Whole Body 40K Loss as a Predictor of Heat Tolerance in Cattle

Feeding and nutrition management of heat-stressed dairy ruminants

“…Lot of studies demonstrated that heat-stressed cattle were in negative nitrogen balance, as consequence of the reduction in feed intake (Kamal and Johnson 1970;Ronchi et al 1999;Shwartz et al 2009;O'Brian et al 2010). The reduction in the feed intake can be counteracted by the increase of protein content of the diet, which can lead to an excess of nitrogen intake.…”

Climatic physiology of cattle

“…Six-month-old Friesian calves taken from an environment of 18-32 °C (r.h. 50 %) for 3 days and given hay and water ad lib. increased their total body water content by an average of 10-11 and body water turnover rate increased from 3-8 to 6-4 ml/kg h (Kamal & Johnson, 1971).…”

“…Previous work showing a reduced bodyweight in a hot environment has underestimated the retardation in growth, because there is an increase in body water which partly hides the real loss of body solids (Macfarlane et al 1969;Siebert & Macfarlane, 1969;Kamal & Seif, 1969;Kamal & Johnson, 1971). Kamal & Seif (1969) point out that some of the loss of solids may be a reduction in gut contents due to reduced food intake in a hot environment.…”

“…There was no significant change in the digestibility of the dry matter of the diet in this experiment and it was concluded that a portion of the energy for growth was used in combating the effects of heat stress. Recent work has shown that there is a decrease in N retention in a hot environment (Vercoe, 1969;Vercoe & Frisch, 1970;Kamal & Johnson, 1970;Kamal et al 1970;Kamal & Johnson, 1971;Colditz & Kellaway, 1972). If hyperthermic steers are given a controlled food intake, they increase their output of urinary N (urea N and creatinine) indicating catabolism of muscle (Vercoe, 1969).…”

Quantifying Nutrients in Effluent from Uncovered, Intact Mature Bovine Carcass Compost Piles Subjected to Storm Events

“…Total initial pile N, P, and K were estimated utilizing the pile construction and management practices outlined above and the following inputs: 200 kg/m 3 sawdust bulk density (Rynk et al 1992), an average 635 kg bovine carcass weight which was provided to us by the dead animal dealer who supplied carcasses for this study, and carcass nutrient contents of 2.32% N; 0.68% P, and 0.26% K by weight (Ellenberger et al 1950;Kamal and Johnson 1970;Woods et al 2005).…”