Low Birth Weight Question

[JWBrahman]

What is the ideal low birth weight for a calf? 50lbs? 60lbs? 70lbs? The weight at which a calf is considered lbw?

My purpose in raising this question is the other day I saw the smallest calf to ever drop out a birth canal. It would be generous to say it weighed 40 pounds. The first thought in my mind is we have taken the low birth weight thing too far. That little calf is at a higher risk of being food for the vultures and coyotes.

Is 30-50 lbs too low and would you cull that from your herd?

 

[dun]

Unless it's an anomaly I don;t want anything under 65 pounds, 70-75 is more in keeping with my desires. I don;t really like anything over 85 pounds but will shade that to 87 pounds if it's late. Nothing scientific, just my persoanl likes and dislikes

 

[Oldtimer]

Unless it's an anomaly I don;t want anything under 65 pounds, 70-75 is more in keeping with my desires. I don;t really like anything over 85 pounds but will shade that to 87 pounds if it's late. Nothing scientific, just my persoanl likes and dislikes

I agree... 70-75 is about perfect... Extreme highs and lows both most often present their problems- altho I prefer a low BW calf with lots of vigor that are up and running around like jackrabbits soon as they are born (like those you will get from bulls like N Bar Prime Time D806) over the high BW calves (that you often get crossbreeding with some continentals) that end up plugging up the hole or being big dummies after they hit the ground and often lay there and die in our unpredictable environment...

 

[branguscowgirl]

In my particular Brangus girls it would be unusual, (and a concern) to see anything born under 75 to 80 lbs.. However a different breed and frame of cow a 65 lb. calf may be the norm.
With that said,
I think a lot depends on the size of your cows. Even breeding to a low birth weight bull, if the cows nutrition is good and she has a lot of "room" inside, you are going to get a good size healthy calf.
If the calf is small and vigorous, no big deal. If it is small and weak, better ask yourself some questions.

 

[3waycross]

Unless it's an anomaly I don;t want anything under 65 pounds, 70-75 is more in keeping with my desires. I don;t really like anything over 85 pounds but will shade that to 87 pounds if it's late. Nothing scientific, just my persoanl likes and dislikes

I agree... 70-75 is about perfect... Extreme highs and lows both most often present their problems- altho I prefer a low BW calf with lots of vigor that are up and running around like jackrabbits soon as they are born (like those you will get from bulls like N Bar Prime Time D806) over the high BW calves (that you often get crossbreeding with some continentals) that end up plugging up the hole or being big dummies after they hit the ground and often lay there and die in our unpredictable environment...

What a load of horseshyt.............

It also helps if you done have a bunch of hatchetassed heifers that couldn't pass a cocker spaniel puppy without a pull. It also helps if that "hole" as you call it isn't a pelvic slit that looks like () instead of this( ).

I have seen my Gelbvieh heifers drop a 90lb balancer bull calf(unassisted) that was up and sucking in less than 15 min.

 

[branguscowgirl]

More common than not, my Brangus calve 90-100lbs. Unassisted.
The only cow I have ever helped in 14 years, (and probably did not need to) was one first calf heifer. She was pretty restless so I just hurried things up for her.

 

[dun]

It also helps if you done have a bunch of hatchetassed heifers that couldn't pass a cocker spaniel puppy without a pull. It also helps if that "hole" as you call it isn't a pelvic slit that looks like () instead of this( ).

And there in lies the reason we pelvic all our yrarlings and have minimum size required or they go to the feedlot. Although the pelvic measurment isn;t fool proof. Friends of our had a bull they were really proud of, the pelviced all of his daughters and they were adequate as yearling for supposedly an 85 lb calf IF they continued to grow as they should. His daughters kept a bunch of us up nights pulling calves. Turns out that he sired one of those anomolies that drive you nuts. As 2 year old his daugheters had hardly added anything to the pelvic opening. Tjose were the kind that could hardly pass a weaniedog puppy, let alone a decent sized calf. The vets and the AI tech all had the same comment. "Dmandest thing they had ever seen."

 

[dun]

More common than not, my Brangus calve 90-100lbs. Unassisted.
The only cow I have ever helped in 14 years, (and probably did not need to) was one first calf heifer. She was pretty restless so I just hurried things up for her.

We've had some heifers drop 90 lb plus calves unassisted, still not desireable as far as I'm concerned. We pulled a dead calf last year from a heifer. Calf had one leg folded across it's chest put she has still managed to get it half way out. Temp in the single digits and a week early. Calf was frozen to death and frozen to the heifer. Poured warm water over it and pulled it with just a fair tug with the calf jack. Calf weighed 89 lbs. Cow was fine and bred back first service after being a nurse cow for another calf who's momma had very little milk. The latter cow is gone to the great freezer in the sky and the other is due early february

 

[Rafter S]

I want a small calf from my first-time heifers. I've had some I could pick up with one hand under their chest like you would a dog, and I'm fine with that. I don't give any thought to birth weight for the bulls I use on my mature cows.

 

[3waycross]

In fairness to the OP the question here was not about heifers. So my answer is if your cowherd is dropping 50 to 60 lb calves they better be some growin sunsguns or that low BW is gonna bite you in the butt at the sale barn later on.

 

[Katpau]

I always wonder how many of these little 60 to 70 pound calves I hear about had their weights actually measured with an accurate scale. My first calf was born last week. I usually calve in February but I bought a couple bred heifers last summer. The place I purchased them reported mostly small calves in the mid 60 to 80 pound range. I was curious if these calves would be smaller than my average. When I first saw this little heifer I guessed her maybe 65 pounds. She could easily run beneath her heifer mom. I was surprised when we lifted her and got a weight. She actually weighed 78 pounds which adjusts to 85 pounds for an adult cow. I thought maybe my scale was off, so I reweighed her with both a digital scale and the hanging scale two days later, and she was at 82 pounds, so it was right. She was stout and her weight was pretty deceptive.
I suspect many use eyeball estimates and others may use tape measure estimates. I tried the tapes along with scales for a number of years and found the tape often underestimated the weight of the calf by as much as 10 or more pounds. I calve about 40 to 50 cows per year and weigh every single calf with a hanging scale that I verify against a digital scale. My cows are small to average in size with most at a 4 to 5 frame score. My average birth weight last year was 90 pounds. That varies a bit from year to year depending on weather and bulls, but is usually in the mid 80's to low 90's. I very rarely need to assist. Occasionally I might observe a backward calf or a leg back, and I will help if I see that, but assistance is very rare. The only one I lost last year was a 60 pound calf out of a first calf heifer. It was born in a storm that was switching back and forth from rain to snow. I found that one in a puddle probably dead of hypothermia. My cows are on pasture and not near the house, so I can't watch them every minute and I would not want to. If they can't have a decent size calf even as a heifer, then they don't have a place here.

 

[sim.-ang.king]

In fairness to the OP the question here was not about heifers. So my answer is if your cowherd is dropping 50 to 60 lb calves they better be some growin sunsguns or that low BW is gonna bite you in the butt at the sale barn later on.

But I thought smaller calves meant you could have more of them?





:lol2:

 

[3waycross]

In fairness to the OP the question here was not about heifers. So my answer is if your cowherd is dropping 50 to 60 lb calves they better be some growin sunsguns or that low BW is gonna bite you in the butt at the sale barn later on.

But I thought smaller calves meant you could have more of them?





:lol2:

litters

 

[robert]

Usually a cow or heifer will try and deliver approx. 5 to 7% of her bodyweight on deliverable calf. To me it makes sense to select replacements from the one's that replicate themselves under our management program, which basically means "have a calf on your own, every year, own it, raise it and give me something marketable that pays your feed Bill and then some". Cow that do this usually live to a ripe old age here.

 

[robert]

Pelvic measurement was the big deal 25 years ago, but was found to be highly correlated to frame size therefore selection for larger pelvis = selection for larger frame size. Measurement can certainly identify those few individuals with problematic small size pelvic area however.

One trait we do monitor and select for is short gestation which Will positively improve calving ease due to the rate the calf is growing in the womb during the final month of gestation.

 

[Fire Sweep Ranch]

If my cattle can not have an 80 pound calf unassisted he does not belong in my herd, period. Like 3 way said, you are too far behind at weaning when you start low like that. We weigh everything on a True test scale, dam and calves at calving.
Now, we have had a very small heifer (50 pounds at birth) half simm half angus, and ended up with a yearling weight of just under 900 pounds. She is bred to calve at 12 months and I have no concerns about her laying down and spitting out a calf. But she is an unusual case of a small birthweight calf growing to adequate size.

 

[ALACOWMAN]

More common than not, my Brangus calve 90-100lbs. Unassisted.
The only cow I have ever helped in 14 years, (and probably did not need to) was one first calf heifer. She was pretty restless so I just hurried things up for her.

That's pretty stout birth weights for Brangus..

 

[Andyva]

Ideally, I would like to see a 900 pound heifer have a 60 pounder and a 1400 pound cow have a 95 pounder. Narrow hipped cows and the size and shape of the calf's head have more to do with birthing problems than size alone. Sometimes long gangly calves with long legs will get tangled, too. I think there is a direct relationship between the 60 pound BW and the 375 pound WW. If you select for one trait, other traits suffer.

 

[dun]

Pelvic measurement was the big deal 25 years ago, but was found to be highly correlated to frame size therefore selection for larger pelvis = selection for larger frame size. Measurement can certainly identify those few individuals with problematic small size pelvic area however.

One trait we do monitor and select for is short gestation which Will positively improve calving ease due to the rate the calf is growing in the womb during the final month of gestation.

Frequently it is correlated to FS. But a 160 as a yearling doesn;t matter if it's a FS 4 or 7, the hole is still the same size. And with normal growth will be large enough to calf unaided as a 2 year old unless it's a particularly large calf. Ours run FS 5 - 5.5 and our minimum at yearling is 160.

 

[AllForage]

If my cattle can not have an 80 pound calf unassisted he does not belong in my herd, period. Like 3 way said, you are too far behind at weaning when you start low like that. We weigh everything on a True test scale, dam and calves at calving.
Now, we have had a very small heifer (50 pounds at birth) half simm half angus, and ended up with a yearling weight of just under 900 pounds. She is bred to calve at 12 months and I have no concerns about her laying down and spitting out a calf. But she is an unusual case of a small birthweight calf growing to adequate size.

Hybrid vigor and a feed bucket can do amazing things