Asking a supplier the right questions

As in every industry, manufacturers from all kinds of products will try to convince pig producers to buy their products. Now what would be a suitable strategy for pig producers to figure out which product is good for their farm? Expert contributor John Gadd is presents a road map. I have a problem. It is preventing me in many cases from giving accurate advice to my clients. Frustrating, because manufacturers and sellers are not giving me the information on their products, which I need to make co