AI -ing heifers question for the experienced guys

[KNERSIE]

when in the heat cycle does a heifer's cervix start to open and when does it close again. Don't know if I'm putting this correctly, but I am sure the more experienced guys will know what I mean.

Also do you apply the 12 hour rule strictly for heifers as well or do you tend to AI them a little earlier. Here most people AI heifers (mostly dairy, mostly jersey) as soon as they are on standing heat in fear that they might not get the AI gun through if they wait the 12 hours. I, however, AI only hereford heifers and find that if I am too hasty I struggle more to get the gun through the cervix. How do you guys do it? And what others tips do you have when it comes to heifers?

 

[dun]

I just fololow the am pm rule. Passing a pipette while they aren;t in heat is tricky but not really all that hard. I infuse cows for the dairy if they have an infection and they seem to lilnk 3 days after standing heat is the right time. Pipettes in my opinion are hareder to pass then a sheath. Good technique and dextarity and breeding heifers is no different then breeding cows except for size.

dun

 

[MikeC]

Virgin heifers just have a small cervix. Period.

Experience will wash that problem right out of your hair!

Have patience.

 

[farmwife]

Virgin heifers just have a small cervix. Period.

Experience will wash that problem right out of your hair!

Have patience.

Not completely true in my experience.

As for when to ai -- am/pm works well for me.

 

[KMacGinley]

The cervix is never totally closed off unless she is pregnant. There is however more mucous when she is in heat. 12 hour rule works pretty good.

 

[KNERSIE]

thank you for the replies.

I have stuck with the am/pm rule as always, but was curious to know what you all thought about the cervix closing thing. I asume that the local guys I was referring to was all talking about virgin jersey heifers and that their main concern was the size of the cervix in virgin jersey heifers. I have never AI-ed a jersey heifer before, only a few jersey cows for a neighbour.

I am busy AI ing in my 4th breeding season, so I am not a complete novice, but I still learn and gain experience with every heifer I AI.

On a more technical point... from your experience especially with virgin heifers...how do you hold the cervix? in all four fingers and guide the gun in with the little finger, or do you hold the cervix just with the thumb and forefinger? or should I ask if there are any other tricks that come with experience that I haven't learned yet?

Also the heat factor intrigues me. We have two breeding seasons. The summer one being from December 20 - Feb 20(remember we are in the southern hemisphere) This time of the year temperatures average about 35 degrees Celsius,... that would be 95F. The daytime max can go up to 45C(113F). We breed herefords and don't have any problem with poor conception rates in the heat, however the humidity is seldom above 55%.

I guess our cattle have adapted to the heat.(luckily the coldest it ever gets here is about -3C , that would be about 27F. Don't think I can handle much colder.

Could the humidity be the deciding factor, or is it just the heat?

 

[dun]

I hold the whole cervix just like I do with old cows. The heat deal and fertility is strictly a cow thing when doing AI. Anything that causes excessive heat/over heating in a cow about 2 weeks or so after breeding can cause failures. That is, in theory, the time that the embryo is at it's most vulnerable.

dun

 

[andybob]

Humidity is certainly an aggrivatng factor, some breeds which do reasonably well inthe dry Namibian heat are knocked back when similar heat is accompanied by high humidity.