Refinar búsqueda
Resultados 391-400 de 824
Using genetic and phenetic markers to assess population isolation within the southernmost tsetse fly belt in Africa Texto completo
2019
Chantel J. De Beer | Gert J. Venter | Marc J.B. Vreysen | Fernando C. Mulandane | Luis Neves | Sihle Mdluli | Otto Koekemoer
Using genetic and phenetic markers to assess population isolation within the southernmost tsetse fly belt in Africa Texto completo
2019
Chantel J. De Beer | Gert J. Venter | Marc J.B. Vreysen | Fernando C. Mulandane | Luis Neves | Sihle Mdluli | Otto Koekemoer
The effective control of tsetse flies (Diptera; Glossinidae), the biological vectors of trypanosome parasites that cause human African trypanosomosis and African animal trypanosomosis throughout sub-Saharan Africa, is crucial for the development of productive livestock systems. The degree of genetic isolation of the targeted populations, which indicate reinvasion potential from uncontrolled areas, will be critical to establish a control strategy. Molecular and morphometrics markers were used to assess the degree of genetic isolation between seemingly fragmented populations of Glossina brevipalpis Newstead and Glossina austeni Newstead present in South Africa. These populations were also compared with flies from adjacent areas in Mozambique and Eswatini. For the molecular markers, deoxyribonucleic acid was extracted, a r16S2 Polymerase chain reaction (PCR) was performed and the PCR product sequenced. Nine landmarks were used for the morphometrics study as defined by vein intersections in the right wings of female flies. Generalised Procrustes analyses and regression on centroid size were used to determine the Cartesian coordinates for comparison between populations. Both methods indicated an absence of significant barriers to gene flow between the G. brevipalpis and G. austeni populations of South Africa and southern Mozambique. Sustainable control can only be achieved if implemented following an area-wide management approach against the entire G. brevipalpis and G. austeni populations of South Africa and southern Mozambique. Limited gene flow detected between the G. austeni population from Eswatini and that of South Africa or Mozambique may imply that these two populations are in the proses of becoming isolated.
Mostrar más [+] Menos [-]Using genetic and phenetic markers to assess population isolation within the southernmost tsetse fly belt in Africa Texto completo
2019
De Beer, Chantel J. | Venter, Gert J. | Vreysen, Marc J.B. | Mulandane, Fernando C. | Neves, Luis | Mdluli, Sihle | Koekemoer, Otto | The Department of Science and Technology South Africa | Department of Technical Cooperation of the IAEA
The effective control of tsetse flies (Diptera; Glossinidae), the biological vectors of trypanosome parasites that cause human African trypanosomosis and African animal trypanosomosis throughout sub-Saharan Africa, is crucial for the development of productive livestock systems. The degree of genetic isolation of the targeted populations, which indicate reinvasion potential from uncontrolled areas, will be critical to establish a control strategy. Molecular and morphometrics markers were used to assess the degree of genetic isolation between seemingly fragmented populations of Glossina brevipalpis Newstead and Glossina austeni Newstead present in South Africa. These populations were also compared with flies from adjacent areas in Mozambique and Eswatini. For the molecular markers, deoxyribonucleic acid was extracted, a r16S2 Polymerase chain reaction (PCR) was performed and the PCR product sequenced. Nine landmarks were used for the morphometrics study as defined by vein intersections in the right wings of female flies. Generalised Procrustes analyses and regression on centroid size were used to determine the Cartesian coordinates for comparison between populations. Both methods indicated an absence of significant barriers to gene flow between the G. brevipalpis and G. austeni populations of South Africa and southern Mozambique. Sustainable control can only be achieved if implemented following an area-wide management approach against the entire G. brevipalpis and G. austeni populations of South Africa and southern Mozambique. Limited gene flow detected between the G. austeni population from Eswatini and that of South Africa or Mozambique may imply that these two populations are in the proses of becoming isolated.
Mostrar más [+] Menos [-]Detection of native interferon-γ in nyala (Tragelaphus angasii): Towards diagnosing tuberculosis Texto completo
2019
Lezaan Roux | Alicia J. McCall | Anita L. Michel
Detection of native interferon-γ in nyala (Tragelaphus angasii): Towards diagnosing tuberculosis Texto completo
2019
Lezaan Roux | Alicia J. McCall | Anita L. Michel
Mycobacterium bovis is the main cause of tuberculosis in wildlife. In South Africa, African buffaloes (Syncerus caffer) are a wildlife maintenance host while a number of other species are considered spillover hosts. Nyala (Tragelaphus angasii), a large antelope species from Southern Africa, is frequently traded and can be infected with M. bovis. Interferon gamma (IFN-γ) release assays that detect cell-mediated immune (CMI) responses to M. bovis infection have shown promise in elephants, rhinoceroses and buffaloes. The BOVIGAM® assay is a commercial IFN-γ release assay designed to detect tuberculosis in cattle and has been validated in buffaloes. We tested the suitability of the BOVIGAM® assay to detect native IFN-γ release in nyala. Blood samples collected from 17 nyalas were stimulated with different mitogens and IFN-γ release measured. We found that incubating whole blood with phorbol 12-myristate 13-acetate and calcium ionophore (PMA/CaI) resulted in the highest levels of IFN-y release. Samples stimulated with tuberculin purified protein derivatives of M. bovis (PPDb) and M. avium (PPDa) did not show significant IFN-γ production. An intradermal tuberculin test (IDT) and culture of tissues from 15 of the 17 culled nyala were also performed, which supported the findings of the BOVIGAM® assay, suggesting the potential value of this assay for the diagnosis of tuberculosis in nyala.
Mostrar más [+] Menos [-]Detection of native interferon-γ in nyala (Tragelaphus angasii): Towards diagnosing tuberculosis Texto completo
2019
Roux, Lezaan | McCall, Alicia J. | Michel, Anita L. | National Research Foundation
Mycobacterium bovis is the main cause of tuberculosis in wildlife. In South Africa, African buffaloes (Syncerus caffer) are a wildlife maintenance host while a number of other species are considered spillover hosts. Nyala (Tragelaphus angasii), a large antelope species from Southern Africa, is frequently traded and can be infected with M. bovis. Interferon gamma (IFN-γ) release assays that detect cell-mediated immune (CMI) responses to M. bovis infection have shown promise in elephants, rhinoceroses and buffaloes. The BOVIGAM® assay is a commercial IFN-γ release assay designed to detect tuberculosis in cattle and has been validated in buffaloes. We tested the suitability of the BOVIGAM® assay to detect native IFN-γ release in nyala. Blood samples collected from 17 nyalas were stimulated with different mitogens and IFN-γ release measured. We found that incubating whole blood with phorbol 12-myristate 13-acetate and calcium ionophore (PMA/CaI) resulted in the highest levels of IFN-y release. Samples stimulated with tuberculin purified protein derivatives of M. bovis (PPDb) and M. avium (PPDa) did not show significant IFN-γ production. An intradermal tuberculin test (IDT) and culture of tissues from 15 of the 17 culled nyala were also performed, which supported the findings of the BOVIGAM® assay, suggesting the potential value of this assay for the diagnosis of tuberculosis in nyala.
Mostrar más [+] Menos [-]The haematological, proinflammatory cytokines and IgG changes during an ovine experimental theileriosis Texto completo
2019
Gholamreza Razmi | Saeed Yaghfoori | Mehrdad Mohri | Alirez Haghparast | Shahin Tajeri
The haematological, proinflammatory cytokines and IgG changes during an ovine experimental theileriosis Texto completo
2019
Gholamreza Razmi | Saeed Yaghfoori | Mehrdad Mohri | Alirez Haghparast | Shahin Tajeri
Malignant ovine theileriosis is caused by Theileria lestoquardi, which is highly pathogenic in sheep. Theileriosis involves different organs in ruminants. Little is known about the role of proinflammatory cytokines in the pathogenesis of T. lestoquardi infection. The aim of this study was to measure concentration changes of proinflammatory cytokines and immunoglobulin G (IgG) during an ovine experimental theileriosis and correlate it with clinical and haematological parameters. During an experimental study, seven healthy Baluchi sheep (four females and three males) about 6–8 months old were infected with T. lestoquardi by feeding of infected unfed ticks on the sheep’s ears. The infected sheep were clinically examined during the study and blood samples were collected on days 0, 2, 5, 7, 10, 12, 14, 17 and 21. The haematological parameters were analysed by an automatic veterinary haematology cell counter and the inflammatory cytokines interleukin-6 (IL-6), tumour necrosis factor-α (TNF-α), interferon-γ (IFN-γ) and IgG were measured by enzyme-linked immunosorbent assay. All infected sheep had temperatures above 40 °C on days 3–4 post infection (PI). The maximum temperature was noted on day 7, and it remained high until day 21. The parasitaemia of T. lestoquardi infection increased from 0.01% (day 7 PI) to 3.3% (day 21 PI). The mean white blood cell (WBC), red blood cell (RBC), lymphocyte, neutrophil and platelet values slightly increased on day 2 PI and decreased by day 17 and day 21 PI. The percentage parasitaemia and fever had a negative correlation with the numbers of WBCs, RBCs, lymphocytes, neutrophils and platelets. The serum concentration of IL-6, TNF-α and IFN-γ cytokines increased and peaked on day 12 and thereafter decreased to levels lower than 0. Out of all tested cytokines, the concentration of IL-6 was significantly higher, as early as day 2 PI. No significant changes were observed for the IgG levels during the course of disease. A significant and strong correlation was observed between IL-6, TNF-α and IFN-γ values and a moderate correlation between IL-6 and the numbers of lymphocytes in the present study. A strong correlation was determined between the percentage parasitaemia and haematological parameters in T. lestoquardi-infected sheep. In addition, preliminary results indicate that the measurement of the serum concentrations of IL-6 in combination with haematological parameters could be considered a good marker to estimate the pathogenicity of T. lestoquardi strain.
Mostrar más [+] Menos [-]The haematological, proinflammatory cytokines and IgG changes during an ovine experimental theileriosis Texto completo
2019
Razmi, Gholamreza | Yaghfoori, Saeed | Mohri, Mehrdad | Haghparast, Alirez | Tajeri, Shahin
Malignant ovine theileriosis is caused by Theileria lestoquardi, which is highly pathogenic in sheep. Theileriosis involves different organs in ruminants. Little is known about the role of proinflammatory cytokines in the pathogenesis of T. lestoquardi infection. The aim of this study was to measure concentration changes of proinflammatory cytokines and immunoglobulin G (IgG) during an ovine experimental theileriosis and correlate it with clinical and haematological parameters. During an experimental study, seven healthy Baluchi sheep (four females and three males) about 6–8 months old were infected with T. lestoquardi by feeding of infected unfed ticks on the sheep’s ears. The infected sheep were clinically examined during the study and blood samples were collected on days 0, 2, 5, 7, 10, 12, 14, 17 and 21. The haematological parameters were analysed by an automatic veterinary haematology cell counter and the inflammatory cytokines interleukin-6 (IL-6), tumour necrosis factor-α (TNF-α), interferon-γ (IFN-γ) and IgG were measured by enzyme-linked immunosorbent assay. All infected sheep had temperatures above 40 °C on days 3–4 post infection (PI). The maximum temperature was noted on day 7, and it remained high until day 21. The parasitaemia of T. lestoquardi infection increased from 0.01% (day 7 PI) to 3.3% (day 21 PI). The mean white blood cell (WBC), red blood cell (RBC), lymphocyte, neutrophil and platelet values slightly increased on day 2 PI and decreased by day 17 and day 21 PI. The percentage parasitaemia and fever had a negative correlation with the numbers of WBCs, RBCs, lymphocytes, neutrophils and platelets. The serum concentration of IL-6, TNF-α and IFN-γ cytokines increased and peaked on day 12 and thereafter decreased to levels lower than 0. Out of all tested cytokines, the concentration of IL-6 was significantly higher, as early as day 2 PI. No significant changes were observed for the IgG levels during the course of disease. A significant and strong correlation was observed between IL-6, TNF-α and IFN-γ values and a moderate correlation between IL-6 and the numbers of lymphocytes in the present study. A strong correlation was determined between the percentage parasitaemia and haematological parameters in T. lestoquardi-infected sheep. In addition, preliminary results indicate that the measurement of the serum concentrations of IL-6 in combination with haematological parameters could be considered a good marker to estimate the pathogenicity of T. lestoquardi strain.
Mostrar más [+] Menos [-]Brucellosis knowledge, attitudes and practices of a South African communal cattle keeper group Texto completo
2019
Alicia Cloete | Cornelia Gerstenberg | Natalie Mayet | Stefano Tempia
Brucellosis knowledge, attitudes and practices of a South African communal cattle keeper group Texto completo
2019
Alicia Cloete | Cornelia Gerstenberg | Natalie Mayet | Stefano Tempia
Brucellosis remains an animal and public health concern in South Africa, given the intensity and widespread distribution of outbreaks in cattle. We conducted a cross-sectional survey among cattle keepers in the Whittlesea community of the Eastern Cape Province of South Africa, which utilises communal grazing. Individual cattle keepers (N = 227) who attended prearranged meetings in selected villages were interviewed using a structured questionnaire to assess their knowledge, attitude and practices (KAP) regarding bovine brucellosis. We compared KAP scores between previous brucellosis-affected villages and unaffected villages. We compared attitude and practices scores between those who had heard of brucellosis and those who had not and between those above the 75th percentile knowledge score and those below. The KAP for the study population were described using frequency tables. Scores of different groups were compared using the Welch t-test or the Wilcoxon rank-sum test. Knowledge scores of those who had heard of brucellosis (60%) showed a bimodal distribution with a 0/18 primary peak and 5–6/18 secondary peak. Attitude scores showed a median of 7/14 (interquartile range [IQR] 6–9), with 98% requesting more information on brucellosis. Practices scores showed a median of 6/18 (IQR 3–8), with high-risk practices identified that could facilitate brucellosis transmission. There were significant differences in attitude and practices scores between the groups above and below the 75th percentile knowledge score. The community showed poor knowledge, poor to average practices and average to good attitude. Identified high-risk practices highlight the risk of potential introduction and transmission of brucellosis between cattle and zoonotic transmission to humans.
Mostrar más [+] Menos [-]Brucellosis knowledge, attitudes and practices of a South African communal cattle keeper group Texto completo
2019
Cloete, Alicia | Gerstenberg, Cornelia | Mayet, Natalie | Tempia, Stefano | South African Field Epidemiology Training Programme - National Institute for Communicable Diseases.
Brucellosis remains an animal and public health concern in South Africa, given the intensity and widespread distribution of outbreaks in cattle. We conducted a cross-sectional survey among cattle keepers in the Whittlesea community of the Eastern Cape Province of South Africa, which utilises communal grazing. Individual cattle keepers (N = 227) who attended prearranged meetings in selected villages were interviewed using a structured questionnaire to assess their knowledge, attitude and practices (KAP) regarding bovine brucellosis. We compared KAP scores between previous brucellosis-affected villages and unaffected villages. We compared attitude and practices scores between those who had heard of brucellosis and those who had not and between those above the 75th percentile knowledge score and those below. The KAP for the study population were described using frequency tables. Scores of different groups were compared using the Welch t-test or the Wilcoxon rank-sum test. Knowledge scores of those who had heard of brucellosis (60%) showed a bimodal distribution with a 0/18 primary peak and 5–6/18 secondary peak. Attitude scores showed a median of 7/14 (interquartile range [IQR] 6–9), with 98% requesting more information on brucellosis. Practices scores showed a median of 6/18 (IQR 3–8), with high-risk practices identified that could facilitate brucellosis transmission. There were significant differences in attitude and practices scores between the groups above and below the 75th percentile knowledge score. The community showed poor knowledge, poor to average practices and average to good attitude. Identified high-risk practices highlight the risk of potential introduction and transmission of brucellosis between cattle and zoonotic transmission to humans.
Mostrar más [+] Menos [-]A field study on the efficacy of ivermectin via subcutaneous route against chewing lice (Bovicola caprae) infestation in naturally infested goats Texto completo
2019
Y. Ajith | Umesh Dimri | A. Gopalakrishnan | Gopinath Devi
A field study on the efficacy of ivermectin via subcutaneous route against chewing lice (Bovicola caprae) infestation in naturally infested goats Texto completo
2019
Y. Ajith | Umesh Dimri | A. Gopalakrishnan | Gopinath Devi
Caprine pediculosis is an ectoparasitic disease of great concern among goat farmers in India. It may be caused by either sucking lice or chewing lice; the latter one results in severe skin lesions, leading to production loss. This study evaluated the effectiveness of the macrocytic lactone drug, ivermectin, administered via subcutaneous injection, against chewing lice Bovicola (Damalinia) caprae infestation in naturally infested goats. The study was conducted on 20 goats with severe B. caprae infestation. Animals of group A (n = 10) were treated using a single dose of ivermectin (200 µg/kg body weight) subcutaneously and animals of group B (n = 10) underwent placebo therapy using normal saline. The animals were examined on days 0, 3, 7, 14, 21, 28, 42 and 56 for lice counts. There was 100% elimination of lice in all animals of group A and effective protection from re-infection remained at least for 21 days. Considerable improvement in haematological parameters was also observed by day 21. Based on this study, ivermectin injected via a subcutaneous route can be used effectively for the therapeutic and prophylactic management of chewing lice infestation in goats maintained under an extensive grazing system.
Mostrar más [+] Menos [-]A field study on the efficacy of ivermectin via subcutaneous route against chewing lice (Bovicola caprae) infestation in naturally infested goats Texto completo
2019
Ajith, Y. | Dimri, Umesh | Gopalakrishnan, A. | Devi, Gopinath | DST, India
Caprine pediculosis is an ectoparasitic disease of great concern among goat farmers in India. It may be caused by either sucking lice or chewing lice; the latter one results in severe skin lesions, leading to production loss. This study evaluated the effectiveness of the macrocytic lactone drug, ivermectin, administered via subcutaneous injection, against chewing lice Bovicola (Damalinia) caprae infestation in naturally infested goats. The study was conducted on 20 goats with severe B. caprae infestation. Animals of group A (n = 10) were treated using a single dose of ivermectin (200 µg/kg body weight) subcutaneously and animals of group B (n = 10) underwent placebo therapy using normal saline. The animals were examined on days 0, 3, 7, 14, 21, 28, 42 and 56 for lice counts. There was 100% elimination of lice in all animals of group A and effective protection from re-infection remained at least for 21 days. Considerable improvement in haematological parameters was also observed by day 21. Based on this study, ivermectin injected via a subcutaneous route can be used effectively for the therapeutic and prophylactic management of chewing lice infestation in goats maintained under an extensive grazing system.
Mostrar más [+] Menos [-]Salmonellosis: Serotypes, prevalence and multi-drug resistant profiles of Salmonella enterica in selected poultry farms, Kwara State, North Central Nigeria Texto completo
2019
Akeem O. Ahmed | Moshood A. Raji | Paul H. Mamman | Clara N. Kwanashie | Ibrahim A. Raufu | Abdulfatai Aremu | Ganiu J. Akorede
Salmonellosis: Serotypes, prevalence and multi-drug resistant profiles of Salmonella enterica in selected poultry farms, Kwara State, North Central Nigeria Texto completo
2019
Akeem O. Ahmed | Moshood A. Raji | Paul H. Mamman | Clara N. Kwanashie | Ibrahim A. Raufu | Abdulfatai Aremu | Ganiu J. Akorede
Salmonellosis is a major threat facing the poultry industry globally. This study was conducted to investigate the level of Salmonella contaminations and determine the resistance pattern of isolates obtained from selected poultry farms in Kwara State, a transition state between southern and northern regions of Nigeria. A total of 900 samples were collected between January and August 2017, from the poultry environment, apparently including healthy and dead birds. Salmonella was isolated and identified using standard bacteriological methods. All presumptive Salmonella isolates were serotyped and tested for antimicrobial susceptibility using 11 different antimicrobials. A total of 58 (6.4%) Salmonella isolates were obtained, and the isolation rate was only statistically significant (p < 0.05) in live birds. The isolates comprised of 13 serovars. The three predominant serovars, Salmonella enterica ser. 6.7:d:- (29.0%), Salmonella Agama (28.0%) and Salmonella Typhimurium (16.0%), were isolated from all three sample types. Rare serovars like Salmonella Albany, Salmonella Colindale, Salmonella Istanbul, Salmonella Larochelle, Salmonella Nigeria and Salmonella Orion were also isolated in this study. A high frequency of resistance was generally observed with all the isolates exhibiting a total of (100%) resistance to ampicillin, cefotaxime and ceftazidime. This study documents the first predominant isolation of S. enterica ser. 6.7:d:- and S. Agama from chickens. It also documents the high frequency of fluoroquinolone and cephalosporins resistance of the isolates indicating the presence of selective pressure in the environment. Controls and targeted interventions against Salmonella and the frequent occurrence of antimicrobial resistance in chickens should be initiated to prevent the spread of this organism.
Mostrar más [+] Menos [-]Salmonellosis: Serotypes, prevalence and multi-drug resistant profiles of Salmonella enterica in selected poultry farms, Kwara State, North Central Nigeria Texto completo
2019
Ahmed, Akeem O. | Raji, Moshood A. | Mamman, Paul H. | Kwanashie, Clara N. | Raufu, Ibrahim A. | Aremu, Abdulfatai | Akorede, Ganiu J.
Salmonellosis is a major threat facing the poultry industry globally. This study was conducted to investigate the level of Salmonella contaminations and determine the resistance pattern of isolates obtained from selected poultry farms in Kwara State, a transition state between southern and northern regions of Nigeria. A total of 900 samples were collected between January and August 2017, from the poultry environment, apparently including healthy and dead birds. Salmonella was isolated and identified using standard bacteriological methods. All presumptive Salmonella isolates were serotyped and tested for antimicrobial susceptibility using 11 different antimicrobials. A total of 58 (6.4%) Salmonella isolates were obtained, and the isolation rate was only statistically significant (p 0.05) in live birds. The isolates comprised of 13 serovars. The three predominant serovars, Salmonella enterica ser. 6.7:d:- (29.0%), Salmonella Agama (28.0%) and Salmonella Typhimurium (16.0%), were isolated from all three sample types. Rare serovars like Salmonella Albany, Salmonella Colindale, Salmonella Istanbul, Salmonella Larochelle, Salmonella Nigeria and Salmonella Orion were also isolated in this study. A high frequency of resistance was generally observed with all the isolates exhibiting a total of (100%) resistance to ampicillin, cefotaxime and ceftazidime. This study documents the first predominant isolation of S. enterica ser. 6.7:d:- and S. Agama from chickens. It also documents the high frequency of fluoroquinolone and cephalosporins resistance of the isolates indicating the presence of selective pressure in the environment. Controls and targeted interventions against Salmonella and the frequent occurrence of antimicrobial resistance in chickens should be initiated to prevent the spread of this organism.
Mostrar más [+] Menos [-]Rift Valley fever virus in small ruminants in the Democratic Republic of the Congo Texto completo
2019
Georges M. Tshilenge | Mfumu L.K Mulumba | Gerald Misinzo | Rob Noad | William G. Dundon
Rift Valley fever virus in small ruminants in the Democratic Republic of the Congo Texto completo
2019
Georges M. Tshilenge | Mfumu L.K Mulumba | Gerald Misinzo | Rob Noad | William G. Dundon
Rift Valley fever (RVF) is a zoonotic viral disease caused by the RVF phlebovirus (RVFV) that infects a variety of animal species including sheep and goats. Sera (n = 893) collected between 2013 and 2015 from randomly selected indigenous sheep and goats in seven provinces of the Democratic Republic of the Congo (DRC) were tested for the presence of specific immunoglobulin G (IgG) and M (IgM) against RVFV, using two commercially available enzyme-linked immunosorbent assays. The reverse transcription polymerase chain reaction (RT-PCR) was also used to detect RVFV nucleic acid. There was significant variation in true seroprevalence of RVFV for both sheep and goats between the seven provinces investigated. Values ranged from 0.0 (95% confidence interval [CI] 0.0–6.55) to 23.81 (95% CI 12.03–41.76) for goat and 0.0 (95% CI 0.0–7.56) to 37.11 (95% CI 15.48–65.94) for sheep, respectively. One serum (1.85%) out of 54 that tested positive for IgG was found to be IgM-positive. This same sample was also positive by RT-PCR indicating an active or recent infection. These findings report the presence of RVFV in small ruminants in the DRC for the first time and indicate variations in exposure to the virus in different parts of the country.
Mostrar más [+] Menos [-]Rift Valley fever virus in small ruminants in the Democratic Republic of the Congo Texto completo
2019
Tshilenge, Georges M. | Mulumba, Mfumu L.K | Misinzo, Gerald | Noad, Rob | Dundon, William G. | Wellcome Trust
Rift Valley fever (RVF) is a zoonotic viral disease caused by the RVF phlebovirus (RVFV) that infects a variety of animal species including sheep and goats. Sera (n = 893) collected between 2013 and 2015 from randomly selected indigenous sheep and goats in seven provinces of the Democratic Republic of the Congo (DRC) were tested for the presence of specific immunoglobulin G (IgG) and M (IgM) against RVFV, using two commercially available enzyme-linked immunosorbent assays. The reverse transcription polymerase chain reaction (RT-PCR) was also used to detect RVFV nucleic acid. There was significant variation in true seroprevalence of RVFV for both sheep and goats between the seven provinces investigated. Values ranged from 0.0 (95% confidence interval [CI] 0.0–6.55) to 23.81 (95% CI 12.03–41.76) for goat and 0.0 (95% CI 0.0–7.56) to 37.11 (95% CI 15.48–65.94) for sheep, respectively. One serum (1.85%) out of 54 that tested positive for IgG was found to be IgM-positive. This same sample was also positive by RT-PCR indicating an active or recent infection. These findings report the presence of RVFV in small ruminants in the DRC for the first time and indicate variations in exposure to the virus in different parts of the country.
Mostrar más [+] Menos [-]Acaricidal activity of the aqueous and hydroethanolic extracts of 15 South African plants against Rhipicephalus turanicus and their toxicity on human liver and kidney cells Texto completo
2019
Gerda Fouche | Olubukola T. Adenubi | Tlabo Leboho | Lyndy J. McGaw | Vinny Naidoo | Kevin W. Wellington | Jacobus N. Eloff
Acaricidal activity of the aqueous and hydroethanolic extracts of 15 South African plants against Rhipicephalus turanicus and their toxicity on human liver and kidney cells Texto completo
2019
Gerda Fouche | Olubukola T. Adenubi | Tlabo Leboho | Lyndy J. McGaw | Vinny Naidoo | Kevin W. Wellington | Jacobus N. Eloff
Hot water and hydroethanolic (70:30) extracts were prepared from 15 plant species, which were investigated to discover eco-friendly and less expensive tick control methods as an alternative to synthetic acaricides. A contact bioassay was used to determine the acaricidal activity of these extracts against the cattle tick, Rhipicephalus turanicus (Acari: Ixodidae) at a concentration of 20% (200 mg/mL). The hydroethanolic extracts had better activity than the hot water extracts against R. turanicus. The hydroethanolic extract from Tabernaemontana elegans (leaves) had the best mortality (87.0%). This was followed by Calpurnia aurea (stems) with a mortality of 75.0%, Schkuhria pinnata (whole plant) with a mortality of 67.0% and Aloe rupestris (leaves) with a mortality of 66.6%. The toxicity of the plant extracts was also investigated and it was found that most of the hydroethanolic and hot water extracts were either safe or very safe on human Vero kidney and liver HepG2 cells. From this study, it was evident that botanicals have the potential to be developed as environmentally benign natural acaricides against R. turanicus.
Mostrar más [+] Menos [-]Acaricidal activity of the aqueous and hydroethanolic extracts of 15 South African plants against Rhipicephalus turanicus and their toxicity on human liver and kidney cells Texto completo
2019
Fouche, Gerda | Adenubi, Olubukola T. | Leboho, Tlabo | McGaw, Lyndy J. | Naidoo, Vinny | Wellington, Kevin W. | Eloff, Jacobus N. | Technology Innovation Agency (TIA) of South Africa for financial support.
Hot water and hydroethanolic (70:30) extracts were prepared from 15 plant species, which were investigated to discover eco-friendly and less expensive tick control methods as an alternative to synthetic acaricides. A contact bioassay was used to determine the acaricidal activity of these extracts against the cattle tick, Rhipicephalus turanicus (Acari: Ixodidae) at a concentration of 20% (200 mg/mL). The hydroethanolic extracts had better activity than the hot water extracts against R. turanicus. The hydroethanolic extract from Tabernaemontana elegans (leaves) had the best mortality (87.0%). This was followed by Calpurnia aurea (stems) with a mortality of 75.0%, Schkuhria pinnata (whole plant) with a mortality of 67.0% and Aloe rupestris (leaves) with a mortality of 66.6%. The toxicity of the plant extracts was also investigated and it was found that most of the hydroethanolic and hot water extracts were either safe or very safe on human Vero kidney and liver HepG2 cells. From this study, it was evident that botanicals have the potential to be developed as environmentally benign natural acaricides against R. turanicus.
Mostrar más [+] Menos [-]Seasonal activity of ticks infesting domestic dogs in Bejaia province, Northern Algeria Texto completo
2019
Rosa Kebbi | Mohamed Nait-Mouloud | Lila Hassissen | Abdelhanine Ayad
Seasonal activity of ticks infesting domestic dogs in Bejaia province, Northern Algeria Texto completo
2019
Rosa Kebbi | Mohamed Nait-Mouloud | Lila Hassissen | Abdelhanine Ayad
This epidemiological study aimed to determine the species of tick infestation in dogs, their prevalence and dynamic in the Bejaia province, northeastern Algeria. A total of 631 dogs were examined from different localities of the Bejaia province between March 2016 and February 2017. Of the 631 examined dogs, 15% were infested with one or more tick species. A total of 339 adult ticks were collected and identified, including 199 male tick species and 140 female tick species. Our results revealed that most of these were Rhipicephalus species, with Rhipicephalus sanguineus (51.32%) being the most prevalent followed by Rhipicephalus bursa (35.1%) and Rhipicephalus turanicus (12.98%). Ixodes ricinus represented only 0.6% of all ticks collected. The highest infested seasons were spring (22.55%) and summer (22.54%) and the lowest infested seasons were autumn (8.62%) and winter ( 0.9%). There is no significant difference between the sex of the animal and the prevalence of infestation (p = 0.837). Also, the prevalence of infestation by ticks in young animals was higher than that in adult animals (p = 0.550). A significant difference between the prevalence of infestation and animal breed was observed (p = 0.042). This study is the first epidemiological investigation conducted on the prevalence of hard ticks infesting domestic dogs in Bejaia (northeastern Algeria) based on conventional methods. It is therefore necessary to implement an effective tick control strategy during infestation periods in order to prevent vector-borne diseases.
Mostrar más [+] Menos [-]Seasonal activity of ticks infesting domestic dogs in Bejaia province, Northern Algeria Texto completo
2019
Kebbi, Rosa | Nait-Mouloud, Mohamed | Hassissen, Lila | Ayad, Abdelhanine
This epidemiological study aimed to determine the species of tick infestation in dogs, their prevalence and dynamic in the Bejaia province, northeastern Algeria. A total of 631 dogs were examined from different localities of the Bejaia province between March 2016 and February 2017. Of the 631 examined dogs, 15% were infested with one or more tick species. A total of 339 adult ticks were collected and identified, including 199 male tick species and 140 female tick species. Our results revealed that most of these were Rhipicephalus species, with Rhipicephalus sanguineus (51.32%) being the most prevalent followed by Rhipicephalus bursa (35.1%) and Rhipicephalus turanicus (12.98%). Ixodes ricinus represented only 0.6% of all ticks collected. The highest infested seasons were spring (22.55%) and summer (22.54%) and the lowest infested seasons were autumn (8.62%) and winter ( 0.9%). There is no significant difference between the sex of the animal and the prevalence of infestation (p = 0.837). Also, the prevalence of infestation by ticks in young animals was higher than that in adult animals (p = 0.550). A significant difference between the prevalence of infestation and animal breed was observed (p = 0.042). This study is the first epidemiological investigation conducted on the prevalence of hard ticks infesting domestic dogs in Bejaia (northeastern Algeria) based on conventional methods. It is therefore necessary to implement an effective tick control strategy during infestation periods in order to prevent vector-borne diseases.
Mostrar más [+] Menos [-]Phylogenetic studies of larval digenean trematodes from freshwater snails and fish species in the proximity of Tshwane metropolitan, South Africa Texto completo
2019
Esmey B. Moema | Pieter H. King | Johnny N. Rakgole
Phylogenetic studies of larval digenean trematodes from freshwater snails and fish species in the proximity of Tshwane metropolitan, South Africa Texto completo
2019
Esmey B. Moema | Pieter H. King | Johnny N. Rakgole
The classification and description of digenean trematodes are commonly accomplished by using morphological features, especially in adult stages. The aim of this study was to provide an analysis of the genetic composition of larval digenean trematodes using polymerase chain reaction (PCR) and sequence analysis. Deoxyribonucleic acid (DNA) was extracted from clinostomatid metacercaria, 27-spined echinostomatid redia, avian schistosome cercaria and strigeid metacercaria from various dams in the proximity of Tshwane metropolitan, South Africa. Polymerase chain reaction was performed using the extracted DNA with primers targeting various regions within the larval digenean trematodes’ genomes. Agarose gel electrophoresis technique was used to visualise the PCR products. The PCR products were sequenced on an Applied Bioinformatics (ABI) genetic analyser platform. Genetic information obtained from this study had a higher degree of discrimination than the morphological characteristics of seemingly similar organisms.
Mostrar más [+] Menos [-]Phylogenetic studies of larval digenean trematodes from freshwater snails and fish species in the proximity of Tshwane metropolitan, South Africa Texto completo
2019
Moema, Esmey B. | King, Pieter H. | Rakgole, Johnny N.
The classification and description of digenean trematodes are commonly accomplished by using morphological features, especially in adult stages. The aim of this study was to provide an analysis of the genetic composition of larval digenean trematodes using polymerase chain reaction (PCR) and sequence analysis. Deoxyribonucleic acid (DNA) was extracted from clinostomatid metacercaria, 27-spined echinostomatid redia, avian schistosome cercaria and strigeid metacercaria from various dams in the proximity of Tshwane metropolitan, South Africa. Polymerase chain reaction was performed using the extracted DNA with primers targeting various regions within the larval digenean trematodes’ genomes. Agarose gel electrophoresis technique was used to visualise the PCR products. The PCR products were sequenced on an Applied Bioinformatics (ABI) genetic analyser platform. Genetic information obtained from this study had a higher degree of discrimination than the morphological characteristics of seemingly similar organisms.
Mostrar más [+] Menos [-]