6.1 RUMINANT LIVESTOCK 135 What animals are raised as livestock? Energy is not actually a nutrient but the total caloric value of a feed. Energy is obtained from carbohydrates in the plant material and can be stored in the form of body lipids. ONLINE RESOURCES Rare breed survival broiler house: allevamento intensivo per polli feedlot: recinto di ingrasso del bestiame gizzard: ventriglio proventriculus: proventriglio, stomaco ghiandolare roughage: fibra shelter: riparo to soak: inzuppare 282 LIVESTOCK ANIMAL HUSBANDRY Animal husbandry is the practice of breeding livestock and is essential to modern agriculture in meeting people s nutritional needs, increasing farmers income and promoting farmers development. This activity implies providing animals with shelter and feed and taking care of their health. The term livestock does not include pets and refers only to domesticated animals, either ruminants or non-ruminants, raised for pleasure or profit; they can provide meat, milk, eggs, fibres and textiles, manure and/or labour. Modern animal husbandry relies on production adapted to the type of land available. Subsistence farming, which provides only all the products for the consumption of the farm family without any surplus for trade, is being replaced by intensive animal farming in the more developed parts of the world. There, for example, beef cattle are kept in high density feedlots, and thousands of chickens may be raised in broiler houses or batteries. Nutritional requirements The most important aspect in keeping livestock healthy and able to produce is a proper nutritious feed. The daily diet for livestock is usually referred to as a ration, and a balanced ration is the amount of feed that will supply the proper type and proportions of nutrients needed for an animal to perform a specific purpose. The six basic components of a ration are: water, protein, energy , fibre, vitamins, and minerals. These nutrients are needed to maintain body weight, growth, reproduction, lactation, and health. Every ration will be different depending on species, age, size and weight, gender, stage of reproduction, demands for production or work, and environment. Improper nutrition (underor overfeeding) can affect animal health. On the contrary, balanced nutrition can enhance immune health, welfare, productivity, and longevity. Digestive system The digestive system is in charge of breaking down the food ingested into nutrients; it is also responsible for the absorption of these nutrients into the blood. These are the animal digestive systems: Monogastric: formed by one stomach chamber, present in humans and many other animals; Avian: it has two chambers, the proventriculus, where the food is digested by gastric juices, and the gizzard, where the food is stored, soaked, and mechanically processed. It is the digestive system present in birds; Polygastric: typical of herbivores, it features four stomachs, rumen, reticulum, omasum, and abomasum. Pseudoruminant: the stomach has three chambers, omasum, abomasum, and reticulum, typical of camels and alpacas.