Location: Poultry ResearchTitle: Radiant flux preference of neonatal broiler chicks during brooding
|LINHOSS, JOHN - Auburn University|
|Purswell, Joseph - Jody|
|DAVIS, JEREMIAH - Auburn University|
Submitted to: Journal of the ASABE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/18/2018
Publication Date: 8/29/2018
Citation: Linhoss, J.E., Purswell, J.L., Davis, J.D. 2018. Radiant flux preference of neonatal broiler chicks during brooding. Journal of the ASABE. 61(4): 1417-1423. https://doi.org/10.13031/trans.12775.
Interpretive Summary: Supplemental heat is necessary when placing newly hatched chicks in a commercial broiler house. Commercial broiler houses commonly use radiant heaters to provide a range of temperatures to allow chicks to seek comfortable conditions based upon their preferences. However, there is little information about the range of radiant heat intensity that young chicks prefer. Providing the correct range of conditions requires proper thermostat settings and heater height management. This study was designed to measure the ranges of radiant heat that chicks prefer during the first eight days of life. Heat lamps were used to create different zones of radiant intensity, ranging from 30 to 450 W/m2. Chicks were allowed to move freely between each zone. Chick location was recorded and statistically analyzed to determine the proportion of chicks in each zone and predict the intensity where 80% of the chicks were comfortable. Chicks preferred lower radiant intensity as they aged, decreasing from 409 W/m2 at day of hatch to 304 W/m2 at eight days of age. The minimum level of radiant intensity used by the birds decreased from 115 W/m2 to 31 W/m2 over the same period. Understanding the ranges of thermal comfort as chicks develop the ability to regulate their body temperatures allows for more accurate management of heating systems to improve thermal comfort and optimize fuel use during the brooding period.
Technical Abstract: Radiant heat is the most common method of providing supplemental heat in a broiler house. However, little information exists about chick preference for radiant flux. Identifying the ranges of radiant flux that chicks prefer would allow improved management of the thermal environment. The objectives of this study were to determine the radiant flux ranges preferred by broiler chicks during the first eight days of brooding. Three trials were conducted using straight-run broiler chicks. A total of 88 chicks were randomly allocated into two mixed-gender groups and placed into identical 1 m ' 4 m pens for 8 d. Heat lamps were used to create radiant flux zones of 30, 70, 175, and 450 W m-2 in each pen. Chicks were allowed to move freely between the zones, and feed and water were available in each treatment area. Chick location was recorded with a camera at 5 min intervals. For each image, non-linear regression analysis was applied to the cumulative proportion of chicks in each treatment. The resulting equations were used to calculate the range of radiant flux values for which 80% of the chicks exhibited a preference. Chicks exhibited a preference for decreasing radiant flux with age. The mean maximum preferred radiant flux for all trials decreased from 409.4 W/m2 at 1 d to 304.4 W/m2 at 8 d. The mean minimum preferred radiant flux for all trials decreased from 114.5 W/m2 at 1 d to 31.4 W/m2 at 8 d.