Heat stress impairs egg production in commercial laying hens infected by fowl typhoid.

Heat stress impairs egg production in commercial laying hens infected by fowl typhoid. Avian Pathol. 2020 Nov 04;:1-18 Authors: Rubio MDS, Rodrigues Alves LB, Viana GB, Benevides VP, Lima TS, Santiago Ferreira T, Almeida AM, Barrow PA, Berchieri Junior A Abstract Salmonella Gallinarum (SG) is a avian-restricted pathogen that causes fowl typhoid in poultry. Although it has been reported frequently over many decades in poultry flocks worldwide, the microorganism is more commonly associated with poultry in developing countries, particularly those with high ambient temperatures, where the acute form of the disease results in considerable economic losses. A more detailed investigation of environmental factors that affect the course of disease may assist in identifying effective prevention and control measures. Heat stress is known to impair the immunological response to a variety of pathogens and clearly may be an important contributory factor in the prevalence of disease in countries with warm or hot climates. Thus, the objective of the present study was to evaluate the effects of heat stress on chickens infected with SG. For this, light and semi-heavy commercial laying hens were distributed randomly within four groups as follows: infected and non-infected groups in rooms held at ambient temperature and infected and non-infected groups under heat stress. Clinical signs, egg production, and mortality were recorded daily. Bacteriological c...
Source: Avian Pathology - Category: Pathology Authors: Tags: Avian Pathol Source Type: research