Skip to main content
ARS Home » Plains Area » Clay Center, Nebraska » U.S. Meat Animal Research Center » Nutrition, Growth and Physiology » Research » Publications at this Location » Publication #309011
Title: Effects of metabolizable energy intake on tympanic temperature and average daily gain of steers finished in southern Chile during wintertime

Author
item ARIAS, RODRIGO - Catholic University - Brazil
item Brown-Brandl, Tami
item MADER, TERRY - Mader Consulting, Llc

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 4/10/2014
Publication Date: 7/1/2014
Citation: Arias, R.A., Brown-Brandl, T., Mader, T.L. 2014. Effects of metabolizable energy intake on tympanic temperature and average daily gain of steers finished in southern Chile during wintertime [abstract]. Journal of Animal Science Supplement. 92(E-Supplement 2):294. Abstract #585.

Interpretive Summary:

Technical Abstract: A total of 24 Angus x Hereford steers (BW = 479.8 ± 4.48) were used to assess the effect of Metabolizable Energy Intake (MEI) on Average Daily Gain (ADG) and Tympanic Temperature (TT) during the wintertime in southern Chile. The study was conducted at the experimental field of the Catholic University of Temuco, and included a period of 21 days for adaptation to diet and facilities. Steers were randomly allocated in 4 pens (6/pen) equipped with a Calan Feeding System. Steers were sorted by BW, assigned to block (lighter or heavier), and then allocated into one of two treatments: T1 = 1.85x or T2 = 2.72x MEI for maintenance. All steers were fed once per day with the same diet; treatments were applied by controlling DMI. Subsequently, five animals/treatment received a device to collect TT; those were retrieved 10 days later. Climatic data were obtained from a weather station located 5 km southeast from the research site. All data were analyzed under a CRBD arrangement (a = 0.05), with each steer an experimental and observational unit. The steers fed with higher MEI showed higher TT than those fed with lower MEI (P < 0.0001) through all days. In addition, both groups followed the same TT pattern throughout the TT collection period. This could be explained by changes in climatic conditions mainly Precipitations (PP) and Wind Speed (WS). The highest TT, in both treatments, was observed in those days without PP, with low WS. On the other hand, the lowest TT was observed when WS and PP were greater. Thus, in adult animals, it appears that WS has an important role in the thermal balance during the wintertime. Similarly, steers fed with low MEI showed a lower TT when compared with those fed high MEI (P < 0.0001), through every hour of the day, even when both groups had theoretically enough energy to cover maintenance requirements. Following the same trend, observed ADG was greater (P = 0.0004) for those steers fed the higher MEI compared with those fed the lower MEI (0.54 vs. 0.17 ± 0.06 kg/d, respectively). This represents a performance of 3.18 times better for T2; however, MEI was only 1.47 times greater in this treatment. In conclusion, based on the data collected so far it can be said that MEI has a direct effect on the TT and ADG of steers finished during the winter period in an open feedlot. In addition, both variables are directly affected by climatic conditions.