The Accidental Smallholder Forum
Livestock => Sheep => Topic started by: Slimjim on November 24, 2014, 11:35:09 am
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Hi, I have a new Hampshire Down tup for my small mixed flock ( 2x Jacob, 2x Badger Face, 1x Lleyn, 1x Greyface Dartmoor) of ewes this year. Almost 3 years old, he has not worked before, so there is no productivity history for him.
I was told he was a triplet, so I wondered if that would have any bearing on the prolificacy of the ewes he tups. Or is it more likely to influence the prolificacy of his daughter ewe lambs he sires when they start breeding? Or both perhaps??!
Many thanks.
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I don't think it can have any influence on the number of lambs your ewes will have; that's determined by how many eggs they shed, implant and carry to full term. Although, obviously, if the ram is sub fertile (nothing to do with him being a triplet) then he WILL have an influence.
Prolificacy is hereditary though from both male and female sides so the fact that he's a triplet should in theory mean that his daughters will be more likely to have multiple births. But of course that's all statistics and whether they do or not will depend on many other factors too :)
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I agree it is likely to affect the prolificacy of his daughters.
However, if his dad had and also he has super-fertile super-active sperm then it could conceivably (intentional pun) be that he is more likely to sire triplets too. Either more likely to fertilise multiple eggs if the female produces them, and/or more likely to get coincident multiple fertilisations of one egg - so identical twins. Plus perhaps the eggs are more healthy / likely to implant and go to term - all sorts of factors that could be hereditary.
I wonder if anyone has done any quantitative research on this... :thinking:
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I wonder if anyone has done any quantitative research on this... :thinking:
Probably not, as most farmers don't really want triplets, unless they know the ewe is capable of rearing them
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Your ram will have no effect on your ewes prolificacy as everyone says it the number of eggs shed by the ewe so long as the ram is fertile . All studies done say that heritability of reproductive traits is very low , you need to know more than he is a triplet , mother may have had singles every year but one ( if the mother had triplets every year , was a triplet herself and her sire was a triplet and so on then you may influence the genes )
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Your ram will have no effect on your ewes prolificacy as everyone says it the number of eggs shed by the ewe so long as the ram is fertile . All studies done say that heritability of reproductive traits is very low , you need to know more than he is a triplet , mother may have had singles every year but one ( if the mother had triplets every year , was a triplet herself and her sire was a triplet and so on then you may influence the genes )
Hence breeders use of BLUP analysis to predict these traits
Most terminal traits have a heritable value of 0.3+
Most maternal traits have a heritable value of about 0.03
FEC is about 0.3 too
values vary from population to population
BLUP enables us to predict these traits in a lamb with fair accuracy----my lambs EBVs have accuracies of about 65% for maternal traits and 80% for terminal traits
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Well thanks for all that. I asked the question because when I challenged a post last year that suggested the ram could influence the number of lambs per ewe, I was shouted down and clearly there are people out there that believed it could.
Tim I'm sorry, but your contribution is lost on me. I just know what I need to know for the welfare of my little hobby flock, but there is a big audience out there, so thanks.