Inbreeding

[HerefordSire]

Please read text:

"Over 20 million parentage records of Hereford cattle were used to evaluate inbreeding levels and rates of change from 1900 to 2001. Inbreeding levels increased on an annual basis until 1966, where a maximum level of 11.5% was calculated. During the 1970s and 1980s inbreeding levels decreased and by the 1990's inbreeding was increasing and reached a level of 9.8% by 2001. The reported decrease in inbreeding is unusual since the Hereford population is relatively closed. Additional analysis suggested that there were two potential causes for the decreased inbreeding levels. These were a shift to types or lines of Herefords that were not as popular before 1966 and/or the importation of genetic resources from Canada. While one or both of these causes led to a reduction in inbreeding that reduction was transient, as inbreeding increased again in the 1990s. From 1990 to 2001 the effective population size of the breed was calculated and found to be 85 animals. The study provides a benchmark of current genetic diversity in Herefords and can be used in monitoring future changes and if need be developing conservation strategies."

http://www.ars.usda.gov/research/public ... 115=173558


(1) Any comments about the following sentence?

The reported decrease in inbreeding is unusual since the Hereford population is relatively closed.

(2) Does ayone see a pattern in the dates of the trend reversal in 1966 and the trend reversal in 1990?

 

[KNERSIE]

(2) Does ayone see a pattern in the dates of the trend reversal in 1966 and the trend reversal in 1990?

Yes, that one is relatively simple to explain. Prior to 1966 the drive was for smaller, earlier maturing, pony type cattle. Then after the whole dwarfism debacle the eyes opened and the breeders looked for outside genetics that wasn't reduced to dinky toy size. The drive for larger frames continued this trend till the late 80's untill the eyes opened again and they realized they went too far in the other direction.

Some of the older pure lines (that was traditionally linebred, like the Prospectors, who were in the frame 4.5 region) was introduced back. The most famous bull resulting out of such a mating is Feltons 517. The drive for moderation and the heavy use of bulls like 517 resulted in an increase in inbreeding since 1990.

 

[Third Row]

I assume they use Wright's Coefficient to determine inbreeding?

If so, how many generations back do they go?

 

[Aero]

I assume they use Wright's Coefficient to determine inbreeding?

If so, how many generations back do they go?

does it really matter? 20 million parentage records should be enough.

 

[Badlands]

With 20 million records, they went nearly all the way back.

Inbreeding coefficients were computed for the entire pedigree and mean inbreeding was calculated by year from 1900 to 2001.

Badlands

 

[HerefordSire]

Yes, that one is relatively simple to explain. Prior to 1966 the drive was for smaller, earlier maturing, pony type cattle. Then after the whole dwarfism debacle the eyes opened and the breeders looked for outside genetics that wasn't reduced to dinky toy size. The drive for larger frames continued this trend till the late 80's untill the eyes opened again and they realized they went too far in the other direction.

Are you sure it is not too simple? In other words, could there be 1966 blood in the herd from a source not expected like Simms? Any other ideas that do not agree with the government of your post?

Some of the older pure lines (that was traditionally linebred, like the Prospectors, who were in the frame 4.5 region) was introduced back. The most famous bull resulting out of such a mating is Feltons 517. The drive for moderation and the heavy use of bulls like 517 resulted in an increase in inbreeding since 1990.

 

[HerefordSire]

I assume they use Wright's Coefficient to determine inbreeding?

If so, how many generations back do they go?

I know of no other measurement to measure inbreeding than the Wright Coefficient, do you? If so, I would like to study those also.

Good question. I believe the text mentions 12 generations but it is not real clear of the actual formulas used. A family tree, or pedigree, is alot like computer bytes because everything is based upon 2 as in two sets of genes combine to make one living individual AND it take two parents to make one descendent.

If...0x00000000 is one hexidecimal byte in a computer or one measurment in a gene in an animal in the off state and 0x00000001 is one byte in a computer or one atom in a gene in an animal in the on state, then...I can combine them and represent them in a computer by..0x00000001. Like wise, a branch in a pedigree can be represented by 2 << 1, or 2 * 1, and then 2 << 2, etc. in each layer representing each generation...I believe some researchers like to go back to 1,024 which is one kilobyte in a computer, or 1000 bytes, or 2 << 8.

 

[KNERSIE]

Yes, that one is relatively simple to explain. Prior to 1966 the drive was for smaller, earlier maturing, pony type cattle. Then after the whole dwarfism debacle the eyes opened and the breeders looked for outside genetics that wasn't reduced to dinky toy size. The drive for larger frames continued this trend till the late 80's untill the eyes opened again and they realized they went too far in the other direction.

Are you sure it is not too simple? In other words, could there be 1966 blood in the herd from a source not expected like Simms? Any other ideas that do not agree with the government of your post?

Some of the older pure lines (that was traditionally linebred, like the Prospectors, who were in the frame 4.5 region) was introduced back. The most famous bull resulting out of such a mating is Feltons 517. The drive for moderation and the heavy use of bulls like 517 resulted in an increase in inbreeding since 1990.

Herefordsire, the % inbreeding is calculated from parentage records or pedigrees not bloodtests.

I am sure that at some stages "outside genetics" was used. The jump from frame 1 to frame 10 was just to sudden to be believeable in my opinion. But if that information wasn't disclosed it will not affect the % inbreeding theoretically.

Traditionally herefords were in the frame 4-5 range, then reduced to miniature size, how they managed to even reach a frame 10 is beyond me. I'm not sure single trait selection alone can achieve that.

I know this is a touchy subject, would love to hear more opinions from other hereford breeders.

 

[Brandonm2]

[I am sure that at some stages "outside genetics" was used. The jump from frame 1 to frame 10 was just to sudden to be believeable in my opinion. But if that information wasn't disclosed it will not affect the % inbreeding theoretically.

Traditionally herefords were in the frame 4-5 range, then reduced to miniature size, how they managed to even reach a frame 10 is beyond me. I'm not sure single trait selection alone can achieve that.

I know this is a touchy subject, would love to hear more opinions from other hereford breeders.

This was one you USED to hear a lot of bad rumours about......
http://www.msu.edu/~ritchieh/historical/ace_broker.jpg
Frame TEN!! and I think his daughters didn't milk AT ALL; so that kind of shoots the Simmental theory out of the water. He and MSU Top Knight Ryder (an 8.7) were giants.

 

[HerefordSire]

Herefordsire, the % inbreeding is calculated from parentage records or pedigrees not bloodtests.

In English, it is not uncommon to represent blood line, or heritage, of lineage, as "blood". I agree with you.

I am sure that at some stages "outside genetics" was used. The jump from frame 1 to frame 10 was just to sudden to be believeable in my opinion. But if that information wasn't disclosed it will not affect the % inbreeding theoretically.

The reason I posted the abstract is because it exploded in front of my eyes. In other words, it is very hard to change the percentage inbreeding magnitude of that many individuals in such a short time period. If I am not mistaken, the peak is almost equivalent to 12.5% inbreeding which is like the progeny of two half-siblings and siblings would be 25%. The 11.? percent inbreeding number is very high...and then all of the sudden, she goes into a tail spin and bottoms in 1990.

Traditionally herefords were in the frame 4-5 range, then reduced to miniature size, how they managed to even reach a frame 10 is beyond me. I'm not sure single trait selection alone can achieve that.

The small to large frame number appears like is an equilibrium force or a springing reaction to counter opposing forces (..equal and opposite force..) as the result of specific genetics injected in the year 1965, or there abouts.

I know this is a touchy subject, would love to hear more opinions from other hereford breeders

If something unethical happened, I think there are several people with fathers and grandfathers that may have information but they are tight lipped as their livlihood may depend on it even though they could probably be thrust on Fox, CNN, ABC, NBC, CBS, and write a book or two, etc. They would become millionaires very quickly.

 

[KNERSIE]

In English, it is not uncommon to represent blood line, or heritage, of lineage, as "blood".

I understand English pretty well, thank you!

I am also well aware of terms used when parentage are discussed.

My point is, that if there was something else, but herefords in the 1966 "blood" as you prefer to call it, it wasn't recorded or disclosed and would have no influence in the calculations that came to the 11.5%. If any other "blood" was introduced after 1966, it would still have no influence on the calculations that rendered the 9.8 % in 1990 as they use pedigree records to do the calculations. If something isn't officially recorded it can't have any influence on the official % of inbreeding.

 

[HerefordSire]

I understand English pretty well, thank you!

I should have never used the word "blood" in the context. My mistake. By the way, that wasn't supposed to be an english lesson. Just me communicating to you my meaning.

I am also well aware of terms used when parentage are discussed.

?. I hope so as you are my teacher. :cboy:

My point is, that if there was something else, but herefords in the 1966 "blood" as you prefer to call it, it wasn't recorded or disclosed and would have no influence in the calculations that came to the 11.5%. If any other "blood" was introduced after 1966, it would still have no influence on the calculations that rendered the 9.8 % in 1990 as they use pedigree records to do the calculations. If something isn't officially recorded it can't have any influence on the official % of inbreeding.

Good point! Now you have me thinking. If there was a dilution, the animal(s) would not be registered. If DNA tests were done on all Herefords alive, could it be proved if there was a non-Hereford in the gene pool? If one non-registered bovine mated with a registered Hereford, is each sire proved to be the parent, and likewise, is each dam proved to be a the parent? The way I understand it, the DNA analysis is only performed with using AI and ET as proof and not during natural matings. So theoretically, the dam or bull reporting information could be swapped with another dam or bull, correct?

Also, the document does not disclose the percentage at the bottom of the trend, only the two peaks. I wonder why this information is not disclosed since they had it available?

 

[Aero]

how they managed to even reach a frame 10 is beyond me. I'm not sure single trait selection alone can achieve that.

in a mature cow, a frame 10 is only 7 inches taller than a frame 6. granted, it would be a monster of a cow but not that hard if you have no other criteria. look at chihuahuas and st bernards, they are practically identical genetically.

 

[KNERSIE]

how they managed to even reach a frame 10 is beyond me. I'm not sure single trait selection alone can achieve that.

in a mature cow, a frame 10 is only 7 inches taller than a frame 6. granted, it would be a monster of a cow but not that hard if you have no other criteria. look at chihuahuas and st bernards, they are practically identical genetically.

Aero, you must remember the norm then was frame 1 and 2, not frame 6 cattle. There was no taller cattle back then in the hereford breed, the tallest would have been frame 4 and 5 and they were those that got "left behind" So there wasn't a huge gene pool to select the taller genetics from to go from ponies to racehorses and they did it in about 13 years!

That sound too good to be true to me. In that same era headshapes and eyesets also changed from the traditional.

 

[Aero]

That sound too good to be true to me. In that same era headshapes and eyesets also changed from the traditional.

i have no doubt that "other" blood was brought into the Angus breed that did the same thing. it's much easier to cover up with a black animal. i guess some semmintal (or other red animal) wouldnt be that hard to hide with hereford.

i dont know enough about specific breeds to know exactly what the difference in eyesets would look like, but i understand what you mean.

 

[BAGTIC]

The furor over 'how pure' a breed is is much ado about nothing.

Remember that most 'pure breeds' are relatively new, 150 years or so. When these breeds were first established there were not any standards. Every breeder bred cattle the way they, personally, thought they should look. Whether angus, hereford or other 'breed' they were a pretty motley and varied lot.

After the registeries were created owners bred to registry standards. It was an early form of marketing/branding. They could say, 'See, ours are purer/holier than their's'. The fringe benefit was that by providing a more hogeneous gene base they were able to provide a more uniform, not necessarily 'better', product so buyers could more accurately anticipate the outcome of breeding.

There are some who believe the most important part of maintaining the breed is fixating on some past (original?) characterisics, imagined or real. Good examples of this are Dexter breeders who want to maintain chondrodysplasic dwarfism and breeders who don't want to go polled because it is not traditional. Of course some humans believe that the historical accident of one of their forebearers arrived on the Mayflower makes them special too.

What concerns me is that some of the commercial cattlebuyers have fallen in to the trap that appearances are more important than performance. When I read posts that says white cattle with points are discounted over solid whites on appearance alone, that creams sell better than pure black, or minor breeds of otherwise good confirmation and growth are being downgraded , not because of provable inferiority, but because of a buyers personal prejudices it convinces me that cattlebreeding is fast becoming the equivalent of auto body design, interior decorating, and female fashion.

 

[HerefordSire]

The decrease in inbreeding during the 1970s was of
particular interest in the study. The additional analysis
performed demonstrated that the decrease could have
been due to two separate breeder actions: 1) a shift in
the lines used (as reflected in the decrease in genetic
relationship between the most heavily used bulls), and
2) outcrossing to imported breeding stock that, from the
American Hereford Association's records, had unknown
parentage. Although both of these factors may have
caused the decrease in average inbreeding, this effect
was transient, as inbreeding started increasing again
in the 1990s. The analysis that evaluated animals with
at least 12 generation pedigrees also was instructive,
as it provided an upper limit of inbreeding levels.


I located the actual document and can be accessed here:

http://jas.fass.org/cgi/reprint/83/5/992.pdf

 

[Herefords.US]

Aero, you must remember the norm then was frame 1 and 2, not frame 6 cattle. There was no taller cattle back then in the hereford breed, the tallest would have been frame 4 and 5 and they were those that got "left behind" So there wasn't a huge gene pool to select the taller genetics from to go from ponies to racehorses and they did it in about 13 years!

That sound too good to be true to me. In that same era headshapes and eyesets also changed from the traditional.

Knersie, I disagree with this statement just a bit. While seeing a lot of US Hereford cattle in the early 60's that were frame 3 & 4, I don't remember seeing very many that were as small as 1 & 2's.

In 1962, we bought this bull from Palo Pinto Anxiety 4th Hereford Ranch off his dam:

http://www.herfnet.com/online/cgi-b...56&5=2B3C2B3C3A&6=5B5C5A5A5A59212122&9=5B5F5F

He matured into a bull that measured 58 inches tall at the hip (FS 6). He was typical of many of their bulls produced at that time.

They had a very large herd that took 4 days to disperse when they sold in the mid-sixties.

Also, cattle breeders like Eaton Becker, Cooper, Holden, and several others were producing larger framed Hereford cattle. They were the leaders in performance testing their herds, most starting in the mid-fifties.

We purchased this bull from Pied Piper Farms in 1965 that had an adjusted WW of 725 lbs. I still have the PRI (Perfomance Registry International) certificate on him somewhere in my father's estate items:

http://www.herfnet.com/online/cgi-bin/i4.dll?1=232B21&2=2420&3=56&5=2B3C2B3C3A&6=5B5C59272320262224

While not quite as tall as the D462 bull, he was easily a frame 5+. Certainly having the genetics to grow that large, he was definitely given optimum opportunity to do it early on. He had been picked for Pied Piper's show herd and not only was he getting momma's milk, but all the feed he wanted as well as milk supplement from a "black and white" surrogate mother.

Eaton Becker produced this bull:

http://www.herfnet.com/online/cgi-b...56&5=2B3C2B3C3A&6=5B5C265B27232F2423&9=5B5F59

who was over 60 inches tall.(FS 7)

We had a daughter of a Becker bred bull (and a granddaughter and great-granddaughter of the other bulls) that produced a bull calf in 1982 (sired, natural service, by a bull that was 3/4 Cooper Line 1 Breeding) that was truly an outlier.(We nicknamed him Jumbo) His WW % was 142%(raised entirely on his dam) and he measured a FS 8 as a yearling:

http://www.herfnet.com/online/cgi-b...56&5=2B3C2B3C3A&6=5B5C24585A59262122&9=5B5D5E

Granted it took years, but it was only 4 generations from a FS<4 cow(Dulcinea L) to a FS 8 bull. And 4 generations can be done in much less time.

There were a lot of Hereford cattle around in the early 60s that were FS 5 to 6 framed cattle.

George

 

[KNERSIE]

George thanks for the reply, its a pity there isn't more actual information on them in their performance pedigree page.

I am sure there was frame 5-6 cattle and I am sure the selection of taller framed cattle could have been done and eventually end up in about frame 8s. I just question the total shift in almost the entire hereford population. You don't have any photos of those bulls or other cattle out of those era in your collection that belonged to your family?

 

[Herefords.US]

George thanks for the reply, its a pity there isn't more actual information on them in their performance pedigree page.

I am sure there was frame 5-6 cattle and I am sure the selection of taller framed cattle could have been done and eventually end up in about frame 8s. I just question the total shift in almost the entire hereford population. You don't have any photos of those bulls or other cattle out of those era in your collection that belonged to your family?

I have some pictures if I can locate them...all amateur photos. The Becker bred bull was featured in ads at the time.

Yes, TPR was just getting started in the sixties, so little performance information isn't there until the later generations. We only recorded WW as we never kept a lot of the calves long enough to get YW ratios as a group. We never kept BW records at all. We measured height and kept other records like pigment, red color, amount of white, etc, but those don't show up on the performance pedigree.

Also, Daddy was a religious record keeper that was one of the few that actually did what was requested and he returned certificates of registry to the AHA when he sold the cattle at the sale, after their productive life was over, so I assume that might be why we aren't still shown as the owners of record on some of those cattle.

The FS 8 bull was sold before he was a yearling to a woman who had commercial cattle. I had priced him at a price 3 times higher than the other bulls we had to her and never dreamed that she would actually buy him. She only got one crop of calves from him before he was struck by lightning. Sometimes it doesn't pay to be the tallest animal in the herd! :lol: (I'm 6'5")

George