Medical doctor Michelle van Zyl says Henri van Breda's wounds were not deep enough that they required stitches, reports EWN's Shamiela Fisher.
She reiterated testimony from two other medical experts who argued that van Breda's wounds were superficial.
A forensic expert testified in the Western Cape High court last week that several of van Breda's injuries could have been self-inflicted.
The 22-year-old is accused of killing his parents and older brother and the attempted murder of his younger sister at their De Zalze home in Stellenbosch in January 2015.
Van Zyl saw the murder accused twice on 27 January 2015 at Vergelegen Mediclinic where she then worked at the Trauma Unit.
When she first treated a van Breda's wounds, she says he was talkative, jovial, friendly and showed very little emotional distress.
A hour and a half later when assessed his injuries for police evidence, van Zyl says the suspect had a more formal and calm demeanor.
The defence has argued that van Breda was given a tranquilizer, explaining his mood.
Van Zyl is the third doctor to take the stand in the van Breda murder trial, Fisher explains.
Forensic pathologist Dr Marianne Tiemensma and Dr Johan Dempers are expected to testify when the trial resumes on Tuesday.
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