The aim of the study was to determine whether cortisol and secretory Immunoglobulin A (sIgA) could be used as an indicator of acute stress in both young and adult dogs. Seventeen German shepherd puppies were exposed to the Puppy test (challenge test) at the age of seven weeks. This test has been routinely used to assess the future working ability of potential police dogs. In addition, ten adult females were subjected to 4 minutes of defense training under stressful conditions. Saliva was collected from the puppies and adult females before testing and 20 minutes after the start of testing, using a cotton swab held for 1–2 minutes in each dog's mouth. Cortisol concentrations increased after the test compared to the control sample both in puppies and the adult females. However adult females showed a significant decrease in sIgA after defense training while puppies showed a tendency of increase in sIgA. We propose that salivary cortisol could be used as an indicator of stress in puppies during early ontogeny. It is not yet clear whether sIgA could be used as a useful indicator of short-term stress in dogs.

Milk composition of nine lactating German Shepherd nursing females was studied. The experiment took place at the breeding facility of Police of the Czech Republic (breeding centre for service dogs in Domažlice) in days 2−30 of the females’ lactation. Females were given a commercial granulated feeding mixture (starter category). Canine milk samples were analyzed using an infra-red instrument MilkoScan FT 120. Calculated mean values for colostrum (day 2 postpartum) and normal milk (days 4−29 postpartum) were: 23.86 and 24.63% for total solids, 8.14 and 7.22% for protein, 6.04 and 5.76% for casein, 10.22 and 11.32% for fat, 3.40 and 4.48% for lactose. German Shepherd milk showed almost no variation in composition after day 4 of lactation. Differences observed between colostrum and normal milk composition were statistically insignificant but not for lactose. No significant differences in density and other composition parameters between colostrum and normal milk were identified.