[Pamela L]

Here is the answer for affordable heartworm control. I use the 1% injectable for Cows. You can get it at almost any feed store for about $25. It does not taste good to the dogs but I can treat the animials in my no-kill shelter for about $25 per year which is amaziing. Here is the dosage:

Directions for making 30:1 dilution of 1% solution
A 30:1 dilution works best for smaller dogs. Ivemectin is given orally (never use pour-on solutions for heartworm prevention).

Mix 30 parts glycerin, propylene glycol, or vegetable oil to 1 part ivermectin 1% solution. Shake well before using to mix the ivermectin evenly. Refrigerate any unused portion (do not store mixtures with vegetable oil).

Dosage using Ivermectin 1% solution at 30:1 dilution for heartworm prevention (you may want to double these doses for better protection):
< 6 pounds: 0.05 cc (one-half of 0.1 cc, or 1 drop from an eye dropper, assuming 20 drops per ml)
6 to 12 pounds: 0.1 cc
13 to 24 pounds: 0.2 cc
25 to 36 pounds: 0.3 cc
37 to 48 pounds: 0.4 cc
49 to 60 pounds: 0.5 cc
62 to 72 pounds: 0.6 cc
73 to 84 pounds: 0.7 cc
85 to 97 pounds: 0.8 cc
98 to 109 pounds: 0.9 cc
110 to 121 pounds: 1 cc
Ivermectin solution is given orally. It’s best to squirt it into the mouth, rather than adding to food, to be sure your dog gets it all.

To make a small amount of the mixture, you will need a 1 cc syringe that measures accurately to the tenth of a cc. Draw up 0.1 cc of Ivermectin solution in a 1 cc syringe, and mix well with 3 cc of glycerin, propylene glycol, or vegetable oil, giving you 3 ccs at a dilution ratio of 30:1. This is enough to treat 300 pounds of dogs using the 1% solution.

To make larger amounts of the mixture, use a 1 fluid ounce dropper bottle, which is 30 ml. Put 1 ml of ivermectin solution in a 1 fluid ounce dropper bottle, then fill with glycerin, propylene glycol, or vegetable oil. This will be enough to treat 3,000 pounds of dogs (e.g., 300 10-lb dogs or 150 20-lb dogs) using the 1% solution.

1 cc of ivermectin 1% diluted 30:1 contains 333 mcg; 0.1 cc = 33 mcg.
The exact dosage is 0.0824 cc (approximately 0.1 cc) per 10 pounds of body weight.

Directions for making 9:1 dilution of 1% solution
A 9:1 dilution works best for larger dogs. Ivemectin is given orally (never use pour-on solutions for heartworm prevention).

Mix 9 parts glycerin, propylene glycol, or vegetable oil to 1 part ivermectin 1% solution. Shake well before using to mix the ivermectin evenly. Refrigerate any unused portion (do not store mixtures with vegetable oil).

Dosage using Ivermectin 1% solution at 9:1 dilution for heartworm prevention (you may want to double these doses for better protection):
up to 18 pounds: 0.05 cc (one-half of 0.1 cc, or 1 drop from an eye dropper, assuming 20 drops per ml)
19 to 36 pounds: 0.1 cc
37 to 73 pounds: 0.2 cc
74 to 110 pounds: 0.3 cc
111 to 147 pounds: 0.4 cc
Ivermectin solution is given orally. It’s best to squirt it into the mouth, rather than adding to food, to be sure your dog gets it all.

To make a small amount of the mixture, you will need a 1 cc syringe that measures accurately to the tenth of a cc or a dropper bottle. Draw up 0.1 cc of Ivermectin solution in a 1 cc syringe, and mix well with 0.9 cc of glycerin, propylene glycol, or vegetable oil, giving you 1 cc at a dilution ratio of 9:1. This is enough to treat 333 pounds of dogs using the 1% solution.

To make larger amounts of the mixture, use a 1 fluid ounce dropper bottle, which is 30 ml. Put 3 ml of ivermectin solution in a 1 fluid ounce dropper bottle, then fill with glycerin, propylene glycol, or vegetable oil. This will be enough to treat 9,000 pounds of dogs (e.g., 90 100-lb dogs) using the 1% solution.

1 cc of ivermectin 1% diluted 9:1 contains 1,000 mcg; 0.1 cc = 100 mcg ivermectin.
The exact dosage is 0.0272 ml (approximately 0.03 cc) per 10 pounds of body weight.