Handling Heat

As everyone knows, we've been in quite a heat dome for the last couple of weeks.  Looks like it might break over the weekend, but many people wonder how our animals at Polyface fare in these kinds of heat cycles.  After all, we don't have air conditioning out in the field.

Before I go through the different animals, let me offer three foundational principles that separate us from Concentrated Animal Feeding Operations (CAFOs) like Tyson chicken houses or Smithfield hog factories.

One, scale matters. It does matter whether you have 5,000 in a group or 500. Or in the case of our broilers, 75.  

Dissipating heat in a bigger, crowded room is much more difficult than in a smaller, less crowded room.  That's just simple physics.  

Here at Polyface, our animals are in small groups.  Although we have some significant numbers, they are in small groupings.  Our pigs, for example, are in groups of 50.  Our broiler (meat) chickens are in groups of 75.  That makes a world of difference.

Second, ventilation means everything.  And it's much easier to adequately ventilate a smaller structure than a large one.  

Opening a window in a small room has a bigger effect than opening a window in a large room.  Again, that's just physics, but it has significant practical implications on comfort.  

We're the only farm in the area without sides or walls, even on our barns.  Lots of breeze through there.  Field shelters offer shade without complicating side walls.  The little squatty broiler shelters have walls for cold times, but during the summer, we remove the back panel to make it a breezeway.  Being small, these shelters cool down nicely.

Third, contact with the ground makes a huge difference.  

If you've never done it, go out and find a spot with unmown, thick vegetation on it.  Part the grass and weeds and feel the ground underneath.  Well-covered soil, either with mulch or vegetation, is always cool to the touch.  Uncovered soil, either through overgrazing or tillage, absorbs sunlight and gets hot to the touch.  

Because Polyface pastures livestock on heavily vegetated fields, the animals enjoy lounging on cool and often damp ground.  That coolness vectors up into their bodies, providing significant relief from the heat.

With those three overriding principles in mind, let's go through each of the animals and explain how they deal with heat.

Cattle: Cattle like shade, so we use both trees and portable shademobiles to offer them comfort. But there's more.  

Because they are in small paddocks moved daily, they are never far from water.  The water trough is always nearby and clean; they don't have to walk a mile to find water, and clean means it's delectable. As a result, going to drink is easy. Accessibility means they don't wait until they're really thirsty before getting a drink; it's always close. Cows will drink some pretty funky water, but they don't like it as much.  Good, clean water makes them happy.

At Polyface, we've been selecting heat-tolerant genetics for a long time.  When you visit, you'll see almost no black animals.  The hide of a black cow versus any other color--red, grey, white--can be up to 40 degrees hotter on a hot summer day.  Black absorbs the sun's heat.  That's a lot of heat to dissipate, so hide color matters.  

Most of our cows now are some semblance of red since we're using South Poll bulls.  The South Poll breed is the fastest up-and-comer in the grass-finished movement due to its heat tolerance and short, squatty phenotype.  Developed over a lifetime by Teddy Gentry, of Alabama country music group fame, the breed association prohibits showing their animals in 4-H and FFA livestock shows to keep growers from being tempted to feed them grain for plumpness.  The breed is really committed to grass finishing, and they do great in the heat.

Because we move the cows to new paddocks daily, the paddock they enter has long, thick vegetation and, therefore, inherently cool ground.  The ground doesn't heat up immediately after they've eaten the vegetation.  By the time their pruning results in warmer soil temperatures, they've moved onto the next day's paddock plate.  The daily move onto lush pasture provides cool lounging denied most cows in America.  Polyface cows receive special treatment.

Pigs: Pigs don't sweat, so for them, the heat is especially uncomfortable.  They can also sunburn because their hair isn't heavy like cow hides or chicken feathers.  Their skin isn't as naturally protected as other animals. 

Here at Polyface, pigs either have shaded woodland paddocks or thick, deep vegetation pasture paddocks similar to our cow pastures.

Of course, a pig's favorite cool-off procedure is to make a wallow.  Imagine shoveling out a shallow depression in your yard and filling it with water.  Pigs make over-sized mud puddles by rooting out a depression, scooping the dirt up on the sides, and letting it fill with water in a rain.  When they wiggle in the mud, it becomes more impervious and holds water better.  Pigs are experts at this and can make sand hold water.

The combination of water and mud provides cooling as well as protection from sunburn.  

Some people pay big money for facial mud masks at chic spas.  Polyface pigs adorn themselves with these skin-healing mud packs on their own.  Nearly all our pigs make wallows in their pasture paddocks.  If the heat is accompanied by extreme drought, drying out the wallows, the pigs dig furrows to lie in.  The soil is cool; when they dig a trench, they get down into the cooler layers and stretch out in that groove.  It's quite amazing.

The pigs know exactly how to cool off and protect themselves from the sun.  Most of the pig pastures at Polyface are silvo-pastures, meaning they have widely spaced trees with grass underneath--kind of like a park.  We use portable shade structures, topped with greenhouse nursery shade cloth, in the paddocks without enough protective trees.  Pigs in industrial confinement factories can never dig, never lie in a trench, never build a wallow.  How sad.

Laying hens: Polyface laying hens are provided either our Eggmobiles or Millennium Feathernets.  In both cases, air movement is profound due to the design.

Eggmobiles, which follow the cows, have a slatted floor and a two-foot chicken wire window around the top.  The combination of openness on both floor and ceiling creates natural convection to duct air up, through, and out.   Of course, the chickens also have the option of lounging on the cool ground underneath the eggmobile since they roam free.  In a traditional industrial factory house, tens of thousands of chickens are crammed in multi-tiered cubicles in a confinement house where ventilation comes from fans.  No natural air movement.

The Millennium Feathernets are on skids with an A-frame structure that also naturally draws air through.  The high peaked roof and eaves roughly 3 feet off the ground create a natural drawing action, sucking air in under the eaves and ducting it out the peaked roof.  No matter how hot the day, this structure always has a nice breeze. On a hot day, it's probably the most comfortable spot on the whole farm, except for the forest.

In both of these models, water is close and accessible.  Hydration is easy.  And, of course, the birds enjoy the cool ground under a dense grass cover.  This is all a far cry from the fate of factory chickens crammed in houses with no soil, no vegetation, and no natural breeze.

Broilers: Meat birds never reach complete adulthood like other animals.  They are processed while they're nice and tender.  As a result, the bulk of their life is very young.  Chicks love 90 degrees--that's how hot we keep their brooder for the first couple of weeks.  It simulates a mother hen's temperature covering her young.

When they go out to pasture around three weeks old, they are still extremely small and can handle almost any heat.  Again, because we move them daily, they enjoy that cool ground to lounge on, so it helps to regulate their shelter temperature.

Heat only becomes a problem in their last couple of weeks, as they get larger and more bulky.  Their little field shelters, with only 60-75 in each one, ensure small groups.  With the back-side panel removed, the aluminum roofing reflects heat and creates natural convection through the shelter.  Even on a still day, you can feel the breeze sucked through and over the birds as they lounge on the cool grass.

If it gets insufferably hot in their last week, we pour some cool water on the top of the shelters.  A splash of water on the aluminum roof drops the temperature inside dramatically, like a thundershower.  The industry doesn't want you to know how many birds they lose in a heat wave, but over my lifetime and knowing growers, it's a lot.  Their environmentally controlled houses are NOT trouble-free and don't provide the comfort designed in nature

In small groups, outside, in pastures, with natural ventilation, the birds have a much higher chance of being comfortable.  And we can monitor these small groups better than you can a house full of 20,000 chickens.  Polyface methods win again.

Turkeys: Turkeys generally run on pasture in groups of 400-800, with shadecloth and roosting trailers we call Gobbledygo.  We move them every couple of days to a new oval created by electrified netting.  The portable fence keeps the turkeys in and predators out.

Turkeys have a higher heat enjoyment tolerance than any of the other animals.  As a result, they are the least uncomfortable in a heat wave and generally don't require any special treatment to stay comfortable.  As long as they can shade up under their Gobbledygo, they're happy.  Industrial turkey houses, in contrast, have many electric fans in an attempt to rid the air of fecal particulate being inhaled and provide the airflow we find in nature. At Polyface, passive breezes and the great outdoors change everything for these gentle birds.

One final point: all animals sometimes pant as a way to cool down. I was out this morning running the chainsaw, and I was panting.  

Nothing is inherently abusive or unkind about panting; it's a natural response to heat and has been designed as a way for humans and animals to cool themselves. Here at Polyface, if and when any of our animals ever pant, at least they aren't sucking in fecal particulate that creates open sores in their tender mucous membranes.  Deeply breathing the fresh, crisp, sun-soaked mountain air? That's a game-changer. 

Also, remember my point about smaller groups of animals? By keeping our animals in smaller groups, it's not only much easier for the animals to stay comfortable, but also much easier for us to check on them and quickly provide extra temperature relief when needed.

Thank you for taking this little info-walk across our pastures on a hot day. You should come visit and see for yourself sometime. Even on the hottest day of the year, you can enjoy the woods and the deep, lush pastures just like us and the animals we lovingly raise. 

Be assured that although heat affects us all, here at Polyface, we're doing all we can to keep our animals stress-free and happy.  

Thank you for caring about how we grow your entre.

Joel