The Accidental Smallholder Forum

Livestock => Cattle => Topic started by: Loobylou on August 02, 2015, 08:30:11 am

Title: Twin calves
Post by: Loobylou on August 02, 2015, 08:30:11 am
So if a cow has twins and she has one of each sex, is the female always a freemartin? Not that I've got. Just wanted to know
Title: Re: Twin calves
Post by: devonlady on August 02, 2015, 09:11:06 am
Not always but generally.
Title: Re: Twin calves
Post by: Loobylou on August 02, 2015, 09:21:04 am
So How would you know if they were freemartins? Would you test at a certain age?
Title: Re: Twin calves
Post by: landroverroy on August 02, 2015, 10:05:01 am
 Realistically you wouldn't bother testing, just fatten it for meat.
Title: Re: Twin calves
Post by: Loobylou on August 02, 2015, 10:06:14 am
Ok that's fine, thanks
Title: Re: Twin calves
Post by: SallyintNorth on August 02, 2015, 05:25:07 pm
Realistically you wouldn't bother testing, just fatten it for meat.

Agree.

But treat and handle her like a heifer, because she may be fertile - so she may come a-bulling and if she's with entire males, could get herself pregnant ;)
Title: Re: Twin calves
Post by: Kimbo on August 02, 2015, 06:15:44 pm
Realistically you wouldn't bother testing, just fatten it for meat.

Agree.

But treat and handle her like a heifer, because she may be fertile - so she may come a-bulling and if she's with entire males, could get herself pregnant ;)

 :o  well that is one beast you would certainly want to keep!
Title: Re: Twin calves
Post by: SallyintNorth on August 03, 2015, 12:47:03 pm

Some people think that a freemartin won't be a breeder, and therefore they can safely run her with uncastrated males and/or the bull.  I was simply making the point that you shouldn't assume that she won't be a breeder, so she could come a-bulling before you would want any heifer bulled, and if you don't treat her like any other heifer, she could be running with males you would not want fathering calves, giving you a teenage pregnancy with a non-ideal father.

Title: Re: Twin calves
Post by: waterbuffalofarmer on August 03, 2015, 01:33:06 pm
Am I correct in assuming that the heifer, IE freemartin, may not be infertile? I was told that almost all of them are ???
Title: Re: Twin calves
Post by: landroverroy on August 03, 2015, 03:55:43 pm
 No.
The assumption is that a freemartin is infertile because of the male hormones from her twin brother that entered her bloodstream before she was born.  
However - many things in nature are not absolutely guaranteed. Therefore, given the remote (but unlikely)  possibility that the heifer could get pregnant, it's better to play on the safe side.
Title: Re: Twin calves
Post by: twizzel on August 12, 2015, 08:43:30 am
One of the cows in my partners herd is a twin, she's just had her 2nd calf  :)
Title: Re: Twin calves
Post by: Backinwellies on August 12, 2015, 03:06:20 pm
The big issue here really is no one would want to feed a cow for 2 years to find out its not fertile ... So practically you would assume a female twin of a mixed se Ed set of twins is infertile and fatten for meat.
Title: Re: Twin calves
Post by: waterbuffalofarmer on August 12, 2015, 03:43:17 pm
You dont necessarily have to wait two years for her to bull, some of my heifers have come bulling at one year. Thankfully i dont run them with the rest of the herd and bulls.  :relief:
Title: Re: Twin calves
Post by: farmvet on August 12, 2015, 10:37:07 pm
Some non breeders can be detected by vet exam eg short vagina, small/absent ovaries, but others may appear normal on scanning/ palpation but never breed due to eg absent oviducts. It is quite routine in this area to check any brought in cattle before bulling usually at the same time as bvd screening. You cant always be right though, one client has a homebred jenny with a 4" penis at the clitoris and she calves reguarly.
Title: Re: Twin calves
Post by: SallyintNorth on August 12, 2015, 10:42:26 pm
One of the cows in my partners herd is a twin, she's just had her 2nd calf  :)

Female twins are usually both fertile, of course - and for some reason dairy farmers seem very happy to have female twins, lol.

It's luck of the draw whether the female will be fertile if the other twin is a male.   But there's no doubt that some are.
Title: Re: Twin calves
Post by: langfauld easycare on August 13, 2015, 07:39:58 pm
 :wave: the guy who does most of the ai and cattle breeding stuff about here rekond when the heifer could breed she was usualy one of triplets but the cow would have slipped one or reabsorbed etc . said the twins usualy came from the same egg which split but the triplets were separate eggs . not sure but made sense
Title: Re: Twin calves
Post by: SallyintNorth on August 13, 2015, 07:51:14 pm
Twins of different genders cannot possibly be from the same egg.
Title: Re: Twin calves
Post by: harmony on August 13, 2015, 10:19:32 pm
It is very rare in humans but it is possible to have twins of different genders from one egg. Something to do with an extra chromosome[/size] I think.
Title: Re: Twin calves
Post by: Backinwellies on August 14, 2015, 07:22:20 am
Can't see how that could possibly be the case   ........... reference please
Title: Re: Twin calves
Post by: harmony on August 14, 2015, 09:46:55 am
Sorry missed off a word...chromosome


There can be monozygotic boy/girl twins if the sex gene of theembryo has an extra x chromosome (the fertilized egg would be an xxy) then when the egg splits, one can have xx (girl) genes and one can have xy (boy) genes. This is rare, but possible.
Title: Re: Twin calves
Post by: SallyintNorth on August 14, 2015, 10:29:49 am
That Wiki article goes on to say
Quote
This is rare, but possible. Records show there are only 10 known cases of these type twins. The probability of this is so small that multiples having different sexes is universally accepted as a sound basis for in utero clinical determination that the multiples are not monozygotic.

So I'll stand by my statement !   :D

Twins of different genders cannot possibly be from the same egg.


The section in Wiki is about unusual twinnings in humans, there's no information as to whether it is known to ever happen in other mammals.
Title: Re: Twin calves
Post by: waterbuffalofarmer on August 14, 2015, 02:09:49 pm
Why is it when scientists explain stuff they use long words which are a struggle to pronounce? ???
Title: Re: Twin calves
Post by: roddycm on August 14, 2015, 03:44:27 pm
Only about 10% of these male female twins are fertile according to studies. Weird that the same doesn't happen in humans and other mammals, no?
Title: Re: Twin calves
Post by: harmony on August 14, 2015, 04:06:36 pm
I said humans and rare. The female "twin" would have no ovarian development, "Turners Syndrome".

Title: Re: Twin calves
Post by: Blondie on August 15, 2015, 10:45:13 am
Turner syndrome is XO - the person only has a single X chromosome and so although appears female they have certain features which are common among sufferers. They are usually infertile however I know one woman who did go on to have a child despite having Turners.

I don't think you would / could get Turner from being a twin. It's more likely that it's due to the male gamete missing the X.
Title: Re: Twin calves
Post by: landroverroy on August 15, 2015, 09:18:39 pm
But in spite of all these technicalities, no matter whether the twins have come from one egg or two, and regardless of how many X or Y chromosomes are present or missing, are we not still agreed that a heifer calf twinned with a bull calf, is more likely than not to be sterile? :sunshine:
Title: Re: Twin calves
Post by: Marches Farmer on August 15, 2015, 09:24:21 pm
Or, to put it even more simply, would I risk trying to breed from a freemartin?  Answer - no.