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PubMed1995

Tannic acid's effect on bird antigen.

BACKGROUND: Birds have been associated with many diseases including hypersensitivity pneumonitis and allergic diseases such as asthma and rhinitis. Bird antigen from homes of patients with hypersensitivity pneumonitis persists long after the bird is removed from the home. This may account for the persistence of symptoms, signs, and bird-specific IgG in patients with hypersensitivity pneumonitis. Tannic acid application has been effective in decreasing cat and mite allergen levels. No data have been available on tannic acid's effect on bird antigen. OBJECTIVE: It is the purpose of this study to determine whether tannic acid reduces bird antigen in the home. METHOD: Dust samples were collected from homes with bird antigen before and after application of tannic acid. Samples were assayed for bird antigen levels using a competitive inhibition ELISA. Pre- and post-bird antigen levels were compared using a paired t test to determine whether antigen was reduced significantly. RESULTS: There was not a statistical difference between bird antigen levels before and after application of tannic acid as compared by paired t test (P = .09). CONCLUSION: Tannic acid is not effective in decreasing bird antigen levels. In patients with hypersensitivity pneumonitis or allergic disease to birds, the bird should be removed from the home and environmental cleanup should be undertaken, but tannic acid application is not indicated.

Allergens↗
PubMed1993

[The occurrence of avian mycobacteriosis in wild birds during various epizootic conditions of tuberculosis in poultry].

The occurrence of tuberculosis in free-living birds was studied in relation to a certain epidemiological situation in a long-term study from 1966 to 1990. A total of 3210 birds were examined. Mycobacteria were isolated in five cases from free-living birds in the environment of six poultry rearing farms where tuberculosis was found in domestic fowl. At individual localities, the occurrence of mycobacteria was 3.5-50.0%. Generalized tuberculosis was found in one case in house sparrow (Passer domesticus). On the investigated poultry rearing farms, the distribution of tuberculosis infection in free-living birds was directly related to the distribution and stage of tuberculosis in poultry or to the achieved extent of eradication. On a poultry rearing farm where no mycobacteria were isolated from free-living birds, a successful eradication of tuberculosis by flock exchange was in progress. During the examination of free-living birds on three farms, mycobacteria were found at two localities where poultry infected with tuberculosis was kept either on the farm or in its immediate vicinity. On the third farm, where no mycobacteria were found in free-living birds, only sporadic reactors to tuberculin were found during survey in spatially separated flocks. No mycobacteria were isolated from birds examined on two farms in whose vicinity poultry was not reared at all. Similarly, bacteriological cultures were negative in a group of 298 birds examined during five years in the environment of a poultry enterprise farm free from tuberculosis. No mycobacteria were found in a large group of 2303 free-living birds taken in the wild except four rooks (Corvus frugilegus). However, this is a migratory species which is noted for its considerable longevity. It is thus more probable that these birds were infected outside the locality which the specimens were taken from. Out of the isolated strains of mycobacteria that were further examined by a biological experiment, 86.6% were pathogenic to domestic fowl, serotype M. avium 2. The results of these examinations suggest that the presence of tuberculosis-infected poultry as a major source of M. avium is necessary for the infection of free-living birds. The infectious agent apparently does not persist and spread within the flocks of free-living birds.

Animals↗
PubMed1998

A reassessment of the effect of body mass upon flight speed and predation risk in birds.

A number of theoretical studies have predicted that avian predation risk is mass dependent. Models of bird flight predict that increased mass will reduce flight velocity, making birds more vulnerable to predation. Empirical studies supporting this have demonstrated a significant relationship between mass and routine flight velocity (when birds are not alarmed). Studies investigating the effects of mass upon flight velocity when birds are alarmed, however, tend to show that the mass/velocity relationship is less marked. We found a real difference in the relationship between mass and flight velocity in zebra finches, Taeniopyga guttata, when comparing flights of alarmed and unalarmed birds. Despite the strong mass/routine velocity relationship already shown for zebra finches, mass tended to be a poor predictor of the flight velocity of alarmed birds within the natural weight range of the species. This difference appeared to be partly due to alarmed birds increasing their velocity more when heavy than when light, in comparison to their respective predicted routine flight velocities for their weights. As a result, mass/velocity regression slopes tended to be more shallow for alarmed birds. Consequently, increases in body mass within the natural weight range of a bird, may have less effect on the flight velocities of alarmed birds than they do on routine flight velocities. We therefore recommend caution in the use of weight as a predictor of predation risk in birds without examining its effects upon the flight velocity of alarmed birds. We suggest some explanations for the differences in the mass/velocity relationship between the flights of alarmed and unalarmed birds. Copyright 1998 The Association for the Study of Animal Behaviour.

Journal Article↗
PubMed2002

Variation within and between birds in corticosterone responses of great tits (Parus major).

The present study investigated inter- and intraindividual variation of the stress response (in terms of plasma levels of corticosterone) to handling in birds. Individual captive great tits (Parus major) were exposed to a standardised capture and handling protocol three times at about 2-week intervals. Mean plasma corticosterone levels were low (<5 ng/ml) when the birds were first sampled and increased in all birds 10 min after handling (mean levels on each sampling occasion 14 to 22 ng/ml). Levels in some birds then continued to increase, whereas in other birds levels remained relatively constant or had declined 30 min after handling began. Corticosterone responses were measured three times in each bird so that variation in plasma corticosterone levels could be defined. The area under the corticosterone response curve was defined as the integrated corticosterone response and was calculated for each response curve. Variation between birds was quantified by comparing mean values of corticosterone levels and integrated corticosterone responses between birds, then calculating a coefficient of variation for the mean of the individual bird means for each corticosterone parameter. Variation within birds was quantified by calculating the mean of the coefficients of variation for each bird for each corticosterone parameter. Variation in corticosterone levels in the first blood samples at 0 min (coefficient of variation (CV) 84.0%) was greater than variation in peak levels at 10 min (CV 35.1%) and in integrated corticosterone responses (CV 31.9%), indicating that corticosterone responses were more consistent between birds than were basal corticosterone levels. This study has demonstrated that corticosterone responses to a stressor tend to be repeatable in individual great tits, and has provided a method for quantifying variation in corticosterone responses for comparison with other birds in the future.

Corticosterone↗
PubMed1994

Egg yolk alpha-livetin (chicken serum albumin) is a cross-reactive allergen in the bird-egg syndrome.

Thirty-one patients with clinical history of egg allergy, bird allergy, or bird and egg allergy were investigated with the use of the immunoblot technique to compare IgE-binding components in bird feather and egg yolk and white extracts. Patients were classified into three groups according to clinical history, skin prick test results, and RAST results. Patients in group I were sensitized to bird feathers and egg yolk, patients in group II to egg white, and patients in group III to bird feather but not to eggs. Patients with bird-egg syndrome were mainly female adults, whereas egg white allergy was mainly observed in children without any obvious sex predisposition. IgE from patients with bird-egg syndrome recognized a 70 kd protein in egg yolk (chicken serum albumin = alpha-livetin) and some major allergens in bird feather extract (70, 95, and 200 kd). Preincubation of pooled sera from patients with bird-egg syndrome with budgerigar or hen feather extract and egg yolk extract, respectively, led to complete blocking of IgE binding to allergens in egg yolk and bird feather extract. On the other hand, IgE from patients with egg white allergy did not react with allergens in egg yolk and bird feather extract, despite strong IgE binding to egg white allergens. Patients in group III displayed no reactivity to bird feather or egg allergens. Our results demonstrate common epitopes of budgerigar and hen feather and egg yolk alpha-livetin. Therefore we assume that alpha-livetin (chicken serum albumin) leads to a cross-sensitization and consequently to the "bird-egg syndrome."

Adolescent↗
PubMed1999

Methods of detection of Chlamydia psittaci in domesticated and wild birds.

OBJECTIVE: To study the occurrence of Chlamydia psittaci in domesticated and wild birds and compare the sensitivity of molecular detection with cell culture isolation. DESIGN: Study of cell culture isolation and PCR detection of C psittaci in avian samples. PROCEDURE: Samples were obtained from 485 birds. Domesticated birds were selected at random from pet shops, private aviaries and zoos, while wild birds were captured locally, sampled, and immediately released. Swabs were collected from choanal slit, conjunctiva and cloaca of each bird and pooled. Samples were divided into equal portions for use in PCR dot-blot and cell culture detection. PCR and dot-blot detection was based on the ompB gene. RESULTS: Prevalence of infection varied markedly between flocks of captive birds. It was highest where there were frequent changes in the flock members or where there were many birds confined in small areas. C psittaci was not detected in wild birds or water birds. The sensitivity of cell culture compared to PCR dot-blot detection was 68%. All samples positive by cell culture were also positive by PCR. CONCLUSIONS: PCR-dot blot detection of C psittaci in birds appears to be more sensitive than cell culture isolation in this study. C psittaci infection of birds may occur in clinically normal captive birds.

Animals↗
PubMed2004

The roles of birds, lizards, and rodents as hosts for the western black-legged tick Ixodes pacificus.

We compared the infestation by ixodid ticks of lizards, rodents, and birds collected simultaneously within areas representing common habitat types in Mendocino County, CA. Lizards were infested only by Ixodes pacificus Cooley and Kohls, birds by I. pacificus and Haemaphysalis leporispalustris (Packard), and rodents by I. pacificus, I. spinipalpis Hadwen and Nuttall, I. woodi Bishopp, Dermacentor occidentalis Marx, and D. variabilis (Say). Infestation by I. pacificus larvae and nymphs of lizards (Sceloporus occidentalis Baird and Girard; Elgaria spp.) and western gray squirrels (Sciurus griseus Ord) (means of 9-35 larvae and 5-6 nymphs per animal) was several times greater than for Neotoma fuscipes Baird woodrats, Peromyscus spp. mice, and birds (means of 0.9-3.5 larvae and 0-0.3 nymphs). Overall, Borrelia-refractory lizards accounted for 84% of I. pacificus larvae and 91% of nymphs collected from animals in dense woodlands. Bird species frequently utilizing tick-questing substrates such as leaf litter (guild I birds) were more heavily infested by I. pacificus subadults (5.2 larvae and 1.0 nymphs per bird) than guild IV birds with minimal perceived contact with tick-questing substrates (0.08 larvae and 0.06 nymphs per bird). Notably, guild I birds carried similar larval loads and at least 20-fold higher nymphal loads relative to woodrats and mice. Only guild IV birds carried as few I. pacificus nymphs as did these rodents. The ratios of larvae to nymphs suggest that, relative to birds, lizards, and squirrels (infested by 1.3-6.0 larvae per nymph), nocturnally active ground-dwelling rodents such as woodrats and mice are underutilized by the nymphal stage (69 to >100 larvae per nymph). The western gray squirrel and guild I-II birds (e.g., the dark-eyed junco, Junco hyemalis [L.]) were the only potential reservoirs of Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt, and Brenner (the causative agent of Lyme disease in North America) that were frequently infested with both I. pacificus larvae and nymphs and commonly utilized dense woodland habitats.

Animals↗
PubMed1987

[Influenza virus epidemiology and ecology, with special reference to bird species associated with water. Literature review and observations].

Only a limited number of A-subtypes of influenza virus so far caused disease in human subjects, pigs and horses; this occurred in more or less defined areas which occasionally showed epidemic aggravations, becoming apparent as rapidly spreading epidemics or otherwise in even the form of pandemics. However this number of antigenic subtypes was found to be fairly constant and host-specific. Earlier studies were done in domesticated fowl and birds, though particularly in water birds in recent years, and numerous subtypes were detected, only a small number of these subtypes also being found to occur in man, pigs and horses. It became increasingly apparent that particularly mallards, but also other water birds play an extremely important role in the maintenance as well as in the distribution and circulation of these orthomyxoviruses in nature. These infections in water birds were not merely caused by a single subtype but occasionally by two or more antigenically different subtypes. This could be conducive to the appearance of recombinants as a result of genetic rearrangement in the cells lining the alimentary tracts of birds. Occasionally, subtypes observed in man were also found to occur in birds, which gave rise to the question of the extent to which birds are the origin or sources of infections of human epidemics caused by these subtypes. This also holds good for the subtypes in pigs. In addition to a number of oecological and ornithological considerations, reference was also made to systematic facts and routes along which further investigations on the presence of influenza viruses in the world of birds could be taken up, particular attention being paid to migratory birds. As birds of passage pass over and find their way into isolated areas as well as human population centres, these birds play a role which is yet unknown both in the distribution and in the overwintering of influenza viruses. Conditions in which wild and domesticated (water) birds, pigs, horses and man form a chain of close contact, and the areas in which new influenza viruses pathogenic for man are most likely to appear. Studies on the transgression of these barriers of species by subtypes of influenza virus still are entirely separate matter. The fact that a multidisciplinary approach is essential admits of no discussion.

Animals↗
PubMed2004

Functional variation among frugivorous birds: implications for rainforest seed dispersal in a fragmented subtropical landscape.

Seed dispersal plays a critical role in rainforest regeneration patterns, hence loss of avian seed dispersers in fragmented landscapes may disrupt forest regeneration dynamics. To predict whether or not a plant will be dispersed in fragmented forests, it is necessary to have information about frugivorous bird distribution and dietary composition. However, specific dietary information for frugivorous birds is often limited. In such cases, information on the seed-crushing behaviour, gape width and relative dietary dominance by fruit may be used to describe functional groups of bird species with respect to their potential to disperse similar seeds. We used this information to assess differences in the seed dispersal potential of frugivorous bird assemblages in a fragmented rainforest landscape of southeast Queensland, Australia. The relative abundance of frugivorous birds was surveyed in extensive, remnant and regrowth rainforest sites (16 replicates of each). Large-gaped birds with mixed diets and medium-gaped birds with fruit-dominated diets were usually less abundant in remnants and regrowth than in continuous forest. Small-gaped birds with mixed diets and birds with fruit as a minor dietary component were most abundant in regrowth. We recorded a similar number of seed-crushing birds and large-gaped birds with fruit-dominated diets across site types. Bird species that may have the greatest potential to disperse a large volume and wide variety of plants, including large-seeded plants, tended to be less abundant outside of extensive forests, although one species, the figbird Sphecotheres viridis, was much more abundant in these areas. The results suggest that the dispersal of certain plant taxa would be limited in this fragmented landscape, although the potential for the dispersal of large-seeded plants may remain, despite the loss of several large-gaped disperser species.

Animals↗
PubMed2006

Bird distributions relative to remotely sensed habitats in Great Britain: towards a framework for national modelling.

This paper develops a comprehensive and objective picture of bird distributions relative to habitats across Britain. Bird species presence/absence data from an extensive field survey and habitat data from the remotely sensed UK Land Cover Map 2000 were analysed in 36,920 tetrads (2 kmx2 km) across Britain (a 65% sample of Britain's c. 240,000 km2). Cluster analysis linked birds to generalised landscapes based on distinctive habitat assemblages. Maps of the clusters showed strong regional patterns associated with the habitat assemblages. Cluster centroid coordinates for each bird species and each habitat were combined across clusters to derive individualised bird-habitat preference indices and examine the importance of individual habitats for each bird species. Even rare species and scarce habitats showed successful linkages. Results were assessed against published accounts of bird-habitat relations. Objective corroboration strongly supported the associations. Relatively scarce coastal and wetland habitats proved particularly important for many birds. However, extensive arable farmland and woodland habitats were also favoured by many species, despite reported declines in bird numbers in these habitats. The fact that habitat-specialists do not or cannot move habitat is perhaps a reason for declining numbers where habitats have become unsuitable. This study showed that there are unifying principles determining bird-habitat relations which apply and can be quantified at the national scale, and which corroborate and complement the cumulative knowledge of many and varied surveys and ecological studies. This 'generality' suggests that we may be able, reliably and objectively, to integrate and scale up such disparate studies to the national scale, using this generalised framework. It also suggests the potential for a landscape ecology approach to bird-habitat analyses. Such developments will be important steps in building models to develop and test the sustainable management of landscapes for birds.

Animals↗
PubMed2001

An alternative method for delivering adrenocorticotropin hormone in birds.

In birds, intrajugular injection (i.j.) of exogenous adrenocorticotropin hormone (ACTH) has been used to challenge adrenocortical tissue when investigating various dynamics of the hypothalamic-pituitary-adrenal (HPA) axis. Although this method has been shown to deliver ACTH efficiently, i.j. injection can be difficult and potentially damaging to the bird, especially to young birds and small species. Intramuscular (i.m.) injection has been shown to be an alternative method for delivering ACTH to large birds; however, small songbirds have relatively less muscle mass in which to absorb i.m. injections and, in very small birds, even small needles may injure the delicate muscle tissue. Therefore, intraperitoneal (i.p.) administration of ACTH was investigated as a means of avoiding the potential problems associated with i.j. and i.m. injections when conducting adrenocortical pathway studies on small birds. Dark-eyed Juncos, Junco hyemalis, were first treated with dexamethasone to suppress the endogenous signal cascade for corticosterone release. Twelve hours later, birds were sampled for baseline corticosterone concentration and then immediately given an i.p. injection of either ACTH or physiological saline. A second blood sample was taken from all birds 30 min later to assess the effectiveness of i.p. ACTH administration on adrenocortical tissue. While saline-treated birds showed no significant increase in endogenous plasma corticosterone in response to the capture and handling protocol, ACTH-treated birds showed a significant increase in plasma corticosterone concentration, illustrating the effectiveness of the i.p. administration of exogenous ACTH. The adrenocortical response of ACTH-treated birds was similar in magnitude and rate of increase to that found in free-living, noninjected Juncos. Intraperitoneal injection of ACTH is thus a valid alternative to i.j. and i.m. injections when challenging adrenocortical tissue in small birds.

Adrenocorticotropic Hormone↗
PubMed1980

[Bird mortality and monitoring the environment (author's transl)].

Birds are useful parameters in studying toxicological contamination of the environment. Birds can be heard and seen, breeding results and feeding patterns being recorded on a rather extensive scale in the Netherlands. Since 1974, a working party was constituted to study normal and abnormal death of birds. This group consists of members of ornithological and veterinary institutes as well as local field workers, bird revalidation centres and bird preservation and protection groups. In 1979, approximately 2,000 birds were available for post-mortem and bacteriological, virological and toxicological studies. The cases of poisoning were classified into acute and chronic, accidental and crop-protecting effects. In the Laboratory of the Central Veterinary Institute, Poultry Department, the birds suspected of poisoning are screened by a biological-toxicological standard method using Lebistes and Daphnia. Pseudo-poisoning is caused in nature by Pasteurellosis, accidents, etc. Investigations are restricted by predation, the likelihood of finding of dead birds and retention of dead birds of prey for taxidermy. Acute poisoning in the Netherlands is mostly associated with protection of crops, nuisance caused by pigeons and other birds in gardens. Some cases of poisoning are due to quarrels between neighbours and people who poison game-birds out of revenge. Chronic poisoning is caused by metals such as lead pellets from cartridges. Chronic and acute poisoning continue to occur as a result of illegal use of prohibited insecticides.

Animals↗
PubMed2006

Scaling of body frontal area and body width in birds.

By analyzing a homogenous dataset we show, in contradiction to a previous study, that the scaling of body frontal area (S(b)) with body mass (m(b)) does not differ between passerine and nonpasserine birds. It is likely that comparison of data collected from live passerines with data collected from frozen nonpasserines had led to the incorrect conclusion that the scaling of S(b) varied between the taxa. We suggest that body dimensions collected from frozen specimens, or specimens stored in alcohol, are not applicable to live birds, and that both the current equations presented in the literature for predicting S(b) from m(b) may lead to inaccurate estimates. Using data from preserved specimens, we found that S(b) scales isometrically with m(b) (S(b) proportional, variant m(b) (0.66)), and therefore we found no evidence for larger birds being more streamlined than smaller birds. S(b) scales with negative allometry against wingspan (b), however, and b scales with positive allometry against m(b), so larger birds have smaller S(b) relative to b. In addition, it appears that dorsoventral flattening of the body is a general characteristic of bird's bodies but that it is more pronounced in larger birds, suggesting perhaps a function in terms of increased lift during forward flight. It appears that bird's bodies obey the surface-to-area geometric scaling law, but bird body shape may vary in relation to aerodynamic function. We suggest that a large-scale study, simultaneously measuring S(b) and m(b) in live passerines and nonpasserines, is required to improve the predictive power of S(b) upon m(b) scaling equations, which play a key role in the estimation of mechanical power consumption in flight in birds. Furthermore, the relations between bird body shape and axial skeleton dimensions, with reference to aerodynamic adaptation, warrant further investigation.

Animals↗
PubMed2007

Evaluation of the usefulness of bird feathers as a non-destructive biomonitoring tool for organic pollutants: a comparative and meta-analytical approach.

In this study, we investigated whether bird feathers can be used as a non-destructive biomonitor for organic pollutants. We analysed the outermost tail feathers of 8 terrestrial and aquatic bird species from Belgium (8 species, n=108) for polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and organochlorine pesticides (OCPs). Every compound class could be quantified in one single tail feather of the birds under study (sum PCBs ranging from 5.5 to 510 ng/g feather, sum PBDEs from 0.33 to 53 ng/g feather, sum DDTs from 1.5 to 730 ng/g feather), except for PBDEs in feathers of the common moorhen (Gallinula chloropus). Further, we calculated Pearson correlations between concentrations of organic pollutants in feathers and concentrations in corresponding muscle or liver tissue from the birds. Correlations were found significant in half of the cases of the terrestrial species, but were found not significant for the aquatic species, with the exception of a significant correlation of sum PCBs in the common moorhen. Only for the common buzzard (Buteo buteo) (n=43) all correlations were found significant (0.32<r<0.77). In order to cope for low statistical power, we performed a meta-analysis on all bird species together. This led to significant correlations between levels in feathers and corresponding levels in muscle or liver for all terrestrial birds (p<0.05 in all cases, effect size 0.59 (p,p'-DDE) to 0.71 (Sigma PCB) for levels in feather and muscle). When correlations were recalculated excluding the birds that had died due to starvation, correlation coefficients for the terrestrial birds were found even higher (effect size up to 0.83 (Sigma PCB)). These results have important implications for non-destructive and retrospective biomonitoring. Although our results suggest that exact concentrations in the body cannot be predicted using feathers, bird feathers can give a good estimate of contamination levels in a population and as such are a potential non-destructive biomonitoring tool for organic pollutants. Outermost tail feathers and muscle tissue were also examined for nitrogen (delta15N) and carbon (delta13C) stable isotope content in the different bird species. However, delta15N/delta13C signatures in feather or muscle were not significantly correlated with the corresponding levels of organic pollutants in these tissues. Various confounding factors (such as habitat, condition, age, sex) may have masked a relationship between delta15N values and organic pollutant levels in the birds under study.

Animals↗
PubMed1994

Diagnosis of polyomavirus-induced hepatic necrosis in psittacine birds using DNA probes.

Liver sections from 32 psittacine birds with multifocal to coalescing hepatocellular necrosis were examined to determine the cause of disease. Avian polyomavirus (APV) infection (19 of 32 birds), bacterial hepatitis (5 of 32 birds), and chlamydiosis (3 of 32 birds) were major causes of hepatic disease. The presence of APV inclusions or nucleic acid was demonstrated using hematoxylin and eosin (HE) staining, DNA in situ hybridization, and DNA amplification with Southern blotting. Amphophilic intranuclear inclusions, suggestive of APV infection, were observed in HE-stained liver sections from 5 of 32 birds. Hepatocellular karyomegaly was present in liver tissues from 10 birds (5 birds with typical APV inclusions and 5 birds without discernable inclusions). DNA in situ hybridization recognized intranuclear APV nucleic acid in liver sections of 18 of 32 birds. DNA amplification with Southern or dot blots also identified APV nucleic acid in processed, paraffin-embedded livers of 18 of 32 birds. This study demonstrates that acute APV infection is a frequent cause of multifocal to coalescing hepatocellular necrosis in psittacine birds. Furthermore, APV infection is best diagnosed using DNA probes, especially when typical intranuclear inclusions are not observed microscopically.

Animals↗
PubMed2001

Birds and their ticks in northwestern California: minimal contribution to Borrelia burgdorferi enzootiology.

Birds and their attendant ticks were surveyed for infection with the Lyme disease spirochete Borrelia burgdorferi, in chaparral and woodland-grass habitats in northwestern California from March to July, 1998 to 1999. In total, 234 birds were captured and recaptured (15%); nearly 2.5 times more birds were captured in chaparral than in woodland-grass. Overall, 34 species representing 15 families were collected during this study; of these, 24 species were caught in chaparral, 19 in woodland-grass, and 9 in both vegetational types. The most frequently captured birds were sage sparrows (Amphispiza belli) in chaparral, and American robins (Turdus migratorius) and oak titmice (Baelophus inornatus) in woodland-grass. Birds hosted 35 Ixodes pacificus (15 larvae, 20 nymphs) and 9 Haemaphysalis leporispalustris (3 larvae, 5 nymphs, 1 adult) ticks, of which 32 were removed from chaparral birds and 12 from woodland birds. The prevalence of tick infestation was 13% (21/167) in chaparral and 5% (3/67) in woodland-grass, but the relative and mean tick intensities of 0.19 and 1.5 for chaparral birds, and 0.18 and 4.0 for woodland birds, respectively, did not differ significantly by habitat. Spirochetes were not detected in either bird-blood or tick-tissue samples when tested by culture, immunofluorescence, or Giemsa-staining. In contrast, over 90% (86/94) of western fence lizards (Sceloporus occidentalis) collected in June or July were infested with an average of 6.9 and 8.9 immature I. pacificus in chaparral and woodland-grass, respectively. We conclude that birds contribute little to the enzootiology of B. burgdorferi in chaparral and woodland-grass habitats in northwestern California because of their limited parasitism by tick vectors and lack of detectable spirochetemias.

Animals↗
PubMed1997

Ticks, Lyme disease spirochetes, trypanosomes, and antibody to encephalitis viruses in wild birds from coastal Georgia and South Carolina.

Ticks and blood samples were collected from wild birds mist-netted on St. Catherine's Island, Georgia, and at the Wedge Plantation in coastal South Carolina in 1994 and 1995. Immature stages of 5 species of ixodid ticks were recovered from 10 of 148 (7%) birds belonging to 6 species in Georgia, whereas 6 ixodid species were recovered from 45 of 259 (17%) birds representing 10 avian species in South Carolina. Borrelia burgdorferi sensu lato was isolated from 27 of 120 (23%) screened ticks (Ixodes scapularis and Ixodes minor) recovered from South Carolina birds, but from none of 16 screened ticks removed from Georgia birds. This spirochete was also isolated from 1 of 97 (1%) birds in South Carolina. In 1995, neither eastern equine encephalitis (EEE) virus nor St. Louis encephalitis (SLE) virus was isolated from any of 218 bird sera screened, but serum neutralizing antibodies were found to EEE virus in 4 of 121 (3%) sera and to SLE virus in 2 of 121 (2%) sera from South Carolina. No antibody to either virus was detected in 51 avian sera screened from Georgia. Trypanosomes (probably Trypanosoma avium) were isolated from 1 of 51 (2%) birds from Georgia and from 13 of 97 (13%) birds from South Carolina. Our data suggest that some wild birds may be reservoir hosts for the Lyme disease spirochete and for encephalitis viruses in coastal Georgia and South Carolina and that migrating birds can disperse immature ticks infected with B. burgdorferi.

Animals↗
PubMed1998

Results of postmortem examination of psittacine birds with cardiac disease: 26 cases (1991-1995).

OBJECTIVE: To characterize prevalence and type of cardiac disease evident in psittacine birds during postmortem examination. DESIGN: Retrospective study. ANIMALS: 26 psittacine birds with gross and histologic evidence of cardiac disease. PROCEDURE: Records of postmortem examinations of psittacine birds necropsied during a 4-year period were reviewed. Data on gross and histologic evidence of cardiac disease were analyzed. Birds identified included those in which congestive heart failure (CHF) was considered the primary cause of death and those in which substantial cardiac disease was evident, despite a lack of postmortem findings supportive of CHF. RESULTS: Of 269 psittacine birds necropsied, 26 (9.7%) had evidence of cardiac disease. In 15 (58%) birds with cardiac disease, changes consistent with CHF were evident and were sufficiently severe as to be considered the cause of death. The remaining 11 birds had cardiac lesions secondary to other systemic diseases; cardiac lesions were considered to be an incidental finding in these birds, and CHF was not evident. Of the 15 birds with CHF, 10 had evidence of right ventricular or biventricular failure, whereas only 5 had evidence of left ventricular failure. CLINICAL IMPLICATIONS: Prevalence of cardiac disease in the psittacine birds reported here was similar to that seen clinically in other companion animals. The high incidence of right ventricular or biventricular heart failure in psittacine birds was similar to that for poultry in which lesions of right-sided heart failure predominate.

Animals↗