Comparison of two culture techniques used to detect environmental contamination with Salmonella enterica in a large-animal hospital

Salmonellosis is a common healthcare-associated infection in large-animal hospitals, and surveillance for Salmonella is an integral part of comprehensive infection control programmes in populations at risk. The present study compares the effectiveness of two culture techniques for recovery of Salmonella from environmental samples obtained in a large-animal referral veterinary hospital during a Salmonella outbreak. Environmental samples were collected using household cleaning cloths that were incubated overnight in buffered peptone water (BPW). Aliquots of BPW were then processed using two different selective enrichment and culture techniques. In the first technique (TBG-RV-XLT4) samples were incubated at 43 °C in tetrathionate broth and then Rappaport-Vassiliadis broth before plating on XLT4 agar. The second technique (SEL-XLD) involved incubation at 37 °C in selenite broth before plating on XLD agar. Salmonella was recovered from 49.7% (73/147) of samples using the TBG-RV-XLT4 technique, but only 10.2% (15/147) of samples using the SEL-XLD method. Fourteen samples (9.5%) were culture-positive using both methods, and 73 (49.7%) were culture-negative using both techniques. There were discordant results for 60 samples, including 59 that were only culture-positive using the TBG-RV-XLT4 method, and one sample that was only culturepositive using the SEL-XLD method. Salmonella was much more likely to be recovered using the TBG-RV-XLT4 method, and there appeared to be five times more false-negative results using the SEL-XLD technique. Environmental contamination with Salmonella may be underestimated by certain culture techniques, which may impair efforts to control spread in veterinary hospitals

The use of electrochemically activated saline as a uterine instillation in pony mares

Twelve pony mares were randomly assigned to either a control or a treatment group and inseminated with fresh, raw semen from a single stallion of known fertility in a cross-over trial design. Pregnancy was diagnosed by transrectal ultrasound 12-14 days post-ovulation and then terminated by administration of a luteolytic dose of cloprostenol. Treatment mares received a uterine instillation of 100 m of electrochemically activated (ECA) saline 4-12 hours post-insemination. Control mares received no treatment post-insemination. Per cycle pregnancy rate was 58.3 % in the control group and 50 % in the treatment group. There was no statistical difference (P = 1.000) in pregnancy rate between the 2 groups. The principles of ECA and applications of ECA saline are discussed

Prevalence of methicillin-resistant Staphylococcus aureus among large commercial pig herds in South Africa

The prevalence of nasal carrier status of methicillin-resistant Staphylococcus aureus (MRSA) in pigs has been described elsewhere, but is unknown in South Africa. To address concerns that exist regarding the zoonotic risk that carriers pose to workers, the herd-level prevalence of MRSA was determined among 25 large (> 500 sows) commercial pig herds in South Africa, representing 45% of the large commercial herds in the country. From each herd, the nasal contents of 18 finisher pigs were sampled at the abattoir, pooled into three and selectively cultured to determine the presence of MRSA. A herd was classified as MRSA-positive if one or more of the three pooled samples cultured positive. Three of the 25 herds tested positive for MRSA, equating to a 12% herd prevalence (95% CI: 7% – 23%) among South African commercial piggeries. The prevalence of nasal MRSA carriers among large commercial pig herds in South Africa was low compared to what has been reported elsewhere and suggests a relatively low zoonotic MRSA risk to workers in South African commercial piggeries and abattoirs

Mechanisms by which lumpy skin disease virus is shed in semen of artificially infected bulls

Lumpy skin disease (LSD) is a disease of significant economic importance in Africa. It causes considerable production losses and its presence in semen is a constraint to international trade. Recent findings that LSDV viral DNA can be found in the semen of artificially infected bulls for up to five months, while viable virus could be isolated 42 days after infection, indicated the need for studies into the mechanism by which this protracted shedding occurs. Six healthy, seronegative, postpubertal Dexter bulls were housed in vector-free stables and challenged with LSD virus by intravenous injection. Sheath washes, vesicular fluid and semen collection was performed every other day and subjected to PCR. On these days, blood was collected for serum neutralization tests and virus isolation, and ultrasonography of the reproductive tracts performed. Semen was centrifuged to separate cell-rich and seminal plasma fractions, and tested by PCR. Clinical parameters were recorded twice daily. Bulls shedding viral DNA 28 days after challenge were slaughtered, their reproductive tracts were harvested and diagnostic post mortem was performed. Histopathology, immunoperoxidase staining, electron microscopy, virus isolation and PCR were done on tissue samples. Of the six bulls, two showed no clinical signs, two showed mild and two showed severe clinical signs. Fever appeared five to seven days and lesions eight to ten days post challenge. Bulls were viraemic and febrile during the same time. Viral DNA was detected in all semen fractions of all bulls, but mostly from the cell-rich fraction and from the bulls showing the most severe clinical signs. Ultrasonography showed infarction in the testes and epididymides of the two bulls that were most severely affected. Necropsy of the two bulls that were still shedding after 28 days showed testicular degeneration and infarction, as well as epididymal granuloma formation. None of the accessory sex organs showed significant pathology. Histopathological changes seen were necrogranulomata in testes and peididymides. IMP staining of reproductive tissues showed that staining was restricted to areas in the testes and epididymides that were associated with necrosis. Virus could be seen on negative staining EM of sections of the testes. Our results show that LSDV is not limited to specific fractions of the ejaculate and that the testes and epididymides are most profoundly affected. Blood contamination is not responsible for the presence of viral DNA in semen, and it is unlikely that the virus is sperm-associated. Results suggest that the ejaculate is contaminated with viral DNA as it is shed from necrotic lesions in the genital tract. Further research is indicated into the ability of infected semen to produce disease as well as treatment protocols that could render semen free of viral DNA.Dissertation (MMedVet (Theriogenology))--University of Pretoria, 2006.Production Animal Studiesunrestricte

Educational value of group learning activities in MBA education : student perceptions and instructor intentions

The objectives of this study were to assess the perceptions of educational value of group learning held by students and compare it with the intentions of lecturers involved in the MBA programme. Eighty-two MBA students enrolled at the Gordon Institute of Business Science (GIBS) of the University of Pretoria completed an online questionnaire, the results of which reflected an overall positive perception of educational value of group learning. However, negative perceptions of group dynamics, fairness and administrative processes also surfaced. There appears to be some evidence of racial undertones to the negative perceptions. These perceptions were significantly different between junior and senior students. Semi-structured interviews with lecturers and administrative staff revealed markedly different intentions and approaches to group learning. An awareness of the difficulties faced by students in group activities could be demonstrated, but different opinions were held on appropriate interventions. The study concludes with suggestions to improve identified weaknesses through a more focused educational approach. Such an approach would place greater emphasis on personal reflection and addressing of dysfunctional behaviour in groups, as part of a posited central skill in management.CopyrightDissertation (MBA)--University of Pretoria, 2012.Gordon Institute of Business Science (GIBS)unrestricte

Prevalence of Salmonella in juvenile dogs affected with parvoviral enteritis

Salmonellosis is a disease of major zoonotic importance and canine parvovirus is a potentially fatal cause of canine enteritis with a world-wide distribution. Persistent isolation of Salmonella during routine environmental sampling surveys of a hospital ward, reserved for the treatment of dogs with canine parvovirus infection, prompted investigation into a possible source. We hypothesised that dogs affected by canine parvovirus would have a higher prevalence of faecal salmonellae compared to an apparently healthy cohort. Seventy-four client-owned dogs naturally infected with canine parvovirus and 42 apparently healthy client-owned dogs were included in the study. This prospective, longitudinal, observational study was conducted over an 18-month period. Fresh faecal samples were collected from dogs aged 6 weeks to 9 months diagnosed with canine parvovirus infection and admitted for treatment, and from apparently healthy dogs presented for vaccination or routine hospital procedures. Faeces were submitted for the isolation, antimicrobial susceptibility testing and serotyping of salmonellae. The prevalence of faecal Salmonella shedding was 22% and 31% for the affected and apparently healthy dogs, respectively, which was not statistically different. No significant associations between Salmonella status and possible risk factors or continuous variables such as age, body weight and duration of hospitalisation were identified. All the Salmonella isolates (n = 32) were resistant to penicillin G, lincomycin and tylosin. Salmonellae from nine different serotypes were identified. The prevalence of Salmonella shedding in both groups was higher than that commonly reported, yet similar to those in previous reports on young dogs, shelter dogs or dogs fed a raw meat diet

Anthelmintic resistance of gastrointestinal nematodes in dairy calves within a pasture‐based production system of south West Western Australia

The objective of this study was to determine the prevalence of gastrointestinal nematodes among post-weaned calves aged between 4 and 12 months old within a pasture-based system of south west Australia and quantify the level of anthelmintic resistance. Pre-treatment FECs were monitored on 14 dairy farms. Anthelmintic resistance was assessed on 11 of the farms. Control FECs were compared with anthelmintic FECs at 14 days post-treatment with doramectin (injectable), levamisole (oral), fenbendazole (oral) and a levamisole/abamectin combination (pour-on). Results demonstrate a strong level of anthelmintic resistance, with at least one class of anthelmintic failing to achieve a 95% reduction in FEC in one or more gastrointestinal nematode species. Doramectin was fully effective against Ostertagia, but C. oncophora displayed resistance in 91% of the farms. Conversely, levamisole was fully effective against C. oncophora, but Ostertagia displayed resistance in 80% of the farms. Fenbendazole resistance was present in both C. onocphora and Ostertagia in 64% and 70% of the farms, respectively. Trichostrongylus showed low resistance, occurring in doramectin (14%) and levamisole/abamectin combination (14%). This study confirms that anthelmintic resistance is common. Regular FEC reduction testing is recommended to monitor and guide decision-making for appropriate anthelmintic usage

A pilot study on bacterial isolates associated with purulent vaginal discharge in dairy cows in the south‐west region of Western Australia

This study aimed to determine the bacterial isolates associated with postpartum endometritis among dairy cows in Western Australia and their antimicrobial susceptibility profiles. A cross-sectional study was conducted between June–October 2020. Endometritis was defined as evidence of mucopurulent to purulent vaginal discharge 60–100 days postpartum. Vaginal discharge samples were obtained, cultured, identified and tested for antimicrobial susceptibility. A total of 118 bacterial isolates were grown from 46 animals, representing 36 species. The bacteria isolated from both aerobic and anaerobic cultures included Bacillus (60.2%), Streptococcus (12.7%), Trueperella (10.1%), Escherichia (6.7%) and Staphylococcus (5.9%). The remaining genera <5% were Histophilus, Aeroccocus, Enterococcus and Moraxella. Resistance was variable between isolates, but the highest resistance levels were observed in Streptococcal and Bacillus isolates to enrofloxacin, clindamycin and erythromycin, respectively. All Streptococcal isolates exhibited 100% resistance to enrofloxacin, and the greatest resistance levels were found in Streptococcus luteinises to trimethoprim-sulfamethoxazole 83%, clindamycin 66% and 33% quinupristin-dalfopristin. There was 84.5% resistance to clindamycin and 35.2% to erythromycin in the Bacillus isolates, with the highest resistance found in Bacillus licheniformis and Bacillus subtilis. Escherichia coli exhibited 12.5% resistance to gentamycin, ceftiofur, whereas amoxicillin-clavulanic acid exhibited 37.5%. Within the Staphylococcal isolates, 28.5%, 28.5%, 42.8% and 14.2% resistance to ceftiofur, erythromycin, cefoxitin, penicillin and tetracycline were observed, respectively. The presence of resistance to important antimicrobials for human use, such as cephalosporins, macrolides and fluoroquinolones, highlights the need for judicious use of antimicrobials in dairy cattle

The potential effects and interactions of oxidative stress and trace minerals on fresh and frozen semen in bulls - a review

Reproduction is one of the most important factors determining successful cattle farming systems. Management practices, such as nutritional supplementation, can influence the reproductive performance of cattle. The objective of this literature review is to determine the potential value of injectable trace mineral administration on fresh and cryopreserved semen quality of bulls. A search of keywords related to the topic was performed on published articles and textbooks. The search was narrowed to the 40 most relevant references. Several studies have demonstrated a positive association between trace mineral supplementation and bull semen quality. Moderate amounts of reactive oxygen species (ROS) play an important role in normal spermatogenesis, but oxidative stress (OS), as experienced with adverse environmental conditions or disease, can contribute to idiopathic male infertility by negatively impacting spermatogenesis. Trace minerals such as selenium, copper, zinc, and manganese have been demonstrated to have antioxidant effects in mammals. Due to the complexity of oral ingested trace mineral bioavailability, injectable trace mineral supplementation prior to physiological periods with known deficiencies or increased requirement can benefit the animal. The potential benefits of injectable trace mineral supplementation to minimise oxidative damage to spermatogenesis in breeding bulls need further investigation. Positive results from such studies can lead to the implementation of injectable trace mineral supplementation strategies prior to the breeding season to minimise the detrimental effects of OS and can improve semen quality.http://www.jsava.co.zaam2023Production Animal Studie

Curricular renewal at the southern tip of Africa : the ‘2016’ veterinary curriculum at the University of Pretoria

Four years after the institution of a new curriculum at the University of Pretoria's Faculty of Veterinary Science, a second major curricular renewal was initiated as a result of several pressing drivers, many of which were unique to the national and institutional context. During the project, South African higher education was disrupted by student protests prompted by financial pressures on students, the overt colonial structure of higher education, and the need to accelerate transformation of the sector. A structured curricular renewal process was followed, including the laying down of the principles, the structuring the macro-curriculum as a story, the design of a meso- and micro-curriculum, and the mapping of the curriculum to Day One outcomes. The resulting program is a 6-year bachelor's degree with a blend of discipline and species modules, with the first cohort graduating in 2016. There is a strong focus on skills embodied in a 62-week experiential component, managed using a unique custom-designed online platform for booking placements, documenting exposure, assessing competency, and providing feedback to students. The experiential training includes a large elective component. Several causes of loss of impetus during the process are discussed and proposals are made for avoiding these. The value of accreditation as a driver and a source of inputs is evident. The process has succeeded in producing a significantly reshaped curriculum that has been well received by external stakeholders.http://jvme.utpjournals.press/loi/jvme2018-09-06hj2017Production Animal Studie