July, 1999 . Volume 22, Number 6 
NCSU Extension Swine Husbandry
July, 1999 . Volume 22, Number 6
Waste management issues are not only affecting swine producers in North Carolina. Other swine
producing regions around the world have been, or are in the process of being subjected to
increased governmental scrutiny of production practices.
In Korea, the government has imposed very stringent regulations on the handling of manure.
Korea is a little smaller than North Carolina, but less than 1/4th of the Korean
surface area is arable land. In this relatively small area live 50 million people and about
7 million pigs, competing for resources. The result of this high concentration of people is
that arable land is perceived as very valuable; one acre sells for over $100,000!
Swine producers typically own little more land than the area covered by their barns (and
barns are put in very close proximity). Thus, production is not linked to the land required
to spread the manure as a fertilizer. Instead, farmers process the manure in order to make
a value-added product through composting.
In brief, pigs are typically housed such that urine and feces can be collected separately.
For sows, this is achieved by positioning buildings on a slope that allows the urine to
drain into a collection pit, while the feces stay behind. These feces are then collected
once or twice a day using manual labor.
Grow-finish pigs are typically housed on partially slatted floors. The slatted area, however
, is relatively small (less than 1/4th of the pen space). Under these slats is a
scraper that allows for the separate collection of feces and urine. As the slatted area is
small, manure is (manually) scraped once or twice daily from the non-slatted floor portion
onto the slatted area.
Feces are mixed with wood shavings and stacked in a composting building. These buildings
typically consist of a concrete floor and (low) retaining walls, and a translucent,
corrugated roof (comparable to a hoop structure). The fecal material is turned over
frequently, either automatically, using a bobcat, or even manually. The end-product is
relatively odorless, dry product that is sold as a fertilizer.
Urine either is mixed in with the wood shavings and the feces for composting, or is sprayed
on partially composted material. Alternatively, urine is processed in treatment facilities
that mimic sewage treatments plants. After processing, the remaining material is discharged
in surface waters. A problem with the treatment of urine is that it is difficult to meet the
discharge guidelines, and material typically has to be diluted prior to discharge.
The Korean waste treatment system is interesting in that it produces an end-product that is
attractive to local crop producers as a fertilizer. This stimulates the recycling of
nutrients. However, this system also requires a large labor input; farms with 250 sows
employ 4 to 5 persons, and a major portion of the time is spent on cleaning pens and
collecting manure.
Also, the system requires a major investment in capital, as separate buildings and equipment
is needed to process the waste. It is estimated that waste processing costs at least $8 per
pig finished (in a country where the average income is $7000 per year). In a global economy,
such a penalty puts the Korean swine industry at a disadvantage, and in part as a result of
waste management regulations, the Korean industry depends heavily on government subsidies
and import restrictions to maintain its industry.
Theo van Kempen
Summertime is here and for pork producers in the southeast that means that the hot, humid
days will soon be here. It is time to start making plans and evaluating swine facilities
for helping pigs cope with the summertime weather. As the temperature and humidity climb
you can expect to see increased death losses in the units and during trucking, reduced
growth performance, reduced boar fertility, delayed heat, reduced ovulation rate, and
increased embryonic death if animal comfort is not maintained. The Livestock Conservation
Institute has developed a weather safety index that indicates producers should be on the
alert at temperatures greater than 75 degrees, the Danger Zone is anytime temperatures are
above 100 degrees and the Emergency Zone is above 100 degrees with 25% or greater humidity.
The following points should be checked and considered: Pig handling, inspection of watering,
ventilation and cooling equipment, follow trucking guidelines and plan for seasonal
infertility.
Pig Handling
Pay extra attention to the movement of animals. Keep the pigs calm, move them
slowly and refrain from using electric prods. Consider changing the pig movement schedule
to early in the day or late in the evening when it is cooler. Heat will increase the stress
on an animal during movement.
Adequate space to reduce fighting and improve pig performance is also more critical in
warmer weather. Nursery pigs need 1.7 to 2.5 sq. ft. per pig. In the finisher pig space
needs grow as the pig grows starting at a 5 sq. ft. per pig at placement (50 lb.) and ending
with 8 sq. ft. per pig at 150 lb. to market.
Ventilation and Cooling
Inspect and maintain fans, cool cell pads, drip and spay cooling systems and air inlets.
Take special care to check for worn fan belts that may dramatically reduce the ventilation
rate. Also the nozzles in drip and spray cooling systems may have become plugged with
sediment from periods of inactivity. These nozzles should be checked and cleaned.
Watering
Water usage will increase for each type of animal in the summertime. A sow and litter will
require 8 gal/day while a nursery pig will need 1 gal/day, a finisher 5 gal/day and a sow in
gestation 6 gal/day. Nipple waters should be checked for minimum flow rates to ensure that
the animals can achieve their minimum water requirements. In the nursery the flow should be
1 to 1 1/2 cups per minute while in the finisher, farrowing, breeding and gestation barns
the flow rate should be at least 3 to 4 cups per minute. Also, check to make sure that
enough nipples are available to accommodate all of the pigs in a pen. In the nursery 10
pigs/nipple is recommended and this can be increased to 15 in the finisher.
Breeding Herd
It is important during warm weather to maintain the breeding herds feed intake. Loss of
weight, expecially during lactation contributes to seasonal anestrus. This can be
accomplished by feeding when temperatures are lowest in the early morning or evening and by
feeding smaller meals more frequently. Formulation changes can also be beneficial by adding
fat and increasing the concentration of other nutrients in the diet to ensure the pigs needs
are met when their feed intake declines.
Temperatures that are greater than 85 degrees Farenheidt may reduce semen quality for 4 to 6
weeks. When temperatures rise monitor the boars respiration rate. Normal respiration is 25
to 35 breaths per minute and heat stress is 75 to 100 breaths per minute. When the boars
respiration reaches 40 to 50 breaths per minute intervene and take measures to cool the
boars.
Seasonally infertility is also well documented. If your herd has historically had a seasonal
infertility problem take steps in order to reach your breeding target. This can be
accomplished by breeding up to 40% more females depending on the decline you see in
farrowing rate. Breeding targets should increase gradually through May, June, July and
August and decline through September to a normal level.
Remember that keeping boars fertile is just as important and keeping the sow herd
comfortable. Two weeks of exposure to 80 degree plus temperatures cause a dramatic increase
in abnormal sperm and a reduction in motility. It will take the boar a minimum of four
weeks to recover from heat stress. Boars may also become lethargic and have reduced libido
during periods of hot weather.
Trucking Tips
When trucking animals load and unload promptly and do not make stop. Animals should be wet
prior to transport on hot days. Trucks should also be used that provide maximum ventilation
and the use of wet sand or wet shavings for bedding can be beneficial. For 250 pound hogs
you should have about 1.8 head per running foot of floor that is 92 inches wide. The
Livestock Conservation Institute that in the alert zone 10% fewer hogs should be loaded and
deliveries should be made by 11:00 am. In the Danger zone 20% fewer hogs should be loaded
and deliveries made at night and when the Emergency Zone is reached trucking should be
postponed if possible until the weather moderates.
Todd See
It is once again time to make plans for the annual N.C. Performance Market Hog Show.
This annual event combines fun and fellowship at the N.C. State Fair with an excellent
educational opportunity. Pigs that are nominated, ear-tagged and weighed on-test by
July 23rd can be exhibited in the performance market hog classes at the fair, where they
will be evaluated both live and on the rail. For the live competition, the judge is
provided with the average daily gain of each animal, which he uses along with visual
appraisal, to determine a ranking. On the rail, the pork carcasses are evaluated for fat
depth, loin muscle area, carcass length, loin muscle color, loin muscle marbling, loin
firmness and carcass weight. These measures are combined to predict the pounds of lean gain
per day on-test, which is used for the final ranking. In today's competitive pork industry,
the amount and quality of carcass information collected on the pigs in this program can be
quite valuable. Anyone interested in nominating pigs for the 1999 event should contact
their County Extension Livestock Agent on or before July 16, 1999.
Todd See