It’s a summer Saturday morning and you’re headed to the farmer’s market or ordering from your local food market. Eggs fresh from local farms are at the top of your list. You haven’t seen many lately when you’ve gone to do your shopping. You take a look around and see very few eggs. ‘Where have all the eggs gone?’ you wonder in dismay. You just saw plenty in the grocery store the other day. Why aren’t they available locally?
It’s a common problem in the summer. The main reason: heat. Especially here, in the south. Now before you start to tell me that plenty of large corporations have their laying hen operations in the south, let me explain. The eggs supplied to the local farmer/food markets are produced by local farmers, not by large corporations, which is why you chose these platforms to buy your food to begin with, right? Let’s take a look at what’s going on.
Heat stress is what happens when body temperature increases beyond what the body can control. Body temperature can increase as a result of eating, exercising, environmental temperature, stress, and many other things. To maintain homeostasis (a balanced state within each of us that allows for body processes to function normally), the animal must adjust what he/she is doing to keep body temperature from rising too high or falling too low. In these situations, you will see the birds change their behavior. They may eat less, drink more, move less, and so on, to keep their temperature from rising. Why is it so important that temperature stays in the bird’s defined limit? To survive is one reason. In the most severe cases, temperatures too high or too low can cause death. However, even at lower severity, there can be consequences of having an increased body temperature for a sustained period of time. In the animal production world, these things include reduced production of agricultural products (e.g. eggs, milk), slower growth rates in animals being grown for food production, and a reduced ability to reproduce. All of these things, if left unchecked, can cost the producer and, in turn, the consumer, money. For the purposes of this article, we will focus on how reproduction is impacted by heat stress, since that is what egg producers depend on for the production of eggs.
Chickens are most comfortable between an environmental temperature between 60 and 75o F. As the environmental temperature increases, body temperature begins to increase and the hen must do several things to reduce her body temperature. She will start to pant, the open mouthed breathing that brings dogs to mind. The respiratory system of the birds helps remove heat with each exhale and bring cooler air in with each inhale. However, this only works to a certain extent, once the humidity gets too high, the respiratory system loses its effectiveness in cooling the hen in this way. You will also see her holding her wings away from her body and ruffling her feathers more often. This is allow airflow into the space between her body and wings and underneath her feathers so her skin can be cooled.
In addition to doing these things, she stops doing the following: eating, moving around, and producing eggs.
The process of eating and digesting food is a metabolic process. As we all know, food contains calories. The definition of a calorie is the amount of energy needed to raise the temperature of 1 gram of water 1o C (or about 34o F). The foods we (and chickens) eat have energy (in the form of calories) and as they are digested that energy is released, increasing our body temperature. The primary protein source in poultry feed is corn. You may have previously heard corn referred to as “hot”. That’s because corn has a lot of energy packed into those little kernels! So it makes sense that when chickens eat, that corn can really increase their body temperature. So how do they work around this? They stop eating. The less food they take in, the less their body temperatures will increase while digesting the feed.
With less nutrients coming in you will likely observe reduced movement from your birds. As we all know, we have to fuel our bodies before we can expect them to work. The reduction in movement is necessary because with less calories coming in, there are less calories to burn. They just don’t have the energy to burn with unnecessary movement and need to reserve what energy stores they do have for important things like heart and lung function. Exercise also increases our body temperature as muscles heat up and glucose and fat stores are used for energy. So not only are the hens not eating enough, but everything they do requires energy to be used and the chance for increased body temperature. So, on a hot summer afternoon, you will often find hens in a nice, cool spot lounging in the shade so they can avoid increasing their body temperatures any further.
However, the reduction in feed intake is really what leads to reduced production of eggs by these birds. They just don’t have the energy or nutrients to produce eggs. With reduced food, there are reduced nutrients to make parts of the egg, like calcium for the shell. If production were to continue that calcium would be pulled from the bones of the hens to make the shell and, biologically, that is not in the best interest of the hen. The body will reduce all nonessential processes until body temperature can be maintained. Ovulation followed by the production of an egg, is one of these nonessential processes. When my hens started laying again, after having the low light season of winter off, I was getting 12 to 13 eggs a day! Now, in early August, I am getting two or three, from the same number of laying hens. It’s just too hot for them to do everything and staying alive is more important biologically than producing an egg.
At this point, you’re probably thinking, “But the grocery stores still have eggs.” Well that’s a good point. Commercial laying hen operations are vastly different from our local egg producer’s operations. Commercial laying houses have environmental control in their barns. They can set the barn at an ideal temperature and humidity. Cool cells that use air blown over a water soaked cell keep the chickens cool. These cool cells keep the hens cool in the same way humans do when they sweat, through evaporative cooling. Anytime the temperature gets a little too hot in the laying house, the thermostat kicks the fans on and they pull air through the cool cell, across the house, to reduce the environmental temperature.
They also have a constant, indoor water supply so cool water is also available. Commercial operations are set up to negate the effects of heat, avoiding the decrease in egg production, and as a result still provide plenty of eggs to supermarkets. Oh, and they have thousands of birds laying eggs daily.
Local producers, however, are set up a bit differently. Chickens are kept outside and are given shelter from blistering winds in the winter and shade from the sun in the summer, but these shelters aren’t equipped with the technology to control the environmental temperature as I described above. Misters are often used in these coops to help keep the hens cool and in production. However, when temperatures and humidity get as hot as they have been lately, these fans and misters can’t keep up. Another idea is to give your hens a kiddie pool! They’ll hop in and walk around!
Plenty of shade and airflow are provided where possible. Fans are a great way to help with airflow.
Another great thing producers do to keep their birds cool is to give them a good, cool place to take a dust bath. These places are under a tree, or your porch, in your landscaping, or under any shaded area in your yard. The hens will scratch up the dirt to make it loose and then roll around in it. The cool dirt helps lower their body temperature, plus the dirt gets under their feathers and helps keep them mite free!
While cool water is supplied just as bountifully as in commercial operation, without an automatic watering system, it can get challenging to have cool water at all times. However, local producers are inventive people and will give their hens ice water or frozen treat blocks to help keep their hens cool.
Cool fruits and veggies are a great way to help keep you hens cool, too!
Your local egg producer can have anywhere from 20 to 800 laying hens, not thousands, so when one or two cease laying because they’re hot, both the producer and the consumer see that impact.
When looking for eggs in the hot summer months, know that local producers are doing the best they can to keep their hens cool and healthy and that soon enough, eggs will once again be plentiful.