Murdered three-year-old Courtney Pieters died as a result of asphyxia through smothering or strangulation, "and/or" poisoning, the Western Cape High Court heard on Thursday.
Pathologist, Professor Johan Dempers, who supervised the toddler's post mortem, said Pieters had also sustained external blunt-force injuries to her face, torso and limbs, and that there were signs of pressure to her neck as well as genital injuries. He added that the genital injuries could have been caused by it being overextended.
When prosecutor Esmeralda Cecil asked if he could say whether she had been raped before she was killed, Dempers said he could not exclude that her injuries happened ante mortem.
Cecil also asked if it was fair to say that a penis had been used to penetrate her, pointing out the presence of semen. He responded that he couldn't exclude the scenario, but that a penis could cause the injuries she had sustained.
Accused Mortimer Saunders listened intently as Dempers testified about the results of the autopsy, which was conducted after her decomposing body was discovered in Epping Industria - nine days after her disappearance from her Elsies River home.
He faces charges of premeditated murder and rape, but denies that he planned the toddler's death or that he raped her while she was alive.
In his plea explanation, he confessed to murder and to using his fingers to penetrate her after her death.
Saunders said he had given Courtney ant poison to make her sick, before he choked her, beat her and used a towel to close her mouth.
He claimed he had done it because of "ill feelings" between him and her mother, Juanita.
Saunders - a childhood friend of Courtney's father who lived in the same house - had also apparently been irritated because the toddler wanted to watch TV in his room and he wanted to sleep.
Dempers had supervised Dr Aloysia Ogle when she conducted the autopsy. She has, however, since immigrated, resulting in Dempers taking the stand.
Both had attended the crime scene when her body was discovered during a search on May 13, 2017.
Following the initial autopsy, a second was conducted following reports of possible poisoning.
In her report, Ogle confirmed she collected specimens for toxicology, which found the presence of carbaryl in her gastric tissue, bile and blood.
Earlier in the trial, expert witness chief forensic analyst Jacobus van Zyl confirmed that more than enough poison to kill an adult was found in Pieters' blood.
According to his findings, 0.8mg/litre of carbaryl was found in her blood, but the amount could have been higher at the time of death because her remains were only recovered nine days after she died.
He explained that, depending on the dosage, the chemical could affect the flow of oxygen to the heart, slow down circulation, and also cause vomiting, tear duct secretions, excessive saliva, tremors, lack of muscle control, paralysis of the diaphragm, slurred speech, convulsions, cyanosis, coma and death.
Dempers explained that both the poisoning and the asphyxiation could, on their own, have caused Pieters' death. However, together, it could have happened quicker.
The trial resumes on August 6 to allow the defence to consult with its pathologist.