Small bald spot??

This just  happened to our puppy.  Small bald patches the size of a pea started showing up.   The vet found no demodex but is treating her for it anyway. SHe got 1 dose of ivermectin every week for 4 weeks.  You have to kill the entire life cycle of the mite.  She alos gets a weekly bath in special peroxide vet shampoo follwed by a tea tree oil / lavender rinse.
 
Her diet is of utmost importance and the spaying is critical to stop the body from wreaking havoc on itself allowing the resident mites to take hold.  Heat  cycle triggers bad demodex .  I read a high meat diet is essential along with extra vitamins and immune boosters like colestrum and echanacia and DMG.   I feed lots of meat, raw, cooked or Nature Variety patties, canned salmon, eggs, canned EVO and very little dry kibble.  
 
You are lucky the mites showed up under the scope.  You should Google "demodex" to get a handle on this.   As the others said, it is triggered by stress, vaccines and heat cycles.  Apparently all dogs have it but only certain ones get an outbreak like yours and mine.  My puppy is a bulldog which are prone to it.
 
CallieCrittur has a great doc on how to treat it,,you could email her for it.

THank you for all the information.  She is getting spayed on the 5th so that will be good then.  I wish she would have been spayed sooner but I had to take the date they gave me.  Then with Rabies I think shes good for three years with the ones they give in Ohio.  Either that or she gets one more this year and then is good for three years.  December 5th will not get here soon enough for me now.  I worry so much about her going into heat PLUS the place that is going to fix her will charge me $25 to $55 extra if shes in heat.....grrrrr.  Would have been nice if they fixed her when I called when she was much younger.
Im getting some of that shampoo.  I found it online with shipping for about $13.  Then I still have the meds for two more weeks.
Ill keep an eye on her for sure.  Thanks again everyone.......