After giving the cow six weeks to rear the calf, he contacted a transporter to take the cow, along with other cattle, to the meat works.
He completed an animal status form but did not complete a pre-transport form, which holds a minimum standard whereby animals must not be transported if they display injury or disease that could compromise their welfare during the journey.
A veterinarian inspecting cattle at the meat works immediately deemed Cow 10 a "suspect" animal, unfit for human consumption, due to a bleeding eye lesion later identified as cancer eye with spread to lymph nodes in the head.
The entire carcass was condemned and an expert pathology report affirmed the tumour had likely been present for months and would be "significantly painful" due to the involvement of the bone and tissues around the blinded eye.
McGhie admitted he didn't obtain a pre-transport veterinary certificate and that even if he had called a professional he knew they would have likely told him to euthanise her immediately.
Defence counsel Leo Lafferty told the court his client accepted culpability but that the situation was vastly removed from that of a beating or deprivation of health and welfare.
The nature of cancer meant it could move swiftly and the farmer had not noticed any weight loss which was a key symptom of disease, he said.
Judge Bridget Mackintosh said while McGhie didn't know the cow had cancer eye, he had been aware something was wrong for some time.
The farmer had thought insofar as his farming practice was concerned that he was able to obtain some recompense in the carcass, she said.
However the judge acknowledged his remorse and excellent character references from within the meat industry, accepting animals often don't show the pain they are feeling.
She said the case highlighted issues of animal welfare and the importance of keeping a close eye on things and taking action sooner rather than later.
Hawke's Bay Federated Farmers president Will Foley said it wasn't common practice to ignore an issue for so long, and actually made economical sense to call a vet as cattle could be worth a lot of money.
"Generally farmers are pretty cautious and will get onto a vet pretty early because cattle beasts could be worth $1500-$2000. It pays to get on to it straight away."
Mr Foley said the sentencing outcome was a good result and sent a strong message that such treatment of animals wasn't tolerated.
He was fined $2500 for the treatment and transport charges, along with $423.25 for expert pathology and court costs.
Animal welfare charges carry a maximum penalties of 12 months' imprisonment and a fine of $50,000.
McGhie could not be reached for comment.