fertility

[milkmaid]

Just thinking about it... how big a role do the bull and the cow play in the fertility of the offspring? In other words, is one parent more responsible than the other for how fertile the offspring are (or are not)? I know it seems with udders that the cow plays a much larger part in how her daughters' udders look than the bull does.

Thoughts?

 

[Keren]

They do say that the bigger the testicles of the father, the more fertile the daughter is in terms of reduced post partum infertility, reduced calving intervals etc. they also say a twist in the scrotum of the father tends to create a twist in the udder of the female.

 

[msscamp]

Just thinking about it... how big a role do the bull and the cow play in the fertility of the offspring? In other words, is one parent more responsible than the other for how fertile the offspring are (or are not)? I know it seems with udders that the cow plays a much larger part in how her daughters' udders look than the bull does.

Thoughts?

You're kidding, right? Seems to me that they play equal parts - as the old saying goes, it takes two to tango. If the cow/heifer is a non-breeder there will be no calf. Same thing for the bull if he's shooting blanks, lacks motility, lacks number of viable sperm, or is otherwise lacking on the fertility front. Maybe I'm missing something here, but this question looks like a no-brainer to me.

 

[dun]

Just thinking about it... how big a role do the bull and the cow play in the fertility of the offspring? In other words, is one parent more responsible than the other for how fertile the offspring are (or are not)? I know it seems with udders that the cow plays a much larger part in how her daughters' udders look than the bull does.

Thoughts?

You're kidding, right? Seems to me that they play equal parts - as the old saying goes, it takes two to tango. If the cow/heifer is a non-breeder there will be no calf. Same thing for the bull if he's shooting blanks, lacks motility, lacks number of viable sperm, or is otherwise lacking on the fertility front. Maybe I'm missing something here, but this question looks like a no-brainer to me.

I would agree if fertility was an on or off/yes or no proposition. It's the subfertile animals that cause the problems. The cow that doesn;t start to cycle soon enough after calving or doesn;t settle as fast as she hould or the bull that is just marginal in semen quality

 

[milkmaid]

Msscamp, I'm not talking about freemartins and sterile bulls.

Say we have two hypothetical cows; one that has twins, but has her first cycle at 30 days post calving and settles to it -- and the other cow with a single calf that starts cycling at 60 days and doesn't settle for 6 services. Assuming both hypothetical cows are bred to the same bull (say he's from a herd that averages 3 services/pregnancy) and both throw heifer calves, how fertile will those calves be? Will the calves from the first, very fertile cow, be more likely to take after her, or will we sacrifice some fertility? and the calf of the second, subfertile cow, will she be more fertile than her dam? how much of a role will each parent play in the fertility level of the offspring?

 

[KNERSIE]

Msscamp, I'm not talking about freemartins and sterile bulls.

Say we have two hypothetical cows; one that has twins, but has her first cycle at 30 days post calving and settles to it -- and the other cow with a single calf that starts cycling at 60 days and doesn't settle for 6 services. Assuming both hypothetical cows are bred to the same bull (say he's from a herd that averages 3 services/pregnancy) and both throw heifer calves, how fertile will those calves be? Will the calves from the first, very fertile cow, be more likely to take after her, or will we sacrifice some fertility? and the calf of the second, subfertile cow, will she be more fertile than her dam? how much of a role will each parent play in the fertility level of the offspring?

To answer your question with another question...

If I told you I'll give you $ 1000 if you can throw a baseball and hit the target 30 yards away, where will you look and focus?

At the target off course!

Same principle applies to cattle breeding, if you breed for long enough (don't need to be 50 years ;-) ) you'll soon see female lines showing themselves as more fertile than the rest and typically that line will be the first to finish calving in every season.

Maternal traits and fertility's inheritance is very low (factor of 0.1 if I remember correctly), it means that its a very difficult trait to improve on and luckily also not so easy to lose it if you have it already. To get a more fertile herd you'll make much bigger strides by eliminating those with lower fertility and longer ICP than you'll ever make trying to improve those who haven't.

 

[dun]

To answer your question with another question...

If I told you I'll give you $ 1000 if you can throw a baseball and hit the target 30 yards away, where will you look and focus?

At the target off course!

Same principle applies to cattle breeding, if you breed for long enough (don't need to be 50 years ;-) ) you'll soon see female lines showing themselves as more fertile than the rest and typically that line will be the first to finish calving in every season.

Maternal traits and fertility's inheritance is very low (factor of 0.1 if I remember correctly), it means that its a very difficult trait to improve on and luckily also not so easy to lose it if you have it already. To get a more fertile herd you'll make much bigger strides by eliminating those with lower fertility and longer ICP than you'll ever make trying to improve those who haven't.

I looked at it as a hypothetical question. I know that fertility has a low heritibility but it can be selected for by only keeping replacements (in a beef herd) by only reeetaining the heifers that are born early in the calving season. My old mentor was a dairyman for something like 60 years when I first met him. He only kept heifers from cows that settled to their first AI service, that had been one of his criteria for many years. He had a lot of cows (he milked 600 head) that were in the 10-14 year old range and rarely had to breed a cow even twice to get her to settle, if she didn;t settle by the second service she went down the road. So it can be selected for, but it takes a loooooong time to achive results

 

[novatech]

In some cases fertility is an issue simply because of the wrong cattle are put in the wrong environment.
Proper management with the right cattle in the right environment is just as important as the genetics chosen.
Given the low heritability.
A calf per year from the cow and a bull that can do his job or cull.
I don't care how good or bad a cow is, if she does not produce a calf I have nothing to sell.
Fertility is the number 1 genetic trait that should be addressed in all cattle operations.
Bull fertility is much more complex than measuring the size of their nuts. I would urge anyone to get a breeding soundness exam.
http://www.ext.vt.edu/pubs/beef/400-009/400-009.html

 

[milkmaid]

dun, I don't think the average dairy would be keeping any heifers if they tried applying that criteria to replacements. :lol2: It's pretty amazing.

I thought I culled hard, until I was talking to my uncle who runs several hundred head of beef cows. He said he had the vet out to spay the open heifers this fall so he could run the spayed ones with the steers. Here I'm thinking there's maybe a dozen that get spayed... nope! he had about 40% of the heifers spayed. Has the heifers running on grass pasture and the bulls with them for 32 days. Pretty much only the ones that settle first service get to stay.

Knersie, what's ICP stand for? I imagine something to do with calving intervals?

nova, I liked that article. I had a BSE done on the bull I borrowed this fall... can't afford to have a bull that's shooting blanks. I'm guessing though, that there's way more to this than just selecting bulls that pass a BSE with a good score, because Select Sires is advertising bulls that are very fertile, but the nation's dairy herds keep decreasing in fertility. I've heard dairies bragging about a 25% conception rate. :shock: I don't recall if that's first service or total, but it's still awful.

So it seems that both cow and bull play a large part in the fertility of the offspring, but that fertility is not very heritiable, so that over a single generation there won't be a large change to the offspring's fertility, right? How many generations do y'all suppose it would take to bring a herd from poor fertility to high fertility just by selecting replacements carefully and culling hard?

 

[dun]

dun, I don't think the average dairy would be keeping any heifers if they tried applying that criteria to replacements. :lol2: It's pretty amazing.

I don;t know how long he had been culling like that but he was 18 when his dad died and he took over the dairy. At that time they were milking 20 head. I don;t know if it took 10, 20, 30 years or more to get that kind of fertility. He's been dead for 20 plus years so I can;t ask him.
I know I get real irritated at the dairy whe nthey keep every heifer even if the cow only freshened once and never bred back. I really think you can screw up fertility a whole lot faster then you can fix it.

 

[hillsdown]

Milkmaid we used a young sire bull once ,his name was Ice and for the life of me I can't remember what he was, I am thinking prelude but not sure. Anyways out of the 7 daughters we had from him only 1 conceived first service ,and 4 conceived by the clean up bull and I think 2 were having low fertility. I think one never did conceive even after the gnrh and prostaglandin treatment. This was very odd for our herd as we had exceptional fertility with heifers from first service AI.

Now it was either the bull Ice had low fertility which was heritable or bad luck..I think we culled most of the original group .
Ice never did make it to the proven sire list.

 

[KNERSIE]

I really think you can screw up fertility a whole lot faster then you can fix it.

That generally applies to anything related to breeding.

MM, ICP stands for inter calving period and is measured in days. That is one of the very few measureable indications of a herd's fertility.

 

[milkmaid]

It seems to me with the dairy herds that it's one of those catch-22 things, where they're caught in a downward spiral they can't get out of. If you cull hard enough to get rid of those subfertile cows you won't have a herd left and you won't have any replacements either. :P

Say someone were to try to fix the fertility problems in a dairy herd; how would you go about doing it?

Knersie - so what exactly is the inter calving period? time from one calf to the next or time from calving to cycling again or from calving to rebreeding?

 

[KNERSIE]

Knersie - so what exactly is the inter calving period? time from one calf to the next or time from calving to cycling again or from calving to rebreeding?

From one calf to the next. Obviously the ideal is to be right at 365 days or fewer.

In most dairy herds its just as much production that was pushed beyond the upper limit than it is not enough attention being paid to visible signs of fertility/infertility.

Just look at the scrotums of most dairy bulls.

 

[dun]

It seems to me with the dairy herds that it's one of those catch-22 things, where they're caught in a downward spiral they can't get out of. If you cull hard enough to get rid of those subfertile cows you won't have a herd left and you won't have any replacements either. :P

Say someone were to try to fix the fertility problems in a dairy herd; how would you go about doing it?

Knersie - so what exactly is the inter calving period? time from one calf to the next or time from calving to cycling again or from calving to rebreeding?

I would start out by crossbreeding using non-inbred bulls

 

[milkmaid]

Crossbreeding to -- other breeds? I presume that's why many dairies are starting to shift toward having Jersey x Holstein crosses? I've heard several dairy owners bragging about the fertility of the HoJo crosses.

SC on the two Holstein bulls my boss had checked this summer (one had been injured and needed to be checked, the other I wanted to borrow) was 35 and 37cm. They're probably 2 year olds, maybe 2 1/2 years? According to the website nova posted those are okay numbers, certainly not below the minimum. How do you folks feel about those numbers - good, bad, or ugly?

 

[KNERSIE]

35cm is below my minimum standards, actually its below most minimum standards. I will not look at a mature bull below 38, but preferably between 42 and 44cm. I have yearling bulls of over 40cm.

All that said, its not as simple as SC, the shape, tone, phenotype of the testicles and epididimi as well as the shape, symmetry and length of the scrotum also plays a role.

Milking simmental from Germany and Austria, mostly fleckview is used widely here to be crossed with holstein herds to get a more hardy animal better adapted to grazing.

When I grew up our dairy herd consisted of mostly friesianX jersey cows with a few jerseys and a few friesians to create the F1s. Later on we started using holstein semen (Arlinda chief and Rocco being the popular sires then) but dad sold the dairy herd before he could really say the holstein had a negative effect on fertility.

 

[milkmaid]

So if one has a good Holstein cow, how do you keep breed her back to a Holstein bull and still keep fertility in the next generation if there's such a problem with dairy bulls?

Almost sounds as if a dairy that really wants to improve fertility ought to stop using AI and just raise their own bulls out of the most fertile cows? I note that Select Sires does rank some dairy bulls as "super settlers" and more fertile than others, but it seems as if the numbers they have are only representing what's seen on the microscope slide, not the physical appearance of the bull, which would mean it also says nothing about the fertility of the bull's offspring. Right? The beef bulls SS offers all have SC information, which tells a client about the probable fertility of the bull himself and the fertility of his offspring.

Do I have that right?

 

[KNERSIE]

Yes, you have it right.

The problems the holstein breed have at the moment was caused by the breeders not the breed itself. If a beef breed just focusses on EPDs and push performance higher and higher with complete disregard for phenotype and other functional traits and the environment the cattle have to perform in it won't be long till the beef breed has the exact same problems. The two major beef breeds today has experienced that as well and some herds is still chasing those numbers.

To come back to holsteins... I'd go back and use semen from older bulls that still had acceptable phenotype that are as unrelated as possible to the popular lines of today.

 

[hillsdown]

In regards to dairies is:

#1: poor management.
#2: wrong nutrition program
#3: linebreeding for x amounts of generations..

A lot of dairies also push their cows too hard to maintain a cycle ,compare it to a female Olympic gymnast who works out 15 hours a day and has stopped cycling.
Another thing is having far to long of a lactation because of BST usage (where applicable).

My 2cents Fwiw,,