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Lane D Foil - One of the best experts on this subject based on the ideXlab platform.

  • tabanids neglected subjects of research but important vectors of disease agents
    Infection Genetics and Evolution, 2014
    Co-Authors: Frederic Baldacchino, Marc Desquesnes, Steve Mihok, Lane D Foil, Gerard Duvallet, Sathaporn Jittapalapong
    Abstract:

    Tabanids are nuisance pests for people and livestock because of their painful and irritating bite, persistent biting behavior, and blood ingestion. About 4400 tabanid species have been described; they are seasonally present in all kinds of landscapes, latitudes, and altitudes. High populations have a significant economic impact on outdoor activities, tourism, and livestock production. Tabanids are also vectors of animal disease agents, including viruses, bacteria and parasites. However, tabanids have received little attention in comparison with other hematophagous Diptera. Here, we highlight the many direct and indirect impacts of tabanids and provide a brief summary of tabanid morphology, biology, and life cycle. Impacts include pathogen Transmission, parasite transportation (Dermatobia hominis), biological Transmission (Loa loa), and Mechanical Transmission of viruses, such as equine infectious anemia virus, protozoa, such as Trypanosoma evansi and Besnotia besnoiti, and bacteria, such as Bacillus anthracis and Anaplasma marginale. We discuss parameters of Mechanical Transmission and its mathematical modeling. Control methods for tabanid populations are also summarized; these include trapping, the use of insecticides, repellents, and livestock protection. Lastly recommendations are provided for the direction of future research.

  • comparison of the efficiency of biological Transmission of anaplasma marginale rickettsiales anaplasmataceae by dermacentor andersoni stiles acari ixodidae with Mechanical Transmission by the horse fly tabanus fuscicostatus hine diptera muscidae
    Journal of Medical Entomology, 2008
    Co-Authors: Glen A Scoles, Allen J Miller, Lane D Foil
    Abstract:

    Mechanical Transmission of Anaplasma marginale by horse flies (Tabanidae) is thought to be epidemiologically significant in some areas of the United States. We compared the relative efficiencies of Mechanical Transmission of Anaplasma marginale by the horse fly, Tabanus fuscicostatus Hine, during acute infection (≈107 to ≈109 infected erythrocytes [IE]/ml blood) with biological Transmission by Dermacentor andersoni Stiles in the persistent phase of infection (≈102.5 to ≈106 IE/ml). Transmission of A. marginale was not observed when horse flies were partially fed on an acutely infected donor calf and immediately transferred to susceptible calves to complete their blood meal. Ticks that were acquisition fed on the same donor host after it reached the persistent phase of infection successfully transmitted A. marginale when transferred to the same recipient calves that failed to acquire infection after fly feeding. Failure of fly-borne Mechanical Transmission at a rickettsemia >240-fold higher than that from which ticks transmitted with 100% efficiency shows that tick-borne biological Transmission is at least two orders of magnitude more efficient than Mechanical Transmission by horse flies.

  • comparison of the efficiency of biological Transmission of anaplasma marginale rickettsiales anaplasmataceae by dermacentor andersoni stiles acari ixodidae with Mechanical Transmission by the horse fly tabanus fuscicostatus hine diptera muscidae erra
    Journal of Medical Entomology, 2008
    Co-Authors: Glen A Scoles, J A Miller, Lane D Foil
    Abstract:

    Mechanical Transmission of Anaplasma marginale by horse flies (Tabanidae) is thought to be epidemiologically significant in some areas of the United States. We compared the relative efficiencies of Mechanical Transmission of Anaplasma marginale by the horse fly, Tabanus fuscicostatus Hine, during acute infection (approximately equal to10⁷ to approximately equal to 10⁹ infected erythrocytes [IE]/ml blood) with biological Transmission by Dermacentor andersoni Stiles in the persistent phase of infection (approximately equal to 10(2.5) to approximately equal to 10⁶ IE/ml). Transmission of A. marginale was not observed when horse flies were partially fed on an acutely infected donor calf and immediately transferred to susceptible calves to complete their blood meal. Ticks that were acquisition fed on the same donor host after it reached the persistent phase of infection successfully transmitted A. marginale when transferred to the same recipient calves that failed to acquire infection after fly feeding. Failure of fly-borne Mechanical Transmission at a rickettsemia >240-fold higher than that from which ticks transmitted with 100% efficiency shows that tick-borne biological Transmission is at least two orders of magnitude more efficient than Mechanical Transmission by horse flies.

  • the influence of distance on movement of tabanids diptera tabanidae between horses
    Veterinary Parasitology, 2007
    Co-Authors: Antonio Thadeu Medeiros De Barros, Lane D Foil
    Abstract:

    Two studies evaluated the potential use of spatial barriers to reduce the Mechanical Transmission of disease agents by tabanids in the Pantanal region of Brazil. Tabanids at stations separated by four different distances (5, 10, 25, and 50 m) were marked. In the first study, tabanids were marked and allowed to feed until engorgement or natural interruption occurred and captured if they transferred to the other horse. A total of 2847 tabanids belonging to nine different species were marked. The percentage of tabanids that moved between horses was 10.5 at 5 m, 6.8 at 10 m, and 4.6 at 25 m. In the second study, flies were marked, feeding was then interrupted, and the flies were released approximately 50 cm from the host. A total of 1274 tabanids belonging to five different species were marked. The percentage of flies that moved between horses was 9.7 at 5 m, 9.7 at 10 m, and 4.6 at 25 m. No tabanids transferred between animals separated by 50 m in either experiment. The results of this study strongly support the recommendation that segregation of animals effectively prevents the Mechanical Transmission of pathogens by tabanids.

Glen A Scoles - One of the best experts on this subject based on the ideXlab platform.

  • comparison of the efficiency of biological Transmission of anaplasma marginale rickettsiales anaplasmataceae by dermacentor andersoni stiles acari ixodidae with Mechanical Transmission by the horse fly tabanus fuscicostatus hine diptera muscidae erra
    Journal of Medical Entomology, 2008
    Co-Authors: Glen A Scoles, J A Miller, Lane D Foil
    Abstract:

    Mechanical Transmission of Anaplasma marginale by horse flies (Tabanidae) is thought to be epidemiologically significant in some areas of the United States. We compared the relative efficiencies of Mechanical Transmission of Anaplasma marginale by the horse fly, Tabanus fuscicostatus Hine, during acute infection (approximately equal to10⁷ to approximately equal to 10⁹ infected erythrocytes [IE]/ml blood) with biological Transmission by Dermacentor andersoni Stiles in the persistent phase of infection (approximately equal to 10(2.5) to approximately equal to 10⁶ IE/ml). Transmission of A. marginale was not observed when horse flies were partially fed on an acutely infected donor calf and immediately transferred to susceptible calves to complete their blood meal. Ticks that were acquisition fed on the same donor host after it reached the persistent phase of infection successfully transmitted A. marginale when transferred to the same recipient calves that failed to acquire infection after fly feeding. Failure of fly-borne Mechanical Transmission at a rickettsemia >240-fold higher than that from which ticks transmitted with 100% efficiency shows that tick-borne biological Transmission is at least two orders of magnitude more efficient than Mechanical Transmission by horse flies.

  • comparison of the efficiency of biological Transmission of anaplasma marginale rickettsiales anaplasmataceae by dermacentor andersoni stiles acari ixodidae with Mechanical Transmission by the horse fly tabanus fuscicostatus hine diptera muscidae
    Journal of Medical Entomology, 2008
    Co-Authors: Glen A Scoles, Allen J Miller, Lane D Foil
    Abstract:

    Mechanical Transmission of Anaplasma marginale by horse flies (Tabanidae) is thought to be epidemiologically significant in some areas of the United States. We compared the relative efficiencies of Mechanical Transmission of Anaplasma marginale by the horse fly, Tabanus fuscicostatus Hine, during acute infection (≈107 to ≈109 infected erythrocytes [IE]/ml blood) with biological Transmission by Dermacentor andersoni Stiles in the persistent phase of infection (≈102.5 to ≈106 IE/ml). Transmission of A. marginale was not observed when horse flies were partially fed on an acutely infected donor calf and immediately transferred to susceptible calves to complete their blood meal. Ticks that were acquisition fed on the same donor host after it reached the persistent phase of infection successfully transmitted A. marginale when transferred to the same recipient calves that failed to acquire infection after fly feeding. Failure of fly-borne Mechanical Transmission at a rickettsemia >240-fold higher than that from which ticks transmitted with 100% efficiency shows that tick-borne biological Transmission is at least two orders of magnitude more efficient than Mechanical Transmission by horse flies.

  • relative efficiency of biological Transmission of anaplasma marginale rickettsiales anaplasmataceae by dermacentor andersoni acari ixodidae compared with Mechanical Transmission by stomoxys calcitrans diptera muscidae
    Journal of Medical Entomology, 2005
    Co-Authors: Glen A Scoles, Alberto B Broce, Timothy J. Lysyk, Guy H. Palmer
    Abstract:

    Abstract Anaplasma marginale Theiler is a tick-borne intraerythrocytic rickettsial pathogen of cattle that also can be Mechanically transmitted by biting flies. Rickettsemia during the acute phase of infection may reach as high as 109 infected erythrocytes (IEs) per milliliter of blood. Animals that survive acute infection develop a life-long persistent infection that cycles between 102.5 and 107 IE/ml of blood. We compared stable fly Stomoxys calcitrans (L.)-borne Mechanical Transmission during acute infection with Rocky Mountain wood tick, Dermacentor andersoni Stiles-borne biological Transmission in the persistent phase of infection to demonstrate quantitatively that biological Transmission by ticks is considerably more efficient than Mechanical Transmission by biting flies. Stable flies that partially fed on an acutely infected calf and were immediately transferred to susceptible calves to complete their bloodmeals failed to transmit A. marginale. Ticks that fed on the original acquisition host after ...

  • relative efficiency of biological Transmission of anaplasma marginale rickettsiales anaplasmataceae by dermacentor andersoni acari ixodidae compared with Mechanical Transmission by stomoxys calcitrans diptera muscidae
    Journal of Medical Entomology, 2005
    Co-Authors: Glen A Scoles, Alberto B Broce, Timothy J. Lysyk, Guy H. Palmer
    Abstract:

    Anaplasma marginale Theiler is a tick-borne intraerythrocytic rickettsial pathogen of cattle that also can be Mechanically transmitted by biting flies. Rickettsemia during the acute phase of infection may reach as high as 10(9) infected erythrocytes (IEs) per milliliter of blood. Animals that survive acute infection develop a life-long persistent infection that cycles between 10(2.5) and 10(7) IE/ ml of blood. We compared stable fly Stomoxys calcitrans (L.) -borne Mechanical Transmission during acute infection with Rocky Mountain wood tick, Dermacentor andersoni Stiles-borne biological Transmission in the persistent phase of infection to demonstrate quantitatively that biological Transmission by ticks is considerably more efficient than Mechanical Transmission by biting flies. Stable flies that partially fed on an acutely infected calf and were immediately transferred to susceptible calves to complete their bloodmeals failed to transmit A. marginale. Ticks that fed on the original acquisition host after it reached the persistent phase of infection (>300-fold lower rickettsemia) successfully transmitted A. marginale after transfer to the same calves that failed to acquire infection after fly feeding. Failure of fly-borne Mechanical Transmission at a rickettsemia >300-fold higher than that from which ticks transmit with 100% efficiency demonstrates that tick-borne biological Transmission is at least 2 orders of magnitude more efficient than direct stable fly-borne Mechanical Transmission.

Guy H. Palmer - One of the best experts on this subject based on the ideXlab platform.

  • relative efficiency of biological Transmission of anaplasma marginale rickettsiales anaplasmataceae by dermacentor andersoni acari ixodidae compared with Mechanical Transmission by stomoxys calcitrans diptera muscidae
    Journal of Medical Entomology, 2005
    Co-Authors: Glen A Scoles, Alberto B Broce, Timothy J. Lysyk, Guy H. Palmer
    Abstract:

    Abstract Anaplasma marginale Theiler is a tick-borne intraerythrocytic rickettsial pathogen of cattle that also can be Mechanically transmitted by biting flies. Rickettsemia during the acute phase of infection may reach as high as 109 infected erythrocytes (IEs) per milliliter of blood. Animals that survive acute infection develop a life-long persistent infection that cycles between 102.5 and 107 IE/ml of blood. We compared stable fly Stomoxys calcitrans (L.)-borne Mechanical Transmission during acute infection with Rocky Mountain wood tick, Dermacentor andersoni Stiles-borne biological Transmission in the persistent phase of infection to demonstrate quantitatively that biological Transmission by ticks is considerably more efficient than Mechanical Transmission by biting flies. Stable flies that partially fed on an acutely infected calf and were immediately transferred to susceptible calves to complete their bloodmeals failed to transmit A. marginale. Ticks that fed on the original acquisition host after ...

  • relative efficiency of biological Transmission of anaplasma marginale rickettsiales anaplasmataceae by dermacentor andersoni acari ixodidae compared with Mechanical Transmission by stomoxys calcitrans diptera muscidae
    Journal of Medical Entomology, 2005
    Co-Authors: Glen A Scoles, Alberto B Broce, Timothy J. Lysyk, Guy H. Palmer
    Abstract:

    Anaplasma marginale Theiler is a tick-borne intraerythrocytic rickettsial pathogen of cattle that also can be Mechanically transmitted by biting flies. Rickettsemia during the acute phase of infection may reach as high as 10(9) infected erythrocytes (IEs) per milliliter of blood. Animals that survive acute infection develop a life-long persistent infection that cycles between 10(2.5) and 10(7) IE/ ml of blood. We compared stable fly Stomoxys calcitrans (L.) -borne Mechanical Transmission during acute infection with Rocky Mountain wood tick, Dermacentor andersoni Stiles-borne biological Transmission in the persistent phase of infection to demonstrate quantitatively that biological Transmission by ticks is considerably more efficient than Mechanical Transmission by biting flies. Stable flies that partially fed on an acutely infected calf and were immediately transferred to susceptible calves to complete their bloodmeals failed to transmit A. marginale. Ticks that fed on the original acquisition host after it reached the persistent phase of infection (>300-fold lower rickettsemia) successfully transmitted A. marginale after transfer to the same calves that failed to acquire infection after fly feeding. Failure of fly-borne Mechanical Transmission at a rickettsemia >300-fold higher than that from which ticks transmit with 100% efficiency demonstrates that tick-borne biological Transmission is at least 2 orders of magnitude more efficient than direct stable fly-borne Mechanical Transmission.

Kaishu Ling - One of the best experts on this subject based on the ideXlab platform.

  • evaluation of disinfectants to prevent Mechanical Transmission of viruses and a viroid in greenhouse tomato production
    Virology Journal, 2015
    Co-Authors: Rugang Li, F Baysalgurel, Zaid Abdo, Sally A Miller, Kaishu Ling
    Abstract:

    Background In recent years, a number of serious disease outbreaks caused by viruses and viroids on greenhouse tomatoes in North America have resulted in significant economic losses to growers. The objectives of this study were to evaluate the effectiveness of commercial disinfectants against Mechanical Transmission of these pathogens, and to select disinfectants with broad spectrum reactivity to control general virus and viroid diseases in greenhouse tomato production.

  • pepino mosaic virus on tomato seed virus location and Mechanical Transmission
    Plant Disease, 2008
    Co-Authors: Kaishu Ling
    Abstract:

    ABSTRACT In just a few years, Pepino mosaic virus (PepMV) has become a major threat to greenhouse tomato production around the world. Although tomato seed is suspected to spread the disease, its importance as an initial virus inoculum for PepMV has not been established. To determine the potential for seed Transmission, a tomato seed lot highly contaminated with PepMV was used for large-scale seedling grow-out tests. None of 10,000 grow-out seedlings was infected as determined by symptom expression, enzyme-linked immunosorbent assay (ELISA), or infectivity assay on Nicotiana benthamiana. Even though PepMV was not seed transmitted on tomato, the virus was effectively transmitted to tomato and N. benthamiana seedlings through Mechanical Transmission with seed extract. To examine the exact location where PepMV particles accumulated on the tomato seed, seed coats and embryos were carefully isolated and tested separately by ELISA, real-time RT-PCR, and bioassay on N. benthamiana. PepMV was detected in the seed ...

  • pepino mosaic virus on tomato seed virus location and Mechanical Transmission
    Plant Disease, 2008
    Co-Authors: Kaishu Ling
    Abstract:

    In just a few years, Pepino mosaic virus (PepMV) has become a major threat to greenhouse tomato production around the world. Although tomato seed is suspected to spread the disease, its importance as an initial virus inoculum for PepMV has not been established. To determine the potential for seed Transmission, a tomato seed lot highly contaminated with PepMV was used for large-scale seedling grow-out tests. None of 10,000 grow-out seedlings was infected as determined by symptom expression, enzyme-linked immunosorbent assay (ELISA), or infectivity assay on Nicotiana benthamiana. Even though PepMV was not seed transmitted on tomato, the virus was effectively transmitted to tomato and N. benthamiana seedlings through Mechanical Transmission with seed extract. To examine the exact location where PepMV particles accumulated on the tomato seed, seed coats and embryos were carefully isolated and tested separately by ELISA, real-time RT-PCR, and bioassay on N. benthamiana. PepMV was detected in the seed coat fraction in both immature and mature tomato seeds, but not in the embryo. However, in N. benthamiana, the virus was neither seedborne nor seed-transmitted. Because PepMV is seedborne in tomato, efficient Mechanical Transmission of PepMV from the virus-contaminated tomato seed to seedlings could initiate a disease epidemic in a new tomato growing area. Thus, it is important to plant certified tomato seed that has been tested free of PepMV.

Marc Desquesnes - One of the best experts on this subject based on the ideXlab platform.

  • Mechanical Transmission of african swine fever virus by stomoxys calcitrans insights from a mechanistic model
    Transboundary and Emerging Diseases, 2020
    Co-Authors: Timothée Vergne, Mathieu Andraud, Sarah Bonnet, Nick De Regge, Marc Desquesnes, Johanna Fite, Florence Etore, Mutien‐marie Garigliany, Ferran Jori, Laetitia Lempereur
    Abstract:

    African swine fever (ASF) represents a global threat with huge economic consequences for the swine industry. Even though direct contact is likely to be the main Transmission route from infected to susceptible hosts, recent epidemiological investigations have raised questions regarding the role of haematophagous arthropods, in particular the stable fly (Stomoxys calcitrans). In this study, we developed a mechanistic vector-borne Transmission model for ASF virus (ASFV) within an outdoor domestic pig farm in order to assess the relative contribution of stable flies to the spread of the virus. The model was fitted to the ecology of the vector, its blood-feeding behaviour and pig-to-pig Transmission dynamic. Model outputs suggested that in a context of low abundance (<5 flies per pig), stable flies would play a minor role in the spread of ASFV, as they are expected to be responsible for around 10% of Transmission events. However, with abundances of 20 and 50 stable flies per pig, the vector-borne Transmission would likely be responsible for almost 30% and 50% of Transmission events, respectively. In these situations, time to reach a pig mortality of 10% would be reduced by around 26% and 40%, respectively. The sensitivity analysis emphasized that the expected relative contribution of stable flies was strongly dependent on the volume of blood they regurgitated and the infectious dose for pigs. This study identified crucial knowledge gaps that need to be filled in order to assess more precisely the potential contribution of stable flies to the spread of ASFV, including a quantitative description of the populations of haematophagous arthropods that could be found in pig farms, a better understanding of blood-feeding behaviours of stable flies and the quantification of the probability that stable flies partially fed with infectious blood transmit the virus to a susceptible pig during a subsequent blood-feeding attempt.

  • Mechanical Transmission of African swine fever virus by Stomoxys calcitrans : Insights from a mechanistic model
    Transboundary and emerging diseases, 2020
    Co-Authors: Timothée Vergne, Mathieu Andraud, Sarah Bonnet, Nick De Regge, Marc Desquesnes, Johanna Fite, Florence Etore, Mutien‐marie Garigliany, Ferran Jori, Laetitia Lempereur
    Abstract:

    African swine fever (ASF) represents a global threat with huge economic consequences for the swine industry. Even though direct contact is likely to be the main Transmission route from infected to susceptible hosts, recent epidemiological investigations have raised questions regarding the role of haematophagous arthropods, in particular the stable fly (Stomoxys calcitrans). In this study, we developed a mechanistic vector-borne Transmission model for ASF virus (ASFV) within an outdoor domestic pig farm in order to assess the relative contribution of stable flies to the spread of the virus. The model was fitted to the ecology of the vector, its blood-feeding behaviour and pig-to-pig Transmission dynamic. Model outputs suggested that in a context of low abundance (

  • tabanids neglected subjects of research but important vectors of disease agents
    Infection Genetics and Evolution, 2014
    Co-Authors: Frederic Baldacchino, Marc Desquesnes, Steve Mihok, Lane D Foil, Gerard Duvallet, Sathaporn Jittapalapong
    Abstract:

    Tabanids are nuisance pests for people and livestock because of their painful and irritating bite, persistent biting behavior, and blood ingestion. About 4400 tabanid species have been described; they are seasonally present in all kinds of landscapes, latitudes, and altitudes. High populations have a significant economic impact on outdoor activities, tourism, and livestock production. Tabanids are also vectors of animal disease agents, including viruses, bacteria and parasites. However, tabanids have received little attention in comparison with other hematophagous Diptera. Here, we highlight the many direct and indirect impacts of tabanids and provide a brief summary of tabanid morphology, biology, and life cycle. Impacts include pathogen Transmission, parasite transportation (Dermatobia hominis), biological Transmission (Loa loa), and Mechanical Transmission of viruses, such as equine infectious anemia virus, protozoa, such as Trypanosoma evansi and Besnotia besnoiti, and bacteria, such as Bacillus anthracis and Anaplasma marginale. We discuss parameters of Mechanical Transmission and its mathematical modeling. Control methods for tabanid populations are also summarized; these include trapping, the use of insecticides, repellents, and livestock protection. Lastly recommendations are provided for the direction of future research.

  • Mechanical Transmission of trypanosoma vivax in cattle by the african tabanid atylotus fuscipes
    Veterinary Parasitology, 2004
    Co-Authors: Marc Desquesnes, Mamadou Lamine Dia
    Abstract:

    An experiment was carried out in Burkina Faso to evaluate the potential for Mechanical Transmission of Trypanosoma vivax by the African tabanid Atylotus fuscipes. The experiment was carried out in a corral (10 m x 10 m) completely covered by a mosquito net (12 m x 12 m and 2.5m high). Eight heifers (cross-bred Zebu X Baoule), free of trypanosome infection, were kept together with two heifers experimentally infected with a local stock of T. vivax. An average of 539 A. fuscipes per day, freshly captured with two Nzi traps, were introduced into the mosquito net from Day 1 to 20, to allow Mechanical Transmission of the parasites among cattle. Daily parasitological examinations (BCM) of cattle blood samples indicated that six of the eight receiver heifers were positive from days 9, 10, 15, 16, 19 and 29. Mechanical Transmission of T. vivax by A. fuscipes was demonstrated unequivocally in close to natural conditions, at a high rate (75% incidence over a 20-day period) under a mean challenge of 54 insects per heifer per day. These results, in addition to previous demonstration of Mechanical Transmission of T. vivax by Atylotus agrestis, confirm that Mechanical Transmission can be a significant route of infection.

  • Mechanical Transmission of trypanosoma congolense in cattle by the african tabanid atylotus agrestis
    Experimental Parasitology, 2003
    Co-Authors: Marc Desquesnes, Mamadou Lamine Dia
    Abstract:

    The trypanosomes pathogenic to livestock in Africa (Trypanosoma congolense, Trypanosoma vivax, and Trypanosoma brucei) are mainly cyclically transmitted by tsetse (Glossina). However, T. vivax, can also be Mechanically transmitted by haematophagous insects. Laboratory studies have demonstrated the Mechanical Transmission of T. congolense, but confirmation of this under natural conditions was necessary. An experiment was therefore carried out in Lahirasso, Burkina Faso, in a corral completely covered by mosquito net, to avoid exposure to tsetse. Eight receiver heifers, free of trypanosome infection, were kept together with two donor heifers, experimentally infected with local stocks of T. congolense. On average, 291 Atylotus agrestis, freshly captured in Nzi traps, were introduced into the mosquito net daily for a period of 20 days to initiate Mechanical Transmission among cattle. Daily microscopical observation of their blood indicated that two of the eight receiver heifers became infected with T. congolense from days 42 and 53. Mechanical Transmission of T. congolense by A. agrestis was demonstrated unequivocally with a 25% incidence over a 20-day period of exposure under a mean challenge of 29 insects/animal/day. These results, in addition to previous reports, demonstrate the ability of A. agrestis to transmit T. vivax and T. congolense to cattle in Africa by Mechanical means. Efforts to eliminate cattle trypanosomosis should therefore consider the eventual persistence of disease as a result of Mechanical Transmission of trypanosomes by tabanids. Index descriptor and abbreviations: Trypanosoma congolense (Trypanosomatidae) is a pathogenic trypanosome found in wild and domestic herbivores, principally in cattle (Bos taurus, Bos indicus, and cross-breds), in Africa. It is cyclically transmitted by tsetse (Glossina, Diptera); however, Mechanical Transmission by biting insects may also occur. The present study demonstrates unequivocally the Mechanical Transmission of T. congolense to cattle by one of the most common African tabanids, A. agrestis. The main conclusion is that tabanids are able to transmit T. congolense; however, the incidence of Transmission was lower than in studies carried out under the same conditions with T. vivax. Better models of Mechanical Transmission are required to understand why, on the one hand, epidemiological studies support the Mechanical Transmission of T. vivax but not T. congolense, and, on the other hand, experimental studies confirm that both species can be Mechanically transmitted. Our studies suggest that the epidemiology of trypanosomosis in cattle involves tabanids, and hence, the eradication of tsetse-flies in Africa will not necessarily lead to the eradication of trypanosomosis in domestic livestock. ADT, apparent density of insects per trap per day (mean number of insects caught in one type of trap per 24h of trapping); D, day; NS, not statistically significant