Birth weights

[dbirdsong]

Has there been any research done about environmental affects on birth weights? I have had this group of cows for a while and most years my calves range from 60-85 pounds. This year I have had a 96, 97, and 113 pound calf. They have never had calves anywhere close to these weights. The 96 and 97 pound calves are Rampage sons and the 113 pound calf is a Resouce.

 

[dbirdsong]

This is the Resource calf with his EXT dam

 

[dbirdsong]

 

[76 Bar]

Yes. Genetics certainly plays a role but environment is a major and often mitigating factor. Google it.

 

[Bright Raven]

Yes. In my case, Environment = Better nutrition. I have excellent pasture. There is a variety of grasses and clovers. I think that influences my birthweight. My average BW is 88 pounds. This year I had a 97, 112 and 123 as my upper maximums. However, all three were Hooks Broadway sired calves. So in that case, it was genetics.

 

[Redgully]

Lots of factors will effect size and gestation length is one of the biggest. My current herd has a long gestation and i average 90-100 pounds birthweight. My previous crossbreeds used to average 10 days shorter and 20 pounds less. I am still trying to figure out how to change it and have used a couple of different bulls this year selected soley for those traits. I have seven calves due in a couple of months to these bulls.

 

[dbirdsong]

Another strange thing this year is that I out of 17 A.I. calves 13 have been bulls. Just one of those years I guess.

 

[Bright Raven]

Another strange thing this year is that I out of 17 A.I. calves 13 have been bulls. Just one of those years I guess.

I always get more bulls AI than I get heifers. I would guess the ratio is approximately 5 bulls to 3 heifers. From what the semen folks tell me, that is not unusual. The Y spermatozoa endure the freezing process better than the X spermatozoa.

 

[CattleMan1920]

We have had some whoppers this year, much heavier than over the past three years. Multiple AI calves out of SAV sires that were over 100.

 

[LCBulls]

Feed, temperature, time of year, cow size, age of the Dam, sex of calf and Genetics all play a role in size of the calves.

 

[dbirdsong]

I did the math and my calves are averaging 22 pounds heavier at birth than they did last year. That seems to be beyond what you would expect genetically. I did use more performance oriented sires but my cleanup bull last year was a Harvestor x Density son so the calves aren't genetically that much different for birth weight. The only thing that I did differently was leave protein tubs out this fall. Could that make such a increase in birth weights?

 

[Ebenezer]

I did the math and my calves are averaging 22 pounds heavier at birth than they did last year. That seems to be beyond what you would expect genetically. I did use more performance oriented sires but my cleanup bull last year was a Harvestor x Density son so the calves aren't genetically that much different for birth weight. The only thing that I did differently was leave protein tubs out this fall. Could that make such a increase in birth weights?

Yes.