Injection Site Blemishes— Questions and Answers for Beef Producers

This document provides questions and answers for beef producers regarding injection site blemishes on their cattle

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

Effect of Grazing, Mowing, or Herbicide on Leafy Spurge Control

Leafy spurge (euphorbia esula L.) is an herbaceous perennial which is deep rooted and can reproduce by seeds and rhizomes. First introduced into North America in the 1800’s from Europe, it now covers 25 states in the USA and several provinces in Canada. It is a major concern in North Dakota, South Dakota, Wyoming, Montana, and Nebraska. Leafy spurge is considered a noxious weed that is extremely competitive, establishing itself in pastureland and roadsides. Bangsund et al. (1997) estimated that by 2005, uncontrolled leafy spurge acres would reach 18.5 million in the Northern Great Plains. The cost of leafy spurge is estimated to be in the 100’s of millions of dollars due to lost grazing through a reduction of available AUM’s (animal unit months) and treatment costs which may not be economically feasible. This is impart due to the fact that cattle avoid eating leafy spurge because of post-ingestive negative feedbacks from plant toxins (Kronberg et al., 1993) and avoid grazing in areas where leafy spurge canopy cover is high, thus reducing grass production and utilization (Hein and Miller, 1992). Do to the high costs of herbicides and their ineffective control in the long-term (Lym and Messersmith, 1985), biological controls such as sheep and goats as well as the flea beetle have become more popular tools in controlling leafy spurge (Bangsund et al., 2000). In a pasture setting sheep and goats readily graze forbs and do not experience the build up of toxins that cattle do, making small ruminants ideal biological controls for leafy spurge. The object of this trial was to measure the effectiveness of various control methods on leafy spurge

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)

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

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

The Effect of Stage of Growth and Implant Exposure on Performance and Carcass Composition in Steers

Angus and Angus cross Limousin steers (n = 182; initial BW = 681 ± 61.2 lb) were used to evaluate the influence of an estradiol-trenbolone acetate implant (24mg/120mg) on production efficiency and carcass traits when administered at specific stages of growth. Treatments (TRT) were as follows: No Implant, control (NI), Early Implant, d 1, BW = 681 lb (EI); or Delayed Implant, d 57, BW = 845 lb (DI). Comparisons were also made between the NI and implanted treatments (I; EI + DI). Steers were procured at weaning and were backgrounded (47 d) prior to the initiation of the experiment. Initial predicted carcass composition was 14.9% protein, 13.3% fat, 54.6% moisture, and 17.2% bone. Days on feed was constant across TRT. After 56 d, ADG and gain efficiency (G/F) were improved (P \u3c 0.01) by implants, (NI vs. EI; 3.70 vs 4.19 lb and 0.227 vs. 0.257). At d 57 predicted carcass composition was not different among treatments. From 57 to 112 d, DI caused higher ADG than NI or EI (NI 3.64, EI 3.46, and DI 3.92 lb; P \u3c 0.05) and higher G/F (NI 0.155, EI 0.150, and DI 0.173; P \u3c 0.01). Cumulative ADG (3.64 vs 3.81 lb; P \u3c 0.05) and G/F (0.175 vs. 0.186; P \u3c 0.01) were improved by implants for NI vs. I, respectively with no differences between treatments that involved implants. Cumulative DMI was similar for all TRT. Implants increased dressing percent (63.5 vs. 64.1%; P \u3c 0.05), hot carcass weight (752 vs. 778 lb; P \u3c 0.01), and LM area (11.9 vs 12.6 in2; P \u3c 0.010) for NI vs. I, respectively. Ribfat and kidney, pelvic, and heart fat were unaffected by TRT. Treatment had no effect on the whole carcass proportions of fat, protein, or water. Implants advanced maturity scores (NI A51 vs. I A59; P \u3c 0.01). Marbling scores were reduced (P \u3c 0.05) by EI but not by DI (NI Small65, EI Small20, DI Small36). The percent intramuscular fat content of the LM was reduced (P \u3c 0.10) by EI and was unaffected by DI (NI 5.1, EI 4.0, DI 4.8%). Treatment affected (P \u3c 0.10) the proportion of carcasses with marbling scores greater than Modest0 (NI 23.6, EI 7.8, DI 22.6%). The results of this study suggest that growth of intramuscular fat is sensitive to anabolic growth promotants administered during early periods of growth

A Comparison of Lifetime Implant Strategies for Beef Steers

Lifetime implant strategies were developed and applied to steer calves. The design was intended for evaluating strategies rather than specific implants. Strategies involving increasing potency of products used at common stages of production. Initial implants were administered when calves were approximately 2 mo of age. Implants did not increase BW at weaning or after backgrounding (P \u3e 0.10) although they did increase ADG 5% over non-implanted controls during backgrounding (P \u3c 0.05). The influence of implants on ADG was more pronounced during the finishing phase of production. Implants increased (P \u3c 0.05) finishing phase ADG 18%, DMI 7.2%, and feed efficiency 9.4%. Overall post-weaning ADG increased 12% (P \u3c 0.05) due to implants. Performance results changed when evaluating data on a live versus carcass weight basis due to differences in dressing percent. Increasing potency of the implant strategies caused progressive increases (P \u3c 0.05) in carcass weight and ribeye area. Implanted steers produced fatter carcasses than did non-implanted steers (P \u3c 0.05). There were no advances in skeletal or lean maturity attributable to the potency of the implant strategy. The frequency of carcasses grading Average Choice or better declined with implants. Implant strategies had no relevant influence on shear force. Overall, 12% of carcasses had a shear force \u3e 5.0 kg (undesirable)