Search Results (12)

(1) Background: The common buzzard (Buteo buteo) is the most widespread raptor in Romania. This study aimed to assess the occurrence of chewing louse species and the factors influencing the epidemiology of louse infestation in the national bird populations. (2) Methods: Between 2012 and 2025, a total of 131 buzzards were collected from all over Romania, which were either roadkilled or died due to health issues. These birds were parasitologically examined, the gathered lice were identified, and epidemiological parameters were determined. (3) Results: The overall prevalence of louse infestation was 77.9%, with 4389 specimens collected. Five species were identified: Degeeriella fulva (55.7%), Craspedorrhynchus platystomus (37.4%), Colpocephalum nanum (42.0%), Colpocephalum turbinatum (7.6%), and Laemobothrion maximum (2.3%). Among the factors influencing the evolution of louse infestations, birds’ age statistically significantly affected only the mean intensity (48.0 in subadults and 28.6 in adults, p < 0.001). Combined origin and season through temperatures and relative humidity also influenced the mean intensity of infestations. Sex-ratio and nymph-to-female ratio were, in the majority, female-biased and nymph-biased. (4) Conclusions: Lice infestation patterns of common buzzards are shaped more commonly by environmental and biogeographic context than by host sex, with temperature, humidity gradients, and region of origin primarily influencing mean intensity rather than prevalence. In addition, sex ratios were consistently female-biased across all lice species, and nymph-to-female ratios suggested contrasting demographic trajectories among taxa, with evidence of expanding infrapopulations in some species and more senescent structures in others. Full article

Background: Ectoparasitic insects (fleas and sucking lice) on rodents can serve as vectors of some zoonotic diseases. Objective: To investigate the insect infestation and distribution on white-footed Indochinese rats (Rattus nitidus) in southwest China, a focus of zoonotic diseases. Methods: Field investigations were conducted at 116 survey sites between 2000 and 2024. Insects were identified under a microscope, and a series of calculations was conducted. Results: From 836 R. nitidus rat hosts, 3322 insects were identified as 24 species, including eight vector species. Fleas had more species (22) and fewer individuals (539) than sucking lice (two species with 2783 individuals). Male and adult hosts had higher insect infestations than females and juveniles (p < 0.05), and insect infestations varied in different environments. The insect spatial coefficients were higher than the critical values for determining aggregated distribution. The association coefficient between fleas and lice was V = 0.07 (p < 0.05). Conclusions: Rattus nitidus is susceptible to insect infestation, with the coexistence of multiple vector species. Fleas have much higher species diversity than sucking lice. Insect infestations exhibit sex and age biases of hosts as well as environmental heterogeneity. Fleas and lice are of aggregated and mutually independent distribution on R. nitidus. Multiple vector species on R. nitidus would probably increase the potential risk of transmission and focus persistence of related zoonotic diseases in southwest China. Full article

Chewing lice are among the most significant ectoparasites affecting poultry, causing irritation, anemia, and reduced productivity, thereby posing economic and welfare challenges for poultry farmers. Their impact is particularly pronounced in sub-Saharan Africa, where poultry production is predominantly free-range with limited biosecurity, which increases exposure to infestation. This review was conducted to determine the epidemiology of chewing lice species of poultry in sub-Saharan African countries. A search of peer-reviewed literature on the epidemiology of chewing lice species of poultry was conducted on four electronic databases from 1990 to 2024. Nineteen species of chewing lice, namely Menacanthus stramineus, Menacanthus cornutus, Menacanthus pallidulus, Menopon gallinae, Lipeurus caponis, Lipeurus tropicalis, Gallacanthus cornutus, Goniocotes gigas, Goniocotes gallinae, Goniocotes hologaster, Goniodes gigas, Goniodes meleagridis, Goniodes gallinae, Goniodes dissimilis, Cuclotogaster heterographus, Stenocrotaphus gigas, Columbicola columbae, Chelopistes meleagridis, and Amyrsidea powelli, were reported from six poultry species distributed across ten African countries. The identification of the chewing lice species was primarily based on microscopic examination of the morphological features, which resulted in the exclusion of some studies that failed to identify lice to the species level. Poultry species infested included chickens (Gallus gallus domesticus), turkeys (Meleagris gallopavo), ducks (Anas platyrhynchos), guinea fowls (Numida meleagridis), pigeons (Columba livia), and geese (Anser cygnoides). Nigeria recorded the highest number of chewing lice species. The genus Goniodes showed the highest species diversity, and M. stramineus was the most predominant species, reported in nine of the ten reviewed countries. Infestations were mostly reported in chickens compared to other poultry species, and the prevalence ranged from 1.28% in chickens in Ethiopia to 100% in chickens from Zimbabwe. Results from this review provide valuable insights into the species diversity and regional distribution patterns of chewing lice fauna, highlighting their dispersion and host associations. The review will serve as a valuable resource in the design of effective and sustainable prevention and control strategies of chewing lice, especially in free-range chickens reared by resource-poor communities in sub-Saharan Africa. Full article

Mitochondrial (mt) genome fragmentation has been discovered in all five parvorders of parasitic lice (Phthiraptera). To explore whether minichromosomal characters derived from mt genome fragmentation are informative for phylogenetic studies, we sequenced the mt genomes of 17 species of bird lice in Menoponidae and Laemobothriidae (Amblycera). Four species of Menoponidae (Actornithophilus sp. 1 ex [pied oystercatcher], Act. sp. 2 ex [masked lapwing], Austromenopon sp. 2 ex [sooty tern and crested tern], Myr. sp. 1 ex [satin bowerbird]) have fragmented mt genomes, whereas the other 13 species retain the single-chromosome mt genomes. The two Actornithophilus species have five and six mt minichromosomes, respectively. Aus. sp. 2 ex [sooty tern and crested tern] has two mt minichromosomes, in contrast to Aus. sp. 1 ex [sooty shearwater], which has a single mt chromosome. Myr. sp. 1 ex [satin bowerbird] has four mt minichromosomes. When mapped on the phylogeny of Menoponidae and Laemobothriidae, it is evident that mt genome fragmentation has occurred multiple times independently among Menoponidae and Laemobothriidae species. We found derived mt minichromosomal characters shared between Myrsidea species, between Actornithophilus species, and between and among different ischnoceran genera, respectively. We conclude that while mt genome fragmentation as a general feature does not unite all the parasitic lice that have this feature, each independent mt genome fragmentation event does produce minichromosomal characters that can be informative for phylogenetic studies of parasitic lice at different taxonomic levels. Full article

Patterns of prevalence in chewing lice (Phthiraptera) on wild birds are poorly known, as are the underlying factors that influence these patterns. Here, we analyze a data set consisting of published prevalence data of lice on shorebirds, as well as new prevalence data from shorebirds examined in Australia, Canada, China, Japan, and Sweden between 2007 and 2020. In total, prevalence data from 10 genera of lice from over 110 host species were included, including all major families of shorebirds. Using a generalized linear mixed model, we examine how the prevalence of lice of different genera varies between different sets of birds, focusing on two factors associated with migration (migration length and migration route). We found that host body size does not influence prevalence of lice in the Charadriiformes for any of the four most common and widely distributed louse genera (Actornithophilus, Austromenopon, Quadraceps, and Saemundssonia). Moreover, neither of the two migration variables showed any statistically significant correlations with prevalence, except for the genus Saemundssonia in which the prevalence of lice on short-distance migrants was significantly higher than on intermediate- and long-distance migrants. We also present 15 new records of chewing lice for China and 12 for Australia. Full article

We documented the presence/absence of the eggs of Trochiloecetes, Trochiliphagus, and Leremenopon lice on over 50,000 hummingbird specimens (representing 348 species plus 247 additional subspecies) in four museums in the USA. (i) We provide sample estimates of infestation prevalence. (ii) Sample estimates of parasite genus richness increased with increasing host sample size. (iii) Host body mass did not correlate with parasite genus richness, even when controlled for sample size effects. (iv) The prevalence of Trochiliphagus and Trochiloecetes infestations did not correlate with host body mass, while the prevalence of Leremenopon exhibited a marginally significant positive correlation with host body mass. (v) The prevalence of Trochiliphagus and Leremenopon infestations correlated strongly and positively across host taxa (i.e., species or subspecies). (vi) The co-occurrence of Trochiliphagus and Trochiloecetes within the few largest host samples—i.e., within particular host taxa—was significantly more frequent than expected by chance. This latter association might indicate a true ecological relationship or, alternatively, might have emerged as an artifact of our sampling method. (vii) We found no relationship between host sexual size dimorphism and the prevalence of any of the three louse genera, contrary to the interspecific prediction of the Hamilton–Zuk hypothesis. Full article

Next-generation sequencing technologies are revolutionizing the fields of genomics, phylogenetics, and population genetics. These new genomic approaches have been extensively applied to a major group of parasites, the lice (Insecta: Phthiraptera) of birds and mammals. Two louse genomes have been assembled and annotated to date, and these have opened up new resources for the study of louse biology. Whole genome sequencing has been used to assemble large phylogenomic datasets for lice, incorporating sequences of thousands of genes. These datasets have provided highly supported trees at all taxonomic levels, ranging from relationships among the major groups of lice to those among closely related species. Such approaches have also been applied at the population scale in lice, revealing patterns of population subdivision and inbreeding. Finally, whole genome sequence datasets can also be used for additional study beyond that of the louse nuclear genome, such as in the study of mitochondrial genome fragmentation or endosymbiont function. Full article

Animal mitochondrial (mt) genomes are typically double-strand circular DNA molecules, but diverse structural variations have been widely found in multiple groups. In parasitic lice (Phthiraptera), the structure of mt genomes varies remarkably across all five suborders. In this study, we reported the complete mt genome of a chicken body louse, Menacanthus cornutus, which has a typical single circular mt chromosome and drastic mt gene rearrangements. This mt genome is 15,693 bp in length, consisting of 13 protein-coding genes, 23 tRNA genes, 2 rRNA genes, and a control region. A comparison with a typical insect mt genome suggested that two highly similar trnM are present in the mt genome of M. cornutus. Moreover, almost every single gene was rearranged, and over half of mt genes were inverted. Phylogenetic analyses inferred from the mt genome sequences supported the monophyly and position of Amblycera. Mapped over the phylogenetic relationships of Amblycera, we identified two inversion events for the conserved gene blocks in Boopidae and Menoponidae. The inverted ND4L-ND4 was likely a synapomorphic rearrangement in Menoponidae. Our study demonstrated the importance of sequencing mt genomes for additional taxa to uncover the mechanism underlying the structural evolution of the mt genome in parasitic lice. Full article

The diversity and spatial distribution of ectoparasites of a large colony of white stork Ciconia ciconia at Dréan, in north-eastern Algeria, were investigated during two consecutive breeding seasons. The results indicated that nestlings were infested by the following four louse species: Colpocephalum zebra (Burmeister, 1838), Neophilopterus incompletus (Denny, 1842), Ardeicola ciconiae (Linnaeus, 1758), and Ciconiphilus quadripustulatus (Burmeister, 1838). Overall, the distribution of chewing lice exhibited a clustered distribution, with C. zebra being the most frequent species, with a prevalence of 39.6% and 41.0% in 2011 and 2012, respectively. Our results also suggested niche partitioning among the four louse species within the host’s body parts. A generalized additive model indicated that size, sex, and year influenced the abundance of ectoparasites; the abundance of chewing lice increased with the size of the host and was greater in females, as well as in the first year of study. Further studies are needed to explore the spatio-temporal variability in white storks’ lice infestations. Full article

Insects are the most evolutionarily and ecologically successful group of living animals, being present in almost all possible mainland habitats; however, they are virtually absent in the ocean, which constitutes more than 99% of the Earth’s biosphere. Only a few insect species can be found in the sea but they remain at the surface, in salt marshes, estuaries, or shallow waters. Remarkably, a group of 13 species manages to endure long immersion periods in the open sea, as well as deep dives, i.e., seal lice. Sucking lice (Phthiraptera: Anoplura) are ectoparasites of mammals, living while attached to the hosts’ skin, into their fur, or among their hairs. Among them, the family Echinophthiriidae is peculiar because it infests amphibious hosts, such as pinnipeds and otters, who make deep dives and spend from weeks to months in the open sea. During the evolutionary transition of pinnipeds from land to the ocean, echinophthiriid lice had to manage the gradual change to an amphibian lifestyle along with their hosts, some of which may spend more than 80% of the time submerged and performing extreme dives, some beyond 2000 m under the surface. These obligate and permanent ectoparasites have adapted to cope with hypoxia, high salinity, low temperature, and, in particular, conditions of huge hydrostatic pressures. We will discuss some of these adaptations allowing seal lice to cope with their hosts’ amphibious habits and how they can help us understand why insects are so rare in the ocean. Full article

South Texas is a highly variable region encompassing multiple habitat types and harboring a wide diversity of organisms. However, the parasite fauna in this region is poorly known, especially for avian ectoparasites such as lice. To better understand avian louse diversity and host associations in South Texas, we examined a total of 507 birds for chewing lice. Lice were morphologically identified to genus and phylogenetic analysis was performed using one mitochondrial (COI) and two nuclear (18S rRNA and EF-1α) genes. Of the birds examined, 69 (13.5%) were parasitized by lice resulting in a total of 63 host associations across 45 bird species, 29 of which were previously unrecorded. The predominant taxa encountered during this study included two of the most diverse louse genera, Myrsidea and Brueelia. Molecular analyses revealed 21 distinct genetic lineages, 17 of which are associated with novel host associations and may represent new species. This study represents the first extensive examination of avian louse host associations and relationships in Texas and reveals that there is still much to be learned about ectoparasite diversity in the New World. Full article

When a species colonizes a new area, it has the potential to bring with it an array of smaller-bodied symbionts. Rock Pigeons (Columba livia Gmelin) have colonized most of Canada and are found in almost every urban center. In its native range, C. livia hosts more than a dozen species of ectosymbiotic arthropods, and some of these lice and mites have been reported from Rock Pigeons in the United States. Despite being so abundant and widely distributed, there are only scattered host-symbiont records for rock pigeons in Canada. Here we sample Rock Pigeons from seven locations across Canada from the west to east (a distance of > 4000 km) to increase our knowledge of the distribution of their ectosymbionts. Additionally, because ectosymbiont abundance can be affected by temperature and humidity, we looked at meteorological variables for each location to assess whether they were correlated with ectosymbiont assemblage structure. We found eight species of mites associated with different parts of the host’s integument: the feather dwelling mites Falculifer rostratus (Buchholz), Pterophagus columbae (Sugimoto) and Diplaegidia columbae (Buchholz); the skin mites: Harpyrhynchoides gallowayi Bochkov, OConnor and Klompen, H. columbae (Fain), and Ornithocheyletia hallae Smiley; and the nasal mites Tinaminyssus melloi (Castro) and T. columbae (Crossley). We also found five species of lice: Columbicola columbae (Linnaeus), Campanulotes compar (Burmeister), Coloceras tovornikae Tendeiro, Hohorstiella lata Piaget, and Bonomiella columbae Emerson. All 13 ectosymbiont species were found in the two coastal locations of Vancouver (British Columbia) and Halifax (Nova Scotia). The symbiont species found in all sampling locations were the mites O. hallae, H. gallowayi, T. melloi and T. columbae, and the lice Colu. columbae and Camp. compar. Three local meteorological variables were significantly correlated with mite assemblage structure: annual minimum and maximum temperatures and maximum humidity in the month the pigeon was collected. Two local meteorological variables, annual maximum and average temperatures, were significantly correlated with louse assemblages. Our results suggest that milder climatic conditions may affect richness and assemblage structure of ectosymbiont assemblages associated with Rock Pigeons in Canada. Full article