AN Ayrshire man who battered his lover's baby daughter to death while high on a cocktail of drink and drugs was yesterday jailed for life.

Allan Rennie, 29, of Main Street, Barrhill, had denied the murder of 17-month-old Karisha White in a flat in Girvan in the early hours of December 28 last year.

A jury at the High Court in Greenock rejected his claims that the baby had sustained horrific injuries in a fall down stairs and returned a unanimous verdict of guilty.

The judge, Lord Macfadyen, told Rennie: ''You have been found guilty of a dreadful murder and there is only one sentence which the law prescribes. You will go to prison for life.'' He praised the jury of 11 men and four women for the care and attention they had paid to 18 days of often harrowing evidence, and excused them from further jury service for 15 years.

The court heard that Rennie, a bricklayer, was involved in a love triangle with the child's mother Samantha, 20, and another local woman, Miss Alison Glynn,with whom he had two children.

Miss Glynn had told Rennie that her love rival was sleeping with other men and he went to the flat at Ballochtoul, Girvan, after an evening drinking vodka and lager and smoking cannabis, to confront her about the allegations.

Neighbours spoke of noisy rows lasting for much of that fateful morning and Miss White admitted that she twice left the house and was locked out, but could hear her baby crying inside.

In a bizarre twist, the court was told that her two sisters heard the furious row on an open line to the Girvan flat from their home in Shetland after the telephone was left off the hook .

They heard angry words being exchanged before Miss White left the house telling Rennie: ''You can tell Karisha why her mummy isn't here in the morning.'' Moments later in the words of one sister, Mrs Diana Taylor: ''There was a sore scream which could have lasted ten seconds, then it turned into a moaning noise. I don't think I'll ever forget that scream.''

The couple were reunited later that morning by which time Karisha was lying in her blood-soaked bed with horrific injuries. Rennie was arrested but insisted that any injuries had happened during a fall or had been inflicted by the baby's mother.

Miss White moved to the seaside town in 1995 with Karisha's father Mr Craig Moverley but he returned within months to Shetland after a series of arguments.

She met Rennie and they began an often volatile affair.

In the months before the baby's death there were conflicting reports coming from the home with some visitors saying that Karisha was bright and alert and appeared well looked after but others saying that she may be neglected.

What is in no doubt is that the blonde, brown-eyed baby girl suffered apalling injuries on the morning of her death.

Dr Jeanette McFarlane, the pathologist who examined the dead baby, said that the injuries were among the worst she had ever seen and that skull fractures ''could only be compared to the damage which might be caused if a car had driven over a child's head.'' Some jurors had to look away when shown photographs of the baby with scalded skin hanging off her face.

A story of depression and drug-taking in the life of the dead baby's mother emerged and she blamed her subtance abuse when she lost Rennie's child, which she had been carrying.

Miss White smiled yesterday as the man who killed her daughter was taken down to start a life sentence while his mother Mrs Rose Rennie and girlfriend Alison Glynn broke down in tears.