The Onderstepoort Journal of Veterinary Research (OJVR), is the official publication of the Onderstepoort Veterinary Institute. It publishes scientific papers reporting original research on diseases and disease vectors of livestock and wildlife with a focus on Africa, but with results of more than local interest.

Background: Brucellosis is an infectious and contagious zoonotic bacterial disease of both humans and animals. In developing countries where brucellosis is endemic, baseline data on the prevalence of brucellosis, using abattoir facilities, is important.Objectives: The aim of this study was to determine the seroprevalence of antibodies against Brucella in slaughter cattle at Gauteng province, South Africa and to characterize isolates of Brucella spp.Methods: In this cross‐sectional study, un‐clotted blood samples with corresponding organ tissue samples were collected from slaughtered cattle. Serological [Rose Bengal test (RBT), complement fixation test (CFT) and indirect ELISA (iELISA)], molecular (PCR) and bacteriological methods were used to detect Brucella antibodies and Brucella spp. from 200 slaughtered cattle in 14 abattoirs.Results: The RBT revealed a seroprevalence of brucellosis as 11.0% (22 of 200) and iELISA confirmed 5.5% (11 of 200). The estimated seroprevalence from RBT and iELISA was 5.5% while RBT and CFT was 2.0% (4 of 200). Brucella melitensis (n = 6) and B. abortus (n = 5) were isolated from 11 cattle tissues (5.5%) as confirmed to species level with AMOS PCR and differentiated from vaccine strains with Bruce‐ladder PCR. Seven of the 11 isolates originated from seropositive cattle of which five were biotyped as B. abortus bv 1 (n = 2) and B. melitensis bv 2 (n = 1) and B. melitensis bv 3 (n = 2).Conclusions: This is the first documentation of B. melitensis in cattle in South Africa. The zoonotic risk of brucellosis posed by Brucella‐infected slaughter cattle to abattoir workers and consumers of improperly cooked beef cannot be ignored.

Consumption of food that is contaminated by microorganisms, chemicals, and toxins may lead to significant morbidity and mortality, which has negative socioeconomic and public health implications. Monitoring and surveillance of microbial diversity along the food value chain is a key component for hazard identification and evaluation of potential pathogen risks from farm to the consumer. The aim of this study was to determine the microbial diversity in meat and meat products from different enterprises and meat types in South Africa. Samples (n = 2017) were analyzed for Yersinia enterocolitica, Salmonella species, Listeria monocytogenes, Campylobacter jejuni, Campylobacter coli, Staphylococcus aureus, Clostridium perfringens, Bacillus cereus, and Clostridium botulinum using culture-based methods. PCR was used for confirmation of selected pathogens. Of the 2017 samples analyzed, microbial ecology was assessed for selected subsamples where next generation sequencing had been conducted, followed by the application of computational methods to reconstruct individual genomes from the respective sample (metagenomics). With the exception of Clostridium botulinum, selective culture-dependent methods revealed that samples were contaminated with at least one of the tested foodborne pathogens. The data from metagenomics analysis revealed the presence of diverse bacteria, viruses, and fungi. The analyses provide evidence of diverse and highly variable microbial communities in products of animal origin, which is important for food safety, food labeling, biosecurity, and shelf life limiting spoilage by microorganisms.

Retrospective laboratory-based surveillance was conducted on Salmonella serotypes isolated from various animal species from 2007 to 2014 at the Agricultural Research Council, Onderstepoort Veterinary Research Institute, South Africa. During the surveillance period, 1229 salmonellae isolations were recorded. Around 108 different serotypes were recovered from nine different food and non-food animal host species. The three most common serotypes were Salmonella entericasubspecies enterica serotype Heidelberg (n = 200), Salmonella enterica subspecies enterica serotype Enteritidis (n = 170) and Salmonella enterica subspecies enterica serotype Typhimurium (n = 146). These were followed by Salmonella enterica subspecies enterica serotype Anatum (n = 62) and Salmonella entericasubspecies enterica serotype Infantis (n = 57). Salmonella enterica subspecies enterica serotype Schwarzengrund and Salmonella enterica subspecies entericaserotype Muenchen were recovered in 50 and 48 cases, respectively. Of the total number of isolations recorded during the period under review, 871 (70.8%) occurred in poultry and other birds, 162 (13.2%) in horses, 116 (9.4%) in cattle, 26 (2.1%) in sheep and goats, 22 (1.8%) in rhinoceroses, 16 (1.3%) in pigs, 8 (0.6%) in crocodiles, 6 (0.5%) in cats and 6 (0.5%) in leopards. Food animals accounted for 83.5% of the total isolations, with cattle and poultry representing approximately 72.7%. Forty-two (3.4 %) isolates were found from non-food animals that include rhinoceroses (n = 22), crocodiles (n = 8), leopards (n = 6) and cats (n = 6). Salmonella Heidelberg was the most frequently isolated serotype, whereas S. Typhimurium had the widest zoological distribution. Clinical laboratory isolation of different Salmonella serotypes from various hosts may aid in recognising the threat to livestock, public and environmental health. Moreover, it may also highlight the potential zoonotic and food safety risk implications of the detected Salmonella serotypes.

Background: Brucellosis is an infectious zoonotic bacterial disease of humans and other animals. In the Republic of South Africa (RSA), animal brucellosis is widespread and the current available data on the prevalence of this disease rely solely on serological testing. The primary limitation of brucellosis serology is the lack of discriminatory powers to differentiate between Brucella species and biovars as well as the cross‐reactivity observed with other Gram‐negative bacteria.Aim: The aim of this study was to conduct a retrospective laboratory‐based survey on Brucella species and biovars isolated from various animal species in SA between 2008 and 2018.Material and Methods: The isolation of Brucella species and biovar typing was performed using conventional microbiological techniques.Results and Discussion: A total of 963 strains of Brucella species were included in this study with a frequency of detection for B. abortus (n = 883; 91.6%) followed by B. melitensis (n = 42; 4.4%), B. ovis (n = 29; 3.0%) and B. canis (n = 9; 0.9%). Of the 883 strains of B. abortus, 90.1% were typed as B. abortus biovar‐1 while 5.7% as B. abortus biovar‐2, and 3.3% and 0.5% were B. abortus S19 and B. abortus RB51 vaccine strains, respectively. Among the 42 B. melitensis strains, 71.4% were reported as B. melitensis biovar‐1 and 26.2% as B. melitensis biovar‐3 while 2.4% was B. melitensis biovar‐2.Conclusion: A retrospective study, such as this one, provides useful information that can be critical in formulating policies and strategies for the control and eradication of brucellosis in animal populations in RSA.