Aged Bull and cow Fertility

ebclark7992 · Aug 17, 2015

Does anybody know of any studies or research done that shows a bulls fertility will fall off after a certain age? Ive been told everything from age 3 and up. Also of any research done showing when a cows fertility will fall off and she will no longer cycle/breed like she should. If you could post links to what you have that would be much appreciated. Thank yall!

Lucky_P · Aug 17, 2015

Studies of semen quality by theriogenologists indicates that fertility declines pretty precipitously after age 7. Add to that issues with increased mature weight, arthritis and injury... you're rolling the dice on an older bull. Sure, some get the job done well into their teens... but not the majority of them.

Sold our most recently purchased bull a week or so back - at age 10. He's really not had much to do for the past 7 years but clean up behind AI. Moving slow, and I was having some concerns about his fertility (yeah, I know you're REALLY rolling the dice if you don't do a BSE prior to each breeding season, but I'd not done it). So...it was time for the old boy to go. Really nice disposition that he passed on to his calves - but I'm now seeing that he was an udder destroyer.

Cows... I dunno. Have had some of 'em calve like clockwork up to 17, 18 yrs, but we usually cull 'em out on age around 10... if they don't cull themselves earlier.

bmoore87 · Aug 17, 2015

Cows for us seems like 12-13 they start coming up open more frequently. Usually we start noticing they aren't raising as good of calf and holding body condition before/in conjunction with fertility issues starting.

Bulls usually flip at 6 or 7. do have one little guys that we use on heifers that is 12 and tests good every year. Don't know if Id keep one around that long if we didn't test.

WalnutCrest · Aug 17, 2015

I have a guy trying to convince me the rule of thumb is a bull should be able to cover one cow per month of age starting at with their ability to get 85% + on a motility test, until they're around 4yrs of age (i.e., breeding 48 cows/heifers), then, they drop about a half-a-cow per month until they're about 7yrs (i.e., breeding 30 cows/heifers). After 7yrs of age, some stay steady for a while, and some drop off a cliff. Heck, I once read about a bull in my breed who was still covering 15 cows / yr into his 17th year.

So, I guess I'll just say ... who knows ... it's all very dependent on the bull themselves. What sort of care did they get, what sort of genetics did they get, what sort of environmental stresses did they have, were they ever injured, etc.

Nesikep · Aug 18, 2015

About 7 is about as old a bull as I'll keep.. I am not in a position where I can do BSE's with out huge expense, but recently I've started keeping a second, younger bull on hand.

Cows, well, they usually cull themselves gradually... I had one old cow that had 16 calves, was late a couple years but always caught right back up, her senior years she actually was always among the first to calf.. she would have probably bred back again but I kept her away from the bull, her arthritis was getting too bad. Her oldest daughter is 10 next year and she's been great, her mother had 13 calves.

Stocker Steve · Aug 18, 2015

ebclark7992":1h02u37h said:
will fall off after a certain age?

Bull disposition often goes after 4 years. Bull studs usually carry bulls well into their teens. Really depends on how you house and use them.

Cows can breed almost forever. Most folks give up at about 10 years. Really depends on how you feed them.

Ojp6 · Aug 18, 2015

We bought a set of 16 year old cows one time for another guy that had been really well taken care of them. There was 7 of them and the guy that we sold them too said they all raised a calf for 4 more years and then he killed them out.