Gestation Length and CE and Vigor

[Randi]

So, as some of you might have gathered from previous posts by me on the topic of Birth Weights, I really, really don't care for the little 60 lb calves...Even out of my heifers...

Last spring we purchased another bull for our heifers, http://abri.une.edu.au/online/cgi-bin/i ... 1&9=535C52
His calving ease so far has been exceptional, but the calves are between a week and 16 days early, so I would hope that they would come out without any trouble! But the problem I am seeing is that these calves, especially the really early ones have a very hard time handling the cold weather. And, we have been having some exceptionally warm weather, so that says a lot. We even had one freeze it's ears, and it was born on a very nice, warm afternoon, but the next 2 days were a bit cooler (still right around freezing) so, not terribly cold. Birthweights here are an average of 64 lbs with a range of 60-68 lbs. All unassisted.

Our other Heifer bull http://abri.une.edu.au/online/cgi-bin/i ... 0&9=535C5E
Has mostly given us calves between 2 and 8 days early and they are much nicer, more vigorous calves. BW here average 81 lbs, with a range of 75-93 lbs. All unassisted.

Last year we calved out a herd of heifers bred to 'Easy Calving' Angus and Red Angus bulls. There were more than one calf that I would say were even premature. The calves out of a lot of these heifers almost looked like fawns. Certainly they were calving ease, the Red Angus calves we never hardly had to touch, thankfully it was a fairly nice calving season weather wise.

So, I guess, what I am seeing is that this Calving Ease thing has gotten to the point where the calves are being born a bit too much on the premature side. Where calf vigour is being sacrificed for Calving Ease. Personally, I would rather have to help a heifer calve, rather than have to keep an eye on them for a few days because they can't handle cool weather.

 

[dun]

Not all calving ease is do to short gestation. More than a week early to me is way too early. The reason those short gestation calves may be having issues with the cold doesn;t have to do with size but maturity at birth.

 

[NolanCountyAG]

I know that we don't have that cold of weather but it seems like the 60lb calves we've had out of heifers this year have had more vigor than the 80lb calves out of heifers.

 

[Randi]

The really short gestation bull is gone, not because of his calves, (that would have been a consideration) but, because of his 'travellin' ways'

But, I have to disagree somewhat on the size vs maturity being the reason the little calves can't tolerate the cold. While, I am certain that maturity DOES make a difference, as far as cold tolerance, I also KNOW that size regardless of maturity makes a huge difference.

Little calves just cannot handle cold weather as well as larger calves. It is simply that they don't have enough body mass to combat cold weather, and they cool down quicker. So, if they don't get up and going immediately, whether it be poor mothering, long birth or whatever, you better be there shortly or they will just lay there and freeze to death. A bigger calf can take the cold for a lot longer, which may simply mean that you have a better chance of finding it before it is too late.

PLUS, on the bottom line side of things, those little 60 lb calves tend to be still 'little' in the fall when sale time comes around.

It is a fine line for heifers IMO, if you want easy calving (which doesn't have to mean tiny calves) plus calf vigor ( too big of calves hurt this too) and growth (little calves at birth tend to be little calves at weaning) In a perfect world, I would like to see calves in that 75-85 lb range for heifers. Small enough that good growthy heifers can have them without help, yet large enough that if mama has milk they will make a decent weight come sale time.

I find that the calves out of the 'bigger' heifer bull have just as much vigor as the little calves do on a nice day, and WAY more than the little calves when the weather is not so nice...

 

[Supa Dexta]

Calf born into a snow storm the other day - 86lbs. Wouldn't want them any smaller. This was taken after searching for it, and brushing off his head when I finally did find him.

And he's up and doing fine.

 

[boondocks]

lucky dude, Supa (both of ya's!). glad he's doing well, wow!

 

[Till-Hill]

Randi I agree with you 100%. These 60# calves are just annoying! They get on one tit and stay on it. Seems like it takes a month to get cows bag all sucked out. Had a 96# Red angus sired calf out of Simmental first calf heifer. That thing was up and going in 5 min and had her completely sucked out by time I came back couple hours later.

I have enough of my own weaning weight data that proves them little calves never keep up come fall.

 

[creekdrive]

The bull we use on our heifers has calves about that size (They aren't early though which IMO would make a big difference when it comes to how vigorous they are). We only weigh the purebred bull calves - but they have averaged 70 lbs over the last two years - that average would be quite a bit lighter if I accounted for heifer calves too. They are probably the most vigorous calves born here. We have to catch them right after they are born to weigh them otherwise we are chasing them all over the pasture... Usually the calf is working on getting up before the heifer even has time to turn around and see what happened. Granted we calve in April when the nights are usually a bit warmer than March, but still rarely do we put any calf inside for the night...if we do it would be because of weather and would be packed in if it was a 50 lb calf or a 100 lb calf. We can get some pretty bad storms in April and I don't remember packing any more little ones in than big ones. Sometimes have to bring one in and dry it off, but once they are dry and have had a good meal they can make it through pretty much anything. If the weather you've been having lately has been as nice as it has been here there is no way you should have to be putting any size calf in any type of shelter for the night.

If we were just breeding strictly commercial animals that 75-85lb for heifers is right where I would shoot for. They still wean off at a decent size and a good heifer should be able to handle that weight no problem at all IMO. Selling heifer bulls though we always try to keep one line of 'sure fire calving ease'. We get a lot of guys that come and don't want anything over 75 lbs - the lighter the better. I sure wouldn't want to sell a guy a bull that had calves that weren't up and going and just as tough as the bigger ones.

Just my opinion, but I think in your case this time the problem was lack of vigor even more so than too small of BW. When they are coming 2 weeks early, no wonder they aren't as a strong. That is definitely taking the short gestation thing too far!

 

[dun]

I think birth weight being equated to vigor is wrong. We used one bull a couple of years ago that had calves that were on their feet so fast they sometimes beat their mommas up. We have cows that no matter who they are bred to the calves are kind of sluggish and others that are up and taking mom for a run across the pasture within a few minutes of being born. The genetics of "vigor" is something that isn;t measured but I sure am convinced that it's there.

 

[Nesikep]

I think if the calf is too big and the birth gets drawn out, you get the dummies. I think 70-80 lbs is good for the first timers, and you can pretty much add 10 lbs birthweight per year after that to maturity.. A 5 year old cow here usually handles 100-130 lbs without any help, though the bombers aren't my goal either, I will say they're hungry and find the 4 quarters much faster, which is good for the cow.
My cows seem to gestate right around 288 days, give or take a few.

I have found a positive correlation between cow families that gestate less and those that miscarry... The families that gestate 290-295 days are the ones that have never had a miscarriage in their history, the ones that usually gestate 280-285 have had several.

 

[Lazy M]

I have found a positive correlation between cow families that gestate less and those that miscarry... The families that gestate 290-295 days are the ones that have never had a miscarriage in their history, the ones that usually gestate 280-285 have had several.

Interesting perspective. So you're saying that in your experience the more fertile cows show greater potential for miscarriage?

 

[Ebenezer]

I think birth weight being equated to vigor is wrong. We used one bull a couple of years ago that had calves that were on their feet so fast they sometimes beat their mommas up. We have cows that no matter who they are bred to the calves are kind of sluggish and others that are up and taking mom for a run across the pasture within a few minutes of being born. The genetics of "vigor" is something that isn;t measured but I sure am convinced that it's there.

Amen. There ought to be EPDs for both calf vigor and mothering ability. They are worth more to a producer than many of the existing EPDs.

...the birth gets drawn out, you get the dummies

I believe this part of the sentence with more conviction. Some of the odd high BW calves, out of range for the cow's history or the bull's average calves, are probably more tied to gestational diabetes or something else that makes them sluggish ever if they are born like a rocket.

While typing: any gestation more than 3 days early is too much.

 

[Nesikep]

Lazy M, I don't equate shorter gestation to higher fertility.. As long as heifers are cycling by when the bull goes out, and they conceive quickly, I consider that as fertile as needed.. I don't need them to be in heat at 6 months.. at all. And as long as they're back in heat 2 months after calving, that's as good as it needs to be to have a calf every year. I have a cow that ALWAYS gestates a long time, Her last bull calf was at 305 days.. yeah, that's a long time but he was vigorous, beautiful and healthy.. nothin' wrong with it except you tear your hair out waiting for her to calf. Bred back with the other cows too. That maternal line has 100% conception to birth to weaning success based on about 80 calves.

 

[Supa Dexta]

How big was that calf? You realize thats 3 weeks over right? As in likely bred the next cycle, or the calf would be 20-30lbs heavier than the avg, as mature cows are putting 1.5lb a day into a calf by that time.

 

[Randi]

I think birth weight being equated to vigor is wrong. We used one bull a couple of years ago that had calves that were on their feet so fast they sometimes beat their mommas up. We have cows that no matter who they are bred to the calves are kind of sluggish and others that are up and taking mom for a run across the pasture within a few minutes of being born. The genetics of "vigor" is something that isn;t measured but I sure am convinced that it's there.

I would agree that some bulls and cows put more vigourous calves on the ground. BUT, when we're talking about vigour in cold weather, calf size definitely plays a factor too.

 

[dun]

I think birth weight being equated to vigor is wrong. We used one bull a couple of years ago that had calves that were on their feet so fast they sometimes beat their mommas up. We have cows that no matter who they are bred to the calves are kind of sluggish and others that are up and taking mom for a run across the pasture within a few minutes of being born. The genetics of "vigor" is something that isn;t measured but I sure am convinced that it's there.

I would agree that some bulls and cows put more vigourous calves on the ground. BUT, when we're talking about vigour in cold weather, calf size definitely plays a factor too.

I agree about the cold needing heavier calves. We've also never had extremely small calves. Our smallest has been around 60 lbs. Even our twins run in the 60-70 lb range. We've had calves that size in single digit temps. It was twins that slipped under the fence when they were born and were frozen/stuck to the ground. The bull was ok when we got him to momma, but the heifer was frozen stiff. Put her in a tub of warm water and thawed her out. and tubed colostrum into her and bottle fed her for a couple of days. Some folks bought her and raised her as a pet. I lost track of her after she turned 3 and was fat as a tick and never bred.

 

[Nesikep]

I see it as 2 weeks over (from 288) from where our average gestation time is. He was a good sized calf, not gigantic.. about 100 lbs. I just looked it up, it was 302, not 305. I really don't think it was from the next cycle... again.. not impossible, but wasn't seen, and this cow has been in the 290's every time since.

For vigor, there's a "right" size I think.. if they're too big it's too hard for them to manage standing as fast as cold weather requires them to, and too small they lose heat too fast.. I think 80-100 lbs is a good weight for a calf.

dun, I'm assuming the people who raised her as a pet knew she was a freemartin?

 

[dun]

dun, I'm assuming the people who raised her as a pet knew she was a freemartin?

They just wanted her for a pet. We were afraid she would lose her feet after being frozen. Had an electronic thermometer and she was too cold to register, they won;t read below 85 f. She ran loose at there place, slept on the porch with their dogs. Damdest thing I ever saw. At least they didn;t let her in the house, couldn;t figure out how to house break her from pooping. The freemartin was why we let the cow raise the bull and got rid of the heifer.

 

[Nesikep]

I kinda figured Sounds like she was quite a pet indeed, and at least she didn't attract the attention of all the bulls in the neighborhood.