Examination of blood films from wood ducks (Aix spo7ssa) from several northeastern states revealed Haemovproteus, Leucocytozoon, Plasmodium and a trypanosome. Haemoproteus occurred in all areas sampled and birds of the year from Massachusetts demonstrated the highest incidence during the last 2 weeks in August. Leucocytozoon was most prevalent in more northern areas. P. circllmflexllm and a trypanosome are reported for the first time from this host. BLOOD PARASITES OF WOOD DUCKS * Herman et al . 119 and to urinary lead exeretion. Am. J. Clin. Pathol. 50 ( 3 ): 291-301. ROSEN, M. N., AND R. A. BANKOWSKI. 1960. A diagnostic technique and treatment for lead poisoning in swans. California Fish and Game 46( 1 ) :81-90. WATSON, R. JANET, ELIZABETH DECKER, AND H. C. LICHTMAN. 1958. Hematologic studies of children with lead poisoning. Pediatrics 21(1): 4056. WHITAKER, JO ANNE, AND TERESA J. VIETTI. 1959. Fluorescence of the erythrocytes in lead poisoning in children: an aid to rapid diagnosis. Pediatrics 24 ( 4 ): 734-738. WOBESER, G. 1969. Apparent favourable response of lead poisoning in a duck to treatment svith a chelating agent. Wildl. Disease Assoc. Bull. S(2 ) :120. Received for publication March 31, 1970. Plasmodium, Leucocytozoon, and Haemoproteus, occurring in the blood of birds, have also been reported from the wood duck ( Herman 1963 ) . This report extends our knowledge of the prevalence of these parasites in this host species. The authors are indebted to William L. Miller, David Grice, Clark G. Webster, William C. Good, Frank McCilvrey, David Hickok, and Terry W. Johnson, who supplied blood smears, or otherwise cooperated in obtaining specimens that formed the basis for this report. MATERIAL AND METHODS Most blood films were obtained by the puncture of a vein in the wing or toe and were stained with Giemsa's stain. Approximately 20,000 red blood cells (RBC) on each film were examined microscopically with the oil immersion objective (970 x ). Samples included 3S5 blood films from 230 birds from Massachusetts in 1952, and one film from each of the following: 128 and 198 birds, 1952 and 1953, respectively, Vermont; 13 birds, Maine, 1956; 35, Ohio, 1964; 173, New York, 1965; and 114, Patuxent Wildlife Research Center, Maryland, 1965. In addition, blood samples from seven adult wood ducks captured in their nest boxes at the Patuxent Wildlife Research Center on April 21 and A4ay l and 2, 1952, were inoculated into duck embryos following the technique of McChee ( 1949, as in Eichorn 1940). During the summer of 1965, blood samples were obtained from 42 wood ducks at the Patuxent Center and subinoculated, intramuscularly, into mallard ducklings ranging in age from a few days to several weeks. Blood films were taken from the mallards three times a week for at least 60 days following injection, and examined for evidence of Plusmodium. This content downloaded from 157.55.39.135 on Sun, 03 Jul 2016 05:46:00 UTC All use subject to http://about.jstor.org/terms Table 1. Blood parasites from wood ducks. NO. BIRDS H or LOCATION EXAMINED H Sb 12 S0 P P T Maine 1956 13 11 85 9 69 (} O O Massachusetts 1952 230 88 38 1 18 6 0 Vermont 1952 128 18 14 0 3 1 1 Vermont 1953 198 48 24 0 2 0 0 New York 196S 16 0 0 0 0 0 New York 1965 157 13 8 0 0 0 0 Ohio 1964 35 15 43 1 0 0 0 Patuxent Center 1965 114 13 11 0 0 0 0 120 Jo?lrnal of Wildltfe Management, Vol. 35, No. 1, January 1971 from 4, and six from 1 bird. Although these multiple films were obtained at intervals throughout the period, a number of ducks including the bird from which sis films were made, remained negative. Several birds were negative in one or more examinations axld positive in others, either beconing infected during the interim or losing the parasitemia. Some birds were positive at each examination, the longest duration being a month from first to last sample. Plasmodium was observed only in smears of birds from Massachusetts and Vermont. Eighteen of the ducks from Massachusetts were infected. In addition, six birds had young parasites that could not be differentiated from Haemoproteus and may have been P1usmodium. On only one of the birds from Massachusetts was a specific diagnosis possible. Round, mature schizonts, svith 12 merozoites, together with the characteristic round gametocytes displacing the hostcell rlucleus, led us to classify this infection as P. relictum. In the other 17 infections, developing segmenters were observed but insufficient forms were present to pernit a species diagnosis. Many of these wood ducks were also infected with Haemoproteus, which has gametocytes very similar to those of P. circumflexum. However, without the confirming evidence of mature schizonts, diagnosis as P. circumfilexum sras not justified. Plasmodillm was not observed in more than one film of a bird when additional smears were made on other dates. The bird with P. relictum was positive on July 16. Most infections were observed in late August or early September. Irlfections were low level7 with less than 10 parasites per 10,000 RBC. Of the five infections with Plusmodium observed in birds from Vermont, orle was diagnosed as P. relictum, three as P. circumflexum, and one as P. sp. The elongate a = June. b = August-September. H = Haemoproteus, L diu771, T = trypanosomes. Leucocytozoorw, P