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Challenges for controlling bovine tuberculosis in South Africa Texto completo
2020
Arnot, Luke F.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies,University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases) | Michel, Anita(University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases)
Challenges for controlling bovine tuberculosis in South Africa Texto completo
2020
Arnot, Luke F.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies,University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases) | Michel, Anita(University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases)
All effects taken together, bovine tuberculosis (bTB) has a long-term detrimental effect on bovine herds and many wildlife species in South Africa. The disease is not only found in domestic cattle but also in African buffaloes and has to date been diagnosed in 21 wildlife species, including several rare and endangered species, thus having a potentially serious effect on conservation and biodiversity. In cattle, bTB is mostly characterised by sporadic outbreaks, but bovine herds chronically infected with the clinical disease are not uncommon. Presently, the recognised bTB control strategy in South Africa is based on 'test and slaughter', using the intradermal tuberculin test, followed by the slaughter of animals that have tested positive. Affected herds are placed under veterinary quarantine with movement restrictions until the outbreak is eradicated; this can take several years or last indefinitely if the outbreak cannot be eradicated. The same measures apply to infected buffalo populations, often with no prospect of ever being eradicated. This strategy is neither practical nor viable in the context of a communal farming system and becomes unethical when dealing with valuable wildlife reservoir hosts. Transmission of bTB between wildlife and cattle has been demonstrated and emphasises the need for an effective, affordable and culturally acceptable control strategy to curb the spread of bTB in South Africa. In countries with similar challenges, vaccination has been used and found to be promising for treating wild and domestic reservoir species and may hence be of value as a complementary tool for bTB control in South Africa.
Mostrar más [+] Menos [-]Challenges for controlling bovine tuberculosis in South Africa Texto completo
2020
Luke F. Arnot | Anita Michel
All effects taken together, bovine tuberculosis (bTB) has a long-term detrimental effect on bovine herds and many wildlife species in South Africa. The disease is not only found in domestic cattle but also in African buffaloes and has to date been diagnosed in 21 wildlife species, including several rare and endangered species, thus having a potentially serious effect on conservation and biodiversity. In cattle, bTB is mostly characterised by sporadic outbreaks, but bovine herds chronically infected with the clinical disease are not uncommon. Presently, the recognised bTB control strategy in South Africa is based on ‘test and slaughter’, using the intradermal tuberculin test, followed by the slaughter of animals that have tested positive. Affected herds are placed under veterinary quarantine with movement restrictions until the outbreak is eradicated; this can take several years or last indefinitely if the outbreak cannot be eradicated. The same measures apply to infected buffalo populations, often with no prospect of ever being eradicated. This strategy is neither practical nor viable in the context of a communal farming system and becomes unethical when dealing with valuable wildlife reservoir hosts. Transmission of bTB between wildlife and cattle has been demonstrated and emphasises the need for an effective, affordable and culturally acceptable control strategy to curb the spread of bTB in South Africa. In countries with similar challenges, vaccination has been used and found to be promising for treating wild and domestic reservoir species and may hence be of value as a complementary tool for bTB control in South Africa.
Mostrar más [+] Menos [-]Genetic diversity of Ehrlichia ruminantium field strains from selected farms in South Africa Texto completo
2020
Steyn, Helena C.(Onderstepoort Veterinary Research Vaccine Development and Diagnostics) | Pretorius, Alri(Onderstepoort Veterinary Research Vaccine Development and Diagnostics)
Genetic diversity of Ehrlichia ruminantium field strains from selected farms in South Africa Texto completo
2020
Steyn, Helena C.(Onderstepoort Veterinary Research Vaccine Development and Diagnostics) | Pretorius, Alri(Onderstepoort Veterinary Research Vaccine Development and Diagnostics)
Heartwater is a tick-borne disease caused by the intracellular rickettsial parasite Ehrlichia ruminantium and transmitted by Amblyomma hebraeum ticks. Heartwater is problematic in endemic areas because it causes high mortality in ruminants and leads to economic losses that threaten productivity and food security. This may indicate that there is augmented genetic diversity in the field, which may result in isolates that are more virulent than the Ball3 and Welgevonden isolates. The genetic diversity of E. ruminantium was investigated in this study, focussing on the pCS20 gene region and four polymorphic open reading frames (ORFs) identified by subtractive hybridisation. The 16S ribosomal ribonucleic acid gene confirmed E. ruminantium in brain, blood and tick genomic deoxyribonucleic acid samples (n = 3792) collected from 122 farms that were randomly selected from seven provinces of South Africa where heartwater is endemic. The conserved E. ruminantium pCS20 quantitative polymerase chain reaction (qPCR) assay was used to scan all collected field samples. A total of 433 samples tested positive with the qPCR using the pCS20 gene region, of which 167 were sequenced. The known stocks and field samples were analysed, and phylogenetic trees were generated from consensus sequences. A total of 25 new clades were identified; of these, nine isolates from infected blood could be propagated in cell cultures. These clades were not geographically confined to a certain area but were distributed amongst heartwater-endemic areas in South Africa. Thus, the knowledge of strain diversity of E. ruminantium is essential for control of heartwater and provides a basis for further vaccine development.
Mostrar más [+] Menos [-]Genetic diversity of Ehrlichia ruminantium field strains from selected farms in South Africa Texto completo
2020
Helena C. Steyn | Alri Pretorius
Heartwater is a tick-borne disease caused by the intracellular rickettsial parasite Ehrlichia ruminantium and transmitted by Amblyomma hebraeum ticks. Heartwater is problematic in endemic areas because it causes high mortality in ruminants and leads to economic losses that threaten productivity and food security. This may indicate that there is augmented genetic diversity in the field, which may result in isolates that are more virulent than the Ball3 and Welgevonden isolates. The genetic diversity of E. ruminantium was investigated in this study, focussing on the pCS20 gene region and four polymorphic open reading frames (ORFs) identified by subtractive hybridisation. The 16S ribosomal ribonucleic acid gene confirmed E. ruminantium in brain, blood and tick genomic deoxyribonucleic acid samples (n = 3792) collected from 122 farms that were randomly selected from seven provinces of South Africa where heartwater is endemic. The conserved E. ruminantium pCS20 quantitative polymerase chain reaction (qPCR) assay was used to scan all collected field samples. A total of 433 samples tested positive with the qPCR using the pCS20 gene region, of which 167 were sequenced. The known stocks and field samples were analysed, and phylogenetic trees were generated from consensus sequences. A total of 25 new clades were identified; of these, nine isolates from infected blood could be propagated in cell cultures. These clades were not geographically confined to a certain area but were distributed amongst heartwater-endemic areas in South Africa. Thus, the knowledge of strain diversity of E. ruminantium is essential for control of heartwater and provides a basis for further vaccine development.
Mostrar más [+] Menos [-]Study on the prevalence and genetic diversity of Eimeria species from broilers and free-range chickens in KwaZulu-Natal province, South Africa Texto completo
2020
Fatoba, Abiodun J.(University of KwaZulu-Natal College of Agriculture, Engineering and Sciences School of Life Sciences) | Zishiri, Oliver T.(University of KwaZulu-Natal College of Agriculture, Engineering and Sciences School of Life Sciences) | Blake, Damer P.(The Royal Veterinary College Department of Pathobiology and Population Sciences) | Peters, Sunday O.(Berry College Department of Animal Science) | Lebepe, Jeffrey(University of KwaZulu-Natal School of Life Sciences, College of Agriculture, Engineering and Sciences Department of Biodiversity and Evolutionary Biology) | Mukaratirwa, Samson(University of KwaZulu-Natal College of Agriculture, Engineering and Sciences School of Life Sciences) | Adeleke, Matthew A.(University of KwaZulu-Natal College of Agriculture, Engineering and Sciences School of Life Sciences)
Study on the prevalence and genetic diversity of Eimeria species from broilers and free-range chickens in KwaZulu-Natal province, South Africa Texto completo
2020
Fatoba, Abiodun J.(University of KwaZulu-Natal College of Agriculture, Engineering and Sciences School of Life Sciences) | Zishiri, Oliver T.(University of KwaZulu-Natal College of Agriculture, Engineering and Sciences School of Life Sciences) | Blake, Damer P.(The Royal Veterinary College Department of Pathobiology and Population Sciences) | Peters, Sunday O.(Berry College Department of Animal Science) | Lebepe, Jeffrey(University of KwaZulu-Natal School of Life Sciences, College of Agriculture, Engineering and Sciences Department of Biodiversity and Evolutionary Biology) | Mukaratirwa, Samson(University of KwaZulu-Natal College of Agriculture, Engineering and Sciences School of Life Sciences) | Adeleke, Matthew A.(University of KwaZulu-Natal College of Agriculture, Engineering and Sciences School of Life Sciences)
This study was conducted from January to October 2018 with the objective to determine the prevalence and genetic diversity of Eimeria species in broiler and free-range chickens in KwaZulu-Natal province, South Africa. A total of 342 faecal samples were collected from 12 randomly selected healthy broiler chicken farms and 40 free-range chickens from 10 different locations. Faecal samples were screened for the presence of Eimeria oocysts using a standard flotation method. The species of Eimeria isolates were confirmed by amplification of the internal transcribed spacer 1 (ITS-1) partial region and sequences analysis. Among broiler and free-ranging chickens, 19 out of 41 pens (46.3%) and 25 out of 42 faecal samples (59.5%) were positive for Eimeria infection. Molecular detection revealed the following species: Eimeria maxima, Eimeria tenella, Eimeria acervulina, Eimeria brunetti and Eimeria mitis in all the samples screened. Similarly, polymerase chain reaction assays specific for three cryptic Eimeria operational taxonomic units were negative for all the samples. Phylogenetic analysis of the ITS-1 sequences supported species identity with the greatest variation detected for E. mitis. This study provides information on the range and identity of Eimeria species, and their genetic relatedness, circulating in commercially reared broilers and free-ranging chickens from different locations in KwaZulu-Natal province.
Mostrar más [+] Menos [-]Study on the prevalence and genetic diversity of Eimeria species from broilers and free-range chickens in KwaZulu-Natal province, South Africa Texto completo
2020
Abiodun J. Fatoba | Oliver T. Zishiri | Damer P. Blake | Sunday O. Peters | Jeffrey Lebepe | Samson Mukaratirwa | Matthew A. Adeleke
This study was conducted from January to October 2018 with the objective to determine the prevalence and genetic diversity of Eimeria species in broiler and free-range chickens in KwaZulu-Natal province, South Africa. A total of 342 faecal samples were collected from 12 randomly selected healthy broiler chicken farms and 40 free-range chickens from 10 different locations. Faecal samples were screened for the presence of Eimeria oocysts using a standard flotation method. The species of Eimeria isolates were confirmed by amplification of the internal transcribed spacer 1 (ITS-1) partial region and sequences analysis. Among broiler and free-ranging chickens, 19 out of 41 pens (46.3%) and 25 out of 42 faecal samples (59.5%) were positive for Eimeria infection. Molecular detection revealed the following species: Eimeria maxima, Eimeria tenella, Eimeria acervulina, Eimeria brunetti and Eimeria mitis in all the samples screened. Similarly, polymerase chain reaction assays specific for three cryptic Eimeria operational taxonomic units were negative for all the samples. Phylogenetic analysis of the ITS-1 sequences supported species identity with the greatest variation detected for E. mitis. This study provides information on the range and identity of Eimeria species, and their genetic relatedness, circulating in commercially reared broilers and free-ranging chickens from different locations in KwaZulu-Natal province.
Mostrar más [+] Menos [-]Detection and characterisation of sheep-associated malignant catarrhal fever infection from ruminants by using tegument and gB gene sequences of OvHV-2 Texto completo
2020
Tuba Ç. Oğuzoğlu | Seçkin Salar | Ece Adıgüzel | Cansu Demirden | Onur Ülgenalp
In this study, positive blood and organ samples were obtained from different mixed herds of sheep and cattle against ovine herpesvirus 2 (OvHV-2) infection. Target-positive DNA was sequenced and compared with worldwide distributed OvHV-2 sequences. Tegument gene (422 base pairs) and glycoprotein B (gB) gene (2800 base pairs) amplicons of OvHV-2 genome were used for understanding of epidemiology of malignant catarrhal fever (MCF) infection in Turkey. The results of nucleotide sequencing of polymerase chain reaction (PCR) products indicated presence of sheep-associated form for MCF infection in Turkey. Although the obtained sequences were genetically different from each other, it was found that genetic variations were limited.
Mostrar más [+] Menos [-]A review of Listeria monocytogenes from meat and meat products: Epidemiology, virulence factors, antimicrobial resistance and diagnosis Texto completo
2020
Itumeleng Matle | Khanyisile R. Mbatha | Evelyn Madoroba
A review of Listeria monocytogenes from meat and meat products: Epidemiology, virulence factors, antimicrobial resistance and diagnosis Texto completo
2020
Itumeleng Matle | Khanyisile R. Mbatha | Evelyn Madoroba
Listeria monocytogenes is a zoonotic food-borne pathogen that is associated with serious public health and economic implications. In animals, L. monocytogenes can be associated with clinical listeriosis, which is characterised by symptoms such as abortion, encephalitis and septicaemia. In human beings, listeriosis symptoms include encephalitis, septicaemia and meningitis. In addition, listeriosis may cause gastroenteric symptoms in human beings and still births or spontaneous abortions in pregnant women. In the last few years, a number of reported outbreaks and sporadic cases associated with consumption of contaminated meat and meat products with L. monocytogenes have increased in developing countries. A variety of virulence factors play a role in the pathogenicity of L. monocytogenes. This zoonotic pathogen can be diagnosed using both classical microbiological techniques and molecular-based methods. There is limited information about L. monocytogenes recovered from meat and meat products in African countries. This review strives to: (1) provide information on prevalence and control measures of L. monocytogenes along the meat value chain, (2) describe the epidemiology of L. monocytogenes (3) provide an overview of different methods for detection and typing of L. monocytogenes for epidemiological, regulatory and trading purposes and (4) discuss the pathogenicity, virulence traits and antimicrobial resistance profiles of L. monocytogenes.
Mostrar más [+] Menos [-]A review of Listeria monocytogenes from meat and meat products: Epidemiology, virulence factors, antimicrobial resistance and diagnosis Texto completo
2020
Matle, Itumeleng(Agricultural Research Council Bacteriology Division ,University of South Africa Department of Agriculture and Animal Health) | Mbatha, Khanyisile R.(University of South Africa Department of Agriculture and Animal Health) | Madoroba, Evelyn(University of Zululand Department of Biochemistry and Microbiology)
Listeria monocytogenes is a zoonotic food-borne pathogen that is associated with serious public health and economic implications. In animals, L. monocytogenes can be associated with clinical listeriosis, which is characterised by symptoms such as abortion, encephalitis and septicaemia. In human beings, listeriosis symptoms include encephalitis, septicaemia and meningitis. In addition, listeriosis may cause gastroenteric symptoms in human beings and still births or spontaneous abortions in pregnant women. In the last few years, a number of reported outbreaks and sporadic cases associated with consumption of contaminated meat and meat products with L. monocytogenes have increased in developing countries. A variety of virulence factors play a role in the pathogenicity of L. monocytogenes. This zoonotic pathogen can be diagnosed using both classical microbiological techniques and molecular-based methods. There is limited information about L. monocytogenes recovered from meat and meat products in African countries. This review strives to: (1) provide information on prevalence and control measures of L. monocytogenes along the meat value chain, (2) describe the epidemiology of L. monocytogenes (3) provide an overview of different methods for detection and typing of L. monocytogenes for epidemiological, regulatory and trading purposes and (4) discuss the pathogenicity, virulence traits and antimicrobial resistance profiles of L. monocytogenes.
Mostrar más [+] Menos [-]CHLOROQUINE AND HYDROXYCHLOROQUINE ARE AVAILABLE TREATMENT OPTIONS TO FIGHT WITH COVID-19 Texto completo
2020
Shadia S. Alhamd | Manal I. khaleel
The corona virus SARS-CoV-2 caused pandemic Covid-19 disease. At present there is novaccine or drug approved by FDA to treat Covid-19 disease. The high fatality rate and extremefast spreading of disease in the community make researchers to invent possible therapeuticinventions a global priority. Recent studies suggested that Chloroquine (ChQ) andHydroxychloroquine (HChQ) can be used for the treatment of Covid-19 patients. In-vitro testssuggest ChQ and HChQ have good efficiency towards SARS-CoV-2 virus. In this report, wehave reviewed latest literature information about ChQ and HChQ drugs to use for the treatmentof this pandemic.
Mostrar más [+] Menos [-]EVALUATION OF ANTIBACTERIAL OF ZINC OXIDE NANOPARTICLES, ALOE VERA GEL AGAINST MRSA SKIN INJURY Texto completo
2020
Mais E. Ahmed | Ahmed Q Al-Awadi
Microbial resistance to antibiotics increase the risk of infection, so new approach wasinvestigated such as new plant extracts and nano technology, so this study designed to comparethe effects of Zinc oxide nanoparticles and Aloe Vera extraction in treatment of experimentalskin infection with MRSA. In vitro, both were effective against MRSA in well diffusions assay,while in vivo, both were showed antibacterial effects and enhance tissue healing compared withMRSA infective group with priority to Aloe Vera extraction
Mostrar más [+] Menos [-]IMPACT OF AQUEOUS EXTRACT OF ROSEMARY ON TESTICULAR TISSUE IN MALE RATS WITH HYPERTHYROIDISM Texto completo
2020
Fouad Ziedan Hamza | Sumayah Faruq Kasim | Sarah Qahtan M. Salih
The aim of the study to evaluate the enhanced effect of aqueous extract ofrosemary on testis tissue in male rats after inducing hyperthyroidism by L–thyroxin andcompare with propylthiouracil effect. The animals (32 male rats) were divided into twogroups. The first group was a control group consists of 8 male rats that were treated withdistilled water for 12 days and the rest of the animals induced with hyperthyroidism bylevothyroxine 0.5 mg / kg subcutaneously for 12 days. After the induction, the animalswere divided into four groups each consists of eight male rats. The first group was thecontrol group and they were treated with distilled water for another 12 days, the secondgroup included male rats induced hyperthyroidism were treated with distilled water for 12days orally, while the third group included male rats induced hyperthyroidism that weretreated with propylthiouracil at a dose of 10 mg / kg for 12 days orally, and the fourthgroup included male rats induced hyperthyroidism that were treated with rosemary extractat a dose of 12 mg / kg for 10 days, orally. The results showed that rosemary extract led tocomplete healing of testicular tissue, unlike propylthiouracil.
Mostrar más [+] Menos [-]SYNTHESIS AND PHYSIOLOGICAL STUDY OF SCHIFF BASE DERIVED FROM SULFANILAMIDE AND VANILINE Texto completo
2020
Hanadi Abadul Gabar Al-Halfi | Wasfi Aboud Al-Masoudi | Ahlam Ali Alrekabi
The design and production of innovative and safer drugs attracted to organicchemists is urgently required in order to synthesize new compounds with the potentialof biological and chemotherapeutic activities. We're reporting here, the condensationof 4-aminobenzene-1-sulfonamide (sulphanilamide drug) with 4-Hydroxy-3-methoxybenzaldehyde(vanillin), yielded derivative of Schiff base in good yield. Elementalanalysis (CHN), IR, 1H and 13C-NMR spectroscopy were used to characterize thesynthesized compound. Using the Balb/c mouse model, the toxicity of thesynthesized compound was determined. The up and down method of Dixon wasfound to have a body weight of 1677.2 mg / kg LD50 and mild toxicity. The resultsshowed the ability of the prepared compound to improve the TWBC and DWBCvalues approach to control, giving HSV a less harmful effect than the sulfanilamidedrug.
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