Changes in serum protein, serum compound protein, and ascitic protein were investigated in dogs infected with Dirofilaria immitis by using paper electrophoresis. Changes in serum protein which occurred in a great number of infected dogs consisted of a decrease in albumin and an increase in beta-and gamma-globulin. They usually included an increase in total protein concentration. In the severe case with an accumulation of ascitic fluid, there were a striking rise in gamma-globulin and a significant decrease in albumin. Also there was a tendency for the alpha- and beta-glycoprotein fractions and the beta-lipoprotein fraction to be elevated in many cases. These exhibited a markedly great increase in accordance with the progress of the disease. On the other hand, the protein patterns of the ascitic fluid resembled those of the serum, but the albumin composition of the former showed a higher percentage than that of the latter. In general, no notable changes were observed in the proteins in roundworm, tapeworm, and whipworm carriers which manifested no clinical symptoms of parasitism. Whereas albumin and alpha-2-, beta-, and gamma-globulin underwent remarkable changes in the severe case of hookworm disease, such changes were not distinctly evidenced in these carriers. On the other hand, remarkable changes were found in many heartworm carriers, which exhibited a protein response similar to that obtained in the chronic form of schistosomiasis. Therefore, it was presumed that the serum protein pictures in canine filariasis were characteristic not of the specific disease but of the host's reaction to the infection and injury.
1. When Hayem's solution containing 0-1.0% HgCl2 was used in microscopical examination the blood, clumps of erythrocytes appeared more of less in all kinds of animals. They were very large in number in the blood of goats, not so large in that of sheep and swine, and very small that of horses, cattle, and dogs. 2. It was thought that such clump had been caused in the diluted blood of horses and cattle mainly by some factors existing in the blood plasma and in that of sheep, goats, swine, and dogs by some factors in the erythrocytes. 3. There were the following relations between the concentration of HgC12 in Hayem's solution and the species of animals in which hemolysis occurred when such solution had been used as diluent: under 0.25% in cattle, under 0.05% horses and dogs, and under 0.01% in goats, sheep, and swine. 4. Taking the clumping of erythrocytes and hemolysis into consideration, the optimum concentrations of HgC12 in Hayem's solution are as fallows; 0.25-1.0% for horses and dogs, 0.5% for cattle, and 0.05% for sheep, goats, and swine. 5. No clumping occurred in physiologic saline solution at all, but hemolysis appeared in the blood diluted with this solution in all domestic animals examined in a short time. Therefore, physiologic saline solution cannot be a suitable diluent for erythrocytes of domestic animals. 6. When blood was diluted with Gowers' solution, no clumping nor hemolysis occurred for 24 hours. So, this solution can be recommended as a satisfactory diluent. 7. Toisson's solution caused no clumping but sometimes hemolysis especially in swine.