Natural Immunity

Jan 20 , 2023

Andrew Vlcek

Natural Immunity

As with many facets of our farm, we let nature be our teacher. Raising chickens without antibiotics doesn’t require seclusion from pathogens, but rather getting the amount of exposure just right so that they have immunity but they don't succumb to parasitic overload. We want to provide a setting in which our birds can achieve natural immunity to pathogens such as coccidiosis. 

This starts in the brooder stage. The brooder is where our pasture raised chickens start their lives before they go to pasture. Before the chicks have their feathers, they are unable to regulate their body temperature, and so the brooder is a shelter with warm zones in which they can utilize to warm up or cool down. In the brooder, we have wood chips as bedding, and this is where we begin to let nature loose to achieve a natural immunity in our chickens.

Old litter has more of what’s called “oocysts.” This is a hardy, thick walled stage of the life cycle of coccidian parasites. Old litter has a higher amount of oocysts present and the birds get exposure early. This may sound like a bad thing, but keep in mind, that’s not the only microbial bug floating around in that bedding. When baby chicks come from a hatchery, they come in with bacterial flora on the chick box and paper liners so it’s already there. Even when hatched on a farm, there is no escaping this microbial world. So this diverse microflora – the good bacteria in the litter, helps to competitively exclude the bad. The exposure to the oocysts, along with many other microbials, help to stimulate healthy immune function without any one becoming a dominating force. Parasites are present, but are forced to compete to survive and all play a role.


Fresh litter has more environmental bacteria, while the reused litter has more intestinal bacteria. This means by leaving just a little bit of old litter behind when putting in new bedding will supply the birds with a more balanced environment of organisms at an earlier age, diversifying the landscape and helping develop immunity to the pathogenic bacteria through gentle exposure with no outbreaks.

This method of placing new wood chips on top of old is referred to as “Deep Bedding” and is common on regenerative farms and homesteads alike. Using this method has other benefits as well, but it plays a big part in strengthening our birds from an early age.

Diversity, not exclusion, is the key. By working in alignment with nature, our chickens are able to live healthy, happy lives without the use of pharmaceuticals. For our chickens, it’s “Bugs, Not Drugs!”