Two experiments were conducted to determine the effects of diet on growth of steers weaned at approximately 100 vs 205 d of age. In Exp. 1, a 2 x 2 x 2 factorial experiment was conducted using 78 Angus crossbred cow-calf pairs. The factors examined were age at weaning (early, at 103+/-3 d [EW] vs normal, at 203+/-3 d [NW]), feeding strategy (ad libitum vs postweaning programmed intake), and dietary CP concentration (100 vs 120% of NRC [1984] recommended levels). Early-weaned calves had a greater (P < .001) ADG than NW calves from 103 to 203 d and reached market weight at 385 d vs 418 d for NW calves (P < .001). Likewise, steers offered feed for ad libitum consumption reached market weight at 394 d, compared with 409 d for programmed-intake steers (P < .05). In Exp. 2, 64 Angus crossbred steers were either weaned at 93+/-3 d and fed one of four diets, weaned at 210+/-3 d without access to creep feed, or weaned at 210+/-3 d with access to creep feed for 60 d prior to weaning. Early-weaned calves were heavier (P < .01) than NW calves at 210 d if fed either 100 or 90% concentrate diets, and they had greater (P < .001) backfat thickness at 210 d but no difference (P > .10) in longissimus muscle area compared to EW calves fed a 60% concentrate diet. At slaughter, 80 to 100% of steers on all treatments graded low Choice or higher. Feeding high-concentrate diets to EW beef calves accelerated growth rate and fat deposition early in the feeding period and may be a way to provide young cattle for a high-quality beef market.

In Exp. 1, 72 Targhee lambs (initial BW 22.1+/-.3 kg) were used to determine the effects of energy source (alfalfa pasture vs limit-fed, all-concentrate) and ionophore addition on performance, visceral organ mass, and carcass characteristics. There were no differences (P > . 10) in ADG or gain/ feed due to ionophore supplementation. Lambs that grazed alfalfa had greater (P < .05) liver, omasum, abomasum, small intestine, cecum, and large intestine weights than did lambs fed the concentrate diet. Lambs fed the concentrate diet had greater (P < .01) hot carcass weights, larger (P < .01) loin eye areas, and greater (P < .001) dressing percentages than lambs that grazed alfalfa. In Exp. 2, lambs offered the concentrate diet had greater (P < .001) DM and OM digestibilities than lambs offered alfalfa (89.5 and 91.1 vs 72.4 and 74.2%, respectively). Apparent and true N digestibilities were greater (P < .001) for the concentrate diet than for alfalfa (90.9 and 101.7 vs 77.7 and 91.9%, respectively). Likewise, grams of N retained per day were twice as great (P < .001) with the concentrate diet than with alfalfa (14.9 vs 6.0 g/ d). The greater visceral organ mass and resulting increases in energy and protein requirements in lambs that grazed alfalfa were probably responsible for the lesser hot carcass weight and dressing percentage compared with lambs fed 100% concentrate.

A multistate cooperative study was conducted to study the current issue of tail length in docked lambs and its relationship to incidence of rectal prolapse. A total of 1,227 lambs at six locations were randomly allocated to two or three tail dock treatments: 1) short--tail was removed as close to the body as possible, 2) medium--tail was removed at a location midway between the attachment of the tail to the body and the attachment of the caudal folds to the tail, and 3) long--tail was removed at the attachment of the caudal folds to the tail. Short-docked lambs had a greater (P < 0.05) incidence of rectal prolapse (7.8%) than lambs with a medium (4.0%) or a long (1.8%) dock. Female lambs had a higher (P < 0.05) incidence of rectal prolapse than male lambs. At two stations, lambs were finished either in a feedlot on a high-concentrate diet or on pasture with no grain supplementation. At one station, with a very low incidence of rectal prolapse, there was no difference in incidence between lambs finished in the feedlot or on pasture; however, at the station with a relatively high incidence of rectal prolapse, lambs in the feedlot had a higher (P < 0.05) incidence than lambs on pasture. The half-sib estimate of heritability for the incidence of rectal prolapse was low (0.14). The results of this study strongly implicate short dock length as a cause of rectal prolapse in lambs finished on high-concentrate diets. Furthermore, the results of this study and the only other study known conducted on this issue strongly suggest that docking lambs at the site of the attachment of the caudal folds to the tail will result in a negligible incidence of rectal prolapse.

Wagyu-sired (n = 20) and Angus-sired (n = 19) steers and heifers were used to compare the effects of sire breed on feedlot performance, carcass characteristics, and meat tenderness. Calves were weaned at 138 +/- 5 d of age and individually fed a finishing diet consisting of 65% whole corn, 20% protein/vitamin/mineral supplement, and 15% corn silage on a DM basis. Heifers and steers were slaughtered at 535 and 560 kg of BW, respectively. Carcasses were ribbed between the 12th and 13th (USDA grading system) and the 6th and 7th ribs (Japanese grading system) to measure fat thickness, LM area (LMA), and intramuscular fat (IMF). Two steaks were removed from the 12th rib location and aged for 72 h and 14 d to determine Warner-Bratzler shear force and cooking loss. Sire breed x sex interactions were not significant (P > 0.05). Angus-sired calves had greater (P < 0.05) ADG and DMI than Wagyu. Wagyu-sired calves had improved (P < 0.05) feed efficiency than Angus. Sire breed did not affect (P > 0.20) HCW, 12th-rib fat, or USDA yield grade. Carcasses of Wagyu had greater (P = 0.0001) marbling scores at the 12th rib than those of Angus (770.9 vs. 597.3 +/- 41.01, respectively). Carcasses of Wagyu also had greater (P < 0.02) 12th-rib IMF and 6th-rib IMF than Angus, resulting in a greater proportion of carcasses grading Prime (65.0 vs. 21.1%; P = 0.006). Carcasses from Wagyu tended (P = 0.08) to have greater LMA at the 12th rib, whereas Angus carcasses had greater (P < 0.05) LMA at the 6th rib. Steaks from Angus and Wagyu had similar (P > 0.50) tenderness at aging times of 72 h and 14 d. Cooking loss was greater (P < 0.01) for Angus than Wagyu steaks at 72 h and 14 d. Using Wagyu sires vs. Angus sires on British-based commercial cows combined with early weaning management strategies has the potential to produce a product with greater marbling, but is unlikely to significantly enhance tenderness.