Water is an essential nutrient for broilers (NRC, 1994; Coon, 2002) and plays a critical role in metabolic function and body temperature maintenance. A number of studies have reported broiler water consumption (WC) requirements for various ages of broiler. The National Research Council (NRC) compiled WC data from a number of different studies raising broilers from five to nine weeks and summarized weekly WC values for broilers grown up to 8 wks with the caveat that WC data from these studies varied depending on ambient temperature, diet, growth rate, and equipment (NRC, 1994). Gardiner and Hunt (1984) was the only study referenced that raised broilers to 9 wks. However, 9 wk WC was not included by the NRC (1994). Tabler et al. (2008) monitored total flock WC over a ten-year period (1995 to 2005) for broilers raised in two tunnel-ventilated houses measuring 12 × 152 m. Broiler ages for the 17 flocks monitored ranged from 39 to 57 d with average harvest weights between 1.68 and 2.85 kg. Average cumulative flock WC over the ten-year period was between 163,182 and 165,040 L for the two houses. A study conducted by Williams et al. (2013) aimed to identify differences in WC between three test periods (1991, 2000 to 2001, and 2010 to 2011) for broilers raised under commercial conditions in four commercial-style houses measuring 12 × 122 m. Daily water consumption was recorded for broilers grown to 6 wks. Results suggested that cumulative WC has significantly increased by approximately 1,980 L/1,000 birds over the 20-yr test period and water requirements outlined by NRC (1994) may no longer reflect the water needs of broilers. Advancements in drinking systems also played a role in significantly reducing broiler WC as the industry transitioned from open waterers to closed nipple-type drinkers. Using these closed drinking systems also resulted in a reduction of in-house ammonia and drier bedding under the drinker lines (Elwinger and Svensson, 1996).
There is, however, a lack of information within the literature regarding broilers grown to 9 wks with target weights of 4.1 kg. Therefore, the objective of this study was to quantify WC for broilers raised to 9 wks under commercially relevant conditions.
Methods and materials
All procedures relating to the use of live birds in this study were approved by the USDA ARS Animal Care and Use Committee at the Mississippi State location. Two trials (Flock 1 and Flock 2) were conducted in a tunnel-ventilated research facility at the USDA Poultry Research Unit in Starkville, MS. Both flocks were raised in the same house where Flock 1 was reared from Jan. 7 to Mar. 9, 2020, and Flock 2 was reared from Aug. 2 to Oct. 3, 2021. Water and feed were provided ad libitum for both trials. Mortality checks were made twice daily and recorded for each pen. Deceased birds were not replaced in order to match commercial practices.
Broiler housing
For each flock, a total of 2,160 Ross 708 straight-run broiler chicks were obtained from a commercial hatchery and randomly distributed across eight pens (n=8) at 270 birds/pen. Birds were grown from hatch to 63 d with target weights of 4.1 kg/bird. Pen dimensions were 2.9 × 9.1 m to satisfy stocking density recommendations from the National Chicken Council (NCC) of 44 kg/m2 for birds grown to more than 3.4 kg (NCC, 2020). Floor bedding consisted of 15 cm of pine shavings. Flock 1 was reared on new shavings whereas Flock 2 litter was de-caked and top dressed with new shavings prior to placement.
Pens mimicked a commercial housing setup with a mechanical auger feedline system installed in the center of the pen (Fig. 1, left). Feedline hopper capacity was approximately 68 kg and was filled manually. Six feed pans were installed following primary breeder recommendations of no more than 45 birds per pan for bird weights exceeding 3.5 kg (Aviagen, 2018). All feeders were set to provide the maximum allowable amount of feed. Chick starters (Kwik Start Chick Starters, Grower Select, Newton Grove, NC) were installed along the feedlines to provide supplemental feed during the first seven days. Birds for each trial were provided with a four-phase diet that met or exceeded NRC recommendations (NRC, 1994) consisting of a starter (1 to 16 d), grower (17 to 28 d), finisher (29 to 42 d), and withdrawal (43 to 63 d). Diet composition is shown in Table 1. Feed intake (FI; g/bird) was monitored using four load cells attached to the four drop cables supporting each feedline: two at the hopper, one in the center of the feedline, and one at the feedline motor. Feedline load cell systems were calibrated at the beginning of each flock and tared prior to bird placement. Added feed was recorded for each pen and during diet changes, feed was completely removed from the feedlines, weighed and recorded, before the next diet was added. Feedlines were not fully suspended until d 12 as feed pans were still in flood mode, therefore flock FI reported in this study represents FI from d 12 to 63. Broiler body weights (BW; g/bird) were recorded at d 0, 7, 14, 21, 28, 35, 42, 49, 56, and 63 for each pen. Placement weights included the whole pen (270 birds), and subsequent BW checks represented 5% of the flock placement for each pen (14 birds), exceeding the recommendation of weighing a minimum of 1% of the flock made by Aviagen (2019). Both FI and BW were used to determine overall flock feed conversion ratio (FCR; g FI/ g BW) evaluated from 2 wks to 9 wks.
Fig. 1. (left) Two water lines were installed on either side of a mechanical auger feed line. (right) Water tanks with a capacity of 37.8 L were installed 1.4 m above the pen floor and supplied water to two drinker lines.
Table 1. Composition of each diet (starter, grower, finisher, and withdrawal) ration on % by weight basis.
| Ingredient | Starter | Grower | Finisher | Withdrawal |
|---|---|---|---|---|
| Empty Cell | (%) | (%) | (%) | (%) |
| Corn | 56.17 | 61.54 | 64.94 | 63.56 |
| Soy | 32.36 | 27.45 | 25.65 | 25.82 |
| Poultry fat | 3.17 | 3.03 | 3.56 | 4.69 |
| Poultry-by-product | 5.00 | 5.00 | 2.99 | 3.00 |
| Dicalcium phosphate | 1.27 | 1.04 | 1.01 | 0.96 |
| Calcium carbonate | 0.99 | 0.89 | 0.86 | 0.85 |
| Sodium chloride | 0.47 | 0.48 | 0.47 | 0.50 |
| Methionine | 0.22 | 0.17 | 0.15 | 0.21 |
| Vitamin and mineral premix1 | 0.25 | 0.25 | 0.25 | 0.25 |
| Zoamix | – | 0.05 | 0.05 | 0.04 |
| Lysine | 0.03 | – | – | 0.01 |
| BMD-50 | – | 0.05 | – | – |
| L-Threonine | – | – | 0.02 | – |
| Choline | – | – | – | 0.05 |
- 1
-
Vitamin and mineral premix supplied per kilogram of diet: retinol, 7,716 IU; cholecalciferol, 2,756 IU; tocopherol acetate, 17 IU; cyanocobalamin, 0.011 mg; menadione, 0.83 mg; riboflavin, 6.61 mg; pantothenic acid, 6.61 mg; thiamine, 1.10 mg; niacin, 27.6 mg; pyridoxine, 1.38 mg; folic acid, 0.69; biotin, 0.03 mg; choline, 386 mg; Mn (manganese sulfate), 100 mg; Zn (zinc sulfate), 100 mg; Fe (ferrous sulfate), 50 mg; Cu (copper chloride and sulfate), 11.3 mg; Se (sodium selenite), 0.15 mg; I (calcium iodate), 1.5 mg
Two Plasson commercial drinker lines using the grey nipple system and drip trays (Plasson, Diversified, Eatontown, NJ) were installed according to manufacturer specifications (Plasson, 2017a) on either side of the feedline (Fig. 1, left). Nipple spacing was 15 cm and nipple density followed primary breeder recommendations of 9 birds per nipple for bird weights exceeding 3 kg (Aviagen, 2018). Water was gravity-fed to drinker lines from a 38 L capacity water barrel installed approximately 1.4 m above the floor of each pen (Fig. 1, right). An Omron programmable relay (ZEN-20C1DR-D-V2, Omron Corp., Hoffman Estates, IL) was used to operate a solenoid valve installed on the main water trunk line to supply water to each tank above the pen. The valve was operated every 3 hrs each day of the trial with a fill time of 4 min. Float valves were installed on the water barrels to avoid overflow during filling events. Water line pressure was monitored daily via water line site tube and adjusted according to manufacturer operation instructions (Plasson, 2017b). Both water line and feed pan heights were monitored daily and adjusted according to primary breeder recommendations (Aviagen, 2018).
The housing environment was maintained using an electronic environmental controller (EDGE 1, Cumberland GSI, Assumption, IL). House temperature, lighting intensity, photoperiod, and minimum ventilation followed the schedule shown in Table 2, representing common environmental settings used in the industry. Minimum ventilation followed National Poultry Technology Center (NPTC) guidelines based on bird age (Campbell et al., 2014). Round radiant brooders were used to maintain house floor temperatures using a prescribed temperature curve. Minimum ventilation fans were operated off a timer according to an airflow per bird requirement (Table 2).
Table 2. Prescribed temperature, lighting schedule, minimum ventilation settings, and water line flow rate.
| Broiler Age | House Temperature | Light Intensity | Photoperiod | Minimum Ventilation | Water line Flow Rate1 |
|
|---|---|---|---|---|---|---|
| (d) | (°C) | (lux) | (L:D) | (m3/s/bird) | (mL/min) | |
| Empty Cell | Empty Cell | Empty Cell | Empty Cell | Empty Cell | Flock 1 | Flock 2 |
| 1 | 32.2 | 30 | 23:1 | 0.42 | 64 | 64 |
| 4 | 31.1 | 30 | 23:1 | 0.42 | 64 | 64 |
| 8 | 28.9 | 10 | 20:4 | 0.42 | 64 | 64 |
| 14 | 26.7 | 10 | 20:4 | 0.59 | 64 – 70 | 64 – 76 |
| 21 | 23.9 | 10 | 20:4 | 0.59 | 64 – 76 | 70 – 95 |
| 28 | 21.1 | 5 | 18:6 | 1.10 | 70 – 95 | 76 – 109 |
| 35 | 18.3 | 5 | 18:6 | 1.10 | 76 – 109 | 95 – 106 |
| 42 | 18.3 | 5 | 18:6 | 1.53 | 95 – 160 | 109 – >193 |
| 61 | 18.3 | 5 | 23:1 | 1.53 | 95 – 160 | 109 – >193 |
- 1
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Recommended water flow rate for Plasson grey nipple system (Plasson, 2023).
Water data collection
Water weight data were collected every minute using a datalogger (CR1000X, Campbell Scientific, Logan, UT) and daily values were evaluated from 04:00 to 03:59. Water weights were measured using scales (Defender D50RQR, Ohaus, Parsippany, NJ) with a maximum capacity of 50 kg. Daily water weights (kg) were computed, and daily WC presented as L/1,000 birds with adjustments made for daily pen mortality. Delays in water scale installation prevented capture of WC data from d 1 to 7 for Flock 1, therefore daily WC was evaluated from d 8 to 63 for each flock. An equipment malfunction due to inclement weather resulted in an 8-h gap (6:00 to 14:00) in WC data on d 23 during Flock 1. Data for this d was still presented and included in cumulative WC for this flock, but the drop in WC at d 23 was noted due to equipment malfunction.
Statistical analysis
The study was a completely randomized design with two treatments (Flock 1 and Flock 2) where pen (n=8) was considered the experimental unit. Pens within each flock were under common conditions. Daily WC for each treatment was measured from d 8 to 63. Mean daily, weekly, and cumulative WC data were analyzed in SAS (Version 9.4, SAS Institute Inc., Cary, NC) using the GLIMMIX procedure. Body weight was included as a covariate for the weekly and cumulative WC comparison. Least square means between Flock 1 and Flock 2 were separated using the Tukey-Kramer procedure where statistical significance was considered at P < 0.05, and 0.05 ≤ P ≤ 0.10 were considered a trend. Differences in daily mean WC between flocks were evaluated for each day from d 8 to 63. Comparisons for weekly mean WC were evaluated from 2 to 9 wks.
Results and discussion
Bird performance
Flock 1 mortality (3.7%) was lower compared to Flock 2 (4.6%). Flock 1 BW was significantly greater at d 0 (P < 0.0001) and for wks 2 to 9 (P < 0.0007) compared to Flock 2 (Table 3). Both flocks exceeded the target weight of 4.1 kg at wk 9, however Flock 1 (5,154 g/bird) was approximately 933 g/bird heavier than Flock 2 (4,221 g/bird). Elevated environmental temperatures likely contributed to lower Flock 2 BW, similar to observations made by Smith (1993) and Donkoh (1989) for broilers raised under high environmental temperatures. However, these lower Flock 2 BW were likely exacerbated by a challenge associated with a spike in mortality at 2 wk. Observations of smaller broilers prompted the attending veterinarian to submit two birds from each pen to the Mississippi State University (MSU) College of Veterinary Medicine Diagnostic Laboratory Services for necropsy. The primary finding was Flock 2 exhibited symptoms of runting-stunting syndrome (RSS) characterized by poor flock uniformity, depressed growth, and decreased feed consumption (Shivaprasad, 2013). It was also noted that four of the sixteen chicks submitted for necropsy had septicemia due to E. coli infection.
Table 3. Comparison of weekly mean broiler body weight (BW) between Flock 1 and 2 from placement (wk 0) to 9 wks.
| Broiler | Flock 11,3,4 | Flock 22,4 | Empty Cell | Empty Cell |
|---|---|---|---|---|
| Age | BW | BW | SEM | P-value |
| (d) | (g/bird) | (g/bird) | (g/bird) | Empty Cell |
| 0 | 41 a | 39 b | 0.31 | <0.0001 |
| 7 | 174 a | 167 a | 2.71 | 0.0842 |
| 14 | 478 a | 432 b | 7.50 | 0.0007 |
| 21 | 960 a | 799 b | 10.80 | <0.0001 |
| 28 | 1,643 a | 1,410 b | 24.33 | <0.0001 |
| 35 | 2,312 a | 1,993 b | 30.30 | <0.0001 |
| 42 | 3,166 a | 2,659 b | 34.56 | <0.0001 |
| 49 | 3,884 a | 3,339 b | 63.37 | <0.0001 |
| 56 | 4,549 a | 4,066 b | 48.26 | <0.0001 |
| 63 | 5,154 a | 4,221 b | 22.95 | <0.0001 |
- 1
-
Values represent the mean of 8 replicate pens placed on January 7 (winter flock).
- 2
-
Values represent the mean of 8 replicate pens placed on August 2 (late summer flock).
- 3
-
Means within a row lacking a common superscript are significantly different (P<0.05).
- 4
-
Plasson grey nipple system with trays were used; Ross 708 straight-run broilers.
Total FI was 8,591 and 7,748 g/bird for Flock 1 and Flock 2, respectively. Feed conversion ratio was 1.72 g FI/g BW for Flock 1 and 1.90 g FI/g BW for Flock 2. Compared to as-hatched FI (8,747 g/bird) and FCR (2.1 g FI/g BW) for Ross 708 broilers (Aviagen, 2019), FI was 156 and 999 g/bird less for Flock 1 and Flock 2 and FCR was lower for both flocks.
Daily water consumption
Mean daily and cumulative WC for Flock 1 and 2 are summarized in Table 4. In general, daily WC increased with broiler age consistent with similar trends observed in the literature (Pesti et al., 1985; Brake et al., 1992; Bruno et al., 2011; Williams et al., 2013). There was a notable reduction in daily WC between d 55 and 58 for Flock 1 that coincided with a disease event identified by the attending veterinarian on d 56. Based on mortality necropsy results, gangrenous dermatitis was identified. A medication regimen was started on d 56 until the end of the flock. Four days after medication was provided daily WC began to increase, likely signaling birds were recovering from the disease event, but did not recover to values observed prior to the disease event before the end of the study. This drop in daily WC during the disease event was consistent with trends reported by Butcher et al. (1999) and Manning et al. (2007) where decreased daily WC can be an indicator of a disease outbreak. Peak daily WC was observed near the end of Flock 1 (437 L/1,000 birds/d) and Flock 2 (405 L/1,000 birds/d) at d 53 and 61, respectively. Flock 1 tended to consume significantly more water (P < 0.05) than Flock 2 on d 8, 10 to 22, 24 to 55, 57, 58, 62, and 63. Only WC on d 58 for Flock 2 (378 L/1,000 birds/d) was significantly greater (P = 0.0007) than Flock 1 (329 L/1,000 birds/d). While cumulative WC was greater for Flock 1 (15,276 L/1,000 birds) compared to Flock 2 (13,982 L/1,000 birds), differences in means between the two flocks were not significant (P = 0.4178).
Table 4. Comparison of daily mean water consumption (WC) from d 8 to 63 for Flock 1 and Flock 2.
| Broiler | Flock 11,3,5 | House4 | Flock 22 | House4 | SEM | P-value |
|---|---|---|---|---|---|---|
| Age | WC | Temperature | WC | Temperature | Empty Cell | Empty Cell |
| (d) | (L/1,000 birds) | (°C) | (L/1,000 birds) | (°C) | (L/1000 birds) | Empty Cell |
| 8 | 72 a | 28.0 | 61 b | 30.7 | 3.12 | 0.0230 |
| 9 | 74 a | 27.3 | 70 a | 30.7 | 1.89 | 0.1053 |
| 10 | 88 a | 25.6 | 77 b | 29.6 | 1.46 | 0.0002 |
| 11 | 96 a | 26.5 | 82 b | 29.0 | 2.06 | 0.0005 |
| 12 | 109 a | 26.8 | 90 b | 28.6 | 1.58 | <0.0001 |
| 13 | 124 a | 26.1 | 101 b | 28.8 | 1.52 | <0.0001 |
| 14 | 134 a | 25.6 | 104 b | 27.6 | 1.48 | <0.0001 |
| 15 | 156 a | 24.4 | 105 b | 27.2 | 6.07 | <0.0001 |
| 16 | 166 a | 24.0 | 110 b | 28.1 | 3.61 | <0.0001 |
| 17 | 157 a | 24.0 | 115 b | 27.8 | 2.96 | <0.0001 |
| 18 | 164 a | 24.0 | 138 b | 26.5 | 7.59 | 0.0296 |
| 19 | 173 a | 24.1 | 111 b | 26.2 | 2.66 | <0.0001 |
| 20 | 182 a | 24.7 | 122 b | 27.5 | 2.21 | <0.0001 |
| 21 | 192 a | 24.7 | 130 b | 27.9 | 2.72 | <0.0001 |
| 22 | 197 a | 22.9 | 135 b | 27.4 | 3.14 | <0.0001 |
| 23 | 121 * | 22.3 | 147 | 27.2 | 2.23 | – |
| 24 | 212 a | 22.1 | 154 b | 27.1 | 3.19 | <0.0001 |
| 25 | 207 a | 22.4 | 160 b | 26.3 | 2.16 | <0.0001 |
| 26 | 225 a | 22.2 | 169 b | 26.0 | 3.72 | <0.0001 |
| 27 | 231 a | 23.0 | 184 b | 26.1 | 4.02 | <0.0001 |
| 28 | 236 a | 23.4 | 186 b | 25.1 | 3.25 | <0.0001 |
| 29 | 225 a | 22.1 | 184 b | 24.3 | 3.75 | <0.0001 |
| 30 | 229 a | 22.1 | 174 b | 24.1 | 4.40 | <0.0001 |
| 31 | 251 a | 20.4 | 198 b | 24.8 | 5.31 | <0.0001 |
| 32 | 254 a | 20.3 | 210 b | 23.9 | 2.04 | <0.0001 |
| 33 | 284 a | 20.5 | 225 b | 23.4 | 2.84 | <0.0001 |
| 34 | 295 a | 20.8 | 234 b | 23.9 | 3.16 | <0.0001 |
| 35 | 282 a | 21.0 | 255 b | 24.6 | 3.06 | <0.0001 |
| 36 | 294 a | 19.0 | 258 b | 23.0 | 5.23 | 0.0003 |
| 37 | 297 a | 19.3 | 263 b | 24.0 | 4.34 | <0.0001 |
| 38 | 311 a | 18.2 | 274 b | 23.4 | 4.41 | <0.0001 |
| 39 | 326 a | 17.7 | 279 b | 21.8 | 3.26 | <0.0001 |
| 40 | 333 a | 17.9 | 283 b | 21.6 | 3.09 | <0.0001 |
| 41 | 349 a | 18.3 | 291 b | 22.4 | 4.17 | <0.0001 |
| 42 | 358 a | 18.9 | 308 b | 24.1 | 4.71 | <0.0001 |
| 43 | 340 a | 19.5 | 289 b | 24.2 | 5.43 | <0.0001 |
| 44 | 372 a | 18.1 | 323 b | 23.7 | 5.06 | <0.0001 |
| 45 | 378 a | 18.0 | 324 b | 22.4 | 4.02 | <0.0001 |
| 46 | 376 a | 17.6 | 346 b | 23.5 | 4.60 | 0.0005 |
| 47 | 392 a | 17.7 | 349 b | 24.9 | 4.57 | <0.0001 |
| 48 | 410 a | 18.0 | 353 b | 23.9 | 6.65 | <0.0001 |
| 49 | 418 a | 18.5 | 364 b | 24.3 | 6.65 | <0.0001 |
| 50 | 388 a | 18.9 | 354 b | 24.1 | 4.94 | 0.0002 |
| 51 | 414 a | 18.2 | 345 b | 23.4 | 5.59 | <0.0001 |
| 52 | 426 a | 18.0 | 368 b | 20.2 | 4.72 | <0.0001 |
| 53 | 437 a | 18.1 | 360 b | 19.8 | 6.70 | <0.0001 |
| 54 | 436 a | 18.4 | 369 b | 20.1 | 6.36 | <0.0001 |
| 55 | 422 a | 19.1 | 380 b | 20.7 | 6.24 | 0.0003 |
| 56 | 389 a | 20.6 | 392 a | 21.2 | 5.62 | 0.7461 |
| 57 | 404 a | 21.0 | 377 b | 21.9 | 8.69 | 0.0421 |
| 58 | 329 a | 18.4 | 378 b | 22.6 | 6.07 | <0.0001 |
| 59 | 359 a | 18.5 | 374 a | 22.8 | 10.35 | 0.3229 |
| 60 | 376 a | 18.3 | 384 a | 22.5 | 7.88 | 0.4520 |
| 61 | 429 a | 18.0 | 405 b | 23.2 | 7.26 | 0.0390 |
| 62 | 417 a | 18.8 | 357 b | 23.1 | 7.47 | <0.0001 |
| 63 | 406 a | 19.6 | 367 b | 22.8 | 6.56 | 0.0009 |
| WCCumulative | 15,276 a | 13,982 a | 779 | 0.4178 |
- 1
-
Values represent the mean of 8 replicate pens placed on January 7 (winter flock).
- 2
-
Values represent the mean of 8 replicate pens placed on August 2 (late summer flock).
- 3
-
Means within a row lacking a common superscript are significantly different (P<0.05).
- 4
-
Daily mean house temperature.
- 5
-
A decrease in Flock 1 WC was observed between d 55 and 58, attributed to a disease event.
- ⁎
-
The observed drop in WC on d23 for flock 1 was due to a loss of power to the water scales.
Water consumption tends to increase when broilers are exposed to elevated temperatures (Lacy, 2002; Donkoh, 1989) and there was an expectation that Flock 2 (late summer) WC would exceed Flock 1 (winter) WC. This is due to the warmer seasonal temperatures that broilers grown in Flock 2 would likely experience. However, this was not observed even when maximum daily outside temperatures ranged from 24 to 32°C during Flock 2 compared to 4 to 24°C during Flock 1. Daily mean house temperatures during Flock 2 routinely exceeded those of Flock 1 (Table 4) throughout the growth period. From wks 3 to 9 of Flock 2, daily mean house temperatures were between 1.5 to 6.6°C higher than temperature set-points. A probable explanation of depressed WC during these warmer conditions was poor chick quality and an RSS disease challenge during the first two weeks of Flock 2 discussed earlier.
Weekly water consumption
Weekly WC was evaluated from 2 to 9 wks for each flock and summarized in Table 5. Peak weekly WC was observed at wk 8 for Flock 1 (2,884 L/1,000 birds/wk) and wk 9 for Flock 2 (2,689 L/1,000 birds/wk). Flock 2 consumed less water for wks 2 to 8 (P < 0.0373) compared to Flock 1. Weekly consumption during this seven-week period for Flock 2 was between 93 and 328 L/1,000 birds less than Flock 1. There was no significant difference in weekly Flock 1 (2,673 L/1,000 birds/wk) and Flock 2 (2,689 L/1,000 birds/wk) WC during wk 9 which coincided with the disease event during Flock 1.
Table 5. Comparison of weekly mean water consumption (WC) between Flock 1 and Flock 2 in addition to results reported by Williams et al. (2013) for broilers grown between 2010 and 2011.
| Broiler | Flock 11,3,4,6 | Flock 22,4 | Empty Cell | Empty Cell | Williams et al. (2013)5 |
|---|---|---|---|---|---|
| Age | WC | WC | SEM | P-value | Empty Cell |
| (wk) | (L/1,000 birds) | (L/1,000 birds) | (L/1,000 birds) | Empty Cell | (L/1,000 birds) |
| 1 | – | – | – | – | 269 |
| 2 | 687 a | 594 b | 11.14 | 0.0003 | 728 |
| 3 | 1,172 a | 859 b | 42.99 | 0.0021 | 1,142 |
| 4 | 1,446 a | 1,118 b | 26.30 | <0.0001 | 1,536 |
| 5 | 1,773 a | 1,529 b | 28.89 | 0.0005 | 1,907 |
| 6 | 2,231 a | 1,990 b | 54.87 | 0.0373 | 2,171 |
| 7 | 2,629 a | 2,402 b | 43.67 | 0.0117 | – |
| 8 | 2,884 a | 2,593 b | 52.37 | 0.0090 | – |
| 9 | 2,673 a | 2,689 a | 273.81 | 0.9777 | – |
- 1
-
Values represent the mean of 8 replicate pens placed on January 7 (winter flock).
- 2
-
Values represent the mean of 8 replicate pens placed on August 2 (late summer flock).
- 3
-
Means within a row lacking a common superscript are significantly different (P < 0.05).
- 4
-
Plasson grey nipple system with trays were used; Ross 708 straight-run broilers.
- 5
-
Ziggity nipple drinker system without trays were used; Cobb straight-run broilers.
- 6
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A decrease in Flock 1 WC was observed between d 55 and 58, attributed to a disease event.
A comparison of weekly mean WC from this current study and results reported in the literature is shown in Fig. 2. Values reported in the literature were converted to L/1,000 birds/wk to make equivalent comparisons. An equation presented by Xin et al. (1994) for daily water use (DWU) was used to determine weekly WC for broilers grown up to 8 weeks. Consumption values from this current study were generally greater than WC values reported by Gardiner and Hunt (1984), Pesti et al. (1985), Xin et al. (1994), and NRC (1994). Only Gardiner and Hunt (1984) reported data for broilers grown to 9 wks where cumulative WC between wks 2 to 9 (11,618 L/1,000 birds) was 31% and 20% less than cumulative WC compared to Flock 1 and 2, respectively, for the same period. Williams et al. (2013) noted bird WC has increased over the previous 20 years based on data collected for three flocks grown during 1991, 2000 to 2001, and 2010 to 2011. Based on their findings there was an expectation that WC would likely have increased in this current study, however that was not observed. Comparisons between weekly WC (wks 2 to 6) reported by Williams et al. (2013) for broilers grown from 2010 to 2011 and results from this study were compiled to identify any changes in broiler WC (Table 5). Weekly WC for Flocks 1 and 2 were consistently less than values reported by Williams et al. (2013). Flock 2 weekly consumption was between 8% and 27% less than values reported by Williams et al. (2013). The only observed increases in WC occurred during Flock 1 where consumption was 3% greater during wk 3 and 6. Total consumption over the 5-wk period was 35 and 1,254 L/1,000 birds less than Williams et al. (2013) for Flocks 1 and 2, respectively. Given this data, results suggest broiler WC has not increased through 42 d since the study conducted by Williams et al. (2013) in 2010 and 2011. However, this extends only to 42 d and does not encompass the most pronounced separation in WC at wk 8 from this study compared to data reported in the literature. Based on data from Fig. 2, birds at wk 8 in Flock 1 consumed 46% and 40% more water than Xin et al. (1994) and Gardiner and Hunt (1984), respectively. Similarly, birds at wk 8 in Flock 2 consumed 31% and 27% more water compared to Xin et al. (1994) and Gardiner and Hunt (1984), respectively. While this represents a large increase in WC, broilers from this study were also much heavier.
Fig. 2. Comparison of mean weekly water consumption (WC; L/1,000 birds) for Flock 1 and Flock 2 of this study to those reported in the literature. Note the asterisk denotes a disease event that occurred during week 8 for Flock 1 and resulted in lower water consumption for week 9. 1Circular waterers; Ross × Arbor Acre broiler males. 2Used mini-drinkers for the first 7d then replaced with trough-type waterers; Broiler strain was not specified. 3Data was compiled from a number of studies using a range of watering systems (mini-drinkers, trough drinkers, circular waterers, chick founts); Broiler strain varied (Cobb, Hubbard, Ross × Arbor Acre). 4Nipple drinkers; Cobb × Cobb broiler males. 5Data presented for Williams et al. (2013) was for broilers raised between 2010 and 2011. Ziggity nipple drinkers without trays; Cobb straight-run broilers. 6Each data point for Flock 1 and 2 represents means of 8 replicate pens. Plasson grey nipple drinkers with trays; Ross 708 straight-run broilers.
Water consumption based on bird weight
The practice of reporting WC values in terms of L/1,000 birds has been valuable when discussing broiler WC needs with producers as it is easy to calculate water needs for a given size house, however from a research perspective, discussions based on broiler BW are warranted because of improvements in broiler genetics. A comparison of BW data is shown in Fig. 3. Bird weight data reported by Gardiner and Hunt (1984) was limited to 4, 7, and 9 wks for male Ross × Arbor Acre broilers. Equations presented by Xin et al. (1994) for live body weight (LBW) for male Cobb × Cobb strain broilers grown to 8 wks were used to determine weekly BW. Bird weights were not recorded by Williams et al. (2013), therefore as-hatched performance objective data for Cobb strain broilers was used (Cobb, 2008) to closely match the Cobb strain broilers raised between 2010 and 2011.
Fig. 3. Comparison of broiler body weight (BW; g/bird) for Flock 1 and Flock 2 of this study to those reported in the literature. 1Circular waterers; Ross × Arbor Acre broiler males. 2Nipple drinkers; Cobb × Cobb broiler males. 3Cobb (2008) as-hatched performance data was used to represent BW not reported by Williams et al. (2013). Ziggity nipple drinkers without trays; Cobb straight-run broilers. 4Each data point for Flock 1 and 2 represents means of 8 replicate pens. Plasson grey nipple drinkers with trays; Ross 708 straight-run broilers.
Flock 2 mean BW at placement (39 g/bird) was 3 g less than both Flock 1 (41 g/bird) and Cobb (2008) (41 g/bird). Xin et al. (1994) reported a heavier placement weight of 52 g/bird for the male broilers used in their study. Flock 1 and 2 BW was consistently greater than those reported by Gardiner and Hunt (1984). Final bird weights at d 63 were 1,460 and 527 g/bird heavier for Flocks 1 and 2, respectively, compared to 63 d BW reported by Gardiner and Hunt (1984) (3,694 g/bird). Broiler weights for Flocks 1 and 2 were 50 to 70% heavier at d 56 compared to BW reported by Xin et al. (1994) (2,681 g/bird). Broilers raised during this study achieved similar final BW reported by Xin et al. (1994) between 35 to 42 days (2 to 3 weeks earlier). Differences were less pronounced comparing BW data from this study and data reported by Cobb (2008). Flock 2 BW tended to be less than that of Cobb (2008). At d 42, Flock 2 BW was 4% less than Cobb (2008) (2,764 g/bird). However, Flock 1 BW was 15% greater (3,166 g/bird) at d 42 compared to broilers grown in 2008 and achieved a similar final bird weight three to four days sooner. Between improved genetics and improved housing systems, broilers are achieving heavier BW earlier in the flock compared to 10, 30, and 40 years ago.
The ratio of WC to BW (WC:BW; mL of water per kg BW) was computed on a daily basis (Fig. 4). Gardiner and Hunt (1984) did not report daily WC and was therefore excluded from this comparison. The daily WC:BW ratio ranged between 80 to 280 mL/kg/d for Flock 1 and between 90 to 240 mL/kg/d for Flock 2 from d 14 to d 63 and tended to decrease as broilers aged. Compared to WC:BW synthesized from WC and BW data in the literature, Flock 1 and 2 tended to have a lower WC:BW ratio, suggesting broilers are consuming less water per kilogram of BW than they were 10 to 30 yrs ago. At d 42, daily WC:BW was similar for Williams et al. (2013) (115 mL/kg/d), Flock 1 (113 mL/kg/d), and Flock 2 (116 mL/kg/d), however, data from Xin et al. (1994) showed approximately 32 to 35 mL more water per kg of bird-weight for the same day (148 mL/kg/d). At d 56, the difference in WC:BW between Xin et al. (1994) and Flocks 1 and 2 were less pronounced. The WC:BW at d 56 for Xin et al. (1994) was 105 mL/kg/d compared to 86 mL/kg/d and 96 mL/kg/d for Flocks 1 and 2, respectively. Broilers at 63 d raised under the conditions outlined in this paper had the lowest WC:BW of 79 and 87 mL/kg/d for Flocks 1 and 2, respectively.
Fig. 4. Comparison of daily water consumption-to-bird weight ratio (WC:BW; L of water/kg of BW) for Flock 1 and Flock 2 of this study to those synthesized from WC and BW data reported in the literature. Note the asterisk denotes a disease event that occurred during week 8 for Flock 1 and resulted in lower water consumption for week 9. 1Nipple drinkers; Cobb × Cobb broiler males. 2Ziggity nipple drinkers without trays; Cobb straight-run broilers. 3Each data point for Flock 1 and 2 represents means of 8 replicate pens. Plasson grey nipple drinkers with trays; Ross 708 straight-run broilers.
Improving future water consumption comparisons
It can be difficult to make comparisons between WC needs in the literature and attributing those changes to factors in an industry that is continuously improving broiler genetics and housing systems, modifying diets, and adjusting environmental management practices based on recommendations from the most updated research. This is particular true considering the transition in water drinking equipment from open bell drinkers to closed nipple drinking systems in commercial broiler production. A number of studies have demonstrated WC to be significantly less when using nipple drinking systems compared to bell drinkers (May et al, 1997; Bruno et al. 2011). The industry has moved towards nipple drinking systems because of the reduction in water spillage that contributed to high ammonia levels and degradation of litter near drinker lines and less bacterial contamination compared to an open bell or trough waterer.
As shown in Fig. 3, bird BW continues to increase over time for equivalent days of age. To make valid WC comparisons, it will be important to report weekly BWs in addition to bird numbers and adjust WC data based on mortalities. The use of performance objectives to estimate BW does not account for differences that a flock may experience with diet, the thermal environment, and other factors. Other important information to report on a weekly or scheduled basis would be environmental set-points, in-house mean temperature, lighting photoperiod and intensity, diet composition by feeding phase, drinking systems and water line pressures. In reviewing the literature, it is typical that one or more of these pieces of information is not recorded. Doing so would provide a better understanding of the growing conditions of broilers and how these parameters may affect WC.
Conclusions and applications
- 1)
Broiler WC varied on a daily basis and increased with broiler age. Mean cumulative WC for broilers grown to a target weight of 4.1 kg in 63 days was 14,629 L/1,000 birds, ranging from 13,982 to 15,276 L/1,000 birds.
- 2)
At wk 8, flocks from this study consumed between 27% to 46% more water on a L/1,000 birds/wk basis than data reported 20 to 30 yrs ago. However, broilers in this study consumed less water to achieve equivalent BW when compared to past studies that reported broiler WC and BW. While reporting broiler WC in units of L/1,000 birds makes discussions in the field easier when trying to estimate the expected water needs of a farm, broiler genetics and husbandry practices continue to improve. This leads to larger birds earlier in the flock compared to previous generations. Including a WC:BW in terms of mL of WC to kg of BW can provide a more accurate comparison.
- 3)
Future research studies concerning broiler WC should include additional data to allow for better comparisons between studies: weekly BW, environmental set-points, in-house air temperature, lighting photoperiod and intensity, diet composition by feeding phase, drinking systems and water line pressures, to name a few.
Source: Science Direct
