PHYSIOLOGICAL-CHANGES WITH AGE IN THE DOG (LONGITUDINAL-STUDY IN A BEAGLE DOG COLONY)

In order to determine age-dependent changes and to be able to distingu ish between physiologic and pathologic changes with age in the dog, we investigated 15 Beagles aged 4 to 9 years over a period of 5 years in a combined cross-sectional and longitudinal study 4 times a year and determined the changes in the clinically relevant parameters. We were able to demonstrate that most of the examined parameters change with a ge: in red blood cells: erythrocyte count, hemoglobin concentration, p acked cell volume, MCV, MCHC and reticulocyte count; in white blood ce lls: total white blood cell count, the number of circulating lymphocyt es and neutrophils; in plasma enzymes: butyrylcholinesterase, gamma GT , LDH and GLDH; in plasma nutrients and metabolites: triglycerides, ch olesterol, creatinine and albumin; in plasma electrolytes and metals: calcium, iron, phosphate and zinc; in functional parameters: heart rat e and TP-segment in the ECG during treadmill running, and body tempera ture, oxygen saturation, oxygen concentration, blood glucose level, he matocrit, hemoglobin concentration and red blood cell count in the rec overy period after running; in the immune system: lymphocyte prolifera tion and blood sedimentation rate; in metabolism: turnover rate of glu cose and triiodothyronine plasma concentration. The results of our inv estigation show that it would be important to distinguish between path ological and physiological changes with age and that such changes shou ld be taken in account during diagnosis, therapy and prophylaxis for t he old animal. The observed age-associated changes may form the basis for the multimorbidity of old age but are not in themselves to be rega rded as pathological processes.