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Serosurvey of peste des petits ruminants virus in small ruminants from different agro-ecological zones of Nigeria
2016
Woma, Timothy Y.(University of Pretoria Department of Veterinary Tropical Diseases ,National Veterinary Research Institute Morbilliviruses Research Laboratory) | Ekong, Pius S.(National Veterinary Research Institute Morbilliviruses Research Laboratory) | Bwala, Dauda G.(National Veterinary Research Institute Morbilliviruses Research Laboratory) | Ibu, John O.(National Veterinary Research Institute Morbilliviruses Research Laboratory) | Ta'ama, Louisa(National Veterinary Research Institute Morbilliviruses Research Laboratory) | Dyek, Dyek Y.(National Veterinary Research Institute Morbilliviruses Research Laboratory) | Saleh, Ladi(National Veterinary Research Institute Morbilliviruses Research Laboratory) | Shamaki, David(National Veterinary Research Institute Morbilliviruses Research Laboratory) | Kalla, Demo J.U.(Abubakar Tafawa Balewa University) | Bailey, Dalan(University of Birmingham School of Immunity and Infection) | Kazeem, Haruna M.(Ahmadu Bello University Zaria Department of Veterinary Microbiology) | Quan, Melvyn(University of Pretoria Department of Veterinary Tropical Diseases)
Peste des petits ruminants, caused by the peste des petits ruminants virus (PPRV), is a highly contagious and economically important transboundary viral disease of domestic and wild small ruminants and a major hindrance to small-ruminant production in Nigeria. The seroprevalence and distribution of PPRV antibodies in small ruminants in rural households, farms, live animal markets and slaughter slabs across the six different agro-ecological zones of Nigeria were determined. A total of 4548 serum samples from 3489 goats and 1059 sheep were collected in 12 states. A PPRV competitive enzyme-linked immunosorbent assay was used to test the samples and the data analysed with R statistical software version 3.0.1. The study animals included all ages and both sexes. The overall prevalence estimate of sera positive for PPRV antibodies was 23.16% (n = 1018 positive samples per 4548 total samples, 95% confidence interval: 21.79% - 24.57%). There were significant differences in the seroprevalence between the states (p = 0.001). Taraba State had the highest seroprevalence of 29.51%, whilst the lowest seroprevalence of 14.52% was observed in Cross River State. There were no significant differences in the PPRV seroprevalence between male and female animals (p = 0.571), age (p = 0.323) and between species (p = 0.639). These data indicate the current seroprevalence to PPRV in the small-ruminant population in Nigeria.
اظهر المزيد [+] اقل [-]Contagious bovine pleuropneumonia: Seroprevalence and risk factors in Western Oromia, Ethiopia
2016
Daniel, Garuma(Jimma University School of Veterinary Medicine) | Abdurahaman, Mukarim(Jimma University School of Veterinary Medicine) | Tuli, Getachew(National Animal Health Diagnostic and Investigation Center) | Deresa, Benti(Jimma University School of Veterinary Medicine)
Contagious bovine pleuropneumonia (CBPP) is one of the most important threats to cattle health and production in Ethiopia. At the livestock farm of the Bako Agricultural Research Center, an outbreak of respiratory disease of cattle occurred in May 2011, and many animals were affected and died before the disease was diagnosed. Therefore, this study was designed to determine the seroprevalence of CBPP antibodies in selected districts of Western Oromia Region and to assess the potential risk factors for the occurrence of the disease. A cross-sectional study was conducted from November 2013 to March 2014 in three selected districts of Western Oromia Region. A total of 386 sera were examined for the presence of specific antibodies against Mycoplasma mycoidesmycoides small colony (MmmSC), using a competitive enzyme-linked immunosorbent assay. The risk factors that were evaluated in this study were geographical location, age, sex, breed and body condition. The overall seroprevalence in this study was 28.5%. The seroprevalence of Mycoplasma mycoidesmycoides small colony antibodies at the district level was 40.3%, 19.0% and 5.7% in Gobbu Sayyo, BakoTibbe and Horro districts, respectively. There was a statistically significant variation (p < 0.05) in the prevalence of antibodies amongst the districts. However, animal-related risk factors, such as age, sex, breed and body condition, were not significantly associated (p > 0.05) with the serological status of the animal. This study showed that the overall prevalence of CBPP in Western Oromia Zones was high. This warrants the implementation of appropriate preventive and control measures to minimise the economic losses associated with the disease.
اظهر المزيد [+] اقل [-]Cryptosporidium genotypes in children and calves living at the wildlife or livestock interface of the Kruger National Park, South Africa
2016
Samra, Nada Abu(University of Pretoria Department of Production Animal Studies) | Jori, Ferran(French Research Institute for Agricultural Development ,Botswana College of Agriculture Department of Animal Science and Production) | Cacciò, Simone M.(Istituto Superiore di Sanita Department of Infectious, Parasitic and Immunomediated Diseases) | Frean, John(National Institute for Communicable Diseases Centre for Opportunistic, Tropical and Hospital Infections ,University of the Witwatersrand Research Institute for Malaria) | Poonsamy, Bhavani(National Institute for Communicable Diseases Centre for Opportunistic, Tropical and Hospital Infections) | Thompson, Peter N.(University of Pretoria Department of Production Animal Studies)
Cryptosporidium infection is one of the most common causes of parasitic diarrhoea worldwide in cattle and humans. In developing countries, human cryptosporidiosis is most prevalent during early childhood and links between zoonotic infection and animal related activities have been demonstrated. This study investigated the prevalence and species/genotype distribution of Cryptosporidium among children (< 5 years) and calves (< 6 months) living in a rural farming area adjacent to the Kruger National Park in South Africa, where interactions between humans and wild and domestic animals are known to occur. Cryptosporidium oocysts were detected in 8/143 stool samples of children recruited within the hospital system (5.6%; 95% CI 2.4%, 10.7%) and in 2/352 faecal samples of calves (0.6%; 95% CI 0.1%, 2.0%) using the modified Ziehl-Neelsen (MZN) staining technique. Microscopy positive samples from children were further analysed by PCR targeting the 18S rRNA gene and identified as Cryptosporidium hominis (3/4) and Cryptosporidium meleagridis (1/4). Regardless of the microscopy outcome, randomly selected samples (n = 36) from calves 0-4 months of age were amplified and sequenced at the 18S rRNA gene using nested PCR. Two calves tested positive (5.6%; 95% CI 1.7%, 18.7%), and revealed the presence of Cryptosporidium parvum and Cryptosporidium bovis. The detection of only two zoonotic species (C. parvum in one calf and C. meleagridis in one child) suggests that zoonotic cryptosporidiosis is not currently widespread in our study area; however, the potential exists for amplification of transmission in an immunocompromised population.
اظهر المزيد [+] اقل [-]Prevalence of Theileria and Babesia species in Tunisian sheep
2016
Rjeibi, Mohamed R.(Manouba University National School of Veterinary Medicine Laboratory of Parasitology,Carthage University Department of Biology) | Darghouth, Mohamed A.(Manouba University National School of Veterinary Medicine Laboratory of Parasitology) | Gharbi, Mohamed(Manouba University National School of Veterinary Medicine Laboratory of Parasitology)
In this study, the prevalence of Theileria and Babesia species in sheep was assessed with Giemsa-stained blood smear examination and polymerase chain reaction to identify the different piroplasms in 270 sheep from three Tunisian bioclimatic zones (north, centre, and south). The overall infection prevalence by Babesia spp. and Theileria spp. in Giemsa-stained blood smears was 2.9% (8 / 270) and 4.8% (13/270) respectively. The molecular results showed that sheep were more often infected by Theileria ovis than Babesia ovis with an overall prevalence of 16.3% (44/270) and 7.8% (21/270) respectively (p = 0.01). The molecular prevalence by Babesia ovis was significantly higher in females than in males (p < 0.05). According to localities B. ovis was found exclusively in sheep from the centre of Tunisia (Kairouan) whereas Theileria ovis was found in all regions. Infections with T. ovis and B. ovis were confirmed by sequencing. The sequence of T. ovis in this study (accession numbers KM924442) falls into the same clade as T. ovis deposited in GenBank. The T. ovis amplicons (KM924442) showed 99%-100% identities with GenBank sequences. Moreover, comparison of the partial sequences of 18S rRNA gene of B. ovis described in this study (KP670199) revealed 99.4% similarity with B. ovis recently reported in northern Tunisia from sheep and goats. Three nucleotides were different at positions 73 (A/T), 417 (A/T), and 420 (G/T). It also had 99% identity with B. ovis from Spain, Turkey and Iraq. The results suggest a high T. ovis prevalence in Tunisia with a decreasing north-south gradient. This could be correlated to the vector tick distribution.
اظهر المزيد [+] اقل [-]An acetone extract of Clausena anisata may be a potential control agent for flies encountered in cutaneous myiasis
2016
Mukandiwa, Lillian(University of Pretoria Department of Paraclinical Sciences) | Eloff, Jacobus N.(University of Pretoria Department of Paraclinical Sciences) | Sibanda, Donald R.(Mpumalanga Veterinary Services,) | Naidoo, Vinny(University of Pretoria Department of Paraclinical Sciences)
Clausena anisata is a medicinal plant used traditionally to treat myiasis and as an insect repellent by various communities. We have previously demonstrated the effects of C. anisata extracts on blowfly feeding and development in our laboratory. The impact of C. anisata leaf extracts on populations of different fly species on farms in Mpumalanga, South Africa was investigated in this study under field conditions. Flies were exposed to liver baits treated with acetone leaf extracts of C. anisata (150 mg/mL). Fly numbers and composition on two farms, with and without C. anisata treated liver, were compared during a period of 12 weeks when fly populations were expected to be high. Observations were made on fly behaviour and development, adult sizes and numbers. The flies exposed to liver treated with the leaf extract of C. anisata had a decreased rate of development, prolonged larval period, smaller body sizes and more sluggish behaviour compared to those subjected to the control treatment. No significant differences were, however, found between the numbers and sizes of flies on the treated and on the control farm, which was most likely due to the limited nature of the baiting programme we followed. The effects of C. anisata extracts on blowfly behaviour and development observed in previous laboratory studies were confirmed in this field evaluation. Although the extracts did not have a significant effect on the overall population size in this experiment, we believe that the C. anisata leaf extract could be useful in integrated pest management based on its effect on larval development. In addition, species such as Lucilia cuprina and Chrysomya marginalis seemed to have been repelled by the C. anisata treated liver; as a result, further work should explore this aspect and how it can be used for the protection of animals.
اظهر المزيد [+] اقل [-]Prevalence of virulence and antimicrobial resistance genes in Salmonella spp. isolated from commercial chickens and human clinical isolates from South Africa and Brazil
2016
Zishiri, Oliver T.(University of KwaZulu-Natal Department of Genetics) | Mkhize, Nelisiwe(University of KwaZulu-Natal Department of Genetics) | Mukaratirwa, Samson(University of KwaZulu-Natal Department of Genetics)
Salmonellosis is a significant public health concern around the world. The injudicious use of antimicrobial agents in poultry production for treatment, growth promotion and prophylaxis has resulted in the emergence of drug-resistant strains of Salmonella. The current study was conducted to investigate the prevalence of virulence and antimicrobial resistance genes from Salmonella isolated from South African and Brazilian broiler chickens as well as human clinical isolates. Out of a total of 200 chicken samples that were collected from South Africa 102 (51%) tested positive for Salmonella using the InvA gene. Of the overall 146 Salmonella-positive samples that were screened for the iroB gene, most of them were confirmed to be Salmonella enterica with high prevalence rates. All the Salmonella isolates obtained were subjected to antimicrobial susceptibility testing with ten antibiotics. Salmonella isolates from South African chickens exhibited resistance to almost all antimicrobial agents used. All the samples were further subjected to the Polymerase Chain Reaction in order to screen some common antimicrobial and virulence genes of interest, namely spiC, pipD, misL, orfL, pse-1, tet A, tet B, ant (3")-la, sul 1 and sul. All the Salmonella-positive isolates exhibited resistance to at least one antimicrobial agent; however, antimicrobial resistance patterns demonstrated that multiple drug resistance was prevalent. The findings provide evidence that broiler chickens are colonised by pathogenic Salmonella harbouring antimicrobial resistance genes. Therefore, it is evident that there is a need for prudent use of antimicrobial agents in poultry production systems in order to mitigate the proliferation of multiple drug resistance across species.
اظهر المزيد [+] اقل [-]Prevalence, distribution and pattern of gastric lesions in slaughtered pigs in south-western Nigeria
2016
Omotosho, Oladipo O.(University of Ibadan Department of Veterinary Medicine) | Emikpe, Benjamin O.(University of Ibadan Department of Veterinary Pathology) | Lasisi, Olalekan T.(University of Ibadan Department of Veterinary Medicine) | Jarikre, Theophilus A.(University of Ibadan Department of Veterinary Pathology)
Gastric lesions, especially ulceration, cause significant economic losses in the swine industry worldwide. The study was designed to assess its prevalence, distribution and pattern in pigs in south-western Nigeria. Slaughter house surveys were conducted on three government-established abattoirs in Lagos, Ogun and Oyo states. Stomachs from 480 pigs were assessed for gross lesions, which were graded using a modification of a standard technique. Tissues from different regions of the stomach were routinely stained to assess histopathologic changes. Data were presented as frequency counts and analysed using analysis of variance and chi-square technique. Significance was determined at p ≤ 0.05. Gastric lesions were encountered across the four regions of the stomach with a point prevalence of 57.29%. The prevalence of lesions in the non-glandular region was 32.9%, with severe hyperkeratosis (13.13%) being most frequently observed (p < 0.05). Erosions were significantly higher in the cardia (8.54%) (p < 0.05), followed by fundus (8.33%). Gastric ulcers were significantly higher in the fundus (19.58%) (p < 0.05). Scars of healed ulcers and lacerations were also observed in the fundus (5.42%) (p < 0.05). The gastric lesion distribution across the four regions of the stomach and the occurrence of ulceration in the fundus showed an unusual pattern, which is rarely reported in other parts of the world. The reason for these findings in pigs in Nigeria is not fully understood; therefore, further studies are required to identify and manage these factors for increased productivity, improved animal welfare and enhanced food security.
اظهر المزيد [+] اقل [-]Feline panleukopaenia virus in captive non-domestic felids in South Africa
2016
Lane, Emily P.(National Zoological Gardens of South Africa Department of Research and Scientific Services) | Brettschneider, Helene(National Zoological Gardens of South Africa Department of Research and Scientific Services) | Caldwell, Peter(Old Chapel Veterinary Clinic) | Oosthuizen, Almero(National Zoological Gardens of South Africa Department of Research and Scientific Services) | Dalton, Desiré L.(National Zoological Gardens of South Africa Department of Research and Scientific Services ,University of the Free State Department of Genetics) | du Plessis, Liza(IDEXX Laboratories (Pty) Ltd.) | Steyl, Johan(University of Pretoria Department of Paraclinical Science) | Kotze, Antoinette(National Zoological Gardens of South Africa Department of Research and Scientific Services ,University of the Free State Department of Genetics)
An outbreak of feline panleukopaenia virus (FPLV) infection was diagnosed by pathology, electron microscopy and polymerase chain reaction (PCR) in vaccinated captive-bred subadult cheetahs in South Africa. Subsequent to this disease outbreak, 12 cases of FPLV diagnosed on histology were confirmed by PCR in captive African black-footed cat, caracal, cheetah, lion, ocelot and serval. Phylogenetic analyses of the viral capsid protein gene on PCR-positive samples, vaccine and National Center for Biotechnology Information (NCBI) reference strains identified a previously unknown strain of FPLV, present since at least 2006, that differs from both the inactivated and the modified live vaccine strains. A previously described South African strain from domestic cats and cheetahs was identified in a serval. Surveys of FPLV strains in South African felids are needed to determine the geographical and host species distribution of this virus. Since non-domestic species may be reservoirs of parvoviruses, and since these viruses readily change host specificity, the risks of FPLV transmission between captive-bred and free-ranging carnivores and domestic cats and dogs warrant further research.
اظهر المزيد [+] اقل [-]Comparative performance of traps in catching tsetse flies (Diptera: Glossinidae) in Tanzania
2016
Malele, Imna I.(Vector & Vector Borne Disease Institute) | Ouma, Johnson O.(Kenya Agricultural and Livestock Research Organization Biotechnology Research Institute ,Vector Health International Africa Technical Research Centre) | Nyingilili, Hamisi S.(Vector & Vector Borne Disease Institute) | Kitwika, Winston A.(Vector & Vector-Borne Diseases Centre) | Malulu, Deusdedit J.(Vector & Vector Borne Disease Institute) | Magwisha, Henry B.(Tanzania Veterinary Laboratory Agency) | Kweka, Eliningaya J.(Tropical Pesticides Research Institute Division of Livestock and Human Diseases Vector Control ,Catholic University of Health and Allied Sciences Department of Medical Parasitology and Entomology)
This study was conducted to determine the efficiency of different tsetse traps in 28 sites across Tanzania. The traps used were biconical, H, NGU, NZI, pyramidal, S3, mobile, and sticky panels. Stationary traps were deployed at a distance of 200 m apart and examined 72 h after deployment. The results showed that 117 (52.2%) out of the 224 traps deployed captured at least one Glossina species. A total of five Glossina species were captured, namelyGlossina brevipalpis, Glossina pallidipes, Glossina swynnertoni, Glossina morsitans, and Glossina fuscipes martinii. Biconical traps caught tsetse flies in 27 sites, pyramidal in 26, sticky panel in 20, mobile in 19, S3 in 15, NGU in 7, H in 2 and NZI in 1. A total of 21 107 tsetse flies were trapped, with the most abundant species being G. swynnertoni (55.9%), followed by G. pallidipes (31.1%), G. fuscipes martinii (6.9%) and G. morsitans (6.0%). The least caught was G. brevipalpis (0.2%). The highest number of flies were caught by NGU traps (32.5%), followed by sticky panel (16%), mobile (15.4%), pyramidal (13.0%), biconical (11.3%) and S3 (10.2%). NZI traps managed to catch 0.9% of the total flies and H traps 0.7%. From this study, it can be concluded that the most efficient trap was NGU, followed by sticky panel and mobile, in that order. Therefore, for tsetse fly control programmes, NGU traps could be the better choice. Conversely, of the stationary traps, pyramidal and biconical traps captured tsetse flies in the majority of sites, covering all three ecosystems better than any other traps; therefore, they would be suitable for scouting for tsetse infestation in any given area, thus sparing the costs of making traps for each specific Glossina species.
اظهر المزيد [+] اقل [-]Enhanced expression of recombinant beta toxin of Clostridium perfringens type B using a commercially available Escherichia coli strain
2016
Bakhshi, Fatemeh(Islamic Azad University Department of Biology) | Langroudi, Reza Pilehchian(Education and Extension Organization Razi Vaccine and Serum Research Institute) | Eimani, Bahram Golestani(Islamic Azad University Department of Biology)
Clostridium perfringens beta toxin is only produced by types B and C and plays an important role in many human and animal diseases, causing fatal conditions that originate in the intestines. We compared the expression of C. perfringens type B vaccine strain recombinant beta toxin gene in theEscherichia coli strains RosettaTM(DE3) and BL21(DE3). The beta toxin gene was extracted from pJETβ and ligated with pET22b(+). pET22β was transformed into E. coli strains BL21(DE3) and RosettaTM(DE3). Recombinant protein was expressed as a soluble protein after isopropyl β-D-1-thiogalactopyranoside (IPTG) induction in strain RosettaTM(DE3) but not in BL21(DE3). Expression was optimised by growing recombinant cells at 37 °C and at an induction of 0.5 mM, 1 mM, 1.5 mM IPTG. Expression was evaluated using sodium dodecyl sulfate Polyacrylamide gel electrophoresis (SDS-PAGE). The recombinant protein was purified via Ni-NTA and was analysed using western blot. We concluded that E. coli strain RosettaTM(DE3) can enhance the expression of C. perfringens recombinant beta toxin.
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