Journal or Book Title
Transactions of the ASAE
Research Focus Area(s)
Animal Production Systems Engineering
The posthatch energetics of neonatal chicks exposed to a variety of environmental conditions was investigated. Specifically, moisture production (MP), sensible heat production (SHP), total heat production (THP), respiratory quotient (RQ), and body mass loss (BML) of breeder chicks during a 50 h posthatch holding period in shipping containers at the ambient temperatures of 20, 25, 30, and 35°C with the concomitant relative humidity of 40%, 30%, 22%, and 17%, respectively, were determined. The average responses of the chicks under these environmental conditions were respectively, 3.8, 4.0, 4.1, and 4.6 g·(kg·h)–1 MP; 7.8, 6.4, 5.7, and 5.2 W·kg–1 SHP; and 10.3, 9.1, 8.5, and 8.4 W·kg–1 THP. RQ was independent of the temperature (P = 0.59) and averaged 0.75. BML increased with temperature (P < 0.01) and averaged 5.3, 5.7, 5.9, and 6.3 g·chick–1, or 13.5%, 14.4%, 14.9%, and 15.9% of the initial body mass, respectively. Chick mortalities at 20°C and 25°C (1.09% and 0.71%) were higher than those at 30°C and 35°C (0.28% and 0.33%) (P < 0.01). Based on the criteria of least thermoregulatory efforts and mortality, the thermal neutrality for the unfed, group-housed neonatal chicks was between 30°C and 32°C. Moreover, the metabolic rate of the fasting chicks at thermal neutrality, 77 kcal·day–1/kg0.75 of this study agreed well with the literature value of 70 kcal·day–1/kg0.75 for fasting homeotherms. This study provides unique data for the design and operation of ventilation and environmental control systems during transportation of baby chicks.
American Society of Agricultural Engineers
Xin, Hongwei and Harmon, Jay D., "Responses of Group-housed Neonatal Chicks to Posthatch Holding Environment" (1996). Agricultural and Biosystems Engineering Publications. 103.