Pigeons pass immunity to their young in two ways, first through the egg and and a second time in the pigeon milk. For the first nine or ten days of a sweaker's life, they receive pigeon milk from their parents. Along with essential nutrients, the parents are also passing immune factors to their young in this milk. In order for the youngsters to accept and utilize these immune factors, their intestinal lining must be what I call "leaky". Probably a better terminology would be that the intestinal mucosal barrier is immature or under-developed.

For lack of a better word, we will use "leaky" to describe the intestinal lining's ability to allow parental immunity to pass through the lining and into the blood stream (and associated lymphatic tissues). For protective purposes, at about nine to ten days of age (when pigeon milk is being replaced with seeds), the intestinal lining of the youngster "hardens". This happens for two reasons; first, since the pigeon milk is being replaced with seeds, there is no longer a need to allow the passing of parental antibodies and their associative immunoglobulins through the youngster's intestinal lining. Secondly, the intestinal lining must now prepare itself for the mechanics of solid food digestion.

So, as the youngster matures, it begins to receive seeds from the parents and it begins to explore its environment by pecking around the nest. At this time, the likelihood of ingesting pathogens which are present in the loft, greatly increases and in defense, the digestive lining of the youngster begins "hardening" in order to seal out (as well as possible) pathogen contamination from passing through the gut wall (intestinal epithelium) into the internal environment of the youngster's body (internal circulation, tissues and organs). Also, this "hardening" becomes necessary because the youngsters must begin to produce digestive acids to assist in the break down of solid foods, like seeds and grains. Therefore, mucosal secreations which will lubricate and protect the intestinal lining, from these digestive acids, must be produced during this hardening process.

Basically, as the intestinal mucosal barrier matures, it provides a first line of immune defense against pathogens and provides a mechanism for the proper processing of ingested antigens. The mucosal barrier contains specific immune defenses including mucosal antibodies (immunoglobulin classes; IgA, IgG and IgM). A healthy mucosal barrier defense contains sufficient antibodies and responds to normally encountered antigens, dealing with them appropriately. Secreations of Immunoglobulin class A (IgA) are the predominant antibody protection found in the mucosal immune system.

"Hardening" of the intestinal lining has several aspects. For now, I will point out that when the youngsters are receiving pigeon milk and parental immune factors, two condidtions exist: the cells of the lining (intestinal epithelium) are loosely packed which allows the immune factors to pass between the cells and into the internal circulation of the youngster. And, the mucosal barrier (anti-pathogen or protective secretions that offer a first line of defense) are very thin and allow mostly unobstructed passage to the surface of the intestinal epithelium layer. When hardening takes place, the cells of the lining "tighten" sealing off access and the secretions of the mucosal barrier thicken and become rich with antibodies and other defenses which inhibit pathogens from attaching to the intestinal lining and from colonizing the gut.

You may be asking then how is the youngster protected if these defenses are looose and thin? The babies are protected by the protective secretions found in the parents pigeon milk. Most everything the baby will need to protect itself is found in the pigeon milk. So, the pigeon milk protects the youngsters in the early days of its life and also passes immune factors to the youngster. The youngster's own "learned" defenses will start to take over as the milk source is being slowly removed.

As a breeder, you walk a fine line. If you medicate your breeders just before or during egg production, you run the risk of lower counts of parental antibodies in the egg sack. This can lead to insufficient immune response in the youngster when hatched. If you medicate your breeders while they are giving pigeon milk to their young, you run the risk of damaging the youngster's "leaky" intestinal lining and the mucosal barrier, during this important transferance period, when the youngster must receive parental immunity factors, in order to build up and "teach" its own immune response.

What is a breeder to do? More and more, products are coming out that are called "Immunity Builders". Not all of them are, some are just "cashing in on a terminology". However, Max Immune Plus and Show Stopper are two "All Natural" Immunity Building products that offer breeders a safe means of keeping your birds healthy without the need for medications or antibiotics.

We also have a new product, called "Baby Booster Pills", which can be used during that stessful period when youngsters are being weaned off of pigeon milk and onto solid foods. Avoiding any setback during this important time can only result in healthier youngsters with better immune response throughout their lives.

I will try to write a part II to this article (Sweakers, Pigeon Milk, and Leaky Intestinal Linings) which will better explain the passing of immunity to the youngsters and what actually happens to the intestinal mucosal barrier that makes it at first "leaky" and then later allows it to "harden".

This whole development process is interesting and "not messing with this process", that is NOT using medications and anti-biotics, can only bring about better developed youngsters, better health in your loft and hopefully race birds that have developed innate protection against bacterias, viruses and other pathogens.