What is the Immune System?

What is the immune system? Let’s look at its parts and organs in a fun way to remember.

Most of us think only of the lymph nodes, vessels and ducts (okay, well maybe that was just me) but there are several players.

Dog immune system organs include the spleen, thymus, tonsils and adenoids.

Another important player is bone marrow. I'll explain in a minute.

While my website is about dog health, dog nutrition, canine health problems and the like, we have all the same basic parts so I can safely say, what is good for the dog is good for the dog owner (okay, except raw meat).

I'd also like to think my readers will, after seeing healthy changes in their canine companions, opt to make some changes themselves.

Anyway, back to facts about the immune system.

The only thing worse than reading boring stuff is writing it, so lets make it a bit more fun. To answer what is the immune system, we will look at the body as irreplaceable prime real estate (it is!) and the parts of the immune system as a vast army set up to protect it.

This army must protect this prime real estate from invading forces of viruses, bacteria, toxins, free radicals, parasites, plus, provide cleanup and maintenance.

The first lines of defense are a thick wall of skin (which is an organ too) and the forming of mucus in the eyes, nose and mouth to lasso those bad guys and carry them away. If they sneak into the stomach, there is strong acid to do them in. Dogs have an advantage in that they can kill bacteria in their mouth (which is why they can eat raw meat).

What is the immune system army? There are different types of soldiers. Raised within the immune system organs and sent off to battle through the clear fluid of the lymph vessels, they conquer the invaders and clean up the battlefield.

What is the immune system army camp? Here are the major locations and what they do:

The Lymph Nodes

  • Produce and store the soldiers
  • Are a clean-up station. As lymph fluid passes through, bacteria and organisms are filtered out and destroyed
  • As the fluid leaves, more soldiers are deployed through that fluid

The Spleen

  • Also produces soldiers
  • Removes old red blood cells and abnormal cells
  • Removes microbes and debris from the bloodstream

The Thymus

  • Produces soldiers
  • Protects against autoimmunity

The Tonsils

  • Produce soldiers
  • Trap germs and kill bacteria entering the mouth

Bone Marrow

  • Produces soldiers

What is the immune system soldier and what is his job? Here is a list of soldiers and their specific missions.

  • Phagocytes: soldiers who search and consume bacteria, viruses and dead or injured body cells
  • Lymphocytes: White blood cell soldiers who move to every organ of the body. In their ranks, specialists are:
  • Helper T-cell soldiers drive and coordinate the army, activating B-cells and Killer T-cells
  • Killer T-cells (self explanatory)
  • B-cells devide and produce antibodies to destroy antigens, neutralize toxins and incapacitate viruses
  • Memory cells remember exactly who invaders are so if they attack again, they will be wiped out much quicker

The immune system is designed with a natural defense weapon which has the ability to distinguish between the body's own cells and foreign invading cells - as long as it's healthy.


The Whole Body Works Together

While the immune system goes about its search and destroy mission, if the dog digestive system is malfunctioning, the immune system will even reject nourishing proteins unless they are first broken down by the digestive system into their primary, non-antigenic building blocks.

One thing many of us don't understand is a dog on the same dog food for years will develop health problems beginning with digestion because his body is just plain worn out from trying to convert highly processed food. In that case, changing from one brand to another won't help unless it's a vast improvement.

Take a peek at Dog Food Manufacturing to see what I mean.

Now if you haven't been there, check out the digestive system.

What is the Immune System to Dog Digestive System

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