|
NCSU Extension Swine Husbandry
WATER SYSTEMS FOR GROWING SWINE
- Abstracted from
“Water Systems for Swine”
Water is the nutrient that swine require in largest quantity. But compared to the other nutrients supplied by feed, it is the most frequently misunderstood and mismanaged. While various sources recommend that water be available free choice, most fail to offer specific c recommendations as to number of drinking spaces, drinker type, and delivery rate of drinkers. They also fail to specify quality parameters.
In contemporary swine production facilities, decisions must be made concerning all of the above. In addition, the cost of water acquisition and the storage and disposition of wasted water have led producers to seek a better understanding of the water needs of pigs.
At birth, water accounts for 82 percent of the pig’s empty body weight. By the time the pig weighs 240 pounds, water comprises only 51 percent of the empty body weight. In addition to body tissue and metabolic functions, water is used for a) adjustment of body temperature, b) maintenance of mineral homeostasis, c) excretion of the end products of metabolism (particularly urea), d) achievement of satiety (gut fill), and e) satisfaction of behavioral needs.
Nursery and grow-finish
The number of pigs in a group (pen) apparently influences water usage, too. In one study, water usage was higher when pigs were housed in groups of 60 versus groups of 20. When group size increased, total drinking time per pig decreased, even though the number of pigs per drinker was the same for both group sizes.
Water:feed ratios for liquid feeding systems typically range from 2.5:1 to 3.5:1. Recently, water:feed ratios ranging from 1.78:1 to 2.79:1 for pigs weighing from 40 to 250 pounds and fed dry feed ad libitum have been reported. The lowest reported water:feed ratios were with wet/dry feeders and bowl drinkers, whereas gate-mounted nipple drinkers had the highest ratios. With similar performance, this suggests that the major cause of differences in water:feed ratios between the various drinking devices is due to differences in water wastage, not differences in the amount consumed.
Water:feed ratios decrease as pigs grow. For example, in two experiments, water:feed ratios with gate-mounted nipple drinkers were 3.35:1 for 40- to 55-pound pigs, declining to 2.27:1 and 2.58:1 for 209-pound pigs. When pigs were given water only in the feeding trough using a commercially available wet/dry feeder, water:feed ratios declined from 2.11:1 to 1.50:1; when pigs were offered water using a bowl drinker, the ratios declined from 2.11:1 to 1.77:1. Recent on-farm data support the conclusion that water:feed ratios decline as pigs grow, with a ratio as low as 1.5:1 common in facilities that use wet/dry feeders or stainless steel bowl drinkers in late finishing. Assuming similar water:feed ratios for both barrows and gilts, it follows that barrows drink more water than gilts since barrows eat more feed per day than gilts in mid to late finishing. Pigs fed meal diets drink more water than pigs fed pelleted diets, reflecting similar water:feed ratios and differences in feed conversion efficiency.
General recommendations exist for the number of pigs per drinking device, but research to support these recommendations is limited. Researchers using 3- to 4-week-old weaned pigs reported a slight reduction in average daily gain and an increase in weight variation within pens of 16 pigs given access to one versus two nipple drinkers for five weeks post-weaning. Generally, for groups larger than 10 pigs in a nursery and 15 to 20 pigs in a grow-finish facility, a minimum of two delivery devices are recommended.
Grow-finish pigs spent from 3 to 16 minutes per day at nipple drinkers when flow ranged from 1,100 milliliters per minute down to 100 ml/min. This suggests pigs will exert some extra effort in order to obtain water, but it is not clear at what point having to wait for drinker access or exert extra effort impairs performance.
Flow rate recommendations
Research supports the conclusion that one nipple drinker per 16 to 22 pigs is inadequate. These results are in contrast to the conclusions that providing one versus two nipple drinkers per 20 grow-finish pigs does not affect drinking behavior, social behavior, or production.
Number of drinkers
With wet/dry feeders, the general recommendation is to allow up to 12 pigs per feeder space. There are no data available to suggest an appropriate stocking density for tube feeders or bowl drinkers. Many manufacturers recommend no more than 20 to 25 pigs per bowl drinker.
Water supply
Water supply lines should be sized to have friction losses of less than one pound per square inch (psi) per 100 feet of pipe and flow velocities of less than 4 feet per second. Thus, in order to supply 10 gallons per minute, the pipe must have an inside diameter of one inch (Table 2).
Water and manure
Production systems that store manure in deep pits under fully slatted floors are selecting drinker devices that limit the amount of water wastage (and resultant manure volume) in order to increase the amount of available manure storage capacity. Water usage is in the range of 1 gallon per grow-finish pig per day with wet/dry feeders and bowl drinkers and 1.5 gallons per pig per day with gate-mounted nipple drinkers. Manure production patterns follow water usage.
While manure volume varies with water wastage, the total nutrients (N, P, and K) in the manure do not. Even though there is less total volume of manure to deal with when drinkers that minimize water wastage are used, the total amount of land needed for responsible land application of the collected nutrients does not vary, just the amount applied per acre. In addition, when water wastage is minimized, the stored manure can have dry matter concentrations as high as 8 to 10 percent. This compares to manure in deep pits having dry matter concentrations in the range of 3 to 4 percent when pigs used nipple drinkers. This difference in dry matter content means different equipment may be needed to agitate, load, and apply the liquid manure, depending on the drinking device.
In production systems where manure is stored in a lagoon and applied with irrigation devices, water savings associated with drinkers are of less concern. In fact, water wastage from drinker devices may make manure flow easier through pipes to the lagoon. The waste water also contributes to a more dilute lagoon effluent, reducing the risk of odors from the manure storage device.
Summary
References
2005 N.C. PERFORMANCE MARKET HOG SHOW
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 22 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 2005 event should contact their County Extension Livestock Agent on or before July 15, 2005. —Todd See
—Frank Hollowell, David Lee Number of accesses to this file: |
|||||||||||||||||||||
July, 2005
. Volume 28, Number 06