76. Ventral dermatitis. Itchy dwarf hamster. Allergy?

A very itchy hamster.

Dwarf hamster, male, around 2 years old. Scratching ears non-stop, lower body hairless and red. Right leg, one hairless lump.

"You understand that the hamster has around 6 months of life left," the hamster bit my assistant through his fabric gloved hand when handled. He bits family members too. He pees everywhere unlike other hamsters who pees in a separate area.

My observations on Day 1 when the hamster came to the Surgery.
His cage:
He stays inside his food bowl and his sleep bowl (with tissue papers put in by the mother). "He takes the tissues and put in one right corner above the pelleted floor to sleep," the mother said.

"A new hamster costs $5.00. Veterinary charges will be more." I said.

"Should the hamster be put to sleep?" the mum asked. "I take care of the hamster. My daughter plays with him."

"New hamsters are free of charge," the mum replied.

"However, the younger generation will not want their pets to be put to sleep. Ask her."
The girl shook her head. So, the mum decided to get the hamster treated. I warded him for 4 days.

History
"Could he be suffering from allergy? His mother who lived separately had same red hairless lower body and itchiness. Vet 1 diagnosed allergy. The mother had died recently.

Any changes of the environment?
1. New litter in December 2009 - grey pelleted ones as the pet shop had stopped selling the white cottony litter which was used previously. Itchiness started for the mother and the son.

"Why don't you buy the coloured ones?" I asked. The owner did not like the coloured ones and so bought the grey pellets.

2. New sand bath in December 2009 too. No more sand bath for some weeks.

From the history, this seemed to be contact or ventral dermatitis due to irritation of the litter.

Treatment
Avoidance of irritating litter, sand and prevention of the hamster squatting inside the food bowl. I used a flat small food bowl. Wait and see for the next few days. On Day 2, I observed considerable less scratching and took some pictures.