Fish and prawns are extremely efficient in converting feed into high-quality proteins.
In fact, fish are the most efficient animals to produce, since the feed conversion rate or FCR is very low (the amount of feed an animal needs to gain a kilogram of body weight). On average, farmed fish need 1.1 kg of feed to gain 1 kg of body mass, compared with 1.7 kg for poultry and 6.6 kg for livestock.
Through a comprehensive understanding of specific nutritional needs, Atlantic salmon is currently the most efficient animal to produce, with the lowest FCR. Normally, this species needs 1.15 kg of feed to gain 1 kg of body weight. Pigs need more than twice as much feed as salmon to earn 1 kg, while sheep need to eat almost six times more.
Fish also has a high crop yield in comparison to other farm animals. Crop yield is the percentage of the animal that remains after removing the inedible parts. For example, Atlantic salmon has a total yield of 86%. In comparison, chicken has a crop yield of only 47%.