Effect of soaking and misting on respiration rate, body surface temperature, and body temperature of heat stressed dairy cattle

Reducing heat stress is a key issue for dairy producers. Use of feedline soaking and supplemental airflow effectively reduces heat stress and increases milk production and profitability. High-pressure misting allows water to evaporate in the air, reduces air temperature, and increases relative humidity. Misting also soaks the skin of cattle, resulting in additional cooling as water evaporates from skin surfaces, similar to the cooling effect of feedline soaking. Impact of soaking frequency (5-, 10-, or 15-minute intervals) was compared to continuous high-pressure misting. Cows cooled with either system had lower respiration rates, body surface temperatures, and internal body temperatures than controls. Soaking cattle every 5 minutes or 5-minute soaking plus high-pressure misting produced similar body temperatures, but lower (P\u3c0.01) than those when soaking occurred every 10 or 15 minutes. Skin surface temperatures from the thurl, shoulder, and rear udder were less when cattle were cooled with high-pressure misting. Cattle cooled with high-pressure misting became soaked, thus the cooling effect is the combination of cooler air and water evaporation from the skin. These results indicate that either frequent soaking (every 5 minutes) or continuous high-pressure misting that soaks the skin could be equally effective in reducing heat stress in dairy cattle.; Dairy Day, 2003, Kansas State University, Manhattan, KS, 2003

Effect of soaking and misting on respiration rate, body surface temperature, and body temperature of heat stressed dairy cattle

Reducing heat stress is a key issue for dairy producers. Use of feedline soaking and supplemental airflow effectively reduces heat stress and increases milk production and profitability. High-pressure misting allows water to evaporate in the air, reduces air temperature, and increases relative humidity. Misting also soaks the skin of cattle, resulting in additional cooling as water evaporates from skin surfaces, similar to the cooling effect of feedline soaking. Impact of soaking frequency (5-, 10-, or 15-minute intervals) was compared to continuous high-pressure misting. Cows cooled with either system had lower respiration rates, body surface temperatures, and internal body temperatures than controls. Soaking cattle every 5 minutes or 5-minute soaking plus high-pressure misting produced similar body temperatures, but lower (P<0.01) than those when soaking occurred every 10 or 15 minutes. Skin surface temperatures from the thurl, shoulder, and rear udder were less when cattle were cooled with high-pressure misting. Cattle cooled with high-pressure misting became soaked, thus the cooling effect is the combination of cooler air and water evaporation from the skin. These results indicate that either frequent soaking (every 5 minutes) or continuous high-pressure misting that soaks the skin could be equally effective in reducing heat stress in dairy cattle

Comparison of three fresh cow feeding programs

We evaluated the impact on performance of top dressing a based total mixed ration (TMR) with long-stem alfalfa hay with or without additional dry-rolled corn to the lactating cow diet during the first 5 days postpartum. The three dietary treatments and numbers of cows assigned to each diet were: 1) total mixed ration (TMR; n = 19); 2) TMR + long-stem alfalfa hay (TMR + A; n= 20); and 3) TMR + long-stemmed alfalfa hay + dry-rolled corn (TMR + A + C; n = 20). Top dressing the lactating TMR with long-stem alfalfa hay with or without dry-rolled corn did not reduce the incidence of metabolic disorders in early lactating cows. Six cows, two on each diet, were treated for displaced abomasums. Cows consuming only the TMR lost slightly more body weight during the first 30 days after calving compared to cows fed the other diets. Milk and energy corrected milk (ECM) yields were similar among diets. Fat, protein, and urea nitrogen content in milk were not different among dietary treatments. Lactose content in milk was greater for cows consuming TMR + A than those consuming TMR or TMR + A + C. Concentrations of glucose and urea nitrogen in plasma were not affected by treatment during the initial 5 days of lactation. Concentrations of glucose and urea nitrogen on days 2 and 3 were less for multiparous cows consuming TMR than for multiparous cows consuming TMR + A. Rumen contractions during the first 5 days of lactation were not different among diets. Top dressing the lactating TMR with long-stem alfalfa hay with or without dry-rolled corn was not beneficial in this study. On a dry matter basis, the lactating TMR contained 22% chopped alfalfa hay, 10% corn silage, 20% wet corn gluten feed, 9% whole fuzzy cottonseed, 7.1% expeller soybean meal, 27.4% ground shelled corn, 1.2% molasses, 1.3% Menhaden fishmeal, and 2.0% mineral-vitamin premix. Cows fed diets containing corn silage as the predominant fiber source may respond differently

A Study on the Feasibility of Using Adaptive Structures in the Attenuation of Vibration Characteristics of Rotary Wings.

This paper investigates the feasibility of employing adaptive material to build both sensors and actuators to attenuate the higher harmonic loads developed at the helicopter rotor blades using the elastic flatwise bending (second for hingeless rotors) and the first elastic torsion modes of a single blade deserve special attention in the vibration control. Theoretical investigations, supported by wind tunnel and flight tests, confirmed that these modes are responsible for the larger amplitude loads at 3/rev in four-blade hingeless rotors. This is a situation for which IBC, based on a collocated actuator-sensor arrangement along the blade, and tailored to act specifically on the bending and the torsion modes, is expected to bring further improvements to the reduction of the overall dynamic response of helicopters. The results indicate that there are already real situations for which the adaptive material has enough power to accomplish the task without saturation of the applied electrical field