An innovative training program entitled “AgSecure Africa ProgrammeTM” was developed in partnershi... more An innovative training program entitled “AgSecure Africa ProgrammeTM” was developed in partnership with the South African Agricultural Research Council-Onderstepoort Veterinary Research (ARC-OVR) to train veterinarians, animal health technicians, researchers and laboratory personnel. Three blended courses consisting of both virtual and in-person delivery were provided with the intent of contributing to the better prevention, detection and control of infectious diseases of livestock and poultry of significant importance for the region with a strong emphasis on transboundary animal diseases. A “train the trainer” model of instruction was employed to equip participants with the ability to train and share knowledge with colleagues and small-holder farmers in their various communities and regions. The design of this program was to increase the capacity of veterinarians and veterinary diagnosticians to safely and accurately diagnose infectious livestock diseases and to also empower small-...
The Onderstepoort journal of veterinary research, 1987
The sequential development of C. ruminantium (Kwanyanga and Kümm isolates) was followed in caprin... more The sequential development of C. ruminantium (Kwanyanga and Kümm isolates) was followed in caprine leukocyte cultures by light microscopy, direct immunofluorescent microscopy (DFA), indirect immunoflourescent microscopy (IFA) and transmission electron microscopy (TEM). During the febrile response, one to several small cocci, large ring forms or rods were observed in neutrophils in blood smears and cytopreparations of neutrophil fractions using Diff Quik stain, Giemsa stain, DFA and TEM. One to several C. ruminantium colonies were seen in up to 35% of neutrophils maintained in vitro for 18 h to 5 days. The organisms were located in neutrophil phagosomes by TEM and were enveloped by two trilamellar unit membranes. Initially, C. ruminantium was tightly enclosed within phagosomes. At 20 h of incubation, organisms were frequently observed undergoing binary fission within enlarged phagosomal vacuoles. At later time periods, neutrophils harboured fully formed colonies (morula) containing n...
The cDNA coding for the soluble form of bovine stem cell factor (boSCFAla165) was cloned and reco... more The cDNA coding for the soluble form of bovine stem cell factor (boSCFAla165) was cloned and recombinant protein was produced in bacteria as a histidine tagged-protein. The protein was purified from the inclusion bodies in one step by metal chelation chromatography under denaturing conditions. Recombinant bovine SCF was shown to act synergistically with interleukin 3 (IL-3) and erythropoietin (EPO) in stimulating the growth of bone marrow progenitor cells such as colony forming units-granulocyte macrophage (CFU-GM) and burst forming units-erythroid (BFU-E). Analysis of SCF mRNA expression by reverse transcription-polymerase chain reaction (RT-PCR) revealed that the transcripts were detectable in bone marrow, lymph nodes and spleen of cattle, and that the level of transcription was upregulated in lymph nodes of cattle infected with Trypanosoma congolense. Two isoforms of SCF mRNA were amplified by RT-PCR. The availability of recombinant bovine SCF provides a valuable tool for studying the role of SCF in the development, growth and differentiation of bovine hematopoietic cells.
A bovine cDNA encoding erythropoietin (Epo) was isolated by polymerase chain reaction (PCR) ampli... more A bovine cDNA encoding erythropoietin (Epo) was isolated by polymerase chain reaction (PCR) amplification and screening of a bovine kidney cDNA library. The sequenced cDNA has a length of 1312 bp and an open reading frame that encodes a predicted 192-amino-acid (aa) protein, including a putative signal sequence of 25 aa. A mature protein of 167 aa (18.4 kDa) results upon cleavage of the putative signal peptide. The deduced bovine mature Epo peptide exhibits 96, 88, 83, 82 and 79% sequence identity to that of sheep, swine, human, monkey and rat, respectively. The expression of the bovine Epo gene in tissues from a severely anemic calf, bovine fetus and a healthy steer was analysed by a competitive RT-PCR method. In kidneys of the severely anemic calf, Epo mRNA levels increased 60-fold relative to that from the kidneys of the healthy steer. Epo mRNA levels were threefold higher in the liver of the bovine fetus than that in its kidneys. Low levels of Epo transcripts were detected in RNA from spleen of the severely anemic calf and the bovine fetus. No Epo transcripts were detectable in spleen from the healthy steer.
Medicinal plants with anthelmintic properties are an alternative to the chemical fight against sm... more Medicinal plants with anthelmintic properties are an alternative to the chemical fight against small ruminant’s gastrointestinal nematodes. In order to broaden the spectrum of medicinal plants with anthelmintic properties, ovicidal activity and L3 larvae exsheathment of C. sesamoïdes Endl and S. hermonthica (Deli) Benth, aqueous extracts has been done on H contortus egg and L3 larvae. Three concentrations, 3.12 mg / ml, 6.25 mg / ml, 12.5 mg / ml of each plant extract were used to assess the inhibition of fresh egg hatching and larval paralysis as well as the 'inhibition of L3 larvae exsheathment. A negative control (PBS1x) and a positive control (levamisole, 2.5 mg / ml) were constituted for the fresh egg hatching inhibition assessment while only the negative control (PBS1x) was constituted to evaluate the inhibition of L3 Larvae exsheathment.1 ml of each concentration was contacted with 1 ml of the egg solution and then incubated for 48 hours at 27 ° C in petri dishes (60X15 C...
Bovine babesiosis is a reportable transboundary animal disease caused by Babesia bovis and Babesi... more Bovine babesiosis is a reportable transboundary animal disease caused by Babesia bovis and Babesiabigemina in the Americas where these apicomplexan protozoa are transmitted by the invasive cattle fever ticks Rhipicephalus (Boophilus) microplus and Rhipicephalus(Boophilus) annulatus. In countries like Mexico where cattle fever ticks remain endemic, bovine babesiosis is detrimental to cattle health and results in a significant economic cost to the livestock industry. These cattle disease vectors continue to threaten the U.S. cattle industry despite their elimination through efforts of the Cattle Fever Tick Eradication Program. Mexico and the U.S. share a common interest in managing cattle fever ticks through their economically important binational cattle trade. Here, we report the outcomes of a meeting where stakeholders from Mexico and the U.S. representing the livestock and pharmaceutical industry, regulatory agencies, and research institutions gathered to discuss research and knowl...
... College of Veterinary Medicine, University of Georgia, Athens, Georgia 30602 (Submitted for p... more ... College of Veterinary Medicine, University of Georgia, Athens, Georgia 30602 (Submitted for publication December 31, 1973) LOGAN, LINDA L., AND ... Sterile roller culture flasks (670 cm2 growth area) were seeded with Vero cells in Eagle's minimum essential medium sup ...
An innovative training program entitled “AgSecure Africa ProgrammeTM” was developed in partnershi... more An innovative training program entitled “AgSecure Africa ProgrammeTM” was developed in partnership with the South African Agricultural Research Council-Onderstepoort Veterinary Research (ARC-OVR) to train veterinarians, animal health technicians, researchers and laboratory personnel. Three blended courses consisting of both virtual and in-person delivery were provided with the intent of contributing to the better prevention, detection and control of infectious diseases of livestock and poultry of significant importance for the region with a strong emphasis on transboundary animal diseases. A “train the trainer” model of instruction was employed to equip participants with the ability to train and share knowledge with colleagues and small-holder farmers in their various communities and regions. The design of this program was to increase the capacity of veterinarians and veterinary diagnosticians to safely and accurately diagnose infectious livestock diseases and to also empower small-...
The Onderstepoort journal of veterinary research, 1987
The sequential development of C. ruminantium (Kwanyanga and Kümm isolates) was followed in caprin... more The sequential development of C. ruminantium (Kwanyanga and Kümm isolates) was followed in caprine leukocyte cultures by light microscopy, direct immunofluorescent microscopy (DFA), indirect immunoflourescent microscopy (IFA) and transmission electron microscopy (TEM). During the febrile response, one to several small cocci, large ring forms or rods were observed in neutrophils in blood smears and cytopreparations of neutrophil fractions using Diff Quik stain, Giemsa stain, DFA and TEM. One to several C. ruminantium colonies were seen in up to 35% of neutrophils maintained in vitro for 18 h to 5 days. The organisms were located in neutrophil phagosomes by TEM and were enveloped by two trilamellar unit membranes. Initially, C. ruminantium was tightly enclosed within phagosomes. At 20 h of incubation, organisms were frequently observed undergoing binary fission within enlarged phagosomal vacuoles. At later time periods, neutrophils harboured fully formed colonies (morula) containing n...
The cDNA coding for the soluble form of bovine stem cell factor (boSCFAla165) was cloned and reco... more The cDNA coding for the soluble form of bovine stem cell factor (boSCFAla165) was cloned and recombinant protein was produced in bacteria as a histidine tagged-protein. The protein was purified from the inclusion bodies in one step by metal chelation chromatography under denaturing conditions. Recombinant bovine SCF was shown to act synergistically with interleukin 3 (IL-3) and erythropoietin (EPO) in stimulating the growth of bone marrow progenitor cells such as colony forming units-granulocyte macrophage (CFU-GM) and burst forming units-erythroid (BFU-E). Analysis of SCF mRNA expression by reverse transcription-polymerase chain reaction (RT-PCR) revealed that the transcripts were detectable in bone marrow, lymph nodes and spleen of cattle, and that the level of transcription was upregulated in lymph nodes of cattle infected with Trypanosoma congolense. Two isoforms of SCF mRNA were amplified by RT-PCR. The availability of recombinant bovine SCF provides a valuable tool for studying the role of SCF in the development, growth and differentiation of bovine hematopoietic cells.
A bovine cDNA encoding erythropoietin (Epo) was isolated by polymerase chain reaction (PCR) ampli... more A bovine cDNA encoding erythropoietin (Epo) was isolated by polymerase chain reaction (PCR) amplification and screening of a bovine kidney cDNA library. The sequenced cDNA has a length of 1312 bp and an open reading frame that encodes a predicted 192-amino-acid (aa) protein, including a putative signal sequence of 25 aa. A mature protein of 167 aa (18.4 kDa) results upon cleavage of the putative signal peptide. The deduced bovine mature Epo peptide exhibits 96, 88, 83, 82 and 79% sequence identity to that of sheep, swine, human, monkey and rat, respectively. The expression of the bovine Epo gene in tissues from a severely anemic calf, bovine fetus and a healthy steer was analysed by a competitive RT-PCR method. In kidneys of the severely anemic calf, Epo mRNA levels increased 60-fold relative to that from the kidneys of the healthy steer. Epo mRNA levels were threefold higher in the liver of the bovine fetus than that in its kidneys. Low levels of Epo transcripts were detected in RNA from spleen of the severely anemic calf and the bovine fetus. No Epo transcripts were detectable in spleen from the healthy steer.
Medicinal plants with anthelmintic properties are an alternative to the chemical fight against sm... more Medicinal plants with anthelmintic properties are an alternative to the chemical fight against small ruminant’s gastrointestinal nematodes. In order to broaden the spectrum of medicinal plants with anthelmintic properties, ovicidal activity and L3 larvae exsheathment of C. sesamoïdes Endl and S. hermonthica (Deli) Benth, aqueous extracts has been done on H contortus egg and L3 larvae. Three concentrations, 3.12 mg / ml, 6.25 mg / ml, 12.5 mg / ml of each plant extract were used to assess the inhibition of fresh egg hatching and larval paralysis as well as the 'inhibition of L3 larvae exsheathment. A negative control (PBS1x) and a positive control (levamisole, 2.5 mg / ml) were constituted for the fresh egg hatching inhibition assessment while only the negative control (PBS1x) was constituted to evaluate the inhibition of L3 Larvae exsheathment.1 ml of each concentration was contacted with 1 ml of the egg solution and then incubated for 48 hours at 27 ° C in petri dishes (60X15 C...
Bovine babesiosis is a reportable transboundary animal disease caused by Babesia bovis and Babesi... more Bovine babesiosis is a reportable transboundary animal disease caused by Babesia bovis and Babesiabigemina in the Americas where these apicomplexan protozoa are transmitted by the invasive cattle fever ticks Rhipicephalus (Boophilus) microplus and Rhipicephalus(Boophilus) annulatus. In countries like Mexico where cattle fever ticks remain endemic, bovine babesiosis is detrimental to cattle health and results in a significant economic cost to the livestock industry. These cattle disease vectors continue to threaten the U.S. cattle industry despite their elimination through efforts of the Cattle Fever Tick Eradication Program. Mexico and the U.S. share a common interest in managing cattle fever ticks through their economically important binational cattle trade. Here, we report the outcomes of a meeting where stakeholders from Mexico and the U.S. representing the livestock and pharmaceutical industry, regulatory agencies, and research institutions gathered to discuss research and knowl...
... College of Veterinary Medicine, University of Georgia, Athens, Georgia 30602 (Submitted for p... more ... College of Veterinary Medicine, University of Georgia, Athens, Georgia 30602 (Submitted for publication December 31, 1973) LOGAN, LINDA L., AND ... Sterile roller culture flasks (670 cm2 growth area) were seeded with Vero cells in Eagle's minimum essential medium sup ...
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