Thermal balance of cattle grazing winter range: Model application1

Keren, Elai N.; Olson, Bret E.

doi:10.2527/2006.8451238x

Cited by 20 publications

(6 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At subfreezing temperatures the efficiency at which a biological entity utilizes RAD differs from that under hot conditions, due to body orientation, surface contact, and so on; thus adjustments to temperature for RAD are slightly greater per unit of radiation under the coldest conditions (Keren and Olson, 2006). However, the total adjustment will be much less under cold conditions due to the limited amount of RAD provided (e.g., winter conditions).…”

Section: Resultsmentioning

confidence: 98%

A comprehensive index for assessing environmental stress in animals1

Mader

Johnson

Gaughan

2010

Journal of Animal Science

201

131

View full text Add to dashboard Cite

Numerous models and indices exist that attempt to characterize the effect of environmental factors on the comfort of animals and humans. Heat and cold indices have been utilized to adjust ambient temperature (Ta) for the effects of relative humidity (RH) or wind speed (WS) or both for the purposes of obtaining a "feels-like" or apparent temperature. However, no model has been found that incorporates adjustments for RH, WS, and radiation (RAD) over conditions that encompass hot and cold environmental conditions. The objective of this study was to develop a comprehensive climate index (CCI) that has application under a wide range of environmental conditions and provides an adjustment to Ta for RH, WS, and RAD. Environmental data were compiled from 9 separate summer periods in which heat stress events occurred and from 6 different winter periods to develop and validate the CCI. The RH adjustment is derived from an exponential relationship between Ta and RH with temperature being adjusted up or down from an RH value of 30%. At 45 degrees C, the temperature adjustment for increasing RH from 30 to 100% equals approximately 16 degrees C, whereas at -30 degrees C temperature adjustments due to increasing RH from 30 to 100% equal approximately -3.0 degrees C, with greater RH values contributing to a reduced apparent temperature under cold conditions. The relationship between WS and temperature adjustments was also determined to be exponential with a logarithmic adjustment to define appropriate declines in apparent temperature as WS increases. With this index, slower WS results in the greatest change in apparent temperature per unit of WS regardless of whether hot or cold conditions exist. As WS increases, the change in apparent temperature per unit of WS becomes less. Based on existing windchill and heat indices, the effect of WS on apparent temperature is sufficiently similar to allow one equation to be utilized under hot and cold conditions. The RAD component was separated into direct solar radiation and ground surface radiation. Both of these were found to have a linear relationship with Ta. This index will be useful for further development of biological response functions, which are associated with energy exchange, and improving decision-making processes, which are weather-dependent. In addition, the defined thresholds can serve as management and environmental mitigation guidelines to protect and ensure animal comfort.

show abstract

Section: Resultsmentioning

confidence: 98%

A comprehensive index for assessing environmental stress in animals1

Mader

Johnson

Gaughan

2010

Journal of Animal Science

201

131

View full text Add to dashboard Cite

show abstract

“…The thermal environment is the physical environment that directly affects the heat dissipation process of the animal body and is closely related to the metabolic heat and thermoregulation process (Keren and Olson, 2006). The temperature determines the convective heat transfer temperature difference between the surface of the animal body and environment, affecting the convective heat transfer.…”

Section: Effects Of Environmental Factors On Cold Stress In Dairy Cowsmentioning

confidence: 99%

“…Behavioral changes in dairy cows are a response to external stress and are used to adjust imbalances in the body caused by physiological factors (Vaculiková et al, 2017;Shepley and Vasseur, 2021). When a cow is under prolonged cold stress, the cow will also act accordingly to maintain a constant body temperature (Redbo et al, 2001;Keren and Olson, 2006). Additionally, behavioral characteristics are also an outward indication of the health of the cow (Fournel et al, 2017).…”

Section: Correlation Analysis Of Behavioral Characteristics and Cold ...mentioning

confidence: 99%

“…Temperature, humidity, and wind speed are the main drivers of heat exchange between the environment and animals. However, Webster (1971) and Keren and Olson (2006) used physical models to show that solar radiation is critical for the heat balance of cows in cold environments. Regarding lactation, 16 h of illumination per day (114-207 lx) increased the milk yield by 10 to 15% compared with a natural length photoperiod (39-93 lx) of 9 to 12 h (Peters et al, 1978).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Research and application of a new multilevel fuzzy comprehensive evaluation method for cold stress in dairy cows

Zhang

et al. 2022

Journal of Dairy Science

View full text Add to dashboard Cite

Effective and comprehensive evaluation of cold stress is critical for healthy dairy cow breeding in the winter. Previous studies on dairy cow cold stress have considered thermal environmental factors but not physiological factors or air quality. Therefore, this study aimed to propose a multilevel fuzzy comprehensive evaluation (FCE) method for cold stress in dairy cows based on the analytic hierarchy process (AHP) and a genetic algorithm (GA). First, the AHP was used to construct an evaluation index system for cold stress in dairy cows from 3 dimensions: thermal environment (temperature, relative humidity, wind speed, and illumination), physiological factors (respiratory rate, body surface temperature), and air quality [NH 3 , CO 2 , inhalable particulate matter (PM 10 )]. Second, the consistency test of the judgment matrix was transformed into a nonlinear constrained optimization problem and solved using the GA. Next, based on fuzzy set theory, the comment set and membership function were established to classify the degree of cold stress into 5 levels: none, mild, moderate, high, and extreme. Then, the degree of cold stress in cows was obtained using multilevel fuzzy comprehensive judgment. To investigate the effect of illumination indicators on cold stress in dairy cows, 24 prelactation cows from the south and north sides were selected for a 117-d comprehensive cold stress evaluation. The results showed that the mean mild cold stress durations were 605.3 h (25.22 d) and 725.5 h (30.23 d) and the moderate cold stress durations were 67.2 h (2.8 d) and 96 h (4.0 d) on the south and north sides, respectively. Simultaneously, generalized linear mixed model showed that there were significant correlations between the daily cold stress duration and milk yield, feeding time, lying time, and active steps in the cows on both sides. This method can reasonably indicate cow cold stress conditions and better guide cold protection practices in actual production.

show abstract

“…Most desert shrubland ranches showed flat to gently sloping topography where tall bushes and trees are scarce. Under these conditions, cattle cannot protect themselves against hot and cold weather, which are important factors in animal welfare, behaviour and productivity (Sprinkle & Holloway, 2000; Keren & Olson, 2006). The dominant breeds of cattle in the study sites are Bos taurus.…”

Section: Resultsmentioning

confidence: 99%

Beef cattle welfare evaluation during the dry season in the northern Mexico’s cow-calf system using a visual methodology

2013

View full text Add to dashboard Cite

________________________________________________________________________________ AbstractA cattle welfare index was estimated through 14 visual indicators in the cow-calf system in northern Mexico. The study was carried out at 25 ranches in Chihuahua, Mexico. The indicators were rangeland forage availability; rangeland plant diversity; ease of walking owing to terrain slope; ease of walking owing to presence of rocks; water availability; water distribution; water distance; water appearance; heat protection through vegetation; cold protection through vegetation; cold protection through topography; cold protection through management; cattle docility and cattle body condition. A score of 1 to 4 was given to each indicator, rated as poor, fair, good and excellent, respectively. Ranches under study were classified according to their dominant vegetation type. Noticeable differences were obtained among animal welfare indexes, depending on rangeland type. The lowest index of 2.82 was recorded for the desert shrublands, while indexes above 3.0 were observed for the shortgrass prairie and oak-bunchgrass rangelands. Indicators with high values were water availability and distribution. The lower cattle welfare scores were related to natural factors rather than to management indicators. ________________________________________________________________________________ Keywords:Animal welfare, indicators, rangelands # Corresponding author: saucedo.ruben@inifap.gob.mx IntroductionLivestock producers are facing the need to regulate their processes according to new consumer concerns such as natural resources sustainability and animal welfare. This is true for some emerging production systems such as "organic" and "grass beef", which are based on ecological principles and good cattle health (Lund & Rocklinsberg, 2001;Cachiarelli, 2006; Schnettler et al., 2008;Rinehart, 2011). Beyond market demands, animal welfare concerns should follow deeper reasoning, such as recognizing that animals have the right to live healthily and comfortably. Nevertheless, the beef industry is still lacking on this matter. Modern production processes are designed to maximize productivity and profitability, without considering basic animal health and welfare needs (D'Silva, 2006; Thompson, 2009).Whether motivated by humanitarian incentives or not, animal welfare is an issue that has been studied widely around the world since the last decade. Von Borell & Sorensen (2004) indicated that open spaces without overcrowding are good cattle welfare indicators. Llavallol (2006) pointed out that there is no precise definition of cattle welfare, and it is therefore recommended that animals do not go through stress factors such as hunger, thirst, malnutrition, fear, anxiety, physical and thermal suffering, pain, diseases and injuries. Giraudo & Raviolo (2007) stated that animal welfare is reached with appropriate facilities to carry out sanitary and management tasks, to minimize thermal stress, provide shade and fresh water, and reduce stress during animal loading and...

show abstract

Thermal balance of cattle grazing winter range: Model application1

Cited by 20 publications

References 29 publications

A comprehensive index for assessing environmental stress in animals1

A comprehensive index for assessing environmental stress in animals1

Research and application of a new multilevel fuzzy comprehensive evaluation method for cold stress in dairy cows

Beef cattle welfare evaluation during the dry season in the northern Mexico’s cow-calf system using a visual methodology

Contact Info

Product

Resources

About