We used chemical composition and in vitro digestibility data from temperate and tropical forages to develop relationships between indices of lignification and forage indigestible NDF. Neutral detergent fiber indigestibility increased nonlinearly as the lignin concentration of the NDF increased. Differences in estimated indigestible NDF using equations developed for a specific forage class (C3 and C4 grasses and legumes) were small and are probably not biologically significant when compared to those estimated from a common equation. Selected equations were compared with the Cornell Net Carbohydrate and Protein System (CNCPS) for the prediction of ADG. The linear equation (2.4 times NDF lignin content) used by the CNCPS and the Beef NRC had some of the largest errors due to mean bias. A log-log model [4.37 x (lignin/NDF)(.84)] provided the best combination of low total prediction error, low mean bias, and minimal error due to regression bias when permanganate lignin was used. A similar equation based on sulfuric acid lignin [6.17 x (lignin/NDF)(.77)] also met the above criteria. These equations then were evaluated with the CNCPS model against animal growth data from diets ranging in forage quality. Regardless of the equation used for predicting unavailable fiber, the CNCPS underpredicted daily gain, with mean biases ranging from -.10 to -.22 kg/d. Regression bias ranged from .13 to .14 kg/d and the coefficients differed from unity (P = .0001). The new equations gave numerically lower energy allowable ADG by steers compared to the linear equation currently used by the CNCPS model. The estimates were lower due to a higher predicted indigestible NDF, which resulted in a lower estimated forage energy value.

The effects of roughage source and timing of inclusion in high-concentrate diets on feedlot performance were evaluated in each of 2 yr with 144 and 120 long-fed Holstein steers, respectively. Roughage, when included in the diet, was delivered in a built-in-roughage (BIR) pellet supplying 15 and 6% roughage (percentage of DM) or hay crop silage (HCS) supplying 7 and 10% roughage (percentage of DM) for the growing and finishing periods, respectively. The six dietary treatments (two pens each) investigated were continuous whole corn and pelleted supplement (no added roughage; WSC-PEL); BIR with cracked corn either in the growing (BIR-G) or finishing (BIR-F) period with whole corn being fed with pelleted supplement when BIR was not part of the diet; BIR and cracked corn fed continuously (BIR-CONT); and two HCS treatments in which the corn was fed either whole (HCS-WSC) or cracked (HCS-CSC) for the entire feeding period. Replicates were slaughtered 4 and 3 wk apart for yr 1 and 2, respectively. Pooled daily gains (yr 1 and 2) for the entire trial (1.39 to 1.45 kg/d) were not different (P > .05). Daily DM and concentrate intakes were lower (P < .001) and gain efficiency was higher (P < .001) for the WSC-PEL than for the other treatments. Carcass characteristics were similar among treatments except for an improved yield grade (P < .02) for the HCS treatments over the BIR treatments. The WSC-PEL treatment was the most profitable (+/steer) and the BIR-CONT diet was the least profitable. The HCS treatments were the most profitable of the roughage treatments. A newly proposed intake prediction equation for feedlot cattle performed similarly to the 1984 NRC equation with long-fed Holstein steer calves.

‘ANPELON’ (Reg. No. 2640‐TCL‐014‐010313, Mexico; Reg. No. CV‐32, PI 669388) winter triticale (× Triticosecale Wittm.) was selected from the heterogeneous population URSS 3310, sent to Universidad Autónoma Agraria Antonio Narro (UAAAN) by the International Maize and Wheat Improvement Center (CIMMYT), Mexico, and registered and released as a forage cultivar in Mexico by the UAAAN and the National Seed Inspection and Certification Service (SNICS) in 2012. ANPELON was released because of its biomass production, regrowth capacity, awnless spikes, and nutritive value. The primary selection was based on agronomic characteristics and resistance to stem rust (caused by Puccinia graminis Pers. f. sp. tritici Eriks. & Henn) and leaf rust (caused by P. recondita Rob. ex Desm. f. sp. tritici) and subsequently, on forage and nutritional characteristics. The reference cultivar was ‘TCLF‐AN‐31’ winter triticale (Reg. No. CV‐25, PI 620762), released as a forage cultivar by the UAAAN in 1992 (Reg. No. TCL‐07‐080592, Mexico).

‘AN38’ (Reg. No. 2461‐TCL‐015‐010313, Mexico; Reg. No. CV‐33, PI 669387) facultative triticale (× Triticosecale Wittmack) was developed from a cross made by the International Maize and Wheat Improvement Center (CIMMYT), Mexico, and reselected and released as a forage cultivar in Mexico by the Universidad Autónoma Agraria Antonio Narro (UAAAN) and the National Seed Inspection and Certification Service (SNICS) in 2012. AN38 was selected from the progeny of the cross LT1071.82//VICUÑA 4, made in Toluca, Mexico, in 1992. AN38 was released because of its biomass production, earliness, nutritive value, and disease resistance. The selection was based on agronomic, forage, and nutritional characteristics and resistance to stem rust (caused by Puccinia graminis Pers. f. sp. tritici Eriks. & Henn) and leaf rust (caused by P. recondita Rob. ex Desm. f. sp. tritici). ‘TCLF‐AN‐105’ facultative triticale (PI 658496), released as a forage cultivar by the UAAAN in 2004 (Reg. No. TCL‐009‐251104, Mexico) was used as reference cultivar.