Detection of tick-borne pathogens in Rhipicephalus bursa ticks collected from the autochthonous Garrano breed of horses in Portugal.

The Garrano is a semi-feral horse breed native to several mountains in the northern Iberian Peninsula. Despite being endangered, this unique breed of pony has managed to survive in the wild and continues to be selectively bred, highlighting their remarkable resilience and adaptability to harsh environments. Wildlife plays a critical role in the survival of tick vectors in their natural habitats and the transfer of tick-borne pathogens, as they can serve as reservoir hosts for many agents and amplifiers for these vectors. The semi-feral lifestyle of the Garrano horses makes them particularly vulnerable to exposure to numerous tick species throughout the year. Therefore, the aim of this study was to investigate the occurrence of Anaplasma, Ehrlichia, Babesia, Theileria, and spotted fever rickettsiae in the Garrano horse ticks to obtain a knowledge of circulating agents in this host population. The collected ticks (n = 455) were identified as Rhipicephalus bursa. DNA specimens were organized in pools of 5 ticks, for molecular screening. Pools PCR results confirmed the presence of Candidatus Rickettsia barbariae (n = 12 for the ompB gene, n = 11 for the ompA gene and n = 6 for the gltA gene), Babesia bigemina (n = 1), Babesia caballi (n = 3), Theileria equi (n = 15) and Theileria haneyi (n = 1).These results confirm the circulation of an emerging rickettsial spotted fever group member, Candidatus R. barbariae, in R. bursa ticks. Our findings demonstrated that Candidatus R. barbariae co-circulates with B. bigemina and T. equi, which are vectored by R. bursa. We are reporting for the first time, the detection of T. haneyi among R. bursa ticks feeding in the Garrano horses in Portugal. Surveillance studies for tick-borne infections are essential to provide information that can facilitate the implementation of preventive and control strategies.

Heartworm-, Flea-, and Tick-associated Diseases in Dogs: A Review of Common Parasites and Drug Classes Prophylactic Against Them.

Throughout recorded history, the canine-human connection has varied by custom, purpose, and intensity. In many cultures worldwide, dogs have long been considered essential workers, protectors and guardians, and, often, an integral part of the family unit. Ensuring the health and quality of life of those companion animals is essential to preserving the bond between dogs and their owners. Fortunately, advances in veterinary science continue to improve treatments and cures for and prophylaxis against a variety of deadly canine diseases, several of which can be sourced to ectoparasites or endoparasites. For many veterinary patients, a customized preparation often proves to be the best therapeutic option, but many compounding-pharmacy stores also include a retail component that offers ready access to manufactured prescription medications, including those prophylactic against canine flea, tick, or heartworm infestation. Because dog owners often need guidance in selecting such products and assistance with obtaining them, this article will be of special interest to ompounders in those pharmacies. To that end, the following content addresses common canine parasites and classes of drugs that prevent the illnesses they cause, with emphasis on heartworm disease.

Prophylaxis Against Heartworm Infection and Flea or Tick Infestation in Dogs: Single Agents and Combination-Drug Products.

From ancient times to the present, parasites and the diseases they transmit have jeopardized the health and wellbeing of working and companion canines worldwide. Many common pests that afflict dogs can be classified as ectoparasites (e.g., fleas, ticks, lice), which serve as vectors of pathogens transmitted as the organism feeds or defecates; or endoparasites (e. g, helminths, protozoa), which can cause slowly progressive subclinical canine diseases as well as acute illnesses associated with high morbidity and mortality rates. Safe, effective antiparasitic prophylaxis in dogs remains a topic of major interest to both veterinarians and their clients, especially with respect to the prevention of canine heartworm infection and flea or tick infestation. Many compounders, especially those whose pharmacy includes a retail component, counsel veterinarians and pet owners about preparations and commercially available medications that prevent or treat parasitic infestations and provide assistance in obtaining those therapies. To support such efforts, this article provides information about single agents and combination-drug products prophylactic against common canine parasites, emerging resistance to those medications, and the toxic effects that such treatments can engender in some canine breeds.

MORPHOLOGICAL AND MOLECULAR CHARACTERIZATION OF AMBLYOMMA SCUTATUM (ACARI: IXODIDAE) ACCIDENTALLY INTRODUCED IN ITALY.

Eight ticks were found in Comacchio (FE), Italy parasitizing a young black iguana (Ctenosaura similis) that had been accidentally transported in a commercial plant container from Costa Rica. Specimens were identified morphologically as Amblyomma scutatum and then confirmed by the barcoding of the mitochondrial cytochrome c oxidase subunit 1 gene. Amblyomma scutatum is a common tick known to infest reptiles in Central America, Mexico, and Venezuela, but not in Europe. In Italy, the possibility for this tick to become endemic is unlikely because of the absence of its principal hosts. Nevertheless, this finding confirms the high risk of introducing exotic species that is linked with global commerce and therefore the need for veterinary control of shipments.

The effect of feeding on different hosts on the egg proteins in Haemaphysalis qinghaiensis tick.

The majority of ixodid ticks display host-specificity to varying extents. Feeding on different hosts affects their development and reproduction. Consequences can be analyzed at the level of the egg, as it is the initial stage of tick development. Tick egg proteins are abundant and diverse, providing nutrients for embryonic development. However, studies on tick egg profiles are scarce. In this study, we aimed to analyze whether feeding Haemaphysalis qinghaiensis ticks on the yaks (Bos grunniens) and domestic sheep (Ovis aries) has an impact on the variety and variability of the egg proteome. Detached engorged females were used to lay eggs, which were then collected, dewaxed, and subjected to protein extraction. The extracted egg proteins were enzymatically digested using Filter-Aided Sample Preparation (FASP), and the unique peptides were separated and detected by Liquid Chromatography-tandem Mass Spectrometry (LC-MS/MS). The MS data were searched against the previously constructed whole tick transcriptome library of H. qinghaiensis, and the UniProt database for the identification of tick-derived egg proteins. The analysis revealed 49 and 53 high-confidence proteins identified in eggs collected from B. grunniens (EggBg) and O. aries (EggOa), respectively. Of these, 46 high-confidence proteins were common to both egg types, while three were unique to EggBg and seven to EggOa. All the identified proteins mainly belonged to enzymes, enzyme inhibitors, transporters, and proteins with unknown functions. The differential abundance analysis showed that nine proteins were significantly more present in EggBg, while six were significantly more present in EggOa. Overall, enzymes were the most diverse group, while vitellogenin (Vg) was the most abundant. Blood meal uptake on different hosts has a certain effect on the egg proteome composition and the abundance of some proteins, but it may also lead to compensation of protein roles.

Ticks (Acari: Ixodidae) on resident and migratory wild birds in Orinoquia region, Colombia.

Several species of hard ticks, including those of the genera Ixodes, Haemaphysalis, Amblyomma, and Rhipicephalus, are of medical and veterinary importance and have been reported in association with Neotropical wild birds. Colombia, known for its great bird diversity, has 57 confirmed tick species. However, there are few studies on the association between wild birds and ticks in Colombia. The Orinoquia region, a migratory center in Colombia, provides a unique opportunity to study wild bird-tick associations and their implications for tick-borne disease dynamics. Our study, conducted between October and December 2021, aimed to identify hard ticks infesting resident and migratory wild birds in the department of Arauca and to assess the presence of bacteria from the genera Anaplasma, Borrelia, Ehrlichia, Rickettsia, and piroplasms. A total of 383 birds were examined, of which 21 were infested. We collected 147 ticks, including Amblyomma dissimile (larvae), Amblyomma longirostre (nymphs), Amblyomma mixtum (adults), and Amblyomma nodosum (larvae and nymphs). We did not detect bacterial DNA in the tested ticks; however, piroplasm DNA was detected in ticks from three of the infested birds. Of the 21 bird-tick associations, six are new to the Americas, and interesting documentation of piroplasm DNA in A. longirostre, A. nodosum, and A. dissimile ticks from wild birds in the region. This study provides valuable insights into the ticks associated with wild birds and their role in the dispersal of ticks and pathogens in Colombia, enhancing our understanding of tick life cycles and tick-borne disease dynamics.

Range of Ixodes laguri, a nidicolous tick that parasitizes critically endangered rodents, with details on its western distribution limit in Austria.

The nidicolous tick Ixodes laguri is a nest-dwelling parasite of small mammals that mainly infest rodents of the families Cricetidae, Gliridae, Muridae and Sciuridae. There is no proven vectorial role for I. laguri, although it is suggested that it is a vector of Francisella tularensis. In this study, a first map depicting the entire geographical distribution of I. laguri based on georeferenced locations is presented. For this purpose, a digital data set of 142 georeferenced locations from 16 countries was compiled. Particular attention is paid to the description of the westernmost record of I. laguri in the city of Vienna, Austria. There, I. laguri is specifically associated with its main hosts, the critically endangered European hamster (Cricetus cricetus) and the European ground squirrel (Spermophilus citellus). These two host species have also been mapped in the present paper to estimate the potential distribution of I. laguri in the Vienna metropolitan region. The range of I. laguri extends between 16-108∘ E and 38-54∘ N, i.e. from Vienna in the east of Austria to Ulaanbaatar, the capital of Mongolia. In contrast to tick species that are expanding their range and are also becoming more abundant as a result of global warming, I. laguri has become increasingly rare throughout its range. However, I. laguri is not threatened by climate change, but by anthropogenic influences on its hosts and their habitats, which are typically open grasslands and steppes. Rural habitats are threatened by the intensification of agriculture and semi-urban habitats are increasingly being destroyed by urban development.

Risk factors affecting the feeding site predilection of ticks on cattle in Ghana.

Ticks are important disease vectors affecting animal health and causing substantial economic loss, especially in the tropics and subtropics. To examine the tick burden of cattle and associated risk factors for tick infestation, ticks were collected from 388 cattle within five regions in Ghana. Most of the cattle were males (50.3%) and generally older than 3 years (65%). Of the animals sampled, 2187 ticks were collected with a mean tick burden of 5.6 ticks per cattle, and the average tick burden on the udder/scrotum being significantly higher than in the anal region (Generalized Linear Mix Model [GLMM], p = 0.01197). The tick species identified were predominantly Amblyomma variegatum (42.6%) and Hyalomma rufipes (26.2%). High proportions of cattle examined were found to have A. variegatum infesting the udder/scrotum. Furthermore, H. rufipes infested mostly the anal region compared to other examined body parts (OR 14.8, 95% CI 8.6-25.4, p < 0.001). Using the GLMM, tick abundance was found to be significantly higher in cattle older than 3 years. The tick burden in the udder/scrotum was higher than that from the chest and leg/thigh of the cattle (GLMM, p < 0.05). The tick burden at the anal region was also significantly higher than the leg/thigh and chest. This study indicates that the preferred attachment sites of ticks on cattle are species-dependent and effective treatment with acaricides should take into consideration the udder/scrotum and anal regions as well as prioritizing older cattle.

Rhipicephalus sanguineus from Hungarian dogs: Tick identification and detection of tick-borne pathogens.

The brown dog tick, Rhipicephalus sanguineus is a complex of tick species with an unsettled species concept. In Europe, R. sanguineus is considered mainly a Mediterranean tick with sporadic findings in central and northern Europe. R. sanguineus is known as a vector of a range of pathogens of medical and veterinary importance, most of which not yet reported as autochthonous in Hungary. A total of 1839 ticks collected by veterinarians from dogs and cats were obtained in Hungary. The study aims at precise determination of ticks identified as R. sanguineus and detection of pathogens in collected ticks. All ticks were morphologically determined and 169 individuals were identified as R. sanguineus. A subset of 15 ticks was selected for molecular analysis (16S rDNA, 12S rDNA, COI). Phylogenetic analyses invariably placed sequences of all three markers into a single haplotype identified as R. sanguineus sensu stricto. All 169 brown dog ticks were tested for the presence of A. platys, E. canis, R. conorii, B. vogeli and H. canis. None of the investigated ticks was positive for the screened pathogens, though A. phagocytophilum sequence was detected in a single tick.

Resistance to natural tick infestation varies with age and coat and hair traits in a tropically adapted beef cattle breed.

Rhipicephalus (Boophilus) microplus causes considerable livestock production losses. Knowledge of the traits that influence tick resistance contributes to the development of breeding strategies designed to improve herd productivity. Within this context, this study evaluated the resistance of Caracu, a tropically adapted cattle breed, to R. microplus. Tick count, hair length, coat thickness, and coat color were evaluated in 202 naturally tick-infested females (cows and heifers) over a period of 18 months. Blood samples were collected from all animals during the winter season for hematological analysis. Data were analyzed using Pearson correlations, generalized linear models, and principal component analysis. Correlation coefficients of tick count with coat color, coat thickness, and hair length were estimated within each season. Hematological parameters were only included in the winter season analysis and were analyzed by the restricted maximum likelihood method using log-transformed data. No differences in blood parameters were observed between animals with and without ticks. However, tick count was negatively correlated with erythrocytes (-0.29) and hematocrit (-0.24) and positively correlated with mean corpuscular hemoglobin (0.21) and mean corpuscular hemoglobin concentration (0.25). These findings suggest that higher tick counts lead to a decrease in erythrocytes but also to an increase in the amount of hemoglobin per erythrocyte, which could reduce the damage caused by low erythrocyte levels due to tick hematophagy, delaying or preventing anemia. Although tick infestation on pasture was demonstrated by the infestation of all staff members during herd management, none of the animals exhibited high tick counts, providing evidence of resistance of Caracu animals to R. microplus. Tick infestation was influenced by age class (cows > heifers), season (spring and summer > fall and winter), coat thickness (>1.5 mm > <1.5 mm), and hair length (>6 mm > <6 mm). Three components were extracted by principal component analysis, which accounted for 69.46% of data variance. The findings of this study will contribute to the development of efficient strategies aimed at reducing economic losses due to tick infestation and could be applied in animal breeding to select for tick resistance traits, reducing chemical control strategies and consequently improving sustainable livestock production.

Ticks (Acari: Ixodidae) and rickettsiae associated with wild boars in a rural area of Minas Gerais, Brazil.

Wild boars or feral pigs are classified by the Brazilian Institute for the Environment and Renewable Resources (IBAMA) in "Category I of invasive exotic species". They cause economic losses, harm the environment, serve as hosts and reservoirs for several zoonotic disease agents, and provide a blood meal for tick species that act as vectors for zoonotic diseases. The objective of this study was to identify tick species on wild boars, assess host-seeking ticks in the related environment, and identify other potential tick hosts coexisting with wild boars on a farm located in the state of Minas Gerais, southeastern Brazil. Additionally, the study aimed to determine the presence of rickettsiae in these arthropods and assess the exposure of wild boars to rickettsiae species from the Spotted Fever Group and Rickettsia bellii through serology. A total of 3585 host-seeking ticks from three species (Amblyomma sculptum - 41.58%; Amblyomma dubitatum - 0.39% and Rhipicephalus microplus - 0.05%) were collected in the environment and A. sculptum was the most abundant species. Thirty-one wild boars were evaluated, resulting in the collection of 415 ticks, all of which were A. sculptum. Rickettsia DNA was not detected in samples of A. sculptum and R. microplus from the environment or in A. sculptum ticks from wild boars. However, all A. dubitatum ticks (n = 14) had Rickettsia bellii DNA confirmed by the species-specific PCR protocol. Out of the 31 serum samples from wild boars, 24 reacted with at least one Rickettsia antigen. Among these, seven individuals exhibited a reaction to a probable homologous antigen (PHA) of three rickettsiae species: R. rickettsii (n = 3), R. amblyommatis (n = 3) and R. rhipicephali (n = 1). Despite the high prevalence of seroreactivity, titers were low, indicating limited exposure to Rickettsia spp. Camera traps generated 874 animal records, capturing a total of 1688 individuals. At least 11 species of birds and 14 species of mammals (12 wild and two domestic) shared the environment with wild boars and potentially shared ticks with them. These findings provide baseline information for understanding the sharing of ticks and tick-borne pathogens between wild boars and other animals within the Cerrado biome. Further studies are necessary to monitor the potential and actual risk of wild boars to harbor infected ticks and their role in the transmission and maintenance cycle of Rickettsia spp.

Molecular identification, risk factor assessment, and phylogenetic analysis of tick-borne pathogens in symptomatic and asymptomatic cattle from South-Eastern Iran.

Tick-borne pathogens (TBPs) represent a substantial threat to cattle globally, exerting adverse impacts on production, health, and economic viability. This study delves into the prevalence and implications of TTBPs in cattle sourced from resource-limited smallholder livestock farms situated in southeastern Iran, proximate to Afghanistan and Pakistan. Blood and tick specimens were systematically collected from a cohort of 230 cattle, comprising 150 asymptomatic and 80 symptomatic individuals. Genomic DNA isolated from blood samples underwent rigorous examination for the presence of key TBPs, including Anaplasma marginale, A. phagocytophilum, A. bovis, A. centrale, Babesia bigemina, and Theileria annulata, utilizing multiple genetic markers. Nucleotide sequence analysis facilitated the reconstruction of phylogenetic relationships. The study also evaluated various potential risk factors, such as clinical status, gender, age, breed, tick infestation, and management practices, to elucidate their associations with TTBPs. Among the cattle cohort, a staggering 87.8% (202/230) tested positive for at least one pathogen. Prevalence statistics encompassed A. marginale (72.2%), T. annulata (68.3%), A. phagocytophilum/A. platys-like complex (66.1%), A. centrale (16.7%), B. bigemina (10.0%), and A. bovis (6.1%). Remarkably, mixed infections involving two, three, and four pathogens were detected in 23%, 52.1%, and 2.2% of animals, respectively. Notably, all asymptomatic cattle were positive for at least one TBP. Tick infestation was observed in 62.2% (143/230) of cattle, predominantly caused by Hyalomma anatolicum (82.5%), Rhipicephalus (Boophilus) annulatus (13.1%), and R. sanguineus sensu lato (4.4%). Risk factors linked to TBPs encompassed tick infestation, older age, and crossbred animals. Clinical presentations among symptomatic cattle encompassed fever, anemia, weight loss, anorexia, jaundice, and enlarged superficial lymph nodes. This study underscores the pivotal role of asymptomatic carriers in the propagation of TTBPs within endemic regions. Furthermore, it emphasizes the potential for the implementation of molecular diagnostics to unmask subclinical infections, thereby affording the opportunity for targeted interventions aimed at ameliorating the burden of TTBPs in resource-constrained smallholder dairy farms.

Self-emulsifying drug delivery systems (SEDDS) containing Cymbopogon citratus essential oil: Enhancing the stability and acaricide efficacy against Rhipicephalus (Boophilus) microplus.

The objectives of this study were to develop a self-emulsifying drug delivery system (SEDDS) to enhance the stability and efficacy of Cymbopogon citratus essential oil or lemongrass oil (LEO) against cattle tick larvae and engorged females. The system with the highest oil loading in SEDDS was composed of LEO (23.33%w/w), Tween 80: SGKH 4000 in a 2:1 ratio as surfactant (66.67%w/w), and propylene glycol as co-surfactant (10%w/w). The selected SEDDS-LEO has a particle size of 18.78 nm with a narrow size distribution (polydispersity index of 0.27). Notably, the stability of SEDDS was superior to that of the original oil, both during long-term storage and under accelerated conditions. SEDDS-LEO at oil concentrations ranging from 1.458% to 5.833% w/v showed a significantly higher percentage of egg-laying reduction against adult ticks compared with the original oil at the same concentrations (p < 0.05). Furthermore, SEDDS-LEO demonstrated greater larvicidal efficacy than the original oil, with lower LC50 and LC90 values of 0.91 mg/mL and 1.20 mg/mL, respectively, whereas the original oil's LC50 and LC90 values were 1.17 mg/mL and 1.74 mg/mL, respectively. Our findings indicate that SEDDS-LEO is a promising candidate for use as an acaricide in the control of tick populations in dairy cattle.

Dermacentor (Indocentor) auratus Supino 1897: Potential geographic range, and medical and veterinary significance.

Dermacentor (Indocentor) auratus Supino, 1897 occurs in many regions of Southeast Asia and South Asia. In many regions of Southeast Asia and South Asia, targeted tick sampling and subsequent screening of collected D. auratus ticks have detected pathogenic bacteria and viruses in D. auratus. These disease-causing pathogens that have been detected in D. auratus include Anaplasma, Bartonella, Borrelia, Rickettsia (including spotted fever group rickettsiae), African swine fever virus, Lanjan virus, and Kyasanur forest disease virus. Although D. auratus predominantly infests wild pigs, this tick is also an occasional parasite of humans and other animals. Indeed, some 91 % of human otoacariasis cases in Sri Lanka were due to infestation by D. auratus. With the propensity of this tick to feed on multiple species of hosts, including humans, and the detection of pathogenic bacteria and viruses from this tick, D. auratus is a tick of medical, veterinary, and indeed zoonotic concern. The geographic range of this tick, however, is not well known. Therefore, in the present paper, we used the species distribution model, BIOCLIM, to project the potential geographic range of D. auratus, which may aid pathogen and tick-vector surveillance. We showed that the potential geographic range of D. auratus is far wider than the current geographic distribution of this tick, and that regions in Africa, and in North and South America seem to have suitable climates for D. auratus. Interestingly, in Southeast Asia, Borneo and Philippines also have suitable climates for D. auratus, but D. auratus has not been found in these regions yet despite the apparent close proximity of these regions to Mainland Southeast Asia, where D. auratus occurs. We thus hypothesize that the geographic distribution of D. auratus is largely dependent on the movement of wild pigs and whether or not these wild pigs are able to overcome dispersal barriers. We also review the potential pathogens and the diseases that may be associated with D. auratus and provide an updated host index for this tick.

Control of Rhipicephalus microplus on taurine cattle with fluralaner in a subtropical region.

BACKGROUND: In Rio Grande do Sul, Brazil, a region with a subtropical climate, Rhipicephalus microplus is present in taurine cattle raised for beef and milk. In addition, ticks resistant to multiple acaricides are present in this region. Recently, fluralaner (isoxazoline) was launched on the market. Thus, there is a need to evaluate the effects of fluralaner for the control of R. microplus on taurine cattle. In addition, occurrence of myiasis by Cochliomyia hominivorax larvae after tick parasitism and weight gain of cattle during the experimental period were evaluated. METHODS: Thirty naturally infested cattle were divided into two experimental groups: T01, treated with fluralaner (2.5 mg/kg) pour-on; T02, control. T01 received fluralaner on Days 0 (early summer in January), 42 and 84 (early autumn), whereas T02, a control group, received palliative treatment with a spray formulation when the group mean was ≥ 30 ticks. Counts of R. microplus females and calculation of the efficacy of fluralaner were performed on Days 3, 7, 14, 28, 35, 42, 56, 70, 84, 98, 112 and 126. The occurrence of myiasis was assessed throughout the study period. In addition, the weight, weight gain and daily weight gain of the animals were evaluated. RESULTS: In the 12 evaluations performed, the parasitic load of T01 was near zero. Fluralaner showed 99.5% efficacy on the 3rd day after the first treatment and 100% efficacy from Day 7 to Day 126. Cochliomyia hominivorax larvae (n = 6; p = 0.0251) were found only in the control group (T02). At the end of the study, the animals subjected to treatments with fluralaner gained 32.8 kg more than the animals in the control group. CONCLUSIONS: Application of fluralaner in summer and autumn, with 42-day intervals between treatments, was effective to control R. microplus on taurine cattle, which also gained more weight than control cattle. Additionally, no cases of myasis were documented in animals treated with fluralaner.

Enzootic stability of tick fever in Holstein calves grazing in a tropical region, subjected to strategic cattle tick control with fluralaner.

BACKGROUND: In 2022, fluralaner was launched on the market for use in the control of the cattle tick Rhipicephalus microplus after showing 100% efficacy in registration trials against the causative agents of cattle tick fever (TFAs). The aim of the present study was to determine whether a strategic control regimen against R. microplus using fluralaner (FLU) in Holstein calves grazing in a tropical region would alter the enzootic stability status of cattle tick fever, triggering outbreaks in these animals up to 22 months age. METHODS: In this study, a group of calves treated with FLU was compared with a control group treated with the regimen currently being used on the farm, which consisted of the fipronil + fluazuron formulation (FIFLUA). In the first experiment, the efficacy of the FIFLUA pour-on formulation was evaluated in a field study. In the second experiment, which lasted 550 days, two experimental groups (n = 30/group) of Holstein calves naturally infested with R. microplus were analyzed. Calves aged 4 to 10 months received either a specific treatment regimen with FLU (experimental group) or FIFLUA (control group). During this period, tick counts, animal weight measurement, feces collection (to determine eggs and oocysts per gram of feces), tick fever monitoring, blood smears (to ascertain enzootic stability of the herd), PCR testing for TFAs and serology (indirect enzyme-linked immunosorbent assay [iELISA]) were performed. All calves were evaluated for signs of tick fever between ages 11 and 22 months. RESULTS: FIFLUA showed an acaricidal efficacy of > 90% from post-treatment days 14 to 35. Regarding treatments against the TFAs, the average number of treatments was similar between groups, but animals treated with FLU had a smaller reduction in packed cell volume on some of the evaluation dates of the second and third treatment against TFAs. In calves aged 10 months in the FLU group, B. bovis was not detected by PCR (0/15 samples), 40% of the samples had antibody titers and 33% (10/30) of the samples had positive blood smears. Regarding B. bigemina, > 86% of the samples in both groups tested positive for B. bigemina DNA and antibodies; there was no difference in the antibody titers between the groups. There were no clinical cases of cattle tick fever in calves aged 11 to 22 months. CONCLUSIONS: In comparison with the control treatment, the strategic control regimen against R. microplus with FLU that was implemented in the present study did not negatively affect the enzootic stability status of A. marginale and B. bigemina in the herd up to 22 months of age. The enzootic stability status of B. bovis was not reached by either group. These results likely represent a characteristic of the local tick population, so further studies should be performed.

Investigations of the tick burden on passeriform, water-associated and predatory birds reveal new tick-host associations and habitat-related factors of tick infestation.

BACKGROUND: Previous studies on the tick infestation of birds in the Carpathian Basin focused on songbirds (Passeriformes). Thus, the primary aim of the present work was to extend the scope of previous studies, i.e. to include aquatic (water-associated) bird species in a similar context, especially considering that these birds are usually long-distance migrants. METHODS: Between March 2021 and August 2023, 11,919 birds representing 126 species were checked for the presence of ticks. From 352 birds belonging to 40 species, 905 ixodid ticks were collected. Tick species were identified morphologically and/or molecularly. RESULTS: Ticks from avian hosts belonged to seven species: Ixodes ricinus (n = 448), I. frontalis (n = 31), I. festai (n = 2), I. arboricola (n = 36), I. lividus (n = 4), Haemaphysalis concinna (n = 382) and Dermacentor reticulatus (n = 2). Nymphs of I. ricinus occurred with a single activity peak around March-May, whereas its larvae typically infested birds in May, June or July. By contrast, H. concinna usually had its activity maximum during the summer (nymphs in June-July, larvae later in July-August). Interestingly, two ornithophilic species, I. frontalis and I. arboricola, were most active around winter months (between October and April). A significantly lower ratio of aquatic birds was found tick-infested than songbirds. Several new tick-host associations were revealed, including I. ricinus from Greylag Goose (Anser anser) and D. reticulatus from Great Egret (Ardea alba) and Sedge Warbler (Acrocephalus schoenobaenus). Ticks were collected for the first time in Europe from two species of predatory birds as well as from Little Bittern (Ixobrychus minutus). Bird species typically inhabiting reedbeds were most frequently infested with H. concinna, and most ticks localized at their throat, as opposed to forest-dwelling avian hosts, on which I. ricinus predominated and ticks were more evenly distributed. CONCLUSIONS: In the evaluated region, aquatic birds appear to be less important in tick dispersal than songbirds. However, newly revealed tick-host associations in this category attest to their hitherto neglected contribution. The results suggest that the habitat type will have significant impact not only on the species composition but also on the feeding location of ticks on birds.

Identification and distribution of Rhipicephalus microplus in selected high-cattle density districts in Uganda: signaling future demand for novel tick control approaches.

BACKGROUND: Rhipicephalus (Boophilus) microplus (Canestrini, 1888), the Asian blue tick, is a highly invasive and adaptable ectoparasite. This tick species has successfully established itself in most regions of the world, with movement of cattle being a major driver for its spread. In the recent past, R. microplus ticks have been reported in three districts of Uganda. Information on its spread and distribution are vital in deepening our understanding of the ecological scenarios that lead to tick persistence and in the formulation of control strategies. This is especially important in the cattle-dense districts. METHODS: We randomly collected tick specimens from 1,461cattle spread across seven cattle dense districts located in the Central, Karamoja and West Nile regions of Uganda from January to September 2020. The ticks were identified using standard morpho-taxonomic keys and the R. microplus tick species identities were confirmed by sequencing of the ITS2 region, 12S rRNA and 16S rRNA genes and phylogenetic analyses. RESULTS: Adult ticks (n = 13,019) were collected from 1,461 cattle. Seventeen tick species were identified based on morpho-taxonomic keys and the majority (47.4%; n=6184) of these were R. appendiculatus. In total, 257 R. microplus ticks were found infesting cattle in 18 study sites in the districts of Amudat, Kaabong, Napak (Karamoja region) and Arua (West Nile region). The identity of R. microplus was confirmed using molecular technics. No R. microplus tick was recorded in the districts of Lyantonde and Nakaseke (Central region). Arua district accounted for 82.1% (n=211) of the R. microplus ticks recorded followed by Napak district at 16.3% (n=42), while Amudat and Kaabong districts accounted for 1.5% (n=4). Rhipicephalus microplus and R. decoloratus co-existed in 6 of the 13 study sites in Arua district, while in another 6 study sites, no R. decoloratus was recorded. In the Karamoja region districts R. decoloratus co-existed with R.microplus. Of the total 618 ticks belonging to four species of the subgenus Boophilus recorded in this study, R. decoloratus accounted for 50.04% (n=334), followed by R. microplus at 41.58% (n=257), R. geigyi at 2.75% (n=17) and R. annulatus at 1.61% (n=10). In the districts of Amudat, Kaabong and Napak, R. decoloratus was more dominant (76.1%; n=179) of the three Rhipicephalus (Boophilus) tick species recorded, followed by R. microplus (19.5%; n=46) and R. geigyi (4.2%; n=10). Contrariwise, R. microplus was more dominant (84%; n=211) in Arua district followed by R. decoloratus (10.7%; n=27), R. annulatus (3.9%; n=10) and R. geigyi (1.1%; n=3). Phylogenetic analyses of the ITS2 region, 12S rRNA and 16S rRNA genes revealed subgrouping of the obtained sequences with the previously published R. microplus sequences from other parts of the world. CONCLUSION: Rhipicephalus microplus ticks were found infesting cattle in four districts of Uganda. The inability to find R. decoloratus, an indigenous tick, from six sites in the district of Arua is suggestive of its replacement by R. microplus. Rhipicephalus microplus negatively affects livestock production, and therefore, there is a need to determine its distribution and to deepen the understanding of the ecological factors that lead to its spread and persistence in an area.

The complete mitochondrial genome of cattle tick clade C reveals the genetic relationship within Rhipicephalus microplus complex.

Cattle ticks (Rhipicephalus microplus) are important economic ectoparasites causing direct and indirect damage to cattle and leading to severe economic losses in cattle husbandry. It is common knowledge that R. microplus is a species complex including five clades; however, the relationships within the R. microplus complex remain unresolved. In the present study, we assembled the complete mitochondrial genome of clade C by next-generation sequencing and proved its correctness based on long PCR amplification. It was 15,004 bp in length and consisted of 13 protein genes, 22 transfer genes, and two ribosomal genes located in the two strains. There were two copies of the repeat region (pseudo-nad1 and tRNA-Glu). Data revealed that cox1, cox2, and cox3 genes were conserved within R. microplus with small genetic differences. Ka/Ks ratios suggested that 12 protein genes (excluding nad6) may be neutral selection. The genetic and phylogenetic analyses indicated that clade C was greatly close to clade B. Findings in the current study provided more data for the identification and differentiation of the R. microplus complex and made up for the lack of information about R. microplus clade C.

Grazing system and Hyalomma marginatum tick infestation in cattle with high prevalence of SFG Rickettsia spp.

Tick-borne diseases (TBDs) represent a significant portion of infectious diseases of global public health interest. In Italy, knowledge about the occurrence of tick-borne pathogens (TBPs) in ticks parasitizing cattle is scarce. In this research, we focused on ticks infesting Maremmana cattle grazing in open pasture and silvopasture systems. After being morphologically identified, ticks were molecularly tested for the presence of pathogens of the genus Rickettsia. Of the 794 ticks detected, 117 were collected, being the majority Hyalomma marginatum (72.6%), followed by other Hyalomma species (23%), Rhipicephalus turanicus (1.7%), Rh. bursa (0.9%), Hy. lusitanicum (0.9%) and Dermatocentor marginatus (0.9%). All ticks were adults, 58.1% males and 41.8% females. The highest tick prevalence was noted in April for silvopasture system cattle (90%), and in May for open pasture ones (85%). TBPs were detected only in Hy. marginatum, and all belong to Rickettsia spp. of zoonotic interest. In particular, 21/40 (52.5%) ticks scored positive for Rickettsia spp. by gltA gene and of these 15/21 (71.4%) also to spotted fever group (SFG) rickettsiae by ompA gene. Of the total positive specimens, 19 were successfully sequenced and scored Rickettsia aeschilimannii (17/19, 89.5%), R. slovaca (1/19, 5%), and R. massiliae (1/19, 5%). This research highlights the potential impact of grazing systems on cattle parasitization by hard ticks. The molecular investigation of TBPs in ticks collected from Maremmana cattle shed light on the presence of pathogenic bacteria of SFG Rickettsia spp., pointing out the potential risk of TBPs transmission between livestock and humans.