I am starting a short series of posts that will describe some of the physiology, anatomy, and behaviour of the modern chicken. This has been done many times before, by people more qualified than I am….in greater detail….likely more accurately….and with far more authority. They are called textbooks.
The difference is, I am going to make it interesting, useful, and hopefully fun. Oh, and it will be in the english that normal humans speak. I also intend to explain some of the reasons why chickens are the way they are….how some of the attributes of “chicken-ness” are useful for the birds. The aim of the series is to give the readers some tools to problem solve issues that may crop up in their flock (pardon the pun…..see, entertaining all ready!). If you know how the guts of a hen works, you have an idea as to what might be going wrong when you see diarrhea or blood in the droppings. At the very least, it will give you another way to think about the way a hen works.
To start, I will talk about some of the striking factors that make chickens the way they are, and why they are that way.
Birds are strange creatures….feathers, eggs, hollow bones, no teeth, don’t produce urine, different red blood cells, all of which I will discuss later. All of these various oddities work together to allow one thing….flight. It seems like the vast majority of adaptations that the successful dinosaurs made revolve around the ability to fly. Feathers are lighter than hair, and insulate better. Bone marrow is heavy, and provides little structural integrity. Teeth are heavy, and carrying around a bag of urine inside your body definitely crimps your ability to soar. Red blood cells that have nuclei (the difference between bird and mammal blood cells) are more efficient at carrying oxygen and are quicker to produces…making bird blood more able to support the high metabolic rate needed to stay aloft. Getting the sugar shakes at 250 feet up is not an evolutionary advantage.
Chickens are omnivorous, able (and willing) to eat almost anything. They have a very short digestive tract (again, lighter), that is very efficient at extracting nutrients from whatever they put in their beaks.
Birds have lung adaptations, great eyesight, and lay eggs…..all of which make flight possible. (I am saying these like they are facts, but in reality, they might be adaptations that just followed along from their dinosaur heritage, and weren’t lost…..dinosaurs laid eggs and didn’t fly…..but it makes a good story, and is plausible).
Anyways….I will be developing the truly informative stuff over the next little while. I hope it is useful to you, and gives you a different way to look at and evaluate the way your hens interact with the world.
Mike the Chicken Vet