Description and commissioning of a novel swine calorimeter unit to calculate heat production and net energy in group-housed pigs

calorimeter, group housing, net energy, pigs.

Munoz Alfonso, Cristhiam Jhoseph ; Drackley, James K, ; ,Murphy, Michael R ; Stein ; HansH

关键词: calorimeter, group housing, net energy, pigs.;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/107841/MUNOZALFONSO-THESIS-2020.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Values for digestible energy (DE), metabolizable energy (ME) and net energy (NE) are used to develop prediction equations for diet formulation, usually calculated from datafor individually housed pigs. However, pigs in commercial conditions are usually housed in groups and allowed ad-libitum feed intake. It is possible therefore that, energy values in group-housed pigs are different from values obtained in individually housed pigs. The Swine Calorimeter Unit (SCU) at the University of Illinois has been constructed to obtain energy values of diets and feed ingredients in group-housed pigs that are allowed ad-libitum access to feed. The SCU contains 6 calorimeter chambers with a capacity to hold 4 to 10 growing-finishing pigs in each chamber. The SCU allows for calculation of DE, ME, and NE of diets because of total, but separate, collection of feces and urine, and measurements of gas exchange in the chambers. Two experiments were conducted as part of the commissioning of the SCU. The first experiment had the objective of testing the hypothesis that there are no differences in the estimated values for total heat production (THP) and NE among the 6-calorimeter chambers if all environmental and dietary conditions are similar. Results indicated that the NE of the diet had a coefficient of variation (CV) of 4.2 % among chambers. The second experiment tested the hypothesis that a greater protein concentration in the diets may result in a greater THP and, therefore, a lower NE value. Results indicated that there were no differences in the NE values between the 2 diets. The energetic loss associated with deamination of excess AA and, urea synthesis may be less than previously believed. Therefore, more research is needed to demonstrate how dietary protein affects THP and NE values of group-housed pigs.