-
Parasites & Vectors May 2024The chicken body louse is an obligate ectoparasite of domestic chickens. Chicken body lice feed on feathers, and infestation with this louse is linked to decreases in...
BACKGROUND
The chicken body louse is an obligate ectoparasite of domestic chickens. Chicken body lice feed on feathers, and infestation with this louse is linked to decreases in egg production, hen weight, and feed conversion efficiency. However, it is unknown how chicken body lice impact egg-laying chickens in cage-free environments. Welfare and behavior metrics were collected from flocks of egg-laying chickens either infested with chicken body lice or left uninfested.
METHODS
In two trials, two flocks of cage-free commercial egg-laying chickens were infested with chicken body lice or maintained as uninfested controls. At three timepoints, behavior and welfare of all chickens was measured. On-animal sensors were used to quantify pecking, preening, and dustbathing behavior. Other animal-based welfare metrics included recording comb wounds and skin lesions.
RESULTS
Birds infested with chicken body lice exhibited significantly more preening behaviors than uninfested birds, even at low louse levels. Moderate or severe skin lesions were detected on birds that were moderately infested with chicken body lice while skin lesions were never detected on uninfested birds.
CONCLUSIONS
The welfare of chickens was impacted by the chicken body louse, a chewing louse that primarily feather feeds. Evidence of skin lesions on infested birds suggests that lice may cause more damage to birds than previously thought, and further evaluation of louse economic damage is necessary.
Topics: Animals; Chickens; Poultry Diseases; Animal Welfare; Housing, Animal; Female; Behavior, Animal; Amblycera; Feathers; Lice Infestations
PubMed: 38745229
DOI: 10.1186/s13071-024-06313-6 -
Frontiers in Genetics 2024Sea louse () infestation of Atlantic salmon () is a significant challenge in aquaculture. Over the years, this parasite has developed immunity to medicinal control...
Sea louse () infestation of Atlantic salmon () is a significant challenge in aquaculture. Over the years, this parasite has developed immunity to medicinal control compounds, and non-medicinal control methods have been proven to be stressful, hence the need to study the genomic architecture of salmon resistance to sea lice. Thus, this research used whole-genome sequence (WGS) data to study the genetic basis of the trait since most research using fewer SNPs did not identify significant quantitative trait loci. Mowi Genetics AS provided the genotype (50 k SNPs) and phenotype data for this research after conducting a sea lice challenge test on 3,185 salmon smolts belonging to 191 full-sib families. The 50 k SNP genotype was imputed to WGS using the information from 197 closely related individuals with sequence data. The WGS and 50 k SNPs of the challenged population were then used to estimate genetic parameters, perform a genome-wide association study (GWAS), predict genomic breeding values, and estimate its accuracy for host resistance to sea lice. The heritability of host resistance to sea lice was estimated to be 0.21 and 0.22, while the accuracy of genomic prediction was estimated to be 0.65 and 0.64 for array and WGS data, respectively. In addition, the association test using both array and WGS data did not identify any marker associated with sea lice resistance at the genome-wide level. We conclude that sea lice resistance is a polygenic trait that is moderately heritable. The genomic predictions using medium-density SNP genotyping array were equally good or better than those based on WGS data.
PubMed: 38706794
DOI: 10.3389/fgene.2024.1381333 -
International Journal For Parasitology.... Aug 2024Martin, Keatley & Ash n. sp. from the western ground parrot North, 1911 (Psittaculidae) is proposed based on combined evidence from morphology and mitochondrial DNA....
Martin, Keatley & Ash n. sp. from the western ground parrot North, 1911 (Psittaculidae) is proposed based on combined evidence from morphology and mitochondrial DNA. Phylogenetically, the new species is closest to its two known congeners from Western Australia: . Price, Johnson & Palma, 2008 from Bourke's parrot (Gould, 1841) and the scarlet-chested parrot (Gould, 1841), and . Guimarães, 1985 from the Australian ringneck parrot (Shaw, 1805). Morphologically it is distinguishable by abdominal chaetotaxy and characters of the male genitalia, and is most similar to . and . Guimarães, 1985; the latter has no representative sequence data. is the eleventh species of its genus and the only metazoan parasite known from . , which is among Australia's most endangered vertebrates. The new louse is apparently restricted to . and is therefore co-endangered, facing at least the same likelihood of extinction as its host. We recommend ongoing translocation and field monitoring efforts for . include monitoring but not treatment for lice infestations in otherwise healthy individuals, and that the care management plan for captive . considers that . is similarly imperilled.
PubMed: 38655449
DOI: 10.1016/j.ijppaw.2024.100931 -
International Journal For Parasitology Apr 2024Parasitic salmon lice (Lepeophtheirus salmonis) are a constraint to the sustainable growth of salmonids in open net pens, and this issue has caused production to level...
Parasitic salmon lice (Lepeophtheirus salmonis) are a constraint to the sustainable growth of salmonids in open net pens, and this issue has caused production to level off in recent years in the most aquaculture-intensive areas of Norway. The maximum allowed biomass at a regional level is regulated by using the so-called "traffic light" system, where salmon louse-induced mortality of migrating wild salmon post-smolts is evaluated against set targets. As a case study, we have investigated how a specific aquaculture-intensive area can reduce its louse levels sufficiently to achieve a low impact on wild salmon. Analyses of the output from a virtual post-smolt model that uses data on the reported number of salmon lice in fish farms as key input data and estimates the salmon louse-induced mortality of wild out-migrating Atlantic salmon post-smolts, suggested that female louse abundance on the local farms must be halved in spring to reach the goal implied by the traffic light system. The outcome of a modelling scenario simulating a proposed new plan for coordinated production and fallowing proved beneficial, with an overall reduction in louse infestations and treatment efforts. The interannual variability in louse abundance in spring, however, increased for this scenario, implying unacceptably high louse abundance when many farms were in their second production year. We then combined the scenario with coordinated production with other louse control measures. Only measures that reduced the density of farmed salmonids in open cages in the study area resulted in reductions in salmon louse infestations to acceptable levels. This could be achieved either by stocking with larger fish to reduce exposure time or by reducing fish numbers, e.g. by producing in closed units.
PubMed: 38609075
DOI: 10.1016/j.ijpara.2024.04.003 -
The Pan African Medical Journal 2024
Topics: Animals; Humans; Pediculus; Eyelashes; Lice Infestations
PubMed: 38558554
DOI: 10.11604/pamj.2024.47.29.42559 -
Reviews in Aquaculture Mar 2023Disease and parasitism cause major welfare, environmental and economic concerns for global aquaculture. In this review, we examine the status and potential of... (Review)
Review
Disease and parasitism cause major welfare, environmental and economic concerns for global aquaculture. In this review, we examine the status and potential of technologies that exploit genetic variation in host resistance to tackle this problem. We argue that there is an urgent need to improve understanding of the genetic mechanisms involved, leading to the development of tools that can be applied to boost host resistance and reduce the disease burden. We draw on two pressing global disease problems as case studies-sea lice infestations in salmonids and white spot syndrome in shrimp. We review how the latest genetic technologies can be capitalised upon to determine the mechanisms underlying inter- and intra-species variation in pathogen/parasite resistance, and how the derived knowledge could be applied to boost disease resistance using selective breeding, gene editing and/or with targeted feed treatments and vaccines. Gene editing brings novel opportunities, but also implementation and dissemination challenges, and necessitates new protocols to integrate the technology into aquaculture breeding programmes. There is also an ongoing need to minimise risks of disease agents evolving to overcome genetic improvements to host resistance, and insights from epidemiological and evolutionary models of pathogen infestation in wild and cultured host populations are explored. Ethical issues around the different approaches for achieving genetic resistance are discussed. Application of genetic technologies and approaches has potential to improve fundamental knowledge of mechanisms affecting genetic resistance and provide effective pathways for implementation that could lead to more resistant aquaculture stocks, transforming global aquaculture.
PubMed: 38504717
DOI: 10.1111/raq.12733 -
Veterinary Medicine and Science May 2024Ectoparasites of dogs and cats are implicated to be responsible for life-threatening anaemia, allergic dermatitis and pruritic and non-pruritic skin disorders. In...
BACKGROUND
Ectoparasites of dogs and cats are implicated to be responsible for life-threatening anaemia, allergic dermatitis and pruritic and non-pruritic skin disorders. In Ethiopia, few studies have been conducted on the arthropods of dogs and cats.
OBJECTIVES
In order to shed light on some of these aspects, a survey was conducted to investigate the presence of ectoparasites in dogs and cats living in sympatry in the urban and rural areas of Gamo Zone, Ethiopia.
METHODS
A total of 297 dogs and 110 cats were examined for ectoparasites, and questionnaires were employed to obtain information concerning owner's knowledge about arthropods and vector-borne diseases (VBDs).
RESULTS
The overall prevalence of ticks, fleas and lice in dogs was 36.7%, 69.7% and 4.7%, respectively. Similarly, on cats, an overall prevalence of 2.7% ticks and 21.8% fleas was recorded. On dogs, fleas (Ctenocephalides felis 69.4%, Echidnophaga gallinacea 1.3%, Ctenocephalides canis 1.0% and Pulex irritans 0.3%), ticks (Amblyomma variegatum 22.9%, Rhipicephalus sanguineus 14.1%, Haemaphysalis leachi 8.8%, Rhipicephalus praetextatus 4.0% and Rhipicephalus pulchellus 3.4%) and lice (Heterodoxus spiniger 4.0% and Trichodectes canis 0.7%) were identified. Likewise, on cats, fleas (C. felis [15.5%] and E. gallinacea [7.3%]) and ticks (H. leachi [2.7%]) were identified. The abundance of C. felis was significantly higher (p < 0.001) on dogs, whereas in cats, the abundance of E. gallinacea was significantly higher (p = 0.002) than the other ectoparasites. On dogs, a significantly higher prevalence of Rh. sanguineus was recorded in urban areas (<0.001) and on dogs which live in indoor environments (p = 0.003) than on dogs which live in other environments. On the other hand, the prevalence of A. variegatum in rural areas and midland agroecology was significantly higher (p < 0.001). The prevalence of H. leachi was significantly higher in midland (p < 0.001) and on adult dogs (p = 0.001). Overall, fleas were more prevalent in rural (p = 0.029) than in urban areas, and female dogs were with higher infestation than the male (p = 0.047) dogs; C. felis was prevalent in female (p = 0.038) dogs than males. Overall, 88.3% owners in the study area had no knowledge about ectoparasites and VBDs of dogs and cats. Majority of the owners (64.8%) attest that they had never visited veterinary clinics.
CONCLUSIONS
In conclusion, the data presented in the present study provide additional knowledge on the importance of ectoparasites of dogs and cats and are believed to contribute in awareness creation and strengthening of veterinary services of dogs and cats of the study area.
Topics: Animals; Dogs; Cats; Male; Female; Cat Diseases; Ethiopia; Sympatry; Dog Diseases; Flea Infestations; Siphonaptera; Ticks; Felis; Surveys and Questionnaires
PubMed: 38504631
DOI: 10.1002/vms3.1413 -
Actas Dermo-sifiliograficas May 2024Sexually transmitted infections are communicable diseases where the pathogen is transmitted through sexual contact. The Sexually Transmitted Infections Working Group of...
[Translated article] Spanish Academy of Dermatology and Venereology (AEDV) expert recommendations for the management of sexual transmitted parasitosis. Scabies, and pediculosis pubis.
Sexually transmitted infections are communicable diseases where the pathogen is transmitted through sexual contact. The Sexually Transmitted Infections Working Group of the Spanish Academy of Dermatology and Venereology (AEDV) is engaged in the drafting of documents to guide dermatologists and health care personnel who treat Spanish patients with these infections. This document analyzes the epidemiological, clinical, therapeutic, and control characteristics of 2 sexually transmitted parasitosis: scabies due to Sarcoptes scabiei var. hominis, and pubic pediculosis due to Phthirus pubis. Both parasitoses share a sort of mixed spread through sexual and community transmission regardless of the route through which the infection was initially acquired. This specific feature creates particularities in the management and control of the infestation.
Topics: Humans; Scabies; Lice Infestations; Female; Male; Sexually Transmitted Diseases; Spain; Animals; Phthirus
PubMed: 38479688
DOI: 10.1016/j.ad.2024.03.016 -
Animals : An Open Access Journal From... Mar 2024Sheep ectoparasites such as chewing lice, fleas and ticks are serious constraints to sheep productivity and are the cause of skin lesions in animals that decrease their...
Sheep ectoparasites such as chewing lice, fleas and ticks are serious constraints to sheep productivity and are the cause of skin lesions in animals that decrease their market value. This study aims at investigating the ectoparasite fauna infesting small ruminants in the district of Sidi Bouzid (central Tunisia). A total of 1243 Barbarine and Queue Fine de l'Ouest (QFO) sheep were examined every two months for one year. Of the total animals examined, 74 were infested by at least 1 parasite group (5.95%). Three ectoparasite groups were identified as (0.48%; 6/1243), ticks (5.3%; = 66/1243) and one specimen of (0.08%; = 1/1243). The most abundant tick among the 358 specimens was sensu lato ( = 337; 94.1%), followed by ( = 7/358; 1.9%), ( = 7/358; 1.9%), ( = 5/358; 1.4%) and only two specimens of ( = 2/358; 0.55%). The sheep herds showed low infestation prevalence by ectoparasite over the year, with a significant difference according to the seasons ( < 0.05). A higher infestation prevalence was recorded in March (14.36%). Barbarine sheep breed showed significantly higher infestation prevalence (16.8%) compared to QFO (0.8%) ( < 0.01). There were no differences in infestation prevalence according to sex of the animal or age groups. Knowledge of the ectoparasite population harboured by sheep, its activity dynamics and risk factors is required to develop effective ectoparasite control options. The low prevalence of ectoparasite infestation in sheep reported here may be due to possible genetic resistance or simply to successful hygiene measures implemented by farmers.
PubMed: 38473186
DOI: 10.3390/ani14050801 -
Turkiye Parazitolojii Dergisi Mar 2024The purpose of this study was to investigate the prevalence of intestinal parasites and head lice in primary school-aged children and to determine a possible...
OBJECTIVE
The purpose of this study was to investigate the prevalence of intestinal parasites and head lice in primary school-aged children and to determine a possible relationship between the co-occurrence of ecto-endoparasites.
METHODS
The study were conducted in three schools in the center of Sivas: Sivas Karşıyaka Primary School, Kılavuz İMKB Primary School, and Karşıyaka 27 June Middle School. The presence of head lice and intestinal parasites was investigated in a total of 563 children aged 6 to 17, with 294 girls and 269 boys. Classroom teachers and students were provided with information about intestinal parasites, head lice, and methods of transmission and prevention, and a questionnaire was administered. During the head lice examination, students were inspected with a comb, and samples with nits were examined under a microscope in the laboratory. Cellophane tape and stool samples obtained from the participants were examined on the same day using the native-lugol, flotation, and trichrome staining methods under a light microscope (x10, x40, x100).
RESULTS
Five hundred sixty-three children were evaluated for head lice and 15 (2.6%) were found to be positive. During the examination, only nits were found in 11 students (1.9%), and both adult lice and nymphs were seen in 4 students (0.7%). Head lice were found positive in 2 out of 269 boys (0.7%), while 13 out of 294 girls (4.2%) positive (p<0.05). As a result of stool examination in children, was found in 11 (1.95%), in 4 (0.71%), sp. in 14 (2.48%), in 8 (1.42%) and spp. in 2 (0.35%). Head lice infestation and spp. were found to coexist in 2 (0.35%) children.
CONCLUSION
In conclusion, although there has been a noticeable decrease in head lice and intestinal parasites among primary school-aged children in Sivas province, these conditions are still present, as evidenced by previous studies conducted in our region.
Topics: Adult; Male; Child; Female; Animals; Humans; Pediculus; Lice Infestations; Parasites; Intestinal Diseases, Parasitic; Schools
PubMed: 38449365
DOI: 10.4274/tpd.galenos.2023.04796