Our Management Team

John Greyvenstein

John Greyvenstein’s love for and interest in animals were the main reasons for his research into working dogs while in the process of obtaining his BSc (Zoology) (Hons) and MSc degrees in Genetics.

The subject of his thesis, “The heritability of practical important characteristics in working dogs” is an indication as to why he is regarded as a world authority in this field. Articles and papers by John are deemed brilliant by international authorities on the subject.

He is also a sought after speaker at relevant congresses and seminars. John completed several managerial and marketing courses at the University of South Africa (UNISA) and the University of Pretoria, and was a founder member of the Animal Control Research Committee of the South African Medical Services.

He was head of the dog centre of ESKOM (the South African Electricity Supply Commission), which under his leadership developed into the largest breeding and training centre for working dogs in the Southern Hemisphere at the time. John also served on the committee examining and making recommendations on the privatization of dog centres in South Africa.

He founded Bio Dog Services (now Braveheart Bio-Dog Academy) in 1987, and developed it into one of the largest private training centres for working dogs in Southern Africa, also rendering highly specialized services to international clients.

At dog training level, John is one of only a handful of A-level DH5 accredited instructors in South Africa, and is also a qualified Assessor and Moderator.

John is a past chairman of SASDA (South African Security Dogs Association), as well as past chairman of the National Dog Committee of SANSEA (South African National Security Employers Association). He is also PSIRA (Private Security Industry Regulatory Authority) representative on the SGB (Standards Generating Body) sub-committee for the generation of Unit Standards for the training of dogs and handlers in South Africa, and past Chairman of the PSIRA Dog Committee.

More achievements of John include :

The development and commercializing of the Bio-Hut and Bio Bin – a unique, patented kennel system for dogs.

John is in constant demand by governments internationally to act as Project Manager for the establishing of specialized dog training and operational centres for a variety of applications.

Since 2005, Braveheart Bio-Dog Academy has also emerged as the world leader in developing advanced training methods and aids for the detection of Narcotics and Explosives.

Marina Greyvenstein

The highly professional management team of Braveheart Bio-Dog Academy is completed by John’s wife, Marina.

Marina holds a BA degree in Social Work, and a post-graduate Diploma in Family Therapy as well as a Certificate in training method and a Diploma in Marriage Counselling.

Marina is also a qualified Assessor and Moderator.

These qualifications, coupled with a natural flair for working with dogs, make her services invaluable in integrating a private protection cum companion dog into a family unit.

John H Greyvenstein

John H GreyvensteinAs the youngest son of John and Marina Greyvenstein, the founders of Braveheart Bio-Dog Academy, John (Junior) grew up with dogs as a central part of his life.

While still at school he was already actively involved in the practical aspects of the business, and knew more about the caring for an application of working dogs at the age of 16 than most people learn in a lifetime.

John completed a course as an ambulance paramedic, joined ER24, and worked at the Charlotte Maxeke Johannesburg Academic Hospital (CMJHA) for some time.

John subsequently enrolled at the Northwest University for a BSc degree in Health Sciences. On completion of the degree, he enrolled for another BSc degree, this time in Nutrition.

After completing this degree he worked as an independent Nutritionist for some time. However, Braveheart Bio-Dog Academy had been growing in leaps and bounds, and his father (John Senior) desperately needed a 2IC who already had a firm knowledge of the field, and could seamlessly fit into the position.

As a result, John loined Braveheart Bio-Dog Academy in 2015, immediately attending a course in Social Media Marketing as the business had already firmly established an international footprint, and social media marketing had become a prime priority.

Since joining Braveheart Bio-Dog Academy, John qualified first as a Facilitator for dog and handler training, and then as a SAQA accredited Assessor (PSIRA).

He assists Dr Fanie van der Walt, head of Braveheart’s internal research laboratory in developing scientific sniffing aids for the training of sniffer dogs, and is involved in the training of sniffer dogs for detecting explosives and narcotics.

John is also responsible for specific aspects of HR management.

His “home-coming” is adding immense value to the services offered by Braveheart Bio-Dog Academy.

Mariana de Bruin

Mariana & RockyMariana decided on a secretarial career while still at school, and after finishing school obtained her Diploma in Secretarial Studies at the Upington  College.

Working for various firms over the following years, she acquired wide experience in secretarial work as well as in Management.

Mariana joined Braveheart Bio-Dog Academy in 2013 – and immediately discovered her true passion: working with dogs.

She soon acquired SAQA accreditation as an Assessor (PSIRA); as well as a Facilitator for dog and handler training.

Mariana is responsible for the registration of learners, and is involved in the training of learners in the dog and handler security industry.  She is also the contact person for private clients interested in private protection dogs and the socializing of young dogs, displaying a wide-ranging understanding not only of the industry, but also of the personal problems and preferences of prospective clients.

Mariana is the friendly, familiar, and understanding voice on the phone, the invisible but much appreciated primary client contact with Braveheart Bio-Dog Academy.

Chantal van der Linde

Chantal & KolonelChantal completed various international administrative support courses. She joined Braveheart Bio-Dog Academy in 2015.

Chantal is responsible for the smooth running of day by day administration, sup-porting compliance by Braveheart as an accredited service provider with PSIRA and SASSETA.

Chantal is intimately involved in the socialization / puppy training of young dogs; the training of  dogs for personal protection purposes; and training their “family” on how to handle their dogs.


Sam Masedi

Sam MasediSam hails from the Limpopo province.  He has been working in the dog training industry for many years – starting as an apprentice kennel cleaner, and working his way up through the ranks to become our Senior Substance Detection Dog Trainer.  He and his team of trainers have already successfully trained many Substance Detection Dogs for the detection of Explosives, Narcotics and Eco-Products in South Africa as well as abroad.  He has also participated in practical training for International Clients.

Daniel Ntobe

Daniel NtobeDaniel Ntobe has been active in the Dog and Handler training industry for a long time already.  He has intimate knowledge of Sub-Stance Detection dogs (narcotics and explosives), and boasts a wealth of experience in the training and handling of mine detection dogs (MDD) as well as narcotics detection dogs.  Daniel has worked in various African as well as other countries as a Substance Detection Dog Trainer and/or Handler, including Mozambique, Nigeria, Iran, Iraque, Syria, Afghanistan, Sudan, Ethiopia, and Somalia.


Emmie Skosana

EEmmiemmie has already been part of the Braveheart family for more than 20 years.  One of her main duties is to oversee the catering and accommodation requirements of our students.  She plays an important role in the well being and satisfaction of our students.  No army could ever march on an empty stomach.