Establishing biochemical reference intervals in dogs using the Respons920® analyser: effects of age and sex

Abstract

Dogs are among the world’s most cherished companion animals, reflecting their increasingly close relationship with humans. As pets become integral members of households, the demand for accurate and reliable veterinary diagnostic tools is growing, particularly to ensure optimal health and clinical care. This study aimed at establishing species-specific reference intervals for canine serum biochemical parameters using the Respons^®920 (DiaSys) liquid biochemistry analyser, with applicability in routine clinical practice. Additionally, the influence of sex and age on these parameters was assessed. A total of 193 clinically healthy dogs were included. Reference intervals were established for commonly used serum biochemical parameters: total proteins (TP), albumin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), phosphorus, calcium, creatinine, urea, cholesterol, triglycerides, sodium, potassium, and chloride. Reference intervals were calculated using the Reference Value Advisor software, strictly following the American Society of Veterinary Clinical Pathology guidelines. Statistical analysis revealed significant sex-related differences for ALT, AST, and urea, with higher values observed in males. Age-related differences were also identified for ALP, phosphorus, and TP, particularly between younger and older age groups. Although these differences were not sufficient to justify separate reference interval partitioning, they should be considered by clinicians during interpretation. This study provides species- and instrument-specific reference intervals for canine serum biochemistry using the Respons^®920 analyser, and contributes valuable data on the influence of sex and age on routine biochemical parameters in dogs.