(some names have been removed to protect the innocent)
I am writing to see if you can help me with background knowledge for science class. The 6th graders have previously studied evolution and with it artificial selection and are currently studying the nitrogen cycle. Both of these are directly relevant to cattle ranching. And as your family are ranchers (this is correct, no?), I wanted to discuss with your son how these scientific concepts directly affect his own family. Also, I am curious about the answers.
How involved his your family in the breeding of the cattle on its ranches? What qualities are selected for (size, ability to put on wait, etc)? Are the genetics of the cattle examined? Have your family seen changes or improvement in breeds over time?
A big part of the nitrogen cycle has to do with feces and its decomposition. Animals poop, it gets broken down by bacteria and fungi, nitrogen compounds are released into the soil, etc. It's a whole circle of life thing. However, as I'm sure you know excess fecal contamination in aquifers and runoff is a bad thing. Does your family ranch deal with cattle waste? What should one be aware of when thinking about this issue?
I realize that you are very busy. Any help you could give would be much appreciated.
Have a good weekend.
Mr. Science Teacher
Hey man, good to hear from you.
Yes, the family business is very active in selective breeding and we maintain multiple cow herds, for different markets, bred for different traits.
On a macro scale, all of the individuals in each herd have to fit a basic standard based on economics and environment. The animals must be structurally sound so that they can walk long distances to water, they must be able to efficiently grow on the native grasses that are present, be able to survive the relatively cold winters and hot summers that we have in the Sandhills of Nebraska, and must be able to reproduce on schedule once a year and raise the calf to weaning without assistance.
We have a herd of registered Hereford cattle that is for seed stock production. This is a small herd of females, about 100 or so, that are selectively bred using AI to whatever bull we think will make a good match. The offspring are then sold to other ranches that want to improve their genetics. A smaller sub-group of these females are sort of the "elite" group and they get super-ovulated a couple times a year, the eggs are then flushed out and implanted into recipient cows (who are good mothers that give a lot of milk, but don't have any of the other traits we are looking for) so that the donor cows can have a litter of anywhere from 2 -20 offspring each year. With this herd we are breeding for a certain phenotype that conforms to our interpretation of a breed standard. This means that the cattle tend to be larger than commercial or "commodity" cattle, have a proper color patter, have good pigmentation around the eyes and udder which reduces sickness due to sunburn, nice shaped head, smooth neck, narrow sloped shoulders, straight strong back, large depth of rib, be level from their hooks to pins, have a square hip, and exhibit a medium amount of bone in the skeletal structure. Additionally, we are generating a genotype that is measured through a tool called EPD's (Expected Progeny Difference), this is a data score that is generated using a central breed's database that keeps records for traits like growth and fertility of different blood lines.
Here is a heifer we have for sale:
We also have a herd of full Hereford cattle that are for club calf production. In a lot of rural areas of America, it is popular for kids to buy a steer or heifer in the spring, groom the animal and take it to competitions as they grow it out. There’s a bunch of different youth organizations that do this that you might have heard of like 4-H, FFA, etc. There are about 200 females in this herd, some are bred using AI, but the majority are paired up with bulls that we own. The selection criteria for this herd is nearly entirely devoted towards a certain phenotype once baseline standards are met. With these animals we are looking for more muscle, especially in the hind quarter, a more square composition, shorter rib, wider stance, and the ability to grow lots of fluffy hair. These animals look like this:
They probably look the same to you, but the heifer on top is a lot longer and much lighter boned. The steer in the second picture is built more like a box, has a lot more muscle in his hip, and with a straight shoulder like that, he won’t have as long a stride. The heifer will grow up to be a cow that can move really easily over long distances and can survive on little feed. The steer below only needs to live for up to 24 months, he will have every meal brought to him on a silver platter, and just needs to grow fast and look pretty. As an aside, the vertical D, M, underscore on the right hip is our brand.
We also have a herd of Wagyu cattle from Japan. This was probably our most challenging undertaking in that we had to take a small herd of seed animals and adapt them to our environment while still maintaining the aspects of the breed that make them desirable. Wagyu in Japan are the perfect example of single trait selection breeding. They have been bred for marbling, a trait which is controlled by only a couple of genes, along with a couple more that influence they types and amounts of amino acids that are produced. The first Wagyu that arrived on our ranch looked like some form of experiment gone wrong. A doctor in Oklahoma had done some sort of surgery on a minor member of the Imperial family and as a thank you had been gifted a couple bulls and 6 heifers. These had then been allowed to inbreed to the point that when we got them, they were about 30 head, many with cleft palates, unsound mobility, and just plain ugly. To grow the herd we out crossed those Wagyu with Hereford and angus cattle, this gave us what is called an F1 cross, 50/50 Wagyu. The best animals from that crop were then bred back Wagyu for an F2 which is 75%, then F3 which is 87.%, and so on. By F4 you’ve pretty much come full circle and have pure bred and now our herd is all F4 and above with all kinds of possible combinations, for example F3’s bred to F4’s, etc. If you’ve done it right then you’ve added in enough genetic diversity to get rid of the undesirable recessive traits and hopefully kept the traits for marbling. All in all, with bull lease programs and buy back options, there are about 2000 cattle in this herd under our control Visually, these animals now look like normal black cattle and they can survive in Nebraska. However they grow much more slowly, whereas it takes 18 – 24 months for a normal steer to get to slaughter weight, our Wagyu take 30 months and far less efficient at converting feed to meat. They taste much better though and so are worth a lot more money. Wagyu in Japan are raised in small herds, usually less than 10 animals, mostly indoors or in small grazing fields. They get a lot of individual attention so they don’t need the ambulatory, maternal, and survivability traits that we needed in Nebraska. We also bred the horns off of them because horned cattle are a pain in the ass to work with. A Wagyu cow looks like this:
She looks like a grown-up black version of the heifer in the first picture, small head, long smooth neck and shoulder (important for calving ease), straight back, long body, light boned. This photo was taken in July, she had a calf in May and hasn’t been given any supplemental feed since March but she’s pretty fat so she can handle the range pretty well. The difference in her and a commercial cow, is that her offspring will produces carcasses that are marbled like this:
The highest marbling grade given by the USDA is Prime, only about 2 - 3% of all cattle are graded Prime. Our Wagyu are over 99% prime, in fact they are off the scale in terms of marbling. When an animal does not produce a highly marbled carcass, we then remove those genetics from the herd.
Breeding for carcass quality is by far the most difficult of all traits. With the show steer herd, evaluation begins at birth, the offspring are sold within 6 months, and we can change what traits we are breeding for within a couple of breeding seasons. With the seed stock herd, the offspring are being sold at 1 – 2 years of age and it may take 3 or 4 years to react and bring about a genetic change in the herd. With the Wagyu, the evaluation doesn’t happen until the carcass is on the rail a full 3 to 3.5 years after conception, with 2 – 3 more calf crops on the ground, so it takes 5 – 8 years to make any meaningful breeding changes. We are keeping track of carcass data, tracking back to the breeding stock, and then making decisions that we won’t know are right or wrong for years down the road.
By the way, a good exercise on phenotype vs. genotype is the genetic determination of whether or not a calf will be horned, polled, or scurred. You’ve got dominant versus recessive, sex-linked, and the phenotype will only present for scurred if the animal is not horned. (Maybe a bit much for 6th graders)
Run-off is a big issue for feedlots. We have a very small (just a few hundred head) dry lot on the ranch which is a back grounding dry lot. Since it is not a finishing lot the concentration of animals and the type of feeds don’t present runoff problems. At the feedlot that we use for finishing, the utilize a lagoon system that catches runoff, stabilizes it through microbrial action, and then pumps it out for fertilizer on nearby crops. There are some pretty strict EPA requirements to minimize the chance of spillage.
Here is a pic of the feedlot outside of Burwell, Nebraska that we use:
The little dark dots are cattle. The big trapezoid shape at the top is the waste lagoon. Our feeder is also a farmer so he is using the runoff to fertilize his own crops which saves him money on purchasing nitrogen fertilizers. So there is a form of market-based incentive for the feeder to practice good environmental stewardship as the manure is a resource.
The issue I have to explain to people far more often than nitrogen cycles is carbon cycles. Ruminants do indeed produce large amounts of methane, which is a green house gas, however it is part of a carbon cycle that naturally occurs whenever plant matter is broken down by bacteria, whether inside an animal’s gut or decomposing on the ground. It is very different than methane pumped out of the ground which belongs to a carbon from a cycle that has been sequestered for millions of years.
Sorry, this turned into a book.
Jason P. Morgan
The Meat Guy on Amazon
TMG International KK
Nagoya 457-0822 Japan
Bonus! Follow-up questions.
You said that you keep close tabs on the genetics of your animals. I imagine you take blood samples and have them sent of to a lab. Since when have ranchers been able to do this? Has their been some sort of Bovine Genome Project? How has this changed ranching, breeding, and meat production since when only phenotypes could be observed?
It is possible to run a variety of DNA tests on cattle to determine if they are carriers of a specific gene or trait. But the technology is certainly not at the level where you could look at an entire genome and evaluate it. The technology is more often used to identify animals that are at risk of being a carrier of a specific detrimental gene. For example there was an Angus bull that was very popular a few years ago that, through semen sails, sired thousands of offspring. It turns out that bull was a carrier for a recessive gene that would cause calves to be born with spinal issues, usually resulting in a dead calf. Now if you want to sell an animal that has that bull listed anywhere in it’s pedigree, you need to have a test done to certify that it’s not a carrier. We don’t really have to worry too much about that, we focus more on highly heritable traits like calving ease. If one sire tends to throw a lot of dystocia issues, you don’t breed to him again and you purge your herd of those genetics.
Also, from your email, I have an image of a database where you keep track of all your cattle's family line, its and their genetics, observable phenotypical traits while alive, and quality of beef when slaughtered. Is that correct? Is this what the EPD is?
We have our own database for some traits include carcass traits that we use. However the EPD data base is maintained by the breed registry so it’s able to aggregate data from a blood line from all of the different ranchers that are using that bloodline. It’s all done through self-reporting and there is a lot of manipulation of data though.
With the inbred Wagyu, it sounds like the one breeding with the angus injects the needed genetic diversity to overcome the inbreeding and the subsequent F2, F3, F4 breedings are to get you back to 100% Wagyu. Is this correct?
My understanding of the process goes something like this...
The Angus provides the needed dominant alleles to mitigated the homozygous recessive genotypes that caused the problem phenotypes (cleft palette, etc.) in the F0 Wagyu. However, the genotypes that provide for the favorable Wagyu phenotypes (marbling, etc.) have to be bred back in while avoiding the problem homozygous recessive genotypes. The subsequent breeding of the F2, F3 generations accomplishes the former while selection of the most desirable offspring accomplish the latter.
Do I have this right?
That is pretty much how it works.
Also, I wanted to ask about GM beef. Does your family's ranch use GM livestock? Why or why not? What should I be thinking about when I think about GM beef?
There is no such thing as GM beef or any food animal for that matter. The technology is far too expensive at the moment and it’s likely that it always will be on a first generation basis. For example if they could modify a chicken to have four wings instead of two, while maintaining normal fertility, then they would only need to create a few GM hens and from then on just raise chickens like normal. But the benefit of the modification would have to really be game-changing, i.e. four winged chickens, to make this feasible. Plants are much easier to modify.
Another question, it seems that the cattle your family raises are largely grass fed and are free range. My impression is that is substantially different from most of the industry which use high density feedlots and uses corn feed. Any background on this would be appreciated.
Our operation is not significantly different than industry standards, except the scale is much smaller. Nearly all US beef cattle spend the majority of their lives free range and grass fed. The final finishing portion where corn is about 50% of the diet, with a mixture of other grains, and grass in the form of hay and other roughage making up the other 50%. Feedlot density is limited to how much feedbunk space you have and there is no such thing as an “overcrowded” feedlot. If you overcrowd, then not all the cattle can get to the feedbunk, and soon the feedlot starts losing money and going bankrupt. Most of what you’ve probably herd about the evils of CAFO’s and corn are the result of some extremely ill-informed pseudo-journalist/pseudo-scientists. Here some more reading on grass fed if you want http://themeatguy.blogspot.jp/2013/03/grass-fed-beef-its-probably-not-what.html
And as far as the waste goes... how does the handling of cattle waste compare to the handling of municipal sewage? Are the processes comparable? It seems like the cattle waste is not as treated as municipal sewage. What are the issues when it comes to waste?
I don’t know shit about municipal sewage. I flush the toilet and after that, it’s dead to me.
One final question. We have also when studying the energy pyramid in class. I've heard a lot from sustainability advocates that eating "down the food chain" is more sustainable than eating up it... that one kilo-calorie of tomatoes represents a much smaller investment in terms of water, land, and energy usage and has a much lower carbon footprint than a kilo-calorie of beef or chicken. What should I know about this?
I really like to deal with things that can be measured and though I’ve read lots of arguments from food “sustainability advocates”, I’ve yet to see anything based on quantifiable hard science. With a system far less complex, for example fossil fuels, we can measure with a pretty high degree of accuracy how much we’ve pumped or dug out of the ground in the last century, how much still remains, what rate we use them, what impact it has on the environment, and whether or not the temperature increase is going to kill us before we run out of oil. Even with all that science, it’s still pretty hard to determine what the yard stick is for sustainable versus unsustainable.
Agriculture, on the other hand is far more complex than just energy. From a calorie standpoint, yes, you can get calories more efficiently from eating corn, than from eating cows that are fed corn, if you were to conveniently ignore the fact that cows have the ability to turn a wide variety of indigestible cellulose into tasty and nutritious steaks. However, currently the largest threat to public health is due to calorie excess rather than deficit. So calories are a pretty poor yardstick. Nutrients might make a better measuring tool, in which case beef, which is one of the most nutrient dense foods we have, might do a little better, but even then, it’s really hard to measure and compare nutrients because there are just so damn many of them. Too bad we aren’t koalas, things would be much easier if we only had to keep track of eucalyptus leaves in and eucalyptus leaves out.
There are a few more issues with the “down the food chain” model. It ignores our ability to utilize animals as an integral part of environmental stewardship. It also assumes that food and agriculture are a closed system. That eating a pork chop means taking x kilograms of food and water away from some other eater. Actually, a lot of animal feed utilizes left over ingredients from other product streams. For example we feed distillers grains which are a by-product of ethanol production (which may or may not be a “green” form of energy, that’s an entirely separate, equally complex issue). Finally, this top down model fails to equate luxury food with other luxury items. Basically, anything more than a few greens, a few grains, and a bit of protein is a form of luxury eating. Just like anything more than a bicycle or scooter is basically luxury transportation. The philosophy behind “down the food chain” that I have so much trouble with is that it doesn’t allow for individual consumer desire for something beyond a subsistence diet. If we were to apply that thinking to all areas of human life, then the most sustainable way to live would be for all of us to be housed in large dormitory dwellings, wearing mass produced smocks, and travelling in big underground tubes to work (I may have just described Japan). Nobody really wants that so I think we need to look at food and judge it as we would any other luxury product. A steak should not be compared to a bowl of beans, a steak should be compared to a silk tie. Now if we only had some way to place a value on all the labor and resources required to bring each in front of the consumer so he could make an informed decision about which one to buy…In short, I get annoyed when the meat industry gets attacked for being “unsustainable” when industries like alcohol, or entertainment, or jewelry are not called upon to justify their use of resources to produce items that have no nutritional value. (For the record, I don’t think we should get rid of any of those things)
Final final question: the two pictures of the cattle you showed me looked exactly alike. Even after reading your explanation of the differences I am at a lose to tell the difference. How long would one have to work around cattle to develop an "eye" to discern these differences?
I don’t know, it’s probably a bit like language acquisition in that the earlier you develop the skill, the better your chances of fully being “fluent” in cow. There may be adults who, with no background in cattle, have learned to visually appraise animals, but I’ve never met any. Nobody ever goes into ranching, your either born into it or somehow grow up around it. I’ve been away for so long that I am definitely rusty which is very embarrassing when I go home. To a trained eye, the animals all look different and ones of higher quality jump out just like a pretty face in a crowd.
Congratulations/Condolences if you've actually read this far. Now go outside and do something.