Livestock
The role of animal nutrition in sustainable and healthy food systems
�e requirement of humans for protein represents on average 10 – 35 % of the daily caloric intake. According to the Dietary Reference Intakes( DRIs) issued by the Institute of Medicine of the US Food and Nutrition Board, 1 adults need to eat about 60 grams of protein per day. Protein is mainly found in meats from poultry, pork and beef, in sh, eggs and dairy products( cheese and milk), but also in vegetable sources such as legumes( soya, beans), grains, nuts and seeds, and also in certain vegetables. Protein that comes from animal sources is in general nutritionally more complete, because it contains the essential amino acids in a more adequate pattern than is the case with plant proteins.
Poultry meat and eggs
Several avian species have been domesticated for the production of food, the most important being broiler chickens and laying hens, which are currently kept all over the globe for the production of high-quality meat and eggs. Poultry meat is relatively cheap, is considered to be a healthy food, and is well accepted, as there are no restrictions on its consumption by major religions or local traditions. Poultry meat production is therefore constantly on the increase, and will soon become the most popular animal-derived food worldwide.
Ruminants: Beef cattle and dairy cows
Although meat produced via beef cattle is the least efficient of all animal protein types, it is ecologically important, as it utilizes a vegetable biomass which otherwise would be wasted to yield high-quality protein for human consumption. Ruminants can digest lignocellulosic material in their rumen; this process results in protein( bacterial biomass) and volatile fatty acids( energy) for the host animal. In most countries, the dairy industry uses cattle breeds which were genetically selected for high milk production over many generations. Dairy cows in highly developed production systems deliver on average only 2.5 lactation cycles, which is seen as a dissipation of resources, considering the long investment required to bring a calf / heifer to sexual maturity. Frequent health issues in dairy cattle, which result in the culling of cows, are fertility problems, lameness due to serious claw disorders, and chronic mastitis
Pork production
Today ' s swine industry is still less concentrated and less integrated than the poultry industry, and the production of growing and fattening pigs is less efficient than that of broilers. Pig meat is not accepted by certain religious communities such as Muslims, and accordingly this industry is not present in several large countries of the Middle East and Asia. Nevertheless, pork is the most widely consumed meat in the world.
Aquaculture
Since levels of wild shing are stagnating, aquaculture has developed exponentially in order to satisfy the growing demand for this type of food. Farming of aquatic species represents the most diverse food-producing industry, ranging from invertebrates such as mollusks and crustaceans and a large variety of sh to reptiles such as crocodiles. �e animals belong either to freshwater or marine species, and rearing takes place in tanks, ponds, rivers, lakes and the ocean. A special requirement of carnivorous sh species such as salmonids is that they need shmeal for fast growth, which is produced in enormous quantities via the processing of wildcaught sh. As such farming conditions might not be sustainable in the future, research efforts are directed towards diet compositions which allow using more vegetable protein, e. g. soya. Moreover, there are indications that aquaculture could use insect protein, whose amino acid composition is largely similar to that of shmeal.
Opportunities to increase meat production
Doubling animal-derived protein production in a sustainable way represents an enormous challenge for this industry. It means nding the land for placing the farms for the additional animals, but also increasing the production of raw materials for feed, particularly the main ingredients such as corn, cereals and soybean. For the transport of both feed and animals, adequate
January- February 2017
FARMERS
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