Emaciation and larval filarioid nematode infection in boreal owls (Aegolius funereus).

Microfilariae are considered non-pathogenic in wild birds. The objective of the current communication is to report host reactions to microfilarial infection of unusual intensity in emaciated boreal owls (Aegolius funereus). An unusually large number of boreal owls (n = 21) were submitted to the Canadian Cooperative Wildlife Health Center-Quebec Region for post-mortem examination during the winter of 2009. Nineteen out of 21 birds were considered emaciated based on atrophy of adipose tissue and pectoral muscles and suboptimal weight. A microscopic examination of a subset of nine owls revealed the presence of microfilariae in six owls. Three of the birds with a heavy parasite burden had masses of larval nematodes obstructing large vessels of the lungs. The emaciated owls are believed to have died from starvation due to a cyclic decrease in prey abundance in the boreal forest. This cycle also drives winter movements of boreal owls to urbanized areas of southern Quebec, presumably accounting for the large number of birds submitted in 2009. In the most severely infected owls, the extreme microfilarial burden might have caused an alteration in circulatory dynamics, gaseous exchanges and also probably some metabolic cost. Consequently, microfilariae could have significantly contributed to the death of some of these owls.

Anatomic and molecular characterization of the endocrine pancreas of a teleostean fish: Atlantic wolffish (Anarhichas lupus).

BACKGROUND: The biologic attributes of the endocrine pancreas and the comparative endocrinology of islet amyloid polypeptide (IAPP) of fish are not well described in the literature. This study describes the endocrine pancreasof one teleostean fish. Ten captive Atlantic wolffish (Anarhichas lupus)from the Montreal Biodome were submitted for necropsy and their pancreata were collected. RESULTS: Grossly, all the fish pancreata examined contained 1-3 nodules of variable diameter (1-8 mm). Microscopically, the nodules were uniform, highly cellular, and composed of polygonal to elongated cells. Immunofluorescence for pancreatic hormones was performed. The nodules were immunoreactive for insulin most prominent centrally, but with IAPP and glucagon only in the periphery of the nodules. Exocrine pancreas was positive for chromogranin A. Not previously recognized in fish, IAPP immunoreactivity occurred in α, glucagon-containing, cells and did not co-localize with insulin in ß cells. The islet tissues were devoid of amyloid deposits. IAPP DNA sequencing was performed to compare the sequence among teleost fish and the potency to form amyloid fibrils. In silico analysis of the amino acid sequences 19-34 revealed that it was not amyloidogenic. CONCLUSIONS: Amyloidosis of pancreatic islets would not be expected as a spontaneous disease in the Atlantic wolffish. Our study underlines that this teleost fish is a potential candidate for pancreatic xenograft research.

Natural West Nile virus infection in a captive juvenile Arctic wolf (Canis lupus).

A case of West Nile virus (WNV) infection in a captive 4-month-old Arctic wolf (Canis lupus) is described. The animal had vomiting, anorexia, and ataxia before death. Histopathology revealed multifocal severe renal lymphoplasmacytic vasculitis, mostly affecting small arterioles, with fibrinoid degeneration of some vessel walls. Many small foci of gliosis were detected in the cerebral cortex. West Nile virus was demonstrated in the kidneys and cerebrum by immunohistochemistry and polymerase chain reaction. The described renal changes represent a novel pathological finding of WNV infection.

Reproductive and morphological effects of halogenated dimethyl bipyrroles on captive American kestrels (Falco sparverius).

Sixty-four adult captive American kestrels (Falco sparverius) were exposed to a dietary source of halogenated dimethyl bipyrroles (HDBPs), a group of organohalogens proposed to have a natural origin. Adult kestrels were assigned to four treatment groups that were administered a different dose of HDBPs [high, 140 microg/(bird x d); medium, 4.3 microg/(bird x d); low, 0.13 microg/(bird x d); control, 0 microg/(bird x d)]. Exposure began prior to pairing and continued during breeding until approximately 28 d after hatching of the final eggs. Juvenile and adult kestrels accumulated HDBPs in carcass tissue, plasma, and liver. In addition, HDBPs were transferred to yolks during egg development. Low dietary absorption efficiencies (0.011-0.029) indicated that HDBPs were effectively cleared from kestrels either from increased elimination, metabolism, or a combination of the two processes. Reproductive and morphological endpoints examined for HDBP-induced changes included egg volume, egg mass, eggshell thickness, egg fertility, clutch size, liver and whole body mass, antebrachium, central retrice, tarsus, ninth primary, and wing cord lengths. Few statistically significant dose-dependent effects were observed. Hepatic tissue samples from selected individuals underwent histomorphological evaluation. Although the hepatic function was not evaluated specifically in these birds, no clinical signs suggestive of liver disease or gross hepatic anomalies were observed. Only minor histomorphological changes were detected in the hepatic tissue. The lack of serious effects suggests that HDBPs are not an acute reproductive threat to avian populations.