Effect of seasons on the microbiological and biochemical composition of poultry farm excreta

Impact of seasons on poultry farm excreta was assessed using 36 week old layer chickens that are fed with the same kind of feed. Fresh droppings and three months accumulated excreta were analysed at the peak of rainy, winter, summer and windy seasons. In both fresh and accumulated samples, changes in chemical composition in terms of pH, moisture, organic carbon, various forms of nitrogen, metal elements and level of macromolecules such as carbohydrates, proteins, lipids and free amino acids showed fluctuations with respect to seasons. Microbial activity was found high in accumulated samples in all the seasons. The biochemical and microbiological modulations in the fresh droppings could be attributed to the seasonal variations in the metabolic status of birds. The excretion of organic carbon, phosphorus, potassium, calcium, magnesium, sodium, manganese, carbohydrates and lipids were high in the rain seasons and hence chances for causing pollution are high. It was suggested to change feed composition seasonally in order to reduce the nutrient loss. Impact of seasonal fluctuation in the population of beneficial microbes (ammonia and nitrite oxidizers) as well as undesired microbes (urease and uricase producers) on the nutrient status in the excreta is highlighted.