Green Parrot
Parrot infected with Beak and feather disease virus

The focus of the Veterinary Biotechnology group is to look at strategies for improved disease control, mainly in avian species, through prevention, treatment and biosecurity. Due to the improper use of antibiotics, resistance is now a growing concern. Thus, much of the current research activities has been on alternative treatment options in a post-antibiotic era. This includes work on bacteriophage therapy and the expression of bacteriophage enzymes. The expression of antibody fragments and short peptides also form part of this research drive. Recently, resistance to disinfectants has become known, jeopardising biosecurity measures. In order to overcome this, we need to understand the mechanisms of bacterial resistance to disinfectants, by studying the genome and transcriptomes of these organisms. Additional to antibiotic and disinfectant resistance, vaccine breaks often occur mainly due to the emergence of new strains or serovars, thereby impeding prevention strategies. To address this our group is looking at the development of new generation vaccines, with focus on sub-unit vaccines recombinantly expressed in our patented yeast based expression system. These vaccines are against viral and bacterial infections of avian species, including Escherichia coli, Beak and Feather disease virus, Infectious Bronchitis virus, and Avibacterium paragallinarum.

Yeast cells expressing antigens of interest
Yeast cells expressing antigens of interest

Phage plate
Agar plate showing the effects that bacteriophages can have on bacteria

Viral testing on embriotic egg
Candling of chicken eggs used for virus isolation.

Sick chicken
A chicken with infectious coryza

Avibacterium paragallinarum the causative agent of Infectious coryza in poultry has been the primary research area within our group, where we have contribute much to the literature on this pathogen. In addition to working towards the development of a recombinant sub-unit vaccine against this organism, the group is developing molecular characterisation techniques, looking at characterisation of antigens in different serovars, identifying prophages that may influence virulence, studying the genomes and proteomes of different serovars, and understanding the immunological mechanisms during the onset of disease.

Principal Investigators

Research Highlights / News


Prof Rob Bragg was an invited speaker at the International Symposium on Mycoplasma and Infectious Coryza, which was held in Amersfoort in the Netherlands in November 2019. This conference was arranged to celebrate the 100th anniversary of the GD Diergezondheid, a government funded veterinary diagnostic facility ( This symposium brought together the world leaders on both important poultry diseases. With the increasing concerns around global warming, the disease infectious coryza which was previously limited to countries in the tropics is now making its way into Europe and North America. Prof Bragg presented two talks. One was on disease control in a post antibiotic era and the second was on the difficulties in controlling the serogroup C strains of Avibacterium paragallinarum.

Nov Con Bragg

Four members of the group recently attended and presented work at the 21 World Veterinary Poultry Association Congress that was held in Bangkok, Thailand in September 2019. There were three posters presented and Prof Bragg was an invited Keynote speaker.


Recent Featured Publications

Bragg RR, Meyburgh CM, Lee J-Y and Coetzee M (2018) Potential treatment options in a post-antibiotic era. Advances in Experimental Medicine and Biology 1052: 51 – 61. Impact factor 1.760 CESM 13 Hybrid 31, DOI number: /10.1007/978-981-10-7572-8_5 Abstract

Bragg RR, Boucher CE, van der Westhuizen W, Lee, J-Y, Coetsee E, Theron C and Meyburgh L (2016) The potential use of bacteriophage therapy as a treatment option in a post-antibiotic era. Chapter 15. In Antibiotic Resistance. Mechanisms and new antimicrobial approaches. Ed K. Kon & M Rai. Elsevier. ISBN: 978-0-12-803642-6 Abstract

Boucher CE, Theron CW, Hitzeroth AC and Bragg RR (2015) Regulation of chicken immunity-related genes and host response profiles against Avibacterium paragallinarum pathogen challenge. Veterinary Immunology and Immunopathology 158;3-4 PDF

Boucher CE, Theron CW, Jansen AC, Bragg RR (2014) Transcriptional profiling of chicken immunity-related genes during infection with Avibacterium paragallinarum. Veterinary Immunology and Immunopathology, 158 (3-4). 135-142. DOI: 10.1016/j.vetimm.2013.12.004.  ISSN: 01652427. PDF

Bragg RR, Jansen A, Coetzee M,  van der Westhuizen W and Boucher C (2014) Bacterial resistance to quaternary ammonium compounds (QAC) disinfectants. Advances in Experimental Medicine and Biology 808 Pages 1 – 13. DOI: 10.1007/978-81-322-1774-9_1. Abstract


Elfrieda van den Berg (Marketing Manager)
T: +27 51 401 2531


Dilahlwane Mohono (Faculty Officer)
T: +27 58 718 5284

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