Pasture Systems
Use of forages can lower costs of grain and protein supplementation. In the
case of pasture systems, equipment and building costs decrease, resulting
in lower fixed costs of production (PIH-13). If sows are bred in the late
spring to farrow early fall, good quality forage can replace up to 50% of
grain and supplement needs. One acre of good pasture can accommodate up to
8 sows for a season. During other seasons of the year, however, forage quality
and availability will vary, and supplementation with corn and protein supplement
will need to adjust to provide the necessary nutrients.
Available
recommendations on stocking rates for grow-finish hogs on pasture vary considerably
with soil fertility, pasture species, rainfall, and season impacting forage
availability and quality. Available recommendations for pigs weighing less
than 100 pounds are 15–30 pigs per acre and 10–20 pigs per acre
for pigs weighing over 100 pounds. These numbers can be increased significantly
with more intensive management such as rotational grazing. Grow-finish pigs
on pasture are full-fed in most instances. However, some observations suggest
limit feeding can be practiced with sufficient nutrient contributions coming
from the pasture. Research focusing on the nutritional contributions of pasture
with current swine genetics and management is limited.
A sample pasture mix might consist of seedings for permanent, rotational,
or annual pastures. The permanent pasture might contain seedings of bluegrass,
white clover, orchardgrass, and alfalfa. The rotational pasture may include
alfalfa, red clover, ladino clover, sweetclover, alsike clover, orchardgrass,
bromegrass, and Timothy grass. An annual or temporary pasture could be made
up of brassicas, rape, soybeans, cowpeas, fababeans, sudangrass, rye, oats,
wheat, barley, field peas, and mixes of grass and legumes (Zeller, 1948).
Example diets that have been presented do not assume pasture supplementation
due to the wide variation in forage or pasture types used, and will therefore
need to be adjusted based on nutrients provided from the pasture.
