Irritant effect and efficiency of inclusion of spirulina biomass enriched with sulphur in the young dogs’ diets

The content of nutrients and biologically active substances in the biomass of Spirulina platensis allows it to be used effectively in animal diets. By adjusting the mineral composition of the nutrient medium for Spirulina platensis, it is possible to change the content of macronutrients in the cells of the blue-green algae. One of these mineral elements is sulphur. This element is an essential component of several amino acids, enzymes, vitamins and coenzymes. By introducing additional doses of Sulphur (purified, nutritional form and glauber’s salt) into the nutrient medium, Spirulina platensis biomass with a high content of the element under study was obtained. To further use spirulina biomass with a high content of Sulphur as a feed additive in the feeding of farm animals and poultry, it is advisable to study the harmful effects of blue-green algae biomass and to establish the effectiveness of its inclusion into animal diets. The study aimed to determine the irritating effect of Spirulina platensis biomass with a high sulphur content on the mucous membranes of the eyes and to establish the effectiveness of its inclusion in the diet of young dogs. The irritant effect has been studied by applying a suspension of Spirulina to the conjunctival sac of the left eye of rabbits aged 2.5 months and weighing 2.32-2.33 kg. The experimental animals have been observed for 14 days. At the end of the study, the serum of rabbits was examined for protein metabolism. To study the effectiveness of using spirulina biomass as a feed additive, puppies from the control group were fed a feed mixture without adding algae. Dogs from the I-III experimental groups were fed a feed mixture containing Spirulina platensis biomass with a high content of sulphur in the amount of 0.5, 1.0 and 1.5 % by weight. The study of the irritating effect of spirulina biomass proved its non-toxicity, which allows it to be used as a feed additive, including in the feeding of young dogs. No disturbances in protein metabolism in rabbits were found when a suspension of Spirulina platensis biomass was applied to the mucous membrane of their eyes. The addition of 1.0 and 1.5 % of Spirulina biomass to the feed mixture increased the body weight of puppies by a statistically significant amount. Keywords: experimental animals, the harmful effect of Spirulina platensis biomass, puppies’ body weight, feed mixture, hyperaemia, oedema.