What are these crusty, circular sores on my 8-week lab puppy's snout?

I would be very suspicious that may be a ring worm or a bacterial infection. She needs to be checked by a vet because a ring worm can be contagious to people and other animals. You vet can take a sample and culture it to see the cause. Until you can get seen you can apply Neosporin topically

It sounds like Charlie needs to be examined by the veterinarian. Those spots and the lesions on the muzzle could be several things including ringworm (which humans can get) allergies to something in the environment, food allergy or endocrine disease. Each one of these problems is detected and addressed differently and I recommend to discuss with your veterinarian which one to start hunting down first. Ringworm is diagnosed at the vet's office by examined the hairs. Food allergy is best ruled out with a diet trial using a hydrolyzed protein. Endocrine diseases are detected with blood work. Environmental allergies are a little more difficult to detect but a response to therapy or a blood test can give an indication. Once you figure out and address the underlying cause, the lesions should not come back. There are a couple things you can do at home and they can help but they may not address the underlying cause. You can try adding in an omega 3 fatty acid supplement for dogs, this can help improve the skin health. You may also try changing his diet to something like Royal Canin or Nutro as they are aimed at skin health. Also protect the area from trauma by having Charlie wear an elizabethan collar at all times if he is trying to lick or scratch the lesions. Best of luck and please feel free to post any additional questions.

Poor Emmitt! The lesions on his leg and muzzle could be due a bacterial skin infection (often from underlying allergies), ringworm, or mange. Make sure that he is receiving a high quality flea preventative regularly, such as Nexgard, Bravecto, or K9 Advantix II since flea allergies can lead to itching and subsequent skin infections. You can also try bathing Emmitt in an antimicrobial shampoo ( http://www.drsfostersmith.com/product/prod_display.cfm?pcatid=27982 ), but use caution around his face and be sure to rinse and dry well. Also consider switching to stainless steel bowls rather than plastic or ceramic bowls if you aren't already using them in case the lesions on his face are related to an "acne-like" condition. Stainless steel is less porous than the other materials and tends to harbor less bacteria. If these skin lesions persist or worsen, Emmitt will need to take a trip to his vet for further evaluation. I hope that all goes well!

The lesion on Luna's face may be a bacterial infection, a fungal infection known as ringworm or due to a skin mite known as Demodex. Luna will need to see a veterinarian for an exam and a skin scrape to determine the correct diagnosis. Treatment is very different for each condition and they can all look similar, so testing needs to be done to be sure.

The lesion on Chance's face could be due to ringworm, mange, or a bacterial skin infection. The only way to differentiate between these conditions is with diagnostic testing. Since ringworm and one type of mange (Sarcoptic mange) are contagious to people and other pets, I recommend taking Chance to his vet. The vet will be able to perform a fungal culture (to check for ringworm), a skin scrape (to look for the mites causing mange), and a skin cytology (to look for bacteria). From there, medication can be started. I hope that all goes well!

These types of lesions are normally seen with a skin infection, but ringworm does not typically look like this. The fact that she has been licking more may be the reason for her developing a skin infection of her muzzle. These infections often develop when there is excessive moisture, or when something is irritating the muzzle. This can happen when their mouth has contact with a plant, or substance that irritates the skin. These type of infections are usually managed well at home with daily cleaning. I recommend rinsing the are with cool water, then wiping it with a medicated wipe (can get this at the pet store). It's best if you can do this twice a day. If the lesions are not starting to heal after a week of treatment, or are getting worse, then I recommend taking her to the vet. The vet will be able to diagnose the specific cause of this and provide the best treatment. I hope that helps and Little Bear gets better soon.

From the picture, I'm concerned that doesn't look like ringworm to me. It looks like it could be a growth or an ulcerated area. It looks pretty red and sore in the picture, and unfortunately without seeing Chloe in person, I can't say for certain what it is. I would take her into a vet to get this diagnosed and treated, try to have her seen by her vet in the next few days. I hope this helps!