Information &

Pig Terminology

A male castrated before it reaches sexual maturity

A mature male used for breeding purposes

To give birth to piglets

The amount of feed consumed to produce a pound of meat

A pig weighing between approximately 40 and 60 pounds

Unborn pig

To feed a pig until it reaches a market weight, approximately 180-300 pounds

A young female that has not farrowed her first litter

Any pig weighing approximately 10 – 40 pounds

Newborn pig, young or juvenile pig

A mature female that has farrowed at least one litter

To separate pigs from the sow

Primary Stages of Pig Production

  • Gilts are bred when they are approximately 6 – 8 months old.
  • Sows are bred approximately 3 days after piglets are weaned.
  • The gestation period for pigs is approximately 114 days.
  • Pigs farrow litter sizes ranging from 6 – 13 piglets.
  • The average birth weight per piglet is
    approximately 2 – 4 pounds.
  • Young pigs are introduced to regular pig feed at 10 – 12 days of age.
  • Pigs are generally weaned at three to four weeks of age.
  • Weaned pigs weigh approximately 10 – 15 pounds.
  • Weaned pigs are typically moved to a nursery and raised until they reach a weight of approximately 40 – 60 pounds.
  • Pigs are moved to a finishing barn at
    approximately 8 weeks of age and approximately 40 – 60 pounds.
  • Pigs will remain at a finishing barn until they reach market weight of approximately 180 – 300 pounds.
  • When pigs reach approximately 180 – 300 pounds, producers sell them to an abattoir.
  • Market hogs are typically 5 – 6 months old.
  • It takes approximately 10 months after successful breeding for pigs to reach market weight.

Pig Production Essentials

Pig producers need approximately 18 to 20 months to alter the supply chain once a decision is made to increase or decrease production. The times referenced below are all approximate times.

Feed is the major input to the pork production process, accounting for about two-thirds of costs. The average whole-herd feed conversion ratio .

(pounds of feed required per pound of live weight produced) for the U.S. pork industry is 3.4 to 3.6 and continues to improve. For example, it takes 900 pounds of feed to raise a 250lb pig (3.6 x 250).

Pig prices vary cyclically and seasonally. Cyclical variation is caused by the time lags inherent to biological production. When prices are high, more sows are bred and more pigs are produced; however, these pigs will not reach the market until approximately 10 months after they are conceived. When they do, supplies increase and prices fall, thus causing a price cycle. Seasonal variation is caused by changes in production efficiency due to weather and different demand levels.


Most housing for pigs has slotted floors that allow the pigs’ waste to fall through into a holding pit or gutter. This keeps the floors drier and cleaner and makes it easier to provide the correct environment to keep pigs comfortable and productive, as well as minimizing disease and biohazards.

Growth Cycle

Pigs grow at a very different rate in comparison to humans. A pig grows very quickly and is considered mature at approximately 4-6 months of age.

* Numbers are approximate due to natural variations in animal growth rate.
Note: Please refer to Pig Terminology list at the top of the page.

Tissue Project Tips/FAQs

Organizing a Successful Porcine Tissue Project

Does your project require the host animal to be a specific breed, age or within a specific weight range?  Do you need traceability information regarding the gender, individual weight of the animal, or the average weight of a group of animals used for collection? If these factors are important, Tissue Source gives you the opportunity to specify these parameters with the Custom Animal option. If your project doesn’t require the tissue collected from animals with special requirements, the Basic Animal option will provide the most cost-effective option.

Tissue Source offers options for tissue traceability back to the individual animal or back to the lot of animals. Additionally, options for tissue rinse solutions, packaging solutions, shipping temperature range and logistical options are offered. If you do not have specific tissue requirements, then Basic Tissue will provide the most cost-effective option. Tissue Source’s knowledgeable staff can help analyze your collection needs and provide options to maximize your purchase value.

What quantity of tissue do you need? How often will you need the tissue? Do you require a specific number of samples to be collected over a particular time period? Tissue Source supplies one-off collection requests as well as standing orders, and everything in between. Discounts may be available for contractual recurring orders.

Prospective collections can be scheduled within ten days if the existing specifications and purchase order are already in place. However, new tissue orders may take some time as clarification of specifications, acquisition of appropriate age/weight animals, and purchase of requested packaging and shipping items may be required. Depending on the complexity of your request, it may take several weeks before your collection can be scheduled. It is always best to inquire early!

In most cases, tissues are collected and shipped the same day the animal is sacrificed, primarily using overnight commercial delivery. Special delivery options can be arranged.

The overwhelming majority of the animals that are used as a source for tissue collection are USDA inspected. The exceptions are found when the customer’s specifications require animals that are outside of the range of animals processed in a USDA-inspected abattoir facility. Examples include collection of fetal tissue or tissues from less than market size animals

  • One month of age corresponds to the same numerical date from one calendar month to another. For example, a pig that was born on March 8th turns one month of age on April 8th, 2 months of age on May 8th and so on.
  • In the same manner, a pig will remain that age in months until the next calendar month. For example, a 5-month-old pig that was born on March 8th will turn 6 months of age on September 8th. The pig is still considered 5 months of age on September 7th (i.e., 5 months and 30 days)
  • This information can be verified by entering birth dates on the Age Calculator page on