BW

[herefordkid]

Ive been looking in some of the sire catalogs and have noticed a trend in the past 10 years or so that Birth Weights have been climbing exponentially now personally i don't care for pulling calves on first year heifers but maybe Im missing something.

 

[jkwilson]

Ive been looking in some of the sire catalogs and have noticed a trend in the past 10 years or so that Birth Weights have been climbing exponentially now personally i don't care for pulling calves on first year heifers but maybe Im missing something.

Exponentially? I think that's a wee bit of an exaggeration. Have any examples?

 

[novaman]

Ive been looking in some of the sire catalogs and have noticed a trend in the past 10 years or so that Birth Weights have been climbing exponentially now personally i don't care for pulling calves on first year heifers but maybe Im missing something.

Exponentially? I think that's a wee bit of an exaggeration. Have any examples?

I was thinking the same thing when I started reading this thread. I cannot understand why there are so many people are so concerned about BW. There are so many things that affect BW that you can't judge ease of calving by the weight of the calf. This is why there is a calving ease EPD. This is why you look at the shape of the shoulders and head of bulls prior to buying them. Personally I love pulling calves on first calf heifers :roll:

 

[Frankie]

I was thinking the same thing when I started reading this thread. I cannot understand why there are so many people are so concerned about BW. There are so many things that affect BW that you can't judge ease of calving by the weight of the calf. This is why there is a calving ease EPD. This is why you look at the shape of the shoulders and head of bulls prior to buying them. Personally I love pulling calves on first calf heifers :roll:

Yes, a lot of things affect birth weight, but there is a lot of research showing the heavier calves are more likely to be problems than the lighter calves. Bull buyers are interested in actual birth weights, too.

Plus, we used the Angus BW EPD for a lot of years successfully as a calving ease indicator. So I wouldn't discount birth weight concerns.

 

[novaman]

I was thinking the same thing when I started reading this thread. I cannot understand why there are so many people are so concerned about BW. There are so many things that affect BW that you can't judge ease of calving by the weight of the calf. This is why there is a calving ease EPD. This is why you look at the shape of the shoulders and head of bulls prior to buying them. Personally I love pulling calves on first calf heifers :roll:

Yes, a lot of things affect birth weight, but there is a lot of research showing the heavier calves are more likely to be problems than the lighter calves. Bull buyers are interested in actual birth weights, too.

Plus, we used the Angus BW EPD for a lot of years successfully as a calving ease indicator. So I wouldn't discount birth weight concerns.

I agree that heavier calves tend to have more problems. I agree that the BW EPD would have a high correlation to calving ease. My arguement is that too much weight is being put on the actual BW. It is alarming to me at how few people use EPD's or at least that's the vibe I'm getting by reading in this forum. You would think the whole livestock industry is going backwards by the comments I have been reading. As the years have been going by I am seeing an overall improvement in everything from calving ease to fertility. Genetically we are making advancements with every generation entering the herd.

 

[MO_cows]

The question was, why have birth weights gone up so much?

My answer is, because there was selection for growth, growth, and more growth and the mature frame size of most breeds of cattle went up. A pound here, a pound there, the birth weights came along with the frame.

One of the PhD's from CSU, where a lot of the cattle evaluations that generate EPD's gets done, spoke at the Tarentaise meeting one year. The question posed to him from a member was - what's more important when selecting for calving ease, the BW or the CED EPD? His answer, the calving ease EPD, because it had more factors weighted into it.

 

[Frankie]

The reason BW EPDs are going up might just be that more, accurate data is being reported.