Evaluation of Non-Vector Transmission of Usutu Virus in Domestic Canaries (Serinus canaria).

Usutu virus (USUV) is a flavivirus transmitted to avian species through mosquito bites that causes mass mortalities in wild and captive bird populations. However, several cases of positive dead birds have been recorded during the winter, a vector-free period. To explain how USUV "overwinters", the main hypothesis is bird-to-bird transmission, as shown for the closely related West Nile virus. To address this question, we experimentally challenged canaries with intranasal inoculation of USUV, which led to systemic dissemination of the virus, provided the inoculated dose was sufficient (>102 TCID50). We also highlighted the oronasal excretion of infectious viral particles in infected birds. Next, we co-housed infected birds with naive sentinels, to determine whether onward transmission could be reproduced experimentally. We failed to detect such transmission but demonstrated horizontal transmission by transferring sputum from an infected to a naive canary. In addition, we evaluated the cellular tropism of respiratory mucosa to USUV in vitro using a canary tracheal explant and observed only limited evidence of viral replication. Further research is then needed to assess if and how comparable bird-to-bird transmission occurs in the wild.

Canaries' Microbiota: The Gut Bacterial Communities along One Female Reproductive Cycle.

Investigations of bacterial communities are on the rise both in human and veterinary medicine. Their role in health maintenance and pathogenic mechanisms is in the limelight of infectious, metabolic, and cancer research. Among the most considered, gut bacterial communities take the cake. Their part in animals was assessed mainly to improve animal production, public health, and pet management. In this regard, canaries deserve attention, being a popular pet and source of economic income for bird-keepers, for whom breeding represents a pivotal point. Thus, the present work aimed to follow gut bacterial communities' evolution along on whole reproductive cycle of 12 healthy female canaries. Feces were collected during parental care, molting, and resting phase, and submitted for 16S rRNA sequencing. Data were analyzed and a substantial presence of Lactobacillus aviarius along all the phases, and a relevant shift of microbiota during molting and rest due to an abrupt decrease of the Vermiphilaceae family were detected. Although the meaning of such change is not clear, future research may highlight unforeseen scenarios. Moreover, Lactobacillus aviarius may be deemed for normal bacteria flora restoration in debilitated birds, perhaps improving their health and productivity.

Prosociality and reciprocity according to parental status, communication, and personality in domestic canaries (Serinus canaria).

Prosociality (behaviours that benefit to a recipient without necessarily involving a cost to the actor) has recently been shown to exist in various taxa, including birds. Studies on prosociality in primates found that prosocial tendencies of the subject could be related to sex and parental care, communication from the recipient, cognitive abilities and personality. To investigate the existence of such associations on birds, we conducted a Prosocial Choice Task with domestic canaries (Serinus canaria). In our experiment, the subject could choose between three options: a prosocial, a selfish, and a null option (with no cost for the subject). We also conducted a food sharing experiment and measured several personality traits. Our results highlighted high levels of prosociality and a tendency to reciprocity among reproductive mates. We found a higher propensity to be prosocial in nulliparous individuals than in individuals that have previously been parents, but better sharing abilities in parents than in nulliparous individuals. When they were recipient, parents also used communication more efficiently than nulliparous subjects. Data suggest that parental expertise could enhance subjects' skills in eliciting prosociality. We also highlighted some interaction between prosociality, learning abilities, and some personality traits, proactive individuals being fast learners and more prosocial, while reactive individuals being slow learners and more reciprocal. Our results suggest that prosociality and reciprocity could be linked to personality and cognitive abilities, and that it might be interesting to consider them as parts of individual's cognitive style.

Characterization of multidrug-resistant avian pathogenic Escherichia coli: an outbreak in canaries.

The canary (Serinus canaria) is appreciated for its beautiful song, colors, and docile temperament and drives a lucrative business. However, diseases caused by avian pathogenic Escherichia coli (APEC) compromise the health of canaries, and the inadequate antimicrobial treatment can lead to the emergence of resistant strains. This study aimed to characterize 21 isolates of E. coli obtained from canaries infected with colibacillosis during an outbreak in northern Paraná State, Brazil. APEC and diarrheagenic E. coli (DEC) virulence genes were screened for by polymerase chain reaction (PCR). All isolates were positive for the hlyF, iss, and ompT genes, which are characteristic of APEC. The iroN gene was found in 95.2% of isolates, and none had the iutA gene. The ipaH gene, characteristic of enteroinvasive E. coli (EIEC), was found in 71.4% of isolates, all belonging to the phylogenetic group B1. High genetic similarity (>95%) was found using enterobacterial repetitive intergenic consensus PCR (ERIC-PCR). The isolates belonged to serotypes O117:H4 (71.4%) and O1:H20 (23.8%). This is the first report of a clonal colibacillosis outbreak in canaries caused by APEC. All isolates were resistant to ampicillin, nalidixic acid, ciprofloxacin, enrofloxacin, norfloxacin, and tetracycline. The high rate of multidrug resistance in our study shows the importance of avoiding the inadequate antibiotic treatment. We suggest that further studies should be conducted to contribute to the understanding of colibacillosis in canaries since the health of animals is linked to human and environmental health, as defined by the concept of One Health.

Evaluation of seasonal breeding of the domestic canary (Serinus canaria) in an artificial environment / Avaliação da reprodução sazonal no canário doméstico (Serinus canaria) em ambiente artificial

ABSTRACT: The domestic canary (Serinus canaria) has been bred for hundreds of years to improve the quality of its plumage and its song. Reproduction in this species occurs seasonally, stimulated by a gradual increase in day length. Although, the occurrence of seasonal breeding in canaries is well known, whether canary reproduction can be manipulated remains unknown. Our objective was to determine whether the conditions of captivity (photoperiod and temperature) can be adjusted to enable canaries to reproduce outside of their natural breeding season. Thirty days before the natural breeding season, canary pairs were assigned and separated into three different groups: External Control (housed outdoors under ambient conditions), Artificial Control (housed artificially indoors under conditions similar to the external conditions), and Artificial Altered (housed artificially indoors for five months, with the photoperiod gradually manipulated to simulate that of the natural breeding season) groups. The number of clutches laid was greater in the Artificial Control than in External Control; however, more birds hatched in the External Control. In the Artificial Altered group, the beginning of the breeding season was delayed when the same parameters were used. Although, further research is needed, this study presents new data to assist in the development of protocols that entail gradual changes in environmental conditions to try to reduce the impacts of the processes on animal welfare.

RESUMO: O canário doméstico (Serinus canaria) tem sido criado há centenas de anos para melhorar a qualidade da plumagem e do canto. A reprodução nesta espécie é sazonal, sendo estimulada por um aumento gradual da duração do dia. Embora a reprodução sazonal de canários seja bem conhecida, ainda não se sabe se a reprodução dos canários pode ser manipulada. O objetivo foi determinar se as condições em cativeiro (fotoperíodo e temperatura) podem ser ajustadas para permitir que os canários se reproduzam fora de sua estação natural de reprodução. Trinta dias antes da estação natural de reprodução, os pares foram designados e separados em grupos: Controle Externo (alojado em gaiolas sob condições ambientais externas); Controle Artificial (alojado em gaiolas mantidas em condições artificiais semelhantes ao lado externo); e Alterado Artificial (alojado em gaiolas mantidas em condições artificiais constantes por cinco meses, após o fotoperíodo foi gradualmente manipulado para simular o da estação natural de reprodução). O número de posturas foi maior no grupo Controle Artificial do que no Controle Externo; entretanto, mais aves eclodiram no Controle Externo. No grupo Alterado Artificial, o início do período reprodutivo foi atrasado considerando os mesmos parâmetros reprodutivos. Embora mais pesquisas sejam necessárias, este estudo apresenta novos dados para auxiliar no desenvolvimento de protocolos que promovam mudanças graduais das condições ambientais visando reduzir os impactos no bem-estar animal.

First report of Dermoglyphus passerinus (Analgoidea: Dermoglyphidae) and Strelkoviacarus sp.(Analgidae: Anomalginae) in canaries (Serinus canaria domestica) in Mexico.

Feather mites are the most numerous group of symbionts permanently associated to birds. They are highly specialized to particular microhabitats on their hosts and most of them may be considered as commensals, but several species are parasites. This manuscript documents for the first time a combined infestation by quill mites Dermoglyphus passerinusGaud, 1974 (Analgoidea: Dermoglyphidae) and feather mites Strelkoviacarus sp.(Analgidae: Anomalginae), in domestic canaries (Serinus canaria domestica) (Linnaeus, 1758) (Passeriformes: Fringillidae) in Mexico City, Mexico. Description of the case, the feather and skin lesions, and findings associated with the infection are presented. This manuscript aims to contribute to the knowledge of mite species that can affect the plumage of Serinus canaria domestica; as well as to the diagnosis and control of these infestations.

Sex-and Region-Dependent Expression of the Autism-Linked ADNP Correlates with Social- and Speech-Related Genes in the Canary Brain.

The activity-dependent neuroprotective protein (ADNP) syndrome is an autistic-like disorder, instigated by mutations in ADNP. This syndrome is characterized by developmental delays, impairments in speech, motor function, abnormal hearing, and intellectual disabilities. In the Adnp-haploinsufficient mouse model, many of these impediments are evident, appearing in a sex-dependent manner. In zebra finch songbird (ZF; Taeniopygia guttata), an animal model used for song/language studies, ADNP mRNA most robust expression is observed in the cerebrum of young males, potentially corroborating with male ZF exclusive singing behavior and developed cerebral song system. Herein, we report a similar sex-dependent ADNP expression profile, with the highest expression in the cerebrum (qRT-PCR) in the brain of another songbird, the domesticated canary (Serinus canaria domestica). Additional analyses for the mRNA transcripts of the ADNP regulator, vasoactive intestinal peptide (VIP), sister gene ADNP2, and speech-related Forkhead box protein P2 (FoxP2) revealed multiple sex and brain region-dependent positive correlations between the genes (including ADNP). Parallel transcript expression patterns for FoxP2 and VIP were observed alongside specific FoxP2 increase in males compared with females as well as VIP/ADNP2 correlations. In spatial view, a sexually independent extensive form of expression was found for ADNP in the canary cerebrum (RNA in situ hybridization). The songbird cerebral mesopallium area stood out as a potentially high-expressing ADNP tissue, further strengthening the association of ADNP with sense integration and auditory memory formation, previously implicated in mouse and human.

Are offspring begging levels exaggerated beyond the parental optimum? Evidence from a bidirectional selection experiment.

Parental care involves elaborate behavioural interactions between parents and their offspring, with offspring stimulating their parents via begging to provision resources. Thus, begging has direct fitness benefits as it enhances offspring growth and survival. It is nevertheless subject to a complex evolutionary trajectory, because begging may serve as a means for the offspring to manipulate parents in the context of evolutionary conflicts of interest. Furthermore, it has been hypothesized that begging is coadapted and potentially genetically correlated with parental care traits as a result of social selection. Further experiments on the causal processes that shape the evolution of begging are therefore essential. We applied bidirectional artificial selection on begging behaviour, using canaries (Serinus canaria) as a model species. We measured the response to selection, the consequences for offspring development, changes in parental care traits, here the rate of parental provisioning, as well as the effects on reproductive success. After three generations of selection, offspring differed in begging behaviour according to our artificial selection regime: nestlings of the high begging line begged significantly more than nestlings of the low begging line. Intriguingly, begging less benefitted the nestlings, as reflected by on average significantly higher growth rates, and increased reproductive success in terms of a higher number of fledglings in the low selected line. Begging could thus represent an exaggerated trait, possibly because parent-offspring conflict enhanced the selection on begging. We did not find evidence that we co-selected on parental provisioning, which may be due to the lack of power, but may also suggest that the evolution of begging is probably not constrained by a genetic correlation between parental provisioning and offspring begging.

Development of Perineuronal Nets during Ontogeny Correlates with Sensorimotor Vocal Learning in Canaries.

Songbirds are a powerful model to study vocal learning given that aspects of the underlying behavioral and neurobiological mechanisms are analogous in many ways to mechanisms involved in speech learning. Perineuronal nets (PNNs) represent one of the mechanisms controlling the closing of sensitive periods for vocal learning in the songbird brain. In zebra finches, PNN develop around parvalbumin (PV)-expressing interneurons in selected song control nuclei during ontogeny and their development is delayed if juveniles are deprived of a tutor. However, song learning in zebra finches takes place during a relatively short period of development, and it is difficult to determine whether PNN development correlates with the end of the sensory or the sensorimotor learning period. Canaries have a longer period of sensorimotor vocal learning, spanning over their first year of life so that it should be easier to test whether PNN development correlates with the end of sensory or sensorimotor vocal learning. Here, we quantified PNN around PV-interneurons in the brain of male canaries from hatching until the first breeding season and analyzed in parallel the development of their song. PNN development around PV-interneurons specifically took place and their number reached its maximum around the end of the sensorimotor learning stage, well after the end of sensory vocal learning, and correlated with song development. This suggests that PNN are specifically involved in the termination of the sensitive period for sensorimotor vocal learning.

Seasonal changes of perineuronal nets and song learning in adult canaries (Serinus canaria).

Songbirds learn their song during a sensitive period of development associated with enhanced neural plasticity. In addition, in open-ended learners such as canaries, a sensitive period for sensorimotor vocal learning reopens each year in the fall and leads to song modifications between successive breeding seasons. The variability observed in song production across seasons in adult canaries correlates with seasonal fluctuations of testosterone concentrations and with morphological changes in nuclei of the song control system (SCS). The sensitive periods for song learning during ontogeny and then again in adulthood could be controlled by the development of perineuronal nets (PNN) around parvalbumin-expressing interneurones (PV) which limits learning-induced neuroplasticity. However, this relationship has never been investigated in the context of adult vocal learning in adult songbirds. Here we explored PNN and PV expression in the SCS of adult male Fife Fancy canaries in relation to the seasonal variations of their singing behaviour. We found a clear pattern of seasonal variation in testosterone concentrations and song production. Furthermore, PNN expression was significantly higher in two specific song control nuclei, the robust nucleus of the arcopallium (RA) and the Area X of the basal ganglia, during the breeding season and during the later stages of sensorimotor song development compared to birds in an earlier stage of sensorimotor development during the fall. These data provide the first evidence that changes in PNN expression could represent a mechanism regulating the closing-reopening of sensitive periods for vocal learning across seasons in adult songbirds.

Parasitism of the nasal mite Sternostoma tracheacolum Lawrence, 1948 (Mesostigmata: Rhinonyssidae) in captive birds in Brazil / Parasitismo do ácaro nasal Sternostoma tracheacolum Lawrence, 1948 (Mesostigmata: Rhinonyssidae) em aves de cativeiro no Brasil

Abstract Nasal mites (Mesostigmata: Rhinonyssidae) are obligatory endoparasites of birds, and the resulting parasitism can be harmful to the host's respiratory system. The nasal mite Sternostoma tracheacolum Lawrence has caused significant respiratory issues, including serious injuries that possibly cause death of the host. In this study, we report two cases of captive birds parasitized by S. tracheacolum. The first case is a histopathological description of S. tracheacolum parasitizing the Gouldian Finch (Chloebia gouldiae) in the southeast region of Brazil, that showed partially or totally absence of the characteristic respiratory epithelium in trachea lumen. The other describes, for the first time, the parasitism of this species in a canary (Serinus canaria) in the northeast region of the country.

Resumo Os ácaros nasais (Mesostigmata: Rhinonyssidae) são endoparasitos obrigatórios das aves, e este parasitismo pode ser prejudicial ao sistema respiratório de seu hospedeiro. A espécie de ácaro nasal Sternostoma tracheacolum Lawrence tem causado importantes problemas respiratórios, incluindo lesões graves que possivelmente causam a morte do hospedeiro. Neste estudo, relatamos dois casos de aves em cativeiro parasitadas por S. tracheacolum. O primeiro caso é uma descrição histopatológica de S. tracheacolum parasitando um Diamante-de-gould (Chloebia gouldiae) na região sudeste do Brasil, mostrando parcial ou total ausência do epitélio respiratório característico do lúmen da traqueia. O outro descreve, pela primeira vez, o parasitismo desta espécie em um canário (Serinus canaria) na região nordeste do país.

Experimental study of micro-habitat selection by ixodid ticks feeding on avian hosts.

Mechanisms of on-host habitat selection of parasites are important to the understanding of host-parasite interactions and evolution. To this end, it is important to separate the factors driving parasite micro-habitat selection from those resulting from host anti-parasite behaviour. We experimentally investigated whether tick infestation patterns on songbirds are the result of an active choice by the ticks themselves, or the outcome of songbird grooming behaviour. Attachment patterns of three ixodid tick species with different ecologies and host specificities were studied on avian hosts. Ixodes arboricola, Ixodes ricinus and Ixodes frontalis were put on the head, belly and back of adult great tits (Parus major) and adult domestic canaries (Serinus canaria domestica) which were either restricted or not in their grooming capabilities. Without exception, ticks were eventually found on a bird's head. When we gave ticks full opportunities to attach on other body parts - in the absence of host grooming - they showed lower attachment success. Moreover, ticks moved from these other body parts to the host's head when given the opportunity. This study provides evidence that the commonly observed pattern of ticks feeding on songbirds' heads is the result of an adaptive behavioural strategy. Experimental data on a novel host species, the domestic canary, and a consistent number of published field observations, strongly support this hypothesis. We address some proximate and ultimate causes that may explain parasite preference for this body part in songbirds. The link found between parasite micro-habitat preference and host anti-parasite behaviour provides further insight into the mechanisms driving ectoparasite aggregation, which is important for the population dynamics of hosts, ectoparasites and the micro-pathogens for which they are vectors.

Effects of Song Experience and Song Quality on Immediate Early Gene Expression in Female Canaries (Serinus canaria).

Female songbirds are thought to make mate choices based on aspects of male song quality. Male canaries (Serinus canaria) produce songs with "special" syllables that have been shown to be highly salient to female listeners - eliciting high rates of sexual displays and enhanced immediate early gene (IEG) expression. Immunohistochemistry for the IEG ZENK was used to examine the effects of experience with these syllables on activity in the caudal mesopallium (CMM) and nidocaudal mesopallium (NCM), two auditory areas important in processing conspecific song. Photostimulated female canaries were housed in sound attenuated chambers and played pseudosongs containing either three special syllables or three non-special syllables, an intro, and an outro sequence. Females that heard special syllable pseudosongs exhibited higher ZENK expression in CMM. To assess the effects of experience, photostimulated females were pair housed and exposed to playback of song with or without special syllables for 14 days. After transfer to individual housing, birds were played one of the aforementioned stimuli or silence. ZENK expression in CMM and NCM was equivalent for song with and without special syllables, but significantly lower for silence. Females who experienced song with special syllables had lower plasma estradiol concentrations after final song playback. This study indicates that CMM exhibits an IEG response bias to special syllables in limited acoustic contexts, but not in full song, which may contain additional biologically relevant information. Furthermore, estradiol concentrations may mediate changes in song responses, serving as a mechanism for modulating mate choice in differing song environments.

Detection of Enterobacteriaceae, antimicrobial susceptibility, and virulence genes of Escherichia coli in canaries (Serinus canaria) in northeastern Brazil / Detecção de enterobactérias, sensibilidade antimicrobiana e genes de virulência de Escherichia coli em canários belgas (Serinus canaria) da região Nordeste do Brasil

This study aimed to verify the presence of members from the Enterobacteriaceae family and determine antimicrobial susceptibility profiles of the isolates in canaries bred in northeastern Brazil; in addition, the presence of diarrheagenic Escherichia coli (DEC) and avian pathogenic Escherichia coli (APEC) was also verified in these birds. Samples were collected during an exhibition organized by the Brazilian Ornithological Federation in July 2015 in Fortaleza, Brazil. A total of 88 fecal samples were collected and submitted to pre-enrichment step using buffered peptone water, followed by enrichment with the following broths: brain-heart infusion, Rappaport-Vassiliadis, and Selenite-Cystine. Subsequently, aliquots were streaked on MacConkey, brilliant green and salmonella-shigella agar plates. Colonies were selected according to morphological characteristics and submitted to biochemical identification and antimicrobial susceptibility tests with disk-diffusion technique. E. coli strains were evaluated for the presence of eight DEC genes and five APEC genes through conventional polymerase chain reaction (PCR) screening. The most frequent species observed were Pantoea agglomerans (25%), Serratia liquefaciens (12.5%), and Enterobacter aerogenes (9.1%). A single rough strain of Salmonella enterica subsp. enterica was identified in one sample (1.1%). High resistance rates to amoxicillin (78.7%) and ampicillin (75.4%) were identified. Polymyxin B (9.8%), gentamycin (6.6%), and enrofloxacin (6.6%) were the most efficient antibiotics. The total number of multidrug-resistant strains (isolates resistant to more than three antimicrobial classes) was 23 (37.7%). Four E. coli strains were tested for the virulence genes, and two were positive for APEC virulence genes: one strain was positive for iutA and the other for hlyF. In conclusion, canaries in northeastern Brazil participating in exhibitions may present Salmonella spp., Escherichia coli and other enterobacteria in the intestinal microbiota with antimicrobial resistance. These results indicate that, although the E. coli strains recovered from canaries in this study have some virulence genes, they still do not fulfill all the requirements to be considered APEC.(AU)

O objetivo deste trabalho foi verificar a presença de enterobactérias e determinar o perfil de sensibilidade aos antimicrobianos dos isolados oriundos de canários belgas criados em cativeiro do Nordeste do Brasil, adicionalmente verificou-se a presença de Escherichia coli diarreiogênicas (DEC) e E. coli patogênica aviária (APEC) nesses animais. A colheita das amostras ocorreu durante uma exposição de canários belgas organizada pela Federação Ornitológica do Brasil (FOB), em julho de 2015, na cidade de Fortaleza, Ceará, Brasil. Um total de 88 amostras de fezes foram coletadas e submetidas a pré-enriquecimento utilizando água peptonada, caldo de enriquecimento Brain Heart Infusion, Rappaport-Vassiliadis e Selenito-Cistina. Fez-se triagem em placas de ágar MacConkey, Verde Brilhante e ágar Salmonella Shigella. As colônias foram selecionadas e submetidas à identificação bioquímica e susceptibilidade antimicrobiana. Estirpes de Escherichia coli foram avaliadas quanto a presença de 8 genes de virulência de DEC e cinco de APEC por reação em cadeia da polimerase convencional (PCR). As enterobactérias encontradas com maior frequência foram Pantoea agglomerans (25%), Serratia liquefaciens (12,5%) e Enterobacter aerogenes (9,1%). Uma única estirpe de Salmonella enterica subsp. enterica (rugosa) esteve presente em um dos isolados (1,1%). Altos percentuais de resistência foram encontrados para dois antibióticos: amoxicilina (78,7%) e ampicilina (75,4%). Polimixina B (9,8%), gentamicina (6,8%) e enrofloxacina (6,5%) foram os antibióticos com melhor eficiência. O total de estirpes multirresistentes (a mais de três classes de antimicrobianos) foi de 23 (37,7%). Das quatro estirpes de E. coli isoladas, duas foram positivas para os genes de APEC, sendo uma estipe para o gene iss e outra para os genes iutA e hlyF. Portanto, canários belgas criados em cativeiro no Brasil que participam de exposições podem apresentar Salmonella spp., Escherichia coli e outras enterobactérias em sua microbiota intestinal com resistência antimicrobiana. Estes resultados indicam que as estirpes de E. coli isoladas de canário belga no presente estudo apresentam alguns, mas não todos, genes de virulência para serem caracterizadas como E. coli patogênica para aves (APEC).(AU)

Flexible communication within bird families-The consequences of behavioral plasticity for parent-offspring coadaptation.

Offspring are selected to demand more resources than what is optimal for their parents to provide, which results in a complex and dynamic interplay during parental care. Parent-offspring communication often involves conspicuous begging by the offspring which triggers a parental response, typically the transfer of food. So begging and parental provisioning reciprocally influence each other and are therefore expected to coevolve. There is indeed empirical evidence for covariation of offspring begging and parental provisioning at the phenotypic level. However, whether this reflects genetic correlations of mean levels of behaviors or a covariation of the slopes of offspring demand and parental supply functions (= behavioral plasticity) is not known. The latter has gone rather unnoticed-despite the obvious dynamics of parent-offspring communication. In this study, we measured parental provisioning and begging behavior at two different hunger levels using canaries (Serinus canaria) as a model species. This enabled us to simultaneously study the plastic responses of the parents and the offspring to changes in offspring need. We first tested whether parent and offspring behaviors covary phenotypically. Then, using a covariance partitioning approach, we estimated whether the covariance predominantly occurred at a between-nest level (i.e., indicating a fixed strategy) or at a within-nest level (i.e., reflecting a flexible strategy). We found positive phenotypic covariation of offspring begging and parental provisioning, confirming previous evidence. Yet, this phenotypic covariation was mainly driven by a covariance at the within-nest level. That is parental and offspring behaviors covary because of a plastic behavioral coadjustment, indicating that behavioral plasticity could be a main driver of parent-offspring coadaptation.

Outbreak of Systemic Avian Pox in Canaries (Serinus canaria domestica) Associated with the B1 Subgroup of Avian Pox Viruses.

This study reports an outbreak of avian pox in a quarantine of canaries imported from Europe, with a mortality of 30% and clinical signs of dyspnea and blepharoconjunctivitis. During necropsy, beak cyanosis, serous blepharitis, caseous sinusitis, oropharyngitis, tracheitis, pulmonary edema, pneumonia, fibrinous airsacculitis, and splenomegaly were observed. Microscopically, edema, epithelial hyperplasia, hydropic degeneration, and vacuolated eosinophilic intracytoplasmic inclusion bodies were found; similar lesions were observed in the thymus, spleen, and other organs. The virus was isolated in chicken embryos, and it was identified and characterized using a sequence of 913 nucleotides of the DNA polymerase gene. Pathologic characteristics and molecular biology indicate the systemic presence of avian pox associated with an avipoxvirus of the B1 subgroup. Additionally, other lesions associated with Aspergillus sp., Macrorhabdus ornithogaster, and Isospora sp. were found, which could contribute to the high mortality. Canarypox virus should be considered a differential diagnosis in cases of dyspnea and high mortality in canary flocks.

Reporte de caso- Brote de viruela aviar sistémica en canarios (Serinus canaria domestica) asociado con el virus de la viruela aviar subgrupo B1. En este estudio se reporta un brote de viruela aviar en unos canarios importados de Europa que estaban bajo cuarentena, con una mortalidad del 30% y signos clínicos de disnea y blefaroconjuntivitis. Durante la necropsia, se observó cianosis de pico, blefaritis serosa, sinusitis caseosa, orofaringitis, traqueítis, edema pulmonar, neumonía, fibrinosa respiratoria y esplenomegalia. Microscópicamente, se encontró edema, hiperplasia epitelial, degeneración hidrópica y cuerpos de inclusión intracitoplásmicos eosinófilos vacuolados; Se observaron lesiones similares en el timo, el bazo y otros órganos. El virus se aisló en embriones de pollo, se identificó y caracterizó analizando una secuencia de 913 nucleótidos del gene de la polimerasa de ADN. Las características patológicas y la biología molecular indican la presentación sistémica de la viruela aviar asociada a un avipoxvirus del subgrupo B1. Además, se encontraron otras lesiones asociadas con Aspergillus sp., Macrorhabdus ornithogaster y Isopora sp., lo que pudo contribuir a la alta mortalidad. El virus de la viruela del canario debe considerarse un diagnóstico diferencial en casos de disnea y alta mortalidad en parvadas de canarios.

Parasitism of the nasal mite Sternostoma tracheacolum Lawrence, 1948 (Mesostigmata: Rhinonyssidae) in captive birds in Brazil

Nasal mites (Mesostigmata: Rhinonyssidae) are obligatory endoparasites of birds, and the resulting parasitism can be harmful to the host’s respiratory system. The nasal mite Sternostoma tracheacolum Lawrence has caused significant respiratory issues, including serious injuries that possibly cause death of the host. In this study, we report two cases of captive birds parasitized by S. tracheacolum. The first case is a histopathological description of S. tracheacolum parasitizing the Gouldian Finch (Chloebia gouldiae) in the southeast region of Brazil, that showed partially or totally absence of the characteristic respiratory epithelium in trachea lumen. The other describes, for the first time, the parasitism of this species in a canary (Serinus canaria) in the northeast region of the country.

The canary Serinus canaria (Passeriformes: Fringillidae) as a new host for Isospora bioccai in Mexico.

Isospora bioccai (Cringoli and Quesada 1991) (Protozoa, Apicomplexa, Eimeriidae) is reported and described from captive canaries Serinus canaria forma domestica (Linnaeus 1758) in Mexico. The oöcysts are subspherical, 25.5 × 23.5 µm, with smooth, bilayered wall, ∼1.3 µm thick. Micropyle absent, oöcyst residuum absent, and polar granule present, 4-8 rice-grain-shaped. Sporocysts are ovoidal, 16.7 × 10.5 µm. Stieda body knob-like and substieda body trapezoidal of irregular base. Sporocyst residuum is composed of granules of different sizes. Sporozoites are vermiform with one refractile body and a nucleus. Gamogony was seen in the duodenum. In addition to new locality, this is the first description of I. bioccai from S. canaria.

The effect of dietary antioxidant supplementation in a vertebrate host on the infection dynamics and transmission of avian malaria to the vector.

Host susceptibility to parasites is likely to be influenced by intrinsic factors, such as host oxidative status determined by the balance between pro-oxidant production and antioxidant defences. As a result, host oxidative status acts as an environmental factor for parasites and may constrain parasite development. We evaluated the role of host oxidative status on infection dynamics of an avian malarial parasite by providing canaries (Serinus canaria) with an antioxidant supplementation composed of vitamin E (a lipophilic antioxidant) and olive oil, a source of monounsaturated fatty acids. Another group received a standard, non-supplemented food. Half of the birds in each group where then infected with the haemosporidian parasite, Plasmodium relictum. We monitored the parasitaemia, haematocrit level, and red cell membrane resistance, as well as the transmission success of the parasite to its mosquito vector, Culex pipiens. During the acute phase, the negative effect of the infection was more severe in the supplemented group, as shown by a lower haematocrit level. Parasitaemia was lower in the supplemented group during the chronic phase only. Mosquitoes fed on supplemented hosts were more often infected than mosquitoes fed on the control group. These results suggest that dietary antioxidant supplementation conferred protection against Plasmodium in the long term, at the expense of a short-term negative effect. Malaria parasites may take advantage of antioxidants, as shown by the increased transmission rate in the supplemented group. Overall, our results suggest an important role of oxidative status in infection outcome and parasite transmission.

Avian malaria and bird humoral immune response.

BACKGROUND: Plasmodium parasites are known to impose fitness costs on their vertebrate hosts. Some of these costs are due to the activation of the immune response, which may divert resources away from self-maintenance. Plasmodium parasites may also immuno-deplete their hosts. Thus, infected individuals may be less able to mount an immune response to a new pathogen than uninfected ones. However, this has been poorly investigated. METHODS: The effect of Plasmodium infection on bird humoral immune response when encountering a novel antigen was tested. A laboratory experiment was conducted on canaries (Serinus canaria) experimentally infected with Plasmodium relictum (lineage SGS1) under controlled conditions. Birds were immune challenged with an intra-pectoral injection of a novel non-pathogenic antigen (keyhole limpet haemocyanin, KLH). One week later they were challenged again. The immune responses to the primary and to the secondary contacts were quantified as anti-KLH antibody production via enzyme-linked immunosorbent assay (ELISA). RESULTS: There was no significant difference in antibody production between uninfected and Plasmodium infected birds at both primary and secondary contact. However, Plasmodium parasite intensity in the blood increased after the primary contact with the antigen. CONCLUSIONS: There was no effect of Plasmodium infection on the magnitude of the humoral immune response. However, there was a cost of mounting an immune response in infected individuals as parasitaemia increased after the immune challenge, suggesting a trade-off between current control of chronic Plasmodium infection and investment against a new immune challenge.