact he was quite put out I'd think I'd come up with a similar result. His five are 1. Kerry 1 : 16 2. low grade achondroplast or 'sneem' Kerry 3 : 16 3, intermediate grade achondroplast 8 : 16 4, exhibition grade achondroplast 2: 16 5. bulldog 2 : 16 He gave an expanded paper based on this article at the '98 Congress. Even though he's a well known and respected geneticist, his theory proved to be incorrect. So, while it does appear that there are distinct types within the dwarf population, there is no evidence that 'like begats like'. Cheers, c.
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Post by legendrockranch on Oct 8, 2012 18:16:48 GMT -5
I think the term "severe carrier" would aptly apply to an animal that is "greater than average or expected".
I use the term myself. On several occasions I have taken folks that come to visit my herd (all non-carriers of chondro) over to my neighbors house. He has all colors of Dexters plus polled, dehorned and horned, chondro carriers and possibly PHA carriers. It's good for them to see and learn about what our breed consists of.
He definitely has some chondro carriers that show a different degree of the gene. In fact he has one that is pregnant and due to calve at any time. I wonder how that calf will be able to nurse because her udder almost touches the ground. To me that's severe.
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Post by hollydzie on Oct 8, 2012 19:02:51 GMT -5
coyotemoon ~ you took the words right out of my mouth. Well put.
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Post by cddexter on Oct 9, 2012 17:23:08 GMT -5
Let's get back on track, here.
Anyone interested in posting a photo, and letting the rest of us guess if it's a dwarf or a non, and say why? I'm not looking at the breeding quality here, just symptoms of one type or the other.
OR, anyone interested in posting photos and saying what trait clued them in that the animal was which type?
Cheers, c.
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