The deeper the rounder: body shape variation in lice parasitizing diving hosts.

Seal lice, unique among insects, show remarkable adaptability to the extreme conditions of the deep sea. Evolving with their seal and sea lion hosts, they have managed to tolerate hypoxia, high salinity, low temperature, and elevated hydrostatic pressure. Given the diving capabilities of their mammalian hosts, which can reach depths of hundreds to thousands of meters, our study examines the morphological variation among closely related seal lice species infesting hosts with different maximum diving depths. In particular, our research reveals a significant morphological difference between lice associated with regular and deep-diving hosts, where lice from deep-diving hosts tend to be rounder. This could be an adaptation to withstand the high hydrostatic pressures found in the deep ocean. The rounded shape optimizes the louse's ability to withstand external pressure by redistributing it over a larger ventral/dorsal plane. This in turn minimizes the internal energy required to support body deformations, thereby increasing the louse's resilience in the deep sea environment.

First record of ectoparasites (Phthiraptera and Acari) from the Andean condor (Vultur gryphus) in Colombia.

Several species of ectoparasites, including chewing lice and mites are closely associated with their hosts. The Andean condor (Vultur gryphus) is globally listed as vulnerable by the IUCN and its population has been steadily declining in recent decades suggesting a potential extinction of associated entomofauna. The purpose of this study was to record the species of ectoparasites infesting three individuals of Andean condor found dead in the 'Páramo del Almorzadero' Santander Department, Northeastern Colombia. One juvenile (male) and two adults (male and female) Andean condors received for necropsy were carefully examined for ectoparasite infestation. Specimens were collected and preserved in ethanol (70%) for taxonomic studies. Morphologic identification and morphometric records were made under light microscopy. Some specimens were also prepared for scanning electron microscopy and others were subjected to DNA extraction to amplify and obtain sequences of the cytochrome-C oxidase subunit I (COI) gene for phylogenetic analyses. Lice were collected from the juvenile condor and the adult female and identified as Falcolipeurus assesor (Phthiraptera: Ischnocera) in the juvenile condor (8 females, 19 males and 8 nymphs) and the adult (1 female); Colpocephalum trichosum (Phthiraptera: Amblycera) in the juvenile (19 females, 24 males and 1 nymph) and the adult (2 females, 2 males and 3 nymphs); and Cuculiphilus zonatus (Phthiraptera: Amblycera) in the juvenile (40 females, 43 males and 15 nymphs) and the adult (1 male and 2 nymphs). Moreover, one mite collected from the juvenile condor was identified as Ancyralges cathartinus (Acari: Astigmata) (1 female). Morphometric data was obtained for the adult stages of F. assesor (6 females and 13 males), C. trichosum (9 females and 9 males) and C. zonatus (10 females and 10 males). We obtained the first DNA sequences of COI for F. assessor, and C. trichosum, where phylogenetic tree analysis showed that F. assessor is more closely related to Falcolipeurus marginalis, and C. trichosum to Colpocephalum kelloggi. This represents the first record of parasites in Andean condor from Colombia and contributes to the knowledge of chewing lice and mites associated with an endemic and endangered bird species. Further studies on Andean condor ectoparasites should be focused on documenting host-parasite interactions and potential health impacts in these wild birds.

Varias especies de ectoparásitos, incluidos piojos masticadores y ácaros están estrechamente asociados a sus hospedadores. El cóndor andino (Vultur gryphus) está catalogado por la UICN como una especie vulnerable y su población ha ido disminuyendo constantemente en las últimas décadas, lo que sugiere una posible extinción de la entomofauna asociada. El propósito de este estudio fue registrar las especies de ectoparásitos infestando a tres individuos de cóndor andino encontrados muertos en el Páramo del Almorzadero, Departamento de Santander, Noreste de Colombia. Un cóndor andino juvenil (macho) y dos adultos (macho y hembra) recibidos para necropsia fueron examinados cuidadosamente para detectar infestación por ectoparásitos. Los especímenes fueron recolectados y preservados en etanol (70%) para estudios taxonómicos. La identificación morfológica y los registros morfométricos se ejecutaron bajo microscopía óptica. Algunas muestras también se prepararon para microscopía electrónica de barrido y otras se sometieron a extracción de ADN para amplificar y obtener secuencias del gen de la subunidad I (COI) del citocromo­C oxidasa para análisis filogenéticos. Los piojos recolectados del cóndor juvenil y de la hembra adulta se identificaron como Falcolipeurus assesor (Phthiraptera: Ischnocera) en el cóndor juvenil (8 hembras, 19 machos y 8 ninfas) y en el adulto (1 hembra); Colpocephalum trichosum (Phthiraptera: Amblycera) en el juvenil (19 hembras, 24 machos y 1 ninfa) y en el adulto (2 hembras, 2 machos y 3 ninfas); y Cuculiphilus zonatus (Phthiraptera: Amblycera) en el juvenil (40 hembras, 43 machos y 15 ninfas) y en el adulto (1 macho y 2 ninfas). Además, un ácaro recolectado del cóndor juvenil fue identificado como Ancyralges cathartinus (Acari: Astigmata) (1 hembra). Se obtuvieron datos morfométricos para los estadios adultos de F. assesor (6 hembras y 13 machos), C. trichosum (9 hembras y 9 machos) y C. zonatus (10 hembras y 10 machos). Secuencias de ADN basadas en COI para las especies F. assesor y C. trichosum son reportadas por la primera vez, donde el análisis filogenetico mostró que F. assesor está más estrechamente relacionado con Falcolipeurus marginalis y C. trichosum con Colpocephalum kelloggi. Este representa el primer registro de parásitos en cóndor andino de Colombia y contribuye al conocimiento de los piojos masticadores y ácaros asociados a una especie de ave endémica de los Andes y en peligro de extinción. Otros estudios sobre los ectoparásitos del cóndor andino deberían centrarse en documentar las interacciones hospedador­parásito y los posibles impactos en la salud de estas aves silvestres.

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.

Measuring local genetic variation in permethrin-resistant head lice (Phthiraptera: Pediculidae) from Buenos Aires, Argentina.

The cosmopolitan ectoparasite human head louse, Pediculus humanus capitis (De Geer)(Phthiraptera:Pediculidae), affects mostly school-aged children, with infestations reported every year mainly due to louse resistance to pyrethroids. One of the main resistance mechanisms of pyrethroids is the target site insensitivity (kdr), which is caused by single-nucleotide point mutations (SNPs) located in the voltage-sensitive sodium channel gene. In this study, we analyzed individual head lice toxicologically via the description of their susceptibility profile to permethrin and genetically through the genotypification of their kdr alleles as well as nuclear microsatellite loci. Lice were collected from 4 schools in the city of Buenos Aires, Argentina. The resistance ratios varied from 33.3% to 71.4%, with a frequency of the T917I kdr mutation of 87.31% and with 83.6% of the head lice being homozygous resistant to pyrethroids. Microsatellite data indicated that all the louse school populations had genotype proportions that deviated from Hardy-Weinberg expectations, with FIS > 0 reflecting a deficit of heterozygotes. Bottleneck analysis suggested that all louse school populations underwent a recent reduction in population sizes, while 3 of the 4 schools had gene flow values around 1, indicating ongoing gene flow among those schools. Our study suggests that school louse populations in the city of Buenos Aires may form a metapopulation, where each school represents a small population that undergoes extinction and recolonization processes under strong permethrin selection. This is the first multilevel analysis integrating toxicological, kdr-genotyping, and microsatellite data in human louse populations.

Cuticular extracts induce aggregation in head lice.

The human head lice Pediculus humanus capitis (De Geer) (Phthiraptera: Pediculidae) are strict, obligate human ectoparasites that spends their entire life cycle in the host and cause skin irritation and derived infections. Despite the health-related importance, few studies have evaluated the chemical communication among these insects. Here, we evaluate the response of lice of both sexes to cuticular extracts using two solvents of different polarity (hexane and methanol). Cuticular extracts that elicited an attraction response towards head lice were analysed by gas chromatography-mass spectrometry (GC-MS) to determine the cuticular lipid profile. Both lice sexes were attracted to the hexane extracts but not the methanol extracts, suggesting the non-polarity of the compounds present in the cuticle. Chemical analyses of hexane extracts from males and females showed high similarity in major compounds. This study provides the first evidence that lice respond to cuticle extracts, which may be important to understand aggregation behaviour.

Parasitic findings on threatened pudu deer from Central Chile accounts first genetic characterization of lice parasitizing P. puda in Chile and the first molecular report of Taenia hydatigena metacestodes in this species.

Southern pudu (Pudu puda) is a threatened endemic deer of the temperate forests of Chile. In recent years pudu populations rates have decreased mainly due to anthropogenic causes including forest loss and landscape fragmentation. In this context, the parasitic fauna of Chilean pudu has been scarcely investigated. The aim of this study was to determine the parasitic status of rescued pudu n = 13 from its natural habitat in Central Chile (Maule region) during March 2022 and June 2023 by applying morphological, histopathological, and molecular analyses. As result, we report the presence of transmission of parasites from dogs to pudus as showed by the presence of metacestodes of the parasite Taenia hydatigena on omentum, liver, and pleura of pudus during postmortem examinations, being the first molecular report on the presence of this parasite on Chilean pudu. Meanwhile, ectoparasite examinations determined the presence of chewing and sucking lice on pudu exemplars here analysed. Molecular and phylogenetic analysis of lice revealed new insights on Bovicola and Anoplura lice parasitizing P. puda in Chile, equally being the first genetic characterization of lice parasitizing pudu exemplars in Chile. In addition, parasite loads of lice and metacestodes were analysed. However, no statistically significance was observed when comparing environmental and individual traits influence on parasite load variation. Overall, the study area is the northern limit of habitat distribution of this specie in Chile and we here provide novel information on pudu deer parasites, thus making a useful and valuable contribution to the parasitological knowledge on this threatened species.

DO PARASITIC LICE EXHIBIT ENDEMISM IN PARALLEL WITH THEIR AVIAN HOSTS? A COMPARISON ACROSS NORTHERN AMAZONIAN AREAS OF ENDEMISM.

Areas of endemism are the smallest units in biogeography and can be defined as biologically unique areas comprising taxa with common geographic limits to their distributions. High beta diversity within Amazonia is often related to turnover among these areas. For decades, evolutionary biologists have tried to comprehend the mechanisms generating and maintaining the spatial structure and high diversity of free-living Amazonian organisms, particularly birds. However, few studies have tried to analyze these patterns among their parasites. Host and parasite associations involve shared history that may allow us to better understand the fine-scale evolutionary history of the host. Here we compare the coevolutionary patterns among 2 avian host species with distinct patterns of genetic structure in northern Amazonia, Dendrocincla fuliginosa (Aves: Dendrocolaptidae) and Dixiphia pipra (Aves: Pipridae), and their ectoparasitic lice (Insecta: Phthiraptera), Furnaricola sp. ex Dendrocincla fuliginosa, Myrsidea sp. ex Dixiphia pipra, and Tyranniphilopterus sp. ex Dixiphia pipra. We obtained sequences of the mitochondrial gene cytochrome oxidase subunit I from hosts and parasites collected on opposite banks of the Negro and Japurá rivers, which delimit 3 areas of endemism in northern Amazonia: Napo, Jau, and Guiana. Our results demonstrate that the Negro River is a geographical barrier for both Furnaricola sp. and its avian host, Dendrocincla fuliginosa. Phylogenies of both hosts, Dendrocincla fuliginosa, and the parasites, Furnaricola sp., show monophyletic clades on opposite margins of the river that are not sister taxa. These clades have a mean uncorrected p-distance of 17.8% for Furnaricola sp. and 6.0% for Dendrocincla fuliginosa. Thus, these parasite clades constitute distinct evolutionary lineages and may even be distinct species. In contrast, Dixiphia pipra has no population structure associated with either river. Accordingly, data from their lice Myrsidea sp. indicate weak support for different clades on opposite margins of the Negro River, whereas data from their lice Tyranniphilopterus sp. indicate weak structure across the Japurá. This study is a first step toward understanding the effects of biogeographic history on permanent ectoparasites and suggests that host biogeographic history is to some extent a determinant of the parasite's history. Furthermore, the parasite's evolutionary history is an additional source of information about their hosts' evolution in this highly diverse region of northern Amazonia.

Heritability of Immunity Traits and Resistance of Atlantic Salmon against the Sea Louse Caligus rogercresseyi.

The immune response of Atlantic salmon to sea lice has been extensively studied, but we still do not know the mechanisms by which some fish become resistant and others do not. In this study, we estimated the heritabilities of three key proteins associated with the innate immunity and resistance of Salmo salar against the sea louse Caligus rogercresseyi. In particular, we quantified the abundance of 2 pro-inflammatory cytokines, Tnfα and Il-8, and an antioxidant enzyme, Nkef, in Atlantic salmon skin and gill tissue from 21 families and 268 individuals by indirect ELISA. This covers a wide parasite load range from low or resistant (mean sea lice ± SE = 8.7 ± 0.9) to high or susceptible (mean sea lice ± SE = 43.3 ± 2.0). Our results showed that susceptible fish had higher levels of Nkef and Tnfα than resistant fish in their gills and skin, although gill Il-8 was higher in resistant fish, while no significant differences were found in the skin. Furthermore, moderate to very high heritable genetic variation was estimated for Nkef (h2 skin: 0.96 ± 0.14 and gills: 0.97 ± 0.11) and Tnfα (h2 skin: 0.53 ± 0.17 and gills: 0.32 ± 0.14), but not for Il-8 (h2 skin: 0.22 ± 0.12 ns and gills: 0.09 ± 0.08 ns). This work provides evidence that Nkef and Tnfα protein expressions are highly heritable and related to resistance against sea lice in Atlantic salmon.

First report of parasitism by Eutrichophilus cercolabes (Phthiraptera: Trichodectidae) on Coendou spinosus (Erethizontidae) in Rio Grande do Sul, Brazil - case report.

Coendou spinosus is a species of rodent popularly known as porcupine, it has a great ability to adapt to different habitats and is found in tropical forests in countries such as Bolivia, Brazil, Venezuela and Guianas. This mammal has already been identified as a reservoir of several pathogenic agents for humans and other animals and has a variety of ectoparasites, endoparasites and hemoparasites little studied and described. Due to this, the objective was to report the parasitism by Eutrichophilus cercolabes in C. spinosus in the central region of Rio Grande do Sul, southern Brazil. In total, 16 lice were found, one male and 15 females of the species. This is the first report of the parasitism of this Phthiraptera on C. spinosus in Rio Grande do Sul. The scarcity of reports on the taxonomy and biotic characteristics, as well as the vector capacity of pathogens of most species of ectoparasites of wild animals, highlights the need for further studies on the distribution of these arthropods in different regions and host species.

Coendou spinosus é uma espécie de roedor conhecida popularmente por porco-espinho, possui uma grande capacidade de adaptação a diferentes habitats sendo encontrada em florestas tropicais de países como Bolívia, Brasil, Venezuela e Guianas. Esse mamífero já foi identificado como reservatório de vários agentes patogênicos para o homem e outros animais e possui uma variedade de ectoparasitos, endoparasitos e hemoparasitos pouco estudados e descritos. Devido a isso, objetivou-se relatar o parasitismo por Eutrichophilus cercolabes em C. spinosus na região central do Rio Grande do Sul, Sul do Brasil. Ao total, foram encontrados 16 piolhos, sendo um macho e 15 fêmeas da espécie. Esse é o primeiro relato do parasitismo deste Phthiraptera em C. spinosus no Rio Grande do Sul. A escassez de relatos sobre a taxonomia e características bióticas, bem como a capacidade vetorial de patógenos da maioria das espécies de ectoparasitos de animais silvestres evidencia a necessidade da realização de mais estudos sobre a distribuição desses artrópodes em diferentes regiões e espécies hospedeiras.

New records, and molecular detection of vector-borne pathogens in Felicola subrostratus from eastern Mexico.

The study of lice associated with domestic cats is a neglected area of veterinary parasitology. In particular, the presence of the cat louse Felicola subrostratus, a small Ischnoceran species found in the fur of the domestic cat, is rarely recognized. In America, this species has been reported across six countries. Although it was also recently reported in Mexico, no studies on the molecular identification of the specimens or the monitoring of potential bacterial, and protozoan pathogens have been carried out. Thus, this work aimed to collect, and identify lice associated with domestic and free ranging cats from the states of Veracruz and Tabasco, using amplification and sequencing of the mitochondrial cytochrome c oxidase subunit I (COI), and the ribosomal 18S rDNA genes, and to monitor selected vector-borne bacterial (Bartonella, Mycoplasma, and Rickettsia) and protozoan (Babesia, and Hepatozoon) agents. Only entire lice were used for molecular host and pathogen identification. Eighty-one lice, identified as F. subrostratus, were recovered from five infested cats, and 30 were selected for molecular identification and pathogen surveillance. Analysis of the COI and 18S rDNA partial sequences showed a similarity of 96.79%-100% with sequences of F. subrostratus from the US. Mycoplasma haemofelis and Hepatozoon canis DNA was detected in three and four samples, respectively. This work provides new collection locations for F. subrostratus, and the first sequences of the COI and 18S rDNA genes from Mexico. It also reports two pathogenic microorganisms found in the lice.

External and gastrointestinal parasites of the black-faced ibis Theristicus melanopis (Pelecaniformes: Threskiornithidae) in the Los Ríos region, southern Chile.

The black-faced ibis, Theristicus melanopis, is considered a useful bird species for agricultural activity because it preys upon various invertebrate and vertebrate pests. Although it is a common species in Chile, limited information is available regarding its parasites. The main objective of this study was to recover the diversity of ectoparasites and gastrointestinal helminths in black-faced ibises living in the communes of Valdivia and Panguipulli, Los Ríos region. A total of 74 specimens were received for examination from the Centro de Rehabilitación de Fauna Silvestre at the Universidad Austral de Chile (CEREFAS-UACh), Valdivia, in 2011-2015. Black-faced ibises were externally inspected for ectoparasites by direct examining of the plumage, and necropsies were performed to examine digestive and respiratory organs in search of endoparasites. For each taxon, prevalence, mean intensity, mean abundance, and range of parasites per bird were estimated. Five species of ectoparasites and six species of helminths were identified. A total of 298 lice (Insecta: Phthiraptera) belonging to four species were collected: Ardeicola melanopis (13.51%), Colpocephalum trispinum (20.27%), Ibidoecus fissisignatus (4.05%), and Plegadiphilus mamillatus (9.46%). In addition, one feather mite species, Diodochaetus melanopis (Acari: Pterolichoidea) (17.56%), was isolated. In 48 black-faced ibis (64.86%), a total of 1229 gastrointestinal helminths were found: two nematodes, Porrocaecum heteropterum (55.41%) and Baruscapillaria obsignata (24.32%); one tapeworm Eugonodaeum nasuta (20.27%); two digeneans, Echinoparyphium recurvatum (1.35%) and Strigea bulbosa (6.76%); and the acanthocephalan Sphaerirostris sp. (1.35%). The findings of the following parasites present new host-parasite associations: P. mamillatus, D. melanopis, B. obsignata, E. recurvatum, S. bulbosa, and Sphaerirostris sp. Additionally, the louse P. mamillatus, feather mite D. melanopis, platyhelminths E. nasuta, E. recurvatum and S. bulbosa, and the acanthocephalan Sphaerirostris sp. are new records for the fauna of Chile.

Transcriptome Signatures of Atlantic Salmon-Resistant Phenotypes against Sea Lice Infestation Are Associated with Tissue Repair.

Salmon aquaculture is constantly threatened by pathogens that impact fish health, welfare, and productivity, including the sea louse Caligus rogercresseyi. This marine ectoparasite is mainly controlled through delousing drug treatments that have lost efficacy. Therein, strategies such as salmon breeding selection represent a sustainable alternative to produce fish with resistance to sea lice. This study explored the whole-transcriptome changes in Atlantic salmon families with contrasting resistance phenotypes against lice infestation. In total, 121 Atlantic salmon families were challenged with 35 copepodites per fish and ranked after 14 infestation days. Skin and head kidney tissue from the top two lowest (R) and highest (S) infested families were sequenced by the Illumina platform. Genome-scale transcriptome analysis showed different expression profiles between the phenotypes. Significant differences in chromosome modulation between the R and S families were observed in skin tissue. Notably, the upregulation of genes associated with tissue repairs, such as collagen and myosin, was found in R families. Furthermore, skin tissue of resistant families showed the highest number of genes associated with molecular functions such as ion binding, transferase, and cytokine activity, compared with the susceptible. Interestingly, lncRNAs differentially modulated in the R/S families are located near genes associated with immune response, which are upregulated in the R family. Finally, SNPs variations were identified in both salmon families, where the resistant ones showed the highest number of SNPs variations. Remarkably, among the genes with SPNs, genes associated with the tissue repair process were identified. This study reported Atlantic salmon chromosome regions exclusively expressed in R or S Atlantic salmon families' phenotypes. Furthermore, due to the presence of SNPs and high expression of tissue repair genes in the resistant families, it is possible to suggest mucosal immune activation associated with the Atlantic salmon resistance to sea louse infestation.

Grooming Time Predicts Survival: American Kestrels, Falco sparverius, on a Subtropical Island.

AbstractAnimals have evolved a variety of adaptations to care for their body surfaces, such as grooming behavior, which keeps the integument clean, parasite-free, and properly arranged. Despite extensive research on the grooming of mammals, birds, and arthropods, the survival value of grooming has never been directly measured in natural populations. We monitored grooming and survival in a population of marked American kestrels (Falco sparverius) on San Salvador Island, Bahamas. We found a strong association between time spent grooming and survival over a 2-year period. The quadratic relationship we show is consistent with stabilizing natural selection on grooming time. To our knowledge, this is the first evidence for a correlation between grooming time and survival in a natural population. Grooming time may predict the survival of many animal taxa, but additional studies are needed to determine the shape and strength of the relationship among birds, mammals, and arthropods.

Epidemiological aspects of pediculosis by Pediculus humanus capitis (Phthiraptera: Pediculidae) in Minas Gerais: a systematic review / Aspectos epidemiológicos da pediculose por Pediculus humanus capitis (Phthiraptera: Pediculidae) em Minas Gerais: uma revisão sistemática

Abstract Background Head lice, or head pediculosis, is a parasitosis considered a serious public health problem that affects mainly resource-limited countries. Objective To describe epidemiological aspects of the pediculosis capitis in Minas Gerais, in Brazil. Method This systematic review was conducted through the standards established by the Preferred Reporting Items in Systematic Reviews and Metanalyses (PRISMA). PubMed, LILACS, and SciELO databases, as well as the gray literature, were searched. Results Nine of 1,167 studies were included, published between 1988 and 2019. These studies reported a total prevalence of parasitosis that ranged from 1.4% to 57.4%. The prevalence of head lice ranged from 0.0% to 66.7% for males and 2.3% to 57.4% for females, thus being higher in black-skinned people (1.4% to 40.3%). Regarding age, the highest prevalence was 10-12 years old (45.3%). As for the characteristics of the hair, there was a greater infestation in people with long (16.0% to 79.5%), wavy (0.0% to 44.7%), dark (0.0% to 36.6%), with low capillary density (35.4%), and thick hair (39.2%). Conclusion Head pediculosis affects both sexes, different ages, and races, representing an important health problem in Minas Gerais, not only due to the presence of ectoparasite but also to the secondary complications that can be generated from this parasitism.

Resumo Introdução A pediculose de cabeça é uma parasitose considerada um sério problema de saúde pública, afetando principalmente países com recursos limitados. Objetivo Descrever os aspectos epidemiológicos da pediculose de cabeça em Minas Gerais, Brasil. Método Revisão sistemática conduzida por meio dos padrões estabelecidos pelo Preferred Reporting Items in Systematic Reviews and Metanalyses (PRISMA). Foram pesquisadas as bases de dados PubMed, LILACS e SciELO, bem como a literatura cinza. Resultados Nove de 1.167 estudos foram incluídos, publicados entre 1988 e 2019. Relatou-se uma prevalência total da parasitose que variou de 1,4% a 57,4%. Ela variou de 0,0% a 66,7% para homens e 2,3% a 57,4% para mulheres, sendo maior em pessoas de cor negra (1,4% a 40,3%). Em relação à idade, a maior prevalência foi de 10 a 12 anos (45,3%). Quanto às características dos cabelos, houve maior infestação em pessoas com cabelos longos (16,0% a 79,5%), ondulados (0,0% a 44,7%), escuros (0,0% a 36,6%), com baixa densidade capilar (35,4%) e fios grossos (39,2%). Conclusão A pediculose atinge ambos os sexos, diferentes idades e raças, representando um importante problema de saúde em Minas Gerais, não só pela presença do ectoparasita, mas também pelas complicações secundárias que podem ser geradas desse parasitismo.

Prevalence and diversity of ectoparasites in Wild Rock Pigeon (Columba livia) in Punjab region, Pakistan / Prevalência e diversidade de ectoparasitas em Wild Rock Pigeon (Columba livia) na região de Punjab, Paquistão

The current study was carried out to estimate the prevalence and diversity of ectoparasites in rock pigeons in different regions of Punjab, Pakistan. A total of 120 birds were captured from March 2017 to February 2019. The ectoparasites were collected by standard procedures and preserved in 70% ethanol containing one drop of glycerin. Data related to age, health status, sex, type of area, sampling location and season were collected using a standardized form. Ectoparasites were identified based on morphological characteristics by using identification keys. Ninety-six (80%) birds were infested with ectoparasites. A total of seven families and thirteen species of different ectoparasites were observed. Mainly, seven species of lice, two species of flies, one species of tick and three species of mites were recovered from infested birds. The female pigeons were more often infested (89.02%) than male pigeons (60.52%). The prevalence was found higher during summer (100%) as compared to other seasons. The infestation rate was higher in Industrial area (97.50%) as compared to other regions. The highest prevalence of ectoparasites (100%) was recorded from Sargodha district. There was significant (P < 0.05) variation among number of ectoparasites on wing, chest, tail and neck within age groups, seasons and ecological zones. The occurrence of parasites in relation to area, age, health status, sex and season were significant. The infestation rate of parasites in rock pigeon is high in different districts of Punjab. It is recommended that these wild birds infested with multiple species of ectoparasites could be the potential source of infestations in domesticated birds if they come in contact with them. The contact of domesticated birds should be prevented from wild birds to minimize the chance of cross species transmission of ectoparasites.(AU)

O presente estudo foi realizado para estimar a prevalência e diversidade de ectoparasitas em pombos-das-rochas em diferentes regiões de Punjab, Paquistão. Um total de 120 aves foram capturadas de março de 2017 a fevereiro de 2019. Os ectoparasitas foram coletados por procedimentos padrão e preservados em etanol 70% contendo uma gota de glicerina. Os dados relativos à idade, estado de saúde, sexo, tipo de área, local de amostragem e época do ano foram coletados em formulário padronizado. Os ectoparasitas foram identificados com base nas características morfológicas por meio de chaves de identificação. Noventa e seis (80%) aves estavam infestadas com ectoparasitas. Um total de sete famílias e treze espécies de diferentes ectoparasitas foram observados. Principalmente, sete espécies de piolhos, duas espécies de moscas, uma espécie de carrapato e três espécies de ácaros foram recuperadas de aves infestadas. Os pombos fêmeas foram infestados mais frequentemente (89,02%) do que os pombos machos (60,52%). A prevalência encontrada foi maior no verão (100%) em comparação com as outras estações. A taxa de infestação foi maior na área Industrial (97,50%) em relação às demais regiões. A maior prevalência de ectoparasitas (100%) foi registrada no distrito de Sargodha. Houve variação significativa (P <0,05) entre o número de ectoparasitas na asa, tórax, cauda e pescoço dentro das faixas etárias, estações do ano e zonas ecológicas. A ocorrência de parasitas em relação à área, idade, estado de saúde, sexo e estação do ano foi significativa. A taxa de infestação de parasitas em pombo-correio é alta em diferentes distritos de Punjab. Recomenda-se que essas aves selvagens infestadas com várias espécies de ectoparasitas possam ser a fonte potencial de infestações em aves domesticadas se entrarem em contato com elas. O contato de aves domesticadas deve ser evitado com aves selvagens para minimizar a chance de transmissão cruzada de ectoparasitas.(AU)

Prevalence and diversity of ectoparasites in Wild Rock Pigeon (Columba livia) in Punjab region, Pakistan / Prevalência e diversidade de ectoparasitas em Wild Rock Pigeon (Columba livia) na região de Punjab, Paquistão

The current study was carried out to estimate the prevalence and diversity of ectoparasites in rock pigeons in different regions of Punjab, Pakistan. A total of 120 birds were captured from March 2017 to February 2019. The ectoparasites were collected by standard procedures and preserved in 70% ethanol containing one drop of glycerin. Data related to age, health status, sex, type of area, sampling location and season were collected using a standardized form. Ectoparasites were identified based on morphological characteristics by using identification keys. Ninety-six (80%) birds were infested with ectoparasites. A total of seven families and thirteen species of different ectoparasites were observed. Mainly, seven species of lice, two species of flies, one species of tick and three species of mites were recovered from infested birds. The female pigeons were more often infested (89.02%) than male pigeons (60.52%). The prevalence was found higher during summer (100%) as compared to other seasons. The infestation rate was higher in Industrial area (97.50%) as compared to other regions. The highest prevalence of ectoparasites (100%) was recorded from Sargodha district. There was significant (P < 0.05) variation among number of ectoparasites on wing, chest, tail and neck within age groups, seasons and ecological zones. The occurrence of parasites in relation to area, age, health status, sex and season were significant. The infestation rate of parasites in rock pigeon is high in different districts of Punjab. It is recommended that these wild birds infested with multiple species of ectoparasites could be the potential source of infestations in domesticated birds if they come in contact with them. The contact of domesticated birds should be prevented from wild birds to minimize the chance of cross species transmission of ectoparasites.

O presente estudo foi realizado para estimar a prevalência e diversidade de ectoparasitas em pombos-das-rochas em diferentes regiões de Punjab, Paquistão. Um total de 120 aves foram capturadas de março de 2017 a fevereiro de 2019. Os ectoparasitas foram coletados por procedimentos padrão e preservados em etanol 70% contendo uma gota de glicerina. Os dados relativos à idade, estado de saúde, sexo, tipo de área, local de amostragem e época do ano foram coletados em formulário padronizado. Os ectoparasitas foram identificados com base nas características morfológicas por meio de chaves de identificação. Noventa e seis (80%) aves estavam infestadas com ectoparasitas. Um total de sete famílias e treze espécies de diferentes ectoparasitas foram observados. Principalmente, sete espécies de piolhos, duas espécies de moscas, uma espécie de carrapato e três espécies de ácaros foram recuperadas de aves infestadas. Os pombos fêmeas foram infestados mais frequentemente (89,02%) do que os pombos machos (60,52%). A prevalência encontrada foi maior no verão (100%) em comparação com as outras estações. A taxa de infestação foi maior na área Industrial (97,50%) em relação às demais regiões. A maior prevalência de ectoparasitas (100%) foi registrada no distrito de Sargodha. Houve variação significativa (P <0,05) entre o número de ectoparasitas na asa, tórax, cauda e pescoço dentro das faixas etárias, estações do ano e zonas ecológicas. A ocorrência de parasitas em relação à área, idade, estado de saúde, sexo e estação do ano foi significativa. A taxa de infestação de parasitas em pombo-correio é alta em diferentes distritos de Punjab. Recomenda-se que essas aves selvagens infestadas com várias espécies de ectoparasitas possam ser a fonte potencial de infestações em aves domesticadas se entrarem em contato com elas. O contato de aves domesticadas deve ser evitado com aves selvagens para minimizar a chance de transmissão cruzada de ectoparasitas.

Prevalence and diversity of ectoparasites in Wild Rock Pigeon (Columba livia) in Punjab region, Pakistan

Abstract The current study was carried out to estimate the prevalence and diversity of ectoparasites in rock pigeons in different regions of Punjab, Pakistan. A total of 120 birds were captured from March 2017 to February 2019. The ectoparasites were collected by standard procedures and preserved in 70% ethanol containing one drop of glycerin. Data related to age, health status, sex, type of area, sampling location and season were collected using a standardized form. Ectoparasites were identified based on morphological characteristics by using identification keys. Ninety-six (80%) birds were infested with ectoparasites. A total of seven families and thirteen species of different ectoparasites were observed. Mainly, seven species of lice, two species of flies, one species of tick and three species of mites were recovered from infested birds. The female pigeons were more often infested (89.02%) than male pigeons (60.52%). The prevalence was found higher during summer (100%) as compared to other seasons. The infestation rate was higher in Industrial area (97.50%) as compared to other regions. The highest prevalence of ectoparasites (100%) was recorded from Sargodha district. There was significant (P 0.05) variation among number of ectoparasites on wing, chest, tail and neck within age groups, seasons and ecological zones. The occurrence of parasites in relation to area, age, health status, sex and season were significant. The infestation rate of parasites in rock pigeon is high in different districts of Punjab. It is recommended that these wild birds infested with multiple species of ectoparasites could be the potential source of infestations in domesticated birds if they come in contact with them. The contact of domesticated birds should be prevented from wild birds to minimize the chance of cross species transmission of ectoparasites.

Resumo O presente estudo foi realizado para estimar a prevalência e diversidade de ectoparasitas em pombos-das-rochas em diferentes regiões de Punjab, Paquistão. Um total de 120 aves foram capturadas de março de 2017 a fevereiro de 2019. Os ectoparasitas foram coletados por procedimentos padrão e preservados em etanol 70% contendo uma gota de glicerina. Os dados relativos à idade, estado de saúde, sexo, tipo de área, local de amostragem e época do ano foram coletados em formulário padronizado. Os ectoparasitas foram identificados com base nas características morfológicas por meio de chaves de identificação. Noventa e seis (80%) aves estavam infestadas com ectoparasitas. Um total de sete famílias e treze espécies de diferentes ectoparasitas foram observados. Principalmente, sete espécies de piolhos, duas espécies de moscas, uma espécie de carrapato e três espécies de ácaros foram recuperadas de aves infestadas. Os pombos fêmeas foram infestados mais frequentemente (89,02%) do que os pombos machos (60,52%). A prevalência encontrada foi maior no verão (100%) em comparação com as outras estações. A taxa de infestação foi maior na área Industrial (97,50%) em relação às demais regiões. A maior prevalência de ectoparasitas (100%) foi registrada no distrito de Sargodha. Houve variação significativa (P 0,05) entre o número de ectoparasitas na asa, tórax, cauda e pescoço dentro das faixas etárias, estações do ano e zonas ecológicas. A ocorrência de parasitas em relação à área, idade, estado de saúde, sexo e estação do ano foi significativa. A taxa de infestação de parasitas em pombo-correio é alta em diferentes distritos de Punjab. Recomenda-se que essas aves selvagens infestadas com várias espécies de ectoparasitas possam ser a fonte potencial de infestações em aves domesticadas se entrarem em contato com elas. O contato de aves domesticadas deve ser evitado com aves selvagens para minimizar a chance de transmissão cruzada de ectoparasitas.

Prevalence and diversity of ectoparasites in Wild Rock Pigeon (Columba livia) in Punjab region, Pakistan / Prevalência e diversidade de ectoparasitas em Wild Rock Pigeon (Columba livia) na região de Punjab, Paquistão

Abstract The current study was carried out to estimate the prevalence and diversity of ectoparasites in rock pigeons in different regions of Punjab, Pakistan. A total of 120 birds were captured from March 2017 to February 2019. The ectoparasites were collected by standard procedures and preserved in 70% ethanol containing one drop of glycerin. Data related to age, health status, sex, type of area, sampling location and season were collected using a standardized form. Ectoparasites were identified based on morphological characteristics by using identification keys. Ninety-six (80%) birds were infested with ectoparasites. A total of seven families and thirteen species of different ectoparasites were observed. Mainly, seven species of lice, two species of flies, one species of tick and three species of mites were recovered from infested birds. The female pigeons were more often infested (89.02%) than male pigeons (60.52%). The prevalence was found higher during summer (100%) as compared to other seasons. The infestation rate was higher in Industrial area (97.50%) as compared to other regions. The highest prevalence of ectoparasites (100%) was recorded from Sargodha district. There was significant (P < 0.05) variation among number of ectoparasites on wing, chest, tail and neck within age groups, seasons and ecological zones. The occurrence of parasites in relation to area, age, health status, sex and season were significant. The infestation rate of parasites in rock pigeon is high in different districts of Punjab. It is recommended that these wild birds infested with multiple species of ectoparasites could be the potential source of infestations in domesticated birds if they come in contact with them. The contact of domesticated birds should be prevented from wild birds to minimize the chance of cross species transmission of ectoparasites.

Resumo O presente estudo foi realizado para estimar a prevalência e diversidade de ectoparasitas em pombos-das-rochas em diferentes regiões de Punjab, Paquistão. Um total de 120 aves foram capturadas de março de 2017 a fevereiro de 2019. Os ectoparasitas foram coletados por procedimentos padrão e preservados em etanol 70% contendo uma gota de glicerina. Os dados relativos à idade, estado de saúde, sexo, tipo de área, local de amostragem e época do ano foram coletados em formulário padronizado. Os ectoparasitas foram identificados com base nas características morfológicas por meio de chaves de identificação. Noventa e seis (80%) aves estavam infestadas com ectoparasitas. Um total de sete famílias e treze espécies de diferentes ectoparasitas foram observados. Principalmente, sete espécies de piolhos, duas espécies de moscas, uma espécie de carrapato e três espécies de ácaros foram recuperadas de aves infestadas. Os pombos fêmeas foram infestados mais frequentemente (89,02%) do que os pombos machos (60,52%). A prevalência encontrada foi maior no verão (100%) em comparação com as outras estações. A taxa de infestação foi maior na área Industrial (97,50%) em relação às demais regiões. A maior prevalência de ectoparasitas (100%) foi registrada no distrito de Sargodha. Houve variação significativa (P <0,05) entre o número de ectoparasitas na asa, tórax, cauda e pescoço dentro das faixas etárias, estações do ano e zonas ecológicas. A ocorrência de parasitas em relação à área, idade, estado de saúde, sexo e estação do ano foi significativa. A taxa de infestação de parasitas em pombo-correio é alta em diferentes distritos de Punjab. Recomenda-se que essas aves selvagens infestadas com várias espécies de ectoparasitas possam ser a fonte potencial de infestações em aves domesticadas se entrarem em contato com elas. O contato de aves domesticadas deve ser evitado com aves selvagens para minimizar a chance de transmissão cruzada de ectoparasitas.

Why vaccines fail against Piscirickettsiosis in farmed salmon and trout and how to avoid it: A review.

Piscirickettsiosis is the most severe, persistent, and damaging disease that has affected the Chilean salmon industry since its origins in the 1980s. As a preventive strategy for this disease, different vaccines have been developed and used over the last 30 years. However, vaccinated salmon and trout frequently die in the sea cages and the use of antibiotics is still high demonstrating the low efficiency of the available vaccines. The reasons why the vaccines fail so often are still debated, but it could involve different extrinsic and intrinsic factors. Among the extrinsic factors, mainly associated with chronic stress, we can distinguish: 1) biotic including coinfection with sea lice, sealions attacks or harmful algal blooms; 2) abiotic including low oxygen or high temperature; and 3) farm-management factors including overcrowding or chemical delousing treatments. Among the intrinsic factors, we can distinguish: 1) fish-related factors including host's genetic variability (species, population and individual), sex or age; 2) pathogen-related factors including their variability and ability to evade host immune responses; and 3) vaccine-related factors including low immunogenicity and poor matches with the circulating pathogen strain. Based on the available evidence, in order to improve the development and the efficacy of vaccines against P. salmonis we recommend: a) Do not perform efficacy evaluations by intraperitoneal injection of pathogens because they generate an artificial protective immune response, instead cohabitation or immersion challenges must be used; b) Evaluate the diversity of pathogen strains in the field and ensure a good antigenic match with the vaccines; c) Investigate whether host genetic diversity could be improved, e.g. through selection, in favor of better and longer responses to vaccination; d) To reduce the stressful effects at the cage level, controlling the co-infection of pathogens and avoiding fish overcrowding. To date, we do not know the immunological mechanisms by which the vaccines against P. salmonis may or may not generate protection. More studies are required to identify what type of response, cellular or molecular, is required to develop effective vaccines.

Commercial Vaccines Do Not Confer Protection against Two Genogroups of Piscirickettsia salmonis, LF-89 and EM-90, in Atlantic Salmon.

In Atlantic salmon, vaccines have failed to control and prevent Piscirickettsiosis, for reasons that remain elusive. In this study, we report the efficacy of two commercial vaccines developed with the Piscirickettsia salmonis isolates AL100005 and AL 20542 against another two genogroups which are considered highly and ubiquitously prevalent in Chile: LF-89 and EM-90. Two cohabitation trials were performed to mimic field conditions and vaccine performance: (1) post-smolt fish were challenged with a single infection of LF-89, (2) adults were coinfected with EM-90, and a low level coinfection of sea lice. In the first trial, the vaccine delayed smolt mortalities by two days; however, unvaccinated and vaccinated fish did not show significant differences in survival (unvaccinated: 60.3%, vaccinated: 56.7%; p = 0.28). In the second trial, mortality started three days later for vaccinated fish than unvaccinated fish. However, unvaccinated and vaccinated fish did not show significant differences in survival (unvaccinated: 64.6%, vaccinated: 60.2%, p = 0.58). Thus, we found no evidence that the evaluated vaccines confer effective protection against the genogroups LF-89 and EM-90 of P. salmonis with estimated relative survival proportions (RPSs) of -9% and -12%, respectively. More studies are necessary to evaluate whether pathogen heterogeneity is a key determinant of the lack of vaccine efficacy against P. salmonis.