Comparison of Estradiol-Trenbolone Acetate Implant Programs for Yearling Steers of Two Genotypes

Yearling steers (n = 400) were used to evaluate relative payout periods for implants when feeding high grain content diets. Implant treatments included (1) control (nonimplanted), (2) Synovex Plus, (3) revalor-S, and (4) Ralgrorevalor-S. The Synovex Plus (2), revalor-S (3) and Ralgro (4) were administered on day 1. The reimplant with revalor-s (4) was administered after 56 d on feed. Steers were managed in two groups. Initial BW and days fed were 782 Ib, 131 d (Group I), and 661 Ib, 145 d (Group 11). Implants increased production rates and efficiencies, increased carcass size and reduced marbling when compared to nonimplanted controls. Production rates and efficiencies and carcass sizes were similar among steers that received implants. Marbling scores and percentage choice carcasses were affected by implants. In general, the delayed use of an estradiol-trenbolone acetate implant improved marbling over d 1 implanting even though there were 56 fewer days on feed after implanting. The energy density of live weight gain was calculated over the course of the feeding period based upon interim period BW and DM1 determinations. Higher energy content of gain early in the feeding period for treatments 1 and 4 were related to marbling, while the energy content of gain late in feeding period was not. These data showed no differences in the relative effective duration of Synovex Plus and revalor-S implants. The influence of implants on carcass quality grades was affected by factors other than elapsed time from implanting to harvest

Comparison of Estradiol-Trenbolone Acetate Implant Programs for Yearling Steers of Two Genotypes

Yearling steers (n = 400) were used to evaluate relative payout periods for implants when feeding high grain content diets. Implant treatments included (1) control (nonimplanted), (2) Synovex Plus, (3) revalor-s, and (4) Ralgro-revalor-s. The Synovex Plus (2), revalor-s (3) and Ralgro (4) were administered on day 1. The reimplant with revalor-s (4) was admnistered after 56 d on feed. Steers were managed in two groups. Initial BW and days fed were 782 lb, 131 d (Group I), and 661 lb, 145 d (Group II). Implants increased production rates and efficiencies, increased carcass size and reduced marbling when compared to nonimplanted controls. Production rates and efficiencies and carcass sizes were similar among steers that received implants. Marbling scores and percentage choice carcasses were affected by implants. In general, the delayed use of an estradiol-trenbolone acetate implant improved marbling over d 1 implanting even though there were 56 fewer days on feed after implanting. The energy density of live weight gain was calculated over the course of the feeding period based upon interim period BW and DMI determinations. Higher energy content of gain early in the feeding period for treatments 1 and 4 were related to marbling, while the energy content of gain late in feeding period was not. These data showed no differences in the relative effective duration of Synovex Plus and revalor-s implants. The influence of implants on carcass quality grades was affected by factors other than elapsed time from implanting to harvest

What Does the Cattle Buyer Look For in Feeder Cattle?

This subject is steeped with opinion, prejudice and fact in a recipe similar to politics. Some issues are understood, definable and reflected in market prices. We all are aware of body weight, fill, frame, and flesh influences on price and value. Unfortunately, these four factors are inadequate for identifying as much of the profit potential differences between feeder cattle as we would like. As the industry pushes to find sources of profitable cattle, a much broader range of issues is being addressed. The motives and rationales behind these promotions deserve serious scrutiny. We need to distinguish between opinion, prejudice and fact. Ranchers, growers and feedlot operators all need to recognize the factors that improve the total biologic and economic efficiency of producing beef. Then, they need to identify realistic, complimentary management strategies between each segment of beef production. The first step in analyzing the system is to recognize everyone\u27s primary business objective. Ranchers are trying to generate cash from grass and fodder resources. Feedlots are trying to increase the cash value of grains. Custom feedlots are trying to sell a unique service. Stocker-growers are trying to generate cash from forages and/or may be offering services by upgrading quality in feeder cattle. Packers are offering another unique service. Since the primary business objective differs between each segment of the industry, the marginal value of various factors changes. Feed cost/gain has little influence on the value of the packer service. Reproductive efficiency is of no direct concern when feedlots are increasing the value of corn. Even so, we are all highly dependent upon the economic viability of each other and need to respect the needs in each segment of the industry. The purpose here is to outline industry needs that ranchers can influence

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

Composition and Nutritive Value of Corn Co-Products from Dry Milling Ethanol Plants

The South Dakota ethanol industry is rapidly expanding. As a direct result of this expansion it is expected that in excess of 500,000 tons of corn co-products will be available to livestock enterprises annually as a feed source. Processing methods are, in general terms, similar among dry milling ethanol plants. However, newer technology and small deviations of methods can alter the nutritive value of the co-products. Subsequently, diet formulations using general nutritive values may be inaccurate and cause production inefficiencies. The objective of this research project was to characterize the composition and nutritive value of corn co-products produced from several dry milling ethanol plants in the upper Midwest

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)

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

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%

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