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Follicular fluid-derived extracellular vesicles improve in vitro maturation and embryonic development of porcine oocytes
2023
Kang, H.J. | Bang, S.G. | Kim, H.Y. | Han, A.Y. | Miura, S. | Park, H.S. | Saadeldin, I.M. | Lee, S.H. | Cho, J.K.
To optimize the most efficient method for porcine in vitro maturation (IVM), we compared the effects of supplementing extracellular vesicles (EVs) derived from porcine follicular fluid (pFF). The cumulus oocyte complexes were grouped into 4 groups with different supplementations as following: pFF (G1), pFF-depleted EVs (G2), EVs (G3) and control (G4) groups. After IVM with different supplementations, maturation rates and the developmental competences of porcine oocytes and blastocyst development were investigated. Additionally, glutathione (GSH) and reactive oxygen species (ROS) levels were measured in mature oocytes. The EVs were isolated and characterized with cryo-TEM and nanoparticle tracking analysis. The pFF significantly affected the maturation rate, whereas the presence of EVs did not show notable difference in the maturation rates. Although there were numerical increases in the measured parameters in EV and pFF-depleted EVs groups, no significant differences were observed between them. The EV group showed similar oocyte maturation rate for both positive and negative control groups. The GSH was not different among the groups, but ROS levels were significantly lower in pFF-supplemented group when compared with other groups with the highest level in the control group. G2 group wasn’t significantly different G1 and G3 group. G3 group wasn’t significantly different from G2 and G4 group. This suggests that EVs in IVM medium which probably effected partially to protect against oxidative stress and potentially enhance the quality of oocytes. This study indicates that the EVs in pFF play a significant role in improving the efficiency of oocyte maturation in porcine.
Show more [+] Less [-]Spontaneous closure of perimembranous ventricular septal defect in a cat
2023
Park, S.Y. | Jeong, H.S. | Lee, S.G.
We discuss the case of a 5-month-old male British Shorthair cat referred to our hospital following the detection of a heart murmur during a routine vaccination appointment. Two-dimensional echocardiography revealed a 1.18 mm ventricular septal defect (VSD) located immediately below the aortic valve, without signs of secondary cardiac remodeling. Given the absence of cardiac dysfunction, no treatment was administered, and the cat was periodically monitored over the next 2 years. Echocardiography at 29 months of age revealed no signs of the VSD. Future studies are needed to increase the evidence base for spontaneous VSD closure in small animals.
Show more [+] Less [-]Testicular granular cell tumor of two rabbits: case reports
2023
Lee, N.Y. | Lee, J.S. | Yu, B.H. | Kim, J.H. | Kim, D.Y. | Woo, G.H.
Granular cell tumor was described in the testis of two rabbits. Testis from each rabbit was surgically removed and submitted for histopathological diagnosis. Both testes were about 2.0 cm in diameter, firm, and tan. Microscopically, testicular mass consisted of compact sheets of round to polygonal and occasional spindle-shaped cells. The neoplastic cells contain a large amount of eosinophilic granular material in the cytoplasm. The cytoplasmic eosinophilic granules were positive for periodic acid Schiff stain. Immunohistochemically, the neoplastic cells were immunoreactive to Melan-A and vimentin. Based on these results, the testicular mass was diagnosed as a granular cell tumor.
Show more [+] Less [-]Prevalence of bovine trypanosomiasis in Côte d'Ivoire: Systematic review and meta-analysis
2023
Ekra, Jean-Yves(Africa Centre of Excellence for Infectious Diseases of Humans and Animals in East and Southern Africa SACIDS Foundation for One Health ,Sokoine University of Agriculture College of Veterinary Medicine and Biomedical Sciences Department of Microbiology, Parasitology and Biotechnology) | N'Goran, Edouard K.(Université Peleforo Gon Coulibaly Unité de Formation et de Recherche (UFR) des Sciences Biologiques Département de Biochimie- Génétique) | Mboera, Léonard E.G.(Africa Centre of Excellence for Infectious Diseases of Humans and Animals in East and Southern Africa SACIDS Foundation for One Health) | Mafie, Eliakunda M.(Sokoine University of Agriculture College of Veterinary Medicine and Biomedical Sciences Department of Microbiology, Parasitology and Biotechnology)
Bovine trypanosomiasis is a parasitic disease caused by protozoans of the genus Trypanosoma. The disease cause economic losses in livestock production. In order to determine the status of research on this disease in Côte d'Ivoire, we used the systematic review method and meta-analysis. Three electronics databases, namely Google Scholar, PubMed and CrossRef were used to search for publications on trypanosomiasis prevalence that met our inclusion criteria. Twenty five articles were identified, 11 of which met the inclusion criteria. Bovine trypanosomiasis prevalence of 2.99% (95% confidence interval [CI]: 2.96% - 3.01%) to 25.28% (95% CI: 25.17% - 25.38%) were recorded between 1960 and 2021. The analyses showed that the most infected regions were the Bagoue 11.26% (95% CI: 11.25% - 11.27%), Bounkani 14.94% (95% CI: 14.93% - 14.95%), Gbeke 10.34% (95% CI: 10.33% - 10.35%), Marahoue 13.79% (95% CI: 13.78% - 13.80%), Poro 8.50% (95% CI: 8.49% - 8.51%), and Tchologo 11.83% (95% CI: 11.82% - 11.84%).The most sensitive diagnostic method used was the polymerase chain reaction (PCR). The species of trypanosomes diagnosed were Typanosoma vivax 4.99% (95% CI: 4.97% - 5.01%), T. congolense 1.51% (95% CI: 1.49% - 1.52%), and T. brucei 0.61% (95% CI: 0.59% - 0.62%). Despite some variation, the prevalence of bovine trypanosomiasis in Côte d'Ivoire caused mainly by T. vivax has increased in the years between 1977 and 2017. Efforts to control tsetse and other mechanical vectors should also be put in place to minimize its transmission. CONTRIBUTION: The authors studied the prevalence of bovine trypanosomiasis using the systematic review method and MA in order to determine the status of research on this disease in Côte d'Ivoire
Show more [+] Less [-]Description of Culicoides truuskae sp. n. (Diptera: Ceratopogonidae) from southern Africa
2023
Labuschagne, Karien(Agricultural Research Council - Onderstepoort Veterinary Research Faculty of Epidemiology, Parasites and Vectors Department of Entomology,University of Pretoria Faculty of Natural and Agricultural Sciences, Department of Zoology and Entomology) | Meiswinkel, Rudolf | Liebenberg, Danica(North-West University Faculty of Natural and Agricultural Science Unit for Environmental Sciences and Management) | van Zyl, Carissa(North-West University Faculty of Natural and Agricultural Science Unit for Environmental Sciences and Management) | van Schalkwyk, Antoinette(Agricultural Research Council - Onderstepoort Veterinary Research) | Scholtz, Clarke(University of Pretoria Faculty of Natural and Agricultural Sciences, Department of Zoology and Entomology)
Culicoides truuskae Labuschagne and Meiswinkel sp. n. is described and illustrated in both sexes from material collected in South Africa and Namibia. It is restricted to the xeric western margin of the subcontinent, occurring in Fynbos, Nama-Karoo and Succulent Karoo ecoregions in South Africa and Desert and Savanna ecoregions in Namibia experiencing < 600 mm of rainfall annually. Culicoides truuskae sp. n. is part of the Afrotropical 'plain-wing' Culicoides in which the wing lacks a distinguishing pattern of light and dark spots; the diagnostic dark smudge that traverses wing cell r3 may result in C. truuskae sp. n. being misidentified as the sympatric but phyletically unrelated Culicoides herero (Enderlein) - (of the Similis group, subgenus Oecacta Poey). Additionally, this study is the first description of the male of C. herero. C. truuskae sp. n. and Culicoides coarctatus Clastrier and Wirth share similar characters in the male genitalia, although the two species are separable on wing pattern and female flagellum sensilla coeloconica (SCo) distribution. The breeding habitat and adult female blood-feeding preferences of C. truuskae sp. n. are not known. A maximum likelihood phylogenetic tree, using mitochondrial cytochrome c oxidase I (COI) sequence data, is provided to further clarify the relationship between C. truuskae sp. n., C. coarctatus and C. herero. Extensive light trap data, collected over 30 years, are used to map the distribution ranges of C. truuskae sp. n., C. coarctatus and C. herero in Southern Africa. CONTRIBUTION: The description of this new species and the description of the male of C. herero increases our understanding of the diversity and distribution of Culicoides species in southern Africa.
Show more [+] Less [-]Monitoring the genetic variation of some Escherichia coli strains in wild birds and cattle
2023
Ibrahim, Ghada A.(Animal Health Research Institute Agriculture Research Center Bacteriology Department) | Salah-Eldein, Ahmed M.(Suez Canal University Faculty of Veterinary Medicine Wildlife and Zoo Department) | Al-zaban, Mayasar l.(Princess Nourah bint Abdulrahman University College of Science Department of Biology) | El-Oksh, Amal S.A.(Animal Health Research Institute Agriculture Research Center Biotechnology Department, Reference Lab of Quality Control of Poultry Production) | Ahmed, Elsayyad M.(Agricultural Research Center Animal Health, Research Institute Department of Virology) | Farid, Doaa S.(Arish University Faculty of Environmental Agricultural Sciences Department of Environmental Protection) | Saad, Enas M.(Suez Canal University Faculty of Veterinary Medicine Wildlife and Zoo Department)
To date, there is limited data about the genetic relationship of Escherichia coli between wild birds and cattle because these birds act as silent vectors for many zoonotic bacteria. This study aimed to elucidate the role of rooming wild birds in the vicinity of cattle farm in transmission of the same pathogenic E. coli variants, identifying their virulence, resistance traits and genetic similarities of fimH virulence gene. About 240 faecal/cloacal swabs were collected from both species and examined bacteriologically. Escherichia coli was yielded in 45.8% and 32.5%, respectively, of examined cattle and wild birds. The most prevalent detected E. coli serovar was O26. High tetracycline and chloramphenicol resistance were recorded; however, gentamycin and ciprofloxacin exhibited the highest sensitivity rates. Polymerase chain reaction (PCR) conserved genotypic resistance (tetA and blaCTX-M) and virulence attributes (fimH, stx1, eaeA and ompA) of E. coli isolates were discussed in detail. The fimH gene revealed 100% sequence similarity when comparing with different E. coli isolates globally and locally. Finally, a close genetic association of E. coli with both wild birds and cattle was detected, thus strengthening its role in the dissemination of the infection via environment. Prevention and conservative policy should be carried as E. coli constitute enormous significant zoonotic risks to livestock and animal workers. Also, further studies to the whole genome sequencing of fimH, other virulence and resistance genes of E. coli are recommended trying to limit the possibilities of co-infection and transfer among different species. CONTRIBUTION: The current study recorded updated data about the critical infectious role of wild birds to livestock, including cattle farms in Egypt. It also delivered some recommendations for good hygienic practices in cattle farms which must be implemented for handling animal manure.
Show more [+] Less [-]Characterisation of South African field Ehrlichia ruminantium using multilocus sequence typing
2023
Dlamkile, Zinathi(University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases) | Neves, Luis(University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases,Eduardo Mondlane University Centro de Biotecnologia) | Morar-Leather, Darshana(University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases) | Brandt, Christopher(Agricultural Research Council Onderstepoort Veterinary Research Institute Department of Vaccines and Diagnostics Development) | Pretorius, Alri(University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases,Agricultural Research Council Onderstepoort Veterinary Research Institute Department of Vaccines and Diagnostics Development) | Steyn, Helena(Agricultural Research Council Onderstepoort Veterinary Research Institute Department of Vaccines and Diagnostics Development) | Liebenberg, Junita(Agricultural Research Council Onderstepoort Veterinary Research Institute Department of Vaccines and Diagnostics Development)
Heartwater, one of the major tick-borne diseases of some domestic and wild ruminants in Africa, is caused by Ehrlichia ruminantium. The genetic diversity of E. ruminantium isolates renders the available vaccine ineffective against certain virulent isolates. To better understand the E. ruminantium genotypes in South Africa, a total of 1004 Amblyomma hebraeum tick deoxyribonucleic acid (DNA) samples from cattle in three South African provinces were tested by pCS20 Sol1 real-time polymerase chain reaction (qPCR) and characterised by multilocus sequence typing (MLST) using five housekeeping genes. Out of 1004 samples tested, 222 (22%) were positive for E. ruminantium. The occurrence of E. ruminantium in Mpumalanga, KwaZulu-Natal and Limpopo provinces was 19%, 22% and 27%, respectively. The E. ruminantium positive samples were screened for housekeeping genes and sequenced. Phylogenetic analysis revealed three main lineages: clade 1 made up of worldwide isolates (eastern, southern Africa, and Caribbean isolates), clade 2 comprised only West African isolates and clade 3 consisted of Omatjenne, Kümm2 and Riverside. Some study sample sequences were not identical to any of the reference isolates. However, they could all be grouped into the worldwide clade. Genetic variation in the sequenced regions was observed in the form of single nucleotide polymorphisms (SNPs). Using MLST to characterise E. ruminantium field isolates allowed the South African genotypes to be clearly distinguished from the distinct West African isolates. CONTRIBUTION: Characterisation of E. ruminantium field isolates is important for the control of heartwater and contributes to preliminary knowledge required for the development of a more practical vaccine against heartwater.
Show more [+] Less [-]Approaches to increase recovery of bacterial and fungal abortion agents in domestic ruminants
2023
Jonker, Annelize(University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases) | Thompson, Peter N.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies) | Michel, Anita L.(University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases)
Abortions in domestic ruminants cause significant economic losses to farmers. Determining the cause of an abortion is important for control efforts, but it can be challenging. All available diagnostic methods in the bacteriology laboratory should be employed in every case due to the many limiting factors (autolysis, lack of history, range of samples) that complicate the investigation process. The purpose of this study was to determine whether the recovery of diagnostically significant isolates from domestic ruminant abortion cases could be increased through the use of a combination of the existing aerobic culture and Brucella selective method with methods that are commonly recommended in the literature reporting abortion investigations. These methods are examination of wet preparations and impression smears stained by the modified Ziehl-Neelsen method, anaerobic, microaerophilic, Leptospira, Mycoplasma and fungal culture. Samples of placenta and aborted foetuses from 135 routine clinical abortion cases of cattle (n = 88), sheep (n = 25) and goats (n = 22) were analysed by the new combination of methods. In 46 cases, bacteria were identified as aetiological agents and in one case a fungus. Isolation of Brucella species increased to 7.4% over two years compared with the previous 10 years (7.3%), as well as Campylobacter jejuni (n = 2) and Rhizopus species (n = 1). Salmonella species (5.9%) and Trueperella pyogenes (4.4%) were also isolated more often. In conclusion, the approach was effective in removing test selection bias in the bacteriology laboratory. The importance of performing an in-depth study on the products of abortion by means of an extensive, combination of conventional culture methods was emphasised by increased isolation of Brucella abortus and isolation of C. jejuni. The combination of methods that yielded the most clinically relevant isolates was aerobic, microaerophilic, Brucella and fungal cultures.
Show more [+] Less [-]Th1 and Th2 epitopes of Cowdria polymorphic gene 1 of Ehrlichia ruminantium
2023
Ngoepe, Tlou A.(Agricultural Research Council-Onderstepoort Veterinary Research Department of Immunology ,University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases,University of Pretoria Faculty of Health Sciences Department of Immunology) | Pretorius, Alri(Agricultural Research Council-Onderstepoort Veterinary Research Department of Immunology ,University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases) | Steyn, Helena C.(Agricultural Research Council-Onderstepoort Veterinary Research Department of Immunology) | van Kleef, Mirinda(Agricultural Research Council-Onderstepoort Veterinary Research Department of Immunology ,University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases)
Cowdria polymorphic gene 1 (cpg1, Erum2510, ERUM_RS01380) has been shown to induce 30% and 100% protection in sheep immunised by deoxyribonucleic acid (DNA) prime combined with DNA boost and DNA prime combined with protein boost, respectively, against heartwater infection via needle challenge. To localise its antigenic regions for inclusion in a multi-epitope DNA vaccine against heartwater, Erum2510 was cleaved into five overlapping subfragments. These subfragments were expressed individually in an Escherichia coli host expression system and evaluated for their ability to induce proliferative responses, Th1 and Th2 cytokines (interferon gamma [IFN-γ] and interleukin 4 [IL-4]) via enzyme-linked immunospot (ELISpot), quantitative real time polymerase chain reaction (qRT-PCR) and flow cytometry. Recombinant (r)proteins 3 and 4 were shown to induce immunodominant Th1 and Th2 immune responses characterised by the secretion of effector cytokines IFN-γ and IL-4 in addition to differential messenger ribonucleic acid (mRNA) expression of tumour necrosis factor (TNF), IL-2, IL-1, IL-18, IL-10, transforming growth factor (TGF), granulocyte-macrophage colony-stimulating factor (GM-CSF) and inducible nitric oxide synthase (iNOS). Thirty-seven overlapping synthetic peptides (16 mer) spanning the lengths of these immunodominant rproteins were synthesised and assayed. A peptide pool comprising p9 and p10 derived from rprotein 3 induced a Th1-biased immune response. A peptide pool comprising p28 and p29 derived from rprotein 4 induced a mixed Th1 and Th2 immune response characterised by secretion of IFN-γ and differential mRNA expression of IL-1, IL-2, IL-10, IL-12, iNOS, TGF, TNF and GM-CSF. Only one of the peptides (p29) induced secretion of IL-4. Phenotypic analysis showed significant activation of cluster of differentiation 8+ (CD8+), cluster of differentiation 4+ (CD4+) and B+ lymphocyte populations. Findings suggest that Erum2510 rproteins and synthetic peptides can induce both cellular and humoral immune responses, thereby implicating their importance in protection against heartwater. CONTRIBUTION: This study will facilitate the design of an effective multi-epitope DNA vaccine against heartwater that will contribute to control this economically important disease in sub-Saharan Africa and beyond.
Show more [+] Less [-]Seroprevalence and factors associated with Coxiella burnetii exposure in goats in Moretele
2023
Magadu, Rungano(University of Pretoria Faculty of Veterinary Science) | Thompson, Peter N.(University of Pretoria Faculty of Veterinary Science)
Infection with Coxiella burnetii causes significant economic impact and poses zoonotic risk to people exposed to livestock, yet few studies in South Africa have assessed seroprevalence of C. burnetii infection and no information is available for goats. Very little information is available regarding risk factors and outcomes of C. burnetii infection in peri-urban farming areas where widespread mixing of ruminants occurs. This study estimated the seroprevalence of C. burnetii infection among communally farmed goats in an area adjacent to the densely populated Gauteng province. Sera were collected from 216 goats in 39 herds, and questionnaires were completed to establish management practices as potential risk factors. C. burnetii antibody testing was done by ELISA. Thirty two out of 216 goats tested positive for C. burnetii antibodies and the overall seroprevalence, adjusted for sampling weights and clustering, was 18.4% (95% confidence interval [CI]: 12.2% - 23.5%). The intraclass correlation coefficient was 0.06, indicating low-to-moderate clustering. Multiple logistic regression showed age was significantly associated with seropositivity, with higher seroprevalence in animals ≥ 19 months old (26%) than animals ≤ 6 months old (6%) (odds ratio [OR]: 6.6; p = 0.010). We concluded C. burnetii infection is common in goats in Moretele and a potential cause of abortion in goats and poses the potential zoonotic disease risk. CONTRIBUTION: Despite the threats posed on animal health and productivity, scant information is published on C. burnetii in South Africa. This research established preliminary estimates of C. burnetii seroprevalence. The research is original from a South African perspective, relevant to Africa and focused on infectious disease in livestock.
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