Classic Large White Sow

Yorkshire Sow

Charlie has the classic Large White a.k.a. Yorkshire pig form. She’s long. She’s big. She’s great on pasture. She’s a wonderful mother. Charlie, along with two other sows, farrowed in the south field greenhouse which is an open shed, not to be confused with the new larger greenhouse we’re building this winter. Greenhouses as in lots of light yet still wide open for lots of fresh air.

Charlie has that classic “Pink Pig” conformation that is so commonly associated with pigs. Yorkshires are one of the oldest breeds of pig, originating in Yorkshire England. They are a true heritage breed and one of the most successful breeds, having been used as foundation genetics for many other breeds and for modern swine husbandry.

Unbeknownst to most, a breed is not a breed is not a breed. Uniformity varies even within breeds for factors that are not designated as the breed characteristics. Within any breed there are those who have been selected into essentially three lines: Show pigs who get fed and bred to meet the specifications of the show ring; confinement pigs which have been selected for performance in confinement on generally a grain diet that has led to reductions in how well they can digest forages in favor of grain diets; and pastured pigs which are those that still have the original genetics for thriving out on pasture without the need for high calorie grain based feeds. Because of selective pressures of breeding within each of these system of management the lines of genetics within a single breed can diverge significantly such that while a Yorkshire for show may look, to the untrained eye, like a Yorkshire for confinement like a Yorkshire for pasture but each of them will have been specialized for their specific system.

A simple example is that within confinement operations breeders purposefully select away from sows that demonstrate nest building behavior because in confinement conditions this comes out as tail biting, aggression, agitation, bar biting and other destructive behaviors that are undesirable when you have 3,000 sows housed in a big building. As a result these confinement line sows have lost the ability to reproduce without farrowing crates. The sows have lost the ability to build proper nests, to be attentive to their piglets and to not crush piglets. The breeders have created a line of pigs that can not reproduce naturally without unacceptable losses. Take away the farrowing crates and the entire confinement industry is faced with the necessity of changing it’s genetics to regain mothering ability, a process that takes years.

Pastured sows farrowing out in the brush retain these mothering behaviors so they build good nests, pay attention when a piglet squawks and avoid crushing their piglets. The piglets themselves also have better survival instincts which help them move away from the sow when she is rearranging the nest and then come back when she’s ready. A pastured sow that fails to do good mothering has fewer offspring as a result. She also is more likely to get culled on a pasture based farm for not being a good producer. Conversely, a sow that can produce many offspring without intervention on pasture is going to both be kept to breed another cycle and more likely to have descendants who pass along her mothering ability. We select hard for good mothering without the need for farrowing crates or other interventions. Thus no gestation or farrowing crates are needed for sows with good instinctual mothering behaviors found in the pastured pigs. Behaviors that in a confinement situation create problems are beneficial out on pasture.

Another example of the difference in selection between show, confinement and pasture lines is that a pig which grows fat on a high calorie diet is culled in confinement or the show ring because they want “The Other White Meat” which is lean. That same pig may be able to put on weight on a lean pasture diet maintaining their condition even through winter, farrowing and nursing without commercial pig feeds or high calorie grain feeds. Conversely, the pig who is selected for in confinement to stay lean is unable to thrive on pasture because it can’t get enough nutrients from the sparser pasture diet. Each of these three environments, show, confinement and pasture, select for a slightly different pig. Thus the differences in lines.

Selection can be even finer: Because of our cold winters and year round farming schedule we farrow even through the winters. Only the best sows farrow through the winters. We call these winter sows and Charlie is one such sow. She comes from a line of sows, her mother, her grandmother and back for many generations on our farm, all of whom have shown progressively better winter farrowing ability. Charlie farrowed at night in 4°F weather. The south field shed is an open shed. She could have chosen to build her nest back inside the shelter but like almost all of her line she builds it out at the edge where she gets full sun. They are perhaps seeking the drying and sterilizing effects of the ultraviolet as well as the sun’s warmth. A dry nest makes for better piglets. Our cold dry winters are actually better than the warmer mud season in this regard. As a result of over a decade of selection we have sows who now farrow well even in cold weather without farrowing crates and without heat lamps. Things that help are her deep bedding pack nest that generate belly heat, the fresh air (don’t close them in), a good wind block and plenty of light. Thus why we’re building the new larger greenhouse which will be open and airy just like the south field shed but have even more light instead of the mix of bright and dark roofs on the south field shed.

On the other hand, Three years ago we got some new genetics and I’ve been having to weed them. Those sows lack the ability to farrow well in winter. They produce smaller litters. I term them summer sows. We’re now into our third generation of those genetics and I’m gradually improving them, they’re our Tamworths, but they still have a long ways to go before they catch up with our other breeds and cross lines who both thrive through the winters and farrow excellent litters through even in our coldest weather.

So why do I have the Tamworth line? Teats. Within that line I found genes for extra teats and I’ve been able to rapidly raise their count from 16 to 18 teats, even 18 teats on a boar and that matters because how many teats he has is an indicator of how many teats his daughters will have. More teats means more milk and more spaces at the milk bar. This is an example of a line within the breed (Tamworths) which had something a little different about them. Gradually I’ll shift those genes over into our other cross lines. It’s a process that takes years, even decades.

Of course, genetics isn’t everything. There’s more than just good genes for instincts and form. In addition to the genetic specialization that comes with selective breeding pressures there is also a learned aspect. Piglets who grow up on pasture learn to eat pasture at the snout of their sow. Piglets from show or confinement when dumped on pasture may have no idea what to do with all that green, which forages are good to eat and which should be avoided.

Selective pressure is a powerful force. If you took a population and forbid explicit graphic representations depiction certain forms of art hundreds of generations you might actually cause a change of genetics, a fundamental alteration of the brains of long standing members of that group which would result in the loss appreciation and sense of humor related to these types of illustrations. Individuals within this group might have a great deal of difficulty understanding that other cultures highly value cartoons. Selective breeding is a very interesting tool whether in the hands of man or Mother Nature. Evolution works, intentionally and sometimes not so intentionally. Be very careful what you inadvertently select for while aiming for your goals.

Breed provides an overall conformation – e.g., Large White pig with a long body and upright ears – but the line of the pig can be even more important when considering what to raise on pasture. Pasture has a specific set of conditions which are different than CAFOs, confinement animal feeding operations, so it takes good genetics to produce good pastured pork.

Also see:
Lard vs Bacon Pigs
Pig Page
Four Sows and Pigs

Outdoors: 7°F/-12°F Sunny
Tiny Cottage: 64°F/58°F

Daily Spark: I have a firm rule: never diss someone’s choice of religion or breed.

About Walter Jeffries

Tinker, Tailor...
This entry was posted in Uncategorized and tagged . Bookmark the permalink.

11 Responses to Classic Large White Sow

  1. Kate says:

    Great post. Scarey what we are doing to animals through factory farming! I love the idea of your winter sows snuggling in with their piglets in the sun and snow. Hope the 25 below weather hasn’t harmed them.

    My questions: I raise a couple pigs a year, the piglets come from a small farm where the parent live outside on grain & garden scraps. I feed the piglets lots of whey and garden scraps but still need to give them grain – or do I? Their pasture is big enough that they tend to dig up about half the space while the other half remains grass (an old hayfield). If I cut down on grain would they naturally gravitate toward the pasture? I’ve only been raising them for a couple years so I don’t think I would be able to tell if they were stunted unless it was dangerously obvious. If you have any suggestions for me I’d appreciate it.


    • First thing is set the pasture up for managed rotational grazing so that it has a strong perimeter fence and many paddocks. See this post. More smaller paddocks is better than fewer larger paddocks. Read more about managed rotational grazing on the Pig Page.

      Next, start shifting the grain supplement later and later in the day. Then experiment with decreasing the grain amount gradually and seeing how the pigs do once you’re feeding it at the end of the day. It’s a adaptation and experimentation process. Without knowing the genetics it’s hard to say but since the piglets are coming from a farm on pasture that lends them toward the direction you want.

      You have nice boxes at your web site.

  2. vikki says:

    You mentioned specifically that you brought in new genetics a few years ago. Does this mean that, other than that instance, you normally do not bring in new genetics/animals and operate a largely “closed” herd? I’m interested in starting a sheep farm and running a closed herd, but I’ve been having difficulty finding information about the minimum number of individuals that are required in order to prevent genetic defects due to a small gene pool. Any ideas?

    • Correct. We have multiple herds and an essentially closed farm for our pig genetics. That means we very rarely bring in new genetics. We can do that because we have multiple herds and thus multiple genetic lines through a wide selection of animals. Having a closed herd means better control over our genetics as well as better biosecurity – keeping disease out.

      There is research that is mostly based on math that says a single line closed herd will have genetic problems within ten generations due to reductions of about 10% per generation in fertility and other things. But, that research is not real world, it’s based on math, and it fails to account for two things: 1) starting with good genetics – the math assumes randomness; and 2) failure to select and cull hard – the math assumes random pairings. In the real world Mother Nature and the farmer both can select very hard. Only about the top 5% of our females get to test as breeders and only about the top 0.5% of our males get to test as breeders. Virtually all of our pigs get culled to meat before the get to breeding age. We breed the best of the best and eat the rest. This high culling rate, this high selectivity changes the math and the reality of the practices.

      As to the problem of ‘preventing genetic defects’ realize that genetic defects do not spontaneously appear. They need to be in the subject population. Even with a large population they can be a problem if they’re prevalent. The first thing you need to do with any population is explore what genes you have and then start weeding out any bad genes. Bad genes, those that will cause genetic defects, are generally recessive which makes the process more interesting.

      Once you’ve identified your genetics, the pegs you’re working with, you can start managing them by weeding out, culling, the bad genes and concentrating the good genes. It’s a very long term process that takes years, decades. Breeding is fun. Be in it for the long haul.

      Breeding and genetics is much like the game of MasterMind but with thousands of peg colors. One of the great things about pigs, which is why I use them for genetic research, is that they breed at a young age, producing many offspring per litter and many litters per year. This makes it much easer to determine what the genetics are like and weed. Plus, the culls are delicious. I like sheep, I enjoy raising and eating them too, but they reproduce so slowly that it is much harder to tease out the genetics.

      That does not answer your question about how many animals are the minimum herd size. With sheep it will be more than with pigs and you’ll want to run multiple herds so you can have multiple rams. This is where registration organizations come into their fore by pooling the knowledge of many farmers together into a record of what various animals produced. A good registry organization’s goal is producing better, more productive livestock. That’s why the registries originally were developed so long ago.

      The general rule of thumb with slow producing populations which I have heard is about 300 individuals being the minimum sustainable breeding population. They say that all Cheetahs are descended from a single pair and that all humans are descended from about fifty women – look where that got us and them today…

      • LJ says:

        Very interesting post. I’m wondering how a slow producing, limited gene pool such as your dog pack gets around the problem of the minimum sustainable breeding population? Do you bring in new dogs periodically? Are possible genetic weaknesses naturally culled out when only the top dogs reproduce?

        • They are long lived and have brought in new members as well as members exiting outward into other packs. They have exchanged with other packs over the years. Additionally, in a pack there typically only a single breeding pair at any one time and our pack seems to follow this rule. The rest of the pack operates in a supporting role. This is typical pack social behavior that means that most pack members never breed, perhaps self-culling. The breeding pair is the Alpha pair.

  3. vikki says:

    Wow! Thank you, that is a fantastic response. I’m glad to finally have a number, because it’s about an order of magnitude bigger than my existing plans. I’d rather know now so I can reevaluate and either attempt to adjust or scrap those plans. Thanks again!!

  4. Eliza Gray says:

    Hi I have a question:
    I bought 2 gilts and a boar 6 months ago Now I believe they are around 6 to 7 months old.

    the girls breed are Yorkshire/Hampshire/Tamworth/Chester white/DUROC
    the boar is Yorkshire/Hampshire/DUROC

    I just weighed the girls yester day as of 1/18/2015

    Maggie my long black pig weighed:340lbs
    Lisa her sister who is pink with blue weighed in at: 300lbs
    Parents)(father weighed in at 650lbs) (both mothers weighed 550lbs)

    Maggie my black pig is more of the dominate girl in the group but sweet about it they all snuggle up in the big house together it is so funny. but I was curious if you though this was a good size in pig at there age they get fed 3 times a day with grain and all stock and then in the spring time when there is more produce around I feed them a lot of veggies and some noodles from are old food selection LOL which they go nuts for.

    • Since I don’t feed a corn/soy based commercial hog feed diet with those genetics I can’t say from experience. Based on the Garth Pig Stockmanship Standards book’s growth chart on page 18 it looks like it is possible.

  5. Linda says:

    CAFOs are awful along with other factories that produce all of our meats, veggies ect. This is a big reason why I am raising my own food for my family. As someone who does animal rescue I cannot in good conscious support that. Then of course I get some people who think it is horrible I am a rescue that raises food, they just do not understand how horrible the conditions were of the food they are eating had to live in. Maturing to slaughter weight without having known one good thing, at least pastured animals are spoiled and get to feel the sun on their backs and grass under their feet and know happiness first. And of course are put down quickly and humanely never knowing fear or pain.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.