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

Abstract

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.

Effect of Age, Sex, and Breed on the Blood Biochemistry and Physiological Constants of Dogs From 4 Weeks to > 52 Weeks of Age.

“…The serum concentration of total proteins and albumin showed an evident effect on age. These results agree with previous research (4,5,9,14). Age-associated increase of total protein and albumin are attributed to normal immune stimulation, what results in an elevated globulin fraction and albumin production derived from improved liver function and intestinal absorption (1).…”

“…The enzymatic activity of AST from this research did not evince a signi cant effect, which agrees with the studies from other authors (5,13). Nonetheless, other research did nd age-related differences in AST enzyme activity (9,10). On the other hand, this study shows that the enzymatic activity of the ALT tends to increase with age.…”

“…Although ALT predominates in the liver, AST is also present in cardiac muscle, skeletal muscle, liver, and kidneys. The agedependent activities in both enzymes appear to correlate well with tissue growth (9).…”

“…The physiologic differences between puppies and adults dogs require an age-speci c biochemical RI, as in most species (5,7); thus, the RI for adults should not be used in puppies since they lead to inaccurate interpretation of the results (2,5,8). When interpreting clinical data obtained from dogs during their rst year of life, growth-related alterations and metabolism changes in biochemical limits should be considered (6,9).…”

“…Limited studies have examined the effect of age, sex, and breed on biochemistry variables in puppies, but most of these studies were performed in a controlled laboratory, environment, or with speci c breeds where dogs experienced identical living conditions and followed the same diet (4,(8)(9)(10). In most cases the puppies' history and physical examination are the same as for adults; however, there may be some variations in the physiological constants.…”