Wild Canada Geese Research Articles

Aquatic bird bornavirus 1 infection in a captive Emu (Dromaius novaehollandiae): presumed natural transmission from free-ranging wild waterfowl

ABSTRACTAn adult female emu (Dromaius novaehollandiae) presented with anorexia, maldigestion, weight loss, and various subtle nervous deficits. After four months of unrewarding diagnostics, treatments, and supportive care, the emu was euthanized due to lack of clinical improvement and progressive weight loss. Gross pathology revealed a very narrow pylorus and multiple flaccid diverticula of the small intestines. Histopathological findings included severe lymphoplasmacytic encephalomyelitis and multifocal lymphocytic neuritis associated with the gastrointestinal tract. Immunohistochemistry and polymerase chain reaction on the brain were positive for an avian bornavirus (ABV), and partial sequencing of the matrix gene identified aquatic bird bornavirus-1 (ABBV-1), 100% identical to viruses circulating in wild Canada geese (Branta canadensis). As wild geese frequently grazed and defaecated in the emu’s outdoor exhibit, natural transmission of ABBV-1 from free-ranging waterfowl to the emu was presumed to have occurred.

Investigation into the possibility of vertical transmission of avian bornavirus in free-ranging Canada geese (Branta canadensis)

To investigate the possibility of in ovo infection with avian bornavirus (ABV) in wild Canada geese (Branta canadensis), 53 eggs were opportunistically collected at various stages of embryonic development from 16 free-ranging goose nests at a large urban zoo site where ABV infection is known to be present in this species. ABV RNA was detected in the yolk of one of three unembryonated eggs using real-time reverse transcription polymerase chain reaction. ABV RNA was not identified in the brains from 23 newly hatched goslings or 19 embryos, nor from three early whole embryos. Antibodies against ABV were not detected in the plasma of any of the hatched goslings using an enzyme-linked immunosorbent assay. Possible reasons for the failure to detect ABV RNA in hatchlings or embryos include low sample size, eggs deriving from parents not actively infected with ABV, the testing of only brain tissue, and failure of the virus to replicate in Canada goose embryos. In conclusion, this preliminary investigation demonstrating the presence of ABV RNA in the yolk of a Canada goose egg provides the first evidence for the potential for vertical transmission of ABV in waterfowl.

Pathology and diagnosis of avian bornavirus infection in wild Canada geese (Branta canadensis), trumpeter swans (Cygnus buccinator) and mute swans (Cygnus olor) in Canada: a retrospective study

Nine hundred and fifty-five pathology cases collected in Ontario between 1992 and 2011 from wild free-ranging Canada geese, trumpeter swans and mute swans were retrospectively evaluated for the pathology associated with avian bornavirus (ABV) infection. Cases were selected based on the presence of upper gastrointestinal impaction, central nervous system histopathology or clinical history suggestive of ABV infection. The proportion of birds meeting at least one of these criteria was significantly higher at the Toronto Zoo (30/132) than elsewhere in Ontario (21/823). Central, peripheral and autonomic nervous tissues were examined for the presence of lymphocytes and plasma cells on histopathology. The presence of virus was assessed by immunohistochemistry and reverse transcriptase-polymerase chain reaction (RT-PCR) on frozen brains and on formalin-fixed paraffin-embedded tissues. Among selected cases, 86.3% (44/51) were considered positive on histopathology, 56.8% (29/51) were positive by immunohistochemistry, and RT-PCR was positive on 88.2% (15/17) of the frozen brains and 78.4% (40/51) of the formalin-fixed paraffin-embedded samples. Histopathological lesions included gliosis and lymphoplasmacytic perivascular cuffing in brain (97.7%), spinal cord (50%), peripheral nerves (55.5%) and myenteric ganglia or nerves (62.8%), resembling lesions described in parrots affected with proventricular dilatation disease. Partial amino acid sequences of the nucleocapsid gene from seven geese were 100% identical amongst themselves and 98.1 to 100% identical to the waterfowl sequences recently described in the USA. Although ABV has been identified in apparently healthy geese, our study confirmed that ABV can also be associated with significant disease in wild waterfowl species.

Detection and Characterization of a Distinct Bornavirus Lineage from Healthy Canada Geese (Branta canadensis)

Avian bornaviruses (ABV), identified in 2008, infect captive parrots and macaws worldwide. The natural reservoirs of these viruses are unknown. Reverse transcription-PCR (RT-PCR) was used to screen oropharyngeal/cloacal swab and brain samples from wild Canada geese (Branta canadensis) for ABV. Approximately 2.9% of swab samples were positive for bornavirus sequences. Fifty-two percent of brain samples from 2 urban flocks also tested positive, and brain isolates were cultured in duck embryo fibroblasts. Phylogenetic analyses placed goose isolates in an independent cluster, and more notably, important regulatory sequences present in Borna disease virus but lacking in psittacine ABVs were present in goose isolates.

Canada geese dispersed cultigen pollen grains from prehistoric Iroquoian fields to Crawford Lake, Ontario, Canada

Crawford Lake, Ontario, Canada (43°28.1' N, 79°56.9' W, 278 masl) has varved and AMS dated sediments containing fossil pollen that record native Iroquoian farming ca. AD 1268 to 1520. From before AD 1000 to 1268, bioturbating organisms caused poor varve preservation but since then, well‐preserved varves and dung pellets reflect anoxic bottom water due to meromixis. The onset of varve preservation coincides with the occurrences of pollen grains of Zea (maize), Helianthus (sunflower), Phaseolus (bean), Cucurbita (squash) and Portulaca (purslane), and spores of Ustilago cf. maydis (maize smut). These pollen grains and spores are more abundant in pellets between varve laminae than in the surrounding sediment matrix. Analyses of DNA from five pellets demonstrate that they are dung from wild Canada geese (Branta canadensis). In the autumn, as geese foraged in Iroquoian fields, they inadvertently ingested pollen and spores before flying to the lake. There they roosted and cast the pollen‐rich dung pellets, which became part of the sediment. This study demonstrates that birds, wild geese and perhaps ducks, can be important vectors of pollen to lake sediments located near agricultural settlements.

CANADA GEESE DISPERSED CULTIGEN POLLEN GRAINS FROM PREHISTORIC IROQUOIAN FIELDS TO CRAWFORD LAKE, ONTARIO, CANADA

Abstract Crawford Lake, Ontario, Canada (43°28.1′ N, 79°56.9′ W, 278 masl) has varved and AMS dated sediments containing fossil pollen that record native Iroquoian farming ca. AD 1268 to 1520. From before AD 1000 to 1268, bioturbating organisms caused poor varve preservation but since then, well-preserved varves and dung pellets reflect anoxic bottom water due to meromixis. The onset of varve preservation coincides with the occurrences of pollen grains of Zea (maize), Helianthus (sunflower), Phaseolus (bean), Cucurbita (squash) and Portulaca (purslane), and spores of Ustilago cf. maydis (maize smut). These pollen grains and spores are more abundant in pellets between varve laminae than in the surrounding sediment matrix. Analyses of DNA from five pellets demonstrate that they are dung from wild Canada geese (Branta canadensis). In the autumn, as geese foraged in Iroquoian fields, they inadvertently ingested pollen and spores before flying to the lake. There they roosted and cast the pollen-rich dung pelle...

Storage and incubation of Echinostoma revolutum eggs recovered from wild Branta canadensis, and their infectivity to Lymnaea tomentosa snails

Echinostoma revolutum eggs recovered from naturally infected wild Canada geese (Branta canadensis) were cold stored (4-6 degrees C) for up to 72 weeks. Successful hatching followed incubation for from 6 to 8 days at an optimum temperature of between 25 and 30 degrees C. A partial life cycle from adult worm to metacercarial encystment in Lymnaea tomentosa snails was completed in the laboratory. Snails were infected both by free miracidia and by ingestment of unhatched embryonated eggs. Infection was equally successful in environmental temperature ranges from 10 to 25 degrees C, and at challenge levels of 2, 5 or 10 embryonated eggs per snail. Exposure to 10 eggs was lethal. Ingestion by snails of embryonated eggs with successful infection at 10 degrees C suggests that embryonated eggs may be used to infect wild snails when the environmental water temperature has reached 10 degrees C.

A wild goose metapneumovirus containing a large attachment glycoprotein is avirulent but immunoprotective in domestic turkeys.

The genomic structure and composition of an avian metapneumovirus (aMPV) recently isolated from wild Canada geese (goose 15a/01) in the United States, together with its replication, virulence, and immunogenicity in domestic turkeys, were investigated. The sizes of seven of the eight genes, sequence identity, and genome organization of goose aMPV were similar to those of turkey aMPV subtype C (aMPV/C) strains, indicating that it belonged to the subtype. However, the goose virus contained the largest attachment (G) gene of any pneumovirus or metapneumovirus, with the predicted G protein of 585 amino acids (aa) more than twice the sizes of G proteins from other subtype C viruses and human metapneumovirus and more than 170 aa larger than the G proteins from the other aMPV subtypes (subtypes A, B, and D). The large G gene resulted from a 1,015-nucleotide insertion at 18 nucleotides upstream of the termination signal of the turkey aMPV/C G gene. Three other aMPV isolates from Canada geese had similarly large G genes, whereas analysis of recent aMPV strains circulating in U.S. turkeys did not indicate the presence of the goose virus-like strain. In vitro, the goose virus replicated to levels (2 x 10(5) to 5 x 10(5) 50% tissue culture infective dose) comparable to those produced by turkey aMPV/C strains. More importantly, the virus replicated efficiently in the upper respiratory tract of domestic turkeys but with no clinical signs in either day-old or 2-week-old turkeys. The virus was also horizontally transmitted to naïve birds, and turkey infections with goose 15a/01 induced production of aMPV-specific antibodies. Challenging day-old or 2-week-old turkeys vaccinated with live goose aMPV resulted in lower clinical scores in 33% of the birds, whereas the rest of the birds had no detectable clinical signs of the upper respiratory disease, suggesting that the mutant virus may be a safe and effective vaccine against aMPV infection outbreaks in commercial turkeys.

Characterization of avian metapneumoviruses isolated in the USA

Avian pneumovirus (APV; officially known as turkey rhinotracheitis virus) is an emergent pathogen of birds in the USA that results in upper respiratory tract disease in turkeys. Six years after the first outbreak in the USA, the disease continues to ravage turkey flocks, primarily in the state of Minnesota. From 1997 to 2000, the industry recorded losses estimated at 15 million US dollars per annum. Researchers have developed sensitive diagnostic techniques, including the enzyme-linked immunosorbent assay and the reverse transcriptase-polymerase chain reaction. which, when used together, are highly sensitive in detecting APV outbreaks in commercial turkey flocks. Phylogenetic analysis of the nucleotide and predicted amino acid sequence of 15 US viruses isolated between 1996 and 2000 demonstrated that the US viruses are relatively homogenous but different from the European APV subgroups A and B, resulting in the classification of US isolates into subgroup C. Infectious APV was isolated from sentinel waterfowls placed close to an infected commercial turkey farm and from wild Canada geese captured in Minnesota, suggesting that free-ranging birds may be involved in the spread of APV. Current efforts to prevent and control the infection include improving management and biosecurity practices and developing attenuated live and deletion mutant vaccines capable of conferring protection.

Proventricular Impaction Associated with Nonsuppurative Encephalomyelitis and Ganglioneuritis in Two Canada Geese

Two wild Canada geese (Branta canadensis) in an extremely emaciated state and with severe proventricular food impaction also had a nonsuppurative encephalomyelitis and ganglioneuritis. The condition in these two birds was morphologically similar to psittacine proventricular dilatation, a recently identified disease of psittacine birds.

Variation in Size of Eggs of Captive and Wild Canada Geese

Etude des causes majeures de la variation phenotypique observee dans la taille des œufs et la condition physique de la femelle. Cependant, le manque de variabilite de l'environnement entre les mesures empeche l'estimation de l'importance des differences genetiques

Annual contribution of carbon, nitrogen and phosphorus by migrant Canada geese to a hardwater lake

Each year more than 6,000 migrant Canada geese (Branta canadensis interior Todd) rest for 3 to 10 days during the months of March, October, November, and December on Wintergreen Lake, a productive 15 ha (33 acre) hardwater lake in the W. K. Kellogg Bird Sanctuary of Michigan State University in southwestern Michigan. For the past six years accurate weekly counts have been made of resident and migrant waterfowl using Wintergreen Lake. During the past four years Wintergreen Lake has been the site of extensive limnological investigations relating nutrient dynamics and primary productivity. These limnological investigations suggested nutrients contributed by migrant Canada geese were the chief cause of hypereutrophic primary productivity conditions in Wintergreen Lake. Until January 1970, the unpredictable habits of wild Canada geese using Wintergreen Lake prevented accurate estimation of nutrients contributed ton the lake in the form of goose feces. An opportunity to measure this source of nutrients was presented on 9 to 11 January 1970 when about 600 late fall migrant Canada geese rested part of three days in a clearly defined area on newly fallen snow covering frozen Wintergreen Lake. During their stay on the lake accurate records were kept of goose numbers, their location onmore » the lake surface, hours spent on the ice and hours spent feeding off the lake. After the geese left on 11 January 1970, a random sampling procedure was used to measure the density of droppings deposited within the area used by the geese on the lake surface.« less

The Occurrence of Gizzard Worms in Canada Geese

The roundworm parasite, genus Amidostomum, occurs as an adult under the horny lining of the avian gizzard. It was originally described from domestic geese in Germany by Zeder in 1800, and has since been reported as a cause of extensive losses among these birds in Europe. Typical symptoms are loss of appetite, anemia, and emaciation. This syndrome could result from the combined effects of loss of blood, toxic effect of parasite upon host, and digestive disturbances brought about by improper functioning of the diseased gizzard. The clinical pathology of the infection has been discussed by Bunyea and Creech (1926). The first North American record of an outbreak involving A. anseris in domestic geese came from New York State (Cram 1925, 1926). Since then outbreaks have been reported from Washington (Jerstad, 1936, and Adler and Moore, 1948), from Maryland (Farr and Wehr, 1952), and from Canada (Oliver, 1952, and McCraw, 1952). Gizzard worms were first reported from wild Canada geese (Branta canadensis) by O'Roke (1928) who recorded Amidostomum sp. from this host, and from several other species of native geese and ducks taken in California during the hunting season. In the summer of 1926 Wickware (1930, 1941) reported the occurrence of Amidostomum anseris in large numbers in several Canada goose goslings which died at a game sanctuary in western Ontario. Light infections with A. anseris were found by Jerstad (1937) in two Canada geese and a lesser Canada goose (Branta canadensis leucopareia) collected in the state of Washington. Wehr (1933) reported A. spatulatum from a Canada goose taken in New York State. Since 1948, we have had an opportunity to examine gizzards of a large s ries of Canada geese coming from several localities in the United States, but mostly from birds wintering along the coast of North Carolina. Part of the findings of these examinations have been published in a paper dealing with occurrence of Amidostomum anseris