Bird Leg Skin Lesions and Urbanization in a Neotropical Savanna City.

Urban sprawl threatens biodiversity and is responsible for significant changes in the species that live in these environments. Given the high cost of comprehensive surveillance, monitoring disease indirectly, such as detecting skin lesions in birds, may help us better understand the prevalence of diseases affecting wild populations. We assessed the frequency of leg skin lesions, as a proxy of disease presence, in 1,565 individuals of 25 species, along the urban matrix of a large Neotropical city, Brasília, Federal District, Brazil. We tested the hypothesis that there is an increase in the frequency of skin lesions in birds due to urban intensification. We observed an increasing trend in some bird species between the frequency of occurrence of lesions and the intensity of urbanization. Species with a higher number of captures had an increase in the percentage of lesions, indicating that the occurrence of lesions may be linked to higher population density or that detection of the effect occurs only when sample sizes are high and controlled among urbanization categories. Our study highlights how the intensity of urbanization may increase the risk of disease transmission for these species. Unfortunately, studies on this topic are scarce in Neotropical regions, despite the region's high biodiversity and urban expansion.

First Isolation and Molecular Characterization of Umatilla Virus (Sedoreoviridae, Orbivirus) in Brazil.

In this study, we provide a genomic description of the first isolation of the Umattila virus (UMAV) in Brazil. The virus was obtained from the blood of a bird (Turdus fumigatus) and isolated in a C6/36 cell culture. The viral genome contains ten segments, and its organization is characteristic of viruses of the genus Orbivirus (family Sedoreoviridae). The coding region of each segment was sequenced, demonstrating the nucleotide identity with UMAV. The phylogenetic inference results were in line with these findings and demonstrated the formation of two distinct monophyletic clades containing strains isolated around the world, where our isolate, belonging to the same clade as the prototype strain, was allocated to a different subclade, highlighting the genetic divergence between them. This work reports the first isolation of UMAV in Brazil, and due to the scarcity of information on this viral agent in the scientific literature, it is essential to carry out further studies to better understand its epidemiology, dispersion, and, in particular, its interactions with vertebrate hosts, vectors, and the environment.

Coccidia of Guinea fowls: Validity of recorded Eimeria spp. (Apicomplexa: Eimeriidae) and first molecular identification of Eimeria grenieri Yvoré & Aycardi, 1967.

Guinea fowls, Numida meleagris (L., 1758), are galliform birds native to sub-Saharan Africa, but introduced in several countries around the world for domestic breeding and/or animal production. This species is considered more resistant to disease by Eimeria spp. than other domestic galliform birds. Here we review the Eimeria spp. known to infect species of Numididae and provide the first molecular identification of an Eimeria sp. from Guinea fowls. There are currently 3 named eimerians from Guinea fowls; Eimeria numidae Pellerdy, 1962; Eimeria grenieri Yvoré and Aycardi, 1967; and Eimeria gorakhpuri Bhatia & Pande, 1967. We reviewed each of these species descriptions and documented their taxonomic shortcomings. From that, we suggest that E. gorakhpuri is a junior synonym of E. numidae. In conclusion, we have morphologically redescribed in detail E. grenieri from N. meleagris from Rio de Janeiro and provided molecular supplementation through sequencing of three non-overlapping loci in cox1 and cox3 genes and fragments of small and large subunit mitochondrial rDNA.

Isospora pichororei n. sp. (Chromista: Apicomplexa: Eimeriidae) from rufous-capped spinetails Synallaxis ruficapilla Vieillot, 1819 (Passeriformes: Furnariidae: Synallaxiinae) in South America.

Spinetails are a suboscine passerines of the genus Synallaxis Vieillot, 1818 which have great interest for ornithology, given the wide diversity of 37 species that are distributed throughout the Neotropical region. Despite this wide diversity and distribution, Synallaxis spp. have never been recorded as hosts of coccidian parasites. In this context, the current study describes a new species of Isospora Schneider, 1881 from rufous-capped spinetails Synallaxis ruficapilla Vieillot, 1819 captured in the Itatiaia National Park, which is a federal conservation unit in Southeastern Brazil. The oocysts of Isospora pichororei Genovez-Oliveira & Berto n. sp. are subspheroidal to ovoidal, measuring on average 25 by 21 µm. Micropyle is present, but discrete. Oocyst residuum absent, but one or two polar granules are present. Sporocysts are ellipsoidal with slightly pointed posterior end, measuring on average 17 by 10 µm. Stieda and sub-Stieda bodies are present. Sporocyst residuum is clustered among the vermiform sporozoites, which have striations, refractile bodies and nucleus. This morphology was different from the other Isospora spp. recorded in the host family Furnariidae. Molecular identification was targeted by the amplification and sequencing of a locus of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene. This sequence had the highest similarity of 99.5% with a sequence deposited for Isospora oliveirai Ortúzar-Ferreira & Berto, 2020, which is a coccidian species that parasitizes suboscine tityrids Schiffornis virescens (Lafresnaye, 1838), also in the Itatiaia National Park. Phylogenetic analysis grouped some species in subclades, including I. pichororei with I. oliveirai; however, it was inconclusive in an expectation of parasite-host coevolution. Finally, I. pichororei is established as new to science, being the first description from Synallaxinae and the third description from Furnariidae. Furthermore, this is the first Isospora sp. from the host family Furnariidae to have a molecular supplementation by sequencing a locus of the cox1 gene of the mitochondrial genome.

Prevalence and composition of haemosporidians in an avian community from a World Heritage area: Associations with host foraging strata and forest regeneration.

Forest regeneration is becoming a powerful tool to combat land conversion which covers 30 % of the Neotropical territory. However, little is known about the effect of forest regeneration on vector-borne diseases. Here, we describe the haemosporidian lineage composition across a successional gradient within an Atlantic Forest bird community. We test whether forest successional stages, in addition to host life history traits affect haemosporidian infection probability. We sampled birds at 16 sampling units with different successional stages between 2017 and 2018 within a forest remnant located in Antonina, Paraná, Brazil. We captured bird individuals using mist-nets, identified them to the species level, and collected blood samples to detect and identify Plasmodium and Haemoproteus lineages based on molecular analysis. We used a Bayesian phylogenetic linear model with a Bernoulli distribution to test whether the haemosporidian infection probability is affected by nest type, foraging stratum, and forest successional stage. We captured 322 bird individuals belonging to 52 species and 21 families. We found 31 parasite lineages and an overall haemosporidian prevalence of 23.9 %, with most infections being caused by Plasmodium (21.7 % of prevalence). The Plasmodium probability of infection was associated with forest successional stage and bird foraging stratum. Birds from the secondary forest in an intermediate stage of succession are more likely to be infected by the parasites than birds from the primary forests (ß = 1.21, 95 % CI = 0.11 - 2.43), birds from upper strata exhibit a lower probability of infection than birds from lower foraging strata (ß = -1.81, 95 % CI = -3.80 - -0.08). Nest type did not affect the Plasmodium probability of infection. Our results highlight the relevance of forest succession on haemosporidian infection dynamics, which is particularly relevant in a world where natural regeneration is the main tool used in forest restoration.

Morphological and molecular identification of Sarcocystis falcatula from the emerald toucanet (Aulacorhynchus albivitta) in Colombia.

Sarcocystis spp. are cyst-forming coccidia characterized by a two-host predator-prey life cycle. Sarcocysts are formed in muscles or nervous system of the intermediate host, while sporocysts develop in the small intestine of the definitive host. The intermediate hosts of Sarcocystis falcatula are wild birds. Colombia is one of the countries with the greatest biodiversity of birds, however, there are few studies related to this parasite in wild birds. This study presents the morphological and molecular detection of Sarcocystis falcatula collected from the emerald toucanet (Aulacorhynchus albivitta), a wild bird species endemic to South America. Pectoral muscle samples were obtained, and microscopic and molecular detection was performed by light microscopy, transmission electron microscopy, and amplifying of the first internal transcribed spacer (ITS-1) and surface antigen-encoding genes (SAGs). Sarcocystis measured an average of 161  × 42 µm, with a cyst wall ∼0.4 µm thick. Ultrastructurally, the sarcocyst wall type 11b-like consisted of numerous villar protrusions of 850 nm wide on average. The ITS-1 sequence showed 97.0-99.7% identity to S. falcatula previously described from birds in the United States and Brazil, respectively. Concatenated phylogenetic analysis based on SAG2, SAG3 and SAG4 confirmed that the new isolate is grouped with other sequences of Sarcocystis from South America, but divergent from those isolates obtained in North America. The results of this study demonstrate for the first time the presence of S. falcatula in a wild bird from Colombia.

Detection of Mycoplasma spp. in free-living seabirds.

This study aimed to investigate the presence of Mycoplasma spp. and identify the species of mycoplasma isolates obtained from seabirds found on Brazilian coastal beaches. Tracheal and cloacal swab samples were collected from 50 seabirds rescued by three conservation and marine animal rehabilitation centers located in Brazil. The tracheal and cloacal samples were subjected to mycoplasma culture and the isolates were identified through PCR. A "Mollicutes-specific" 16S rRNA PCR reaction was employed for triage. Four species-specific PCR reactions were used to detect Mycoplasma gallisepticum, Mycoplasma synoviae, Mycoplasma meleagridis, or M. gallinarum. The Mollicutes positive and species negative samples were submitted do 16S rRNA sequencing. Eighteen (36%) of 50 seabirds tested positive for mycoplasma by culture. In the PCR for the genus, 28 (56%) of 50 seabirds were positive for Mycoplasma spp., with 13 (26%) detected in the trachea, one (2%) in the cloaca, and 14 (28%) in both sites. In the species-specific PCR, M. gallisepticum was detected in 17.8%, and M. meleagridis in 17.8%. Both species were detected in 14.3%. Of the isolates not characterized at species level, we obtained ten sequences and they were divided into three clusters. The first cluster was closely related to M. meleagridis, the second to M. synoviae, and the third grouped M. tully, M. gallisepticum, and M. imitans. Four and five of nine species of seabirds studied had mycoplasma detected by culture or PCR, respectively. Mycoplasmas were found in the majority of the animals studied, with the highest prevalence proportionally found in Sula leucogaster, and the lowest in Fregata magnificens. The phylogenetic analysis identified Mycoplasma spp. adapted to aquatic birds.

Herpesviruses in migrating procellariforms, northeastern Brazil.

Seabirds are one of the most threatened avian groups. Viruses, including herpesvirus, represent considerable threats to marine avifauna. Herein, our goal was to survey herpesvirus in Procellariiformes that stranded in Brazil between June and July 2021. We analyzed 12 Cory's shearwaters (Calonectris borealis), two Great Shearwaters (Ardenna gravis, syn. Puffinus gravis) and one Yellow-nosed Albatross (Thalassarche chlororynchos) found in an unusual mortality event in Bahía state, northeastern Brazil. After necropsy, selected tissue samples were tested for herpesvirus using a broad-range nested PCR. Overall, 20% (3/15) of the birds were herpesvirus-positive, i.e., two Cory's Shearwaters and one Great Shearwater. One alphaherpesvirus sequence type was identified in each shearwater species, classified into the genus Mardivirus. This study describes two likely novel herpesviruses in shearwaters, contributing to the currently very scarce data regarding infectious agents in Procellariiformes. Further studies are necessary to evaluate the presence and characteristics of herpesvirus in Procellariiformes, and the presence (or not) of related disease in order to understand the epidemiology of this infectious agent and eventually contribute to the conservation of this endangered seabird group.

Prevalence and parasite burden of oocysts in captive and free-living saffron finches, Sicalis flaveola.

The saffron finch, Sicalis flaveola, a passerine bird, can be found in nearly all Brazilian territory and is also raised in captivity. The objective of this work was to determine the prevalence and load of oocysts in captive saffron finches in the municipality of Campos dos Goytacazes, state of Rio de Janeiro and in free-living saffron finches in the municipality of Eugenopolis, state of Minas Gerais. In this analysis, 30 captive and 30 wild birds were assessed. Feces eliminated in a 24-hour period were collected and weighed to determine the number of oocysts per gram of feces (OoPG). Statistical analyses were performed using Microsoft Excel and GraphPad Prism Software. All birds in the present study were positive for one or more species of coccidia. Captive birds had a mean total oocyst count higher than that of wild birds. No significant differences in OoPG counts were observed when comparing males and females or captive and wild birds. We can conclude that due to the fact that birds both eat and defecate in their cages, it is essential to keep them as clean as possible, since captive birds have a higher prevalence of coccidia.

Molecular diversity and polyparasitism of avian trypanosomes in the Brazilian Atlantic Rainforest.

The current study proposes to investigate the diversity and phylogeny of trypanosomes parasitizing wild birds from the Brazilian Atlantic Forest. Cytological examination was carried out by light microscopy of blood smears and positive birds were selected for amplification of the 18S rDNA sequence through PCR. The resulting amplicons were subjected to purification, cloning, and sequencing analysis. Phylogenetic reconstruction was conducted, including all avian trypanosomes representative's lineages. A total of ten bird samples from species of Turdus flavipes (N=1/12), T. albicollis (N=1/8), Tachyphonus coronatus (N=6/121), Thamnophilus caerulescens (N=1/22) and Synallaxis spixi (N=1/8) were positive for Trypanosoma spp. In the six specimens of T. coronatus, five distinct lineages of Trypanosoma spp. 18S-rRNA were observed in ninety sequences obtained, and using the strategy of cloning independent PCR, it was possible to observe that two of them were related to T. avium (JB01/JB02), and three were closed related to T. bennetti (JB03/ JB04/JB05). Addionaly, all fifteen sequences obtained from T. caerulescens/ S. spixi/T. flavipes/T. albicollis were identical. The present research is the first study to access molecular diversity and polyparasitism by avian trypanosomes in Brazil. The current research exhibits the wide genetic variability in avian trypanosomes and its non-specific relationship with its avian hosts.

Environmental and ecological factors affecting tick infestation in wild birds of the Americas.

The Americas hold the greatest bird diversity worldwide. Likewise, ectoparasite diversity is remarkable, including ticks of the Argasidae and Ixodidae families - commonly associated with birds. Considering that ticks have potential health implications for humans, animals, and ecosystems, we conducted a systematic review to evaluate the effects of bioclimatic, geographic variables, and bird species richness on tick infestation on wild birds across the Americas. We identified 72 articles that met our inclusion criteria and provided data on tick prevalence in wild birds. Using Generalized Additive Models, we assessed the effect of environmental factors, such as habitat type, climatic conditions, bird species richness, and geographic location, on tick infestation. Our findings show that most bird infestation case studies involved immature ticks, such as larvae or nymphs, while adult ticks represented only 13% of case studies. We found birds infested by ticks of the genera Amblyomma (68%), Ixodes (22%), Haemaphysalis (5%), Dermacentor (1%), and Rhipicephalus (0.8%) in twelve countries across the Americas. Our findings revealed that temperature variation and bird species richness were negatively associated with tick infestation, which also varied with geographic location, increasing in mid-latitudes but declining in extreme latitudes. Our results highlight the importance of understanding how environmental and bird community factors influence tick infestation in wild birds across the Americas and the dynamics of tick-borne diseases and their impact on biodiversity.

Avian haemosporidians of the genera Plasmodium and Haemoproteus from resident and Neotropical migrant birds in Colombia.

Avian haemosporidians of the genera Plasmodium and Haemoproteus are a group of widely distributed blood parasites that can negatively affect the fitness of their hosts. Colombia contains the greatest diversity of birds on the planet, but knowledge about the associations between haemosporidian and its avifauna is scarce and fragmented. We collected blood samples from 255 birds (203 residents and 52 neotropical migrants) belonging to 27 families and 108 species. The study was conducted in six localities in the inter-Andean valleys of the Cauca and Magdalena rivers. Parasites of the genera Plasmodium and Haemoproteus were identified in the samples by morphological and molecular analysis of a fragment of the mitochondrial gene cyt b. Among the samples, 9.3% (n = 24) were positive for Plasmodium or Haemoproteus. Co-infection with Plasmodium and Haemoproteus was found in Red-eyed Vireo. Seventeen haemosporidian lineages were identified, five of which were reported for the first time in resident birds (Common Ground Dove, Checker-throated Stipplethroat, Tropical Kingbird, Pale-breasted Thrush, and Ruddy-breasted Seedeater) and one in the Summer Tanager (neotropical migrant). The research results confirm the wide diversity of haemosporidian present in tropical lowlands and the possible role of neotropical migratory birds in dissemination on haemosporidian along their migratory routes.

Systematics and life cycles of four avian schistosomatids from Southern Cone of South America.

Relative to the numerous studies focused on mammalian schistosomes, fewer include avian schistosomatids particularly in the southern hemisphere. This is changing and current research emerging from the Neotropics shows a remarkable diversity of endemic taxa. To contribute to this effort, nine ducks (Spatula cyanoptera, S.versicolor, Netta peposaca), 12 swans (Cygnus melancoryphus) and 1,400 Physa spp. snails from Chile and Argentina were collected for adults and larval schistosomatids, respectively. Isolated schistosomatids were preserved for morphological and molecular analyses (28S and COI genes). Four different schistosomatid taxa were retrieved from birds: Trichobilharzia sp. in N. peposaca and S. cyanoptera that formed a clade; S.cyanoptera and S. versicolor hosted Trichobilharzia querquedulae; Cygnus melancoryphus hosted the nasal schistosomatid, Nasusbilharzia melancorhypha; and one visceral, Schistosomatidae gen. sp., which formed a clade with furcocercariae from Argentina and Chile from previous work. Of the physid snails, only one from Argentina had schistosomatid furcocercariae that based on molecular analyses grouped with T. querquedulae. This study represents the first description of adult schistosomatids from Chile as well as the elucidation of the life cycles of N.melancorhypha and T. querquedulae in Chile and Neotropics, respectively. Without well-preserved adults, the putative new genus Schistosomatidae gen. sp. could not be described, but its life cycle involves Chilina spp. and C. melancoryphus. Scanning electron microscopy of T. querquedulae revealed additional, undescribed morphological traits, highlighting its diagnostic importance. Authors stress the need for additional surveys of avian schistosomatids from the Neotropics to better understand their evolutionary history.

PARROT BORNAVIRUSES IN PSITTACINES KEPT IN CAPTIVITY IN THE STATE OF SANTA CATARINA, BRAZIL.

Parrot bornaviruses are responsible for proventricular dilatation disease (PDD) in psittacines. This study aimed to determine the occurrence and factors associated with Parrot bornaviruses infection in psittacines kept in captivity in a state in the southern region of Brazil. A cross-sectional study was carried out with 192 birds from two facilities (A and B) in 2019, using choanal, esophageal, and cloacal swabs and feathers, totaling 768 samples subjected to reverse-transcription polymerase chain reaction (RT-PCR), for the matrix (M) protein gene with a final product of 350 base pairs (bp). Genetic sequencing of three positive samples was performed by the Sanger method. In the study, the overall virus occurrence was 35.9% (69/192), with 40.4% (42/104) in Facility A and 30.7% (27/88) in Facility B. Sequencing analysis of the samples revealed the presence of Parrot bornavirus 2 (PaBV-2) in both facilities. Swab samples from the choanal (40/69), esophageal (30/69), cloacal (35/69), and feather (15/69) tested positive, facilitating the molecular diagnosis of Parrot bornaviruses. The results indicated that there is no single ideal sample type for antemortem molecular diagnosis of this virus. Simultaneously testing all four samples at the same time point yielded more diagnoses than testing any single sample among the four. Most of the 29 sampled psittacine species were native, and 46.9% of the birds (90/192) consisted of endangered species. Among the psittacines that tested positive, 88.4% (61/69) were clinically healthy, and 8.7% (6/69) exhibited clinical or behavioral signs, including behavioral changes, alterations in feathering, and changes in body score at the time of collection. This study showcases the application of minimally invasive sampling for diagnosing Parrot bornaviruses, enabling sample collection when the birds are restrained for clinical evaluation. This approach facilitates a prompt and effective antemortem diagnosis, thereby serving as an efficient screening method for parrots kept in captivity.

First Record of the Genus Trochiliphagus Carriker 1960 (Amblycera: Ricinidae) Infesting a Hummingbird from Brazil.

Four genera and at least fifty species of chewing lice have been recorded infesting hummingbirds (Trochilidae). Here, we record for the first time, the genus Trochiliphagus in Brazil, as well as, a new host record for Trochiliphagus mellivorus Carriker, the fork-tailed woodnymph, Thalurania furcata.

Correlates of Co-Infection with Coccidiosis and Avian Malaria in House Finches (Haemorhous mexicanus).

Pathogens have traditionally been studied in isolation within host systems; yet in natural settings they frequently coexist. This raises questions about the dynamics of co-infections and how host life-history traits might predict co-infection versus single infection. To address these questions, we investigated the presence of two parasites, a gut parasite (Isospora coccidians) and a blood parasite (Plasmodium spp.), in House Finches (Haemorhous mexicanus), a common passerine bird in North America. We then correlated these parasitic infections with various health and condition metrics, including hematological parameters, plasma carotenoids, lipid-soluble vitamins, blood glucose concentration, body condition, and prior disease history. Our study, based on 48 birds captured in Tempe, Arizona, US, in October 2021, revealed that co-infected birds exhibited elevated circulating lutein levels and a higher heterophil:lymphocyte ratio (H/L ratio) compared to those solely infected with coccidia Isospora spp. This suggests that co-infected birds experience heightened stress and may use lutein to bolster immunity against both pathogens, and that there are potentially toxic effects of lutein in co-infected birds compared to those infected solely with coccidia Isospora sp. Our findings underscore the synergistic impact of coparasitism, emphasizing the need for more co-infection studies to enhance our understanding of disease dynamics in nature, as well as its implications for wildlife health and conservation efforts.

Pathological lesions associated with avian schistosomes (Digenea: Schistosomatidae) in the freshwater snail Chilina dombeiana (Gastropoda: Chilinidae) from Southern Chile.

Avian schistosomes inhabit the blood stream of domestic and wild birds with aquatic snails as their intermediate hosts. In the Neotropics there is an emerging effort to describe species from these hosts, including Chile, although the knowledge about their pathological consequences is mostly understudied. This study aimed to describe the pathological changes associated with the parasitism of a native schistosomatid restricted to the Southern Cone of Neotropics. To achieve this, a total of 401 Chilina dombeiana snails (Chilinidae) were collected in two locations from Southern Chile. All of them were disposed to cercarial release procedure for three consecutive days. Furcocercariae released were stained and characterized by microscopic evaluation. Then, all snails were dissected under stereomicroscope and preserved in 10 % buffered formalin until histopathological analysis was performed. Eight out 401 (P = 2 %) snails were found parasitized with avian schistosomes. The released furcocercariae were identified as Schistosomatidae gen. sp. Lineage II which was previously reported in the same host. The main pathological change was an atrophy of ovotestes and an absence or mild infiltration of hemocytes in the surrounding tissues. Besides, a co-infection with echinostomes was found which was associated with a moderate hemocyte infiltration, granuloma-like lesion, and a reduced presence of schistosome' sporocysts. The latter would suggest an antagonistic interaction between these two digeneans, as has been proposed in the Echinostoma spp.-Schistosoma mansoni model. Despite the above, the release of furcocercariae was present but reduced, in contrast with the non-release of echinocercariae. This interaction requires further attention. This study represents the first attempt to characterize the pathological consequences of parasitism by a native, yet undescribed, avian schistosome in an endemic snail. Future studies should consider experimental infections to understand the dynamics of single infections in other Chilina species, including inter- and intra-specific parasitism as previous studies have found, including this study.

Lymphomas in seabirds: case reports in a black skimmer (Rynchops niger) and a brown booby (Sula leucogaster).

A black skimmer (Rynchops niger) and a brown booby (Sula leucogaster) were rescued and gross, histopathological, immunohistochemical and polymerase chain reaction evaluations were conducted to investigate the cause of death. There were neoplastic infiltrations of CD3+ PAX5- lymphocytes in the black skimmer and CD3- PAX5+ lymphocytes in the brown booby. Molecular assays for viral agents were negative in both cases. This is the first report of disseminated lymphoma as the cause of stranding and death in these species in Brazil.

Antimicrobial Sensitivity Profile in Psittacine Birds at an Avian Teaching Hospital: A Retrospective Study, 2015-2022.

Veterinary hospitals house patient populations with diverse infectious statuses, microbiota, and histories of prior antibiotic therapy. Choanal swabs are commonly used for assessing the upper respiratory tract of birds for bacterial disease, with the samples submitted for cytologic testing and/or culture and antimicrobial sensitivity testing. The aim of this retrospective study was to identify and quantify bacteria isolated from choanal swabs collected from psittacine patients at a veterinary teaching hospital in Mexico City, Mexico. Data regarding bacterial isolates from choanal swabs were obtained from the medical records of companion psittacines suspected of upper respiratory bacterial disease that presented between November 2015 and December 2022. A total of 47.8% (175 of 366) of the bacterial isolates were from specimens obtained from red-lored Amazons (Amazona autumnalis). Gram-negative bacteria predominated, with 27 different genera identified. Klebsiella, Staphylococcus, and Escherichia were the most frequently isolated genera. A total of 90.4% (331 of 366) of the isolates were resistant to at least 1 antibiotic tested in the sensitivity panel, and a single Klebsiella isolate was resistant to 13 different antibiotics. Gentamicin had a high percentage of efficacy (79.5%; 182 of 229) against the bacterial isolates, whereas isolates tested against sulfonamide-trimethoprim (46.7%, 98 of 210), streptomycin (43.8%; 88 of 201), and clindamycin (12.9%; 15 of 116) had susceptibilities <50%. This is the first study to report common bacterial isolates and their antimicrobial susceptibility patterns from choanal swab samples collected from companion psittacines suspected of upper respiratory disease in Mexico. Clinicians can use the information presented in this study as a guide for therapeutic decision-making when managing upper respiratory bacterial infections in companion psittacine patients.

Higher body condition with infection by Haemoproteus parasites in Bananaquits (Coereba flaveola).

Parasite transmission is a heterogenous process in host-parasite interactions. This heterogeneity is particularly apparent in vector-borne parasite transmission where the vector adds an additional level of complexity. Haemosporidian parasites, a widespread protist, cause a malaria-like disease in birds globally, but we still have much to learn about the consequences of infection to hosts' health. In the Caribbean, where malarial parasites are endemic, studying host-parasites interactions may give us important insights about energetic trade-offs involved in malarial parasites infections in birds. In this study, we tested the consequences of Haemoproteus infection on the Bananaquit, a resident species of Puerto Rico. We also tested for potential sources of individual heterogeneity in the consequences of infection such as host age and sex. To quantify the consequences of infection to hosts' health we compared three complementary body condition indices between infected and uninfected individuals. Our results showed that Bananaquits infected by Haemoproteus had higher body condition than uninfected individuals. This result was consistent among the three body condition indices. Still, we found no clear evidence that this effect was mediated by host age or sex. We discuss a set of non-mutually exclusive hypotheses that may explain this pattern including metabolic syndrome, immunological responses leading to host tolerance or resistance to infection, and potential changes in consumption rates. Overall, our results suggest that other mechanisms, may drive the consequences of avian malarial infection.