Interspecies differences in mixed function oxicdase activity in birds: relationship between feeding habits, detoxication activities and organochlorine accumulation

• Published in: Environmental Pollution
• Main Authors: FOSSI, M. C., MASSI, A., LARI, L., MARSILI, L., FOCARDI, S., LEONZIO, C., RENZONI, A.
• Other Authors: Fossi, M. C., Massi, A., Lari, L., Marsili, L., Focardi, S., Leonzio, C., Renzoni, A.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 1995
• Subjects: bird; detoxification; feeding habit; Mixed-function oxidase activity; organochlorine; species at risk; Black-headed Gull; Larus ridibundus
• Online Access: http://hdl.handle.net/11365/18732; https://doi.org/10.1016/0269-7491(94)00098-X

The relationship between feeding habits and interspecies differences in the detoxication ability of the mixed function oxidase (MFO) system was investigated in birds. The role of MFO (particularly aldrin epoxidase activity) in the detoxication/bioaccumulation of organochlorines was also investigated. Euriphagic (yellow-legged herring gull (Larus cachinnans), black-headed gull (Larus ridibundus), jackdaw (Corvus monedula), magpie (Pica pica) and stenophagic (cormorant (Phalacrocorax carbo), coot (Fulica atra) and sparrow (Passer italiae)) species were collected in northern and central Italy. The following liver microsomal monooxygenase activities were measured: aldrin epoxidase, ethoxyresorufin dealkylation (EROD), benzyloxyresorufin dealkylation (BROD) and pentoxyresorufin dealkylation (PROD). NADPH-and NADH-cytochrome c reductase (NAD(P)H-CYT-CRED) and NADH-ferricyanide reductase (NADH-FERRIRED) activities were also measured in the liver microsomal fraction. Glutathione concentration (GSH) was measured in the liver cytosolic fraction. As a marker of liver damage γ-glutamyl transpeptidase (GGTP) activity was assayed in the serum. The residues of organochlorines (HCB, pp′DDTs and PCBs) were determined in muscle samples. Omnivorous species, particularly the yellow-legged herring gull, had the highest aldrin epoxidase activities. In the yellow-legged herring gull the activity was approximately twice as high as in the jackdaw (p < 0·05), black-headed gull (p < 0.05) and coot (p < 0·05). Values five times lower were detected in the specialist fish-eater, the cormorant (p < 0·001). The lowest values of aldrin epoxidase activity were detected in the sparrow. Feeding habits were found to be related to evolutionary interspecies differences in MFO activity. A significant statistical correlation (r = 0·656) was found between the 'omnivore index' and MFO detoxication activity expressed as aldrin epoxidation. Organochlorines, and particularly PCBs, were higher in cormorants and yellow-legged herring gulls from a ...