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United States Science

Most U.S. Dairy Cows Are Descended From Just 2 Bulls. That's Not Good (npr.org) 85

Posted by msmash from the closer-look dept.
Chad Dechow, a geneticist at Pennsylvania State University who studies dairy cows, is explaining how all of America's cows ended up so similar to each other. From a report: He brings up a website on his computer. "This is the company Select Sires," he says. It's one of just a few companies in the United States that sells semen from bulls for the purpose of artificially inseminating dairy cows. Dechow chooses the lineup of Holstein bulls. This is the breed that dominates the dairy business. They're the black-and-white animals that give a lot of milk. Dairy farmers can go to this online catalog and pick a bull, and the company will ship doses of semen to impregnate their cows. "There's one bull -- we figure he has well over a quarter-million daughters," Dechow says.

The companies rank their bulls based on how much milk their daughters have produced. Dechow picks one from the top of the list, a bull named Frazzled. "His daughters are predicted to produce 2,150 pounds more milk than daughters of the average bull," he says, reading from the website. Farmers like to buy semen from top-ranked bulls, and the companies keep breeding even better bulls, mating their top performers with the most productive cows. "They keep selecting the same families over and over again," Dechow says. A few years ago, Dechow and some of his colleagues at Penn State made a discovery that shocked a lot of people. All the Holstein bulls that farmers were using could trace their lineage back to one of just two male ancestors. "Everything goes back to two bulls born in the 1950s and 1960s," he says. "Their names were Round Oak Rag Apple Elevation and Pawnee Farm Arlinda Chief." This doesn't mean that the bulls in the catalog are genetically identical. They still had lots of different mothers, as well as grandmothers. But it does show that this system of large-scale artificial insemination, with farmers repeatedly picking top-rated bulls, has made cows more genetically similar. Meanwhile, genetic traits that existed in Holstein cows a generation ago have disappeared.
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Most U.S. Dairy Cows Are Descended From Just 2 Bulls. That's Not Good More

Most U.S. Dairy Cows Are Descended From Just 2 Bulls. That's Not Good

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  • Well... derp... (Score:3)

    by the_skywise ( 189793 ) on Friday October 18, 2019 @09:22AM (#59321982)
    That's basic breeding/farming/animal husbandry and I bet if you researched a little further I'm sure you'd find that a lot of our livestock comes from a select few genetic lines.
    Sure, it's more "concentrated" now with less farms and more factory farming and the ability to ship semen worldwide but, like bananas, people grew what works and sells.
    Frankly I'm more concerned with all the milk "processing" that goes on after the fact than the genetic make-up of it. (EG when you buy "whole" fat milk off the store shelf it's usually skim milk with the fat re-added back in)

    • Re: (Score:2)

      by DarkOx ( 621550 )

      Well scale is kinda of important. A whole lot of things are fine until you take them to extremes. Yes selective cultivation/husbandry has been going on since tail end of the stone age. The impacts though might be different as you move from the population of single farms, towns, counties selling trading specimens with each other but still more than likely trading with the folks across the river once in a while who have their own line of cultivars to to an entire continent using mostly the same seed stock!

      I

    • That's basic breeding/farming/animal husbandry

      I found the headline surprising, so I shared it with my wife, who has a degree in biology and grew up on a farm. Her reaction was the same as yours, no surprise at all.

      Frankly I'm more concerned with all the milk "processing" that goes on after the fact than the genetic make-up of it. (EG when you buy "whole" fat milk off the store shelf it's usually skim milk with the fat re-added back in)

      Why does that concern you? I mean, it seems like some wasted motion, but it simplifies the distribution channels.

      • I'm not a "raw milk" guy but I'd prefer my whole milk to be the original milk (homogenized and pasteurized, etc) not extruded skim milk with the fat extracted and then processed/broken down into industrial milk fat which is then re-added to the skim milk to make it "whole". There's a local dairy here that sells milk that hasn't been processed that way. it's pasteurized but not homogenized so you still get the cream and the taste and texture are much better (and I suspect more nutritious)

    • (EG when you buy "whole" fat milk off the store shelf it's usually skim milk with the fat re-added back in)
      That does not sound plausible, why would one remove the fat and add it back again?

    • I bet if you researched a little further I'm sure you'd find that a lot of our livestock comes from a select few genetic lines.

      The classic example is the thoroughbred horse. All thoroughbred horses are descended from one of the "Byerley Turk" (imported into England in the 1680s), the "Darley Arabian" (1704), or the "Godolphin Arabian" (1729). Nobody, but nobody, gives a shit about food genetics, as long as the productivity is high enough and the cost low enough. (That latter includes the lowest possible vet

  • A quarter-million daughters... (Score:2, Insightful)

    by Anonymous Coward

    "There's one bull -- we figure he has well over a quarter-million daughters,"

    Wow! I'm surprised they haven't worn his dick down to a nub yet.

  • And maybe some hot Latin bull action

  • Descended from 2 bulls! (Score:5, Funny)

    by Oswald McWeany ( 2428506 ) on Friday October 18, 2019 @09:27AM (#59321996)

    Descended from 2 bulls!

    It's a miracle, in most mammal species a female is required for reproduction.

  • It could be worse. You could be a bull semen collector.
  • We might learn something about our own future.

  • Monoculture (Score:5, Insightful)

    by bradley13 ( 1118935 ) on Friday October 18, 2019 @09:46AM (#59322048) Homepage

    Monoculture doesn't just mean plants. This is monoculture with animals, and it's a stupid idea for all the same reasons. Short-term productivity gain, but a loss of biodiversity and a huge risk that something could go seriously wrong in the long-term. And if/when it does go wrong? The same farmers and farm-conglomerates that have profited from this short-term thinking will be crying for a government bailout.

    Just yesterday I was reading an article about a local producers of a particular food crop. Which one isn't relevant, because I've heard this story many times before. Anyway, in the first half of the article, the farmers were complaining that they lost money in 2017, because we had a late frost and they had a very small crop. In the second half of the article, the same damned farmers were complaining about the bumper crop they had in 2018 depressing prices.

    There are numerous farmers in my family. There are the farmers who can actually, you know, grow stuff. They plan ahead, they expect variations year-to-year, they manage their land for the long-term, they avoid monoculture and spread their risk across different crops and varieties, etc, etc.. Then there are the farmers who are always after the next government program. I had one uncle whose best farming years were the years he managed to get the government to pay him to leave his land fallow.

    Near as I can tell, eliminating all of the government subsidies and support programs would have a salutatory effect on the whole agricultural industry. /rant

    • Re:Monoculture (Score:4, Interesting)

      by Sique ( 173459 ) on Friday October 18, 2019 @09:55AM (#59322078) Homepage
      There have been examples where this went wrong. In former East Germany, eighty percent of all cows were descendents from a single bull (aptly named Napoleon), and suddenly, there have been numerous cases of deadborn calves where the indestines were malformed. Their guts were disconnected. At first, it was thought that the fetuses were maimed when the veterinary service personal was checking the cows for pregnacy. But further research pointed to a genetic defect.

    • In a land full or dairy farmers, I'm looking forward to the day that "milk" doesn't involve cows. Not soy milk, almond milk etc. Even though they might be a good substitute.

      I'm talking: grass -> factory -> milk. Using bio-reactors, some enzymatic process or whatever. Basically doing what a cows' stomachs are doing without actually using a cow.

      That may sound like heresy around here, but that's my vision. Do away with the "cut rainforest, grow soy beans, feed to cows, get milk"

    • The thing about farmers is that they just like to have something to complain about. Doesn't really matter what is. Get them talking about the weather (they just love to do that) and they'll complain about how it's rained too much or it hasn't rained enough.

      There's a reason they all live out in the country and it has nothing to do with being closer to work. It's because all the people in town are sick of the complaining and kicked them out.

    • Even before this choosing of just a few bulls, thre was a definite move towards sticking only with thoroughbred bulls and avoiding "scrubs" or "mutts". This was exactly at the same time as eugenics was making its rounds in popularity in the1920s. The idea that people can decide to breed animals (or humans) for specific traits; despite bad knowledge of genetics and biology. Witness health issues in purebred dogs.

      https://pvi.virginia.edu/gabri... [virginia.edu]

      • Oh, you can breed animals (or humans) for specific traits; it's a matter of if those traits are useful.

        For humans, particularly, they can be taller, shorter, have longer intestines, darker skin, and so forth.

        There's usually a larger interest in things like intelligence, however; that has complications: human brains are made up of specialized organoids, and they adapt to reduce energy consumption. That includes reducing the effort of such adaptation--i.e. a slow learner becoming a fast learner by being

    • Lets be clear. They are talking only about a single breed of cattle, of which there are dozens. While hostein cows make up the vast majority of dairy cattle in the US, their majority in other countries is far less dramatic. Many markets rely instead on "dual purpose" breeds that are good for both milk and meat.

      Also, haveing shared pedigree does not mean they are necessarily inbred to a huge extent. As the summary highlights, every generation has the dam's genetics as well. Hell, according to a not insigni

  • Thoroughbred horses decended from 3 Stallions (Score:3)

    by ardmhacha ( 192482 ) on Friday October 18, 2019 @10:00AM (#59322100)

    Thoroughbred horses, the type used for horse racing, are descended from just 3 stallions https://en.wikipedia.org/wiki/... [wikipedia.org]

    And more recently a few sires appear in the pedigree of almost all classic winners (sometimes multiple times)

    • However her fathers and mothers are descendents of that stallion ... and other, younger males and females or does anyone think that three stallions are still siring new offsprings?

  • Ancestors, not parents (Score:4, Insightful)

    by bluefoxlucid ( 723572 ) on Friday October 18, 2019 @10:03AM (#59322112) Homepage Journal

    This is like saying your mom is a third-cousin twice-removed from your great-great-great grandmother.

    Bull X has 10 offspring. These offspring each breed with 10 other cattle, producing 10 offspring each. Those 100 out-cross and produce 1,000 offspring, which produce 10,000 offspring, never crossing over the same genetic line.

    At this point, you're several generations down, and all are some kind of descendant of Bull X.

    Humans are all descended from one woman and one man...although they apparently lived 150,000 years apart, and didn't breed together. Essentially, the human population grew, and as it grows of course you have these crossings--people 10 generations in China make babies with people 10 generations in Europe, some of whom have African ancestors not common to Chinese ancestors--and so some genetics gets moved around between parts of the population. Take it far enough and the whole population has some common ancestor, and they probably have another common ancestor above that.

    If you're breeding things, the same sort of thing happens more-quickly. Cats, for example. We bring egyptian mao cats to America and outcross the existing line for four generations, checking for genetic stability. If they remain true to form, we incorporate them into the current base of egyptian mao. New genetic stock. At the same time, these cats must all have a common ancestor somewhere, despite the broad genetic diversity of the breed: all new lines are outcrosses from existing lines.

    • >they apparently lived 150,000 years apart, and didn't breed together.

      You can hardly blame them - that age difference would be pretty insurmountable.

  • "No, let's walk down and fuck them all."

  • From what I've been told, there are about 6 hogs in the US that have basically accomplished the same thing.

  • I don't drink milk regularly but when I do buy it I buy raw milk from a highly reliable source. Fortunately it is legal in California. In many states it is not.

    The cows live on pastures, eat the grasses on the pastures, and they only produce about half the milk per cow that a CAFO cow does. The resulting milk is expensive but much higher quality, and the nutrients are not destroyed by pasteurization (heating) or homogenization (crushing). And it doesn't taste like shit the way the stuff in the cart

    • the nutrients are not destroyed by pasteurization (heating) or homogenization (crushing)

      Which nutrients does pasteurization destroy, exactly? Please be specific. Louis is watching you spout bullshit.
      Pasteurization temperatures don't even reach the boiling point of water.

      Are you instead referring to "ultra pasteurized" milk, which is heated to at least 280 degrees?

      For homogenized milk, WTF crushing are you imagining? Homogenization is merely the mixing of large quantities to ensure evenness across the smaller portions packaged and sold.

      There are straining and separation processes, and proces

      • You sound angry.

        Here are some nutrient components that are deactivated or destroyed by by pasteurization: B-lymphocytes, Macrophages, Neutrophils, Lymphocytes, IgA/IgG Antibodies, B12 Binding Protein, Bifidus Factor Medium-Chain Fatty Acids, Fibronectin, Gamma-Interferon, Lactoferrin, Lactoperoxidase, Lysozyme, Mucin A/Oligosaccharides, Hormones & Growth Factors,

        Sources include Scientific American and The Lancet. From decades back.

        I don't know how all those components act and what their use is.

        • Re: (Score:2)

          by Cederic ( 9623 )

          I just don't see how the assertion that R vs P milk is the same. Maybe you can explain it.

          It's not the same; pasteurised milk is less likely to kill you.

          You need AP to process calcium. If you don't have it you get no calcium benefit from pasteurized milk.

          While pasteurised milk isn't as good a source of calcium as raw milk it is a source of calcium. Don't be silly.

          Raw milk is a choice you can make, but don't pretend that pasteurised milk hasn't been highly beneficial to society as a whole. And don't give raw milk to any pregnant family members.

          • It's not the same; pasteurised milk is less likely to kill you.

            On a per-serving basis, commercial raw milk in the United Stats has caused less disease incidents than pasteurized milk. The reasons should be obvious but there are less-obvious reasons for this.

            As for the pregnancy thing that is also a myth [thehealthy...nomist.com].

  • Increase Genetic Diversity (Score:5, Funny)

    by AnotherBlackHat ( 265897 ) on Friday October 18, 2019 @12:00PM (#59322524) Homepage

    Two?
    Clearly, we need another line of bull.

  • It is worse with most fruit (Score:3)

    by gurps_npc ( 621217 ) on Friday October 18, 2019 @12:33PM (#59322678) Homepage

    Apples, plums, oranges, grapefruits, lemons, mangos, cherries, are mostly grafted.

    That means, they are all clones of fruit that was chosen for it's size and taste. The fruit part of the tree are all genetically identical. (The roots are different kinds of similar trees that have been grafted to a branch from a desired fruit.)

    The most popular fruit that is not grafted is bananas, and they are being attacked by a virus because the bananas we like to eat are all from the same sub-species.

    • Grafting has got nothing to do with it - the issue is cloning, Bananas, grapes, apples, pears, most citrus, etc are clones from a single tree with desirable properties.

      Whether they're cloned onto their own roots or grafted onto the roots of another clone (yup, the rootstock for grafts tend to be clonal mono-cultures too) is not really relevant.

  • So what? Go back far enough and you'll find a common ancestor for all mammals, look up Schrewdinger. My dog and I have a common ancestor at some point in the evolutionary timeline.

  • Now produce cows that generate less methane!

  • . . . didn't that whole Adam and Eve thing work out for the human race, though?

    This stuff is sooooo hard . . . . and get off my lawn, damnnit!
  • Round Oak Rag Apple Elevation and Pawnee Farm Arlinda Chief were standing atop of a hill looking down on a large group of grazing cows. Round Oak Rag Apple Elevation says to Pawnee Farm Arlinda Chief: Hey, let's go down there and **** a couple of those cows. Pawnee Farm Arlinda Chief shakes his head and replies to Round Oak Rag Apple Elevation: No, let the farmers freeze our juice and we can **** 'em all!
  • In that sample heard, maybe. But not ALL of the USâ(TM)s dairy cattle. There are several different breeds of dairy cattle and I guarantee you they didnâ(TM)t come from the same patriarch. That kid should have to rewrite his thesis because itâ(TM)s just stupid and wrong.

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