Water's essential role in pig performance

Tuesday, January 26, 2021

Producers should test their water sources regularly, ensure adequate water flow, and consider water treatment options to support herd performance.

by Kate Ayers

To help optimize production, pig farmers focus on the details.

Producers manage controllable factors to the best of their abilities and provide excellent care for their animals. Producers maintain comfortable stocking densities, supply their herds with expert-formulated diets and even provide enrichment materials.

While all these aspects of herd management are important to ensure animal welfare, perhaps the most critical component of livestock health is water. In Canada, we are fortunate to have water widely available, but the seeming prevalence of this resource also means we tend to take it for granted. We may overlook issues of quality and quantity, as water can flow to drinkers without a second thought.

Producers must provide pigs with feed, light, air, and water for the animals to grow, says Jesse McCoy. "If you have water refusal, you have pigs that are surviving but not thriving," he says.

"Poor water quality could mean increases in vet visits and higher mortality (rates) in herds. (These costs) come straight out of producers' pocketbooks. If you improve water quality, you get better feed conversion, better average daily gain, and less illness," he says.

McCoy is a business unit specialist for water treatment and animal safety at Neogen. The company is headquartered in Lansing, Michigan. Neogen provides services and solutions for the food processing, animal protein and agricultural industries to help protect the world's food supply, the company's website says.

"The more we look into it, the more we discover that water is a weak link for so many processes inside the farm," McCoy says.

"If you have pigs that are loose, you will have more manure to get rid of. (Farmers bear) the intrinsic costs of producing more feed for pigs with lower daily gains.

"And, if water stinks, people won't want to use the shower-in and -out facilities. So, biosecurity can fail," he says.

This month, Better Pork speaks with McCoy, a swine veterinarian, professors, and other industry experts to explore the importance of water for herd health and animal performance. We discuss water's roles in physiological processes, the importance of water flow, as well as water testing and treatment options.

Water's roles in the body

All organisms must consume water, as it is vital for survival.

Water "provides structure to the body through cell turgidity. Water plays a critical role in temperature regulation. Water also aids in the movement of nutrients to cells and in the removal of waste from the cells and body," says Dr. Laura Eastwood. She's a swine specialist for the Ontario Ministry of Agriculture, Food and Rural Affairs and is based in Stratford.

Water "plays a role in nearly every chemical reaction that occurs within the body and provides lubrication for joints (synovial fluid) and protective cushioning for the nervous system (cerebrospinal fluid)."

Indeed, "water makes up as much as 82 per cent of a neonatal pig and about 50 per cent of a market pig," she says.

Water plays a role in digestion, too.

"Pigs need between 2.5 and 2.7 times more water than the weight of feed they consume," says Dr. John Patience. "So, if the pig consumes 1 kilogram (2.2 pounds) of feed, it needs at least 2.5 kg (5.5 lbs.) of water."

Patience is a professor in the department of animal science at Iowa State University in Ames.

If pigs are "exposed to dry conditions, such as drinking-water shortages, their bodies will draw more water from their intestinal tracts," he adds. As a result, pigs with water restrictions eat less feed and have lower daily gains.

In lactating sows, water consumption is important for milk production.

"Litters that (developed) the slowest the first week after farrowing (nursed) from sows that (drank) the least amount of water," seminal late-1980s Agriculture and Agri-Food Canada studies found, Patience says.

Overall, pigs need adequate supplies of fresh drinking water to carry out basic bodily functions. Animals must meet their basic physiological needs before they can become top performers in their herds.

Know your water

What separates good water from bad? How can farmers know if their water sources promote optimal herd health?

Unfortunately, "water quality is a hard thing to nail down," says Dr. Lee Johnston.

Limited comprehensive scientific literature is available on the topic, but the industry has its fair share of anecdotal evidence or perceptions, he says.

Johnston is a professor of swine nutrition and management at the University of Minnesota in Minneapolis.

Dr. Jennifer Demare agrees. A clear definition of poor water quality is challenging, she says.

Demare is a veterinarian at Swine Health Professionals Ltd. in Steinbach, Man.

"A number of factors affect water quality, including nitrates, pH, and sulphates. What is it exactly that we are looking at?" she asks.

"Any one of those components may be flagged but that doesn't necessarily mean that the water is poor" or will cause adverse effects in pig performance.

Pigs' susceptibility and vulnerability to health problems from water "depends on the specific water quality issue," Eastwood says.

"Pigs of all ages can be impacted by different water quality issues. We tend to notice more effects in young pigs and breeding sows," however. Producers can more easily identify changes in performance in these groups compared to grower pigs, for example.

Nonetheless, farmers should ensure their water sources are tested regularly.

"The ideal testing frequency depends on the water source for the barn," says Dr. Bernardo Predicala. He's an engineering research scientist at Prairie Swine Centre Inc. in Saskatoon.

In barns connected to municipal or city water systems, "farmers don't necessarily need to do testing as the municipal water treatment facility conducts its own testing regularly.

"For barns with raw water sources such as untreated water from large rivers and lakes, testing frequency depends on changes in conditions that affect the water source," Predicala says. So, farmers should check their water "at least every season, or when there are drastic events – such as flooding, unusually heavy precipitation, or severe drought – that affect the quality of the source water," he says.

"The same is true for operations that draw water from groundwater wells. More frequent testing is necessary for water sourced from dugouts or sloughs, as these are more easily affected by weather conditions and other environmental factors."

Farmers should monitor such components as micro-organisms, nitrates, sulphates, pH and inorganic matter.

"A total coliform count or fecal coliform count in the water provides a good indicator of bacterial contamination in the water supply. Nitrates are not toxic to pigs, but nitrates can be converted to nitrites in the body, which are toxic," says Eastwood.

Nitrate levels of 300 parts per million (ppm) in the water can cause nitrite toxicity in pigs. Nitrates can serve as a good indicator of bacterial contamination of the water but may also be present due to high levels of nitrogenous fertilizers applied on the land, she says.

"Sulphates are the primary cause of water quality issues in well water in many regions across North America. Concentrations up to 2,650 ppm do not impact pig performance. But, when concentrations are above 7,000 ppm, young pigs can suffer from diarrhea and reduced performance as their guts do not tolerate sulphates well," says Eastwood.

"So, issues are usually observed in nursery pigs when they switch from milk to water because they are not adapted to the sulphate levels. Older pigs seem to be able to adapt to higher sulphate concentrations fairly well," she says.

"pH does not directly impact water quality, as most water sources in Ontario fall within the acceptable range of 6.5 to 8.5. Changing the pH outside of this range can have big impacts on chemical reactions involved in water treatment and can impact medication delivery," Eastwood adds.

In addition, farmers should be aware of "inorganic matter levels, such as calcium, magnesium and sodium salts. By measuring the total dissolved solids (TDS) content, you gain an understanding of the amount of dissolved inorganic matter, which can be a general measure of water quality," she says.

"As a rule of thumb, a measurement below 1,000 ppm TDS is safe with no risks to pigs. Between 1,000 and 2,999 ppm is satisfactory but may cause mild diarrhea in pigs not adapted to it. A range of 3,000 to 4,999 ppm is satisfactory but may cause a temporary refusal of water while the pigs adapt," Eastwood says.

"Measurements between 5,000 and 6,999 ppm are reasonable for non-breeding stock animals and above 7,000 ppm is unfit for pigs.

"Pigs are also fairly resilient to some common water quality issues such as hard water. The impact of hard water on the pig is minimal, but it can cause build up of scale in water systems, which leads to other challenges such as reductions in water availability," she says.

Importance of access

"The most likely way that water affects pig performance is an inadequate supply as a result of delivery systems that get old and plugged up," Patience says.

High TDS levels in water can result in residue buildup throughout water pipes and in equipment. To help prevent the development of this challenge, install drinker lines with a wider diameter than you think you need, McCoy recommends.

While the availability of water is critical for herd health, water-flow rates are also important.

Finishing pigs weighing about 90 kg (200 lbs.) should drink approximately 15 litres (3.3 gallons) of water per day, "but that pig will only drink for a certain amount of time in a day," McCoy says.

For example, "if (a pig drinks) 13 litres (2.9 gallons), but it has already spent the amount of time at the drinker that it wants, it is not going back. So, to increase volume, … you can either increase pipe diameter or increase water pressure. But, if you increase pressure, more water goes onto the ground, not into the pig."

Another factor that could affect water intake is barn density.

"When you double-stock a barn, you increase the number of pigs but not the number of drinkers. … Pigs at the front of the barn look fine, but the ones at the back (may drag) because … those pigs are water-starved," McCoy says.

Patience underscores the need to ensure even flow throughout the barn.

"The size of piping and (intensity of) water pressure are important to ensure that the pigs at the far end of the barn get the same amount of water as the pigs at the front," he says.

Elbows in water lines can also reduce the pressure beyond that point, which can lower water delivery. "This (situation) is a common issue in newly renovated barns," Patience adds.

Water treatment options

As water is important for herd health and performance, perhaps the first step farmers should take before constructing a barn is to determine the quality of water sources at potential building sites.

"Water quality problems are usually site-specific. The best option to avoid water quality problems in the first place is to select the barn site properly. Consider the quality of the available water supply at the site, among other things, before building the barn," says Predicala.

Eastwood agrees.

Once you "understand what water quality issues may be present" in your current barn or at a new site, "find a system that will handle that problem," she says.

"Choice of treatment also depends on capital cost, maintenance cost and on-going product costs."

Fortunately, many water treatment options are available. For example, producers can install chlorination systems if the water has coliform issues or acidification systems to manage high pH levels, says Redge Watt.

He is the operations manager for Fast Genetics in Spiritwood, Sask. Fast Genetics provides pork producers with breeding stock and innovative genetics solutions to assist them in providing healthier food and using fewer resources in an environmentally sustainable way.

For other water quality issues, including biofilms, sulphates and nitrates, farmers can use filtration systems, reverse osmosis, ion exchanges, and softeners to treat their water, Predicala says.

Water hardness is the sum of calcium and magnesium. Ion-exchange water softeners replace calcium and magnesium with sodium, Patience says.

In addition, "filtration options are available, ranging from activated carbon filters, sand filters, membrane filters, mechanical filters, biological filters, etc. The choice of which option to use depends on the nature of the water quality problem as well as technical and economic feasibility," Predicala adds.

Water treatment may be more challenging for farmers who are in continuous production, as they may face system maintenance challenges.

Since pigs are always reliant on the water system, cleaning lines, repairing broken pieces, or shutting down the system may be difficult, Eastwood says.

Producers should complete economic analyses of the best water treatment options available for their operations. Farmers can consult water specialists and industry experts to determine the best option for their operations.

Given the centrality of water to pork production, it may be worth a second look at the quality and flow of water in your operation. After all, adequate amounts of fresh and clean water will maintain pigs' feed intake and ensure optimal lifetime productivity. BP