Re: [blackbelly] Horn Genetics question
Here is an excellent primer on the genetics of horns in our sheep. It is a very simplistic model and works ONLY if none of the ewes in a flock have horns. It also assumes there is only one gene for horns. We now know that is not the case; there also is a gene for scurs. It was written by Dave Thomas, Professor of Sheep Genetics and Management, University of Wisconsin-Madison and is printed here with his permission: _ Inheritance of horns is not as simple as the genetic textbooks make it seem. It is complicated by the fact that inheritance can be different in males and females and in different breeds. However, generally speaking, horns are recessive and polledness is dominant. If I let H = the dominant gene for polledness and h = the recessive gene for horns, the following situations can result: HH = animal has 2 polled genes and is polled Hh = animal has 1 polled and 1 horn gene and is polled because the polled gene is dominant hh = animal has 2 horn genes and is horned If you purchase a polled ram, he can be HH or Hh. If he is HH, all his progeny will be polled because all the progeny will have at least one H gene. If he is Hh, he can produce polled or horned offspring depending upon the type of ewes he is mated to. Blackbelly ewes are usually polled, but they can still carry the horn gene. They just don't express the horn gene. Mating a polled ram that is a carrier of the horn gene (Hh) to different types of ewes will give you the following types of progeny: Ram x Ewe = Progeny Hh x HH = 50% HH, 50% Hh = all lambs polled Hh x Hh = 25% HH (all polled), 50% Hh (all polled), 25% hh (males horned, females polled) Hh x hh = 50% Hh (all polled), 50% hh (males horned, females polled) If the polled ram has a horned parent, then the ram is Hh. If the polled ram has produced lambs and at least one was horned, then the ram is Hh. If the ram has been mated to several ewes in a flock where horned males are found and he has never produced a horned lamb, then you have some confidence that he is HH, however, there is still a chance that he is Hh. Carol ___ This message is from the blackbelly mailing list Visit the list's homepage at blackbelly@lists.blackbellysheep.info http://lists.blackbellysheep.info/listinfo.cgi/blackbelly-blackbellysheep.info
Re: [blackbelly] Horn Genetics question
Basic genetics would say "yes" as the liklihood of getting all the genetics necessary to produce horns would be greater. Terry --- David Kellough <[EMAIL PROTECTED]> wrote: > If a horned ewe and a horned ram produce a ewe lamb, > is the odds much > greater the ewe lamb will have horns? > just wondering > David Kellough > ___ This message is from the blackbelly mailing list Visit the list's homepage at blackbelly@lists.blackbellysheep.info http://lists.blackbellysheep.info/listinfo.cgi/blackbelly-blackbellysheep.info
Re: [blackbelly] Horn Genetics question
If a horned ewe and a horned ram produce a ewe lamb, is the odds much greater the ewe lamb will have horns? just wondering David Kellough - Original Message - From: "hlang" <[EMAIL PROTECTED]> To: Sent: Monday, January 16, 2006 1:55 PM Subject: Re: [blackbelly] Horn Genetics question > In beef and sheep, there are bulls and rams which are dominate polled.'You > can use them on what ever kind of horned ewe or cow and never any horn for > many generation. > I work horned cows, up to 60 and use polled bulls, never one horn to see > if > selected. > Same for SA ram import, on what ever Barbados or horned ewe I use, > offspring > polled. > > Because for many years and with big number of livestock, the selected.The > genetics are clean and that kind of genetics is so powerful, that the > horns > are matched out. > > But in US hair sheep Dorper or what ever, the genepool is way too small. > And instead to select first for healthy and strong animals, the genepool > get > cut down by funny regulations. > Regards Helmut > - Original Message - > From: "Carol J. Elkins" <[EMAIL PROTECTED]> > To: > Sent: Monday, January 16, 2006 9:08 AM > Subject: Re: [blackbelly] Horn Genetics question > > >> Terry, the reason you can't find the genetic research is because it >> doesn't >> exist. I've talked to several sheep geneticists the past couple of years >> and learned that horn genetics are simply not understood and are not >> being >> well researched because there is no funding to do so. Therefore, it is >> our >> responsibility as breeders to keep excellent records, develop our own >> hypotheses, and test them as carefully as possible. The conclusions we >> derive will, in the absence of academic research, hopefully provide >> information that will be useful to others. >> >> Carol >> >> At 01:41 PM 1/14/2006 -0800, you wrote: >>> It is stated that if a polled ewe has a horned sire, >>>she is considered American Blackbelly. the question is >>>this-- if the MATERNAL GRANDSIRE is horned, ( the sire >>>is polled) what are the chances of passing that along? >>>Some people would call it "generation skipping" I am >>>thinking more along the lines-- are horn genetics like >>>hemophilia? Passed through females only, so they can >>>be passed on and not show for several breedings? or >>>must a "doubling up" occur? I am not finding the kind >>>of genetic research I am looking for on this!!! >> >> Carol Elkins >> Critterhaven--Registered Barbados Blackbelly Hair Sheep >> (no shear, no dock, no fuss) >> Pueblo, Colorado >> http://www.critterhaven.biz >> T-shirts, mugs, caps, and more at the >> Barbados Blackbelly Online Store http://www.cafepress.com/blackbellysheep >> >> ___ >> This message is from the blackbelly mailing list >> Visit the list's homepage at blackbelly@lists.blackbellysheep.info >> http://lists.blackbellysheep.info/listinfo.cgi/blackbelly-blackbellysheep.info >> >> >> -- >> No virus found in this incoming message. >> Checked by AVG Free Edition. >> Version: 7.1.371 / Virus Database: 267.14.19/231 - Release Date: >> 16/01/2006 >> >> > > ___ > This message is from the blackbelly mailing list > Visit the list's homepage at blackbelly@lists.blackbellysheep.info > http://lists.blackbellysheep.info/listinfo.cgi/blackbelly-blackbellysheep.info > ___ This message is from the blackbelly mailing list Visit the list's homepage at blackbelly@lists.blackbellysheep.info http://lists.blackbellysheep.info/listinfo.cgi/blackbelly-blackbellysheep.info
Re: [blackbelly] Horn Genetics question
In beef and sheep, there are bulls and rams which are dominate polled.'You can use them on what ever kind of horned ewe or cow and never any horn for many generation. I work horned cows, up to 60 and use polled bulls, never one horn to see if selected. Same for SA ram import, on what ever Barbados or horned ewe I use, offspring polled. Because for many years and with big number of livestock, the selected.The genetics are clean and that kind of genetics is so powerful, that the horns are matched out. But in US hair sheep Dorper or what ever, the genepool is way too small. And instead to select first for healthy and strong animals, the genepool get cut down by funny regulations. Regards Helmut - Original Message - From: "Carol J. Elkins" <[EMAIL PROTECTED]> To: Sent: Monday, January 16, 2006 9:08 AM Subject: Re: [blackbelly] Horn Genetics question > Terry, the reason you can't find the genetic research is because it > doesn't > exist. I've talked to several sheep geneticists the past couple of years > and learned that horn genetics are simply not understood and are not being > well researched because there is no funding to do so. Therefore, it is our > responsibility as breeders to keep excellent records, develop our own > hypotheses, and test them as carefully as possible. The conclusions we > derive will, in the absence of academic research, hopefully provide > information that will be useful to others. > > Carol > > At 01:41 PM 1/14/2006 -0800, you wrote: >> It is stated that if a polled ewe has a horned sire, >>she is considered American Blackbelly. the question is >>this-- if the MATERNAL GRANDSIRE is horned, ( the sire >>is polled) what are the chances of passing that along? >>Some people would call it "generation skipping" I am >>thinking more along the lines-- are horn genetics like >>hemophilia? Passed through females only, so they can >>be passed on and not show for several breedings? or >>must a "doubling up" occur? I am not finding the kind >>of genetic research I am looking for on this!!! > > Carol Elkins > Critterhaven--Registered Barbados Blackbelly Hair Sheep > (no shear, no dock, no fuss) > Pueblo, Colorado > http://www.critterhaven.biz > T-shirts, mugs, caps, and more at the > Barbados Blackbelly Online Store http://www.cafepress.com/blackbellysheep > > ___ > This message is from the blackbelly mailing list > Visit the list's homepage at blackbelly@lists.blackbellysheep.info > http://lists.blackbellysheep.info/listinfo.cgi/blackbelly-blackbellysheep.info > > > -- > No virus found in this incoming message. > Checked by AVG Free Edition. > Version: 7.1.371 / Virus Database: 267.14.19/231 - Release Date: > 16/01/2006 > > ___ This message is from the blackbelly mailing list Visit the list's homepage at blackbelly@lists.blackbellysheep.info http://lists.blackbellysheep.info/listinfo.cgi/blackbelly-blackbellysheep.info
Re: [blackbelly] Horn Genetics question
Terry, the reason you can't find the genetic research is because it doesn't exist. I've talked to several sheep geneticists the past couple of years and learned that horn genetics are simply not understood and are not being well researched because there is no funding to do so. Therefore, it is our responsibility as breeders to keep excellent records, develop our own hypotheses, and test them as carefully as possible. The conclusions we derive will, in the absence of academic research, hopefully provide information that will be useful to others. Carol At 01:41 PM 1/14/2006 -0800, you wrote: > It is stated that if a polled ewe has a horned sire, >she is considered American Blackbelly. the question is >this-- if the MATERNAL GRANDSIRE is horned, ( the sire >is polled) what are the chances of passing that along? >Some people would call it "generation skipping" I am >thinking more along the lines-- are horn genetics like >hemophilia? Passed through females only, so they can >be passed on and not show for several breedings? or >must a "doubling up" occur? I am not finding the kind >of genetic research I am looking for on this!!! Carol Elkins Critterhaven--Registered Barbados Blackbelly Hair Sheep (no shear, no dock, no fuss) Pueblo, Colorado http://www.critterhaven.biz T-shirts, mugs, caps, and more at the Barbados Blackbelly Online Store http://www.cafepress.com/blackbellysheep ___ This message is from the blackbelly mailing list Visit the list's homepage at blackbelly@lists.blackbellysheep.info http://lists.blackbellysheep.info/listinfo.cgi/blackbelly-blackbellysheep.info
[blackbelly] Horn Genetics question
I was looking at the paperwork that came with my BBSAI membership today ( gee-- I am Certified!!) and am asking this out of curiousity-- It is stated that if a polled ewe has a horned sire, she is considered American Blackbelly. the question is this-- if the MATERNAL GRANDSIRE is horned, ( the sire is polled) what are the chances of passing that along? Some people would call it "generation skipping" I am thinking more along the lines-- are horn genetics like hemophilia? Passed through females only, so they can be passed on and not show for several breedings? or must a "doubling up" occur? I am not finding the kind of genetic research I am looking for on this!!! Terry W ___ This message is from the blackbelly mailing list Visit the list's homepage at blackbelly@lists.blackbellysheep.info http://lists.blackbellysheep.info/listinfo.cgi/blackbelly-blackbellysheep.info
