Livestock prices continued to plunge as rising feed costs prompted more selling.
The major determining factors include feed cost, availability, nutrient balance and energy density required.
Production - some animals fail to produce economic levels of milk to justify their feed costs.
Using by-products is one way of reducing the normally high feed costs.
Shares of meat producers jumped yesterday because the additional corn should reduce feed costs.
"It also placed a heavy burden on livestock, poultry and dairy producers who were faced with higher feed costs."
And their foraging skills are another thing in their favor, saving on feed costs.
Lower prices have continued into early 1993 with current profitability further squeezed owing to higher feed costs.
A champion pig breeder fears high feed costs will force him out of business within a year.
The pork industry, also facing high feed costs, remained small.