Faculty Day Posters

Permanent URI for this collectionhttp://hdl.handle.net/2263/56064

A collection of posters presented at The Faculty of Veterinary Science of the University of Pretoria on Faculty Day which is held each year in spring at the Onderstepoort Campus. The posters are showcasing the research activities of staff and students at the Faculty.

Available posters

2015	2016	2017

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Now showing 1 - 20 of 28

Mycobacterium bovis infection in cattle at the wildlife/livestock interface in northern KwaZulu-Natal province, South Africa
(Pretoria : University of Pretoria, Faculty of Veterinary Science, 2017-09-07) Sichewo, P.R.; Etter, Eric Marcel Charles; Michel, Anita Luise; University of Pretoria. Faculty of Veterinary Science. Dept. of Veterinary Tropical Diseases; University of Pretoria. Faculty of Veterinary Science. Dept. of Production Animal Studies
A cross-sectional study was carried out in Northern KwaZulu-Natal at the wildlife/livestock interface to determine the prevalence of Mycobacterium bovis infection in cattle using a modified BOVIGAM® interferon gamma assay (IFN-γ). Although cattle are known as the primary host, M. bovis can also affect other domestic animals, wildlife and humans. Using a random sampling technique, whole blood samples were collected from 387 cattle registered at two dip tanks (Mpempe and Nkomo) in the uMkhanyakude district, which consisted of 267 females and 120 males from a total of 100 herds. The apparent M. bovis prevalence rate at animal level was 13.9% (95% confidence interval (CI) 10.6 - 17.4) and the true prevalence indicated a similar prevalence rate of 13.6% (95% CI 10.2 - 16.9). The apparent and true prevalence rate at Nkomo dip tank was 7.9% (95% CI 4.4 - 13.6) and 5.7% (95% CI 1.4 - 11.6) respectively. The apparent and true prevalence rates at Mpempe dip tank were almost similar: 17.3% (95% CI 13.1 - 22.5) and 18% (95% CI 11.9 - 24.1) respectively. At Mpepe dip tank 20/52 (39%) of the farmers had at least one test positive animal, whilst at Nkomo dip tank, this figure was 8/48 (17%). Based on sex, 11 (9.1%, 95% CI 3.9 - 14.2) of the males and 43 (16.1%, 95% CI 11.7 - 20.5) of the females tested positive with the assay. This study forms part of a One Health project at the wildlife/livestock interface. Confirmation of infection will be done through isolation and culture of tissues from test positive animals. The isolates will be genotyped and compared with isolates from wildlife, to monitor M. bovis transmission at the wildlife/livestock interface.
Carnivore population dynamics on two reserves, comparable or not?
(Pretoria : University of Pretoria, Faculty of Veterinary Science, 2017-09-07) Wentzel, Jeanette Maria; Camacho, Gerrie C.; Bourn, M.; Fosgate, Geoffrey Theodore; University of Pretoria. Faculty of Veterinary Science. Dept. of Production Animal Studies; Mpumalanga Tourism and Parks Agency; Mpumalanga Tourism and Parks Agency. Manyeleti Nature Reserve; University of Pretoria. Faculty of Veterinary Science. Hans Hoheisen Research Station
Small carnivore species might provide the disease link in disease transmission between domestic dogs and apex predators. The objective of this study was to determine the presence of carnivores and prey species on two wildlife reserves in Mpumalanga Province. Carnivore presence was determined on two reserves managed by Mpumalanga Tourist and Parks Agency(MTPA). Manyeleti is contiguous with Kruger National Park (KNP), 23 000 hectares in area, and has villages on one side. Andover is not adjacent to KNP, 7 000 hectares in area, and has villages on three sides of the reserve. The presence of carnivores and determination of inter-species interactions were measured during a two-year period using randomly placed clusters of camera traps. These camera traps were placed at each selected location for a period of 4 to 6 weeks before being moved. Permanent camera traps were also placed on the interface between reserves and villages. Data were entered into Microsoft Excel and mapped using ArcGIS 10.4.1. Ordinary Kriging and inverse distance weighting interpolation were used to determine the spatial distributions of observed wildlife. The Mackenzie model was used to determine the daily detection probability of each species. The most abundant species present in Manyeleti were hyena (Crocuta crocuta) and Lion (Panthera leo). In Andover, the only apex predator present was leopard (Panthera pardus), while serval (Leptailurus serval), caracal (Felis caracal), and mongoose (Mungos mungo) were also present. Some locations were shared among carnivore species, while other areas had no carnivore species detected at all. Areas with prey species, water and access routes to water had the highest probability of carnivore detection.
Herd-level prevalence of bovine leukaemia virus infection and associated risk factors in commercial dairies in five provinces of South Africa
(Pretoria : University of Pretoria, Faculty of Veterinary Science, 2017-09-07) Maboe, Sello J.; Gratwick, W.; Thompson, P.N. (Peter N.); University of Pretoria. Faculty of Veterinary Science. Dept. of Production Animal Studies
The immunosuppressive nature of bovine leukaemia virus (BLV) infection is well documented and associated production losses make it one of the most important diseases of cattle, particularly in dairy cows. Any management interventions should be informed by an understanding of the herd-level and within-herd infection prevalence and of risk factors for spread of infection. Costs associated with blood tests have been a prohibitive factor in routine monitoring in domestic herds. A regional cross-sectional study was undertaken to estimate herd-level prevalence of BLV infection in commercial dairy herds and identify associated risk factors. Bulk tank milk (BTM) from 185 dairy herds randomly selected from Limpopo, North West, Mpumalanga, Gauteng and Free State provinces was tested for BLV infection using an indirect enzyme-linked immunosorbent assay (ELISA). A questionnaire was used to collect data regarding management practices and herdspecific factors. Logistic regression was used to assess factors associated with herd seropositivity. Multiple linear regression was used to identify factors associated with the quantitative outcome of the BTM ELISA (E quant), as a proxy for within-herd prevalence of BLV infection. Estimated herd-level prevalence was 96% (149/155; 95%CI 92-99%); it differed between provinces (P=0.001): 77% (17/22) in Mpumalanga, 97% (34/35) in Gauteng and 100% in North West (n=65), Free State (n=26) and Limpopo (n=3). Questionnaire data were obtained from 125 herds. No factors were significantly associated with herd BLV infection, likely due to the small number of negative herds. Use of communal calving camps, reuse of rectal gloves without disinfection and use of artificial insemination in cows were associated with higher E quant. Regular treatment against flies was associated with lower E quant. Infection with BLV is widespread amongst commercial dairy herds in the northern part of South Africa. Various aspects of herd management have been identified where interventions can be made to control of the disease.
Shotgun genome sequence and population diversity of Mannheimia haemolytica isolates from sheep in South Africa
(Pretoria : University of Pretoria, Faculty of Veterinary Science, 2017-09-07) Gelaw, Awoke K.; Cutler, Sally J.; Guthrie, Alan John; Fosgate, Geoffrey Theodore; University of Pretoria. Faculty of Veterinary Science. Dept. of Production Animal Studies; University of East London, UK; University of Pretoria. Faculty of Veterinary Science. Equine Research Centre; Agricultural Research Council. Onderstepoort Veterinary Research
Respiratory disease caused by Mannheimia haemolytica is a major economic and welfare concern in the cattle and small stock industry worldwide. Disease occurs due to the interaction of numerous factors, including weaning stress, shipment, inclement weather, and overcrowding coupled with viral and bacterial infections. The whole genome of M. haemolytica strain Mh10517 was analyzed using an Illumina MiSeq high throughput sequencing platform. The genome size is 2.67 Mb with 2,879 predicted gene sequences. The molecular evolution and relatedness of M. haemolytica was investigated using nucleotide sequence data of seven housekeeping gene fragments from 21 ovine isolates. MEGA version 7.0 genomic workbench was used for alignment and analysis of the nucleotide data sets. For each gene fragment, the sequences were compared and isolates with identical sequences were assigned the same allele number. Results suggested that the 21 isolates belonged to six sequence types (ST) and ST 28 accounted for 33% of the isolates. Neighbour joining method was used to produce dendograms based on the concatenated sequences of the seven loci in multilocus allelic profile. There was significant variation between the number of synonymous and non-synonymous substitutions between each sequence pairs (p=0.018) based on results from the Fisher’s exact test of neutrality of sequence pairs. These preliminary data show substantial sequence variations and this supports the hypothesis that ovine isolates of M. haemolytica are more diverse that what has been reported for isolates from other species. These results will advance studies on various aspects of the biology of M. haemolytica in Africa, and the world at large.
Serum albumin level of donor cows as indicator of development competence of oocytes
(Pretoria : University of Pretoria, Faculty of Veterinary Science, 2017-09-07) Smuts, M.P.; De Bruyn, S.; Thompson, P.N. (Peter N.); Holm, D.E. (Dietmar Erik); University of Pretoria. Faculty of Veterinary Science. Dept. of Production Animal Studies
Adequate nutrition is required for maintenance of normal production and reproduction in cattle. Strydom et al (2008) showed that albumin (the most abundant plasma protein) is the best predictor of malnourishment in South African cattle. Protein supplementation of in vitro embryo production (IVEP) media affects oocyte development into blastocysts. The objective of this study was to determine if serum albumin level of the donor cow could be used as a predictor of the developmental competence of oocytes, and if IVEP media can be optimised by additional protein supplementation for oocytes derived from donor cows with inadequate (≤35.9 g/l) levels of serum albumin. A total of 1024 oocytes were cultured during this prospective cohort study. Of these, 460 oocytes originated from cows with inadequate serum albumin levels and 564 from cows with adequate serum albumin (≥36.0 g/L). Oocytes of these two cohorts were randomly allocated to a control IVEP protocol or a protocol with additional protein supplementation. Mixed effects Poisson regression was performed for the number of oocytes that developed into blastocysts by the 7th day of culture. Adequate serum albumin level of donor cows independently resulted in 46% increased blastocyst formation in the control IVEP protocol (P = 0.02). Although protein supplementation of the IVEP protocol did not affect blastocyst formation in oocytes originating from cows with inadequate serum albumin, it independently reduced blastocyst formation by 30% in oocytes originating from cows with adequate serum albumin (P = 0.02). Other independent predictors of blastocyst outcome included higher serum urea nitrogen, lower beta-hydroxybutyric acid levels and lower fat grading of donor cows. It is concluded that adequate serum albumin of donor cows is a significant predictor of developmental competence of oocytes, and further research is required to determine optimal IVEP protein supplementation for oocytes originating from inadequately nourished cows. Vaccine matching: a different pathway to foot-and-mouth disease control Sirdar M.M.1, Blignaut B.1,2, Heath L.2, Gummow B.1,3, Fosgate G.T.1 1 Department of Production Animal Studies, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, 0110, South Africa; e-mail: sirdar44@hotmail.com 2 Transboundary Animal Diseases, Onderstepoort Veterinary Research, Agricultural Research Council, Onderstepoort, 0110, South Africa 3 College of Public Health, Medical and Veterinary Sciences, James Cook University, QLD, Australia Foot-and-mouth-disease (FMD) is a highly contagious transboundary animal disease that affects cloven-hoofed animals. Vaccination is one of the most important approaches for FMD prevention and control. In the vaccinated FMD protection zone of South Africa, cattle are routinely vaccinated every four months with a trivalent vaccine (South African Territories (SAT) serotypes 1, 2 & 3). Vaccine matching is used to select the most effective vaccine to use during outbreaks by comparing the antigenic variability between field and vaccine viruses. The objectives of this study were to assess the vaccine match of 40 FMD field viruses and to develop a new vaccine matching technique that can be used when live vaccine virus is not available in the laboratory. A diverse group of 20 SAT1 and 20 SAT2 isolates collected from 1990-2015 were selected for study. Virus neutralization tests (VNT) were performed following the method described in the OIE Manual (2012). Two sets of pooled sera were used for each serotype; vaccinated bovine sera (4 to 16 weeks postvaccination) and convalescent bovine sera collected 3 weeks post experimental challenge. Novel r1-values were calculated using a new vaccine matching technique that incorporated reference strain viruses in the absence of information concerning the homologous vaccine viruses. Ratios were also calculated for the vaccine titre compared to a standardized positive control. Standard deviation and coefficient of variation were used to assess variability in titre measures. Scatter plots and Spearman’s rank correlation coefficient were used to evaluate agreement between the two methods. The kappa statistic was also used to assess agreement based on a “adequate match” cutoff of 0.3 as stated in the OIE FMD Diagnostics Manual. These new methods provide a feasible, rapid and reliable vaccine matching approach that will contribute to control of FMD in southern Africa.
Ovarian dynamics and injection site reactions associated with immunocontraceptive zona pellucida (ZP) and GnRH vaccination of domestic horse mares (Equus caballus)
(Pretoria : University of Pretoria, Faculty of Veterinary Science, 2017-09-07) Nolan, Margaret Bethaline; Bertschinger, Hendrik Jan; Schulman, Martin L.; University of Pretoria. Faculty of Veterinary Science. Dept. of Production Animal Studies
Determinants when utilising veterinary immunocontraceptive vaccines include ovarian function and injection site reactions. Ovarian dynamics and injection site changes were monitored following administration of zona pellucida (ZP) and GnRH immunocontraceptive vaccines in 41 domestic horse mares. Mares were assigned to five treatment groups, stratified by age, parity and body condition score. Groups 1-4 treatments incorporated Pet Gel A (6%) and Poly (I:C) (500 μg) adjuvant in sterile water, in a two or three inoculation protocol 5 weeks apart, incorporating the following specified antigens in 1 ml total volume: no antigen (Group 1, n=9); initial 100 μg pZP then 100 μg pZP booster (Group 2, n=8); initial 500 μg recombinant zona pellucida (reZP) then 500 μg reZP and finally 500 μg reZP booster (Group 3, n=8) and initial100 μg pZP then 500 μg reZP booster (Group 4, n=8). Group 5 (n=8) received 2 ml of 400 μg GnRF-protein conjugate initially and as booster. Mares were examined by trans-rectal palpation and ultrasound of the reproductive tract at each treatment period. Injection site reactions were assessed by inspection and palpation using a three point scale and rectal temperature was measured for 7 days following treatments. Comparing functional ovarian status one month after final treatments demonstrated strongly significant differences between treatment groups (P<0.0001). Notably, a high proportion of both Groups 3 and 5 had ceased ovarian activity. The occurrence of injection site reactions and elevated body temperatures across all groups were mild, resolving one month after treatments, without any difference between treatment groups following initial or subsequent booster treatments. Using reZP vaccine may be indicated in mares where suppression of ovarian activity is a desirable outcome following immunocontraception. Incorporation of a Pet Gel A and Poly (I: C) adjuvant formulation provides an effective alternative to currently-utilised Freund’s adjuvants reportedly associated with adverse injection site reactions.
Cell death in the infundibulum and magnum regions of the oviduct in the domestic fowl (Gallus domesticus) during natural moulting
(Pretoria : University of Pretoria, Faculty of Veterinary Science, 2017-09-07) Mpango, M.M; Madekurozwa, Mary-Catherine; University of Pretoria. Faculty of Veterinary Science. Dept. of Anatomy and Physiology
The infundibular region of the oviduct has several functions including: engulfing the ovulated oocyte; providing a site for fertilization and forming the chalaziferous components of the developing egg. At approximately 18 months of age, laying hens enter the moulting phase of the reproductive cycle, during which egg production decreases or ceases due to oviductal regression. Although extensive research has been conducted on the effects of moulting on the physiological condition of hens, relatively little is known about the histomorphological changes which occur in the oviduct during this process. The present study was undertaken to compare the histomorphology of the infundibular epithelium in laying and moulting commercial hens. A total of 10 laying (32 weeks old) and 10 moulting (75 weeks old) commercial hens were used in the present study. Tissue samples from the infundibulum were fixed in buffered neutral formalin for 5 days. The samples were later processed routinely for light microscopy and stained with haematoxylin and eosin, as well as Periodic acid Schiff-Alcian blue (PAS-AB). The infundibulum was sub-divided into proximal funnel and distal tubular regions. In laying hens the funnel region was lined by a ciliated simple columnar epithelium. In moulting hens this region displayed localized areas of swollen, nonciliated cells with pale-staining cytoplasm and nuclei. The tubular infundibular region in laying hens was lined by a pseudostratified columnar epithelium composed of ciliated and non-ciliated cells. The latter cells stained positive for PAS indicating the presence of neutral mucins. The epithelium in the tubular region of moulting birds contained cells at different stages of degeneration. Alcian blue, as well as PAS- AB cells were observed, indicating the presence of acidic and mixed mucins. The results of the study indicate that the infundibular epithelium differs histologically and physiologically during the laying and moulting phases of the reproductive cycle.
Towards a yellow tulp vaccine : preliminary studies exploiting the potential for cross-reactivity with related bufadienolides
(Pretoria : University of Pretoria, Faculty of Veterinary Science, 2017-09-07) Isa, Hamza Ibrahim; Ferreira, A.; Crafford, Jan Ernst; Botha, C.J. (Christoffel Jacobus); University of Pretoria. Faculty of Veterinary Science. Dept. of Paraclinical Sciences; University of Pretoria. Faculty of Veterinary Science. Dept. of Veterinary Tropical Diseases; University of Pretoria. Faculty of Veterinary Science. Dept. of Pharmacology and Toxicology
Poisoning by Moraea pallida Bak. (yellow tulp) is the most important of all cardiac glycoside induced toxicoses which collectively account for 33% and 10% of deaths in large and small stock due to plant poisoning, respectively, in the Republic of South Africa. This study was conducted to investigate the potential for developing a vaccine against epoxyscillirosidine, the toxin contained by yellow tulp. Epoxyscillirosidine was extracted, isolated, purified and confirmed using 13C NMR spectroscopy. Bufalin and proscillaridine were purchased and together with epoxyscillirosidine were coupled to BSA and KLH to render them immunogenic. The immunogens (4 mg/ml) were emulsified with an equal volume of Montanide ISA, as an adjuvant. Adult male New Zealand White rabbits (n=15) were randomly assigned to 5 equal groups. Rabbits in groups I, II, III and IV were immunized with proscillaridine-BSA, bufalin-BSA, epoxyscillirosidine-KLH and epoxyscillirosidine-BSA conjugates, respectively. Group V served as control where animals were administered BSA only. The rabbits were immunized on Days 0, 21 and 42 by intradermal injection of 0.1ml of the vaccine at four sites on the dorsum. Blood was collected prior to each vaccination and on Day 67. An ELISA was performed to determine antibody response. Antibodies were raised against proscillaridine, bufalin and epoxyscillirosidine. Furthermore, the antibodies synthesized by Group I and II rabbits also cross-reacted with epoxyscillirosidine. However, the degree of cross-reactivity was low. This may be enhanced by optimizing the vaccine to induce stronger antibody response. The antibodies will be evaluated to determine the neutralization efficacy against epoxyscillirosidine.
Evaluation of leaf extracts of several tree species for activity against Salmonella
(Pretoria : University of Pretoria, Faculty of Veterinary Science, 2017-09-07) Gado, Dorcas A.; Ahmed, Aroke Shahid; Botha, Francien Susanna; Ehlers, Marthie Magdaleen; McGaw, Lyndy Joy; University of Pretoria. Faculty of Veterinary Science. Dept. of Paraclinical Sciences; University of Pretoria. Faculty of Health Sciences. Dept. of Medical Microbiology
Handling and consumption of contaminated foods (meat, milk and eggs) are considered a major source of infection in humans. This public health risk reinforces the need for close monitoring and collaboration between public health and veterinary authorities to mitigate the risk at the humananimal interface necessary for health and food security. Gastroenteritis that is not self-limiting is mostly treated with a wide range of antibiotics. The indiscriminate use of these antibiotics has resulted in the upsurge of resistant and multiresistant strains of bacteria. This complicates treatment, especially in patients with human immunodeficiency virus (HIV) infection, necessitating the search for novel, cheaper, safer and efficacious antibacterial products. Recent in vitro studies have revealed that indigenous South African plants possess antimicrobial properties against gastrointestinal disorders and diarrhoea-causing organisms. In a preliminary screening, the antibacterial activities of acetone, ethanol, methanol and water extracts of the leaves were determined using a two-fold serial microdilution method against a range of pathogenic bacteria (Staphylococcus aureus, Enterococcus faecalis, Bacillus cereus, Escherichia coli, Salmonella Typhimurium and Pseudomonas aeruginosa). The plant species investigated were Protorhus longifolia, Searsia leptodictya, Carissa macrocarpa, Combretum bracteosum, Kirkia wilmsii, Loxostylis alata, Brachychiton acerifolium, Brachychiton bidwillii, Noltea africana and Blighia unijugata. All the extracts had activity against at least one of the test organisms over an incubation period of 24 hours. The average MIC values of the plant extracts against the different bacteria ranged from 0.2 mg/ml to 1.4 mg/ml. The Gram-positive bacteria (S. aureus, B. cereus and E. faecalis) were more susceptible to the plant extracts than the Gramnegative bacteria (E. coli, S. Typhimurium and P. aeruginosa). P. longifolia and L. alata extracts were the most active against nearly all the bacteria tested with MIC values as low as 0.02 mg/ml. L. alata was selected for further work to isolate compounds active against Salmonella species.
Effect of usage / non-usage of antibiotics on virulence profiles of Escherichia coli in pig production
(Pretoria : University of Pretoria, Faculty of Veterinary Science, 2017-09-07) Abubakar, R.H. (Rukayya Hussain); Madoroba, Evelyn; Kamutando, Casper N.; Valverde, Alexander; Cowan, Don A.; Fasina, Folorunso Oludayo; University of Pretoria. Faculty of Veterinary Science. Dept. of Veterinary Tropical Diseases; Agricultural Research Council. Onderstepoort Veterinary Research. Bacteriology Section; Food and Agriculture Organization of the United Nations; University of Pretoria. Dept. of Genetics. Centre for Microbial Ecology and Genoics
Pathogenic Escherichia coli pathogens are responsible for acute profuse diarrhoea in growing pig with resultant high morbidity and mortality. Enterotoxigenic E. coli (ETEC) encoding STa, STb, EAST1 and LT enterotoxins and Shiga toxin E. coli (STEC) encoding Stx2e occur most commonly in pigs. This study investigated the prevalence of ETEC and VTEC virulence genes in two groups of growing pigs (five piglets per group) kept under routine farm management practices. One group was administered antibiotics and the other group received no antibiotics. A total of 241 E.coli strains were isolated in piglets from both groups between 0 and 70 days of age. Virulence genes were detected by PCR in 24.8% (18.2 - 32.7) of the antibiotic group isolates and 43.5% (34.5 - 52.9) of the non-antibiotic group with a significant difference (P = 0.002). The proportions of the virulence genes STa, STb, EAST1 and Stx2e were 18.1% (8.61 - 34.39), 0% (0.0 - 10.43), 78.7% (62.25 - 89.32) and 3% (0.53 - 15.32) in the antibiotic group respectively, and 14.8% (7.40 - 27.68), 8.5% (3.36 - 19.93), 85.1% (72.32 - 92.59) and 12.7% (5.98 - 25.17) in the non-antibiotic group respectively. AIDA1 was the most dominant non-fimbrial adhesion factor while F6 was the only fimbrial factor detected. Twelve pathotypes were identified, with pathotype EAST1 being the most prevalent. The study showed that usage/non-usage of antibiotics in growing pigs does not prevent occurrence of disease causing virulence genes and other factors may be involved.
A comparison between manual count, flow cytometry and qPCR as a means of determining Babesia rossi parasitaemia in naturally infected dogs
(Pretoria : University of Pretoria, Faculty of Veterinary Science, 2017-09-07) De Villiers, Lourens; Quan, Melvyn; Troskie, Milana; Fosgate, Geoffrey Theodore; Leisewitz, Andrew L.; University of Pretoria. Faculty of Veterinary Science. Dept. Of Companion Animal Clinical Studies; University of Pretoria. Faculty of Veterinary Science. Dept. of Veterinary Tropical Diseases; University of Pretoria. Faculty of Veterinary Science. Dept. of Production Animal Studies
Parasite quantification is crucial to understand disease pathogenesis. An automated method of determining parasite density would facilitate higher throughput and provide results that are more objective. The study objectives included: a) validating the use of flow cytometry to detect and quantify Babesia rossi nucleic acid; b) comparing B. rossi parasite density in venous blood quantified by manual count, flow cytometry and quantitative real-time PCR (qPCR) in the same dog; and c) comparing the parasite density of B. rossi in capillary blood (quantified by manual count), with the parasite density in venous blood, as determined by manual count, flow cytometry and qPCR in the same dog. Peripheral capillary and central venous blood was sampled from 40 naturally B. rossi-infected dogs and 10 healthy control dogs. Samples were analyzed by reverse line blot to confirm a mono-B. rossi infection. Capillary blood parasite density was quantified using light microscopy (manual counts) and venous blood parasitaemia quantified using manual counts, flow cytometry and qPCR. Flow cytometry, using SYBR Green I staining, showed promise in quantifying B. rossi nucleic acid in venous blood. Non-parametric methods were used for statistical analysis. Spearman’s rho revealed a significant correlation between the venous manual counts and both flow cytometry (rs = 0.467; P = 0.001) and qPCR (rs = -0.813; P < 0.001), as well as a significant correlation between the capillary manual counts compared to venous manual counts (rs = 0.793; P < 0.001), flow cytometry (rs = 0.400; P = 0.004) and qPCR (rs = -0.760; P < 0.001). Preliminary results suggest that both flow cytometry and qPCR may be of value as an alternative to the gold standard (manual count) for quantifying B. rossi parasitaemia in canine whole blood.
Pharmacological investigation of medicinal plants used traditionally in southern Africa to treat gastrointestinal nematode infections of small ruminants
(Pretoria : University of Pretoria, Faculty of Veterinary Science, 2016-08-25) Sakong, B.M. (Bellonah Motshene); Ahmed, Aroke Shahid; Adamu, Matthew; Naidoo, Vinny; Eloff, Jacobus Nicolaas; McGaw, Lyndy Joy; University of Pretoria. Faculty of Veterinary Science. Dept. of Paraclinical Sciences; University of Pretoria. Faculty of Veterinary Science. Biomedical Research Centre; University of Agriculture, Makurdi. Faculty of Veterinary Medicine. Dept. of Pharmacology
Haemonchus contortus is a major gastrointestinal helminth parasite causing haemonchiasis in production animals. Infections are characterized by fever, anaemia, weight loss and ultimately death. Haemonchiasis is a serious economic challenge globally resulting in poor reproductive efficiency, increased susceptibility to bacterial and fungal infections, as well as low production of wool, milk and meat. Treatments with synthetic drugs are currently the only effective way to control the infestation. Albendazole is a drug of choice against this parasite; it acts by binding to tubulins and causes depolymerisation of microtubules. No other anthelminthic compounds of comparable efficacy are available yet and there is a critical need to find alternative drugs. An alternative strategy is to investigate ethnoveterinary plants with putative anthelminthic properties. The aim of this study was to evaluate selected plant extracts for anthelmintic activity in vitro against Haemonchus contortus, as well as antifungal activity to determine correlations in these activities. Cytotoxicity of the plant extracts was also tested, and isolation of compounds was performed. The crude extracts of Diospyros whyteana and Peddiea africana showed low cytotoxicity with LC50 greater than 1 mg/ml. Good antifungal activity was observed in D. whyteana, Peddiea africana and Schotia brachypetala with MICs ranging from 40-160 mg/ml against Candida albicans and selectivity index (SI) values from 6.25-12.5. In the egg hatch inhibition assay, D. whyteana had good results with EC50=0.7377 mg/ml for acetone while water extracts were 1.508, thus the SI ranged from 0.66 to 1.35. Water extracts showed better anthelmintic activity compared to acetone extracts of D. whyteana, P. africana and Schotia brachypetala. The extracts had good activity in the egg hatch assay, good antifungal activity, and they were non-toxic to Vero cells. Four bioactive compounds have been isolated from Diospyros whyteana with excellent activity against Candida albicans and the structures of these are being determined.
Identifying high risk areas for foot-and-mouth disease (FMD) outbreaks in South Africa
(Pretoria : University of Pretoria, Faculty of Veterinary Science, 2016-08-25) Sirdar, Mohamed Mahmoud; Blignaut, Belinda; Gummow, Bruce; Fosgate, Geoffrey Theodore; Mampane, R.L.; Rikhotso, Boetie Oupa; Du Plessis, B.; University of Pretoria. Faculty of Veterinary Science. Dept. of Production Animal Studies; South Africa. Agricultural Research Council. Onderstepoort Veterinary institute; South Africa. Dept. of Agriculture and Rural Development; James Cook University. Medical and Veterinary Sciences. College of Public Health
Foot-and-mouth disease (FMD) is a controlled (notifiable) disease in accordance with the South African Animal Diseases Act (Act 35) of 1984. In 1996, the International Committee on FMD of the OIE endorsed South Africa’s FMD free status without vaccination. According to the OIE status, the areas excluded from the free zone were the endemically infected Kruger National Park and the FMD protection areas. During the previous 15 years, at least one FMD outbreak has occurred per year in the protection zone with the exceptions being 2005, 2007, and 2014. Continuing outbreaks threaten the FMD-free status of the country; outbreaks raise concerns about the efficiency and sustainability of FMD control measures within the protection areas. The objective of the study was to develop isopleth risk maps in effort to identify high risk areas in Mpumalanga and Limpopo Provinces. Data were collected from provincial veterinary services and World Animal Health Information Database (WAHIS) Interface for the period 2005-2015. Cattle affected by the Southern African Territories serotypes 1 and 2 of FMD Virus were selected for modelling. The proportion of affected cattle at the dip-tank level was calculated and used as the dependent variable. Data were assessed for normality by plotting histograms, calculating descriptive statistics, and performing the Anderson-Darling test for normality. Data for each serotype and a combined analysis were interpolated using ordinary kriging of reported outbreaks. Moran’s I was used to estimate the spatial autocorrelation of FMD outbreaks in cattle within the protection zone of South Africa. Data presented can assist with strengthening current FMD control measures and subsequently contribute to the development of further quantitative models.
Prevalence of and risk factors for feline hyperthyroidism in South Africa
(Pretoria : University of Pretoria, Faculty of Veterinary Science, 2016-08-25) McLean, Joanne Leslie; Lobetti, R.G. (Remo Giuseppe); Thompson, P.N. (Peter N.); Schoeman, Johan P.; University of Pretoria. Faculty of Veterinary Science. Dept of Companion Animal Clinical Studies; University of Pretoria. Faculty of Veterinary Science. Dept. of Production Animal Studies; Bryanston Veterinary Hospital
Feline hyperthyroidism is a disease of middle-aged to older cats that has shown a marked increase in worldwide incidence within the last three decades as well as a marked geographic variation in prevalence. The exact pathogenesis of the disease still remains obscure and despite a plethora of epidemiological studies, clear risk factors have not been identified. The purpose of this study was to determine the prevalence of feline hyperthyroidism in South Africa and to identify potential risk factors. Serum total thyroxine (tT4) and thyroid stimulating hormone (cTSH) were measured in 302 cats aged 9 years and older that were presented at various veterinary clinics. In a few cats, serum free thyroxine (fT4) was also measured. At the time of blood sampling a questionnaire was completed regarding vaccination history, internal and external parasite control, diet and environment. The prevalence of hyperthyroidism (tT4> 50nmol/L or tT4 between 30-50 nmol/L with cTSH < 0.03ng/ml and fT4> 50pmol/L) within this population was 7.0% with no significant difference in prevalence between healthy (5.1%) and sick (8.2%) cats. Cats ≥ 12years of age (OR= 4.3, p= 0.02) and cats with canned food in their diet (OR= 2.1, p= 0.1) were more likely to be diagnosed with hyperthyroidism. No significant relationship between vaccinations, parasite control or indoor environment and hyperthyroidism was observed. Hyperthyroid cats were more likely to present with weight loss (OR= 3.2, p= 0.01) and with a heart rate ≥ 200bpm (OR= 5, p= 0.01) than cats without the disease.The prevalence of feline hyperthyroidism in South Africa appears to be similar to that in cats in Japan and Portugal but less than that in cats in the UK and Germany. Risk factors for hyperthyroidism, previously found in other studies, specifically older age and eating canned food was present in this study population.
Mortality rates and survival analysis of owned, free-roaming dogs in a resource-limited community, Bushbuckridge, South Africa
(Pretoria : University of Pretoria, Faculty of Veterinary Science, 2016-08-25) Kolo, Francis Babaman; Conan, Anne; Henning, Alischa; Clift, Sarah Jane; Knobel, Darryn Leslie; University of Pretoria. Faculty of Veterinary Science. Dept. of Veterinary Tropical Diseases; University of Pretoria. Faculty of Veterinary Science. Dept. of Production Animal Studies; Ross University. School of Veterinary Medicine
Canine rabies can be successfully controlled in dogs through mass vaccination. In populations of free-roaming dogs in resource-limited settings, the maintenance of herd immunity through vaccination is challenged by the high population turnover. Understanding and describing mortality in these populations may therefore assist in the control of rabies. The objective of this study was to determine the rates and causes of mortality in owned, free-roaming dogs in Hluvukani village, Bushbuckridge, South Africa, from May 2014 through July 2015. From the Health and Demographic Surveillance System in Dogs in Hluvukani village, we followed a nested cohort of dogs one year and older over a 12-month period and puppies born to the cohort for 120 days, from May 2014. Deaths were recorded and investigated through verbal autopsy and post-mortem examination. Survival rates from enrolment (adults) or from birth (puppies) were compared using Cox proportional hazard regression models. Of the cohort of 367 adult dogs (203 males and 164 females), 27 died during the follow-up period. The mortality rate was 78 per 1,000 dog-years in the cohort. Adult females had a shorter survival time from enrolment (mean = 341.7 days) compared to adult males (mean = 356 days; p = 0.05). No difference in survival was detected between age groups. Enrolled litters were 62 and 329 enrolled puppies, 135 died before 120 days of age. Mortality in puppies was high with 2,390 deaths per 1,000 dog-years recorded, and a mean survival time of 60 days. No difference in survival was observed between males and females (p = 0.3). In adults and puppies, causes of death were identified as natural (43%), non-natural (53%) and euthanasia (4%). Mortality was low in adult dogs, but very high in the puppies. Despite high population turnover through births and deaths, the vaccination coverage was still sufficient to prevent rabies outbreaks in the village.
Determining the adrenocortical activity as a measure of stress in domestic pigs (Sus scrofa domesticus) based on salivary and faecal analysis
(Pretoria : University of Pretoria, Faculty of Veterinary Science, 2016-08-25) Mangwiro, Nobert; Ganswindt, Andre; Fasina, Folorunso Oludayo; University of Pretoria. Faculty of Veterinary Science. Dept. of Production Animal Studies; University of Pretoria. Faculty of Veterinary Science. Dept. of Anatomy and Physiology; University of Pretoria. Faculty of Veterinary Science. Dept. of Veterinary Tropical Diseases
Domestic pigs are subjected to farm management procedures, some of which might be perceived as causing stress and therefore may have welfare concerns. When confronted with a stressor, animals display a response that consists of a suite of physiological and behavioural alterations to restore homeostasis. Physiologically, the response is usually determined using glucocorticoid concentrations (GC) albeit invasively, with the disadvantage of a possible handling-induced stress response. To date, no non-invasive method exists for determining stress-related responses in pigs. This study aimed to examine the suitability of enzyme-immunoassays (EIAs) for determining GC concentrations in saliva and faeces of domestic pigs by performing an ACTH challenge. A total of 6 animals were studied with 4 receiving 10µg/kg of Synacthen® (Novartis, South Africa Pty Ltd) and the remaining 2 receiving 0.5 ml physiologic saline. Baseline salivary glucocorticoid (sGC) concentrations of 2.38±1.83ng/ml (mean±SEM) increased by six-fold (14.03±6.83 ng/ml) within 40-90 minutes after administration of ACTH (P < 0.0001) and the elevated salivary cortisol levels were maintained for up to nine hours. Administration of saline caused no significant differences in sGC concentrations (P = 0.82). Similarly, baseline faecal glucocorticoid metabolite (fGCM) level of 235±46μg/g rose significantly up to 393±164μg/g within 36 hours post ACTH administration (P < 0.0001). No significant difference was found between baseline and post saline administration (P = 0.57). Significantly higher sGC concentrations were found in samples collected in the morning compared to those collected in the afternoon, indicating a circadian rhythm. In terms of stability of fGCMs, post-defecation levels only changed by 4% over the course of 50h (P = 0.76). In conclusion, EIAs can be used to determine sGC and fGCM concentrations to assess adrenocortical function in pigs. FGCM levels are relatively stable for at least two days post-defecation, which facilitates field sample submissions.
In silico functional prediction and characterization of selected Theileria parva hypothetical proteins
(Pretoria : University of Pretoria, Faculty of Veterinary Science, 2016-08-25) Mahlobo, Bongiwe Priscah; Mokoena, F.; Matjila, Paul Tshepo; Sibeko-Matjila, Kgomotso Penelope; University of Pretoria. Faculty of Veterinary Science. Dept. of Veterinary Tropical Diseases; University of Pretoria. Faculty of Veterinary Science. Dept. of Life and Consumer Sciences
Cattle theileriosis is infamous for hampering the economic development of south, central and east African countries due to exorbitant numbers of cattle mortalities. The disease is caused by Theileria parva, an important tick-transmitted haemoprotozoan parasite that belongs to the phylum Apicomplexa. Infection of cattle with cattle-derived T. parva isolates is responsible for East Coast fever while infections by buffalo-derived isolates results in Corridor disease. A transcriptome study comparing two T. parva isolates, representing cattle- and buffalo-derived parasites, identified 1089 differentially expressed transcripts (DETs). Analysis of DETs revealed 593 (54.4%) hypothetical proteins (HPs). These proteins are believed that they could be crucial in understanding the diseases caused by T. parva infections. Thus, this study purposed to characterize these proteins. The initial screening using sequence similarity searches led to designation of sequence descriptions for 284 HPs; this report focuses on the analysis of the remaining 309. Applying an integrated bioinformatics approach including a variety of domains discovery tools, protein family classification systems and approaches that are based on amino acid sequence characteristic, as well as 3D structures predictions, functions of these HPs were predicted. Furthermore, information of functionally characterized homologs, subcellular localization and functional partners of HPs was considered in the analysis. Overall, n = 193 HPs were successfully annotated for function and some of these were virulent proteins, significant in the survival of the pathogen in the host. Subcellular localization revealed three HPs that could be investigated as possible therapeutic targets. Secretome analysis revealed 57 HPs containing signal peptides, suggesting possible interactions with the host. The results of this study will facilitate a better understanding of the mechanism of pathogenesis of cattle theileriosis caused by T. parva and development of more effective disease control strategies.
Is being with girls stressful? Social environment influences hormone levels in male giraffes
(Pretoria : University of Pretoria, Faculty of Veterinary Science, 2016-08-25) Wolf, Tanja Esther; Bennett, Nigel Charles; Burroughs, Richard E.J.; Ganswindt, Andre; University of Pretoria. Faculty of Veterinary Science
Giraffes (Giraffa camelopardalis giraffa) live in a fission-fusion social system, characterized by the splitting and reunion of subgroups within a larger social network. Adult bulls show a roaming tactic to search for fertile females, whereas younger bulls are often seen in all male groups. In this study we combined behavioural observations with hormonal data. Therefore, a giraffe population of about 80 individuals (11 adult males, 28 adult females, and 32 juvenile / sub-adult animals) was monitored six days a week from dawn to dusk for a period of 12 months (Nov 2014–Oct 2015). Giraffes were individually identified by their unique pelage pattern and adult bulls assigned to age classes based on their appearance (A, B, and C), with class A bulls being the oldest and tallest. A total of 790 faecal samples were collected and analysed for faecal androgen (fAM) and glucocorticoid metabolite (fGCM) concentrations. Class A bulls show significantly higher fAM levels compared to younger bulls, with lowest fAM levels found for the juvenile / sub-adult group. Longer periods of increased fAM levels in the oldest bulls mainly occur during summer and are associated with an observed birthing peak. Within class A, fAM levels of bulls in all male groups are significantly lower than when associated with females, however, these levels are still significantly higher compared to respective fAM levels from youngest males. No significant differences in overall fGCM levels could be found between the different age classes. However, within class A the bulls show a trend for higher fGCM levels when sexually active compared to when associated with an all-male group. In contrast, juvenile / sub-adult bulls show highest fGM levels when they are in all-male groups, which is possibly linked to intrasexual competition as younger bulls still need to establish their position within the hierarchy.
Poo’s potential – can we link different land use practices to stress-related hormone levels in leopards (Panthera pardus)?
(Pretoria : University of Pretoria, Faculty of Veterinary Science, 2016-08-25) Webster, A.B. (Andrea); Burroughs, Richard E.J.; Laver, Peter N.; Ganswindt, Andre; University of Pretoria. Faculty of Veterinary Science
The leopard’s versatility as a generalist predator facilitates occupation of a wide range of habitats. Although protected areas are important for the conservation of this species, the majority of suitable leopard habitat lies beyond protected area boundaries. Leopards utilizing areas under different anthropogenic influences may therefore be exposed to different environmental, physiological, and psychosocial stressors. This study aims to examine the suitability of enzymeimmunoassays for monitoring adrenocortical function in the leopard based on faecal glucocorticoid metabolite (fGCM) analysis by performing an adrenocorticotropic hormone (ACTH) challenge test. Subsequently the study will investigate variations in fGCM concentrations of animals under different anthropogenic influences to identify the potential extrinsic and intrinsic stressors linked to different land use types. The ACTH challenge will be performed on one adult male and one adult female housed at Predator World in the Northwest Province. In addition, gastrointestinal transit time will be determined in 10 animals housed at different captive facilities in the North West, Mpumalanga, and Gauteng Provinces. A potential aging effect of the hormone matrix will be investigated by determining the rate of metabolism of fGCMs post-defaecation. Finally, faecal samples from free-ranging leopards in protected and unprotected areas of Mpumalanga and Limpopo provinces including the Sabi Sands Game Reserve, Guernsey, the Hoedspruit Wildlife Estate and surrounds, will be collected over a period of 6 months. The ability to reliably assess adrenocortical function in leopards will provide a solid foundation from which to further examine endocrine responses to recognised stressors in this iconic African species. Specifically, our study will help to untangle some of the wildlife management, conservation, and human-predator conflict mitigation challenges faced by free-raging leopards at the human-domestic-wildlife interface.
Initial blood urea nitrogen concentration predicts subsequent blood urea nitrogen concentration in beef cows
(Pretoria : University of Pretoria, Faculty of Veterinary Science, 2016-08-25) Tshuma, Takula; Fosgate, Geoffrey Theodore; Hamman, Robyn; Holm, Dietmar Erik; University of Pretoria. Faculty of Veterinary Science
This study was performed to determine whether beef cows have an inherent ability to maintain their relative blood urea nitrogen (BUN) concentration when cattle are exposed to varying levels of dietary nitrogen supplementation. Ten Hereford and 11 Nguni cows, aged between 2 and 16 years, were utilised in two crossover designs. In the first design, cows were exposed to diets containing normal and high crude protein (CP) levels. At the end of the first crossover design, cows received a normal diet for one week before commencement of the second design. In the second crossover design, cows were fed diets containing normal and low CP levels. Blood urea nitrogen concentration was measured 17-21 times (mean = 20) during the study. A linear mixed-effects model was used to assess whether baseline BUN concentration (measured one week before onset of the study) was predictive of subsequent BUN concentration in individual cows. The model was also used to assess whether any of the measured variables were predictive of subsequent BUN concentrations. Baseline BUN concentration was a significant predictor of subsequent BUN concentration in individual cows (P = 0.004). Other variables that were significantly associated with subsequent BUN concentration were breed (P = 0.033), the diet that the cows received before the current treatment (P < 0.001), treatment (P < 0.001) and the week during which sampling was performed (P < 0.001). Beef cattle appear to have an inherent ability to maintain their relative BUN concentration within herds despite changes in levels of dietary nitrogen supplementation.

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