Pen (enclosure) in the context of "Pet"

Fish farming or pisciculture involves commercial breeding of fish, most often for food, in fish tanks or artificial enclosures such as fish ponds. It is a particular type of aquaculture, which is the controlled cultivation and harvesting of aquatic animals such as fish, crustaceans, molluscs and so on, in natural or pseudo-natural environments. A facility that releases juvenile fish into the wild for recreational fishing or to supplement a species' natural numbers is generally referred to as a fish hatchery. Worldwide, the most important fish species produced in fish farming are carp, catfish, salmon and tilapia.

Global demand is increasing for dietary fish protein, which has resulted in widespread overfishing in wild fisheries, resulting in significant decrease in fish stocks and even complete depletion in some regions. Fish farming allows establishment of artificial fish colonies that are provided with sufficient feeding, protection from natural predators and competitive threats, access to veterinarian service, and easier harvesting when needed, while being separate from and thus do not usually impact the sustainable yields of wild fish populations. While fish farming is practised worldwide, China alone provides 62% of the world's farmed fish production. As of 2016, more than 50% of seafood was produced by aquaculture. In the last three decades, aquaculture has been the main driver of the increase in fisheries and aquaculture production, with an average growth of 5.3 percent per year between 2000 and 2018, rising from 32.4 to 82.1 million tonnes.

A plantation complex was a large-scale agricultural estate, common in the Americas from the 17th to the 20th century, that was structured as a self-sufficient community to produce cash crops for profit. Plantation complexes were common on agricultural plantations in the Southern United States from the 17th into the 20th century. The complex included everything from the main residence down to the pens for livestock. Until the abolition of slavery, such plantations were generally self-sufficient settlements that relied on the forced labor of enslaved people.

Plantations are an important aspect of the history of the Southern United States, particularly before the American Civil War. The mild temperate climate, plentiful rainfall, and fertile soils of the Southeastern United States allowed the flourishing of large plantations, where large numbers of enslaved Africans were held captive and forced to produce crops to create wealth for the planter class, normally a white elite.

A feedlot or feed yard is a type of animal feeding operation (AFO) which is used in intensive animal farming, notably beef cattle, but also swine, horses, sheep, turkeys, chickens or ducks, prior to slaughter. Large beef feedlots are called concentrated animal feeding operations (CAFO) in the United States and intensive livestock operations (ILOs) or confined feeding operations (CFO) in Canada. They may contain thousands of animals in an array of pens.

The basic purpose of the feedlot is to increase the amount of fat gained by each animal as quickly as possible; if animals are kept in confined quarters rather than being allowed to range freely over grassland, they will gain weight more quickly and efficiently with the added benefit of economies of scale.

Chicken wire, or poultry netting, is a mesh of wire commonly used to fence in fowl, such as chickens, in a run or coop. It is made of thin, flexible, galvanized steel wire with hexagonal gaps. Available in 1⁄2 inch (about 1.3 cm), 1 inch (about 2.5 cm) diameter, and 2 inch (about 5 cm), chicken wire is available in various gauges—usually 19 gauge (about 1 mm wire) to 22 gauge (about 0.7 mm wire). Chicken wire is occasionally used to build inexpensive pens for small animals (or to protect plants and property from animals).

Kraal (also spelled craal or kraul) is an Afrikaans and Dutch word, also used in South African English, for an enclosure for cattle or other livestock, located within a Southern African settlement or village surrounded by a fence of thorn-bush branches, a palisade, mud wall, or other fencing, roughly circular in form. It is similar to a boma in eastern or central Africa.

In Curaçao, another former Dutch colony, the enclosure was called "koraal" which means coral and which in Papiamentu is translated "kura", a word still in use today for any enclosed terrain, like a garden.

The meat industry are the people and companies engaged in modern industrialized livestock agriculture for the production, packing, preservation and marketing of meat (in contrast to dairy products, wool, etc.). In economics, the meat industry is a fusion of primary (agriculture) and secondary (industry) activity and hard to characterize strictly in terms of either one alone. The greater part of the meat industry is the meat packing industry – the segment that handles the slaughtering, processing, packaging, and distribution of animals such as poultry, cattle, pigs, sheep and other livestock.

A great portion of the ever-growing meat branch in the food industry involves intensive animal farming in which livestock are kept almost entirely indoors or in restricted outdoor settings like pens. Many aspects of the raising of animals for meat have become industrialized, even many practices more associated with smaller family farms, e.g. gourmet foods such as foie gras. This heavy industrialization leads to an outsized environmental impact, responsible for significant greenhouse gas emissions, land use change and degradation, and water, air and soil pollution.