CE vs Full gestation.

[elkwc]

In 2021 we started AIing our replacements. The first year we used a sire the AI tech had in his tank. Then in 22 bought semen on some unproven sleep all night heifer bulls. We had mixed results. Some each year were born up to 14 days before due date. They were small but some were lethargic and was slow to get up and suck and also to take off. After doing research and talking to those who calve large numbers and vets I was told those early calves are preemies. So last year selected two proven nine year old sires. The first calves arrived on due date. The last 9 days after. They were small but vigorous. We’re up sucking quicker and have really filled out. Wish more listed the average length of gestation on a sire. At least for us it made a difference.

 

[GoWyo]

We used S Wrangler 830 and everything that stuck has calved. Generally 7-13 days early, but they were vigorous little buggers that were up in 10 minutes trying to nurse with no quit in them. They are filling out nicely at 2-3 weeks age. I was not real excited to see one born 13 days early, but the heifer sneaked him in on me on a 10* night out in the heifer lot and he had nursed but was a little chilled when I found him (had not started the 2 a.m. checks yet) and needed a half hour in the calf oven. All of them were born unassisted.

 

[elkwc]

We used S Wrangler 830 and everything that stuck has calved. Generally 7-13 days early, but they were vigorous little buggers that were up in 10 minutes trying to nurse with no quit in them. They are filling out nicely at 2-3 weeks age. I was not real excited to see one born 13 days early, but the heifer sneaked him in on me on a 10* night out in the heifer lot and he had nursed but was a little chilled when I found him (had not started the 2 a.m. checks yet) and needed a half hour in the calf oven. All of them were born unassisted.

Thanks for the response. We had one born when it was 5-6 degrees. We have no calf oven and they are on their own unless the ground is snow covered. We lost no calves. The tips of a few ears and the tip of one tail. I find it interesting to hear others results.

 

[W.B.]

No calf vigor issues here. Our AI sites both come from real cow outfits. Calves will be 265 to 275 days gestation.

 

[simme]

Seems like shorter gestation bulls would have a positive effect on keeping cows in a defined yearly calving season. Number of days born early also gives the number of extra days post calving to get them cycling and bred back in that yearly window. And a longer gestation bull would leave fewer days to get them bred. Just from a numbers standpoint.