Pig farming is the raising and breeding of domestic pigs. It is a branch of animal husbandry. Pigs are raised principally as food (e.g. pork, bacon, gammon) and sometimes for their skin.
Pigs (hogs in the US) can be farmed as intensive commercial units, commerial free range enterprises, small-scale farming being allowed to wander around a village, or tethered in a simple shelter. Today, pig farms are much larger than in the past, with most large-scale farms housing 5,000 or more pigs in climate-controlled buildings. With 100 million pigs slaughtered each year, these efficiencies deliver affordable meat for consumers and larger profits for producers.
Individual farm management focuses on housing facilities, feeding and ventilation systems, temperature and environmental controls and the economic viability of their operations. Just as producers have to determine profit margins and types of facilities and equipment for their farm, they must also find the practices that best fit their specific situation. Some procedures and treatments are known to stress the animals and producers should consider the animals' welfare, health and management in correspondence with accepted husbandry skills.
There are various methods of pig farming depending on the method of management adopted. Variables include:
- Money or capital available
- The type of pigs kept
- Local requirements and market conditions
- The level of management skills
Use as food
Almost all of the pig can be used as food. Preparations of pig parts into specialties include: sausage, bacon, gammon, ham, skin into pork scratchings, feet into trotters, head into a meat jelly called head cheese (brawn), and consumption of the liver, chitterlings and blood(blood pudding or black pudding).
Production and trade
|Global pig stocks
|People's Republic of China||425.6|
UN Food & Agriculture Organisation
Pigs are farmed in many countries, though the main consuming countries are in Asia, meaning there is a significant international and even intercontinental trade in live and slaughtered pigs. Despite having the world's largest herd, China is a net importer of pigs, and has been increasing its imports during its economic development. The largest exporters of pigs are the United States, European Union, and Canada. As an example, more than half of Canadian production (22.8 million pigs) in 2008 was exported, going to 143 countries. Older pigs will consume eleven to nineteen litres (three to five gallons) of water per day.
Relationship between handlers and pigs
The way in which a stockperson interacts with pigs affects animal welfare which in some circumstances can correlate with production measures. Many routine interactions can cause fear, which can result in stress and decreased production.
There are various methods of handling pigs which can be separated into those which lead to positive or negative reactions by the animals. These reactions are based on how the pigs interpret a handler’s behavior.
Many negative interactions with pigs arise from stockpeople dealing with large numbers of pigs. Because of this, many handlers can become complacent about animal welfare and fail to ensure positive interactions with pigs. Negative interactions include overly-heavy tactile interactions (slaps, punches, kicks and bites), the use of electric goads and fast movements. These can result in fear in the animals, which can develop into stress. Overly-heavy tactile interactions can cause increased basal cortisol levels (a "stress" hormone). Negative interactions that cause fear mean the escape reactions of the pigs can be extremely vigorous, thereby risking injury to both stock and handlers. Stress can result in immunosuppression, leading to an increased susceptibility to disease. Studies have shown that these negative handling techniques result in an overall reduction in growth rates of pigs.
Various interactions can be considered either positive or neutral. Neutral interactions are considered positive because, in conjunction with positive interactions, they contribute to an overall non-negative relationship between a stockperson and the stock. Pigs are often fearful of fast movements. When entering a pen, it is good practice for a stockperson to enter with slow and deliberate movements. These minimize fear and therefore reduce stress. Pigs are very curious animals. Allowing the pigs to approach and smell whilst patting or resting a hand on the pig's back are examples of positive behavior. Pigs also respond positively to verbal interaction. Minimising fear of humans allow handlers to perform husbandry practices in a safer and more efficient manner. By reducing stress, stock are more comfortable to feed when near handlers, resulting in increased productivity.
Prohand for pigs is a training program that teaches handlers to interact with pigs in a way that promotes safe handling. It promotes the development of positive behaviors and elimination of negative behaviors. This program has been seen to improve productivity without any capital investment.
Pig farming terminology
Pigs are extensively farmed, and therefore the terminology is well developed:
- Pig, hog or swine, the species as a whole, or any member of it. The singular of "swine" is the same as the plural.
- Shoat, piglet or (where the species is called "hog") pig, unweaned young pig, or any immature pig.
- Sucker, a pig between birth and weaning.
- Runt, an unusually small and weak piglet, often one in a litter.
- Boar or hog, male pig of breeding age.
- Barrow, male pig castrated before puberty.
- Stag, male pig castrated later in life (an older boar after castration).
- Gilt, young female not yet mated, or not yet farrowed, or after only one litter (depending on local usage).
- Sow, breeding female, or female after first or second litter.
Pigs for slaughter
- Suckling pig, a piglet slaughtered for its tender meat.
- Feeder pig, a weaned gilt or barrow weighing between 18 kg (40 lb) and 37 kg (82 lb) at 6 to 8 weeks of age that is sold to be finished for slaughter.
- Porker, market pig between 30 kg (66 lb) and about 54 kg (119 lb) dressed weight.
- Baconer, a market pig between 65 kg (143 lb) and 80 kg (180 lb) dressed weight. The maximum weight can vary between processors.
- Grower, a pig between weaning and sale or transfer to the breeding herd, sold for slaughter or killed for rations[clarification needed].
- Finisher, a grower pig over 70 kg (150 lb) liveweight.
- Butcher hog, a pig of approximately 100 kg (220 lb), ready for the market. In some market (Italy) the final weight of butcher pig is in the 180 kg (400 lb) range. This to have hind legs suitable to produce cured ham.
- Backfatter, cull breeding pig sold for meat; usually refers specifically to a cull sow, but is sometimes used in reference to boars.
- Herd, a group of pigs, or all the pigs on a farm or in a region.
- Sounder, a small group of pigs (or wild boar) foraging in woodland
- Trotters, the hooves of pigs (they have four hoofed toes, walking mainly on the larger central two).
- In pig, pregnant.
- Farrowing, giving birth.
- Hogging, a sow when on heat (during estrus).
- Sty, a small pig-house, usually with an outdoor run or a pig confinement.
- Pig-shed, a larger pig-house.
- Ark, a low semi circular field-shelter for pigs
- Curtain-barn, a long, open building with curtains on the long sides of the barn. This increases ventilation on hot, humid summer days.
- Shute, Nancy"Food & America: Pork: Building a Better Pig.". 18 May 1743. Retrieved 24 Feb 2011.
- Hemsworth, P.H. (2003). Human–animal interactions in livestock production. Applied Animal Behaviour Science 81(3): 185-198.
- Hemsworth, P.H., et al. (2000). Relationships between human-animal interactions and productivity of commercial dairy cows. Journal of Animal Science, 78(11): 2821-2831.
- Hemsworth, P.H., E.O. Price, and R. Borgwardt, (1996). Behavioural responses of domestic pigs and cattle to humans and novel stimuli. Applied Animal Behaviour Science 50(1) 43-56.
- Swine Study Guide from UC Davis