Changes in blood and urine parameters of carp exposed to diluted (20%) raw sewage for a short period were investigated. Carp exposed to the sewage lost their balance within 30 minutes. When carp lost their balance, haematocrite(Ht)and plasma non-nitrogenous compounds(NPN), ammonia. Ca2+,Mg2+, Sand catecholamines (CAs) increased significantly, whereas no remarkable changes were observed in urine parameters. Four hours after the exposure, marked changes were found in blood and urine parameters as follows; much higher values for Ht, plasma NPN, ammonia, glucose, lactate. Mg2+, S, Cl, Br and CAs, and for urine ammonia, S, Cl, K, Ca, Zn and Br were observed. After 12 hours, some slight aftereffects were still found on blood and urine parameters. After 36 hours, both blood and urine parameters recovered to the control levels. Effects of the sewage exposure on microflora in the gastrointestinal tract of carp were also studied. Microflora were widely different between upper and lower parts of the gastrointestinal tract in the control. Remarkable bacteriological changes in the tract, particularly in the lower part, were found 12 hours after the exposure. This study suggests that (i) even a short-term exposure to sewage causes considerable stress responses on carp, (ii) urinalysis and examination of gut microbes as well as blood test are effective for the diagnosis of physiological dysfunction in carp, and (iii) microflora in the gastrointestinal tract of carp are strikingly affected by the physiological conditions of fish and by microflora in environmental water.
l-Ornithine attenuates corticotropin-releasing factor-induced stress responses acting at GABAA receptors in neonatal chicks
