Breed-specific hematologic reference intervals in healthy adult Dogues de Bordeaux

Hematological and Biochemical Reference Intervals for 5 Adult Hunting Dog Breeds Using a Blood Donor Database

Simple Summary

Hematological and biochemical profiles are essential in the diagnosis and monitoring of disease in veterinary medicine, requiring optimal Reference Intervals (RIs) for accurate interpretation. The aim of this study is to determine hematobiochemical RIs for 5 hunting dog breeds from a blood donor database and to compare them with laboratory established and published RIs to identify possible breed and attitude-related differences. A total of 445 healthy adult hunting dogs (156 Ariégeois, A; 52 Bleu de Gascogne, B; 64 Bracco italiano, C; 123 Segugio italiano, D; 50 Briquet Griffon Vandeen, E) were included in the study. Significant differences in 12 hematologic and serum biochemical analytes, for which a breed-specific variation appears to be the most plausible explanation, were detected, and new RIs for these parameters are provided.

Abstract

Numerous studies have shown the importance of breed-related differences between hematological and biochemical results in veterinary medicine. The aim of this study is to determine hematologic and biochemical Reference Intervals (RIs) for 5 hunting dog breeds from a blood donor database, adopting an indirect sampling method, and to compare them with laboratory established and published RIs to identify possible breed and attitude-related differences. The study analyzed the blood parameters of 445 adults (222 females and 223 male, with age ranging from 2 to 8 years, mean age 5.3 years), client-owned, clinically healthy blood donor dogs of 5 breeds: 156 Ariégeois, 52 Bleu de Gascogne, 64 Bracco italiano, 123 Segugio italiano, and 50 Briquet Griffon Vandeen. Statistical analysis was performed as recommended by the American Society of Veterinary Clinical Pathology (ASVCP) guidelines. RIs for red blood cells (RBC), hematocrit (HCT), hemoglobin (HB), main corpuscular volume (MCV), main corpuscular hemoglobin (MCH), main corpuscular hemoglobin concentration (MCHC), red distribution widht (RDW), white blood cells (WBC), and differential leukocytes count, PLT, Albumin, Total Protein, Urea, Creatinine, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) for each of the 5 breeds were performed, and significant differences with the established RIs were detected. We found significant differences in 12 hematologic and serum biochemical analytes for which a breed-specific variation appears to be the most plausible explanation. New RIs for HCT, MCH, MCHC, RDW, PLT, Monocytes, Eosinophils, Albumin, Urea, Creatinine, AST, and ALT are provided for at least 1 breed. Breed-specific RIs for adult hunting dogs will help avoid misinterpretation of laboratory results in these breeds.

Age-associated and breed-associated variations in haematological and biochemical variables in young labrador retriever and miniature schnauzer dogs

Breed, sex and age effects on haematological and biochemical variables were investigated in 24 labrador retriever and 25 miniature schnauzer dogs during the first year of life. Blood samples were taken regularly between weeks 8 and 52. White blood cell and red blood cell counts, haemoglobin concentration, haematocrit, mean cell volume, mean cell haemoglobin, mean cell haemoglobin concentration, platelet count as well as total protein, albumin, calcium, phosphate, alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, glutamate dehydrogenase, total cholesterol, triglycerides, creatine and urea were evaluated. For all haematological and biochemical parameters, there were significant effects of age on test results. Statistically significant effects for breed and the breed×age interaction on test results were observed for most of the parameters with the exception of haemoglobin. Variations in test results illustrate growth related alterations in body tissue and metabolism leading to dynamic and marked changes in haematological and biochemical parameters, which have to be considered for the interpretation of clinical data obtained from dogs in the first year of life.

Genetic Mapping of Novel Loci Affecting Canine Blood Phenotypes

Since the publication of the dog genome and the construction of high-quality genome-wide SNP arrays, thousands of dogs have been genotyped for disease studies. For many of these dogs, additional clinical phenotypes are available, such as hematological and clinical chemistry results collected during routine veterinary care. Little is known about the genetic basis of variation in blood phenotypes, but this variation may play an important role in the etiology and progression of many diseases. From a cohort of dogs that had been previously genotyped on a semi-custom Illumina CanineHD array for various genome-wide association studies (GWAS) at Cornell University Hospital for Animals, we chose 353 clinically healthy, adult dogs for our analysis of clinical pathologic test results (14 hematological tests and 25 clinical chemistry tests). After correcting for age, body weight and sex, genetic associations were identified for amylase, segmented neutrophils, urea nitrogen, glucose, and mean corpuscular hemoglobin. Additionally, a strong genetic association (P = 8.1×10⁻¹³) was evident between a region of canine chromosome 13 (CFA13) and alanine aminotransferase (ALT), explaining 23% of the variation in ALT levels. This region of CFA13 encompasses the GPT gene that encodes the transferase. Dogs homozygous for the derived allele exhibit lower ALT activity, making increased ALT activity a less useful marker of hepatic injury in these individuals. Overall, these associations provide a roadmap for identifying causal variants that could improve interpretation of clinical blood tests and understanding of genetic risk factors associated with diseases such as canine diabetes and anemia, and demonstrate the utility of holistic phenotyping of dogs genotyped for disease mapping studies.

Characterization of Proteinuria in Dogue de Bordeaux Dogs, a Breed Predisposed to a Familial Glomerulonephropathy: A Retrospective Study

Dogue de Bordeaux dog has been reported to be predisposed to a familial glomerulonephropathy that displays some morphological modifications reported in focal and segmental glomerulosclerosis. Prevalence of quantitatively abnormal renal proteinuria was recently reported to be 33% in this breed. The nature of the proteinuria was assessed by sodium dodecyl sulfate-agarose gel electrophoresis and determinations of urinary markers (urinary retinol-binding protein, urinary N-acetyl-β-glucosaminidase, urinary albumin and urinary immunoglobulin G) on stored specimens. Diagnostic performances of sodium dodecyl sulfate-agarose gel electrophoresis to identify dogs with elevated urinary biomarkers were assessed. Samples from 102 adult Dogue de Bordeaux dogs (47 non-proteinuric [urine protein-to-creatinine ratio ≤ 0.2], 20 borderline-proteinuric [0.2< urine protein-to-creatinine ratio ≤ 0.5] and 35 proteinuric dogs [urine protein-to-creatinine ratio >0.5]) were used, of which 2 were suffering from familial glomerulonephropathy. The electrophoretic protein patterns, for all but one proteinuric dog, were indicative of a glomerular origin and, in all dogs, the urinary albumin concentration related to creatinine concentration and the urinary immunoglobulin G concentration related to creatinine concentration were above the upper limit of the reference interval established for the breed. Sensitivity and specificity of sodium dodecyl sulfate-agarose gel electrophoresis identifying dogs with elevated urinary albumin concentration were 94% and 92%, respectively, while diagnostic performance of sodium dodecyl sulfate-agarose gel electrophoresis in detecting dogs with elevated urinary immunoglobulin G concentration yielded sensitivity and specificity of 90% and 74%, respectively. These results suggest that all proteinuric and some borderline-proteinuric Dogue de Bordeaux dogs likely have underlying glomerular lesions and that sodium dodecyl sulfate-agarose gel electrophoresis and urinary markers might be useful to screen dogs with borderline-proteinuria. Additional investigations are warranted to assess if these findings are related to the familial glomerulonephropathy.