Effective Heifer Pelvis Sort ?

[Stocker Steve]

A recommendation is to not select for the largest pelvis (unless you want really big cows), but to have a minimum size cut off for the smallest acceptable pelvis (to minimize calving problems, or at least ID potential problems). Sounds good in general, but for English heifers:

- what is the minimum pelvis area you would breed to a calving ease bull?

- how would you adjust this minimum pelvis area for purchased heifers that are 5 months bred?

 

[dun]

If their 5 months bred it's a bit late to start thinking about pelvic size. As yealrings we want a pelvic between 155 and 165. The link has a table that gives birthweights associated with different pelvics in heifers
http://www.uaex.edu/Other_Areas/publica ... A-3010.pdf

 

[robert]

Pelvic area is highly correlated to frame score, clearly there will be outliers but for the most part if you select for consistent mature size and use sires that produce daughters who meet your ideal and allow nature to sort out the freaks you'll never need to use calipers again!

 

[mlazyj]

I think your on a crap shoot a 5 months bred . I would keep checking , why with cattle prices up would you take chances with train wrecks . Cull before they ever see a bull . Even with a quality breeding program you'll be looking at 7% cull rate when you pelvic exam.

 

[Aaron]

I have been told (by purebred breeders who pelvic measure a lot) anything under 150 should be culled and anything over 180 is good. There is a high correlation between frame and pelvic area, BUT, there are 'curve benders' in them as well. I missed out on a bull at a sale in 2007 that had pelvic area of 240 and a frame score of 5.5. I asked the vet when he was semen checking this spring about doing pelvic measurements. His advice was to hold off as long as possible. He used to do it (particularly on bulls) and saw big changes in animals at 1 year and again at 2 years. His advice was to hold off as long as possible to get a more accurate measurement, so bulls at 2 years of age, and heifers at 12-18 months. :cowboy:

 

[Stocker Steve]

Thanks for the link. I read the tips, studied up on the division factor, applied all my EPD expertise :dunce: , adjusted up for the hesterois - - to come up with a preg check minimum of exactly 171.8 sq. cm. for my BA bull.

I then compared this to Hereford World where they recommended a preg check minimum of 180 sq. cm.. Sounds about right for an unknown heifer bull.

The 7% cull rate in an interesting number. I have been calving out about 10 heifers per year recently and usually have problems with one. I wouldn't call that a train wreck but I think I can do better.

 

[CKC1586]

I have been told (by purebred breeders who pelvic measure a lot) anything under 150 should be culled and anything over 180 is good. There is a high correlation between frame and pelvic area, BUT, there are 'curve benders' in them as well. I missed out on a bull at a sale in 2007 that had pelvic area of 240 and a frame score of 5.5. I asked the vet when he was semen checking this spring about doing pelvic measurements. His advice was to hold off as long as possible. He used to do it (particularly on bulls) and saw big changes in animals at 1 year and again at 2 years. His advice was to hold off as long as possible to get a more accurate measurement, so bulls at 2 years of age, and heifers at 12-18 months. :cowboy:

Yup, what my vets recommend as well...

 

[mlazyj]

If your 1 in 10 doesn't require a c-section no it's not a wreck . When your calving out 200 , and wearing out a set of chains it puts a new slant on life . 7% cull rate is the average we have hit doing pelvic measurements