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Ticks are pivotal in transmitting a variety of pathogens that affect both humans and animals. These pathogens often occur in guilds, groups of species that exploit similar resources in similar ways. Although the composition of tick‐borne pathogen (TBP) guilds is well‐documented, the interactions among pathogens within these guilds remain poorly understood. We hypothesized that abiotic and biotic factors significantly influence the patterns of occurrence and interactions among pathogens within these guilds. To investigate this, we analyzed microfluidic‐based high‐throughput data on microorganisms from 166 Hyalomma excavatum ticks (94 male and 72 female) collected across different seasons from cattle in the central Algerian steppe using network analysis to uncover complex pathogen–pathogen interaction patterns. We found that female ticks had a higher infection rate (63.9%) with common pathogens such as Rickettsia slovaca (26.4%), unclassified Apicomplexa (22.2%), and Borrelia afzelii (19.4%). Male ticks showed a 56.4% infection rate, with Rickettsia (31.1%) and R. slovaca (16%) being the most prevalent. Notable pathogen–pathogen interactions within guilds were identified, with positive associations such as between R. slovaca and Rickettsia conorii in males, and B. afzelii and Borrelia spielmanii in females, indicating cooperative interactions. Conversely, negative associations, such as between Anaplasma phagocytophilum and Francisella tularensis, suggested competitive exclusion. The observed variation in interaction patterns under different conditions indicates that ecological determinants, both biotic and abiotic, influence pathogen association dynamics within guilds. These findings have significant implications for understanding disease transmission and developing control strategies. [ABSTRACT FROM AUTHOR]

Research into various bacterial pathogens that can be transmitted between different animals and may have zoonotic potential has led to the discovery of different strains of Bartonella sp. in bats and their associated ectoparasites. Despite their enormous species diversity, only a few studies have focussed on the detection of bacterial pathogens in insectivorous bats of boreal forests and their associated Macronyssidae and Spinturnicidae mites. We collected and molecularly analysed mite samples from forest‐dwelling bat species distributed all along the boreal belt of the Palearctic, from Central Europe to Far East. Ectoparasitic mites were pooled for DNA extraction and DNA amplification polymerase chain reaction (PCRs) were conducted to detect the presence of various bacterial (Anaplasmataceae, Bartonella sp., Rickettsia sp., Mycoplasma sp.) and protozoal (Hepatozoon sp.) pathogens. Bartonella sp. DNA was detected in four different mite species (Macronyssidae: Steatonyssus periblepharus and Spinturnicidae: Spinturnix acuminata, Sp. myoti and Sp. mystacinus), with different prevalences of the targeted gene (gltA, 16‐23S ribosomal RNA intergenic spacer and ftsZ). Larger pools (>5 samples pooled) were more likely to harbour Bartonella sp. DNA, than smaller ones. In addition, cave‐dwelling bat hosts and host generalist mite species are more associated with Bartonella spp. presence. Spinturnicidae mites may transmit several distinct Bartonella strains, which cluster phylogenetically close to Bartonella species known to cause diseases in humans and livestock. Mites with ubiquitous presence may facilitate the long‐term maintenance (and even local recurrence) of Bartonella‐infestations inside local bat populations, thus acting as continuous reservoirs for Bartonella spp in bats. [ABSTRACT FROM AUTHOR]

In recent years, significant changes have been observed in the distribution and abundance of local Dermacentor reticulatus populations. However, changes in D. reticulatus dynamics have not been studied in southeastern Poland. Our objective was to enhance our understanding of the environmental factors influencing the occurrence and density of D. reticulatus in this area. Additionally, we sought to investigate the genetic diversity of the tick population and the prevalence of tick-borne pathogens (TBPs). To this end, we established 45 study sites in the Subcarpathian province. Ticks were collected during their peak activity in both spring and autumn. A subset of randomly selected specimens underwent molecular analysis for TBPs screening, using high-throughput microfluidic real-time PCR. Positive amplicons were then sequenced, and phylogenetic analyses were conducted. Our findings confirmed the presence of D. reticulatus ticks in 24 surveyed sites, primarily concentrated in the northern and eastern parts of the region. The mean density of D. reticulatus ticks in their compact range was 5.8 ± 6.4 specimens/100 m2. Notably, air temperature and altitude emerged as significant factors influencing the species' activity. We also identified a high prevalence of Rickettsia raoultii infections in adult D. reticulatus, reaching up to 84.21%. Additionally, 9.52% of ticks were found to be infected with R. helvetica and 4.76% with Anaplasma phagocytophilum. Furthermore, our genetic analyses confirmed the identity of D. reticulatus in the Subcarpathian region, aligning with haplotypes found in other regions of Poland, Czechia, Croatia, and Portugal. In conclusion, our study suggests that the surveyed region represents the current boundary of the compact range of D. reticulatus in Poland in which this tick species exhibits low genetic diversity and a narrow spectrum of detected TBPs. [ABSTRACT FROM AUTHOR]

Tick-borne diseases affecting domestic animals and humans have increased globally in recent years. Pakistan, in particular, faces a significant economic threat from ticks, where two specific species, Rhipicephalus microplus and Hyalomma anatolicum, act as vectors for various pathogens such as piroplasma, Anaplasma, Ehrlichia, and Rickettsia that pose a significant burden on livestock production in the country. To better understand the risk that tick-borne pathogens (TBPs) pose to livestock in Pakistan, we conducted a cross-sectional study of the occurrence, diversity, and coinfection of these pathogens in small and large ruminants owned by small farms as well as in ticks collected from these animals. We collected blood samples from 224 cattle, 224 buffalo, 69 goats, and 56 sheep, gathered from 112 farms located in seven districts of Punjab, one of Pakistan's largest province. In addition, we collected a total of 476 ticks attached to these animals. Based on the identification of tick species through morphology and sequence analysis of the 16S rRNA and cytochrome c oxidase subunit 1 (cox1) gene, we confirmed that the most commonly collected tick species were Rh. microplus (38.65% of all individuals), H. anatolicum (31.93%), and Rh. decoloratus (8.40%). Notable pathogens detected in the collected ticks included Theileria annulata (18.4% prevalence), Anaplasma ovis (15.79%), A. centrale (13.16%), and Rickettsia slovaca (13.16%). In blood samples, the most frequently detected pathogens were T. annulata (n = 8), Babesia bovis (n = 7), A. centrale (n = 6), and B. bigemina (n = 5). In some cases, both cattle and buffaloes were found to be coinfected with B. bovis, T. annulata, and A. centrale. These findings provide valuable insights into the circulation of TBPs in livestock and highlight the need for further research on the epidemiological risk that these pathogens pose to ruminants in Pakistan. [ABSTRACT FROM AUTHOR]

Most tick‐borne pathogens (TBPs) are secondarily acquired by ticks during feeding on infected hosts, which imposes 'priority effect' constraints, as arrival order influences the establishment of new species in a microbial community. Here we tested whether once acquired, TBPs contribute to bacterial microbiota functioning by increasing community stability. For this, we used Hyalomma marginatum and Rhipicephalus bursa ticks collected from cattle in different locations of Corsica and combined 16S rRNA amplicon sequencing and co‐occurrence network analysis, with high‐throughput pathogen detection, and in silico removal of nodes to test for impact of rickettsial pathogens on network properties. Despite its low centrality, Rickettsia showed preferential connections in the networks, notably with a keystone taxon in H. marginatum, suggesting facilitation of Rickettsia colonisation by the keystone taxon. In addition, conserved patterns of community assembly in both tick species were affected by Rickettsia removal, suggesting that privileged connections of Rickettsia in the networks make this taxon a driver of community assembly. However, Rickettsia removal had minor impact on the conserved 'core bacterial microbiota' of H. marginatum and R. bursa. Interestingly, networks of the two tick species with Rickettsia have similar node centrality distribution, a property that is lost after Rickettsia removal, suggesting that this taxon drives specific hierarchical interactions between bacterial microbes in the microbiota. The study indicates that tick‐borne Rickettsia play a significant role in the tick bacterial microbiota, despite their low centrality. These bacteria are influential and contribute to the conservation of the 'core bacterial microbiota' while also promoting community stability. [ABSTRACT FROM AUTHOR]

The effect of pancreatic exocrine insufficiency (PEI) on protein malabsorption is little documented, partly due to methodological barriers. We aimed to validate biomarkers of protein malabsorption using a 15N test meal in a minipig model of PEI. Six pancreatic duct-ligated minipigs were used as a model of PEI and four nonoperated animals as a control. All animals were equipped with an ileocecal reentrant cannula. Minipigs were given a test meal containing [15N]casein. The PEI animals repeated the test three times, in the absence of any pancreatic enzymes, or after pancreatic substitution at two levels [A or B: 7,500 or 75,000 (lipase) and 388 or 3881 (protease) FIP U]. Ileal chyme, urine, and blood were collected postprandially. Nitrogen and 15N were measured in digestive and metabolic pools. We obtained a gradient of ileal protein digestibility from 29 ± 11% in PEI to 89 ± 6% in the controls and a dosedependent response of enzymes. Insulin and gastric inhibitory polypeptide secretions were decreased by PEI, an effect that was counteracted with the enzymes at level B. The total recovery of 15N in urinary urea and plasma proteins was 14 ± 5.1% in the control group and decreased to 5.5 ± 2.1% by PEI. It was dose dependently restored by the treatment. Both 15N recovery in plasma and urine were correlated to protein digestibility. We confirm that the 15N transfer in those pools is a sensitive marker of protein malabsorption. Nevertheless, an optimization of the test meal conditions would be necessary in the view of implementing a clinical test. NEW & NOTEWORTHY We designed an intervention study to create a gradient of ileal protein digestibility in minipigs with pancreatic exocrine insufficiency and to validate reliable metabolic markers using a 15N oral meal test. 15N recovery in plasma proteins and to a higher extent in urine was sensitive to protein malabsorption. This test is minimally invasive and could be used to reveal protein malabsorption in patients. [ABSTRACT FROM AUTHOR]

The effect of pancreatic exocrine insufficiency (PEI) on protein malabsorption is little documented, partly due to methodological barriers. We aimed to validate biomarkers of protein malabsorption using a 15 N test meal in a minipig model of PEI. Six pancreatic duct-ligated minipigs were used as a model of PEI and four nonoperated animals as a control. All animals were equipped with an ileocecal reentrant cannula. Minipigs were given a test meal containing [ 15 N]casein. The PEI animals repeated the test three times, in the absence of any pancreatic enzymes, or after pancreatic substitution at two levels [ A or B: 7,500 or 75,000 (lipase) and 388 or 3881 (protease) FIP U]. Ileal chyme, urine, and blood were collected postprandially. Nitrogen and 15 N were measured in digestive and metabolic pools. We obtained a gradient of ileal protein digestibility from 29 ± 11% in PEI to 89 ± 6% in the controls and a dose- dependent response of enzymes. Insulin and gastric inhibitory polypeptide secretions were decreased by PEI, an effect that was counteracted with the enzymes at level B. The total recovery of 15 N in urinary urea and plasma proteins was 14 ± 5.1% in the control group and decreased to 5.5 ± 2.1% by PEI. It was dose dependently restored by the treatment. Both 15 N recovery in plasma and urine were correlated to protein digestibility. We confirm that the 15 N transfer in those pools is a sensitive marker of protein malabsorption. Nevertheless, an optimization of the test meal conditions would be necessary in the view of implementing a clinical test. NEW & NOTEWORTHY We designed an intervention study to create a gradient of ileal protein digestibility in minipigs with pancreatic exocrine insufficiency and to validate reliable metabolic markers using a 15 N oral meal test. 15 N recovery in plasma proteins and to a higher extent in urine was sensitive to protein malabsorption. This test is minimally invasive and could be used to reveal protein malabsorption in patients.