How are birds defending against pathogens?

Poultry as well as other animals must have a way of protecting their body from external factors that can create problems. These defenses are going to fight against various antigens (microorganisms and their metabolites) to decrease the possibility of the animal getting sick; this protection mechanism it’s called immune system.

The main role of the immune system is to identify and control organisms and/or substances that are considered foreign, that managed to enter the body. A variety of mechanisms that have to work together and precise are employed to achieve an effective response, and secure the animals well-being.

In birds as well as in other animals, the immune system is formed by two different parts that work together to avoid the damage that foreign agents can cause to the body; the innate and the adaptive immunity.

Innate immunity

This is the first line of defense against a wide variety of pathogens. This part of the immune system responds with a non-specific reaction, meaning it won’t be distinguishing between different pathogens. The innate immunity is composed by anatomical and physiological barriers, as well as, cellular, DNA and protein components; which will provide help to initiate the defense response:

·       Anatomical and physiological barriers: many pathogens cannot breach intact skin and mucosa membranes. High body temperature of birds is another barrier (physiological) that can prevent microorganism survival or replication once the antigen is in the body.

·       Genetic selection: due to genetic selection, poultry now a days could lack of receptors required by pathogens to be able to infect; making some lines of poultry more resistant to specific diseases then others.

·       Established beneficial microflora: many organs maintain a dense, stable microbial population, which will help to avoid colonization of unwanted microorganisms (principle of competitive exclusion). 

·       Immune system cells: Cells which will attack antigens when activated by the foreign bodies. The most important ones are White blood cells, Mast cells, Phagocytes and Natural killer cells. 

All these mechanisms will help the body to attack pathogens. But as described previously, it won’t be a specific response against foreign bodys; but a general one. If the innate immunity cannot control the problem, with the previously described strategies, the second type of immunity will start to respond.

Adaptive immunity

The adaptive or acquired immunity uses other approach to control pathogens. It targets and recognizes specific features from the surface of the foreign body before starting a cascade of steps leading to the elimination or control of the pathogen. By having a more specific mode of action, it will also create a memory that will provide protection for future encounters with the pathogen. These antigen specific response is created by antibodies or immune cells. There are 2 different types of adaptive immunity; the humoral and the cellular-mediated one. 

The humoral response is the first line of defense from the adaptive immunity to eliminate pathogens and their metabolites that are foreign to the body. This response uses blood as the vehicle to transport and mobilize immunoglobulins (IgM, IgY, and IgA) which were produced by the B-lymphocytes. The main action of this immunoglobulins is to identify and neutralize foreign bodies. 

The adaptive cell mediated immunity on the other side involves the T-lymphocytes instead of the B-lymphocytes, and are the ones that will fight against the pathogens that were not neutralized or eliminated by the circulating immunoglobulins from the humoral response. The -lymphocytes, which are programmed in the thymus, will have various modes of action that can vary from producing lymphokines, directly destroy disease organisms, to function as a support for B-lymphocytes or macrophages to work properly. 

All of this mechanisms that form part of the immune system, will help the avian body to avoid the progression of a pathogen colonization and reduce the possibility of an infection. Even though it is conformed by a complex and multilayered system, many factors can impact the response capacity of this system. To reduce the possibility of a non-properly working immune system, there are nutritional inclusions that can be made to enhance and support the immune system, in the form of feed and water additives. 

By including ingredients that are known to have immune booster effects, we can help the animal on it’s fight against all possible infections.

In XVET we count with many products that can support the immune system, utilizing different ingredients and approaches that have been proven to have a strong effect on the boosting this system. Some of the most important products which are directly helping immune system are: 

·      Turbo Tox and Dyna-MOS: Smart formula rich in high quality ß-Glucans and MOS 

·      Zincotin: Highly bioavailable organic Zinc

For further information, please contact technical@xvetgermany.com