Growth and health performance of dairy calves drinking reverse osmosis water compared to municipal water

Abstract Text: Our objective was to determine effects of drinking reverse osmosis water (RO) versus municipal city water (MC) on growth and health performance of calves. Twenty-four Holstein calves (12 females, 12 males; 2 d old, 44.6 ± 6.10 kg BW), housed in individual hutches, were used in a 10-wk randomized complete block design study. Calves were blocked by birthdate and sex. Treatments were RO water (Culligan Water Filtration System, Brookings, SD) versus MC water (Brookings Municipal Utilities, Brookings, SD) which contained 13 and 387 mg/L total dissolved solids, respectively. Milk replacer (28% CP; 18% Fat) was fed twice daily during wk 1 through 5 and then once daily during wk 6. At each feeding, 0.45 kg of dry milk replacer was mixed with 2.8 L of respective water type, according to treatment. Calves were fed water and starter pellets ad libitum throughout the study. All intakes were recorded daily. Daily total respiratory scores (healthy ≤ 3, sick ≥ 5) were calculated from the sum of scores for rectal temperature, cough, ocular, and nasal discharge. Fecal consistency scores (0 = firm, 3 = watery) were also recorded daily. Body weights (BW) and frame growth were measured 2 d every 2 wk and jugular blood samples were collected 1 d every 2 wk at 3 h after morning feeding. Fecal grab samples were collected 5×/d for 3 d during wk 10 for analysis of total tract digestibility (TTD) of nutrients. Results were analyzed using MIXED procedures with repeated measures and Tukey’s test for means comparison in SAS 9.4. Significant differences were declared at P < 0.05 and tendencies were declared at 0.05 ≤ P < 0.10. Total DMI and G:F increased more over time for RO than MC. Water intake was less in RO than MC, indicating more efficient water use by calves. Frame growth, BW, ADG, serum glucose, plasma urea nitrogen (PUN), β-hydroxyl butyrate (βHB), TTD of DM and CP were similar. Fecal scores tended to be less (firmer) in calves on RO, with an interaction by time. Respiratory scores had a tendency to decrease more over time when calves drank RO. Results demonstrated calves drinking RO had similar growth with improved G:F and health scores over time compared to MC.

Keywords: reverse osmosis water, growth performance, dairy calf