PSVIII-4 Live growth performance of Jersey steers using an aggressive implant strategy. (5th December 2019)

• Record Type: Journal Article
• Authors: Kirkpatrick, Tylo J; Pillmore, Sierra L; Cooper, Kimberly; Tennant, Travis; Lawrence, Ty
• Is Part Of: Journal of animal science. Volume 97(2019)Supplement 3
• Page Start: 304
• Page End: 304
• Publication Date: 2019-12-05
• Subjects: growth -- implant -- jersey; Livestock -- Periodicals; Livestock; Electronic journals; Periodicals; 636.005
• DOI: 10.1093/jas/skz258.614
• Languages: English
• ISSNs: 0021-8812

Abstract

Abstract: This experiment was designed to study the effect of days on feed and an aggressive implant strategy on Jersey steer growth performance. Steers (n = 30; start of trial body weight (BW) 183 ± 43 kg) were randomly assigned to one of two treatments; negative control (CON) or implanted with Revalor 200 every 70 d (REV; d 0, d 70, d 140, d 210, d 280, d 350) for a total of 6 implants. Steers were weighed every 35 d and daily feed delivery was recorded daily. Data for dry matter intake (DMI) and gain to feed ratio (G:F) were analyzed via a mixed model; the fixed effects were day and treatment. Live growth BW and average daily gain (ADG) used day as the repeated measure and animal as the subject in a repeated measures analysis. Change in BW increased linearly (P < 0.01); treatments differed in BW from d 280 through d 350 (P < 0.01). Average daily gain decreased (P < 0.01) linearly and differed (P < 0.01) at d 70, d 140, d 280, and d 350, but not (P ≥ 0.10) at d 210 or d 420. Dry matter intake was greater (P < 0.05) for REV steers (7.6 kg/d) than CON (6.8 kg/d). Gain to feed ratio did not differ (P ≥ 0.78) between CON steers (0.13 kg/kg dry matter (DM)) and REV (0.14 kg/kg DM) steers, yet G:F differed (P < 0.01) amongst periods (d 70 = 0.21 kg/kg, d 140 = 0.16 kg/kg, d 210 = 0.15 kg/kg, d 280 = 0.13 kg/kg, d 350 = 0.08 kg/kg, d 420 = 0.08 kg/kg). Aggressively implanting Jersey steers improved growth performance by 9.6%, 13.2%, 11.3%, and 7.7% for BW, ADG, DMI, and G:F, respectively.