ABSTRACT
Red blood cells (RBC) morphologic evaluation through microscopy optical (OM) and SEM, provides information to forecast, evaluate, and monitor the functioning of many organs. Factors, such aging and diseases affect RBC morphology in both, human and animals. SEM is useful to evaluate RBC morphology, although its use in diagnosis and evaluation in dogs is limited, due to the availability and cost. The aim of this research was to assess the normal RBC morphology in adult, senior and geriatrician dogs, clinically healthy by OM and SEM. In addition to evaluating the age effect, sex, body size, and their interaction on erythrocyte morphometry. To carry out the research 152 blood samples were evaluated from dogs of different sexes and body sizes (small, medium, and large). Three groups were made based on dogs age: group I adults (1-7.9 years old), group II senior (8-11.9 years old), and group III geriatricians (>12 years old). Erythrocyte parameters were evaluated by OM (diameter, height, and axial ratio). Per each dog, the parameters of 20 erythrocytes were measured. A total of 2,600 cells were scanned with the AmScope™ Software scale. In addition, the RBC morphology was evaluated by SEM. Statistical analyses used analysis of variance and a general linear model, which allows the comparison of multiple factors at two or more levels (p < 0.05). The results of this study showed that diameter and height were lower in adult dogs than in senior and geriatrician dogs (p < 0.05). Whereas, sex, body size, and the interaction did not show a significant effect (p > 0.05). Additionally, some images of anisocytosis, polychromasia, and poikilocytosis (echinocytes, acanthocytes, codocytes, spherocytes, stomatocytes, dacryocytes quatrefoil, and elliptocytes) were obtained by OM and SEM. Our study provides information about the morphological and morphometry alterations of adult, senior, and geriatrician dogs RBC. This work contributes to future investigations and the diagnosing diseases, where it is necessary to evaluate the morphology of RBC.
ABSTRACT
BACKGROUND: Blood biochemistry and reference intervals help to differentiate between healthy and ill dogs as well as to provide information for the prognosis, evaluation, and monitoring; however, these intervals are often obtained from adult animals. It is essential to understand that puppies and adults are physiologically different, which justifies the need to obtain age-specific biochemical reference intervals. The aim of this research was to assess the potential effect of age, sex, body size, and their interaction on routine biochemical analytes and physiological constants (body temperature, heart rate, and respiratory rate). To carry out the research, we selected 197 healthy dogs of both sexes and different body sizes (small, medium and large) classified by age: group I (4-8 wk), group II (9-24 wk), group III (25-52 wk), and group IV (> 52 wk). The biochemical analysis included the measurement of the enzymatic activity of aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP), and the concentrations of cholesterol, triglycerides, total proteins, albumin, globulins, glucose, urea, and creatinine. Statistical analyses used analysis of variance (ANOVA) and a general linear model (GLM), which allows the comparison of multiple factors at two or more levels (p < 0.05). RESULTS: The results of this study showed that ALT, total protein, albumin, globulin, urea, creatinine, and body temperature levels were lower in puppies than in adult dogs of group IV (p < 0.05), while the enzymatic activity of ALP, LDH, glucose concentration, and heart rate were higher. Whereas sex, body size and the interaction did not show a significant effect (p > 0.05). CONCLUSIONS: Some biochemical components are influenced by age. For this reason, this manuscript contributes with additional data for the clinical interpretation of blood biochemical results in puppies.
