Bull selection based on scrotal

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I heard something I don’t understand one bit today: pretty well the top criteria is scrotal must be 40cm or above. On a yearling. My jaw about hit the floor. For a few reasons: 1. Scrotal measurements are not a science at all. Different people will get different measurements. 2. That’s a very large number on a yearling. I’d almost be concerned he will get a little bit too big. I think there is research that over a number (38 maybe?) there’s not much difference in semen production 3. I’m sure not gonna pass over a bull I like quite well if he has a respectable measurement.

I do understand the research on scrotal and puberty but for that criteria to be the be all and all mostly because of my point #1 just floored me.

Discuss.
 
Strange but the guy that hauls my calves to the sale barn sent me this today . Here is a list of black angus bulls he hauled for a breeder to the NE Alabama bull sale . Don't know the ages but check out the scrotal measurements. I would think all are 15-18 months old . Only 2 are 40 . 🤠IMG_6947.jpeg
 
I've always thought it was fertility of the bull himself, not his daughters... although I suppose that it could still be "genetic fertility" that he would pass on then too... If he has "high fertility", his offspring then would also be more likely to be. But the biggest reason for the concern, as I understood it, was so that he would be a good breeder.
 
I'd like to know how it translates/transfers over to their daughters. Huge nuts equals what on his daughter?
Fertile females
Big scrotal has a direct relationship with high libido in bulls. I was always taught that a bull with big nuts could settle a cow every 7 minutes.

Big scrotal bulls will have daughters who mature faster and come into heat younger.

We really push maternal traits in our cows. We're getting ready for our bull sale next month BSEing bulls this week or next. Bulls are 12-15 months old and there should be several 40cm+ bulls.

32cm is the pass/fail magic number for yearling angus.
 
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Fertile females
Big scrotal has a direct relationship with high libido in bulls. I was always taught that a bull with big nuts could settle a cow every 7 minutes.

Big scrotal bulls will have daughters who mature faster and come into heat younger.

We really push maternal traits in our cows. We're getting ready for our bull sale next month BSEing bulls this week or next. Bulls are 12-15 months old and there should be several 40cm+ bulls.
32cm is the pass/fail magic number for yearling angus.
That is what "they" say but libido has nothing to do with passing a BSE or the semen test. Libido needs to be checked or observed or else you can get rooked on a one bull per pasture setup. Have had it 2X here over the years. There have been research effort to establish libido testing in a standardized manner.

The quicker daughters (fast women😆) is a matter of only a FEW DAYS if you go back to the research. It really was not significant. I do not have it now but looked it up. Large SC became a fad and still lingers, for some reason beyond the research.

Yearling SC minimum is 30 cm for the industry.

Historically, bulls like EXT and Bando were "female makers". To go to the sire search and put in max SC of zero and see which "great bulls" pop up makes me wonder if the SC size is a legitimate culling point.
 
Adding to my post: a friend went to a sale to buy a young bull several year ago. It was an internet auction, he was close by and just drove over. The bull he had wanted from an early look at the herd did not sell. He bought it after the sale at base price. The seller wanted to move the rest and made some offer. One that the seller liked or recommended had not sold so James bought it, too and there was another one that was about at beef price so he took a 3rd one. All BSE and semen tested. Put all 3 in with 17 heifers just to see what happened. I think that he said that one bull sired 15 calves, one 2 and one none. No apparent injuries, no real signals of dominance, fairly equal bulls. So how important was the SC size and passing the BSE?
 
That is what "they" say but libido has nothing to do with passing a BSE or the semen test. Libido needs to be checked or observed or else you can get rooked on a one bull per pasture setup. Have had it 2X here over the years. There have been research effort to establish libido testing in a standardized manner.

The quicker daughters (fast women😆) is a matter of only a FEW DAYS if you go back to the research. It really was not significant. I do not have it now but looked it up. Large SC became a fad and still lingers, for some reason beyond the research.

Yearling SC minimum is 30 cm for the industry.

Historically, bulls like EXT and Bando were "female makers". To go to the sire search and put in max SC of zero and see which "great bulls" pop up makes me wonder if the SC size is a legitimate culling point.
100%. I couldn't remember the bull I was thinking of... EXT. I've heard about his smaller jewels but he was a prolific breeder.

I calve in the fall now due to a dud bull. Had a nice set and had passed his exam. He was not at all interested in the girls. None.

This franchise bull doesn't have big nuts but he wastes zero time. I think a "willingness to breed" test would be far more useful than measuring the size of the testes. Shape and how they set, indeed, but not the size.

Thanks.
 
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Adding to my post: a friend went to a sale to buy a young bull several year ago. It was an internet auction, he was close by and just drove over. The bull he had wanted from an early look at the herd did not sell. He bought it after the sale at base price. The seller wanted to move the rest and made some offer. One that the seller liked or recommended had not sold so James bought it, too and there was another one that was about at beef price so he took a 3rd one. All BSE and semen tested. Put all 3 in with 17 heifers just to see what happened. I think that he said that one bull sired 15 calves, one 2 and one none. No apparent injuries, no real signals of dominance, fairly equal bulls. So how important was the SC size and passing the BSE?
Apparently there WAS some signals of dominance between the bulls though... boys will be boys... unless they're "confused".:rolleyes:
 
I've heard tell of a bull that had small nuts but his daughters were super fertile as was he himself.

100%. I couldn't remember the bull I was thinking of... EXT. I've heard about his smaller jewels but he was a prolific breeder.

I calve in the fall now due to a dud bull. Had a nice set and had passed his exam. He was not at all interested in the girls. None.

This franchise bull doesn't have big nuts but he wastes zero time. I think a "willingness to breed" test would be far more useful than measuring the size of the testes. Shape and how they set, indeed, but not the size.

Thanks.
Apparently size DOESN'T matter...
 
That is what "they" say but libido has nothing to do with passing a BSE or the semen test. Libido needs to be checked or observed or else you can get rooked on a one bull per pasture setup. Have had it 2X here over the years. There have been research effort to establish libido testing in a standardized manner.

The quicker daughters (fast women😆) is a matter of only a FEW DAYS if you go back to the research. It really was not significant. I do not have it now but looked it up. Large SC became a fad and still lingers, for some reason beyond the research.

Yearling SC minimum is 30 cm for the industry.

Historically, bulls like EXT and Bando were "female makers". To go to the sire search and put in max SC of zero and see which "great bulls" pop up makes me wonder if the SC size is a legitimate culling point.
I think it’s probably even more important on the lower end.
Just my personal experiences; at work we breed heavily for material. They have for twenty five years. In the past when they didn’t have enough people calves didn’t always get weaned/ separated as soon as they should. This is strictly A.I. and no cleanup bulls until the calves are weaned and the cows go to pasture. 4-5 month old bull calves were settling 5 month old heifers.

Now the flip side; I work with a purebred angus herd that uses bulls. They have two pastures so they use two different bloodlines exclusively for several years then switch. They have been using a fairly popular angus bull for awhile now and what we are finding is that at 14-15 months the bulls struggle to pass their BSE because their nuts are so small. The hfrs are so late maturing that they struggle to pass pelvic measuring. The mature cows on this farm probably average close to 1,800lbs we’re not talking about belt buckle cattle.

Now on to libido; that is probably the biggest reason I push people to turn over their herd bulls. Old bulls tend to get lazy and not chase cows like a younger bull. I’ve had that happen with a couple Hereford bulls.

At work the bull lot is right next to the hfr lot. We A.I. on natural heat. Those hfrs will go tease the young bulls and the bulls are lined up screaming like a bunch of teenage boys trying to see inside the girls locker room.
 
I'm no expert and don't claim to be, but this seems like one of those things that someone came up with and it was fun to talk about... and people started to take it seriously so it stuck. Eventually the conversation evolved to sound like there are legitimate reasons.
We all know that cows get bred by a cryptorchid bull that was banded and one testicle was missed. It only takes a single sperm... and there are anywhere from 4 to 10 billion in a single ejaculation. In fact we harvest and split a bulls ejaculation for artificial insemination, anywhere from 50 to 500 times each.
Someone started this conversation back in the day, and I wonder if he's getting a good laugh in the afterlife...
 
Well, then might make sense to buy those 27cm scrotal bulls or those cryptorchids. They can be bought pretty cheap relative to the 36 to 40 cm bulls.
I can definitely tell you that you'll never catch me taking a measuring tape to a bull. I can tell by looking if he's got nuts. But if people want to use a measurement and it makes them feel they are getting a superior bull, good for them.
 

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