Indicators of gut health: feet!
Foot pad lesions are triggered by wet litter, which may be a result of poor intestinal health in poultry. In order to keep litter dry and birds healthy, it takes a fine balance of adding, retaining and removing moisture.
Starting with the feet
Foot pad lesions are regularly discussed as a welfare concern; they are, however, much more than that. When poultry show foot pad lesions they are at the end of a chain of events. With dry litter, independent of species or age, foot pads stay healthy. Foot pad lesions occur when litter stays moist over time. Therefore, they are largely determined by the dry matter (DM) content of the litter, not by something related to the feet.
The cause of unexpected wet litter is often poor intestinal health. Poor intestinal health may be linked to a variety of pathogens such as Clostridium perfringens and the Eimeria species. Both species benefit from low DM content in litter and can cause poor intestinal health.
Water addition – Water retention – Water removal from litter
Water in. The first-day litter will have a DM content of over 90 percent. The moisture content goes up per the age of the birds.
It is easy to estimate how much water should be added. Using a broiler as an example, assuming a final bird weight of 2.3 kilograms and with a 1.62 FCR, each bird will eat around 3.72 kilograms of feed in its life. Typical water consumption of a healthy bird can be 1.65 of feed, which is more than six litres of water per bird. From this, about 1.5 litres will leave the house through bird consumption and the rest will add moisture to the house, mainly the litter.
Water retention. The purpose of the litter is to temporarily retain moisture to make the surface dry, reduce ammonia emission and act as a source for the chicken to express natural behaviours such as scratching and dust bathing. A good litter will both absorb and release moisture readily.
Water removal. Water can only leave the litter and house through evaporation. Ventilation is not only a way to maintain respiratory health, but a crucial way to maintain high DM content in the litter. The key to maintaining a nice dry litter is to effectively remove water.
Avoiding wet litter is straightforward but depends on many factors
Wet litter and resulting foot pad lesions can occur when the water added exceeds water removed through the air. From the many factors influencing DM content of litter, several can be controlled such as diet, stocking density, housing and ventilation. Other factors such as climate are of course not able to be controlled. Controlling as many factors as much as possible will contribute to dry litter. What makes litter moisture vary the most is intestinal health. Birds that suffer from poor intestinal health will lose more water in faeces and drink more. An increase of water intake is the first indicator of illness for many diseases.
What is the solution for consistently dry litter?
The first solution is to manage ventilation, regularly check the diets and choose the best litter available locally. This will result in litters with acceptable DM content of 80 percent or more. To ensure that almost all cycles have good feet, intestinal health must also be well managed.
Proven tools for managing intestinal health are slow release butyrates such as ButiPEARL™ to ensure the integrity of the intestinal wall. CLOSTAT® has been proven to reduce litter moisture content by on average 10 percent. This can be explained clearly as it has been proven both to increase beneficial parts of the microbiome and modulate populations of potential pathogens such as Clostridium perfringens. If it is unclear which organism is causing intestinal problems, it can be beneficial to support the innate immune system with 1,4 beta glucans such as Aleta™ to prevent wet litter becoming a problem.