Urinalysis in Great Dane Puppies from Birth to 28 Days of Age

SIMPLE SUMMARY: Still, nowadays, small animal perinatology is quite an unknown field of veterinary medicine. To help decrease the high mortality rates reported for canine newborns, veterinary practitioners should become more aware of neonatal physiology and pathology, focusing their attention on metabolic balance. It is impossible to discriminate healthy puppies from pathological littermates in the absence of reference ranges for specific parameters, which are obviously different from those of adults. Since blood samples are more difficult and dangerous to collect from newborns, practitioners could rely on urinary samples, easily gathered by the stimulation of the somato-vesical spinal reflex. The present research, based on 624 urine samples, offers results that can be used as references for the first-line evaluation of newborn Great Danes by dipstick rapid urinalysis. In healthy puppies, specific gravity and pH vary from birth to 28 days of age, while glucosuria and proteinuria are never reported. The present results, derived from a sample of single-breed puppies, can represent the starting point for a further multi-breed evaluation. ABSTRACT: Urinalysis, a common test in infants, could represent a suitable non-invasive clinical tool in puppies. In dog neonates, urine is easily collected by stimulating the somato-vesccal reflex. Information on urine characteristics during the neonatal period is missing. Beside instrumental laboratory analyses, the dipstick was proven useful for rapid urinalysis to evaluate specific gravity (SG), pH, leukocytes, nitrites, glucose, proteins, ketones, urobilinogen, bilirubin, and blood. The present study aimed to describe urinalysis features by the dipstick test and refractometer along the neonatal period. Urine samples (n = 624) were collected by manual stimulation from 48 healthy Great Danes, daily from birth to seven days, then twice a week until 28 days, to assess age-related changes (ANOVA, p < 0.05) and the possible effects of gender and litter (T-test, p < 0.05). The SG and pH significantly changed during the neonatal period. Other parameters did not vary significantly in relation to age. No significant differences were observed either among litters or between genders. The present study confirmed that canine kidneys are able to concentrate urine from the second week of age when the urinary SG started to be similar to adults, while pH still increased towards the typical values of adults at 28 days. Significant glucosuria and proteinuria were never detected. Dipstick urinalysis represents a useful first-line complementary tool in newborns clinical examination, providing information about systemic homeostasis.