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Buffalo-derived Theileria parva can 'break through' the immunity induced by the infection and treatment vaccination method (ITM) in cattle. However, no such 'breakthroughs' have been reported in northern Tanzania where there has been long and widespread ITM use in pastoralist cattle, and the Cape buffalo (Syncerus caffer) is also present. We studied the exposure of vaccinated and unvaccinated cattle in northern Tanzania to buffalo-derived T. parva using p67 gene polymorphisms and compared this to its distribution in vaccinated cattle exposed to buffalo-derived T. parva in central Kenya, where vaccine 'breakthroughs' have been reported. Additionally, we analysed the CD8+ T cell target antigen Tp2 for positive selection. Our results showed that 10% of the p67 sequences from Tanzanian cattle (n = 39) had a buffalo type p67 (allele 4), an allele that is rare among East African isolates studied so far. The percentage of buffalo-derived p67 alleles observed in Kenyan cattle comprised 19% of the parasites (n = 36), with two different p67 alleles (2 and 3) of presumptive buffalo origin. The Tp2 protein was generally conserved with only three Tp2 variants from Tanzania (n = 33) and five from Kenya (n = 40). Two Tanzanian Tp2 variants and two Kenyan Tp2 variants were identical to variants present in the trivalent Muguga vaccine. Tp2 evolutionary analysis did not show evidence for positive selection within previously mapped epitope coding sites. The p67 data indicates that some ITM-vaccinated cattle are protected against disease induced by a buffalo-derived T. parva challenge in northern Tanzania and suggests that the parasite genotype may represent one factor explaining this. [ABSTRACT FROM AUTHOR]

Background Culicoides spp. play an important role in the transmission of several vector-borne pathogens such as Bluetongue and Schmallenberg virus in Europe. To better understand the biology of local Culicoides species, a study divided into three parts was performed in northeast Germany to elucidate the feeding activity patterns (study A), preferential landing and feeding sites (study B) and host feeding preferences (study C) of Culicoides spp. using cattle and sheep as baits. Methods In study A, the activity of Culicoides spp. was monitored over a 72 h period by collecting insects at regular intervals from the interior of drop traps with cattle or sheep standing inside. In study B, Culicoides spp. were directly aspirated from the coat and fleece of cattle and sheep during the peak activity period of Culicoides. In study C, Culicoides spp. were collected using drop traps with either cattle or sheep standing inside and located 10 m apart. Results In study A, 3,545 Culicoides midges belonging to 13 species were collected, peak activity was observed at sunset. In study B, 2,024 Culicoides midges were collected. A significantly higher number of midges was collected from the belly and flank of cattle in comparison to their head region. In study C, 3,710 Culicoides midges were collected; 3,077 (83%) originated from cattle and 633 (17%) from sheep. Nearly half (46.7%) of the midges collected from cattle were engorged, significantly more than the number of engorged midges collected from sheep (7.5%). Culicoides from the Obsoletus complex (C. obsoletus and C. scoticus) were the most common Culicoides species encountered, followed by C. punctatus. Other species identified were C. dewulfi, C. chiopterus, C. pulicaris, C. lupicaris, C. pallidicornis, C. subfascipennis, C. achrayi, C. stigma, C. griseidorsum and C. subfagineus, the last two species are reported for the first time in Germany. Engorged C. chiopterus were collected in relatively high numbers from sheep, suggesting that this species may have a preference for sheep. Conclusions An insight into the feeding behaviour of local Culicoides species under field conditions in northeast Germany was obtained, with implications for the implementation of control measures and midge-borne disease risk analysis. [ABSTRACT FROM AUTHOR]

Background: Rhipicephalus (Boophilus) spp. ticks economically impact on cattle production in Africa and other tropical and subtropical regions of the world. Tick vaccines constitute a cost-effective and environmentally friendly alternative to tick control. The R. microplus Bm86 protective antigen has been produced by recombinant DNA technology and shown to protect cattle against tick infestations. Results: In this study, the genes for Bm86 (R. microplus), Ba86 (R. annulatus) and Bd86 (R. decoloratus) were cloned and characterized from African or Asian tick strains and the recombinant proteins were secreted and purified from P. pastoris. The secretion of recombinant Bm86 ortholog proteins in P. pastoris allowed for a simple purification process rendering a final product with high recovery (35-42%) and purity (80-85%) and likely to result in a more reproducible conformation closely resembling the native protein. Rabbit immunization experiments with recombinant proteins showed immune cross-reactivity between Bm86 ortholog proteins. Conclusion: These experiments support the development and testing of vaccines containing recombinant Bm86, Ba86 and Bd86 secreted in P. pastoris for the control of tick infestations in Africa. [ABSTRACT FROM AUTHOR]

To address the lack of information on ticks infesting cattle in Egypt and the pathogens that they transmit, the current study aimed to (i) provide insight into tick species found on cattle in Egypt, (ii) identify the pathogens in ticks and their cattle hosts and (iii) detect pathogen associations in ticks and cattle. Tick samples and blood from their bovine hosts were collected from three different areas in Egypt (EL-Faiyum Oasis, Assiut Governorate and EL-Kharga Oasis). Tick species were identified by morphology and by sequence analysis of the cytochrome C oxidase subunit 1 (cox1) gene. Tick pools and blood samples from cattle were screened by the Reverse Line Blot hybridization (RLB) assay for the simultaneous detection of tick-borne pathogens, including Babesia , Theileria, Anaplasma , Ehrlichia , and Rickettsia spp., as well as the tick endosymbiont Midichloria mitochondrii. The RLB results were confirmed with specific conventional and semi-nested PCRs followed by sequencing. In total, 570 ticks (males, females and nymphs) were collected from 41 heads of cattle. Altogether 398 ticks belonged to the genus Hyalomma (397 Hyalomma excavatum and one Hyalomma scupense) while 172 ticks were identified as Rhipicephalus annulatus. Pooled H. excavatum ticks tested positive for several protozoa and bacteria with different minimum infection rates (MIRs): Theileria annulata (18.1 %) , Babesia occultans (1.8 %) , Anaplasma marginale (28.5 %) , Anaplasma platys (0.25 %), Midichloria mitochondrii (11.6 %) , Ehrlichia chaffeensis -like (1.8 %) and Ehrlichia minasensis (1 %). In R. annulatus, several agents were identified at different MIRs: T. annulata (2.3 %), B. bovis (0.6 %), A. marginale (18.0 %), A. platys (1.2 %), M. mitochondrii (2.9 %), E. minasensis (0.6 %). Pathogens co-detection in tick pools revealed A. marginale and T. annulata in 13.3 % samples followed by the co-detection of A. marginale and M. mitochondrii (8.4 %). In addition, triple co-detection with A. marginale, T. annulata and M. mitochondrii were found in 5.3 % of the tick pools. In cattle, the most common coinfection was with A. marginale and T. annulata (82.9 %) followed by the coinfection between A. marginale, T. annulata and B. bovis (4.9 %), A. marginale and B. bigemina (2.4 %) and finally the coinfection between T. annulata and B. occultans (2.4 %). Anaplasma platys, Babesia occultans, and E. minasensis were detected for the first time in Egypt in both cattle and ticks. These findings should be taken in consideration regarding human and animal wellbeing by the public health and veterinary authorities in Egypt. [ABSTRACT FROM AUTHOR]