Biochemical parameters of laying hens and japanese quails (Coturnix coturnix japonica)

The evaluation of blood biochemical parameters is an important tool for monitoring the physiological, nutritional, and health status of commercial birds. However, species-specific reference values for laying hens and Japanese quails are still scarce or variable in the literature. The aim of this study was to establish reference values for serum biochemical parameters in these two species. Laying hens (Gallus gallus domesticus) and Japanese quails (Coturnix coturnix japonica) were kept under standardized rearing conditions and fed a balanced diet according to their nutritional requirements. Blood samples were collected by jugular vein puncture, centrifuged to obtain serum, and analyzed using an automated biochemical analyzer. The following parameters were determined: glucose, triglycerides, cholesterol, uric acid, urea, creatinine, aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase (GGT), alkaline phosphatase, total proteins, albumin, calcium, and phosphorus. For each variable, measures of central tendency, dispersion, and range were calculated. The results revealed differences between species, with quails showing higher mean levels of glucose and cholesterol, while hens presented higher serum calcium values. It can be concluded that the values established in this study provide a reference basis for clinical, diagnostic, and zootechnical applications, as well as supporting future research in physiology and nutrition of laying birds.