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Activities of Hereford and Santa Gertrudis Cattle on A Southern New Mexico RangeThe Hereford cows spent more time grazing, less time walking, and traveled less distance than the Santa Gertrudis. When compared to results from other locations, there is no apparent relationship between grazing time and quantity of forage per unit area. There were generally 4 grazing periods: about midnight, from daybreak for the next 3 to 3 1/2 hr, midday, and late afternoon for 3 to 3 1/2 hr.
Influence of Winter Supplemental Feeding of Cottonseed Cake on Activities of Beef CowsFeeding beef cows 1.5 pounds of cottonseed cake on alternate days during winter on shortgrass range caused no apparent increase in feeding time over cattle receiving no supplement. However, cattle fed supplemental feed were easier to handle, ruminated more, and walked less time than cattle with no supplement.
Interval of Observation of Grazing Habits of Range Beef CowsReasonably accurate estimates of activities of longer duration, such as grazing and ruminating, can be obtained by observations at intervals of 15 or even 30 min. Observations at 15 min or longer intervals failed to give reliable estimates of such activities as walking, sleeping, nursing calves, defecation, urination and drinking.
Seasonal variation of locomotion and energy expenditure in goats under range grazing conditionsEnergy cost of various activities can be used in conjunction with direct field observations to estimate energy expended in the daily activities of free-ranging animals. The objective of this study was to estimate the energy expenditure due to locomotion of goats on open range. The study was carried out at the 130-ha "Los Pajares" pilot zone, located in the Filabres mountain-range, Almeria. Average elevation is 865 m above sea level. The area has a Mediterranean climate. The mean annual precipitation is 324 mm. The average daily temperatures range from 8.9 degrees C in January to 23.0 degrees C in August. The landscape is characterized by woody plants and perennial grasses. The experimental flock was grazed on its customary routes for 2 days during 4 seasons. The goats were released to graze during the day and then returned to an enclosed shed. Direct observation was used to simulate the total distance walked, the vertical ascent or descent, and to quantify other grazing activities. The energy expenditure of locomotion was calculated from the horizontal and vertical components of travel and the corresponding costs, which had been previously obtained by calorimetry. Daily travel distances by goats on range fluctuated from 5,763 m in summer to 3,482 m in autumn, with an annual average of 4,295 m, which represents a mean speed of 10.8 m/min. The mean annual vertical ascent or descent was 168 m. Estimated heat production due to locomotion ranged from 56.9 to 34.8 kJ/kg(0.75) per day in summer and autumn respectively. These values account for an increased energy requirement at pasture above maintenance of 14.2 and 8.7%, respectively.