Influence of protein level on growth performance, dietary energetics and carcass characteristics of Pelibuey × Katahdin lambs finished with isocaloric diets

• Published in: Small ruminant research 2018-03, Vol.160, p.59-64
• Main Authors: Estrada-Angulo, A., Castro-Pérez, B.I., Urías-Estrada, J.D., Ríos-Rincón, F.G., Arteaga-Wences, Y.J., Barreras, A., López-Soto, M.A., Plascencia, A., Zinn, R.A.
• Format: Article
• Language: English
• Subjects: Carcass; Dietary energy; Finishing; Lambs; Protein level; Visceral mass
• ISSN: 0921-4488; 1879-0941
• DOI: 10.1016/j.smallrumres.2018.01.012

•Dietary protein levels in isocaloric diets were evaluated in finishing lambs.•Overall (84-d) growth-performance increased with increasing protein level.•CP level up to 17% will enhance growth performance at initial phase (28-d).•CP level up to 14% will maintain growth performance at middle phase (28-d).•Thereafter (final 28 days), CP levels beyond of 11% are not necessary. Forty Pelibuey × Katahdin intact male lambs (23.0 ± 1.8 kg initial shrunk weight) were used in an 84-day feeding trial (5 pens per treatment, randomized complete block design) to evaluate crude protein level (110, 140, 170, and 200 g/kg diet DM) in isocaloric diets (2.03 Mcal NEm/kg) on finishing-phase growth performance, dietary energetics and carcass traits. Increases in protein levels were accomplished by increasing levels of canola and meat meal. Tallow was used to equilibrate energy levels among diets. Increasing dietary protein level increased (linear effect, P = 0.01) 84-d average daily gain, dry matter intake (linear effect, P = 0.03), and gain efficiency (linear effect, P