A girl who soiled herself was made to kneel in scalding water by her foster mother, a family court judge has concluded.
The youngster, now 12, had also been seen picking up faeces in the garden of her Lancashire home, Judge Sarah Singleton said.
She also told how she had been bitten by her foster parents' Rottweiler dogs.
Judge Singleton said the youngster had been left physically scarred and "deeply traumatised".
The judge said the girl's foster mother and father - a lorry driver - were responsible for "emotional abuse and neglect".
Neighbours and school staff had been concerned, police and social workers had been involved and opportunities to protect had been missed, said the judge.
She said she was concerned about the "quality and superficiality" of an assessment carried out by social services staff at Lancashire County Council.
The judge said the girl had lived with the couple for about a decade and was now in the care of Lancashire council.
Detail has emerged in a ruling by the judge following a private hearing at a Blackpool family court.
The judge said she had been asked to make decisions about who had caused harm to help social workers plan for the youngster's future.
She said the girl could not be identified.
The foster parents were not named - and the ruling gave no indication as to whether they had been charged with criminal offences.
Judge Singleton said the youngster had been born in Luton, Bedfordshire, and had also lived in Yorkshire. The foster parents had lived near Scarborough before moving to a new home near Blackpool.
She said the youngster's mother was a black Zimbabwean asylum-seeker.
The woman had placed her daughter with the couple, who were British and white, under an "informal fostering arrangement".
A residence order had been made at a county court in York 10 years ago, said the judge.
Judge Singleton said the girl had been treated with "cold contempt" by her foster parents, who kept animals including three Rottweilers, at least one cat and a "large" pig.
The judge said evidence showed that the animals were "well cared for".
She said the foster mother had demonstrated more warmth for the animals than the girl when giving evidence at the court hearing.
Judge Singleton said the couple's approach to the girl's soiling problem had been "very cruel".
The girl had told how she had been "shut outside".
Her scalding injuries were probably linked to "somebody's disgust and vituperation over the soiling accidents" and connected to an "abusive method" of "forcing her to clean herself up", said the judge.
She said it was "very hard to contemplate" that the girl had been deliberately scalded.
The foster mother had also repeated the "highly-offensive 'N' word" with "alarming facility" when giving evidence, said the judge.
And the foster father had described the little girl as "strange and disturbed" - adding: "Maybe it was because she was African."
The couple had dealt with her racial identity "insensitively", said the judge.
Judge Singleton outlined concerns raised at schools - including concerns that the girl was not getting enough to eat - and the involvement of police and social workers over a number of years.
She said the girl had been taken from the foster couple and into council care about two years ago after making complaints about her foster mother's "cruelty and abuse" during sessions with a counsellor organised through a school.
The judge gave detail of instances of where she thought that opportunities to protect the child had been missed.
She outlined a concern about the quality of an assessment carried out by Lancashire County Council Social Services five years ago. She said she was sure that her concerns would be "looked into".
"So far as the very serious thermal injuries to this child's legs and buttocks, it seems to me that they are likely to have been caused by her kneeling down, thighs on buttocks, or being made to kneel down in that position in very hot water or liquid," said Judge Singleton.
"Those thermal injuries, it seems to me, were either deliberately inflicted by (the girl) being made to kneel in very hot liquid, or they were accidental when somebody had forced her to clean herself in very hot liquid. If they were accidental, they constitute gross negligence, both in allowing the injuries to occur in the first place, but more particularly, in not seeking treatment for those injuries."
There were "repeated references" in school records to (the girl) "hiding her legs", said the judge.
The foster mother had insisted on the girl not being examined by a school nurse without her being there and had insisted on the girl's legs being covered during a school production.
"It seems to me that this behaviour is likely to be coincident with the appearance of those injuries," said the judge.
"On balance, therefore, having looked at those injuries, it seems to me more likely than not that they were deliberately caused by her being forced to kneel down."
She added: "The child was hiding her legs at school with the connivance of (the foster mother)."
The judge went on: "This child has not yet said what happened to her legs. However, by her account there was a very cruel approach in this household to her soiling problem. On her account, when she demonstrated that soiling problem, she was either shut outside or made to sleep on the landing...
"On balance ... and it is very hard to contemplate, I do consider that those scalding injuries were deliberately inflicted. They were probably linked with somebody's disgust and vituperation over the soiling accidents and were likely to be linked with an abusive method of cleaning her up or forcing her to clean herself up."
Judge Singleton said the "pool of possible perpetrators" was "plainly limited" to the foster mother and foster father.
"I have concluded firmly that the likely perpetrator is (the foster mother)," said the judge. "(The girl) has been wholly consistent in saying that the perpetrator of injuries against her was (the foster mother)."
The judge added: "Both of these people, (the foster mother) and (the foster father), are responsible for emotional neglect and abuse.
"They did not allow this child to have or promote her to have a positive self-image.
"They did not deal with her soiling problem and no doubt related to that unsympathetically.
"They each treated her with cold contempt, which also emerged during the course of their evidence.
"They dealt with her racial identity insensitively - or, frankly, they did not deal with her racial identity at all."
Judge Singleton said Lancashire council had asked her to make decisions about the cause of the girl's injuries.
And she said council lawyers had argued that the couple had allowed their three Rottweiler dogs to frighten and bite the youngster.
The judge concluded that the girl had been bitten by the dogs.
"So far as the dog bites are concerned that (the girl) alleges, I do think it likely that some of her injuries have been caused by dog bites," said the judge.
"I do not think it likely that the three Rottweilers were deliberately set upon her to attack her, but I do think it likely that she was frightened of the dogs, that in their presence she was treated, by (the foster mother) particularly, to being shouted at and to contemptuous treatment that might well cause a dog from time to time to nip her and bite her because that is what the dogs would perceive (the foster mother) or (the foster father) to be doing to her.
"The fact is that if dogs of this size and type were actually set upon somebody to attack, the injuries that would be seen would be far worse than are seen.
"I do consider it likely that the dogs have from time to time bitten her. Certainly she was frightened of them. That fear was observed by others and both carers should have been aware of it and monitored the situation more carefully."
Judge Singleton outlined evidence given by two neighbours - in Lancashire - about an incident in the summer of 2010, when the girl was aged about eight.
"(They) reported what they perceived to be ill-treatment of (the girl) observed from the next door property to the family home, to the police," said the judge.
"(One neighbour) was so concerned by what she saw ... that ... she ... wrote her own notes about it and kept them in her Filofax.
"She eventually assumed that nothing was to be done and destroyed those notes some two years later.
"She struck me as entirely respectable and completely independent and she was doing her best to tell me accurately and without overstatement what she remembered."
The judge added: "(That neighbour) used to look into the garden ..., initially very interested in the large pig she could see...
"One particular day she noticed (the girl) whom she had seen out with (the foster mother) and (the foster father) and their dogs on other occasions.
"She noticed her on this occasion because (the girl) was standing unnaturally still in full sunshine.
"(The girl) did not move or play.
"(She) saw (the foster mother) come out with a plate of sandwiches which (she) assumed were to be for the child, but in fact they were given to the pig, and (the foster mother) spoke harshly to (the girl).
"Shortly after that, (the girl) started to shift about and cross her legs. (That neighbour) assumed that she needed the toilet, and indeed shortly thereafter the child plainly wet herself.
"(The foster mother) again emerged from the house, but this time shouted at the child. She seemed to make her remove and fold each item of clothing that she was wearing and made her peg her dress on the washing line.
"She called her, so far as (that neighbour) could hear, a 'dirty little bitch' and said that (the girl) would have to wear that dress 'tomorrow'.
"(That neighbour) tried and failed to take a photograph on her phone of what she was observing, but could not do so because the phone was new to her and she could not operate the camera controls.
"The child was then left outside naked until (the foster mother) harshly called her in. (The girl) had to go back out again for her shoes.
"(That neighbour) reported the matter to the police.
The judge added: "On another occasion, (that neighbour) had observed (the girl) picking up faeces in the garden which she, perhaps not unreasonably, thought were dog faeces.
"She also observed (the girl) surrounded by the Rottweilers and had the impression that she flinched.
"Overall, she was disturbed by how cold (the foster mother) was to the child."
Judge Singleton said both neighbours had been prepared to give evidence to social services staff and police.
"Social services undertook a core assessment after these allegations were made but they never attended and spoke with these witnesses," said the judge.
"Although the police came and took statements, they never came back with a typed copy to be signed and processed."
The judge said she thought both neighbours were "truthful" witnesses.
She outlined concerns about an assessment carried out by Lancashire council's social services department.
"The assessment by Lancashire County Council Social Services in August 2010 concluded that there was no supporting evidence for the concerns about (the girl), and they determined that it was appropriate to take no further action," said the judge.
"I am concerned about the quality and superficiality of that assessment."
She added: "I am sure it will be looked into."
Judge Singleton analysed the case earlier this year but her ruling has only recently been published on a legal website.