A man was sickened when he found a dead mouse in his loaf of bread while making sandwiches for his children.
The father-of-two thought the bread was just discoloured but on closer inspection saw the object was covered in fur.
Stephen Forse, from Kidlington, Oxfordshire, bought the Hovis Best of Both bread online from Tesco, through a store in Bicester, in January 2009.
Mr Forse said yesterday: "I noticed a dark coloured object embedded in the corner of three or four slices.
"Initially I thought it was where the dough had not mixed properly prior to baking. As I looked closer I saw that the object had fur on it.
Mr Forse continued to prepare some sandwiches for his children from another loaf of bread, checking each slice carefully.
He said: "I still felt quite shaken. As I was feeling ill I couldn't face eating anything myself."
The experience was only made worse when environmental health officers visited the family's home to collect evidence and found the mouse was missing its tail.
Mr Forse said: "Her comments made me feel ill once again as there was no indication as to where the tail was.
"Had it fallen off prior to the bread being wrapped or had any of my family eaten it with another slice of bread on a previous day?"
Following an investigation by council health officers, Premier Foods was ordered to pay £16,821 at Oxford Crown Court on Friday.
Premier Foods pleaded guilty to failing to ensure all stages of food production were protected against contamination and failing to maintain a robust pest management system at its British Bakeries site in Mitcham, south London.
Cherwell District Council technical officer Aileen Smith said: "Mice harbour disease, particularly salmonella which can result in severe diarrhoea, vomiting, fever and can be fatal to children, the elderly or those with a compromised immune system."
A Premier Foods spokesman said: "We apologise profusely for the distress caused as a result of this isolated incident."