ai timing

john mayo 10

just wondering what opinions there are out there regarding the length of time from when you would observe a [standing heat] to when you would ai a cow. had too many repeats last year so any thoughts would be very helpful

what happen

between 6 and 24 hours after standing heat commenced. the ai man was telling me to let cows or heifers have cycled once before insemination.

reilig

Rule of thumb - if they are standing in heat in the morning, ai them in the evening and if they are standing in heat in the evening, ai them in the morning. You need to have a flexible ai man/woman though. Mine will come to serve a cow at any time I want.

pakalasa

12 to 14 hours after standing heat is what I've always gone with anyway.


Also did a quick google search and found these;

There was a very good graph showing the likelyhood of conception versus time of AI'ing in the Journal a while back. I think it was on the following article, but it won't open in the link for me. It shows just how important it is to get the timing right. It's not something the AI companies shout about. Not many of them will AI at 12 midnight, will they!

________________________________________________________
The likelihood of conception occurring when insemination is carried out at different times relative to onset of standing heat in beef cows is presented in Figure 3. Fertility is highest following AI at 12 to 18 hours after heat onset, but is not greatly reduced following early insemination. However, late insemination at 24 hours or later after onset of standing heat should be avoided.

From;
http://www.farmersjournal.ie/site/farming-Factors-affecting-conception-rate-in-beef-cows-9176.html

___________________________________________________________
"A cow is fertile only when an egg has been released (or ovulated) from the ovary. This occurs about 10-14 hours after the period called "standing heat" ends. Because sperm need time in the cow’s reproductive tract before they are capable of fertilizing the egg, insemination should be made several hours before ovulation. This means that for the highest fertility, cows or heifers should be inseminated in the latter two-thirds of heat or within a few hours after having gone out of heat. This represents approximately 12-18 hours after the cow first comes in "standing heat."

From
http://www.thecattlesite.com/articles/721/artificial-insemination-for-beef-cattle

mantua

I always use the am/pm rule and vise versa!! like if i spot her in heat at 7am usually ai her at 7pm roughish etc.!!

Bizzum

mantua wrote: »

I always use the am/pm rule and vise versa!! like if i spot her in heat at 7am usually ai her at 7pm roughish etc.!!

Yeah, I do much the same.
If one comes bulling in between times or if it's getting on in the breeding season, We would often AI her twice, ie. Evening and again the following morning. It used be better when the repeats were free but it's €10 now!

AtillaTheHun

did some research on this lately and the sperm will be viable for up to 24hrs. on the other had the egg will only be viable for up to 6hrs. its widely accepted that it is far better to not make the egg 'wait' for the sperm.

so i'd suggest AIing earlier rather than later from standing heat.

but the am/pm rule is still the most useful guide. but maybe if an animal is observed to be in onset of heat in the morning she should be AIed in the evening rather than waiting for 'standing heat'

just my thoughts

atilla

Lofty0990

Is there not some theory out there now that says to serve early in heat for more heifers!

reilig

AtillaTheHun wrote: »

did some research on this lately and the sperm will be viable for up to 24hrs. on the other had the egg will only be viable for up to 6hrs. its widely accepted that it is far better to not make the egg 'wait' for the sperm.

so i'd suggest AIing earlier rather than later from standing heat.

but the am/pm rule is still the most useful guide. but maybe if an animal is observed to be in onset of heat in the morning she should be AIed in the evening rather than waiting for 'standing heat'

just my thoughts

atilla

I suppose the biggest problem with sucklers is that you'd want to checking them 3 or 4 times a day to be accurately identifying the "onset of heat" and the "standing heat".

Studies have shown that a cow may only stand in heat once or twice during each cycle and if you're not there for it, you miss it and you just see what appears to be the onset of heat. So I agree with you that you have to take the chance rather than waiting for the standing heat. I find that Detection patches are a great identifyer - especially as I only get to look at cattle twice a day.

Min

Lofty0990 wrote: »

Is there not some theory out there now that says to serve early in heat for more heifers!

If I have them bulling, I just ring the AI, a lot were AIed early enough, so far - lots of heifers, I think all the advantage straws that were used produced heifers.

pakalasa

Timing is everthing in AI.
I had a cow that was in Standing Heat last night (Sunday).
I have a young teaser bull that was following her as early as Friday evening. I thought she was on heat then. You've got to see the cow standing to be mounted, simple as that.

john mayo 10

I'm really glad i posted this question on this forum as the replys and information that has been posted is very impressive. Thanks for all your help,keep them coming and keep up the gud work.;);););)

Bizzum

I notice the bull shadowing cows coming on heat for 2 or even 3 days beforehand, sometimes giving us plenty of time to take her down for AI in a couple of days. We usually don't though, the bull takes care of them!
It's a high risk strategy running the bull with a cow you're intending to AI, sure as anything, he won't shadow her, but get straight down to business!

jeff greene

AtillaTheHun wrote: »

did some research on this lately and the sperm will be viable for up to 24hrs. on the other had the egg will only be viable for up to 6hrs. its widely accepted that it is far better to not make the egg 'wait' for the sperm.

so i'd suggest AIing earlier rather than later from standing heat.

but the am/pm rule is still the most useful guide. but maybe if an animal is observed to be in onset of heat in the morning she should be AIed in the evening rather than waiting for 'standing heat'

just my thoughts

atilla

My AI man says the same, get the semen into her :rolleyes: early. I AI once a day and get good conception.

funny man

Min wrote: »

I think all the advantage straws that were used produced heifers.

PG would love to hear that. i'm a diy man AI every morning, if a cow is not yet waiting she dosn't get it. just on the female advantage i got a call last week about my complaint on getting 64% bulls from my female advantage, was told that there is an advantage 51%:49%, just wondering who got all my heifers?

Min

funny man wrote: »

PG would love to hear that. i'm a diy man AI every morning, if a cow is not yet waiting she dosn't get it. just on the female advantage i got a call last week about my complaint on getting 64% bulls from my female advantage, was told that there is an advantage 51%:49%, just wondering who got all my heifers?

Oh I made one mistake, all the UPH straws so far produced heifers, the others weren't as good.

what happen

seen the bull roaring down the cattle house hours before cows or heifers are seen bulling in the pens.then i know watch for a cow or heifer bulling and take her out for ai.