Effects of Cold Stress and Ammonia Concentration on Productive Performance and Egg Quality Traits of Laying Hens

摘要

In the cold season, in order to alleviate the adverse effect of the low temperature, restricting or reducing ventilation is one of the common methods to preserve indoor heat to ensure the suitable temperature for hens in many poultry houses with no heating equipment. However, ventilation is the most important means to discharge ammonia in the house and ensure the indoor air quality in poultry farms. Measure of limiting ventilation to save energy usually causes the accumulation of gaseous ammonia released by poultry manure, which results in an increased indoor ammonia concentration. Therefore, studying the performance of laying hens exposed to a long-term ammonia concentration is of great significance for ventilation management in winter. In addition, it is not clear how the interaction between low temperature and ammonia concentration affects the performance of laying hens. Therefore, this study aims to evaluate the effects of temperature, ammonia and their interaction on productive performance and egg quality of laying hens breeding from the start to the peak period of laying. The study is of great significance to the poultry industry regarding the ventilation management in winter from the perspective of controlling temperature and ammonia concentration. It is also a reference for ensuring layer productive performance and egg quality.