Litter is used to absorb moisture and excreta and provides thermal insulation and cushioning from the earth or concrete floor. Birds will grow on slippery and sticky surface if the litter reaches a high moisture content - to be defined as “wet litter”-; which will lead to many concerns in this condition.
The consequences of wet litter include footpad dermatitis, increased ammonia concentrations and bad odor. Wet litter also increases a risk to food safety and bird health including dysbacteriosis.
Several causes may contribute to wet litter such as environmental housing, health and nutritional factors. Implementing control measures can help prevent wet litter problems.
Management factors:
- All bedding materials should have good water holding capacity and reasonable drying rates. Litter friability, susceptibility to cake formation and water activity are also important properties as these contribute to the undesirable side-effects associated with wet litter.
- Water activity (Aw) is a thermodynamic property that relates to the relative availability or freedom of water in a material. Aw is generally accepted to be more closely related to microbial, chemical and physical properties of natural products, than total moisture content (and maybe a better measure of litter quality). The underlying mechanisms leading to the negative effects of wet litter is related to either pathogenic organisms (bacteria, fungi) or by direct contact with water. Aw directly contributes to these mechanisms.
- Design, management of and ventilation of the poultry house (temperature, humidity and airflow) are all-important for litter condition. Controlled laboratory studies have shown that exposure to in-a relative humidity of 75% was sufficient to cause wet litter. A thermostatically controlled ventilation system and adequate insulation allows control of temperature and relative humidity. Control of relative humidity reduces water absorption by the litter and also reduces drips from water that condenses on in-shed surfaces.
Nutritional factors:
- High intake of the mineral’s potassium, sodium, magnesium, sulfate or chloride can lead to excessive water consumption and hence water excretion. If a wet litter problem occurs, feed levels of sodium and chloride (salt) should be checked.
- The water should be checked periodically for mineral concentrations. Poor quality dietary fat or rancid fat can lead to wet fecal droppings.
- Feed ingredients such as wheat, barley, and rye will often result in wet droppings. To control wet droppings associated with some feed ingredients, it is usually necessary to use a suitable commercially available enzyme preparation in the diet.
- The moldy feed might contain huge amounts of mycotoxins which irritates the digestive tract and causes marked pathological changes leading to increased water consumption and wet droppings, hence, only quality feed should be fed to the animals.
Disease and health factors:
- Any disease that affects the normal digestive gut physiology will have a direct impact on the nutrient absorption and excretion, thus, it is a potential contributor to the wet litter.
- The secondary effect will happen when the birds stop eating but maintain water consumption, resulting in the higher moisture content of the droppings.
Fig. 1. The science of avian droppings. Examining droppings on a daily basis in the poultry house allows you to identify the first signs of wet litter and intestinal disorders.
Find hereby an overview of diseases affecting wet litter:
Coccidiosis
A disease of universal importance in poultry production caused by the protozoa Eimeria, causing intestinal damage resulting in gut inflammation and causes wet litter.
Necrotic Enteritis (NE)
This is the most common bacterial disease in modern broiler flocks. Early signs of a NE outbreak are often wet litter and diarrhea.
the two quite different disease entities are often interrelated in practice.
Dysbacteriosis
A non-specific bacterial enteritis will also result in wet litter. It has been proposed that dysbacteriosis is an imbalance in intestinal microflora resulting in malabsorption.
Viruses
Viruses associated with malabsorption can increase the moisture content of the bird’s droppings.
