PRETORIA (AFP) - Oscar Pistorius' trial for murder was adjourned on Monday after his lawyers said he was exhausted by a lack of sleep and the first day of testimony.

"Well he does look exhausted, he sounds exhausted," said Judge Thokozile Masipa, granting the defence an adjournment until Tuesday.

Earlier, the paralympian made a tearful apology to slain girlfriend Reeva Steenkamp's family when he took the stand, and a defence pathologist called key state evidence into question during the 17th day of the murder trial.

Here are the key points from Monday's proceedings:

- Pistorius turned to face Ms Steenkamp's mother June sitting in the front row of the public gallery and apologised for causing the family pain. "I was simply trying to protect Reeva," he said, "I promise that when she went to bed that night, she felt loved."

- Pistorius said he had nightmares about the shooting, sometimes struggling to sleep, and was using anti-depressants. "I've had terrible nightmares," he said. "I wake up at night smelling blood."

- Defence lawyer Barry Roux worked to paint Pistorius as a good samaritan and devout Christian. "Through this past year there have been times where I've just been struggling a lot," said Pistorius, his voice breaking. "My God's a God of refuge."

- Pistorius described his past experiences with crime, as the defence sought to portray him as feeling extremely vulnerable and in fear of intruders coming into his house. "When I grew up we were exposed to crime," said Pistorius, including "housebreakings, family members being assaulted and hijacked".

- Mr Roux outlined the defence's case, saying he will call 14 to 17 witnesses who will testify on ballistics, urine emptying, damage to the toilet door, sound, and "disability and vulnerability".

- Earlier, the first defence witness, pathologist Jan Botha, testified on the order of the shots that killed Ms Steenkamp, saying the first shot hit her hip, the second hit her arm, then bullets hit her hand and head. She was likely bending over slightly when the first shot hit her, said Dr Botha. The defence is expected to argue she was getting up after sitting to urinate when Pistorius fired.

- Dr Botha called the state's version of events into question, saying there was no certainty Ms Steenkamp was awake and ate two hours before the shooting. Analysing gastric contents "is a highly controversial and inexact science", said Dr Botha. "It could have been an hour or two, or it could have been significantly longer."

- The probable "rapid succession" of shots meant Ms Steenkamp did not have time to cry out before she died, according to Dr Botha. This contradicts a key element of the state's case, that Ms Steenkamp was screaming before she was shot by Pistorius.