Water is often overlooked as a nutrient.
Yet water plays an important role in many body functions. It is required for digestion and metabolism of nutrients and aids the transit of feed through the digestive tract. Water supports blood flow and waste product removal. Additionally, the unique features of water make it a vital part of body temperature regulation.
The importance of water is clearly visible after feed cleanup when birds flock to the nipple lines to drink. For that reason, calculate around 10 birds per nipple with sufficient water pressure. With correct water pressure, the drip cups below the nipples are moist or wet. Insufficient water pressure or volume, an overly strict water restriction program, or rearing houses that are too dark (<0.5 lux) can considerably reduce the water intake. Insufficient water intake will hinder digestion and ultimately have a negative effect on growth rate and body weight uniformity.
To support water balance, three forms of water are available to the chicken: preformed water from the drinker lines (75 % of need), bound water in the feed (7.5 to 10 % of need) and metabolic water created by the body during oxidation of nutrients (15 to 25% of need). Water intake can be altered by the feed formula in two ways: adjusting the protein level or the electrolyte concentrations.
Water and Protein
The protein level has a direct effect on the water consumption. High protein feeds will reduce the production of metabolic water but also increase the amount of water required to excrete excess nitrogen. Therefore a higher protein diet generally leads to higher water consumption.
Water and Electrolytes
Adjusting electrolyte balance can be calculated several ways, but the methods are difficult to use in practice. To start, it is best to keep things easy by setting a simple balance between sodium and chloride while letting potassium and sulfate be administered through amino acids. Set sodium to range between 0.14 to 0.18 % and chloride equal to or a maximum of 0.02 % higher.
Some exceptions include producers in coastal regions. The salinity (total dissolved solids; TDS) in these regions is generally higher than normal. For optimal performance the TDS should be less than 1000 ppm. Above 3000 ppm will impact performance. Adjustments can also be made due to the hardness of water, generally driven by calcium and magnesium concentrations.
Feed Digestibility
When formulating feed, make sure the final product has high digestibility. Consider factors including calcium and carbonate that have high buffering capacity. These minerals will reduce the pH in the proventriculus making digestion more difficult. To aid digestibility, the pH of the water can be lowered.
Conclusions
Good water intake will promote digestion and support good performance. Test water samples regularly to ensure birds are receiving high quality water. Likewise, flush water lines often to prevent buildup of bacteria and other organic material in the lines.