Serological survey of Toxoplasma gondii in wild waterfowl in Chukotka, Kamchatka, Russia and Hokkaido, Japan

Antibodies to Toxoplasma gondii were assayed by ELISA in 22 experimentally inoculated domestic ducks. In addition, a serological assay was carried out at Obihiro, Hokkaido, Japan, in 2004 and 2005, on 221 wild ducks of 5 species: Anas platyrhynchus (n = 111); A. poecilorhyncha (n = 27); A. acuta (n = 58); A. penelope (n = 16); and A. crecca (n = 9). Assays were also conducted using sera from 197 wild geese of 2 species, i.e., Anser albifrons (n = 162) and Ans. fabalis (n = 35). Birds were collected between 2003 and 2005 from 3 different areas: Lake Miyajima-numa, Hokkaido, Japan, regions around Anadyr city of Chukotka autonomous okrug, and Lake Makobetukoe, Kamchatka oblast, Russia. The ELISA cutoff value (OD) was > or =0.395 based on results from uninfected ducks; the final dilution ratio recognized as positive was represented by the end titer. The end titer in the experimentally infected ducks ranged from 1:400 to 1:3,200. Antibodies to T. gondii were found in 49 of the 221 wild duck samples from Japan: A. platyrhynchus (22/74); A. poecilorhyncha (2/15); A. penelope (3/16); A. acuta (4/58); and A. crecca (0/9), all in 2004. In 2005, T. gondii was found in A. platyrhynchus (13/37); and A. poecilorhyncha (5/12). Thirty-two of 197 wild goose samples were seropositive, i.e., Ans. albifrons (7/51) in 2004 and (11/72) in 2005 in Miyajima-numa, Japan and 9/39 in Chukotka, Russia as well as in Ans. fabalis (5/35) in Kamchatka, for which the end titer ranged from 1:100 to 1:3,200. In immunoblotting, the A. platyrhynchus samples showed specific IgG antibody binding to several antigens in the T. gondii lane, i.e., at 30 and 43 kDa, but not in the Neospora caninum lane. No specific bands were noted in samples for which antibody activity was not detected. These results suggest that wild waterfowl inhabiting Hokkaido, Chukotka, and Kamchatka may be exposed to T. gondii.     

Lead poisoning.

Lead poisoning is the most common disease of environmental origin in the United States today. Adult lead poisoning results primarily from exposure by inhalation in the workplace. Pediatric lead poisoning results principally from the ingestion of lead from environmental media, including paint chips, dust, soil, drinking water, ceramics, and medications. Lead is toxic to many organ systems, among them developing erythrocytes, the kidneys, and the nervous system. Lead-induced toxicity to the central nervous system causes delayed development, diminished intelligence, and altered behavior. In young children, this effect has been demonstrated convincingly to occur at blood lead levels between 10 and 20 micrograms per dl. The Centers for Disease Control and Prevention has recommended that a blood lead level of 10 micrograms per dl or higher be considered evidence of increased lead absorption, and the National Academy of Sciences has concurred in that recommendation. Unresolved issues in need of further study include the frequency of screening young children for lead, the question of whether women should be offered screening for lead before conceiving a pregnancy, the role of x-ray fluorescence analysis in assessing lead in bone, and the appropriate legislative response of the United States government to lead-based paint abatement.     

Outbreaks of type C botulism in waterfowl in Japan

Four outbreaks of botulism in waterfowl were encountered over a five-year period of 1973 to 1977 in Japan. In all the outbreaks toxin was detected from all 12 sera, twenty-three of 24 gizzard contents from diseased or dead birds and one of three maggots. It was neutralized with Clostridium botulinum type C antitoxin serum, regardless of its origin. By using CO2 gas jet method, C. botulinum was isolated from four of 11 gizzards from diseased birds, five of 7 ones from dead birds, one of one maggot and one of one sludge sample, that is, eleven of 20 specimens in total. All 20 strains were identical with C. botulinum type C in biological properties. Most of the isolates showed a toxin titer ranging from 1,000 to 200,000 LD50 for mice. Four of them were identified as type C by mouse neutralization tests with antitoxin sera. The toxic suspensions of a strain 1-15 were administered orally to Chinese spot-billed ducks, which died when more than 200,000 LD50 mouse toxin was administered. Environmental conditions for occurrences of waterfowl botulism were discussed.     

Lead poisoning in zoo-dwelling primates

Lead intoxication was diagnosed in 42 primates at the National Zoological Park. Diagnoses were made clinically by the observation of signs of encephalopathy and the finding of 200 μg lead or more/100 ml blood, or postmortem by the presence of renal acid-fast intranuclear inclusion bodies and excess lead in liver specimens. Twenty-five of the primates had signs or lesions of lead encephalopathy. Lead poisoning was most common in the Cercopithecidae, and in the summer months. Lead encephalopathy was most frequent in juveniles. Leaded paint on the monkey cages was determined to be the source of poisoning. Blood studies revealed slight hypochromic anemia and immature and stippled erythrocytes. Postmortem lesions included acid-fast intranuclear inclusions in renal tubular and other epithelial cells; metaphyseal bone changes (lead lines); necrosis of striated muscle fibers; and other lesions. Treatment of one monkey for encephalopathy was attempted and proved successful.     

Lead poisoning in wild populations of Marsh Harriers Circus aeruginosus in the Camargue and Charente-Maritime, France

Lead poisoning of waterfowl, through the ingestion of spent gunshot, has been recognized as a mortality factor for over a century. However, in Europe relatively little attention has been paid to raptors that may ingest shot embedded in the flesh of prey. The present study examines the incidence of lead poisoning in wild Marsh Harriers Circus aeruginosus trapped at two sites in France, the Camargue and Charente-Maritime.
Eight captive Marsh Harriers (controls) had blood lead (PbB) concentrations of 5.3–10.8 μg per dl. Of 94 wild birds trapped during the winters of 1990/1991 and 1991/1992 either in baited clap traps or in mist nets at night roosts, 29 (31%) had elevated (>30 μg/dl) PbB concentrations and 13 (14%) had concentrations indicative of clinical poisoning (> 60 μg/dl). Similar percentages of birds caught using the two trapping methods had elevated (>30 μg/dl) PbB concentrations. However, clap netting appeared to select for more heavily contaminated birds and for juvenile birds, although the two are not necessarily correlated. In the Camargue, significantly more females than males trapped in clap nets had elevated PbB concentrations.
The incidence of shot in regurgitated Marsh Harrier pellets increased significantly between October and December, indicating increased exposure to lead as the hunting season progressed. There appeared to be a parallel increase in PbB concentrations throughout the hunting season, although this could not be clearly demonstrated as sex ratios were different during different sampling periods.
Elevated PbB concentrations of harriers in the Camargue are likely to result primarily from the ingestion of shot in the flesh of crippled or unretrieved waterfowl and in Charente-Maritime, from eating crippled or dead mammals.
Other raptors at risk from lead poisoning and solutions to this problem are discussed.     

Pasteurella anatipestifer as a cause of mortality in captive wild waterfowl

An outbreak of Pasteurella anatipestifer infection in young wild waterfowl at the Niska Waterfowl Research Center resulted in losses of approximately 100 Blue and Snow Geese, one White-fronted Goose, five Mandarin Ducks, one Black Duck and one Wood Duck. Clinical signs included diarrhea, paralysis and tremors. Gross lesions were fibrin deposits on serosal surfaces, hemorrhages on the epicardium, consolidation of the lungs, cloudy or flaky deposits on the air sacs, and dark, swollen spleens. Microscopic lesions included fibrinous meningitis, pneumonitis, air saculitis and serositis. Swollen leg and foot joints were seen in some cases. Chloramphenicol treatment seemed to be of benefit in controlling the outbreak.     

White phosphorus poisoning of waterfowl in an Alaskan salt marsh.

The cause of the yearly death of an estimated 1,000 to 2,000 migrating dabbling ducks (Anas spp.) and 10 to 50 swans (Cygnus buccinator and C. columbianus) has remained a mystery for the last ten years in Eagle River Flats (ERF), a 1,000 ha estuarine salt marsh near Anchorage, Alaska, used for artillery training by the U.S. Army. We have gathered evidence that the cause of this mortality is the highly toxic, incendiary munition white phosphorus (P4). The symptoms of poisoning we observed in wild ducks included lethargy, repeated drinking, and head shaking and rolling. Death was preceded by convulsions. Farm-reared mallards dosed with white phosphorus showed nearly identical behavioral symptoms to those of wild ducks that became sick in ERF. White phosphorus does not occur in nature but was found in both the sediments where dabbling ducks and swans feed and in the gizzards of all carcasses collected in ERF. We hypothesize that feeding waterfowl are ingesting small particles of the highly toxic, incendiary munition P4 stored in the bottom anoxic sediments of shallow salt marsh ponds.     

Lead poisoning in woodpeckers in Sweden

Lead poisoning was demonstrated in two gray-headed woodpeckers (Picus canus) and one white-backed woodpecker (Dendrocopus leucotos) in Sweden; they had liver lead levels between 9.4 and 26.2 mg(-1) wet weight. At necropsy one gray-headed woodpecker showed signs of emaciation and the other one had severe traumatic injuries, caused by a cat. The white-backed woodpecker died in the transportation box during a translocation program. The source of the lead could not be determined, but it was suspected that it may have originated from lead pellets shot into trees and picked out by the woodpeckers during food search.     

Mercury poisoning in a wild mink

Mercury poisoning was diagnosed in a clinically-ill wild mink (Mustela vison) on the basis of clinical signs, histopathologic lesions and tissue mercury concentrations. The probable source of mercury was through ingestion of fish from the nearby South Saskatchewan River which is known to be contaminated with mercury. This is believed to be the first documented case of mercury intoxication of a wild animal in North America.     

Lead poisoning in whooper and tundra swans

Six weak whooper swans (Cygnus cygnus) and two weak tundra swans (Cygnus columbianus) were found at Swamp Miyajima (Hokkaido, Japan) in May 1998. Anorexia, depression, green watery feces, pale conjunctiva, and anemia were observed. Radiographs showed from six to 38 suspected lead pellets in the gizzard. Blood lead concentrations were 2.5-6.7 microg/g (mean+/-SD=4.6+/-1.14 microg/g) on day 1. After blood collection, the birds were treated with calcium disodium ethylenediaminetetraacetate (CaEDTA) given intravenously and force fed. Despite treatment, seven birds died the next day. Green, bile-stained livers and pale or green kidneys were observed on necropsy. Microscopically, bile pigment was widespread in the liver and acid-fast intranuclear inclusion bodies were observed in renal tubular epithelium. Lead concentrations in livers and kidneys were 14.0-30.4 microg/g and 30.2-122 microg/g wet weight, respectively. Only one bird survived and this whooper swan continued to be treated with CaEDTA and activated charcoal. No lead shot was observed in the proventriculus and gizzard by radiography on day 64 and the blood lead concentration decreased from 2.9 microg/g to 0.09 microg/g during that same period. After 4 mo of rehabilitation, the whooper swan was returned to the wild. Lead intoxication continues to be a problem at Swamp Miyajima.     

Lead poisoning in a northern bobwhite in Georgia

A northern bobwhite (Colinus virginianus) was observed with partial paralysis on 3 March 1997 and found dead on 8 March 1997 on Di-Lane Plantation Wildlife Management Area (Burke County, Georgia, USA). The juvenile male was necropsied by the Southeastern Cooperative Wildlife Disease Study (Athens, Georgia) and diagnosed with lead toxicosis. The bobwhite had liver tissue lead levels of 399 parts per million wet weight and two worn 1-mm diameter lead shot pellets were found in the gizzard.     

Thallium contamination in wild ducks in Japan

Although thallium (Tl) is toxic to both humans and animals, there is little information on contamination in wildlife. In this study, Tl contents in wild ducks in Japan were determined. Contents of Tl in kidney and liver ranged from 0.42 to 119.61 and 0.10 to 33.94 microg/g dry weight, respectively. Significant correlations between Tl contents in kidney and liver were observed for all dabbling ducks except mallard (Anas platyrhynchos); similar correlations were not observed in diving ducks. Variation in Tl content was observed between sampling locations with the highest mean Tl content in the Eurasian wigeon (Anas penelope) collected in Ibaraki Prefecture.