Re: first year hive mites concerns
Some bees seem to be mite resistant and some are not. So which camp your bees are in will be a large part of the answer.
If your combs are built using comb foundation, then the comb between frames will be drone, because that's the main place the bees can build it. A general rulle with drone comb is that because mites prefer drone brood, if you go through some drone larvae and find no mites, the hive is likely doing well. But if you do find mites, it's a matter of how many. The often touted threshold for drone cells is an infetion rate of 25%. At that level it is believed by some you need to trake urgent action before mites overun the hive.
A way to elimnate a lot of mites from the hive, would be to clean up all the combs, scraping off any drone comb, This will remove a lot of mites. Do this several times per season. It requires no chemicals so is OK with the rulles that were made for this forum
If a hive has a very high level of mites, just drone brood sacrifice alone will likely not save the hive.
44 years, been commercial, outfits up to 4000 hives, now 120 hives and 200 nucs as a hobby, selling bees. T (mostly).