Reducing water usage to cool cows by applying smart technologies

When trying to achieve optimum production, lactating, and dry dairy cows must be provided with relief from heat stress. The most practical and common methods to alleviate the negative effects of heat and humidity on lactating and dry dairy cows consist of 3 main approaches: shade, natural ventilation, and active cooling, with active cooling being the most advantageous. Our objective was to determine if an automated smart system (Agpro, Paris, TX) for controlling soaker output is as effective as the conventional approach to controlling soakers, which relies on a set frequency after a threshold temperature is reached. Nulliparous (n = 12) and multiparous (n = 30) pregnant Holsteins cows were dried off 40 ± 9 d (multiparous only) before expected calving and randomly assigned to one of 3 treatments in the same barn: 5-min interval (30s on, 5 min off) cooling periods with shade, fans, and soakers (CL; n = 14); Agpro smart cooling with shade, fans, and soakers (SS; n = 14); and heat stress with only shade and natural ventilation and no active cooling system (HT; n = 14) during the dry period until parturition. Daily DMI of individual cows, pen water intake, and pen water usage from soakers were measured daily. Blood samples for hematocrit were taken weekly. Respiration rate (in breaths per minute [bpm]) and rectal temperature (RT) were measured 3 times weekly. Calf birth weight and gestation length were recorded upon parturition. No differences were observed for gestation length, calf birth weight, dry period length, or hematocrit among the treatments. However, HT cows had lower overall DMI than SS (8.6 vs. 10.1 ± 0.4 kg/d; <i>P</i> = 0.01) and tended to be lower than CL (8.6 vs. 9.5 ± 0.4 kg/d; <i>P</i> = 0.11). Water usage per cow was lowest in the HT group compared with the CL and SS groups (89.6 vs. 225.3 vs. 80.6 ± 156.5 L/cow per day). Respiration rate (68 vs. 53 vs. 48 ± 1.2 bpm; <i>P</i> < 0.01), RT (38.8°C vs. 38.4°C vs. 38.3°C ± 0.03°C; <i>P</i> < 0.01), and vaginal temperatures (38.9°C vs. 38.6°C vs. 38.7°C ± 0.09°C) were affected by treatment with HT, having the higher values relative to CL and SS, respectively. Compared with conventional cooling, the SS system effectively cooled the animals, decreased the estimated total water usage per cow, and maintained adequate animal welfare.