Effect of Aeromonas hydrophila infection with high and normal water temperature on total hemocyte count, total plasma protein and histopathological differences in freshwater crayfish Astacus leptodactylus

In&nbsp; this&nbsp; study,&nbsp; the&nbsp; effect&nbsp; of&nbsp; water&nbsp; temperature&nbsp; on&nbsp; pathogenesis&nbsp; of&nbsp; Aeromonas&nbsp; hydrophila&nbsp; in&nbsp; freshwater&nbsp; Crayfish&nbsp; Astacus&nbsp; leptodactylus&nbsp; were&nbsp; investigated.&nbsp; In&nbsp; our&nbsp; study,&nbsp; The&nbsp; treatments&nbsp; Crayfish&nbsp; have&nbsp; exposed&nbsp; to&nbsp; A&nbsp; hydrophila&nbsp; with&nbsp; concentration&nbsp; of&nbsp; 3&times;106 CFUml-1&nbsp; in&nbsp; high&nbsp; water&nbsp; temperature (25˚C)&nbsp; and&nbsp; normal&nbsp; water&nbsp; temperature(10-15ċ).&nbsp; The&nbsp; untreated&nbsp; control&nbsp; groups&nbsp; in&nbsp; high&nbsp; water&nbsp; temperature (25˚C)&nbsp; and&nbsp; normal&nbsp; water&nbsp; temperature (10-15 ˚C)&nbsp; were&nbsp; disinfected&nbsp; by&nbsp; oxytetracyclin&nbsp; at&nbsp; concentration&nbsp; of&nbsp; 100 ppm&nbsp; for&nbsp; 24&nbsp; hours.&nbsp; The&nbsp; haemolymph&nbsp; samples&nbsp; were&nbsp; withdrawn&nbsp; for&nbsp; measuring&nbsp; of&nbsp; THC&nbsp; and&nbsp; TPP.&nbsp; For&nbsp; histopathological&nbsp; studie,&nbsp; the&nbsp; Crayfish&nbsp; samples&nbsp; were&nbsp; fixed&nbsp; in&nbsp; Davidson&nbsp; fixative.&nbsp; The&nbsp; results&nbsp; showed&nbsp; that&nbsp; the&nbsp; value&nbsp; of&nbsp; THC&nbsp; in&nbsp; control&nbsp; group1&nbsp; in&nbsp; comparing&nbsp; with&nbsp; control&nbsp; group2&nbsp; and&nbsp; two&nbsp; other&nbsp; treatments&nbsp;&nbsp;&nbsp; at&nbsp; 48h&nbsp; after&nbsp; experiment&nbsp; time&nbsp; were&nbsp; significant&nbsp; (p<0.05).&nbsp; Also&nbsp; the&nbsp; difference&nbsp; of&nbsp; THC&nbsp; value&nbsp; between&nbsp; control&nbsp; group 2&nbsp; with&nbsp; treatment&nbsp; group2&nbsp; at&nbsp; 144h&nbsp; after&nbsp; experiment&nbsp; time&nbsp; was&nbsp; significant&nbsp; (p<0.05).&nbsp; The&nbsp; finding&nbsp; of&nbsp; TPP&nbsp; value&nbsp; showed&nbsp; that&nbsp; there&nbsp; was&nbsp; significant&nbsp; difference&nbsp; between&nbsp; control&nbsp; group1&nbsp; and&nbsp; treatment4&nbsp; in&nbsp; last&nbsp; time&nbsp; after&nbsp; experiment&nbsp; time&nbsp; (336h)&nbsp; (p<0.05).&nbsp; In&nbsp; infected&nbsp; Crayfish&nbsp; to&nbsp; bacteria&nbsp; with&nbsp; high&nbsp; temperature,&nbsp; red&nbsp; and&nbsp; black&nbsp; spots&nbsp; and&nbsp; also&nbsp; wound&nbsp; were&nbsp; observed.&nbsp; The&nbsp; result&nbsp; of&nbsp; histopathology&nbsp; in&nbsp; heptopancreas,&nbsp; gill,&nbsp; heart&nbsp; and&nbsp; digestive&nbsp; tract&nbsp;&nbsp;&nbsp; showed&nbsp; hemocyte&nbsp; aggregation,&nbsp; necrotized&nbsp; tissue,&nbsp; dead&nbsp; cells&nbsp; within&nbsp; pyknosis&nbsp; and&nbsp; karyorrehexis&nbsp; of&nbsp; nucleus&nbsp; and&nbsp; vaculation&nbsp; of&nbsp; hepatopancreas.&nbsp; In&nbsp; treatment&nbsp; group1&nbsp; and&nbsp; control&nbsp; group1&nbsp; no&nbsp; pathological&nbsp; changes&nbsp; of&nbsp; heart&nbsp; were&nbsp; observed.&nbsp; In&nbsp; digestive&nbsp; tract&nbsp; no&nbsp; changes&nbsp; were&nbsp; appeared&nbsp; in&nbsp; treatment1&nbsp; and&nbsp; two&nbsp; others&nbsp; control&nbsp; group,&nbsp; but&nbsp; aggregation&nbsp; of&nbsp; hemocyte&nbsp; with&nbsp; pyknosis&nbsp; of&nbsp; nuclei&nbsp; was&nbsp; revealed&nbsp; in&nbsp; concentration&nbsp; of&nbsp;&nbsp;&nbsp; 3&times;106&nbsp; CFUml-1&nbsp; with&nbsp; high&nbsp; temperature.