Ectoparasites of a population of urban gray squirrels in northern Florida.

Ectoparasites infesting a population of urban gray squirrels (Sciurus carolinensis Gmelin) in northern Florida were collected monthly during 1974. Eleven species were identified: one flea (Orchopeas howardi (Baker], three suckling lice (Enderleinellus longiceps Kellogg & Ferris, Hoplopleura sciuricola Ferris, and Neohaematopinus sciuri Jancke), one tick (Dermacentor variabilis Say), two mesostigmatid (gamasid) mites (Androlaelaps casalis (Berlese) and A. fahrenholzi (Berlese], and four chiggers (Eutrombicula alfreddugesi (Oudemans), E. splendens (Ewing), Leptotrombidium peromysci Vercammen-Grandjean & Langston, and Parasecia gurneyi (Ewing]. The flea and three suckling lice represent core species of ectoparasites for the gray squirrel; the remainder are probably satellite species. Only E. longiceps varied significantly in prevalence or intensity of infestation among host age groups; subadult squirrels had higher intensities than adults. Peak prevalence of O. howardi occurred in January and attained maximum intensity in March, whereas both prevalance and intensity were minimum in August. Prevalence of H. sciuricola was maximum in November and remained at similar levels through June. It then declined significantly to its minimum in September-October. Intensity of infestation, however, was greatest in August, September, and January. Maximum prevalence of N. sciuri occurred from January to March and was minimum in September; intensity of infestation reached maxima in January, June, and August.

Ectoparasites (Acari, Mallophaga, Anoplura, Diptera) of white-tailed deer, Odocoileus virginianus, from southern Florida.

During a 7-yr period (1984-1990), 300 white-tailed deer, Odocoileus virginianus (Zimmermann), from 7 localities in Collier, Dade, and Monroe counties in southern Florida were examined for ectoparasites. Eight species were identified: 4 ticks [Ixodes scapularis Say, I. affinis Neumann, Amblyomma maculatum (Koch), and Dermacentor variabilis (Say)], 1 chigger mite [Eutrombicula splendens (Ewing)], 1 ked (Lipoptena mazamae Rondani), 1 chewing louse [Tricholipeurus lipeuroides (Megnin)], and 1 sucking louse [Solenopotes binipilosus (Fahrenholz)]. The most widely distributed and prevalent species were the deer ked L. mazamae and the blacklegged tick I. scapularis, both of which occurred in all 7 localities, in all years, and in all age classes of deer. Their overall prevalences were 82 and 22%, respectively. The prevalence of L. mazamae varied significantly by month. L. mazamae should be considered a core ectoparasite species of white-tailed deer in southern Florida because of its specificity, distribution, and high prevalence.

Cysticerci (Cestoda: Taeniidae) from white-tailed deer, Odocoileus virginianus, in southern Florida.

Metacestodes (cysticerci) of Taenia omissa Lühe, 1910, and Taenia hydatigena Pallas, 1776, were found in 9 and 1 of 124 white-tailed deer, respectively, in southern Florida in 1984-1986. Intensities of T. omissa varied from 1 to 15 (mean = 4.6); only 1 cysticercus of T. hydatigena was collected. No significant difference in the prevalences of T. omissa according to sex, age, or locality was observed.

Haemoproteus meleagridis Levine 1961: redescription and developmental morphology of the gametocytes in turkeys.

Haemoproteus meleagridis Levine 1961 is redescribed and illustrated from material obtained from wild and domestic turkeys (Meleagris gallopavo) in Florida and Georgia. The mature gametocyte of this haemoproteid surrounds the erythrocytic nucleus, occupies 80 to 90% of the host-cell-parasite complex, and causes atrophy of the host cell's nucleus and hypertrophy of the host cell. The developmental sequence of H. meleagridis was studied critically. Following the entry of merozoites into the erythrocytes, they grew into halteridial and then circumnuclear forms. This was followed by a 10- to 13-day period during which trophozoites were not detectable by blood smear, and after which, the trophozoites returned to the peripheral circulation.

Helminths of the Florida manatee, Trichechus manatus latirostris, with a discussion and summary of the parasites of sirenians.

We examined 215 Florida manatees (Trichechus manatus latirostris) at necropsy to determine the helminth fauna. Six species were identified: Heterocheilus tunicatus (Nematoda: Ascaridoidea); Anoplocephala sp. (Cestoda: Cyclophyllidea); and 4 species of trematodes, Cochleotrema cochleotrema (Digenea: Opisthotrematidae), Chiorchis fabaceus (Digenea: Paramphistomatidae), Nudacotyle undicola (Digenea: Nudacotylidae), and Moniligerum blairi (Digenea: Opisthotrematidae). Seventy-three percent of the manatees examined were infected with at least 1 species of helminth. The mean number of species of helminths per infected manatee was 1.9 with a range of 1-4. Fifty-nine manatees were helminth-free; 30 of these were calves. No associations were found between the intensity of helminth infections and host sex, age class, season, and geographic location of recovery, or cause of death. Differences in parasite prevalence between age classes were highly significant for Chiorchis, Cochleotrema, and Heterocheilus, due to a low number of infected calves. A higher prevalence of Cochleotrema was found in manatees recovered from eastern Florida, and Heterocheilus was evident in significantly more manatees from western and souther Florida. Comparisons in the parasite fauna are made among Florida manatees and other sirenian populations, and a brief review of sirenian parasites is included.

Pathogenicity of Haemoproteus meleagridis (Haemosporina: Haemoproteidae) in experimentally infected domestic turkeys.

Sporozoite-induced experimental infections of Haemoproteus meleagridis produced a moderate to severe myositis and significant effects on weight gain and growth in domestic turkey poults. Pathological effects occurred in both low- and high-dose infections (4,400 and 57,500 sporozoites, respectively). Low-dose birds weighed significantly less than controls at 3 wk postinfection (PI) when peripheral parasitemia reached a peak and had significantly shorter tarsometatarsal lengths at both 1 and 3 wk PI. High-dose birds were significantly lighter and smaller than control and low-dose birds throughout the course of the 8-wk study. Infected birds were not anemic in spite of high parasitemias that often exceeded 50% of circulating erythrocytes. The most serious pathological effects occurred prior to patency and were associated with development of megaloschizonts in skeletal muscle. Microscopic lesions in 4 high-dose birds that died between 19 and 22 days PI were characteristic of a severe, acute hemorrhagic myositis. Megaloschizonts were surrounded by a hemorrhagic inflammatory infiltrate composed of macrophages, heterophils, giant cells, and red blood cells. Muscle fibers adjacent to megaloschizonts were swollen, hyaline, and contained prominent calcium deposits. Other observations included enlargement of the spleen, deposition of pigment in macrophages of the lung and spleen, and secondary bacterial and fungal infections in the intestine and lungs. Necrotic and calcified muscle fibers and degenerating megaloschizonts were still present at 8 wk PI when the experiment ended. Our results demonstrated significant pathological changes in H. meleagridis-infected domestic turkeys that were associated primarily with preerythrocytic stages of development.

Status of the genus Cyrnea (Nematoda: Spiruroidea) in wild turkeys from the southeastern United States.

Two species of Cyrnea are reported from 706 wild turkeys (Meleagris gallopavo) from 25 localities in 9 southeastern states. Cyrnea (Cyrnea) neeli sp. n. in birds from Alabama and Florida is differentiated primarily by distal processes of the left spicule and spicule lengths. Specimens from wild turkeys previously reported as C. eurycerca are identified as C. coloni. The configuration of caudal papillae of C. colini is redescribed. Neither species occurred in birds from montainous regions, and C. neeli sp. n. was restricted to Florida and southern Alabama. Poults less than 1-month old were not infected. Infections peaked in early fall and then declined rapidly.

Experimental transmission by mosquitoes of Plasmodium hermani between domestic turkeys and pen-reared bobwhites.

Plasmodium hermani was experimentally transmitted from domestic turkey poults (Meleagris gallopavo) to pen-reared bobwhites (Colinus virginianus) and then from these bobwhites back to domestic turkey poults. Transmission was achieved by Culex nigripalpus both by bites of the mosquito and by intraperitoneal injection of sporozoites. All of the 23 bobwhites and the 13 turkeys exposed to sporozoites became infected. These results indicate that the bobwhite might be a reservoir host for this malaria of wild turkeys in nature.

Coccidia of sandhill cranes, Grus canadensis.

Eimeria gruis Yakinoff and Matschoulsky 1935, Eimeria reichenowi Yakimoff and Matschoulsky 1935, and an Adelina species are described from sandhill cranes in the United States. E. gruis was found in the feces of 11 of 14 Florida sandhill cranes (Grus canadensis pratensis) and 62 of 72 greater sandhill cranes (G. c. tabida) from Florida, 5 of 14 greater sandhill cranes from Arizona, and 4 of 16 lesser sandhill cranes (G. c. canadensis) from Texas. E. reichenowi was found in the feces of 12 of 14 Florida sandhill cranes and 66 of 72 greater sandhill cranes from Florida, 4 of 14 greater sandhill cranes from Arizona, and 5 of 16 lesser sandhill cranes from Texas. Adelina sp. was found in the feces of 3 of 14 Florida sandhill cranes and 2 of 72 greater sandhill cranes from Florida. The Adelina species is considered to be a spurious parasite of the cranes.

A species of Plasmodium from sandhill cranes in Florida.

Infections of a species of Plasmodium (subgenus Giovannolaia) were diagnosed in 3 sandhill cranes (Grus canadensis) from north-central Florida. This parasite is close morphometrically to Plasmodium polare; this finding constitutes the first report of a species of Plasmodium from sandhill cranes in North America.

A haemogregarine from the American alligator (Alligator mississippiensis).

Haemogregarina crocodilinorum Börner 1901 is redescribed from the blood of the American Alligator (Alligator mississippiensis). Gametocytes occurred in erythrocytes and erythrocytic schizonts contained about eight merozoites (range, 6--12). Gametogony and sporogony occurred in the gut of the leech, Placobdella multilineata and intracellular, unisporocystic oocysts were found within epithelial cells of the leech's intestinal wall. Presumed sporozoites were present in the intestinal contents. Attempts to transmit the parasite via leeches failed. The haemogregarine was widely distributed in southern United States and was found in 77 (59%) of 130 alligators examined. A comparison of this parasite is made with other haemogregarines reported from crocodilian reptiles.

Intestinal coccidia of white-tailed deer in southern Florida.

From 1984 to 1986 110 white-tailed deer (Odocoileus virginianus) from Big Cypress National Preserve in southern Florida were examined for intestinal coccidial infections. Three species of Eimeria (E. mccordocki, E. madisonensis, and E. odocoilei) were found in low prevalences. There were no differences in prevalence due to age, sex, season of collection or specific locality within the Preserve.

Hemoparasites of raccoons (Procyon lotor) in Florida.

Four hemoparasite species (Babesia lotori, Trypanosoma cruzi, Dirofilaria tenuis and Mansonella llewellyni) were found in raccoons (Procyon lotor) collected from 1972 to 1974 in Duval (n = 14) and Collier (n = 170) counties, Florida (USA). Trypanosoma cruzi was found in thin blood smears from one raccoon at each locality. The prevalence of B. lotori was 79% and 80% in samples taken in December 1973 in Collier and Duval counties, respectively. No patent infections by B. lotori were detected in raccoons collected in Collier County in December 1972, but 42% of the raccoons examined in September 1973 were infected. In Collier County there were no significant differences in the prevalence of B. lotori by host sex or age. In Duval County, overall D. tenuis prevalence was 7%, whereas that of M. llewellyni was 14%; the latter species was not found in Collier County. Adult raccoons had a significantly greater prevalence of D. tenuis (32%) than did subadults and juveniles (7%), and male raccoons showed a significantly greater prevalence (51%) than did females (8%).

Antimicrobial resistant Salmonella spp. isolated from double-crested cormorants (Phalacrocorax auritus) and common loons (Gavia immer) in Florida.

Antimicrobial resistant Salmonella spp. were found in double-crested cormorants and common loons in Florida. Single or multiple resistance occurred in all Salmonella agona isolates from cormorants, primarily to ampicillin, sulfonamids, streptomycin, neomycin, and kanamycin. Similar patterns of resistance were found in S. agona isolates from common loons. In addition, isolates of S. Saint paul from loons were found resistant to tetracycline and streptomycin, while 2 of 7 isolates of S. infantis were resistant to tetracycline only.

Blood parasites of some columbiform and passeriform birds from Chile.

Ninety-one birds of 23 species from Chile were examined for haematozoa; 13 birds of seven species harbored species of Haemoproteus, Leucocytozoon, Plasmodium, Trypanosoma and microfilariae. Haemoproteids (representing four species) were the most common parasites and occurred in 10 of the 13 infected birds.

Influence of rainfall on lungworm infections in bighorn sheep.

From 1959 through 1968, lungs from 124 Rocky Mountain bighorn sheep (Ovis c. canadensis) from the Sun River herd in western Montana were examined for lungworm infections. All lungs were infected with Protostrongylus stilesi and 104 (84%) contained concurrent infections of P. stilesi and P. rushi. Significant correlations were observed between levels of lungworm infection and total rainfall during April, May, and June of each year. An explanation of this in terms of terrestrial snail (intermediate host) populations and a suggestion for the possible use of these data in developing a predictive model for forecasting lungworm levels for use in in bighorn sheep management are given.

Haematozoan parasites of mourning doves in Florida.

A total of 918 mourning doves ( Zenaida macroura ) collected from six localities in Florida over a three year period (1973-1976) was examined for haematozoan infections. Three species of haematozoans were encountered: Haemoproteus maccallumi (92% prevalence), H. sacharovi (3% prevalence), and Leucocytozoon marchouxi (0.1% prevalence). No trypanosome or Plasmodium infections were found. Adult doves did not show sexually or seasonally-related differences in infection intensity. Immature doves, however, had parasitemias which showed cyclic seasonal fluctuations, but since these decreased with age, this seasonal fluctuation was interpreted to be due to changes in age composition of the population and not season itself. Doves from northern Florida showed significantly lower parasitemias than doves from the southern part of the state.

Pathogenesis of Eustrongylides ignotus (Nematoda: Dioctophymatoidea) in Ciconiiformes.

Natural (n = 157) and experimental (n = 5) infections with the nematode Eustrongylides ignotus are described for ciconiforms collected in Florida (USA). Larvae perforated the ventriculus in 3 to 5 hr and caused hemorrhage and bacterial peritonitis that sometimes progressed to a fibrous peritonitis with extensive adhesions. Severity of the disease was related inversely to the age of the bird and directly to the number of parasites involved. Some infections in adult birds were resolved. As a consequence of eustrongylidosis, anorexia and behavioral abnormalities resulted in emaciation and may have predisposed birds to traumatic death. Host-parasite adaptations apparently were not adequate for nestling ciconiforms as death of nestlings usually occurred before infections become patent (longer than 14 days, less than 23 days). Patent infections were found in both color morphs of the great blue heron (Ardea herodius), and in great egrets (Casmerodius albus) and snowy egrets (Egretta thula). We propose that birds of the family Ardeidae are the primary definitive hosts.

Interrelationships of parasites of white-winged doves and mourning doves in Florida.

The parasites of indigenous populations of mourning doves (Zenaida macroura) in north and south Florida were compared with those of an introduced population of white-winged doves (z. asiatica) in south Florida. Thirty-two species of parasites including 5 protozoans, 7 nematodes, 2 trematodes, 2 cestodes, 7 acarines, 7 mallophagans, and 2 dipterans were found. Of these, 16 common to both species of doves. Mourning doves from north Florida showed a more diverse parasite fauna than did the white-winged or mourning dove populations from south Florida. Nematodes were the most common parasites in all three populations; infected doves contained one or two nematode species per dove. Total helminth burdens per infected dove averaged 13.1 for white-winged doves, 19.9 for mourning doves in south Florida, and 6.6 for mourning doves in north Florida. The prevalence of infections by Trichomonas gallinae was higher in white-winged doves (97%) than in mourning doves in south Florida (17%) or in mourning doves in north Florida (1%). The high prevalence of this parasite in expanding populations of white-winged doves may pose a threat to mourning dove populations since some strains of T. gallinae are pathogenic.

Myopathy associated with megaloschizonts of Haemoproteus meleagridis in a wild turkey from Florida.

Necropsy of an emaciated adult wild turkey (Meleagris gallopavo osceola) that died in captivity soon after capture revealed numerous macroscopic 1-2 mm white cysts in the pectoral muscles. Microscopic, aseptate protozoan megaloschizonts, 50-150 microns in diameter, corresponded to the cysts in histological sections. The megaloschizonts were surrounded by a thick, hyaline wall and packed with spherical merozoites less than 1 micron in diameter. Muscle fibers surrounding most of the megaloschizonts exhibited early signs of dystrophic calcification. The fibers were swollen, pale and hyaline and contained scattered basophilic granules. The megaloschizonts were morphologically distinct from sarcocysts of Sarcocystis sp. and Besnoitia sp. and the thin-walled tissue cysts of Toxoplasma gondii. They were identical in structure and host reaction to the second-generation megaloschizonts of Haemoproteus meleagridis, reported previously from experimentally infected domestic turkeys. While the precise cause of death of the wild turkey could not be determined, the most prominent lesions were associated with the numerous intramuscular megaloschizonts.