Sorting Cattle - A Review

The purpose of this report is to review the most current concepts of sorting cattle. The reader should be aware that individual feedlot programs and markets will dictate the involvement and extent of sorting and its usefulness

Impact of Castration Time and Method on Carcass and Palatability Traits in Steers

Angus and Angus x Limousin steers from one ranch were used to evaluate the effect of castration time and method on production and carcass traits. At 2 mo of age, calves were randomly assigned to one of two treatments (TRT); surgical castration at 2 mo age (SC) or castrated at 9 mo age (828 lb) by banding (BAND). Calves assigned to SC received a Synovex-C implant at castration. All calves were weaned at 5 mo of age with no difference in weaning weight. Calves were blocked into heavy and light groups with a 45 Mcal NEG/lb diet fed for 91 d (heavy group) and 119 d (light group). A Magnum implant was administered to SC only, 29 d post weaning to steers. No differences were observed between treatments for BW, DMI, ADG, or F/G during backgrounding. At the time of banding, BW was 828 lb for both treatments, SC and BAND. During the 29 d post-banding period, BAND caused reduced (P \u3c 0.05) ADG by 46% with a 47.8% change in F/G (15.7 vs 8.2) while DMI was unaffected. At the start of the finishing phase (30 d post-banding) a Revalor-S was administered to all steers. From this point until harvest, cumulative performance (117 d) did not differ between treatment for ADG, DMI, or F/G; however, an advantage in body weight was maintained at harvest for SC vs BAND (1297 vs 1272 lb; P \u3c 0.05). Banded bulls tended to have less 12th rib fat and had lower Yield Grade. Quality Grade and Warner Bratzler Shear Force were not affected by treatment. These results indicate that similar performance can be achieved during the suckling and background phases between steers and bulls when an appropriate implant strategy is used on the steer calves. Banding as a method of castration reduced gain 29 d post-banding, resulting in surgically castrated calves at 2 mo of age maintaining a weight advantage throughout the finishing period

Feeding Value of Rolled and Whole Shelled Waxy Corn in Finishing Diets

Waxy corn in rolled or whole shelled form was compared with rolled normal corn in finishing diets for cattle. Steers (n = 144; initial BW = 765 lb) were allocated to 18 pens and fed these three grain types in a 123 d experiment. The waxy corn was a sole source grain that tested \u3e99% pure waxy endosperm. The normal rolled was acquired as needed through a commercial elevator. Diets contained 78% grain as NR) normal rolled; WR) waxy rolled; or WW) waxy whole grain. Diet had no effect on DMI and there were no differences for production variables between NR and WR treatments (P \u3e 0.10). When waxy corn was fed in whole grain form there was a 7% reduction (P \u3c 0.05) in ADG and a 5% increase (P \u3c 0.05) in feed required per pound of gain. The reduced ADG caused by WW corresponded to lower carcass weight. The WR treatment caused an increase in KPH (P \u3c 0.05). No other effects on carcass characteristics were observed. In rolled form waxy and normal corn have comparable feeding value in finishing diets. Rolling waxy corn will increase feed value by approximately 5%

Influence of Calcium Metabolism on Meat Tenderness in Heiferettes

Forty beef-type heiferettes (initial BW=1016 ± 93 lb) were used to evaluate the influence of dietary calcium depletion followed by dietary repletion prior to slaughter on carcass and meat quality traits. Treatments were 1.) control - feed calcium diet for duration of trial (13 hd); 2.) calcium depleted 14 days followed by one feeding of replete diet 20 h prior to slaughter (13 hd); 3.) calcium depleted 14 days followed by two feedings of repleted diet 20 h and 44 h before harvest (14 hd). Heifers were sorted on condition and weight from a larger population of 280 head. Heiferettes were fed 56 d before the initiation of the treatments. Treatments were initiated 16 d prior to slaughter. No differences in ADG or F:G were observed during this time. At harvest, no differences were found for end weight, dressing percent, hot carcass weight, backfat, ribeye area, yield grade or marbling score. Measurements of tenderness were conducted using Warner Bratzler Shear force. No differences were observed with 39% of the carcasses classified as tough (greater than 5.0 lb of shear force)

Bolometric and UV Light Curves of Core-Collapse Supernovae

The Swift UV-Optical Telescope (UVOT) has been observing Core-Collapse Supernovae (CCSNe) of all subtypes in the UV and optical since 2005. We present here 50 CCSNe observed with the Swift UVOT, analyzing their UV properties and behavior. Where we have multiple UV detections in all three UV filters (\lambda c = 1928 - 2600 \AA), we generate early time bolometric light curves, analyze the properties of these light curves, the UV contribution to them, and derive empirical corrections for the UV-flux contribution to optical-IR based bolometric light curves

Effects of Limit Feeding a High Concentrate Diet on Feedlot Performance and Carcass Composition of Lambs

Limit feeding high concentrate diets offers several potential benefits to lamb feeders. Limit feeding is one alternative to ad libitum feeding where intake is restricted to an amount which will permit animals to attain some predetermined daily weight gain. This type of feeding system provides a means to reduce day-to-day variations in feed intake, simplifies bunk management, and allows for greater control over feed inventories (Zinn, 1 986) . Using limit feeding to program a particular rate of gain also allows greater marketing flexibility. Restricting intake has been shown to improve the efficiency at which feed is converted into live weight gain in sheep (Glimp et al. , 1989) and cattle (Plegge, 1986) . Reduced average daily gains have been shown to reduce the fat content of empty body weight gains (Turgeon et al. , 1986) . The objectives of this study were to determine the effect of limit feeding a high concentrate diet to achieve three different rates of gain on feedlot performance and body composition of growing lambs

Evaluating the Agronomic Feasibility of Planting late Season Corn for Feedlot Cattle

Yield, Ib/acre, bushel weight (BD), Ib/bu, relative maturity (RELMAT), chemical composition and in vitro dry matter digestibility (IVDMD) were used to screen corn varieties In = 20) of varying maturities grown under the stress of a shortened growing season. Corn varieties were planted in late June of 1996. Whole shell corn (WSC) and ear corn (EC) were harvested. Bushel weight was quantified on WSC. Yields for WSC, and EC were 1941 + 706 and 2307 ± 997 Ib DM/acre, respectively. Whole shell corn and EC were sorted into yield (YGP) groups. Whole shell corn yields were 2942 ± 248, 2305 ± 138, and 1292 ± 343 Ib DM/acre for YGPI through YGP3, respectively. The EC yields were 3740 ± 207, 2980 ± 208, 1897 ± 235 and 1139 ± 455 Ib DM1 acre for YGP 1 through 4, respectively. For WSC, YGP 1, YGP 2 and YGP 3 produced 2529, 1956 and 1099 Ib TDN/ac, respectively. Ear corn YGP 1, YGP 2, YGP 3 and YGP 4 produced 2980, 2180, 1437 and 780 Ib of TDN/ac, respectively. Increased yield in corn varieties grown under the stress of a shortened growing season was attributed to an increase in starch content. Even so, digestibility and energy content were not related (P \u3e .05) to yield or BD. Relative maturity did not influence (P \u3e .05) chemical composition, digestibility or energy content. Results suggest that while selecting earlier maturing corn for short growing seasons improves yields, it gives no advantage to feed value. Bushel weight, yield or maturity date should not be used as single criteria when predicting feed value of corn grown under the stress of a shortened growing season

Comparative Anatomy of a Presorted Pot-load of Yearling Steers

One load (n = 72; initial BW = 745 ± 54.5) of grass-raised Angus-cross yearling steers was purchased from a sale barn in north central South Dakota. The steers were sorted into load lots by sale barn personnel from a larger group of 1200. Upon arrival, steers were used in the 4-day Feedlot Shortcourse before being weighed and appraised for visual differences. Cattle were divided (randomly) into 8 groups of 9 head each. One steer was randomly selected from each of the eight groups to make a 9th group of steers comprised of each classification. The steers were fed until they reached an average visual ribfat depth of 0.40 in. The data would show that even though cattle came from one owner, variation does exist for feedlot and carcass characteristics. This variation can affect marketing endpoints, and if not managed properly, can cause a decrease in profitability

Effect of Single vs. Pulsing Doses of Estradiol 17-β and Trenbolone Acetate in Finishing Steers Fed a High Concentrate Diet

The effect of implant dosing pattern on anabolic response was evaluated in predominately Angus steers (n=192). Steers, except the control, were implanted with 1 of 3 different implant strategies. Cumulatively all implant treatments received a dose of 24 mg estradiol 17-β (E2) and 120 mg trenbolone acetate (TBA). Dosing patterns were 8 mg E2 and 40 mg TBA given 3 times; 12 mg E2 and 60 mg TBA given 2 times or 24 mg E2 and 120 mg TBA given 1 time. Implanted cattle had heavier body weights, increased average daily gain, and lower feed conversion compared to non-implanted controls. There were no differences among the implant treatments for cumulative 133 d body weight gain or average daily gain. Carcass quality was not affected by implant or implant dosing pattern. Dosing pattern did have an affect on growth patterns