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Feeding Patterns Of Growing Pigs At Warm Constant And Cyclic Temperatures, Hongwei Xin, James A. Deshazer
Feeding Patterns Of Growing Pigs At Warm Constant And Cyclic Temperatures, Hongwei Xin, James A. Deshazer
Hongwei Xin
Feeding behavior of ad libitum-fed^ 39-kg, crossbred gilts was investigated under mean ambient temperatures of 30.8° C with 0, 7, and 16.6° C cycles. Average meal size, 160 to 170 g/pig; meal duration, 13.3 to 14.3 min; and ingestion rate, 12.2 g/min-pig did not appear to be influenced by the temperature conditions. However, meal frequency, 9 to 11 per day, tended to be reduced by elevated hours of exposure to high temperatures. Consequently daily feed intake of the pigs was signiflcantly less in the 16.6° C cycle treatment than in the 0 or 7° C cycle treatments (P<0.01). Feed consumed during the lighting period (0600 h to 2100 h) accounted for 75%, 61%, and 37% of daily feed intake for the 0, 7, and 16.6° C cycle treatments, respectively. Pigs under the 0° C cycle had most feeding activities in the afternoon and evening (55% of daily feed intake). In contrast, pigs under the 16.6° C cycle had most feeding events at night and early morning (91 % of daily feed intake).
Responses Of Pre-Fasted Growing Turkeys To Acute Heat Exposure, Hongwei Xin, James A. Deshazer, Mary M. Beck
Responses Of Pre-Fasted Growing Turkeys To Acute Heat Exposure, Hongwei Xin, James A. Deshazer, Mary M. Beck
Hongwei Xin
Nicholas turkeys at the age of 15 to 16 weeks were fasted for 24 hours in a moderate environment and then subjected to acute heat exposures of various dry-bulb and wet-bulb temperatures (T^u, and T^jj). Total feed intake was not influenced by T^^ of 32*' C, 36"* C or 40° C (P > 0.10), although differences existed in dynamic feeding profiles. Total heat production rate (THP) varied quadratically with T^^, and respiratory quotient (RQ) decreased linearly with T^u,. The lower RQ values at the higher T^i^ levels may have resulted from reduced feed assimilation. No differences were detected on feed intake, …