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Studying teratological abnormalities in ticks are taxonomically important because this poorly understood biological phenomenon causes difficulties in tick’s identification. Globally, reports regarding these abnormalities in ticks, reasons of their causes and their impacts are scarce. According to the available published data, there are no studies regarding teratological abnormalities in ticks from Pakistan. Herein, ticks examined for these abnormalities were museum deposited, collected from buffalos, cattle, camels, goats and sheep in 17 districts of Pakistan during 2017–2023. The abnormalities were observed in 88 out of 3279 (2.68%) ticks, representing eight ixodid species (Rhipicephalus microplus, Rhipicephalus turanicus, Rhipicephalus haemaphysaloides, Haemaphysalis bispinosa, Haemaphysalis montgomeryi, Hyalomma anatolicum, Hyalomma scupense, Hyalomma dromedarii). Among abnormal ticks, 67 abnormalities were characterized as local, 12 as general and nine as a combination of both. Local abnormalities were observed in the scutum, palpal segments, anal aperture, spiracular plates, ventral plates, caudal appendage, festoons and posterior grooves. Also, the constrictions and excavations of body parts were observed. General abnormalities included irregular idiosoma and lateral idiosomal bifurcation. This study, for the first time, highlights the diversity of teratological abnormalities in Pakistani ticks, and are reported in in Hy. anatolicum, Ha. bispinosa and Ha. montgomeryi for the first time. [ABSTRACT FROM AUTHOR]

Globally, the prevalence of Rhipicephalus microplus resistance to various acaricides has increased, and there is a need for the identification of molecular markers that can predict phenotypic resistance. These markers could serve as alternatives to the larval packet test (LPT), enabling rapid and accurate monitoring of resistance in these ticks against multiple acaricides. However, many of the historically identified markers are present in isolates from specific countries and their role in acaricide resistance remains unclear. This study aimed to assess these mutations by sequencing genomic regions encoding proteins historically associated with acaricide target site insensitivity and increased acaricide detoxification and comparing resistant and susceptible isolates from eight different countries. Employing a novel multiplex PCR setup developed during the study, the coding regions of 11 acaricide-resistant targets were amplified and sequenced across 37 R. microplus isolates from different locations. The identified mutations, both previously reported and novel, were compared between acaricide-susceptible and acaricide-resistant isolates, phenotypically characterized using the larval packet test or larval immersion test across five acaricide classes. Genotypes were then correlated with available phenotypes, and protein modelling of novel nonsynonymous mutations was conducted to assess their potential impact on acaricide resistance. Previously reported resistance-associated mutations were detected, some of which were present in both resistant and susceptible isolates. Novel mutations emerged from the 11 targets, but distinctions between susceptible and resistant isolates were not evident, except for the prevalent kdr mutation in synthetic pyrethroid-resistant isolates. The quest for predictive molecular markers for monitoring acaricide resistance remains challenging. Nevertheless, by utilizing a representative group of isolates, we determined that several historical mutations were present in both resistant and susceptible isolates. Additionally, the study provides valuable genetic data on acaricide-resistant and susceptible isolates from different geographical regions, focusing on genomic regions implicated in resistance. This baseline data offers a critical foundation for further research and the identification of more reliable molecular markers. [ABSTRACT FROM AUTHOR]

The Rhipicephalus microplus tick is widely recognized as the most economically significant ectoparasite affecting cattle globally, particularly in the Neotropical region. In Mexico, at least 65% of the cattle are infested with R. microplus and are susceptible to tick-borne diseases. Integrated tick management strategies are required to maintain compatible levels of animal production and reduce the reliance on chemical acaricides for tick control. Therefore, this paper aims to analyze current methods for controlling tick infestation in extensively raised cattle using Integrated Tick Management (ITM) and to propose an ITM program suitable for implementation in the humid tropical region of Veracruz, Mexico. [ABSTRACT FROM AUTHOR]

Aims: Coxiella burnetii is a highly infectious organism that is easily spread through aerosols causing Q fever in humans. Ticks can harbour and transmit C. burnetii to animals, contributing to disease maintenance. Our aim was to examine the presence of C. burnetii in ticks in Uganda. Methods and Results: In this study, ticks were collected from five Ugandan districts and tested by real‐time PCR for C. burnetii (Coxiella outer membrane protein 1 gene). A total of 859 tick pools (9602 individual ticks) were tested, and pool positivity for C. burnetii was 5.5% (n = 47). Pooled prevalence differed by district; the highest was Luwero (7.3%), then Gulu (6.6%), and Kasese had the lowest (1.3%). However, district variation was not statistically significant (Fisher's exact = 0.07). Ticks collected from dogs and cats had the highest positivity rates [23/47, (48.9%)] followed by livestock (cattle, goats, sheep, and pigs) [18/47, (38.3%)] and vegetation [6/47, (12.8%)]. Haemaphysalis elliptica had the highest infection rates, followed by Rhipicephalus appendiculatus, Amblyomma variegatum and Rhipicephalus decoloratus had similar prevalence. Conclusions: Although ticks are not the primary transmitters of C. burnetii to humans, pathogen detection in ticks can be an indirect indicator of risk among animal hosts. Vulnerable populations, including occupations with close animal contact such as farming, butchery, and veterinary practice, have an increased risk of C. burnetii exposure. Veterinarians and clinicians should be aware that C. burnetii may cause human and animal illness in these regions. [ABSTRACT FROM AUTHOR]

Hard ticks are ectoparasites and vectors of many pathogens. Studies on hard ticks in cattle have rarely been conducted in northeastern Algeria. This study aimed to estimate the infestation rate, distribution, and biological diversity of hard tick species infesting 122 cattle in Mila, Jijel, and Guelma (northeastern Algeria) provinces during the summer of 2019. A total of 1,927 ticks belonging to two hard tick genera (Rhipicephalus; 85.83%, Hyalomma; 14.17%) and nine species were collected. Rhipicephalus (Boophilus) annulatus (54.5%) and Rhipicephalus bursa (28.18%) were widespread in northeastern Algeria. Several species were reported for the first time in the regions studied. In addition, the intensity of tick infestation did not vary according to breed, sex and age of cattle. The information gathered could help develop more effective tick control programmes in these regions. Further studies are needed in other regions of Algeria to generate a comprehensive national tick database. [ABSTRACT FROM AUTHOR]

Arthropods serve as efficient carriers for various life-threatening infections parasites, viruses and other harmful organisms throughout the world. In this study, Al-Aqiq Governorate of Al-Baha city served as the site where tick burden on camels (Camelus dromedarius) was assessed. The aim of the present investigation was to determine the diversity and prevalence of ticks. A total of 800 ticks, 756 adults and 44 nymphs were gathered and identified. Tick DNA was obtained from camels by utilizing commercially available kits. Polymerase chain reaction (PCR) was done on recovered DNA utilizing 12S rDNA and 16S ribosomal DNA fragments to analyze and identify the ticks. Three species of hard ticks were found in the two genera Hyalomma and Rhipicephalus. Hyalomma dromedarii (81.81%) and H. rufipes (17.35%) were the two species with the highest prevalence found on the domestic animal hosts, whereas R. sanguineus (had the lowest prevalence of 0.82%). This is a preliminary report of DNA barcode of tick species of camels (Camelus dormedarius) from Al-Baha in KSA and the Arabian Peninsula, which is a significant step towards broader phylogenetic studies on tick samples from this region. The results of our study provide valuable insights for healthcare administrators and government authorities regarding the frequency of hard ticks on mammalian hosts in Al-Aqiq Governorate of Al-Baha City, Saudi Arabia. This can also assist in regulating tick diseases, in particular during the epidemic time. [ABSTRACT FROM AUTHOR]

Respiration in ticks is highly efficient and exceptionally low. Ticks can survive years between bloodmeals by having low activity and respiration to conserve energetic resources. Our objective was to compare metabolic (VCO2) and activity rates across 6 tick species. We predicted that VCO2 would be different among species and scale linearly with activity and body mass. Activity and CO2 production were measured for 32 h in 6 tick species: Dermacentor andersoni, D. variabilis, Haemaphysalis longicornis, Rhipicephalus appendiculatus, R. microplus, and R. sanguineus. Individual ticks were measured for 30 min three times to ensure breathing occurred. Absolute and mass-specific VCO2, total activity, body mass, and ventilation patterns were compared among species. As expected, ticks did not always breathe during the 30-minute measurements, especially R. sanguineus. Ventilation patterns differed among species with R. microplus having primarily cyclic patterns and R. appendiculatus having discontinuous gas exchange. VCO2 did not scale with body mass in most species. Haemaphysalis longicornis and R. sanguineus had the lowest VCO2; however, H. longicornis was the second most active species. Life history, including questing behavior and range expansion, could be contributing to differences between species. For instance, H. longicornis had exceptionally low metabolic rates despite above average activity levels, suggesting an energetic advantage which may underlie recently documented range expansions in North America. Our results demonstrate how ticks utilize energetic resources to maximize longevity. Future research describing questing behavior and distribution modeling may help explain differences in metabolic rates and activity and impacts on life history traits. [ABSTRACT FROM AUTHOR]

Babesia ovis , commonly associated with ovine babesiosis, poses a significant threat to sheep health, often resulting in severe clinical manifestations and high mortality rates. However, the impact of B. ovis on goats has remained uncertain, prompting us to investigate its pathogenicity in caprine hosts. Experimental infections using B. ovis -infected blood inoculation and infected tick infestation, were conducted on spleen-intact (n=5) and splenectomized (n=5) goats. The experimental infection was performed using fresh blood obtained from a B. ovis -infected splenectomized sheep. One spleen-intact sheep served as a control for the experimental infection with B. ovis -infected Rhipicephalus bursa ticks. While all experimentally infected sheep (#501, #575) displayed severe clinical symptoms and high parasitemia, goats exhibited resistance, showing no significant clinical manifestations or sustained parasitemia. Notably, B. ovis was detected in two spleen-intact goats via nested PCR, prompting further investigation into their role as reservoirs for tick-borne transmission. These goats were then infested with Babesia spp.-free R. bursa larvae (0.1 gr) and adults (50 females and 50 males) for transstadial and transovarial transmission experiments respectively. Results indicated that chronically B. ovis -infected spleen-intact goats are not significant sources for maintaining the tick-borne transmission cycle of the parasite. These findings highlight the differential susceptibility of goats to B. ovis infection compared to sheep and their limited role as reservoirs for parasite transmission. Understanding the role of goats in B. ovis transmission and their resistance mechanisms can inform effective control measures and reduce economic losses in affected regions. Further research into caprine babesiosis and host immunological responses is essential to fully elucidate their possible role as reservoirs of the parasite, and underlying mechanisms of host susceptibility and parasite pathogenesis. [ABSTRACT FROM AUTHOR]

Background: One bioassay for detecting acaricide resistance in livestock ticks is the adult immersion test (AIT), wherein engorged ticks are briefly immersed into a solution of a particular acaricidal compound and examined for mortality, their egg-laying capacity and offspring hatchability in vitro. Usually, the recommended label dose or an established discriminating dose of an acaricide is used to determine high mortality (≥ 95%) of susceptible tick strains. Such a test intends to detect the presence of resistance in a tick population. However, the adult immersion test does not directly translate the bioassay results to the predicted efficacy in the field. In this paper, we used the AIT as an initial screening bioassay supplemented with the resistance intensity test (RIT), a novel larval-based bioassay, wherein the resistance level can be determined and translated to the expected field efficacy. This was done by adopting World Health Organisation (WHO) guidelines for resistance detection in mosquitoes, which combines a 1 × recommended dose with 5 × and 10 × concentrated doses to reveal low, moderate and high resistance intensity, respectively. Methods: Engorged Rhipicephalus microplus ticks were collected from cattle at six different ranches across Rio Grande do Sul, Brazil, as part of the state's acaricide resistance surveillance program. Groups of adult ticks from each field collection were subjected to the AIT from each field sample. Additionally, engorged female ticks from each ranch were allowed to lay eggs, and their larval progeny aged 14 to 28 days were then used in the RIT. Deltamethrin and a combination of cypermethrin, chlorpyrifos and piperonyl butoxide were used in both tests, and the results were statistically analysed. Results: The in vitro efficacy of deltamethrin against adult ticks in the AIT ranged between 8.74% and 25.38%. The corresponding RIT results on their larval progeny indicated a high resistance level. In the immersion test, the in vitro efficacy of the combination of cypermethrin, chlorpyrifos, and piperonyl butoxide against adult ticks ranged between 49.31% and 100%. The corresponding RIT results on their larval progeny indicated a similar response ranging from fully susceptible to low or moderate resistance. The Pearson correlation coefficient (r = 0.883) showed a high correlation between tick mortality at the 1 × recommended concentrations of acaricides in both tests. Conclusions: The resistance intensity test is a valuable addition to the range of bioassays currently available for detecting acaricide resistance by determining the level of acaricide resistance. This is relevant to whether or not to continue using a particular acaricidal class for controlling cattle ticks. [ABSTRACT FROM AUTHOR]

well known for its insecticidal, anti-inflammatory, antioxidant, anticancer, anti-rheumatic and antibiotic properties, Turmeric (Curcuma longa L.) Essential oil (EO), is effective in repelling and controlling many different pest species. The present study evaluates in vitro efficacy of turmeric EO against ectoparasitic tick, Rhipicephalus (Boophilus)annulatus collected from their natural host, domesticated cows. Repellency and toxicity of the EO on ectoparasitic ticks was analyzed with petri dish choice bioassay and AIT (Adult immersion test) against adult engorged females and nymphal stages of ticks. The Repellency Concentration (RC50) and Lethal Concentration (LC50) reproductive index, inhibition of oviposition and egg hatchability of treated ticks were estimated. GC-MS analysis identified Ar-turmerone as the major phytochemical, which induces adulticidal and repellant properties of EO. The nymphal stages of the ticks exhibited greater repellency on application of EO than the adult stage. Also, EO induced effective mortality in adult ticks. Further, this lethal concentration is capable of producing a decreased output in reproductive parameters namely, fecundity, % of oviposition and egg hatchability in surviving ticks thereby considerably reducing Rhipicephalus (Boophilus) R(B). annulatus population on its host. This study reveals the potency C. longa EO to be used as an effective pest control agent against R (B). annulatus infestation that can serve as an alternative to synthetic pesticides. [ABSTRACT FROM AUTHOR]

Background and Aim: Tick-borne pathogens pose a significant problem in canines, other animals, and humans worldwide. This study aimed to estimate the prevalence of Borrelia burgdorferi, Ehrlichia canis, and Coxiella burnetii in dogs and associated ticks in Egypt. Materials and Methods: Blood samples from 110 tick-infested dogs and 550 whole ticks (divided into 110 pools) were collected and tested for the targeted pathogens using polymerase chain reaction (PCR). Results: Of the 110 dog blood samples, B. burgdorferi DNA was detected in three samples, E. canis in six samples, and C. burnetii in one kenneled dog. Among the 110 tick pools, B. burgdorferi was detected in four pools, E. canis in 12 pools, and C. burnetii in three pools from kenneled dogs. The overall prevalence of the three agents in dog and tick samples were 3.18%, 8.18%, and 1.81%, respectively. Simultaneous positive PCR reactions in both dogs and their associated tick pools were observed in four cases. B. burgdorferi and E. canis were simultaneously detected in two dogs and two tick pools, whereas C. burnetii was detected in one dog but not in any tick pools. The three agents were simultaneously detected in one dog, but none were found in the corresponding tick pools. A mixed infection of C. burnetii and B. burgdorferi was observed in one dog and one tick pool. Conclusion: Molecular diagnosis is the most reliable method for detecting B. burgdorferi, E. canis, and C. burnetii in dogs and associated ticks. E. canis showed the highest prevalence in both dog and tick samples followed by B. burgdorferi while C. burnetti showed the lowest prevalence. The potential transmission of these diseases from companion dogs to humans through ticks presents a significant challenge for the One Health concept. [ABSTRACT FROM AUTHOR]

Background and Aim: Tick-borne pathogens pose a significant problem in canines, other animals, and humans worldwide. This study aimed to estimate the prevalence of Borrelia burgdorferi, Ehrlichia canis, and Coxiella burnetii in dogs and associated ticks in Egypt. Materials and Methods: Blood samples from 110 tick-infested dogs and 550 whole ticks (divided into 110 pools) were collected and tested for the targeted pathogens using polymerase chain reaction (PCR). Results: Of the 110 dog blood samples, B. burgdorferi DNA was detected in three samples, E. canis in six samples, and C. burnetii in one kenneled dog. Among the 110 tick pools, B. burgdorferi was detected in four pools, E. canis in 12 pools, and C. burnetii in three pools from kenneled dogs. The overall prevalence of the three agents in dog and tick samples were 3.18%, 8.18%, and 1.81%, respectively. Simultaneous positive PCR reactions in both dogs and their associated tick pools were observed in four cases. B. burgdorferi and E. canis were simultaneously detected in two dogs and two tick pools, whereas C. burnetii was detected in one dog but not in any tick pools. The three agents were simultaneously detected in one dog, but none were found in the corresponding tick pools. A mixed infection of C. burnetii and B. burgdorferi was observed in one dog and one tick pool. Conclusion: Molecular diagnosis is the most reliable method for detecting B. burgdorferi, E. canis, and C. burnetii in dogs and associated ticks. E. canis showed the highest prevalence in both dog and tick samples followed by B. burgdorferi while C. burnetti showed the lowest prevalence. The potential transmission of these diseases from companion dogs to humans through ticks presents a significant challenge for the One Health concept.

Canine vector-borne infections (CVBIs) are a global health problem. The military working dogs of Sri Lanka die at an early age, and CVBIs have been a leading speculated cause. We examined CVBIs in the working dogs of the Sri Lanka air force (SLAF) and free-roaming dogs (FRDs) and privately owned dogs (PODs) country-wide. Giemsa-stained smears were prepared and conventional PCR-positive DNA was subjected to sequencing and phylogeny. Of the 668 dogs sampled, 212 (31.7%) had one or more CVBIs. The prevalence of infections among the FRDs (40.0%) was significantly higher than SLAF working dogs (30.0%; χ2 = 10.5216; p = 0.0012) and PODs (26.2%; χ2 = 5.3414, p = 0.0208) but not between SLAF dogs and PODs (χ2 = 1.7655, p = 0.1838). Many infected dogs were asymptomatic (57.4%), which was higher among the FRDs. Seven infectious agents were identified: Babesia gibsoni, B. canis, Ehrlichia canis, Anaplasma platys, Leishmania sp., Hepatozoon canis, and filaria worms. The most common infection was B. gibsoni (13.8%), followed by E. canis (9.9%). Three tick species: Rhipicephalus linneai, Rhipicephalus haemaphysaloides and Haemophysalis bispinosa were found infesting the dogs. The SLAF dogs were thoroughly quarantined upon arrival, but the infection prevalence was similar to PODs. [ABSTRACT FROM AUTHOR]

The Rhipicephalus microplus tick causes enormous economic losses in livestock farming around the world. Despite several promising studies carried out with plant extracts such as Achyrocline satureioides against this ectoparasite, a major obstacle is related to pharmaceutical presentation forms. There is no study showing xantan gum-based hydrogel and polycaprolactone nanoparticles containing A. satureioides extract against R. microplus larvae. The objective of this study was to incorporate A. satureioides extract to develop a nanoformulation (AScn) and a hydrogel (ASlh) and evaluate them against R. microplus larvae with the purpose of increasing the contact time of the extract with the larvae and improve the effectiveness. The ethanolic extracts were incorporated in polycaprolactone nanoparticles and characterized via analysis of the mean hydrodinamic diameter and polidispersity index. The xanthan gum-based hydrogel formulation was prepared with crude extract of A. satureioides 40 mg/mL, 0.25% xanthan gum, and 8% poloxamer, to determine the bioadhesiveness of the formulation in bovine leather and the flow rate of the formulation in the animal. The results in larvae demonstrated that when evaluated in the form of a hydrogel (ASlh), mortality was higher, with 91.48% mortality at a concentration of 20 mg/mL presenting itself as an interesting alternative for controlling this ectoparasite. [ABSTRACT FROM AUTHOR]

The present study aimed to analyze the cladistics and population structure analysis of Rhipicephalus microplus ticks infesting buffaloes in Haryana, India, as well as the assessment of the anti-tick efficacy of the ethanolic extracts of Cassia fistula (bark, pod pulp, and flowers) against R. microplus larvae. The molecular characterization and population structure analysis were performed by targeting the amplification of the partial mitochondrial cytochrome C oxidase subunit 1 (cox1) gene, whereas anti-tick efficacy was evaluated using a larval packet test. The sequences generated herein revealed a homology of 98.26–100% to the GenBank-archived R. microplus sequences. In population structure analysis, high haplotype (0.500 ± 0.265) and low nucleotide (0.002 ± 0.001) diversities were recorded for the sequences generated in this study. Significantly negative neutrality indices were recorded for the overall dataset. The extracts were found to significantly affect mortality rates in a dose-dependent manner, and the ethanolic extracts of the bark, pod pulp, and flowers of C. fistula exhibited median lethal concentration (LC50) values of 27.989, 40.457, and 49.43 mg/mL, respectively. The LC50 value recorded for the combination of the ethanolic extracts of the bark, flower, and pod pulp of C. fistula was 19.724 mg/mL, whereas the synthetic acaricide ivermectin had an LC50 value of 351.56 mg/mL. In conclusion, R. microplus populations infesting cattle and buffalo hosts in India exhibited negligible genetic differentiation and high gene flow between them. Additionally, the combination of all C. fistula extracts could serve as a potential substitute for the synthetic acaricide. [ABSTRACT FROM AUTHOR]

The emergence of tick resistance against synthetic and eco-toxic chemical acaricides has stressed the need to find target-specific, non-toxic, and more potent alternatives such as botanicals. The current study was designed to investigate the acaricidal and repellent potential of ethyl acetate extract of Moringa oleifera seeds against Rhipicephalus microplus cattle ticks. Adult immersion test, larval immersion test, and tick climbing repellent assay were carried out to evaluate the acaricidal and repellent potential of M. oleifera extract. Five different concentrations (20, 10, 5, 2.5, and 1.25 %) of the ethyl acetate extract of M. oleifera were prepared to evaluate the acaricidal and repellent potential. Different parameters like adult tick mortality, larval mortality, egg hatchability, inhibition of egg hatchability, oviposition reduction, reproductive index, reproductive efficiency index, tick repellency, and product effectiveness were determined. Ethyl acetate extract of M. oleifera showed 70% adult mortality after 24 h treatment when 20% concentration was used. Similarly, 73% larval tick mortality was observed at 20% concentration. The results also showed the dose-dependent response of ethyl acetate extract of M. oleifera seeds against egg hatchability, inhibition of egg hatchability, oviposition reduction, reproductive index, reproductive efficiency index, and tick repellency, confirming that 20% concentration is effective as an acaricide and repellent against R. microplus. Therefore, the tested extract can be considered a possible candidate for controlling R. microplus in cattle. [ABSTRACT FROM AUTHOR]

Background: In Ethiopia, ticks are the major threat to cattle productivity and production, leading to considerable economic losses. The current study was designed to estimate the prevalence of ixodid tick infestation, identify species, assess major risk factors associated with tick infestation and assess public awareness. Methods: A cross‐sectional and questionnaire‐based study was conducted from January 2022 to June 2022 in the Aleltu district. The study animals were selected using a simple random sampling method. Results: Of the 400 cattle examined, 303 (75.8%) were found to be infested by one or more tick species. Six species of ticks were identified that belonged to three genera: Amblyomma, Hyalomma and Rhipicephalus, and the subgenus Rhipicephalus (Boophilus). The most common tick species identified in terms of their prevalence and dominance were Rh. (Bo) decoloratus, Rh. evertsi, Am. variegatum, Hy. rufipes, Rh. bergeoni and Rh. praetextatus. In the present study, Rh. (Bo) decoloratus was the most prevalent (56.8%) in the study area. Among the risk factors considered, the prevalence of tick species had a statistically significant (p < 0.05) association with the age, production systems and body condition of animals. Out of 110 people interviewed, 107 (97.3%) believed there was a tick infestation in their village, and almost all farmers 103(93.6%) in the study area were unaware that ticks serve as vectors. Conclusions: The present study provides preliminary information on the prevalence of tick infestation and the composition of ticks in the Aleltu district. Ticks are a major problem for the cattle in the study area. Therefore, the problem observed in the study area alarms the district and calls for a comprehensive control strategy. [ABSTRACT FROM AUTHOR]

Background: Acaricide resistance in cattle ticks is a significant concern in (sub)tropical regions, particularly Brazil. The Larval Packet Test (LPT) is the standard laboratory bioassay for resistance diagnosis, which requires triplicates of seven acaricidal dilutions plus controls to cover larval mortalities ranging between 0 and 100%. The value of the LPT lies in providing resistance ratios based on the ratio between the LC50 calculated with potentially resistant and susceptible ticks. However, LC50 ratios are difficult to translate into practical advice for farmers. Moreover, LPT requires laboratory facilities to maintain susceptible tick colonies, and it takes 6 weeks to obtain the larvae to be tested by LPT derived from engorged female ticks collected from cattle in the field. Our novel approach was twofold: first, we upgraded the LPT to the Resistance Intensity Test (RIT) by adopting the latest WHO guidelines for resistance detection in mosquitoes, which combines a 1 × recommended dose with 5 × and 10 × concentrated doses to reveal low, moderate and high resistance intensity, respectively. This reduced the number of test papers and tick larvae and, more importantly, provided relevant information on the resistance level. Our second innovative step was to abolish testing larvae entirely and expose partly engorged adult ticks to the same acaricidal doses immediately after removing them from cattle in the field. This resulted in the Rapid Tick exposure Test (RaTexT®), wherein partly engorged adult ticks were exposed to an acaricide-impregnated, specially designed matrix providing test results within 24 h. This approach directly compared resistance detection in tick larvae in the RIT with resistance in adult ticks in RaTexT®. Methods: Laboratory validation was conducted in Brazil with resistant and susceptible colonies of Rhipicephalus microplus ticks. For field validation, adult R. microplus ticks collected from different cattle farms in Brazil were evaluated for resistance to RaTexT®, and the results regarding their larval progenies were compared with those for the RIT. Partly engorged adult ticks derived from cattle infested with laboratory and field strains of R. microplus were exposed to deltamethrin in RaTexT® containers, which contained six rows of four interconnected compartments, accommodating five to eight semi-engorged female ticks with a preferred size ranging between 5 and 8 mm. The corresponding larvae of each strain were exposed in the RIT to the same deltamethrin concentrations in filter papers. Results: In RaTexT®, mortality in adult ticks from a resistant strain of R. microplus from Seropédica in Brazil was 38.4%, 54.2% and 75.0% at the 1 ×, 5 × and 10 × doses of deltamethrin, respectively. In RIT, mortality of larvae from the same resistant strain was 2.0%, 4.9% and 19.5% at 1 ×, 5 × and 10 × doses, respectively. The results of RaTexT® and RIT agreed since both tests identified a high level of resistance based on a cut-off of 90% mortality. In RaTexT®, mortality of adult ticks from a susceptible strain originating from Porto Alegre was 73.8%, 92.9% and 97.6% at the 1 ×, 5 × and 10 × doses, respectively. In RIT, mortality of larvae from the susceptible strain was 95.2%, 95.2% and 96.8% at the 1 ×, 5 × and 10 × doses, respectively. Interestingly, both tests identified a low number of unexpected resistant individuals in the susceptible strain since the mortality of neither larvae nor adults reached 100%. This effect remained unnoticed in the LPT, wherein a resistance ratio of 159.5 was found based on the LC50 of the resistant strain divided by the LC50 of the susceptible strain. Next, RaTexT® was compared with RIT using adult and larval ticks derived from three field strains of R. microplus in Brazil. RaTexT® detected high levels of resistance to deltamethrin in adult ticks in all strains, which was confirmed in larvae tested by the RIT. Both tests agreed on the same resistance level with significantly lower mortality rates in larvae than in adult ticks. Conclusions: RaTexT® is a novel rapid pen-site test for detecting acaricide resistance in adult livestock ticks. It potentially replaces laborious tests using larval ticks and provides results within 24 h relevant to acaricide resistance management of livestock ticks. [ABSTRACT FROM AUTHOR]

Babesia ovis, transmitted by Rhipicephalus bursa ticks, is the causative agent of ovine babesiosis, a disease characterized by fever, anemia, hemoglobinuria, and high mortality in sheep. This study investigates whether sheep that survived babesiosis without treatment can serve as a source of infection for B. ovis-free host-seeking R. bursa larvae in a later season. Three donor sheep were experimentally infected with B. ovis, and after six months, persistence of B. ovis was assessed through blood and tick transmission experiments. Blood from donor sheep was intravenously injected into three recipient sheep, while donor sheep were also infested with B. ovis-free R. bursa larvae. Engorged nymphs molted to adults, and new recipient sheep were infested with these ticks. All recipient sheep were monitored for B. ovis for 100 days using microscopic, serological, and molecular approaches. The presence of B. ovis was confirmed in the recipient sheep that received blood, leading to clinical infection in two. However, no B. ovis was detected in recipient sheep infested with ticks. These results suggest that sheep recovering from B. ovis infection do not serve as a source of infection for R. bursa larvae in subsequent seasons. [ABSTRACT FROM AUTHOR]

Background and Aim: Climatic conditions significantly impact the life stages and distribution patterns of ticks and tickborne diseases. South Africa's central plateau and various biomes offer a distinct landscape for studying the geography's effects. The study estimated tick species prevalence and the influential factors on their survival. Materials and Methods: Ticks were gathered from communal cattle in South African provinces including Limpopo (LP), Gauteng (GP), Mpumalanga (MP), KwaZulu-Natal (KZN), the Eastern Cape (EC), and the Free State (FS), from September 2020 to November 2022. Using data from South African weathercasts, the annual climate was assessed. Results: A total of 3,409 ticks were collected, with the highest infestation observed in KZN (45%), followed by LP (26%), EC (19%), GP (5%), MP (2%), and the FS (2%). The most prevalent tick species were Amblyomma hebraeum (55.1%), Rhipicephalus evertsi evertsi (13.9%) and Rhipicephalus (Boophilus), and decoloratus (11.9%). Other species included R. (Boophilus) microplus (10.85%), Hyalomma marginatum (4.8%), Rhipicephalus appendiculatus (1.4%), Harpalus rufipes (0.8%), Rhipicephalus exophthalmos (0.2%), Rhipicephalus glabroscutatus (0.2%), Rhipicephalus sanguineus (0.2%), Haemaphysalis silacea (0.5%), Ixodes pilosus (0.1%), and Rhipicephalus simus (0.1%). The infestations were most prevalent on farms in Pongola and KZN. The temperature fluctuated between 12°C and 35°C during data gathering, while humidity varied between 40% and 65%. Conclusion: This study showed that ticks survive optimally in warm temperatures and high humidity conditions. Livestock farms with high tick infestations may be associated with several risk factors. These practices could involve suboptimal grazing, insufficient acaricidal treatment, and detrimental effects resulting from traditional animal husbandry. Future research is needed to longitudinally evaluate the effects of climate change on tick populations, pathogen transmission, hosts, habitats, and human behavior, influencing potential exposure risks. [ABSTRACT FROM AUTHOR]

Rhipicephalus microplus poses a significant economic threat due to its role in transmitting Babesia bigemina, B. bovis and Anaplasma marginale. Chemical control methods, commonly employed, encounter challenges like resistance, high costs, and environmental concerns. Emerging as an alternative, entomopathogenic fungi, particularly Beauveria bassiana, present a promising avenue for biological control. Molecular identification using the internal transcribed spacer (ITS1-5.8-ITS4) region ensures accurate species identification. This study investigated two B. bassiana strains, assessing their molecular characterization, impact on R. microplus mortality, and reproductive effects on adult females. The Reproductive Aptitude Index (RAI) is employed to evaluate tick egg viability post-treatment, providing insights into the potential of these fungi for tick control. Results indicate the BbLn2021-1 strain causes 96% mortality, and BbSf2021-1 induces 100% mortality. The commercial strain exhibited 28% mortality, while the control treatment showed 12%. Statistical analysis reveals a significant difference between treatments (p < 0.01). The Reproductive Efficiency Index (REI) underscores BbSf2021-1is superiority, yielding lower egg weights than other treatments. Regarding the RAI, BbLn2021-1 and BbSf2021-1 show no significant differences but differ significantly from the commercial and control (p < 0.01). These findings suggest that strains isolated and characterized from the natural environment could have potential applications in field trials, serving as a biocontrol alternative for R. microplus ticks. [ABSTRACT FROM AUTHOR]

Rhipicephalus microplus (Acari: Ixodidae) is a highly invasive tick responsible for significant economic losses to cattle industry worldwide. The increasing global reports on acaricide resistant tick populations warrant development of alternate eco-friendly approaches for suppressing the tick populations and vectored pathogens. The present study aimed to evaluate the acaricidal activity of essential oils (EOs): Cedar oil (CO), Garlic oil (GO), Peppermint oil (PO) and their combinations against R. microplus by larval packet test. Six concentrations each of individual EOs and their combinations (10, 5, 2.5, 1.25, 0.625 and 0.31%) were evaluated. The lethal concentrations (LC) of individual EOs and their combinations along with values of Combination Index (CI) and Dose Reduction Index (DRI) were estimated to assess the effects of interactions (synergistic, additive or antagonistic) of EO mixtures. Among the individual oils, GO showed the highest efficacy with lowest LC50, LC90 and LC95 (95% CL) values at 2.19% (1.96–2.43%), 4.00% (3.48–4.98%) and 4.74% (4.01–6.23%), respectively. Among combinations, highest acaricidal property was exhibited by GO + PO (LC50, LC90 and LC95 values of 2.63, 4.87 and 5.81%) with CI value of 0.598 indicating moderate synergism, while the CO + GO + PO combination (LC50, LC90 and LC95 values of 1.67, 9.97 and 16.54%) exhibited slight synergism with CI value at 0.872 and favourable DRI of 8.24, 1.85 and 4.76 for PO, GO and CO, respectively. The present study seems to be pioneer to assess the combination effect of these EOs against R. microplus and could help in development of an effective and eco-friendly product for tick control. [ABSTRACT FROM AUTHOR]

Equine piroplasmosis is not fully understood regarding pathogenicity, prophylaxis, host immune response expression, and specific vectors. Accurately identifying the parasite vector is crucial for developing an effective control plan for a particular infection. This study focused on morphologically identifying two Hyalomma species (H. anatolicum and H. marginatum) and one Rhipicephalus annulatus (R. annulatus) at the species level. The identification process was followed by phylogenetic analysis using the neighbor-joining method based on the cytochrome oxidase subunit 1 (COXI) gene as a specific vector for Theileria equi (T. equi) in horses. T. equi was diagnosed morphologically and molecularly from infected blood samples and crushed tick species using conventional PCR. Subsequently, phylogenetic analysis based on the amplification of the 18 S rRNA gene was conducted. The obtained sequence data were evaluated and registered in GenBank under accession numbers OR064161, OR067911, OR187727, and OR068139, representing the three tick species and the isolated T. equi, respectively. The study demonstrated that T. equi infection leads to immune system suppression by significantly increasing the levels of oxidative stress markers (CAT, GPx, MDA, and SOD) (P ≤ 0.0001), with this elevation being directly proportional to parasitemia levels in infected blood cells. Furthermore, a correlation was observed between parasitemia levels and the expression of immune response infection genes (IFN-gamma, TGF-β1, and IL-1β cytokines) in infected horses compared to non-infected equine. Common macroscopic symptoms indicating T. equi infection in horses include intermittent fever, enlarged lymph nodes (LN), and tick infestation. [ABSTRACT FROM AUTHOR]

The Xinjiang Uygur Autonomous Region (Xinjiang) borders eight countries and has a complex geographic environment. There are almost 45.696 million herded sheep in Xinjiang, which occupies 13.80% of China's sheep farming industry. However, there is a scarcity of reports investigating the role of sheep or ticks in Xinjiang in transmitting tick-borne diseases (TBDs). A total of 894 ticks (298 tick pools) were collected from sheep in southern Xinjiang. Out of the 298 tick pools investigated in this study, Rhipicephalus turanicus (Rh. turanicus) and Hyalomma anatolicum (H. anatolicum) were identified through morphological and molecular sequencing. In the southern part of Xinjiang, 142 (47.65%), 86 (28.86%), and 60 (20.13%) tick pools were positive for Rickettsia spp., Theileria spp., and Anaplasma spp., respectively. Interestingly, the infection rate of Rickettsia spp. (73%, 35.10%, and 28.56–41.64%) was higher in Rh. turanicus pools than in H. anatolicum pools (4%, 4.44%, and 0.10–8.79%) in this study. Fifty-one tick pools were found to harbor two pathogens, while nineteen tick pools were detected to have the three pathogens. Our findings indicate the presence of Rickettsia spp., Theileria spp., and Anaplasma spp. potentially transmitted by H. anatolicum and Rh. turanicus in sheep in southern Xinjiang, China. [ABSTRACT FROM AUTHOR]

Abstract Background Southeast Asia is regarded as a hotspot for the diversity of ixodid ticks. In this geographical region, Vietnam extends through both temperate and tropical climate zones and therefore has a broad range of tick habitats. However, molecular-phylogenetic studies on ixodid tick species have not been reported from this country. Methods In this study, 1788 ixodid ticks were collected from cattle, buffalos and a dog at 10 locations in three provinces of northern Vietnam. Tick species were identified morphologically, and representative specimens were molecularly analyzed based on the cytochrome c oxidase subunit I (cox1) and 16S rRNA genes. Fifty-nine tick species that are indigenous in Vietnam were also reviewed in the context of their typical hosts in the region. Results Most ticks removed from cattle and buffalos were identified as Rhipicephalus microplus, including all developmental stages. Larvae and nymphs were found between January and July but adults until December. Further species identified from cattle were Rhipicephalus linnaei, Rhipicephalus haemaphysaloides, Amblyomma integrum and Haemaphysalis cornigera. Interestingly, the latter three species were represented only by adults, collected in one province: Son La. The dog was infested with nymphs and adults of R. linnaei in July. Phylogenetically, R. microplus from Vietnam belonged to clade A of this species, and R. haemaphysaloides clustered separately from ticks identified under this name in China, Taiwan and Pakistan. Amblyomma integrum from Vietnam belonged to the phylogenetic group of haplotypes of an Amblyomma sp. reported from Myanmar. The separate clustering of H. cornigera from Haemaphysalis shimoga received moderate support. Conclusions Three tick species (R. linnaei, A. integrum and H. cornigera) are reported here for the first time in Vietnam, thus increasing the number of indigenous tick species to 62. Clade A of R. microplus and at least R. linnaei from the group of Rhipicephalus sanguineus sensu lato occur in the country. There is multiple phylogenetic evidence that different species might exist among the ticks that are reported under the name R. haemaphysaloides in South and East Asia. This is the first report of A. integrum in Southeastern Asia. Graphical Abstract

Background: Southeast Asia is regarded as a hotspot for the diversity of ixodid ticks. In this geographical region, Vietnam extends through both temperate and tropical climate zones and therefore has a broad range of tick habitats. However, molecular-phylogenetic studies on ixodid tick species have not been reported from this country. Methods: In this study, 1788 ixodid ticks were collected from cattle, buffalos and a dog at 10 locations in three provinces of northern Vietnam. Tick species were identified morphologically, and representative specimens were molecularly analyzed based on the cytochrome c oxidase subunit I (cox1) and 16S rRNA genes. Fifty-nine tick species that are indigenous in Vietnam were also reviewed in the context of their typical hosts in the region. Results: Most ticks removed from cattle and buffalos were identified as Rhipicephalus microplus, including all developmental stages. Larvae and nymphs were found between January and July but adults until December. Further species identified from cattle were Rhipicephalus linnaei, Rhipicephalus haemaphysaloides, Amblyomma integrum and Haemaphysalis cornigera. Interestingly, the latter three species were represented only by adults, collected in one province: Son La. The dog was infested with nymphs and adults of R. linnaei in July. Phylogenetically, R. microplus from Vietnam belonged to clade A of this species, and R. haemaphysaloides clustered separately from ticks identified under this name in China, Taiwan and Pakistan. Amblyomma integrum from Vietnam belonged to the phylogenetic group of haplotypes of an Amblyomma sp. reported from Myanmar. The separate clustering of H. cornigera from Haemaphysalis shimoga received moderate support. Conclusions: Three tick species (R. linnaei, A. integrum and H. cornigera) are reported here for the first time in Vietnam, thus increasing the number of indigenous tick species to 62. Clade A of R. microplus and at least R. linnaei from the group of Rhipicephalus sanguineus sensu lato occur in the country. There is multiple phylogenetic evidence that different species might exist among the ticks that are reported under the name R. haemaphysaloides in South and East Asia. This is the first report of A. integrum in Southeastern Asia. [ABSTRACT FROM AUTHOR]

[Display omitted] • The geographic distribution of Rhipicephalus linnaei is much wider than previously known. • Rhipicephalus linnaei was recorded on a dingo. • The record of R. linnaei on a dingo suggest that dingoes might aid the spread of Ehrlichia canis in Australia. • We discuss possible incursion routes and how E. canis has apparently spread rapidly in Australia. The tropical brown dog tick, Rhipicephalus linnaei , is a tick of much medical, veterinary, and zoonotic importance. This tick has a nearly world-wide distribution due to its ability to survive and propagate in kennels and houses. Rhipicephalus linnaei is the vector of Ehrlichia canis , the causative agent of canine monocytic ehrlichiosis, an often debilitating disease of canids and, occasionally, humans. To prevent incursion of E. canis into Australia, dogs entering Australia have been required to have a negative immunofluorescence antibody test for E. canis. In May 2020 however, E. canis was detected in Western Australia. The detection of E. canis in Australia prompted disease investigation and concerted surveillance for R. linnaei and E. canis in regions across Australia. These investigations revealed that R. linnaei was established far beyond the previously recognised geographic range limits of this tick. In the present paper, using records from various collections, published data, and data from our network of veterinarian collaborators and colleagues, we update the current geographic range of R. linnaei in Australia. Our analyses revealed that the geographic range of R. linnaei in Australia is much wider than was previously supposed, particularly in Western Australia, and in South Australia. We also map, for the first time, where E. canis has been detected in Australia. Last, we discuss the possible routes of incursion and subsequently the factors which may have aided the spread of E. canis in Australia which led to the establishment of this pathogen in Australia. [ABSTRACT FROM AUTHOR]

Rhipicephalus microplus is the parasitic species that causes the most damage to Mexican and global livestock due to direct and indirect losses, such as the increase in multidrug resistance and cross-resistance. Currently, there are few studies on resistance to macrocyclic lactones in Mexico, most of them in the south. This study aimed to evaluate the status of ivermectin resistance in R. microplus in northeastern Mexico and its associated risk factors. A total of 20 populations of Rhipicephalus microplus were collected in the states of Veracruz, Nuevo León, Tamaulipas, and San Luis Potosí, and they were analyzed with the larval immersion test. Mortality data were subjected to a Probit analysis, estimating lethal concentrations (LC) of 50 % and 99 % and their respective 95 % confidence intervals (95 % CI), and to determine possible risk factors, a multivariate analysis and 2 x 2 contingency tables were performed for the exposure variables, with a 95 % confidence interval, and a binomial logistic regression model for those variables with a P=0.05. Eighty (80) percent of the analyzed populations showed resistance with ranges of RR50= 2.07-11.14 and RR99= 3.03-47.93 (P=0.05), and through the binomial logistic regression, it was observed that the variable of frequency of treatments obtained a P=0.0134, a result that proved to be significant. [ABSTRACT FROM AUTHOR]

Mycoplasma agalactiae (Ma) is considered the primary causative agent of contagious agalactia (CA) in sheep and goats, which causes severe losses to the small ruminant dairy industry. As early as 1816, it was thought that environmental factors played a role in pathogen maintenance in endemic areas. Specifically, recent studies hypothesized a vector role for arthropods in the epidemiology of disease. The aim of this study was to investigate the presence and anatomical localization of Ma in naturally infected Riphicephalus bursa ticks to better evaluate tick–pathogen interactions. Salivary glands and ovaries of confirmed Ma-positive R. bursa were analyzed to look for the Ma antigen using immunohistochemistry (IHC). IHC showed strong positivity to Ma in the cytoplasm of salivary cells as well as in cells from the ovary. Our work demonstrated for the first time the crossing of the tick midgut barrier by Ma and the subsequent infection of organs capable of spreading the infection, and this result represents an absolute novelty in disease-related knowledge. Our preliminary results provide conclusive evidence of the potential vector role represented by hard ticks in the epidemiology of CA. Further field and laboratory investigations are necessary to confirm the tick role in the transmission of clinical CA. [ABSTRACT FROM AUTHOR]

Simple Summary: The tick species involved in the transmission of Babesia aktasi, which is widespread in the Mediterranean region, is unknown. However, studies have shown that Rhipicephalus bursa is the most common tick species in the regions where the prevalence of B. aktasi is widespread. This finding increases the possibility that R. bursa may serve as a vector for the transmission of B. aktasi and encourages the evaluation of the vector competence of R. bursa. For this purpose, clinical babesiosis was induced in an immune-suppressed indigenous donor goat. Babesia spp.-free R. bursa larvae (n = 2000) and adults (n = 25) obtained from laboratory colonies fed on the donor goat. Following oviposition, PCR analysis of engorged female carcasses and engorged nymphs revealed the presence of B. aktasi, whereas no positivity was found in unfed larvae and adult ticks. The subsequent developmental stages of these ticks were used to infest three additional immune-suppressed goats. No clinical signs of babesiosis were observed in the infested goats. Moreover, molecular analysis did not detect DNA in the goats. These results demonstrated that R. bursa does not transmit B. aktasi, neither transovarially nor transstadially. A recent molecular survey revealed a high prevalence of Babesia aktasi in indigenous goats from the Mediterranean region of Türkiye, coinciding with heavy Rhipicephalus bursa infestations. This geographical overlap has raised the possibility that R. bursa may serve as a vector for the parasite. To evaluate the potential of R. bursa to serve as a vector for the parasite, an experimental study was conducted in indigenous goats. An immune-suppressed donor goat was intravenously injected with 15 mL of the cryopreserved B. aktasi stabilate, resulting in severe clinical babesiosis and parasitemia. Subsequently, R. bursa larvae and adults derived from Babesia-free laboratory colonies were allowed to feed on the infected donor goat. After oviposition, engorged female carcasses, representative engorged nymphs, unfed larvae, and adult pools were used for DNA extraction and PCR analysis. No PCR positivity was detected in any of the DNA samples, except for those with engorged female carcasses and nymphs. Three immune-suppressed recipient goats were infested with the unfed immature and mature ticks consuming the blood of a donor infected with B. aktasi. No clinical or parasitological findings were encountered in the recipient for 40 days post-infestation. These findings indicated that R. bursa was not a competent vector for B. aktasi. [ABSTRACT FROM AUTHOR]

Background: Ticks are obligate hematophagous ectoparasites involved in transmitting viruses of public health importance. The objective of this work was to identify the Jingmen tick virus in hard ticks from the Colombian Caribbean, an arbovirus of importance for public health. Methods: Ticks were collected in rural areas of Córdoba and Cesar, Colombia. Taxonomic identification of ticks was carried out, and pools of 13 individuals were formed. RNA extraction was performed. Library preparation was performed with the MGIEasy kit, and next-generation sequencing (NGS) with MGI equipment. Bioinformatic analyses and taxonomic assignments were performed using the Galaxy platform, and phylogenetic analyses were done using IQ-TREE2. Results: A total of 766 ticks were collected, of which 87.33% (669/766) were Rhipicephalus microplus, 5.4% (42/766) Dermacentor nitens, 4.2% (32/766) Rhipicephalus linnaei, and 3.0% (23/766) Amblyomma dissimile. Complete and partial segments 1, 2, 3, and 4 of Jingmen tick virus (JMTV) were detected in the metatranscriptome of the species R. microplus, D. nitens, and A. dissimile. The JMTVs detected are phylogenetically related to JMTVs detected in Aedes albopictus in France, JMTVs detected in R. microplus in Trinidad and Tobago, JMTVs in R. microplus and A. variegatum in the French Antilles, and JMTVs detected in R. microplus in Colombia. Interestingly, our sequences clustered closely with JMTV detected in humans from Kosovo. Conclusions: JMTV was detected in R. microplus, D. nitens, and A. dissimile. JMTV could pose a risk to humans. Therefore, it is vital to establish epidemiological surveillance measures to better understand the possible role of JMTV in tropical diseases. [ABSTRACT FROM AUTHOR]

Simple Summary: Arthropods are a large and diverse group of animals, some of which are pests, while others transmit human and livestock diseases as they bite them to feed on blood. Chemical-based vector and pest control for decades has made many arthropods resistant to the chemicals used. So, there is a need to investigate other control agents, such as the biological, arthropod-killing fungus Metarhizium anisopliae, for the ability to infect and kill human and livestock disease-transmitting arthropods. In this study, we tested if the fungus M. anisopliae infects and kills mosquitoes, tsetse flies, and ticks. This was performed by finding out how long mosquitoes lived after being infected with fungus spores, as well as the amount of fungus spores suitable to lead to their death. The same optimal concentration of fungus that killed mosquitoes also successfully killed tsetse flies and ticks. We recommend that the fungus be formulated in a suitable concentration of 109 spores/mL and its ability to kill mosquitoes, tsetse flies, and ticks be confirmed in the field. This would lead to the development of a fungal formulation that can be sprayed on livestock such as cattle, for the exposure of multiple blood-feeding and disease-transmitting arthropods at the same time, to impact their survival. Arthropod vectors are responsible for a multitude of human and animal diseases affecting poor communities in sub-Saharan Africa. Their control still relies on chemical agents, despite growing evidence of insecticide resistance and environmental health concerns. Biorational agents, such as the entomopathogenic fungus Metarhizium anisopliae, might be an alternative for vector control. Recently, the M. anisopliae isolate ICIPE 7 has been developed into a commercial product in Kenya for control of ticks on cattle. We were interested in assessing the potential of controlling not only ticks but also disease-transmitting mosquitoes and tsetse flies using cattle as blood hosts, with the aim of developing a product for integrated vector management. Laboratory bioassays were carried out with M. anisopliae, isolate ICIPE 7 and isolate ICIPE 30, to compare efficacy against laboratory-reared Anopheles arabiensis. ICIPE 7 was further tested against wild Glossina fuscipes and Rhipicephalus spp. Dose–response tests were implemented, period of mosquito exposure was evaluated for effects on time to death, and the number of spores attached to exposed vectors was assessed. Exposure to 109 spores/mL of ICIPE 7 for 10 min resulted in a similar mortality of An. arabiensis as exposure to ICIPE 30, albeit at a slower rate (12 vs. 8 days). The same ICIPE 7 concentration also resulted in mortalities of tsetse flies (LT50: 16 days), tick nymphs (LT50: 11 days), and adult ticks (LT50: 20 days). Mosquito mortality was dose-dependent, with decreasing LT50 of 8 days at a concentration of 106 spores/mL to 6 days at 1010 spores/mL. Exposure period did not modulate the outcome, 1 min of exposure still resulted in mortality, and spore attachment to vectors was dose-dependent. The laboratory bioassays confirmed that ICIPE 7 has the potential to infect and cause mortality to the three exposed arthropods, though at slower rate, thus requiring further validation under field conditions. [ABSTRACT FROM AUTHOR]

The study assessed the acaricidal properties of 20 compounds derived from essential oils against the Rhipicephalus microplus tick, a significant menace to tropical livestock with considerable economic losses. A novel methodology was devised, involving the determination of mortality times for R. microplus larvae upon direct contact with these compounds. Mortality times were compared against a negative control (soybean oil) and two positive controls (commercial pour-on products). Tests were conducted in 48-well polyethylene plates, with around 100 larvae immersed in 200 µl of oil (at a 100% dose). The 10 compounds exhibiting the shortest mortality times were subsequently diluted in soybean oil at varying concentrations. Notably, thymol exhibited potent acaricidal activity, with the lowest effective dose (1.56%) resulting in larval mortality within 15 minutes, whereas positive controls necessitated over 66 minutes. A correlation was established between the molecular structure of the compounds and their acaricidal efficacy, indicating that cyclic compounds containing 10 carbon atoms demonstrated heightened lethality compared to acyclic counterparts. This innovative methodology enables the rapid identification of substances with substantial acaricidal potential in vitro, yielding results within minutes, in stark contrast to the traditional larval immersion test, which demands a minimum of 24 hours for conclusive outcomes. [ABSTRACT FROM AUTHOR]

Ticks serve as vectors and reservoirs of various Borrelia species, potentially causing diseases in humans and animals. Mazandaran, a fertile green land in northern Iran, provides ample grazing grounds for livestock and harbors at least 26 hard tick species. This study investigated Borrelia infection in hard ticks from forest areas in this region and compared their genetic identity with the species data in the GenBank database. A total of 2,049 ticks were collected manually from mammalian hosts or using dragging and flagging methods. These ticks were then grouped into 190 pools and 41 individuals based on host, species, developmental stage, and gender. A real-time PCR (qPCR) detected Borrelia DNA in 26 pools from female, male, and nymph of Rhipicephalus annulatus (n = 17) and Ixodes ricinus (n = 9) ticks and one individual female Haemaphysalis punctata tick. The generated partial flaB and glpQ sequences from qPCR-positive Rh. annulatus ticks exhibited the highest identities of 98.1-100% and 98.2% with Borrelia theileri and closely related undefined isolates. Additionally, in phylogenetic analysis, these sequences clustered within well-supported clades with B. theileri and the closely related undefined isolates from various geographic regions, confirming the presence of B. theileri in the north of Iran. Divergence in B. theileri flaB and glpQ sequences across various geographical areas suggests potential subspeciation driven by adaptations to different tick species. This divergence in our flaB sequences implies the possible introduction of B. theileri-infected ticks from different geographical origins into Iran. [ABSTRACT FROM AUTHOR]

The aim of this work was to analyze the R. microplus (Canestrini, 1888) infestation in two bovine herds with different degrees of natural resistance (i.e., Hereford and Braford) to ticks subjected to an identical chemical treatment scheme to ticks at the same farm, to demonstrate the impact on tick control of the incorporation of a more resistant bovine breed. Two groups of ten Hereford and Braford cows each were subjected to eleven chemical treatments between August 2022 and October 2023 (four fluazuron, two fipronil 1%, one ivermectin 3.15% and four immersion in a dipping vat with a combination of cypermethrin 10% and ethion 40%). Tick population was shown to be susceptible to ivermectin, fluazuron and the mix cypermethrin 10%-ethion 40% and resistant to fipronil according to in vitro tests. Tick infestation was significantly greater in the Hereford cows than in the Braford cows. Tick infestation in both Hereford and Braford breeds was similar when treatment with functional drugs was applied, but when a block of the treatments was done with drugs with decreased functionality due to resistance (i.e. fipronil), treatment failure was manifested more strongly in the most susceptible breed. The incorporation of cattle breeds with moderate or high resistance to R. microplus is instrumental to optimize the efficacy and sustainability of chemical control of ticks in a scenario where resistance to one or more chemical groups is almost ubiquitous, because it favors the biological control of this parasite. [ABSTRACT FROM AUTHOR]

Rhipicephalus microplus poses a substantial threat to livestock health and agricultural economies worldwide. Its remarkable adaptability to diverse environments and hosts is a testament to its extensive genetic diversity. This review delves into the genetic diversity of R. microplus, employing three pivotal genetic markers: the cytochrome c oxidase I (COX1) gene, ribosomal genes, and microsatellites. The COX1 gene, a crucial tool for genetic characterization and phylogenetic clustering, provides insights into the adaptability of ticks. Ribosomal genes, such as internal transcribed spacer regions (ITS-1 and2) as well as 18S and 28S, are routinely utilized for species differentiation. However, their use is limited due to indels (insertions and deletions). Microsatellites and minisatellites, known for their high polymorphism, have been successfully employed to study populations and genetic diversity across various tick species. Despite their effectiveness, challenges such as null alleles and marker variations warrant careful consideration. Bm86, a well-studied vaccine candidate, exhibits substantial genetic diversity. This diversity directly influences vaccine efficacy, posing challenges for developing a universally effective Bm86-based vaccine. Moreover, the review emphasizes the prevalence of genes associated with synthetic pyrethroid resistance. Identifying single nucleotide polymorphisms in the acaricide-resistant genes of R. microplus has facilitated the development of molecular markers for detecting and monitoring resistance against synthetic pyrethroids. However, mutations in sodium channels, the target site for synthetic pyrethroid, correlate well with the resistance status of R. microplus, which is not the case with other acaricide target genes. This study underscores the importance of understanding genetic diversity in developing effective tick management strategies. The choice of genetic marker should be tailored based on the level of taxonomic resolution and the group of ticks under investigation. A holistic approach combining multiple markers and integrating additional molecular and morphological data may offer a more comprehensive understanding of tick diversity and relationships. This research has far-reaching implications in formulating breeding programs and the development of vaccine against ticks and tick-borne diseases (TTBDs) as well as strategies for the management of resistant ticks. [ABSTRACT FROM AUTHOR]

Purpose : Rhipicephalus (Boophilus) microplus is one the most significant ectoparasite in cattle farming in tropical and subtropical regions, causing problems to livestock health worldwide. The control of this ectoparasite primarily relies on the use of synthetic acaricides. However, the emergence of acaricide resistance has stimulated the search for new control alternatives, including phytocompounds with acaricidal and insecticidal potential. The aim of this study was to evaluate the acaricidal potential of Lavandula dentata essential oil against the engorged females of R. (B.) microplus. Methods: Engorged females were obtained from infested bovines in dairy farms in Pernambuco, Brazil. L. dentata essential oil was extracted, and adult immersion test assays were performed using the following oil concentrations: 0.2%, 0.4%, 0.6%, 0.8%, and 1%. Results : L. dentata essential oil at a concentration of 1% was lethal to all engorged females, and concentrations of 0.6% and 0.8% caused mortality of 98.6% and 99.1%, respectively. These concentrations disrupted the reproductive capacity of engorged females, reducing oviposition by more than 90% and preventing egg hatching by over 87%. Conclusion: The data revealed that L. dentata essential oil possesses effective pharmacological properties against R. (B.) microplus and could be used for tick control following in vivo evaluation, thus contributing to mitigating the negative impacts of synthetic acaricide use. [ABSTRACT FROM AUTHOR]

This study was carried out to determine the prevalence of ectoparasites in sheep and goats in the Konya province of Türkiye.A total of 818 sheep and 155 goats selected through covenient sampling method from 30 different ovine breeders of Konya were screened for the presence of ectoparasites (e.g., lice, fleas, ticks, and mites) as per the standard parasitological procedures. According to the results, 19% of the sheep and 64%of the goats harbouredectoparasites on their bodies. Irrespective of the species of animal, overall distribution of ectoparasites was 12%, 6%, 4%, and 26% for ticks, lice, fleas and mites, respectively. The magnitude of ticks, lice, fleas, and mites were 25%, 23%, 16%, and 0%, on goats and 10%, 3%, 2%, and 5%on sheep respectively. The identified species of ectoparasites were Rhipicephalus (R.) bursa (7%), R. Turanicus (2.1%), Babesia (B.) ovis (2.6%), R. sanguineus (0.6%), Ctenocephalides canis (1.5), Psoroptes ovis (2.9%), Sarcoptes scabiei ovis (2.1) and Pulex (P) irritans (0.3%) on sheep, and Rhipicephalus bursa (13%), R. sanguineus (3.9%), R. Turanicus (2.6%), Hyalomma (H.) detritum (4.5%), H. anatolicum excavatum (1.3%), Bovicola capri (14.2%), Linognathus africanus (8.4%), Ctenocephalides felis felis (12.3) and P. irritans (3.87%) on goats. As a result, due to the high prevalence of ectoparasites, combating ectoparasites is vital to prevent economic losses for breeders. [ABSTRACT FROM AUTHOR]

total of 140 fully engorged adult female ticks were included for the present study. Out of this, 20 ticks were used for performing larval packet test (LPT) and remaining 120 ticks were used in adult immersion test (AIT). Polyherbal aqueous formulation consisting of paste of 10 gm each of Garlic pearls (Allium sativum), Tobacco leaves (Nicotiana tabacum), Tulsi leaves (Ocimum tenuiflorum), Lantana camara leaves (Shrub verbena), Sweet flag rhizome (Acorus calamus), and 20 gm each of Neem leaves (Azadirachta indica) and Turmeric powder (Curcuma longa) was used as acaricidal agent in the present study. The paste was dissolved in one liter of water and strained. In AIT, polyherbal formulation exhibited notable inhibition of oviposition and adult tick mortality. Furthermore, In LPT, it demonstrated increased effectiveness on R. microplus larvae from the Mhow region, resulting in a higher mean percent mortality. These findings highlight the promising potential of the polyherbal formulation as a potent acaricidal agent in tick control strategies. [ABSTRACT FROM AUTHOR]

Blood feeding and digestion are vital physiological activities essential for the survival and reproduction of ticks. Chemical acaricides viz., ivermectin, amitraz and fipronil, are known to act on the central nervous system, resulting in the mortality of ticks. The present study is focused on the effect of these acaricides on the midgut and gut enzymes of Rhipicephalus microplus. The ultra-thin sections of midgut of ivermectin-treated ticks showed irregular basal membrane and ruptured digestive vesicles. Amitraz treatment resulted in a notable decrease in digestive cells with pleats in the basal membrane, while fipronil-exposed ticks exhibited reduced digestive cells, loss of cellular integrity, and disintegration of the basal membrane and muscle layer. The gut tissue homogenate of ivermectin and fipronil treated ticks showed a significant reduction of cathepsin D level, 76.54 ± 3.20 μg/mL and 92.67 ± 3.72 μg/mL, respectively, as compared to the control group (150.0 ± 3.80 μg/mL). The leucine aminopeptidase level (4.27 ± 0.08 units/mL) was significantly decreased in the ivermectin treated ticks compared to other treatment groups. The acid phosphatase activity (29.16 ± 0.67 μmole/min/L) was reduced in the ivermectin treated group whereas, increased activity was observed in the fipronil and amitraz treated groups. All the treatment groups revealed increased alkaline phosphatase levels (17.47–26.72 μmole/min/L). The present finding suggests that in addition to the established mechanism of action of the tested acaricides on the nervous system, the alterations in the cellular profile of digestive cells and enzymes possibly affect the blood digestion process and thus the synthesis of vital proteins which are essential for vitellogenesis, and egg production in ticks. [ABSTRACT FROM AUTHOR]

Interactions within the tick microbiome involving symbionts, commensals, and tick‐borne pathogens (TBPs) play a pivotal role in disease ecology. This study explored temporal changes in the microbiome of Rhipicephalus microplus, an important cattle tick vector, focusing on its interaction with Anaplasma marginale. To overcome limitations inherent in sampling methods relying on questing ticks, which may not consistently reflect pathogen presence due to variations in exposure to infected hosts in nature, our study focused on ticks fed on chronically infected cattle. This approach ensures continuous pathogen exposure, providing a more comprehensive understanding of the nesting patterns of A. marginale in the R. microplus microbiome. Using next‐generation sequencing, microbiome dynamics were characterized over 2 years, revealing significant shifts in diversity, composition, and abundance. Anaplasma marginale exhibited varying associations, with its increased abundance correlating with reduced microbial diversity. Co‐occurrence networks demonstrated Anaplasma's evolving role, transitioning from diverse connections to keystone taxa status. An integrative approach involving in silico node removal unveils the impact of Anaplasma on network stability, highlighting its role in conferring robustness to the microbial community. This study provides insights into the intricate interplay between the tick microbiome and A. marginale, shedding light on potential avenues for controlling bovine anaplasmosis through microbiome manipulation. [ABSTRACT FROM AUTHOR]

Despite is known to have widespread distribution and the most active species of the family Chlorocyphidae, the molecular data of Rhinocypha fenestrella (Rambur, 1842) are relatively scarce. The present study is the first that examined the genetic diversity and phylogeographic pattern of the peacock jewel-damselfly R. fenestrella by sequencing the cytochrome C oxidase I (cox1) and 16S rRNA gene regions from 147 individuals representing eight populations in Malaysia. A total of 26 and 10 unique haplotypes were revealed by the cox1 and 16S rRNA genes, respectively, and 32 haplotypes were recovered by the concatenated sequences of cox1+16S. Analyses indicated that haplotype AB2 was the most frequent and the most widespread haplotype in Malaysia while haplotype AB1 was suggested as the common ancestor haplotype of the R. fenestrella that may arose from the Negeri Sembilan as discovered from cox1+16S haplotype network analysis. Overall haplotype and nucleotide diversities of the concatenated sequences were Hd = 0.8937 and Pi = 0.0028, respectively, with great genetic differentiation (FST = 0.6387) and low gene flow (Nm = 0.14). Population from Pahang presented the highest genetic diversity (Hd = 0.8889, Pi = 0.0022, Nh = 9), whereas Kedah population demonstrated the lowest diversity (Hd = 0.2842, Pi = 0.0003, Nh = 4). The concatenated sequences of cox1+16S showed genetic divergence ranging from 0.09% to 0.97%, whereas the genetic divergence for cox1 and 16S rRNA genes were 0.16% to 1.63% and 0.01% to 0.75% respectively. This study provides for the first-time insights on the intraspecific genetic diversity, phylogeographic pattern and ancestral haplotype of Rhinocypha fenestrella. The understanding of molecular data especially phylogeographic pattern can enhance the knowledge about insect origin, their diversity, and capability to disperse in particular environments. [ABSTRACT FROM AUTHOR]

Background and Aim: Anaplasma marginale is an obligate intraerythrocytic rickettsial parasite that infects cattle in tropical and subtropical regions. There is no evidence that A. marginale inoculation can be used to culture Rhipicephalus annulatus in rabbits. This study aimed to determine the molting of R. annulatus larvae, nymphs, and adults on rabbits as well as nymphs and adults of R. annulatus on calves with or without A. marginale. Transstadial, horizontal, and transovarial transmissions of A. marginale in R. annulatus reared on rabbits and calves were evaluated. Materials and Methods: Engorged female ticks were collected from field samples of A. marginale-infected and noninfected cattle. We divided the eight rabbits into two groups: A and B. Group A rabbits were infected with A. marginale through parenteral inoculation, whereas Group B rabbits were kept as a control. The "clean rabbits" in Group B were observed for tick rearing without A. marginale. Polymerase chain reaction was used to screen A. marginale in rabbits and stages of tick. The complete life cycle of R. annulatus with or without A. marginale was observed on rabbits. Results: A 6.5-day longer life cycle was observed in ticks harboring A. marginale than in ticks without A. marginale. To observe transstadial transmission, transstadial, horizontal, and transovarial transmissions of A. marginale in R. annulatus ticks were experimentally observed in one clean calf fed separately with infected nymphs and female adult ticks. Conclusion: We experimentally observed transovarian, transstadial, and transovarial transmission of A. marginale in R. annulatus ticks as a biological vector reared on calves and rabbits. We used rabbits as a model animal for rearing R. annulatus ticks and culture of A. marginale. [ABSTRACT FROM AUTHOR]

Synthetic pesticides used to combat ticks lose their effectiveness against certain species and can affect human health. The present study evaluated in vitro and in vivo the effect of the aqueous extract of Pimpinella anisum (P. anisum) seeds against Rhipicephalus sanguineus and Ixodes affinis, domestic dog ticks. In the in vitro evaluations, concentrations of 1.25, 2.5, 5, 10, 25, 50, 75 and 100 % of the aqueous extract of P. anisum were applied directly to ticks. The concentrations that had the highest effectiveness in immobilization were 50 %, 75 % and 100 %, but the latter caused immobilization for a longer time (55.89 ± 0.16 min). In the in vivo evaluation, the concentrated aqueous extract was applied to ticks attached to the skin of domestic dogs. Amitraz, a commercial tickicide, was used as a positive control. Both the concentrated aqueous extract and Amitraz caused 100 % of tick detaching. Nonetheless, concentrated aqueous extract of P. anisum seeds was more effective in reducing the average time of tick detaching (60.81 ± 3.17 min) compared to the commercial tickicide Amitraz (145.12 ± 15.97 min). This research suggests that the p-anisaldehyde identified in the aqueous extract could be linked to the immobilization and detaching of R. sanguineus and I. affinis from domestic dogs, suggesting that this extract could be used as a biopesticide to control ticks in domestic dogs. [ABSTRACT FROM AUTHOR]

In Ecuador, the main tick species affecting cattle are Rhipicephalus microplus and Amblyomma cajennense sensu lato. Understanding their spatial distribution is crucial. To assess their distribution, data from 2895 farms visited between 2012 and 2017 were utilized. Ticks were collected during animal inspections, with each farm's location georeferenced. Bioclimatic variables and vapor pressure deficit data were obtained from Climatologies at High resolution for the Earth´s Land Surface Areas (CHELSA) dataset. They were overlaid to develop predictive maps for each species using Random Forest (RF) models. The cross-validation results for RF prediction models showed high accuracy for both R. microplus and A. cajennense s.l. presence with values of accuracy = 0.97 and 0.98, sensitivity = 0.96 and 0.99, and specificity = 0.96 and 0.93, respectively. A carefully selected subset of bioclimatic variables was used to describe the presence of each tick species. Higher levels of precipitation had positive effect on the presence of R. microplus but a negative effect on A. cajennense s.l. In contrast, isothermality (BIO3) was more important for the presence of A. cajennense s.l. compared to R. microplus. As a result, R. microplus had a broader distribution across the country, while A. cajennense s.l. was mainly found in coastal areas with evident seasonality. The coexistence of both species in some regions could be attributed to transitional zones, whereas high altitudes limited tick presence. This information can aid in developing appropriate tick management plans, particularly considering A. cajennense s.l.'s broad host range species and R. microplus's specificity for cattle. Moreover, the predictive models can identify areas at risk of associated challenging hemoparasite, requiring special attention and mitigation measures. [ABSTRACT FROM AUTHOR]

We conducted an analysis of the complete mitochondrial genome of Rhipicephalus haemaphysaloides, a tick species known for transmitting various bacteria and viruses. The mitochondrial genome of R. haemaphysaloides has a length of 14,739 bp and consists of 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), 2 ribosomal RNA genes (rRNAs), and 2 control regions. By utilizing the maximum likelihood method, we established the phylogenetic relationship among R. haemaphysaloides and other species within the Rhipicephalus genus of the Ixodidae family. This analysis revealed that R. haemaphysaloides and other Rhipicephalus species belong to the same clade, further affirming the taxonomic placement of R. haemaphysaloides within the Rhipicephalus genus. Furthermore, we compared the mitochondrial genomes of R. haemaphysaloides isolates from Changning, Yunnan Province, China, with isolates from Yangxin, Ganzhou, and Yingtan, Hubei Province, China. In summary, our investigation offers genetic proof endorsing the taxonomic categorization and phylogenetic placement of Ixodidae by assessing the entire mitochondrial genome of R. haemaphysaloides. [ABSTRACT FROM AUTHOR]