easy. i have done it more than once. give him 1,000 mill of vitamin e or fish oil capsules and  2 capsules of prostrate health complex  by trunature. all can be gotten cheaply at costco . also put him on a high protein food like eukanuba. also if he is in a kennel, you need to take him in the house and make him your pet. if he is stressed, he will loose sperm count. also put him on 500mg of tetracyclin a day for 10 days and continue with the other for life. my male lab import went from 100 million sperm count to 1 billion 100 million in two weeks doing this. i have done it with other dogs too so i know it works.