Pelvic measuring cows

[aj]

I was talking to the vet yesterday and she was talking pelvic region. You have different types of pelvic shapes I guess. Some are wide some are tall. And some have a little slope or bump or hitch in the bottom of it. It sounded like measurements are kind of a fail or pass deal. She thought wide was better than tall. A borderline measurement with the little bump or whatever was considered a fail. I was wondering if there was any research on pelvic shape. Do breeds or sires tend to throw certain shapes over others. What about general dimensions? She called the the bump or whatever a Widow's wall. She said the name don't make sense. Is this something that the taking "the survival of the fittest" out of selection has become to surface. Everbody talks about the perfect bull. Wouldn't the perfect bull sire daughters that had perfect pelvic regions. I'd kinda lost interest in pelvic measurements but this is kinda interesting stuff. What is the heritability factor in this stuff? has there been ANY research on this? Would there be a dna marker that marks the perfect pelvic shape? I guess the over maternal calving ease epd would maybe cover the thing but is there room to take it to the next level.

 

[OKshorthorn]

What all goes into measuring it? Something that needs to be done by a vet? I'm interested in this too, I would think that there has to be a genetic link from a bull to his offspring with it. I want a bunch of cows with a tall AND wide minus the widows bump, what bull is going to give me that?

 

[kfacres]

a pelvic-o-meter... is all that's required.. it's a reverse, blue thing that you put in and measure vertical and horizontal...  can be done by anyone.

 

[OH Breeder]

http://extension.missouri.edu/p/G2017


University of Nebraska researchers developed ratios that you may use to estimate deliverable calf size. You can divide total pelvic area prior to breeding by a ratio that is based on age and weight to estimate the amount of birth weight a heifer could accommodate as a 2-year-old without substantial difficulty.

Example: A 600-pound yearling heifer  with a pelvic area of 140 square centimeters should be able to deliver, as a 2-year-old, a 67-pound calf without difficulty (140/2.1 = 67).



The vertical measurement is the vertical diameter between the symphysis pubis on the floor of the pelvis and the sacral vertebrae. The horizontal measurement is obtained by determining the horizontal diameter at its widest point between the left and right ileal shafts (Figure 2). These measurements are read in centimeters and multiplied together to obtain the total pelvic area in square centimeters.

Figure 2
Obtain vertical and horizontal measurements to determine pelvic area

 

[OKshorthorn]

Thanks for the info guys!

 

[willow]

I just thought I would add...... Firstly I believe BS when he says "anyone can do it"  it isn't rocket science, however we had two different cattle vets give us the measurements on the same group of heifers and they were significantly different.  So much so that I would have pitched that group of heifers based off of the one vets reading.  I also believe pelvic measurements can be a handy tool.
We originally got pelvic measurements on every heifer we ever decided to keep mostly because that is what was "par for the course" around our area when it came to keeping/breeding clubby females.  At the time it was said that "these heavy boned females have smaller pelvic openings".  Whether that is true or not I have no idea.  A few years into that genius plan we stopped getting the pelvic measurements done.  The reason we stopped getting them done is we just got comfortable with the way things were going and at that point it seemed like an unnecessary step for us.  I also knew because of the inherent birthweight that our crossed up clubby bred cows carried and the crossed up clubby bred bulls we were breeding to it was never going to happen that we would ever have that 60 some pound "deliverable" calf that the "rice pelvimeter" said we could have with minimal difficulty.  We breed heifers very conservatively and watch our cattle I personally think that is the only fool proof method. JMO   

 

[DL]

a pelvic-o-meter... is all that's required.. it's a reverse, blue thing that you put in and measure vertical and horizontal...  can be done by anyone.

IMHO the primary use of pelvic measurements in heifers is to find those with the peanut sized pelvis and cull her. The reproducibility of pelvic measurements between people is poor (meaning if you (generic) and I both measure the same animal it is likely we will get two different answers); further although the very small pelvic area may predict for dystocia there is a huge overlap between those not so tiny and not having issues with those not so tiny and having issues - so the predictive value of the pelvic measurement is not very good.

There are basically 2 kinds of instruments - the Rice Pelvimeter which is sort of like an elongated x and a hydraulic type. You are really after pelvic area (height times width) and the area needs to be adjusted for age - there is an adjustment factor for each day over or under 1 year; you need to measure the maximum height and the maximum width - it isn't difficult but it does take a bit of practice to be good/accurate -

 

[kfacres]

I just thought I would add...... Firstly I believe BS when he says "anyone can do it"  it isn't rocket science, however we had two different cattle vets give us the measurements on the same group of heifers and they were significantly different.

which is why I put very little effort towards believing one vet all the time- instead of poling the pool. 

Kinda like the time we took 5 heifers to be preg checked, and they ranged from 3 months to almost 6.  Ended up they calved within 5 days of each other. 

 

[JSchroeder]

We put a glove on and just check them ourselves when they're yearlings.  Once you've done ten or so you won't need a tool or measurement to tell you when some of those oddly shaped small ones come through that they're going to have a problem.

 

[aj]

I wonder if the deal on the pelvic floor that Kristy was talking about is the ventral symphysis crest? I guess if real accurate pelvic measurements with the tool aren't possible it might be hard to id sires or develop dna tests cause each cow would have to be killed to get a good accurate consistent measurement. Pretty impractical. I have heard that feedlot heifers have real tiny calves alot of times if a mistake is made. I wonder why that is? Something about a real hot ration?

 

[nate53]

On some females their pelvic starts expanding well before calving (weeks) and others don't look they have expanded at all the day they calve?  THoughts?
AJ the few we've calved out of the feedlot weren't small, but they weren't giants either, average (80's) size is more like it on the few we have done.  These females would have gotten bred by a mature bull at 6months of age   
or less.

 

[kfacres]

On some females their pelvic starts expanding well before calving (weeks) and others don't look they have expanded at all the day they calve?  THoughts?
AJ the few we've calved out of the feedlot weren't small, but they weren't giants either, average (80's) size is more like it on the few we have done.  These females would have gotten bred by a mature bull at 6months of age   
or less.

genetic and hormonal...

I have manually expanded first time ewe lambs before-- not easy.. and in almost every case the ewe's lambs die- or she prolapses. 

feedlot deals_ 18 month old heifer calved 102 lb bull.. hard bull.. calf didn't walk for two days.