Grain-to-meat ratios for farm animals are the amount of feed required to produce a pound of meat. These ratios are calculated on the amount of feed fed from a sack or bulk container and do not normally include grazed forage, mast (nuts and berries) or insects. Grain-to-meat ratios, a measure of feed efficiency, is watched very closely by the stockman and poultry producer because good feed efficiency helps increase profits. Grain-to-meat ratios are often referred to as feed conversion ratios (FCR).
Variance Among Species
Grain-to-meat ratios are different for each species of animal. Some are more efficient than others. It takes about 3.5 lbs. of feed to produce 1 lb. of weight gain in pigs. Broiler chickens on the average require 1.8 lbs. of feed to produce 1 lb. of gain and laying hens need 2.0 lbs. Salmon are the most feed-efficient with a 1-to-1 ratio. Beef cattle, partially because of their size, use 6 lbs. of feed to produce 1 lb. of weight gain.
Feed conversion ratios are affected by the type of animal management. The Ontario Agriculture, Food and Rural Affairs substantiated this when it set FCR targets for lambs. It set a feed conversion target of 6.0 to 8.5 lbs. of feed per pound of gain for grass-fed lambs introduced to a grain diet. For lambs fed grain from weaning to a market weight of 80 lbs., the target feed conversion is 3.0 to 4.0 lbs. of feed for 1 lb. of gain. If the lambs are fed to a market weight of 85 to 100 lbs., the target feed conversion is 5.0 to 7.0 lbs. of feed to 1 lb. of gain.
Type of Feed Influence
Certain types of feed are more easily converted to meat than others. This was confirmed in research tests conducted by The Samuel Roberts Noble Foundation and reported by Ryan Reuter. Cattle fed dried corn distillers grain had a 4.2-to-1.0 feed conversion ratio, whereas cattle fed soybean hulls had a 5.6-to-1.0 ratio. The results of this test show that corn distillers grain is more readily converted to meat than soybean hulls.
Feed Conversion Significance
Feed is one of the most costly inputs in meat production, whether it be poultry, beef, pork or lamb. So it is to the producer's benefit to watch feed conversion ratios carefully. Every time he can get more meat from a pound of feed, his cost/income ratio improves. Good feed conversions are so important that they are one of the traits considered in breeding program design.