Overview: prevalence and structure of metabolic diseases of laying chickens, their influence on egg quality and condition of young chickens

Abstract

The article analyzes and presents statistics on the number of laying hens in Ukraine, production, consumption and import of eggs for the last 5 years, the spread of metabolic diseases of laying hens on the basis of a review of literature sources. Metabolic disorders are the largest group of poultry diseases classified as metabolic diseases and cause significant economic losses. Hepatitis, hepatodystrophy, cirrhosis, liver abscesses, cholecystitis, and gallstone disease are diagnosed in laying hens as a result of impaired carbohydrate, lipid, protein, and mineral metabolism. With a lack or imbalance of calcium and phosphorus or D-hypovitaminosis, in chickens develop diseases such as osteoporosis and hypocalcemia, which reduce egg-laying, quality of hatching eggs and young poultry, and can lead to the death of embryos and adults. Hypovitaminosis (A, D, E) and microelementosis (Co, Cu, Zn, J) in poultry cause decreased immunity, disorders of hormonal system, growth, reproductive functions, egg production, dysfunction of internal organs and nervous system, contribute to the formation of defective eggs, development in embryo of alimentary diseases, which affects the hatchability and quality of young poultry. In view of this, the norms of feeding and keeping poultry are constantly being improved based on an in-depth study of these processes. The subject of this work was a comparative review of the results obtained by various authors on the most common metabolic diseases of laying hens, their impact on productive traits (laying), quality characteristics of eggs, embryogenesis, quality of young laying hens of modern high-yielding crosses. This review of literature sources can serve as a tool for determining the future direction of research, as well as an indicator of its practical application.