Effect of a Solar-Powered Fogging System on Heat Stress Mitigation in HF–Deoni Crossbred Dairy Cattle
Gowtham
Department of Farm Machinery and Power Engineering, College of Agricultural Engineering, Raichur-584 104, Karnataka, India.
K. V. Prakash
Department of Farm Machinery and Power Engineering, College of Agricultural Engineering, Raichur-584 104, Karnataka, India.
J. N. Sreedhara *
Department of Animal Science, College of Agricultural Engineering, University of Agricultural Sciences, Raichur-584 104, Karnataka, India.
Sunil Shirwal
Department of Farm Machinery and Power Engineering, College of Agricultural Engineering, Raichur-584 104, Karnataka, India.
Devanand Maski
Department of Farm Machinery and Power Engineering, College of Agricultural Engineering, Raichur-584 104, Karnataka, India.
G. V. Srinivasa Reddy
Department of Irrigation and Drainage Engineering, College of Agricultural Engineering, Raichur- 584 104, Karnataka, India.
H. Mareppa
Department of Farm Machinery and Power Engineering, College of Agricultural Engineering, Raichur-584 104, Karnataka, India.
V. Raghavendra
Department of Farm Machinery and Power Engineering, College of Agricultural Engineering, Raichur-584 104, Karnataka, India.
*Author to whom correspondence should be addressed.
Abstract
Background: During summer, environmental conditions may exceed the threshold for heat dissipation in dairy cows, increasing heat gain and inducing heat stress. Elevated temperature and heat stress increase respiration rate, rectal temperature and the temperature-humidity index, thereby affecting cow health. Evaporative cooling systems, including foggers, utilise latent heat of evaporation to reduce ambient temperature and improve animal-house microclimate.
Objective: This study evaluated the effectiveness of a solar-powered fogging system for mitigating heat stress and improving thermal comfort in HF–Deoni crossbred dairy cattle.
Methods: The solar-powered cooling system was developed and installed at the Main Agricultural Research Station, University of Agricultural Sciences, Raichur district, Karnataka, India. The system consisted of foggers, a timer switch, solar panels, a battery, a water tank, a charge controller and a hosepipe. Solar panels supplied energy for pump operation, and the four-way fogger assembly dispersed water to reduce air temperature. The system was assessed at three levels of fogger number (6, 12 and 18), fogger height (2.25, 2.50 and 2.75 m) and operational interval (2, 4 and 6 min). Air temperature (AT), relative humidity (RH) and respiration rate (RR) were measured and analysed.
Results: AT, RH and RR were significantly influenced by the treatment combinations. The optimum treatment, consisting of 18 foggers at 2.75 m height and a 4 min interval, reduced AT by 9.2 °C, RR by 49% (29 breaths min-1) and increased RH by 47% (to 66%). Under this treatment, RR decreased from 59 to 30 breaths min-1. Coefficients of variation were 1.44%, 8.30% and 2.62% for AT, RH and RR, respectively. ANOVA confirmed significant individual and interaction effects on RR (P < 0.001; R2 = 0.987).
Conclusion: The system improved the dairy-shed microclimate by reducing AT, increasing RH and lowering RR in HF–Deoni crossbred cows.
Keywords: Air temperature, dairy cattle, evaporative cooling, fogger assembly, heat stress, HF–Deoni crossbred cows, operational time interval, relative humidity, respiration rate, solar panel