Hello. Thank you for asking your question on just answer. My name isXXXXX will try to help.
The bump that you squeezed is a blocked oil gland. It is sort of like a giant "pimple." They are very common in dogs. It will occasionally fill up and then drain with the thick white, or tan, pus. The only way to get rid of it is to have ti surgically removed. If it is not bothering her then I would just monitor it.
If it was a cuterebra, and you squeezed it out, a large larvae, about an inch in size, would come out.
Flies, or other insects do not lay eggs in dogs.
If the flies laid maggots, it would look like squirming rice sized worms.
If both dogs are itching, it fleas.
It would be very unusual for two dogs to develop allergies at the same time.
I would treat both dogs with "frontline drops" or "advantage drops." You can get both online, or at the pet store, with out a prescription.
You can give them benadryl for itching. The dose is 1 mg per pound every 12 hours. So, a 10 pound dog would get 10 mg of benadryl every 12 hours.
You can also spray hydrocortisone spray on the itchy spots every few hours.
If you are 100% sure it is not fleas, which I think it is, it could be food allergies, environmental allergies, mange, or ringworm.
To determine if it is food allergy the patient is put on a hypo allergenic diet (hills z/d) for 4-6 weeks. During this time you can not give any other food or treats. Doing so will ruin the test. After 4-6 weeks the patient is put back on the regular diet. If the skin flares up again you know food allergens are the cause of the skin problems.
www.veterinarypartner.com/Content.plx?P=A&A=652 food allergy
www.veterinarypartner.com/Content.plx?P=A&A=468 food allergy
Atopy is when the patient has become allergic to normal substances such as pollen, mold, and dust mites. The symptoms can be controlled and prevented but it can not be cured. There is a blood test that can be done to see what she is allergic to. If desired she can be given allergy shots to hyposensitize her to the allergens. The allergy shots are 50-75% affective.
Ringworm is a type of fungus that causes circular patches of hair to fall out. Sometimes it can make large areas of hair fall out. You will need to go to your vet to get this one diagnosed. Your vet will pluck some hairs from an affected are and culture the hairs to see if there is any fungal growth.
There are two types of mange. Demodex and Sarcoptes. They are microscopic parasites that attack the hair follicles. This will also have to be diagnosed by a veterinarian. You can read more about each below.
www.veterinarypartner.com/Content.plx?P=A&A=599 itch relief for more remedies