Hematologic and Serum Biochemical Characteristics of Belgian Blue Cattle

Simple Summary: Since they have a unique phenotype, with an approximately 20% increase in muscle mass, we hypothesized that Belgian blue (BB) cows may have hematologic and biochemical characteristics that are significantly different from those of other cattle breeds. However, most available reference intervals in cattle are derived from dairy cows, mainly Holstein Friesian (HF) cows. Therefore, the aim of our study was to measure and compare biochemical and hematologic parameters in clinically healthy BB and HF cows. We studied 183 clinically healthy adult BB and HF cows. Our results confirmed that BB and HF represent different populations from a laboratory perspective. Therefore, we propose the first breed-specific reference intervals for BB, which are essential to improve the health management of this breed. Belgian blue (BB) cattle have an 11-bp deletion in myostatin that causes skeletal muscle hyperplasia and increased muscle mass, leading to a 'double-muscled' phenotype. Preliminary data suggest that this phenotype may be associated with breed-specific hematologic and biochemical values. Therefore, in this study, we sought to compare hematologic and serum biochemical parameters in healthy BB and Holstein Friesian (HF) cows and to propose breed-specific reference intervals for BB cows. Hematologic parameters, total protein, creatinine, creatine kinase (CK) and aspartate transaminase (AST) activities, albumin, and globulins were measured in 183 clinically healthy adult BB and HF cows. There were significant differences between BB and HF cows in 17 of 27 measured parameters. BB cows had significantly higher creatinine concentration and CK and AST activities (p < 0.001). RBCs, hemoglobin, hematocrit (p < 0.001), MCV and lymphocytes (p < 0.05) were also significantly higher in BB cows compared with HF cows. The average N/L ratio was greater than 1 in both breeds. These results suggest that BB and HF cows have significantly different clinically relevant hematologic and serum biochemical values, and, therefore, breed-specific reference intervals should be used.