The Experts below are selected from a list of 222 Experts worldwide ranked by ideXlab platform
W. Reuben Kaufman - One of the best experts on this subject based on the ideXlab platform.
-
Cuticle expansion during feeding in the tick Amblyomma hebraeum (Acari: Ixodidae): The role of hydrostatic pressure.
Journal of insect physiology, 2016Co-Authors: W. Reuben Kaufman, Susan E. Kaufman, Peter C. FlynnAbstract:Female Amblyomma hebraeum ticks (Acari: Ixodidae) increase their weight ∼10-fold during a 'slow phase of engorgement' (7-9 days), and a further 10-fold during the 'rapid phase' (12-24h). During the rapid phase, the cuticle thins by half, with a plastic (permanent) deformation of greater than 40% in two orthogonal directions. A stress of 2.5 MPa or higher is required to achieve this degree of deformation (Flynn and Kaufman, 2015). Using a dimensional analysis of the tick body and applying the Laplace equation, we calculated that the tick must achieve high internal hydrostatic pressures in order to engorge fully: greater than 55 kPa at a fed:unfed mass ratio of ∼20:1, when cuticle thinning commences (Flynn and Kaufman, 2011). In this study we used a telemetric pressure transducer system to measure the internal hydrostatic pressure of ticks during feeding. Sustained periods of irregular high frequency (>20 Hz) pulsatile bursts of high pressure (>55 kPa) were observed in two ticks: they had been cannulated just prior to the rapid phase of engorgement, and given access to a host rabbit for completion of the feeding cycle. The pattern of periods of high pressure generation varied over the feeding cycle and between the two specimens. We believe that these pressures exceed those reported so far for any other animal.
-
Mechanical properties of the cuticle of the tick Amblyomma hebraeum (Acari: Ixodidae).
The Journal of experimental biology, 2015Co-Authors: Peter C. Flynn, W. Reuben KaufmanAbstract:Female ticks of the family Ixodidae increase their mass up to 100-fold during the 7-10 day feeding period. We determined the material properties of the alloscutal cuticle of female Amblyomma hebraeum from the time of moulting through to full engorgement. The material properties of the cuticle were evaluated by a Kelvin-Voigt analysis of compliance determined from the stretch of loops of cuticle under stress. There was a 3-fold increase in cuticle dry mass during the first 3 weeks post-moult, during which the ductility and stiffness of the cuticle increased substantially. Under stress, the cuticle displayed time-dependent stretch, with a plastic (non-recoverable) and viscoelastic (recoverable) component. Plastic deformation was reasonably constant in the range 10-15% over a wide range of induced stress above ∼ 0.6 MPa. The plastic component of tick alloscutal cuticle was about 5-10 times higher than that of unsclerotized insect cuticle. Tick cuticle is far more ductile than unsclerotized insect cuticle. Material properties of the cuticle did not change significantly as a function of cuticular water content over the normal range throughout the feeding cycle (13-37% wet mass). Injected dopamine (DA) reduced one measure of the viscosity of the cuticle by 38%. Plastic deformability of the cuticle was reduced by 70% after an in vitro stretch, but restored in fully engorged ticks, and in in vitro stretched loops by treatment with DA and reduced pH. Thinning of the cuticle by half during the rapid phase of engorgement requires plastic deformation (irreversible strain) in two orthogonal dimensions in excess of 40%. Treatment with DA increased plastic deformation and enabled extensibility (strain at the point of rupture) above 40%.
-
Mechanical properties of the cuticle of the tick, Amblyomma hebraeum (Acari: Ixodidae)
Journal of Experimental Biology, 2015Co-Authors: Peter C. Flynn, W. Reuben KaufmanAbstract:Female ticks of the family Ixodidae increase their weight up to 100-fold during the 7-10 day feeding period. We determined the material properties of the alloscutal cuticle of female Amblyomma hebraeum from the time of moulting through full engorgement. The material properties of the cuticle were evaluated by a Kelvin-Voigt analysis of compliance determined from the stretch of loops of cuticle under stress. There was a 3-fold increase in cuticle dry weight during the first 3 weeks post moult, during which the ductility and stiffness of the cuticle increased substantially. Under stress, cuticle displayed time-dependent stretch, with a plastic (non-recoverable) and viscoelastic (recoverable) component. Plastic deformation was reasonably constant in the range of 10 to 15% over a wide range of induced stress above ∼0.6 MPa. The plastic component of tick alloscutal cuticle was about five to ten times higher than that of unsclerotized insect cuticle. Tick cuticle is also far more ductile than unsclerotized insect cuticle. Material properties of the cuticle did not change significantly as a function of cuticular water content over the normal range throughout the feeding cycle (13-37% wet weight). Injected dopamine (DA) reduced one measure of the viscosity of cuticle by 38%. Plastic deformability of cuticle was reduced by 70% after an in vitro stretch, but restored in fully engorged ticks, and in in-vitro stretched loops by treatment with DA and reduced pH. Thinning of cuticle by half during the rapid phase of engorgement requires plastic deformation (irreversible strain) in two orthogonal dimensions in excess of 40%. Treatment with DA increased plastic deformation and enabled extensibility (strain at the point of rupture) above 40%.
-
Molecular characterization of two vitellogenin genes from the tick, Amblyomma hebraeum (Acari: Ixodidae)
Ticks and tick-borne diseases, 2014Co-Authors: Alexander D. Smith, W. Reuben KaufmanAbstract:We have identified full-length cDNAs encoding two vitellogenins (Vg) from the African bont tick Amblyomma hebraeum Koch (1844). Vg is a large storage protein that is the precursor to vitellin (Vn), the major yolk protein found in eggs. The first Vg cDNA is 5866 bp long, with a 5715 bp reading frame encoding a 1904 amino acid protein. The second Vg cDNA is 5963 bp long, with a 5781 open reading frame encoding a 1926 amino acid protein. Both proteins possess a short N-terminal signal peptide of 21 and 16 amino acids respectively, which following cleavage result in 213.8 kDa Vg1 and 215.9 kDa Vg2 proteins. The conceptual amino acid translations for both proteins show the N-terminal lipid binding domain, the internal DUF1943 domain and the C-terminal von Willebrand factor type D domain common to all other known Vgs. In addition, these sequences do not resemble any of the conserved sequences that are the hallmarks of the highly similar tick storage protein (carrier protein; CP). Phylogenetic analysis indicates that the Vgs isolated in this study cluster together with other tick Vgs. Using RT-PCR, both Vg1 and Vg2 were expressed only in mated females, and only after they had fed to repletion. In situ hybridizations indicated that both Vgs were expressed only in the midgut and fat body of these females, and was not present in any other female tissues, nor in either fed or unfed males.
-
Molecular characterization of the vitellogenin receptor from the tick, Amblyomma hebraeum (Acari: Ixodidae).
Insect biochemistry and molecular biology, 2013Co-Authors: Alexander D. Smith, W. Reuben KaufmanAbstract:Abstract We have identified the full-length cDNA encoding a vitellogenin receptor (VgR) from the African bont tick Amblyomma hebraeum Koch (1844). VgRs are members of the low-density lipoprotein receptor superfamily that promote the uptake of the yolk protein vitellogenin (Vg), from the haemolymph. The AhVgR (GenBank accession No. JX846592 ) is 5703 bp, and encodes an 1801 aa protein with a 196.5 kDa molecular mass following cleavage of a 22 aa signal peptide. Phylogenetic analysis indicates that AhVgR is highly similar to other tick VgRs. AhVgR is expressed in only the ovary of mated, engorged females, and is absent in all other female tissues and in both fed and unfed males. Unfed, adult females injected with a VgR-dsRNA probe to knock-down VgR expression experienced a significant delay in ovary development and started oviposition significantly later than controls. These results indicate that the expression of AhVgR is important for the uptake of Vg and subsequent maturation of the oocytes.
Brian L. Weiss - One of the best experts on this subject based on the ideXlab platform.
-
Two feeding-induced proteins from the male gonad trigger engorgement of the female tick Amblyomma hebraeum
Proceedings of the National Academy of Sciences of the United States of America, 2004Co-Authors: Brian L. Weiss, W. Reuben KaufmanAbstract:Most female ixodid ticks, once mated, feed to repletion within 6–10 days. Previous studies indicate that an engorgement factor (EF), passed to the female during copulation, may be the stimulus for engorgement. Here, we show that extracts of the testis/vas deferens of fed (but not unfed) male Amblyomma hebraeum contain EF bioactivity when injected into the hemocoel of feeding virgins. We have produced recombinant proteins (recproteins) from 28 feeding-induced genes in the male gonad and have identified a recombinant A. hebraeum engorgement factor (recAhEF) among these recproteins. recAhEF is a combination of two peptides, recAhEFα (16.1 kDa) and recAhEFβ (11.6 kDa), neither of which has bioactivity on its own. recAhEF also stimulates salivary gland degeneration and partial development of the ovary, suggesting that it may be the same material as another male gonadal protein from this tick, male factor. We propose the name “voraxin” for the natural EF of ticks. When normal mated females were put on a rabbit immunized against recAhEF, 74% failed to feed beyond one-tenth the normal engorged weight within 14 days whereas all mated ticks put on a control rabbit engorged normally (mean duration of 8.8 ± 0.8 days). This result constitutes preliminary evidence that an anti-tick vaccine might be developed from voraxin.
-
identification and characterization of genes differentially expressed in the testis vas deferens of the fed male tick Amblyomma hebraeum
Insect Biochemistry and Molecular Biology, 2002Co-Authors: Brian L. Weiss, Jadwiga M Stepczynski, Paul Wong, Reuben W. KaufmanAbstract:Most ixodid ticks must feed for at least a few days to complete gonad maturation. Substances produced by the mature male gonad, and carried in the spermatophore, induce physiological changes in the female that lead to engorgement and oviposition. To begin defining the molecular phenotype at this stage of male development, we differentially cross-screened a cDNA library made from the testis and vas deferens of fed ticks (Amblyomma hebraeum Koch) and isolated 35 genes that were putatively up-regulated in tissues of fed compared to unfed animals. While the majority of these were novel, two clones, AhT/VD16 and AhT/VD146, yielded homologies (53 and 44%) to known genes (acylphosphatse and 9.0 kD Drosophila melanogaster basic protein, respectively). Results of Northern blot analysis of AhT/VD16 and AhT/VD146 demonstrate that both clones hybridized with mRNA transcripts that were up-regulated in the testis/vas deferens of fed compared to unfed males. In addition, hybridization of clone AhT/VD16 to water strider (Gerris argentatus) genomic DNA, and sequence similarities to mammalian acylphosphatase, suggest that it represents an evolutionarily conserved sequence.
-
Identification and characterization of genes differentially expressed in the testis/vas deferens of the fed male tick, Amblyomma hebraeum
Insect biochemistry and molecular biology, 2002Co-Authors: Brian L. Weiss, Jadwiga M Stepczynski, Paul Wong, W. Reuben KaufmanAbstract:Most ixodid ticks must feed for at least a few days to complete gonad maturation. Substances produced by the mature male gonad, and carried in the spermatophore, induce physiological changes in the female that lead to engorgement and oviposition. To begin defining the molecular phenotype at this stage of male development, we differentially cross-screened a cDNA library made from the testis and vas deferens of fed ticks (Amblyomma hebraeum Koch) and isolated 35 genes that were putatively up-regulated in tissues of fed compared to unfed animals. While the majority of these were novel, two clones, AhT/VD16 and AhT/VD146, yielded homologies (53 and 44%) to known genes (acylphosphatse and 9.0 kD Drosophila melanogaster basic protein, respectively). Results of Northern blot analysis of AhT/VD16 and AhT/VD146 demonstrate that both clones hybridized with mRNA transcripts that were up-regulated in the testis/vas deferens of fed compared to unfed males. In addition, hybridization of clone AhT/VD16 to water strider (Gerris argentatus) genomic DNA, and sequence similarities to mammalian acylphosphatase, suggest that it represents an evolutionarily conserved sequence.
-
The relationship between 'critical weight' and 20-hydroxyecdysone in the female ixodid tick, Amblyomma hebraeum.
Journal of insect physiology, 2001Co-Authors: Brian L. Weiss, W. Reuben KaufmanAbstract:THE FEEDING CYCLE OF ADULT FEMALE TICKS (ACARI: Ixodidae) is divided into preparatory, slow and rapid feeding phases. At the transition from slow to rapid feeding, Amblyomma hebraeum (Koch) females reach a 'critical weight' (CW; approx. 10x the unfed weight) that is characterized by several behavioural and physiological changes. Five of these changes were used as criteria to establish a more precise estimate of CW than we have to date. The CW as defined by re-attachment to the host was 9x the unfed weight, while for haemolymph ecdysteroid titre, salivary gland degeneration, ovary weight, oocyte length and oocyte vitellin content the CW was 10x, 10x, 12x, 12x and 13x, respectively. CW thus varies depending on the parameter measured. Although previous studies have established the influence of ecdysteroids on salivary gland degeneration and vitellogenesis, here we demonstrate a further effect of ecdysteroids: inhibiting re-attachment to the host.
Estelle Hildegard Venter - One of the best experts on this subject based on the ideXlab platform.
-
evidence of transstadial and mechanical transmission of lumpy skin disease virus by Amblyomma hebraeum ticks
Transboundary and Emerging Diseases, 2015Co-Authors: Jimmy Clement Lubinga, Eeva S. M. Tuppurainen, W. H. Stoltsz, Jacobus A.w. Coetzer, R Mahlare, Estelle Hildegard VenterAbstract:Lumpy skin disease (LSD) is an economically important disease caused by LSD virus (LSDV), a Capripoxvirus, characterized by fever and circumscribed skin lesions. It is suspected to be transmitted mechanically by biting flies. To assess the vector potential of Amblyomma hebraeum in transmission of LSDV, mechanical/intrastadial and transstadial modes of transmission of the virus by this tick species were investigated. Two cattle were artificially infected as sources (donors) of infection to ticks. Ticks were infected as either nymphs or adults. Male A. hebraeum ticks were partially fed on donor animals and transferred to recipient animals to test for mechanical/intrastadial transmission. Nymphal A. hebraeum were fed to repletion on donor animals. The emergent adult ticks were placed on recipient animals to test for transstadial transmission of the virus. Successful transmission of LSDV infection was determined in recipient animals by monitoring development of clinical signs, testing of blood for the presence of LSDV by real-time PCR, virus isolation and the serum neutralization test. This report provides further evidence of mechanical/intrastadial and, for the first time, transstadial transmission of LSDV by A. hebraeum. These findings implicate A. hebraeum as a possible maintenance host in the epidemiology of the disease.
-
Demonstration of lumpy skin disease virus infection in Amblyomma hebraeum and Rhipicephalus appendiculatus ticks using immunohistochemistry.
Ticks and tick-borne diseases, 2013Co-Authors: Jimmy Clement Lubinga, Shawn Babiuk, Eeva S. M. Tuppurainen, W. H. Stoltsz, Jacobus A.w. Coetzer, Sarah J. Clift, Estelle Hildegard VenterAbstract:Lumpy skin disease (LSD) is caused by lumpy skin disease virus (LSDV), a member of the genus Capripoxvirus. Transmission of the virus has been associated with haematophagous insects such as Stomoxys calcitrans as well as Aedes and Culex species of mosquitoes. Recent studies have reported the transmission of the virus by Amblyomma hebraeum, Rhipicephalus appendiculatus, and Rhipicephalus decoloratus ticks and the presence of LSDV in saliva of A. hebraeum and R. appendiculatus ticks. The aim of this study was to determine which tick organs become infected by LSDV following intrastadial infection and transstadial persistence of the virus in A. hebraeum and R. appendiculatus ticks. Nymphal and adult ticks were orally infected by feeding them on LSDV-infected cattle. Partially fed adult ticks were processed for testing while nymphs were fed to repletion and allowed to moult to adults before being processed for testing. The infection in tick organs was determined by testing for the presence of the viral antigen using monoclonal antibodies with immunohistochemical staining. The viral antigen was detected in salivary glands, haemocytes, synganglia, ovaries, testes, fat bodies, and midgut. Since the virus was shown to be able to cross the midgut wall and infect various tick organs, this may indicate potential for biological development and transmission of LSDV in ticks. This study strengthens the previously reported evidence of the occurrence of LSDV in tick saliva.
-
Collection of free-living nymphs and adults of Amblyomma hebraeum (Acari: Ixodidae) with pheromone/carbon dioxide traps at 5 different ecological sites in heartwater endemic regions of South Africa.
Experimental & applied acarology, 2000Co-Authors: N.r. Bryson, Estelle Hildegard Venter, Ivan Gerard Horak, C. E. YunkerAbstract:The capture of free-living adults and nymphs of Amblyomma hebraeum, the main vector of heartwater in domestic and wild ruminants in South Africa, by means of attraction–aggregation–attachment–pheromone/carbon dioxide traps at five endemic localities in South Africa is described. Although the traps were used successfully at each of the localities, no determination of their efficiency in relation to the actual abundance of ticks at a particular site was made. This study confirmed that the traps could be used in a variety of ecological areas to locate populations of free-living adult A. hebraeum.
-
collection of free living nymphs and adults of Amblyomma hebraeum acari ixodidae with pheromone carbon dioxide traps at 5 different ecological sites in heartwater endemic regions of south africa
Experimental and Applied Acarology, 2000Co-Authors: N.r. Bryson, Estelle Hildegard Venter, Ivan Gerard Horak, C. E. YunkerAbstract:The capture of free-living adults and nymphs of Amblyomma hebraeum, the main vector of heartwater in domestic and wild ruminants in South Africa, by means of attraction–aggregation–attachment–pheromone/carbon dioxide traps at five endemic localities in South Africa is described. Although the traps were used successfully at each of the localities, no determination of their efficiency in relation to the actual abundance of ticks at a particular site was made. This study confirmed that the traps could be used in a variety of ecological areas to locate populations of free-living adult A. hebraeum.
Reuben W. Kaufman - One of the best experts on this subject based on the ideXlab platform.
-
© 2015. Published by The Company of Biologists Ltd Mechanical properties of the cuticle of the tick, Amblyomma hebraeum (Acari: Ixodidae)
2016Co-Authors: Peter C. Flynn, Reuben W. KaufmanAbstract:Summary Statement: Female Amblyomma hebraeum grow cuticle post moult prior to feeding; the cuticle stiffens. Mechanical analysis suggests that dopamine but not water content enables stretch and thinning of cuticle in the rapid phase of engorgement
-
quantification of vitellogenesis and its control by 20 hydroxyecdysone in the ixodid tick Amblyomma hebraeum
Journal of Insect Physiology, 2002Co-Authors: Kevin J. Friesen, Reuben W. KaufmanAbstract:Abstract Ovaries of the ixodid tick, Amblyomma hebraeum Koch, grew rapidly after engorgment as a result of yolk uptake. At 26 °C, oviposition began by day 10 post-engorgement, plateaued on days 16–18, and ended by day 38. Vitellin (Vt) was partially purified from ovaries of day 10 engorged ticks by gel filtration and ion exchange chromatography. This Vt comprises seven major and several minor polypeptides. Two polypeptides (211 and 148 kD) from haemolymph of engorged female ticks corresponded to minor polypeptides of similar molecular weight in the ovary. The haemolymph titre of the 211 and 148 kD polypeptides increased up to the onset of oviposition. These polypeptides were absent in males and non-vitellogenic females (day 0 engorged or day 10 partially-fed females), and were thus designated as vitellogenin (Vg). Antibodies raised against haemolymph Vg211 and 148 recognized these polypeptides in partially purified Vt, as well as six of the seven major polypeptides. Using these antibodies we developed an indirect, competitive ELISA to quantify Vg. Rise in haemolymph Vg-concentration lagged slightly behind the rise in haemolymph ecdysteroid (ES)-concentration, and Vg-synthesis was stimulated by injections of 20E into non-vitellogenic females. These observations indicate that an ES is the vitellogenic hormone in A. hebraeum .
-
identification and characterization of genes differentially expressed in the testis vas deferens of the fed male tick Amblyomma hebraeum
Insect Biochemistry and Molecular Biology, 2002Co-Authors: Brian L. Weiss, Jadwiga M Stepczynski, Paul Wong, Reuben W. KaufmanAbstract:Most ixodid ticks must feed for at least a few days to complete gonad maturation. Substances produced by the mature male gonad, and carried in the spermatophore, induce physiological changes in the female that lead to engorgement and oviposition. To begin defining the molecular phenotype at this stage of male development, we differentially cross-screened a cDNA library made from the testis and vas deferens of fed ticks (Amblyomma hebraeum Koch) and isolated 35 genes that were putatively up-regulated in tissues of fed compared to unfed animals. While the majority of these were novel, two clones, AhT/VD16 and AhT/VD146, yielded homologies (53 and 44%) to known genes (acylphosphatse and 9.0 kD Drosophila melanogaster basic protein, respectively). Results of Northern blot analysis of AhT/VD16 and AhT/VD146 demonstrate that both clones hybridized with mRNA transcripts that were up-regulated in the testis/vas deferens of fed compared to unfed males. In addition, hybridization of clone AhT/VD16 to water strider (Gerris argentatus) genomic DNA, and sequence similarities to mammalian acylphosphatase, suggest that it represents an evolutionarily conserved sequence.
Jimmy Clement Lubinga - One of the best experts on this subject based on the ideXlab platform.
-
evidence of transstadial and mechanical transmission of lumpy skin disease virus by Amblyomma hebraeum ticks
Transboundary and Emerging Diseases, 2015Co-Authors: Jimmy Clement Lubinga, Eeva S. M. Tuppurainen, W. H. Stoltsz, Jacobus A.w. Coetzer, R Mahlare, Estelle Hildegard VenterAbstract:Lumpy skin disease (LSD) is an economically important disease caused by LSD virus (LSDV), a Capripoxvirus, characterized by fever and circumscribed skin lesions. It is suspected to be transmitted mechanically by biting flies. To assess the vector potential of Amblyomma hebraeum in transmission of LSDV, mechanical/intrastadial and transstadial modes of transmission of the virus by this tick species were investigated. Two cattle were artificially infected as sources (donors) of infection to ticks. Ticks were infected as either nymphs or adults. Male A. hebraeum ticks were partially fed on donor animals and transferred to recipient animals to test for mechanical/intrastadial transmission. Nymphal A. hebraeum were fed to repletion on donor animals. The emergent adult ticks were placed on recipient animals to test for transstadial transmission of the virus. Successful transmission of LSDV infection was determined in recipient animals by monitoring development of clinical signs, testing of blood for the presence of LSDV by real-time PCR, virus isolation and the serum neutralization test. This report provides further evidence of mechanical/intrastadial and, for the first time, transstadial transmission of LSDV by A. hebraeum. These findings implicate A. hebraeum as a possible maintenance host in the epidemiology of the disease.
-
Transovarial passage and transmission of LSDV by Amblyomma hebraeum, Rhipicephalus appendiculatus and Rhipicephalus decoloratus
Experimental and Applied Acarology, 2014Co-Authors: Jimmy Clement Lubinga, Eeva S. M. Tuppurainen, W. H. Stoltsz, Jacobus A.w. Coetzer, Estelle H. VenterAbstract:Lumpy skin disease (LSD), an acute, sub-acute or inapparent disease of cattle, is caused by lumpy skin disease virus (LSDV), a member of the genus Capripoxvirus in the family Poxviridae. LSD is characterised by high fever, formation of circumscribed skin lesions and ulcerative lesions on the mucous membranes of the mouth, respiratory and digestive tracts. It is an economically important disease due to the permanent damage to hides, the reduction in productivity and trade restrictions imposed on affected areas. Transmission has been associated with blood-feeding insects such as stable flies ( Stomoxysis calcitrans ) and mosquitoes ( Aedes aegypti ). Mechanical (intrastadial) and transstadial transmission by Amblyomma hebraeum and Rhipicephalus appendiculatus as well as transovarial transmission by R. decoloratus have been reported. In this study transovarial passage of LSDV to larvae and subsequent transmission to recipient animals were demonstrated. The finding of transovarial passage of LSDV in female ticks shows the potential for A. hebraeum, R. appendiculatus and R. decoloratus to be reservoir hosts for LSDV.
-
Demonstration of lumpy skin disease virus infection in Amblyomma hebraeum and Rhipicephalus appendiculatus ticks using immunohistochemistry.
Ticks and tick-borne diseases, 2013Co-Authors: Jimmy Clement Lubinga, Shawn Babiuk, Eeva S. M. Tuppurainen, W. H. Stoltsz, Jacobus A.w. Coetzer, Sarah J. Clift, Estelle Hildegard VenterAbstract:Lumpy skin disease (LSD) is caused by lumpy skin disease virus (LSDV), a member of the genus Capripoxvirus. Transmission of the virus has been associated with haematophagous insects such as Stomoxys calcitrans as well as Aedes and Culex species of mosquitoes. Recent studies have reported the transmission of the virus by Amblyomma hebraeum, Rhipicephalus appendiculatus, and Rhipicephalus decoloratus ticks and the presence of LSDV in saliva of A. hebraeum and R. appendiculatus ticks. The aim of this study was to determine which tick organs become infected by LSDV following intrastadial infection and transstadial persistence of the virus in A. hebraeum and R. appendiculatus ticks. Nymphal and adult ticks were orally infected by feeding them on LSDV-infected cattle. Partially fed adult ticks were processed for testing while nymphs were fed to repletion and allowed to moult to adults before being processed for testing. The infection in tick organs was determined by testing for the presence of the viral antigen using monoclonal antibodies with immunohistochemical staining. The viral antigen was detected in salivary glands, haemocytes, synganglia, ovaries, testes, fat bodies, and midgut. Since the virus was shown to be able to cross the midgut wall and infect various tick organs, this may indicate potential for biological development and transmission of LSDV in ticks. This study strengthens the previously reported evidence of the occurrence of LSDV in tick saliva.