Horn breeding

[cmf1]

Just got back from AI school again at McNeese State in Lake Charles, La.
One of the Phd's talked about horn breeding for increased preg rates.

Paraphrase:
"If you palp the cervix left handed it opens the right horn a bit more. 90-95% of pregnancies occur on the right. Studies show that after 20 minutes semen has migrated to the left horn as well.
The Phd is an embryologist as well, so is used to messing around in the horn.

The techs, when asked, weren't sold on going past the uterus, but the uterus is the spot, not the cervix.

I know there are various techniques, various rates of success, and many other things have to line up as well as semen placement for pregnancy.
I'm intrigued about horn breeding and curious as to how others feel about it.
Thanks.

 

[TexasBred]

cmf my wife has always "horn bred" with exceptional results. Unfortunately that's about all I can tell you about it.

 

[regolith]

Halfway through the cervix gets most of them - and is much safer. I didn't know the semen could migrate effectively from one horn to the other if it was all deposited in one.

I'm using cervix-breeding now as nearly all the cows have been inseminated at least once already, so there is the possibility of inseminating a pregnant cow who is showing signs of heat. I don't know if all techs do that but it was certainly strongly recommended in training not to let the inseminator into the uterus on a return to heat.
The dye-trace photos they showed us in training proved that the best technicians often had very poor positioning. Some of those dye clouds were halfway up the right horn.

cmf, if you could get more info on the 90 - 95% of pregnancies occur on the right horn it would be interesting. Is that all pregnancies, or just AI ones? Is the cow ovulating predominantly on the right horn, or does it mean she's more likely to get pregnant on the cycles when she ovulates on the right rather than the left?
For sure if she happens to be ovulating on the right and you get the semen in the right horn you've probably got your best chance of getting her pregnant - what I don't fancy is her chances if she happens to be ovulating on the left.

 

[Lucky_P]

Looks like that 90-95% number is not right...

http://www.ncbi.nlm.nih.gov/pubmed/19962748

http://www.sciencedirect.com/science/ar ... 0254913843

 

[cmf1]

Thank you Lucky P.
So while he was apparently well off on the horn percentage, (or I take lousy notes) with a positive % still to the right horn and him stating that migration of semen to the left horn occurs, do you think that horn breeding can increase conception rates?

Regolith,
That's a very good question regarding rebreeds that was not considered during his lecture. A definate strike against horn breeding on a rebreed in my mind.

I have learned a lot about AI over the last few years and I know that I don't have to know all I want to know in order to breed cows artificially.
I am pretty much fascinated with the concept and the practice and variations involved. I don't have nearly enough experience to promote or detract on techniques, just an appetite for discussion.

 

[Lucky_P]

cmf1
I think you'd have to know which ovary was ovulating the egg to know which horn best to inseminate into.
Just because the pregnancy implants in one horn, doesn't absolutely mean that it's in the same horn as the ovary that released the egg, but even if that were to be the case, you'd have to palpate the ovaries and determine which one was about to ovulate a follicle.

I don't know how many inseminators ever palpate ovaries, or do it often enough to feel confident predicting ovulation; maybe some do. Even as a practicing veterinarian, I rarely had occasion to palpate ovaries, since most of my palpation work was just pregnancy diagnosis - never really had much opportunity to do much in the way of 'repro' work beyond that. I can tell the difference between a follicle and a CL, but as rapidly as sperm are distributed throughout the uterus - both horns - I don't know that I'd bother taking the time to find and palpate ovaries if I was inseminating.
But, my wife is the inseminator here, and does uterine body deposition; maybe TB's wife can provide more insight into how she decides which horn to inseminate.

 

[Bigfoot]

I didn't know a person could feel of an ovary, and know it was the one producing. I try to find the cervix, and leave everything else alone. It seemed like something I didn't need to be squeezing on.

 

[TexasBred]

I didn't know a person could feel of an ovary, and know it was the one producing. I try to find the cervix, and leave everything else alone. It seemed like something I didn't need to be squeezing on.

Bigfoot some of the folks use to say "hold the ovary with one hand and your nuts with the other. Never squeeze the ovary any harder than you would squeeze your nuts". :nod: :lol2:

 

[KNERSIE]

I think we are overthinking this, I was taught to deposit half the semen in the uterine body then pull back and leave the other half in the cervix (just in case you went in too far without knowing it) This has always worked well for me, although I stopped leaving half in the cervix as I grew more confident, but even now still you get a cow with a humungous cervix and can't be sure how far you actually went through the cervix. In such cases I will revert back to puling back and leaving half in the cervix.

 

[cow pollinater]

Every study I've ever seen on horn breeding concluded in "don't do it".
Most beginning breeders do it on accident The proper placement in the uterine body is about the size of a dime on most cows and for about an inch past that you can feel the tip of the gun just fine even if you're in the horn.
Palpating ovaries is really pretty simple but I don't do it... What's the point? If she's hot, breed her.

 

[Lucky_P]

I'm with you, cp.
Put it in the uterine body - it'll get where it needs to go from there. Or it won't. IF I were inseminating, I don't think I'd be palpating ovaries; OK, maybe if I was using some obscenely expensive semen, but that ain't happening here!
Only time I palpated ovaries was if there was some thought about whether a cow was cystic or some concerns about no ovarian activity.
The equine repro folks will palpate 'em , and the good ones will be able to say, "She'll be ovulating in X days, breed her then". I tried to stay out of, and as far away from, horses(and their crazy owners) as possible!

 

[regolith]

I'm with you, cp.
Put it in the uterine body - it'll get where it needs to go from there. Or it won't. IF I were inseminating, I don't think I'd be palpating ovaries; OK, maybe if I was using some obscenely expensive semen, but that ain't happening here!
Only time I palpated ovaries was if there was some thought about whether a cow was cystic or some concerns about no ovarian activity.
The equine repro folks will palpate 'em , and the good ones will be able to say, "She'll be ovulating in X days, breed her then". I tried to stay out of, and as far away from, horses(and their crazy owners) as possible!

When I first came to NZ (fifteen years ago) it was standard practice for dairies to present every cow that hadn't cycled by the start of mating for a vet to examine. I've worked on a 360 cow herd and seen the vet so exhausted he could hardly hold the spraypaint to mark the cow for a CIDR. You won't persuade a vet to do that now. They recommend CIDR-synch based on things that can be observed externally and only examine exceptional cases.
Too many times the farmer would write down a remark like "CL on the right she'll cycle" and then blame the vet when she didn't, between that and the exhaustion and the fact that nearly every diagnosis was treated by the same method (cidr) the vet industry as a whole decided it wasn't in their interest to do those exams.

Concerning cycling - I'm very interested to observe how some of my cows can have a weak heat flanked three weeks either side by strong heats. I'm trying to observe heats that show next to no signs, by writing them down and later checking the return dates. And being 100% AI this year, by week 4 I was mating on extremely minimal signs; there's no bull to sniff them out if I can't. So I've got a new category of PD checks - cows I mated on next to no signs with no return observed.
I think something is different this year and some cows are having weaker heats. When I've checked return dates on cows that were seen standing beside bullers but not playing, they're very often around 21 days later.
I had one cow have a strong heat premating that I watched from about day 17 to day 26 and saw nothing and the tailpaint wasn't scuffed. On day 42 she cycled and I was wishing I'd just gone ahead and mated her on day 21 - because I bet she had a fertile ovulation then. But you can only predict that with hindsight. Would have been 100% on observing returns on pre-mating heats but she pushed me back to my normal average of 99%.

 

[midtncattle]

I think having a bull calf or steer in the field helps identify those heats.

 

[TexasBred]

I think having a bull calf or steer in the field helps identify those heats.

About a 350-400 lb . bull calf with a bit of jersey will definitely catch them all. Usually about 3 days early. ;-)

 

[cmf1]

All good stuff.
Thanks.
Theoretical concept vs real practice maybe.
He sure made it sound good.
I'm sure I've bred the horn before, but not on purpose. From what training I have the uterus is my objective. I'll leave the horn to those more knowledgeable than me. (imagine how long that list is :lol2: )
Another point made was slow removal of the gun so as not to create a vacuum and "undeposit" the semen from where you placed it.
I'm too slow to begin with so I wasn't really concerned. But the next cow I bred I had to wonder if that's a real problem for some. And I withdrew pretty darn slow with that in mind.
I'm sure most of this stuff is just to make you think about what you're doing and reiteration of basics, which is good, but I still had to wonder.
Do you pay attention to the speed at which you withdraw, or believe the vacuum concept?

 

[KNERSIE]

The vacuum story is a first for me, what I've been taught is to stimulate the clitorus whilst the gun is still in the cervix before puling it out, the contractions is supposed to help the distribution of the semen in the uterine body to both horns. (if you're doing it right ;-) )

 

[cmf1]

Do you find that a discharge is an indicator of doing it right?


I don't mean to step on Inyati's toes here. ;-)

 

[dun]

Do you find that a discharge is an indicator of doing it right?


I don't mean to step on Inyati's toes here. ;-)

When I wa doing cutom AI for people that only had one cow I went almost completely by the discharge. Clear and watery too, early, milky too late, clear but some thickness was just right

 

[TexasBred]

Do you find that a discharge is an indicator of doing it right?


I don't mean to step on Inyati's toes here. ;-)

THAT and a little "moaning". :lol2: :lol2: :hide:

 

[cow pollinater]

Vacuum? That's a creative new one.
Over the years I've seen guys do alot of weird stuff thinking it's going to make them a better breeder. To date the best breeders I know just have a ton of cow sense and dump semen in the right spot and leave the rest up to the cow. You can cut alot of corners and have fantastic results as long as you put semen in the right spot on the right cows.