10cc would be enough to worm my 3 year old buck, but not my coming 5 year old buck, in fact it is barely enough to worm my 3 oldest does

1cc per 22 pounds is the labeled dosage for using cydectin as a pour on orally, and I bet most folks do underestimate the weight of their largest bucks and does in good shape. I still use cydectin at 1cc per 25 pounds because it works for me on fecal. I use 3cc per 100 pounds orally of ivermectin plus, but I don't rely on this for anything more than the lungworm and plus controls it gives me during the winter, when our bloodsucking worms aren't working on the does. I would doubt being south of me you have any kill of blood sucking worms, other than 4th stage that Cydectin doesn't get, with using Ivermectin.
You won't find any information anywhere in Texas that tells you to rotate wormers, this is single stomached wormer info. You want to use a wormer at the correct dosage, to kill the specific worms you have on your place, until you see resistance. Hitting them with one class of wormer and then another allows both wormers to become resistant. If you don't fecal at least now and then you are flying blind. First it's super expensive to worm big animals and if you have alot of goats it's major money, it is certainly cheaper to send fecal material in to a lab (PAVL or Texas A&M) if you don't get good results (names of the worm eggs identified, numbers on a chambered slid...not just yep you got worms...from your local vet) Worm the goats, than send in another fecal to see if your wormer worked. I do two strategic wormings on my goats....before breeding and the day they kid (including the bucks) the rest of the adult wormings are about fecal rise. Even if I sent in a fecal to PAVL it would cost me $7 plus postage....that is a whole lot cheaper than worming my herd and my herd is smaller now. Getting a microscope and learning to fecal is of course one of the best things you can do for your pocketbook.
I can't do what I do with a salt block. Copper defficency is huge here. Like selenium unless all your hay and grain comes from your place, unless you know your hay guy peronally to have his address, or whre your grain is grown, it's only then that you would know what your deficeny is. Do take the opportunity when you have to put your next adult doe down to glean her liver and send in a slice to find out what is going on in your herd. Mine...I use a mineral with low iron, no red iron oxide (so the mineral is grey) it is high in copper, I take care not to use galvanized anything including pipe to the barns, so zinc is not leached into the water. No molassas which is full of iron. I bolus all incoming stock, I am also going to bolus kids this year for the first time, they simply don't eat enough minerals for me.
If you opened your gates, your goats would never choose to live in our area...they would head north! I did PM you back. Vicki