Project title:                                Effects of Water Quality on Nursery Pig Performance and Health

Principal Investigator:           Lee J. Johnston, Professor

Institution:                                   University of Minnesota

Collaborators:                             Brigit Lozinski, Pedro Urriola, Jerry Shurson, Melissa Wilson, Yuzhi Li, Milena Saqui-Salces, Brent Frederick

 

  1. Abstract

The primary objective of this project was to determine if differences in water quality influence growth performance and health of nursery pigs.  In the first phase of this project, we surveyed pork producers in Minnesota to determine their perceptions of water quality being fed to nursery pigs and how quality of water might influence pig performance and health.  Fifteen producers representing 48 barns responded to the survey.  These producers reported their perceptions of water quality ranged from excellent to intolerable based on the waters they were feeding to pigs in their barns.  Eleven of these producers indicated that water quality might have an impact on pig performance and health.  From these 48 barns, fifteen barns were selected for sampling of water at the wellhead and analysis of 29 water characteristics.  Nearly all water samples were within guidelines for acceptable water quality to feed livestock as established by the Canadian Council of Ministers of the Environment. However, these standards are based on research conducted over 30 years ago and we do not know if these standards are still valuable.  Therefore, three waters that contained the most extreme range (low to high) in hardness, total dissolved solids (TDS) and sulfate concentrations were selected and delivered to the West Central Research and Outreach Center to be evaluated in an experiment using nursery pigs under standardized conditions.

 

Newly-weaned pigs (n = 450; age = 20 d) were used in a 40-d experiment to determine the effects of water quality on pig performance and health.  Pigs were sourced from a single commercial sow farm that was negative for both Porcine Reproductive and Respiratory Syndrome virus and Mycoplasma hyopneumoniae.  Pigs were allotted randomly to 45 pens (10 pigs/pen) and pens were assigned to 1 of 3 water treatments. There were 15 pen replicates/treatment.  Treatments were: 1) water perceived as poor quality (water A; 1,410 mg EQ CaCO3/L; 5.3 ppm Fe; 171 ppm Mg; 1,120 ppm sulfate; 1,500 ppm TDS); 2) water perceived as poor quality (water B; 909 mg EQ CaCO3/L; 5.2 ppm Fe; 91 ppm Mg; 617 ppm sulfate; 1,050 ppm TDS); and 3) water perceived as good quality (water C; 235 mg EQ CaCO3/L; 1.3 ppm Fe; 21 ppm Mg; 2 ppm sulfate; 348 ppm TDS).  Pigs received ad libitum access to waters for the duration of the study which began at the time of weaning and ended 40 days later (60 days of age). Individual pig weights were recorded weekly along with feed intake on a pen basis. Occurrences of morbidity and mortality were recorded daily. Subjective fecal scores were assigned on a pen basis and blood samples were used to determine blood chemistry, cytokine concentrations, phagocytic activity of white blood cells, and intestinal integrity. Fecal grab samples were used to establish the apparent total tract digestibility of nutrients in the diet and video cameras were used to record behavior to assess if pigs had any aversions to the quality of water provided. The statistical model considered fixed effects of water treatment, room, and their interaction with random effects of pen.  Water quality had no influence on growth performance of pigs over the entire experiment as indicated by ADG (0.46 kg; 0.46 kg; 0.47 kg) or ADFI (0.68 kg; 0.69 kg; 0.71 kg) or G:F (0.71; 0.71; 0.72) for waters A, B, and C, respectively. Except for apparent total tract digestibility of ash that was greater for pigs fed water C, water quality did not influence dry matter, protein, fiber or fat digestibility of diets.  With regard to pig health, there were no differences in blood chemistry, cytokine concentrations in blood, or gut permeability attributable to water quality treatments.  Further, phagocytic activity of monocytes and granulocytes was not affected by quality of water consumed by pigs. These results suggest that gut health and immune status among pigs fed waters A, B, and C were not different.  This observation is consistent with the lack of water quality effects on morbidity (9, 5, and 8 pigs per treatment) and deaths (0, 1, and 1 pigs per treatment) for waters A, B, and C, respectively.  Pigs did not express any aversion to the waters provided, as total time spent at the drinker did not differ among treatments. Overall, these data indicate the water qualities studied in this experiment did not impact growth performance or health of nursery pigs.  We conclude that varying water quality within current guidelines has no effect on performance and health of nursery pigs.

 

  • Introduction: In the swine industry, water is known as one of the most essential components required to achieve optimal pig performance and health, along with feed and air. Unlike feed and air, water has received little attention of researchers throughout the years. Historically, water has been low in cost, widely available, and of abundant supply in most geographic areas causing it to be known as the “forgotten nutrient.” Furthermore, little is known about the impact of water quality on pig growth performance and health. Water is complex and composed of numerous chemical and biological characteristics (Patience, 2013). However, definitions for “water quality” vary throughout literature leading to an unclear understanding of what is considered “good” and “bad” for the pig. Suggestions for livestock water quality were adopted from human standards and published by the Canadian Council of Ministers of the Environment (CCME) in 1987 and have not been revisited since (CCME, 2008). Furthermore, there is a lack of published research that discusses water quality and identifies how it affects growth performance and health of specific classes of pigs. Consequently, resources to help pork producers understand water quality are severely limited.  As a result, water quality has received minimal attention by producers.

 

Recently, pork producers have observed suboptimal performance of nursery pigs and suspect that this compromised performance could be related to poor water quality. Increased incidence of “fall-behind” pigs, an increase in the presence and severity of diarrhea, and pigs that seem to transition poorly to the nursery following weaning are all examples of producer concerns. Therefore, producers have become increasingly interested in understanding how water quality may be impacting growth performance and health of nursery pigs.

 

  1. Objectives: This project focuses on a question being asked by pork producers routinely, “Does quality of drinking water influence health and performance of newly-weaned nursery pigs?”  We hypothesized that quality of water will influence nursery pig performance and that poor quality water will negatively influence pig performance and health.

 

  1. Procedures: This project was split into three phases.  In Phase 1 of the project, a 10-question survey was distributed to pork producers in Minnesota in late May 2019.  Questions on the survey consisted of the number of pigs owned by the producer, geographic location, and many questions about their perception of water quality on their farm and the importance of water quality to nursery pig performance and health.  Respondents were asked if they would be willing to collaborate with the University of Minnesota research team in future research on water quality.  Producers were able to access and submit the survey via online platforms (GoogleForms, email, Microsoft Excel, PDF), by personal communication and/or U.S. mail.

 

In Phase 2, fifteen barns were selected from survey responses to have water sampled and analyzed in July 2019. Water sampling was completed at each barn abiding by biosecurity rules at each barn.  A collection protocol was designed to fulfill lab requirements and ensure proper water sampling.  Water was collected as close to the wellhead as possible before water was exposed to any type of water treatments.  Three samples of water were collected for the analysis of 29 analytes in three different categories; coliforms, anions, and heavy metals.  Samples were analyzed at Midwest Labs in Omaha, Nebraska.  To compare each of the 15 barns, water quality reports were assembled in a spreadsheet and compared with livestock water quality recommendations described by CCME (2008).  Three of the 15 sampled waters were selected for use in a pig performance experiment conducted in Phase 3.  One water was chosen to represent “good” water and two waters were chosen to represent “poor” water.  Selections were based on comparison with CCME recommendations.

 

In Phase 3, a pig experiment was conducted at the West Central Research and Outreach Center (WCROC) in Morris, MN using two identical nursery rooms.  Each of the three waters selected in Phase 2 were transported to the WCROC and stored in 2,500-gallon water bladders (Potable Pillow Bladder Tank, Aire Industrial; Meridian, ID; Figure 1).  Water bladders were located outside the nursery barn under a 90% shade cloth.  A new plumbing system was installed to allow delivery of any of the three waters to every pair of nursery pens.  Water flow rate from the drinker in each pen was recorded weekly.  Water samples collected from the same three drinkers per treatment were pooled weekly for analysis of E.coli, total coliforms, and aerobic plate count.  Water quality was analyzed from each storage tank upon delivery, when water from the first delivery was nearly gone, and on the final day of the experiment. Ambient temperature around the tanks was recorded every 10 minutes throughout the experiment using HOBO temperature sensors placed near each water tank.

Figure 1.  Photo of full (foreground) and empty water bladders

Photo credit:  Brigit Lozinski

Pigs were assigned randomly to pens (10 pigs/pen) in the nursery upon arrival.  Nursery pens were assigned randomly to one of three treatments that included the three waters (Waters A, B, and C) selected in Phase 2 of the project.  There were 450 pigs on test, with 150 pigs per treatment.  Pigs were allowed 0.3 m2 of floor space each.  Upon arrival, pigs were about 20 days of age from a single, high health (negative for Porcine Respiratory and Reproductive Syndrome Virus and Mycoplasma hyopneumoniae) commercial sow farm and weighed about 6.25 kg.  Across all three treatments, pigs were allowed ad libitum access to their assigned water and the same industry-relevant, four-phase feeding program (Table 1).  The phase one diet (days 1 – 4; not shown in Table 1) was a proprietary pelleted diet provided by VitaPlus Corp. (Madison, WI) containing 21% crude protein, 5.4% crude fat, 0.70% calcium, 0.67% phosphorus, and 1.4% total lysine.  This diet also included a combination of Denagard® (Tiamulin; 35 g/ton) and CTC (chlortetracycline; 400 g/ton).

 

 

Table 1. Ingredient and nutrient composition of nursery diets (as-fed basis)
Ingredient, %      Phase 2a      Phase 3b        Phase 4c
Corn 47.25 54.00 64.84
Soybean meal 12.50 25.00 30.50
Titanium dioxide pre-blendd 4.00 – –
Soybean oil 1.25 1.00 1.00
Aureomycin 50®e 0.10
Dicalcium phosphate, 21% Phosphorus 0.51 0.69 0.91
Calcium carbonate 0.47 0.49 0.90
Salt 0.46 0.40 0.58
L-Lysine 98.5% 0.39 0.47 0.48
Zinc oxide 72% 0.32 0.32 –
Vitamin trace mineral premix 0.25 0.27 0.17
Specialty proteinsf 30.37 16.09 –
Otherg 2.24 1.28 0.64
Calculated nutrient composition:
ME, kcal/lb 1,529.61 1,527.36 1,526.21
Crude protein, % 21.96 21.69 21.29
Crude fat, % 4.26 4.05 3.92
Calcium, % 0.68 0.71 0.63
Phosphorus, % 0.66 0.63 0.55
Standardized ileal digestible amino acids, %
  Lys, % 1.42 1.39 1.27
 Trp, % 0.26 0.26 0.23
  Met + Cys, % 0.80 0.81 0.72
  Thr, % 0.91 0.86 0.77  df
a All ingredients minus corn, soybean meal, soy oil, and pre-blend are provided by Nursery Base 700 (Team Nutrition, Inc., Cyrus, MN).  Fed on days 5 – 14 of the experiment.
b All ingredients minus corn, soybean meal, and soy oil provided by TNI 400 Nursery Base (Team Nutrition, Inc., Cyrus, MN).  Fed on days 15 – 28 of the experiment.
c All ingredients minus corn, soybean meal, and soy oil provided by TNI 25-80 NG Premix (Team Nutrition, Inc., Cyrus, MN).  Fed on days 29 – 40 of the experiment.
d Composed of 46.5% Soybean Meal (87.5%) and Titanium Dioxide (12.5%)
e Aureomycin 50® (Zoetis, Parsippany-Troy Hills, NJ) added to Phase 2 diet to control Streptococcus suis.
f Specialty proteins (mix of specialty animal and plant proteins)
g Other (mixture of carbohydrate sources, synthetic amino acids, flavors, preservatives, and yeast products).

 

Growth performance was measured weekly by weighing individual pigs and feed intake on a pen basis.  To assess pig health, we combined a set of clinical observations with diagnostic evaluations.  Subjective fecal scores were assigned to each pen for the first week of the experiment.  Feces were collected during the first week of the experiment to determine dry matter concentration.  Diet digestibility was determined on days 10 to 12 using titanium dioxide as an indigestible marker in the phase two diet.  Fecal samples were collected from each pen (15 pens/treatment).  Blood samples collected on day 8 of the experiment from one randomly selected pig per pen (n = 15 pigs/treatment) were used to determine blood chemistry and cytokine profiles.  A Phagotest (ORPEGEN Pharma, Heidelberg, Germany) was utilized to determine phagocytic activity of white blood cells on day 8 of the experiment by collecting blood samples from 8 pigs per treatment.  On day 12, intestinal permeability was measured by performing a differential sugar absorption test (n = 8 pigs/treatment).  Finally, pig behavior was observed for the first three days of the experiment to determine if pigs had any aversion to the water quality they were supplied.  Video cameras were used to record behavior for six daytime hours on each day and were transcribed and analyzed for the number of visits to the drinker, amount of time spent at the drinker per visit, and amount of time spent at the drinker per pig.  Data were analyzed using the Proc GLIMMIX function of SAS 9.4 using a repeated analysis for water management, growth performance, health, and behavior with fixed effects of treatment, room, and their interaction. A Chi-square analysis was used in SAS 9.4 to analyze fecal scores.  Statistical significance was set at a P-value of < 0.05 with P < 0.10 indicating a trend.

  1. Results: In Phase 1 of the project, fifteen pork producers responded to our survey representing 48 nursery barns in central, southwest, and south-central Minnesota.  Five producers owned or operated < 1,000 pigs, 5 producers owned or operated 1,000 to 5,000 pigs, and 5 producers raised > 10,000 pigs annually.  Over 75% of barns represented in the survey were supplied with water from wells, followed by a small number of producers that used municipal water and one producer who used a dugout in northern MN.  Perceptions of water quality varied among producers.  Producers indicated that 9 barns were perceived to have excellent water quality, 16 average quality water, 13 marginal, and 4 intolerable. Eleven of the 15 pork producers indicated that water quality might have an impact on pig performance and health.  Producers indicated that 21 barns had no water treatment systems in place, water or waterlines were routinely treated in 26 barns, and 2 barns were equipped with a continuous water treatment system.  Over half (n= 28) of the barns had recent water quality reports from the previous year, and 20 barns had no record of water quality analysis.  Several producers indicated they would be willing to collaborate with our research team on future water quality projects.

In Phase 2, we selected 15 barns to collect water samples for analysis.  Barns were located in pig-dense regions of Minnesota (Appendix Fig. A1).  Water samples contained a wide range of analyte concentrations (Appendix Table A1) but, for the most part, analyte concentrations did not exceed guidelines recommended by CCME (2008) for many of the common analytes (nitrates, nitrites, sulfates, total dissolved solids (TDS), bacterial contamination) measured to assess water quality.  For many analytes, CCME (2008) offers no recommendation or sets a standard of “none”.  For these analytes, most of the water samples exceeded CCME (2008) recommendations.  Based on deviation from the CCME (2008) recommendations and with input from water treatment industry experts, our research team selected waters from barns 12 (water A) and 6 (water B) to represent “poor” quality water.  Water from barn 14 was selected to represent “good” quality water.  In all three instances, waters were supplied by wells at the farm.  Initial profile of waters used in this experiment is presented in Table 2.  Characteristics of these waters did not change throughout the 40-day experiment as indicated by analyses of water samples collected from the storage bladders when the first shipment of water was nearly consumed and then again at the end of the experiment (data not shown).  Differences among the three waters in hardness and concentrations of sulfate and TDS were most notable and suggest that we successfully selected waters with vastly differing characteristics.  Concentrations of fecal coliforms, nitrates, and nitrites were very low for all three waters indicating that there was no contamination of groundwater with manures or nitrogen fertilizers.

 

 

Table 2.  Initial profile of water fed to nursery pigs
Analyte Water A Water B Water C
Arsenic, ppm < 0.10 < 0.10 < 0.10
Bicarbonate (as CaCO3), ppm 397 375 270
Boron, ppm 0.25 0.24 0.13
Cadmium, ppm < 0.002 < 0.002 < 0.002
Calcium, ppm 284 214 58.7
Carbonate (as CaCO3), ppm < 1.0 < 1.0 < 1.0
Chloride, ppm 2 0 2
Chromium, ppm < 0.01 < 0.01 < 0.01
Conductivity, mmhos/cm 2.31 1.62 0.536
Copper, ppm n.d. 0.02 0.02
Fecal coliforms, cfu/100mL < 2 < 2 < 2
Fluoride, ppm 0.2 0.2 0.4
Hardness, mg EQ CaCO3/L 1410 909 235
Iron, ppm 5.43 5.22 1.33
Lead, ppm < 0.05 < 0.05 < 0.05
Magnesium, ppm 171 90.9 21.4
Manganese, ppm 0.048 0.117 0.045
Mercury, ppm < 0.0004 < 0.0004 < 0.0004
Nickel, ppm < 0.01 < 0.01 < 0.01
Nitrate, ppm n.d.a n.d.a n.d.a
Nitrite (NO2), ppm < 0.02 < 0.02 < 0.02
pH 8 8 7.5
Phosphorus, ppm 0.12 0.15 0.1
Potassium, ppm 5.34 6.33 2.67
SARb 0.7 0.5 0.8
Sodium, ppm 64 37.4 29.4
Sulfate, ppm 1120 617 2
TDS, ppmc 1500 1050 348
Zinc, ppm 0.03 < 0.01 0.05
a n.d., Not detected.
b SAR; Sodium absorption ratio.
c TDS; Total dissolved solids.

 

The water delivery system employed in the pig experiment conducted in Phase 3 of this project functioned properly.  Average ambient temperatures recorded by temperature sensors located next to each storage bladder ranged from 21 °C (70 °F) to 5 °C (41 °F) over the course of the experiment.  These temperatures were not different across the three storage bladders (data not shown).  Water flow rates at the drinker remained fairly consistent throughout the experiment (Appendix Table A2).  During week 2 of the experiment, water flow rates varied slightly but adjustment of settings on the pressure tank for Water B corrected the problem such that pigs experienced very similar water flow rates across treatments throughout the experiment.  Weekly bacterial counts were rather variable but did not differ consistently across water treatments (Appendix Table A3).  These results provide no indication of deteriorating water quality due to bacterial growth in the storage bladders over the course of our experiment.  The high total coliform measurements likely resulted from fecal contamination of drinking cups that contaminated the water samples we collected.

The range of characteristics in waters fed to pigs had no influence on growth performance over the 40-day experiment (Figure 2).  Water fed to nursery pigs had no effect on daily weight gain, daily feed intake or gain efficiency over the entire experiment.  This observation was consistent throughout the experiment.  There appeared to be no effect of water fed to pigs on daily weight gain, feed intake or gain efficiency at any time during the experiment (Appendix Figures A2, A3, and A4).  Similar to growth performance, the water fed to pigs did not have any significant effects on digestibility of dry matter, crude protein, fiber, fat, or gross energy of diets fed during days 10 to 12 of the experiment (Table 3).  Notably, digestibility of dietary ash was significantly greater for pigs fed water C compared with waters A and B.  Water C had the lowest concentration of minerals compared with the other waters as evidenced by the low levels of hardness and TDS.  This difference in mineral content of the water may have enhanced pigs’ ability to extract minerals from their diet.

Figure 2.  Overall growth performance of nursery pigs fed different waters

Table 3. Effects of water quality on digestibility of diets fed to nursery pigs (Days 10, 11, and 12 of the experiment)
Treatment
Item, % Water A Water B Water C SE P
No. of observations 15 15 15 – –
DM 79.05 78.00 78.30 0.41 0.195
Crude protein 71.72 69.84 70.05 1.07 0.170
Fiber 26.04 16.34 16.17 3.34 0.995
Ash 56.57a 56.55a 59.02b 0.66 0.016
Fat 5.62 2.40 6.60 4.69 0.804
GE 76.45 75.12 75.24 0.50 0.125
ab Means within a row with different superscripts differ (P < 0.05).

 

We relied on a variety of measures to assess the health of pigs assigned to this experiment.  The water pigs consumed had no effect on the number of pigs that required injectable antibiotic treatments, the number of injections administered, or the overall mortality of pigs (Table 4).  The very low morbidity (4.9%) and mortality (0.4%) rates observed in this experiment suggest pigs had a very high health status throughout the experiment.  Recall that pigs were sourced from a high-health, commercial sow farm.  Similarly, subjective fecal scores (1 = firm feces to 4 = liquid feces) during the first week of the experiment were not influenced by the water pigs consumed (Figure 3).  Missing scores for days 1 and 2 indicate that pigs were not consuming enough feed to generate feces.  The low scores throughout the first week demonstrate that pigs did not experience diarrhea.  Fecal scores are a subjective measurement of diarrhea incidence but we also objectively measured incidence of diarrhea by determining dry matter content of feces.  Similar to fecal scores, water consumed by pigs had no effect on dry matter concentration of fecal grab samples collected from randomly-selected pigs within each pen on days 4 through 7 of the experiment (Appendix Table A4).  The differential sugar absorption test used in this experiment provided an assessment of gut integrity to determine if the desired gut barrier functions were influenced by the quality of water fed to pigs.  We observed no significant differences in the ratios of xylose to rhamnose, rhamnose to 3-O-methyl-glucose or xylose to 3-O-methyl-glucose in blood collected from pigs fed the three different waters (Appendix Table A5).  This result suggests that intestinal barrier function was not influenced by water treatments.

 

Table 4.  Effect of water quality on morbidity and mortality of nursery pigs
Treatment
Item Water A Water B Water C P
Total pigs, no. 150 150 150 –
Pigs treated, no. 9 5 8 0.472
Injections administered, no.a 20 19 18 0.606
Mortality, no. 0 1 1 –
aInjections of antibiotics for pigs that exhibited compromised health.

 

Figure 3.  Effect of water quality on average fecal score of nursery pigs over time (Days 3 to 7 of the experiment)

To further assess health of pigs, we characterized various aspects of the pigs’ immune system.  We measured cytokine concentrations in blood of pigs on day 8 of the experiment and found that water fed to pigs had no effect on concentration of 13 cytokines (Appendix Table A6).  In addition, we investigated if the capacity of the immune cells of pigs fed the different water was compromised using a Phagotest.  The percentage of monocytes and granulocytes that displayed phagocytosis was not different among pigs fed the three different waters in this experiment (Appendix Table A7).  This result in combination with the cytokine analysis suggests that the immune system of pigs was not affected by the water they consumed.  Finally, twenty-two traits of blood from one randomly-selected pig per pen were evaluated on day 8 of the experiment.  With the exception of bilirubin, water consumed by pigs had no influence on blood chemistry (Appendix Table A8).  All traits were within reference ranges provided by Marshfield Labs where the analyses were conducted.  Bilirubin concentrations in blood from pigs consuming water A were higher (P < 0.05) than those of pigs consuming water C but all levels fell within the reference range.

Finally, we theorized that newly-weaned pigs may have an aversion to poor quality water as they adjust to conditions in the nursery.  Video recordings of pigs in 5 pens per treatment were captured for 7 hours daily (0900 to 1600 h) over the first 3 days after pigs arrived in the nursery.  The average time pigs spent at the drinker ranged from about 27 to 40 seconds per pig per hour and was not affected by water the pigs consumed (Figure 4).  Similarly, average number of visits to the drinker per hour (Appendix Figure A5) and total time spent at the drinker per visit per hour (Appendix Figure A6) were not influenced by quality of water provided in this experiment.  We were not able to measure directly water intake of pigs in this experiment.  But, time pigs spent at the drinker provides an estimate of pigs’ willingness to seek out water.  Because there were no differences across water treatments in the number of times pigs visited the drinker or the time they spent at the drinker, we conclude that pigs had no aversions to or preferences for any particular water offered in this experiment.

Figure 4. Effect of water quality on the average time spent at the drinker per pig per hour over time (Days 1 to 3 post-weaning)

  • Discussion: The initial phase of this project indicates that pork producers in Minnesota believe that quality of water is important in pig production and can potentially influence performance and health of nursery pigs.  Producers had recently sampled and analyzed water characteristics in the past 12 months for slightly over half of the nursery barns represented in this survey.  This active monitoring of water quality supports the producers’ statements that they believe water quality is important for pig performance and health.  Of the 48 nursery barns represented in the initial survey, we selected 15 barns for further sampling and analysis of water.  These barns were located in pig-dense regions of Minnesota.  While we would have liked to sample water from more than 15 barns, we believe our sampling protocol provided a reasonable estimate of the quality of water being fed to nursery pigs in Minnesota.  The cost of collecting and analyzing water samples limited the number of barns we could realistically sample.  We are not aware of any other such survey of water quality for pigs in Minnesota.  From these 15 water samples, we selected two water samples to represent “bad” water and one sample to represent “good” water.  The common traits considered to evaluate quality of water for livestock are TDS, sulfates, and hardness among other traits.  When compared with the 15 water samples analyzed, the “bad” water samples had the two highest concentrations of hardness, and the highest and third highest concentrations of TDS and sulfates.  In contrast, the “good” water had the lowest concentrations of hardness, TDS, and sulfates.  So, we are confident that we selected waters with the greatest differences in quality to evaluate in the pig feeding experiment.  However, it is important to note that none of the waters exceeded recommended levels of hardness and TDS.  Only one water exceeded the recommended levels of sulfates by 12% while the other two waters contained sulfates well below recommended levels.

The water storage and delivery system used in the pig experiment functioned admirably.  We did not observe any changes in water quality as the experiment progressed indicating that the storage and delivery system prevented any degradation of water quality over time.  The system consistently delivered water to pigs at a constant flow rate which ensured that water availability did not confound observations of pig performance or health.

The differing qualities of water fed in this experiment did not influence performance or health of nursery pigs.  We assessed growth performance, morbidity, mortality, incidence of scours, immune system characteristics, gut integrity, diet digestibility, blood chemistry, and behavior of pigs with no indication that quality of water exerted any practically significant effects on nursery pigs.  Interestingly, water with the lowest mineral content (water C) resulted in the highest ash digestibility compared to waters with higher mineral content.  This observation merits further investigation.  Because water quality did not influence pigs and the waters fed in this experiment satisfied analyte concentrations (except for sulfates in one water) recommended by CCME (2008), we conclude that current water quality recommendations for pigs established years ago appear to be valid for modern pork production.  Older studies suggest that TDS concentration of water needs to reach over 4,000 ppm to negatively affect nursery pig performance (McLeese et al., 1992) and sulfate concentrations up to 1,600 ppm did not negatively affect growth performance of nursery pigs (Patience et al., 2004).  Therefore, all three waters fed in the current study can be considered good quality because they did not negatively influence pig performance and health.

Results of this experiment must be considered in light of the water sampling protocol employed.  Waters used for this experiment were collected from very near the wellhead at each barn which prevented any degradation of water quality caused by the water distribution system in a barn.  On commercial farms, differences in water quality caused by residues and biofilms in water distribution lines might influence pig performance.  We know that microbial contamination occurs within water distribution lines of pig barns (Leblanc-Maridor et al. 2017) but it is not entirely clear how these microbial communities might influence pig performance and health. Finally, the diets fed to pigs in this experiment reflect the use of antibiotics and feed additives similar to current practices in the industry, but there is a clear trend and necessity to decrease use of antibiotics.  It is possible that water quality similar to that used in this experiment might influence pig performance and health if antibiotics and other specialty feed additives are not used in diets.  This concept needs to be tested.

 

Conclusions:

  1. Pork producers in Minnesota are concerned about how water quality might influence performance and health of nursery pigs.
  2. Water quality did not affect performance and health of nursery pigs when water characteristics were within currently recommended guidelines. Our results suggest that current water quality recommendations support acceptable growth and health of nursery pigs.

 

  • Literature Cited:

 

Canadian Council of Ministers of the Environment (CCME). 2008. Summary – Guidelines for livestock drinking water quality. In: Canadian. Environ. Qual. Guide. Table 4.10.

Leblanc-Maridor, M. S. Brilland, C. Belloc, and P. Gambade.  2017.  Efficient waterline cleaning protocol in post-weaning rooms:  A new way to reduce antibiotic consumption?  12th International Symposium on the Epidemiology and Control of Biological, Chemical and Physical Hazards in Pigs and Pork.  Foz do Iguacu, Brazil.  Aug. 21-24, 2017.

McLeese, J. M., M. L. Tremblay, J. F. Patience, and G. I. Christison.  1992.  Water intake patterns in the weanling pig: effect of water quality, antibiotics and probiotics.  J. Anim. Prod. 54:135–142. doi: 10.1017/s0003356100020651

Patience, J.  2013.  Water in Swine Nutrition. In: L. I. Chiba, editor, Sustainable Swine Nutrition. Wiley-Blackwell, Ames, IA. 3-22.

Patience, J., A. Beaulieu, and D. Gillis.  2004.  The impact of ground water high in sulfates on the growth performance, nutrient utilization, and tissue mineral levels of pigs housed under commercial conditions.  J. Swine Health Prod. 12:228-236.

  1. Appendix:

Figure A1.  Approximate locations of 15 barns used for water quality analysis

Table A1. Received water quality analysis from Midwest Labs (Omaha, NE) of barns 1 – 8 selected from survey responses.
Barn*
Analyte Recommended Levela 1 2 3 4 5 6 7 8
Arsenic, ppm 0.5 < 0.10 < 0.10 < 1.0 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10
Bicarbonate (as CaCO3), ppm – 376 42 322 274 365 375 421 416
Boron, ppm 5 0.3 0.18 0.28 0.06 0.23 0.24 0.35 0.37
Cadmium, mg/L 0.02 < 0.002 < 0.002 < 0.002 < 0.002 < 0.002 < 0.002 < 0.002 < 0.002
Calcium, ppm 1000 180 93 167 91 84 214 164 165
Carbonate (as CaCO3) – < 1.0 1.3 < 1.0 < 1.0 1.6 < 1.0 1.1 < 1.0
Chloride, ppm None 4 6 11 12 3 0 1 1
Chromium, mg/L 1 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01
Conductivity, mmhos/cmc 0.55 – 0.75 1.36 0.82 1.16 0.70 0.90 1.62 1.29 1.32
Copper, ppm 0.5 – 5.0 0.02 n.d.b 0.02 n.d.b n.d.b 0.02 n.d.b 0.01
Fecal Coliforms, cfu/100mLd None < 2 < 2 < 2 < 2 n.d.b < 2 < 2 < 2
Fluoride, mg/L 1 – 2 0.2 0.5 0.2 0.2 0.3 0.2 0.2 0.2
Hardness, mg Eq CaCO3/L None 707 391 616 367 390 909 646 656
Iron, ppm None 3.23 0 0.34 0 0.93 5.22 3.47 3.68
Lead, mg/L 0.1 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05
Magnesium, ppm None 63 39 48 34 44 91 58 59
Manganese, ppm None 0.178 < 0.005 0.899 < 0.005 0.028 0.117 0.094 0.1
Mercury, mg/L 0.003 < 0.0004 < 0.0004 < 0.0004 < 0.0004 < 0.0004 < 0.0004 < 0.0004 < 0.0004
Nickel, mg/L 1 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01
Nitrate, ppm 23 n.d.b 0.5 2.3 5.6 n.d.b n.d.b n.d.b n.d.b
Nitrite, mg/L 10 < 0.02 < 0.02 < 0.02 < 0.02 < 0.02 < 0.02 < 0.02 < 0.02
pH 7.4 – 8.8 7.24 8.52 7.13 7.34 7.68 7.38 7.46 7.29
Phosphorus, ppm – < 0.05 1.14 < 0.05 < 0.05 0.22 0.15 0.16 0.17
Potassium, ppm None 7.39 4.79 7.48 2.81 3.67 6.33 8.32 8.91
SARe – 0.5 0.5 0.4 0.3 1 0.5 0.7 0.8
Sodium, ppm None 33.3 24.5 25.7 11.6 45 37.4 42.8 46.1
Sulfate, ppm 1000 419 413 320 67 138 617 344 344
TDS, ppmf 3000 884 535 754 458 586 1,050 838 858
Zinc, ppm 50 0.04 0.02 0.02 < 0.01 0.01 < 0.01 < 0.01 0.02
a (CCME, 2008)
b  n.d., Not detected
c Conductivity- ability of water to pass an electrical current, increases with salinity
d Fecal coliforms – bacteria caused by presence of sewage contamination.
e Sodium absorption ratio – ratio of sodium to calcium and magnesium
f Total dissolved solids
* All values with a border exceed the recommended concentration level

 

Table A1 (cont). Received water quality analysis from Midwest Labs (Omaha, NE) of 9 – 15 barns selected from survey responses.
Barn*
Analyte Recommended Levela 9 10 11 12 13 14 15
Arsenic, ppm 0.5 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10
Bicarbonate (as CaCO3), ppm – 391 386 425 397 462 270 279
Boron, ppm 5 0.18 0.21 0.12 0.25 0.22 0.13 1.16
Cadmium, mg/L 0.02 < 0.002 < 0.002 < 0.002 < 0.002 < 0.002 < 0.002 < 0.002
Calcium, ppm 1000 100 161 96.4 284 100 59 146
Carbonate (as CaCO3) – < 1.0 < 1.0 1.3 < 1.0 < 1.0 < 1.0 < 1.0
Chloride, ppm None 0 2 0 2 2 2 11
Chromium, mg/L 1 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01
Conductivity, mmhos/cmc 0.55 – 0.75 0.75 1.15 0.87 2.31 0.93 0.54 2.04
Copper, ppm 0.5 – 5.0 n.d.b n.d.b n.d.b n.d.b 0.07 0.02 0.01
Fecal Coliforms, cfu/100mLd None < 2 < 2 < 2 < 2 < 2 < 2 < 2
Fluoride, mg/L 1 – 2 0.2 0.2 0.2 0.2 0.3 0.4 0.3
Hardness, mg Eq CaCO3/L None 387 638 451 1,410 457 235 529
Iron, ppm None 1.48 2.52 1.38 5.43 1.83 1.33 0.52
Lead, mg/L 0.1 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05 < 0.05
Magnesium, ppm None 33 57 51 171 50 21 40
Manganese, ppm None 0.125 0.115 0.041 0.048 0.027 0.045 0.317
Mercury, mg/L 0.003 < 0.0004 < 0.0004 < 0.0004 < 0.0004 < 0.0004 < 0.0004 < 0.0004
Nickel, mg/L 1 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01
Nitrate, ppm 23 n.d.b n.d.b n.d.b n.d.b n.d.b n.d.b 0.5
Nitrite, mg/L 10 < 0.02 < 0.02 < 0.02 < 0.02 < 0.02 < 0.02 < 0.02
pH 7.4 – 8.8 7.35 7.29 7.52 7.02 7.3 7.54 7.35
Phosphorus, ppm – 0.1 0.1 0.36 0.12 0.24 0.1 < 0.05
Potassium, ppm None 6.41 6.08 2.62 5.34 4.15 2.67 12.3
SARe – 0.4 0.6 0.6 0.7 0.7 0.8 4.3
Sodium, ppm None 15.9 34.8 29.2 64 36.2 29.4 229
Sulfate, ppm 1000 32 312 34 1,120 47 2 784
TDS, ppmf 3000 486 748 567 1,500 604 348 1,330
Zinc, ppm 50 < 0.01 < 0.01 0.02 0.03 0.29 0.05 0.03
a (CCME, 2008)
b  n.d., Not detected
c Conductivity- ability of water to pass an electrical current, increases with salinity
d Fecal coliforms – bacteria caused by presence of sewage contamination.
e Sodium absorption ratio – ratio of sodium to calcium and magnesium
f Total dissolved solids
* All values with a border exceed the recommended concentration level

 

Table A2.  Water flow rate recorded at the drinker in each pen (L/30 sec)  
Treatment
Item Water A Water B Water C SE P  
No. of observations 15 15 15 – –
Day 1 0.31 0.29 0.31 0.35 0.267
Wk 1 0.34 0.31 0.34 0.48 Trt = 0.092

Time < 0.0001

Trt*Time = 0.119
Wk 2 0.30ab 0.27b 0.33a
Wk 3 0.32 0.30 0.34
Wk 4 0.34 0.30 0.33
Wk 5 0.33 0.30 0.34
Wk 6 0.33 0.31 0.34
ab Means within a row with different superscripts differ (P < 0.05)  

 

Table A3.  Weekly bacterial counts of water from drinkers in WCROC nursery barn
Item Water Aa Water Bb Water Cc
Generic E. coli, MPN/100mL
   Initiald <1 8 1
   Wk 1 >2,400 >2,400 >2,400
   Wk 2 >2,400 687 687
   Wk 3 >2,400 126 >2,400
   Wk 4 142 >2,400 866
   Wk 5 >2,400 >2,400 >2,400
   Wk 6 >2,400 345 >2,400
Total Coliforms, MPN/100mL
   Initiald >2,400 2,420 26
   Wk 1 >2,400 >2,400 >2,400
   Wk 2 >2,400 >2,400 >2,400
   Wk 3 >2,400 >2,400 >2,400
   Wk 4 >2,400 >2,400 >2,400
   Wk 5 >2,400 >2,400 >2,400
   Wk 6 >2,400 >2,400 >2,400
Aerobic Plate Count, cfu/mL
   Initiald 139,000 115,000 1,194,000
   Wk 1 774,500 1,017,000 653,000
   Wk 2 745,000 640,000 720,000
   Wk 3 644,000 625,500 7,600,000
   Wk 4 3,345,000 2,200,000 1,670,000
   Wk 5 655,000 1,750,000 3,100,000
   Wk 6 760,000 1,140,000 2,100,000
a Water A samples pooled from pens: 6, 34, 57
b Water B samples pooled from pens: 3, 24, 42
c Water C samples pooled from pens: 11, 39, 62
d Initial sample was collected on the day pigs arrived (9/11/19) prior to pig placement

 

Figure A2.  Effect of water quality on average daily gain of nursery pigs over time

 

Figure A3.  Effect of water quality on average daily feed intake of nursery pigs over time

Figure A4.  Effect of water quality on gain efficiency of nursery pigs over time

Table A4.  Effect of water quality on percent of fecal dry matter (%) of nursery pigs  (Days 3 – 7 post-weaning) a
Treatment
Day postweaning Water A Water B Water C SE P
    4 68.68 70.06 68.00 1.62 Trt = 0.100

Time < 0.0001

Trt*Time = 0.920
    5 79.36 79.90 78.42
    6 72.93 77.18 73.07
    7 79.56 81.65 77.91
a Fecal grab samples were not collected on days 1 – 3 because pigs were not defecating enough for collection

 

Table A5.  Effect of water quality on intestinal integrity of nursery pigs
Treatment
Ratio Water A Water B Water C SE P
No. of observations 8 8 8 – –
Xylose/Rhamnose 2.97 1.99 2.39 0.457 0.337
Rhamnose/3-O-Methyl-Glucose 1.39 2.03 1.36 0.237 0.143
Xylose/3-O-Methyl-Glucose 3.67 3.64 3.03 0.557 0.655

 

Table A6.  Effect of differing water qualities on cytokine concentrations of nursery pigs (Day 8 of experiment)
Treatment
Item Water A Water B Water C SE P
No. of observations 15 15 15 – –
GM-CSF, pg/mL 1,605 1,748 1,566 – 1.000
IFNy, pg/mL 89,783 88,097 120,401 4,867 0.960
IL-1α, pg/mL 700 682 693 24 0.860
IL-1β, pg/mL 3,758 3,544 3,587 145 0.538
IL-1ra, pg/mL 7,201 7,059 6,383 329 0.223
IL-2, pg/mL 11,234 10,497 10,648 419 0.431
IL-4, pg/mL 118,032 115,685 120,401 8,464 0.931
IL-6, pg/mL 4,049 3,684 3,884 215 0.480
IL-8, pg/mL 523 535 445 31 0.101
IL-10, pg/mL 20,102 19,415 19,776 3,049 0.899
IL-12, pg/mL 3,246 3,353 3,442 117 0.845
IL-18, pg/mL 32,194 31,394 32,215 1,318 0.891
TNF, pg/mL 1,248 1,261 1,050 89 0.195

 

Table A7.  Effect of water quality on percentage (%) of total monocytes and granulocytes displaying phagocytosis in nursery pigs (Day 11 of the experiment)
Treatment
Item Water A Water B Water C SE P
No. of observations 8 8 8 – –
Total Monocytes 74.28 73.20 74.49 2.296 0.913
Total Granulocytes 95.27 93.56 93.79 0.967 0.451

 

Table A8.  Effect of differing water qualities on blood chemistry of nursery pigs (Day 8 of experiment)
Treatment
Item Water A Water B Water C SE P Ref. Rangesa
No. of observations 15 15 15 – – –
Glucose, mg/dL 103.2 103.9 105.8 2.93 0.803 57 – 113
AST, U/Lb 40.3 38 36.7 2.91 0.677 14 – 61
SDH, U/Lc 24.6 23.4 23 1.07 0.548 4.2 – 24.3
Bilirubin, mg/dL 0.35x 0.19xy 0.16y 0.05 0.03 0.0 – 0.4
Cholesterol, mg/dL 78 73 66.5 4.58 0.214 53 – 103
Total Protein, g/dL 4.2 4.4 4.2 0.19 0.792 4.0 – 8.4
Albumin, g/dL 3.1 3.1 3 0.09 0.536 2.0 – 4.4
Urea N, mg/dL 8.1 7.9 8.2 0.96 0.97 5 – 24
Creatinine, mg/dL 1.1 1 1 0.04 0.882 0.5 – 0.6
Phosphorus, mg/dL 8.5 8.5 8.4 0.18 0.903 5.3 – 11.1
Calcium, mg/dL 10.6 10.5 10 0.4 0.458 8.8 – 11.2
Potassium, mmol/dL 5.78 5.87 6.05 0.15 0.475 123 – 144
Sodium, mmol/dL 142 143 143 0.94 0.499 3.1 – 6.7
Chloride, mmol/dL 104 106 106 0.84 0.421 84 – 106
CK, U/Ld 240 382 332 70.05 0.354 129 – 1,409
Gamma-CT, U/L 25.98 23.22 24.25 2.13 0.65 23 – 62
Anion gap, mmol/L 19 19 18 0.82 0.444 10 – 27
Globulin, g/dL 1.4 1.3 1.3 0.05 0.203 1.6 – 4.9
A/G Ratio 2.3 2.4 2.4 0.12 0.599 –
Urea-Creatinine Ratio 7.5 7.6 7.8 0.78 0.955 –
Sodium-Potassium Ratio 24.7 24.5 23.6 0.55 0.307 –
Bicarbonate, mmol/dL 23 24 26 1.00 0.091 22 – 36
a Reference ranges of Marshfield Labs. Marshfield, WI.
b AST; aspartate aminotransferase
c SDH; sorbitol dehydrogenase
d CK; creatine kinase
xy Means within a row with different superscripts differ (P < 0.05).

 

Figure A5.  Effect of water quality on the average number of visits to the drinker per pig per hour over time (Days 1 – 3 post-weaning)

Figure A6.  Effect of water quality on the average time spent at the drinker per visit per hour over time (Days 1 – 3 post-weaning)