EC97-277 Minerals and Vitamins For Beef Cows

Introduction Mineral supplementation programs range from elaborate, cafeteria-style delivery systems to simple white salt blocks put out periodically by producers. The reason for this diversity: little applicable research available for producers to evaluate mineral supplement programs. There is a need of information regarding mineral composition and availability from various feedstuffs (i.e. pasture grasses, hays, by-products, etc.) and the possible interactions between minerals in the digestive system. Also lacking is a data base to establish accurate estimates of mineral requirements for beef cattle. Assessing the consequence of mineral deficiencies in the cow, calf or stocker animal is difficult because slightly lowered weight gains in calves, reduced milk production and/or decreased reproduction rates may occur without visible signs of deficiency. At the same time, excess mineral consumption may cause reduced cow and/or calf performance without obvious signs of toxicity. Potential problems can occur due to mineral undernutrition in the cow herd; however, producers need sufficient information to establish a least cost method of correcting mineral undernutrition

Carcass Traits and Palatability Attributes of Herdmates Finished as Calves or Yearling Steers

A two-year study compared steers from the same herd finished as calves or yearlings at a fat thickness endpoint of 0.5 in. Yearlings yielded heavier carcasses with larger ribeye areas, lower marbling scores and lower quality grades. Calves produced more tender steaks measured by shear force and a consumer taste panel. The probability of a tough steak (based on shear force) from calf-fed steers was 1.9 and 0.02% for 7 and 21 days of aging, respectively, while the risk for yearlings was 29.2 and 4.0%, respectively. Calf-fed steers produced more tender steaks and, after 21 days of aging, steaks from yearlings were similar

Carcass Traits and Palatability Attributes of Herdmates Finished as Calves or Yearling Steers

A two-year study compared steers from the same herd finished as calves or yearlings at a fat thickness endpoint of 0.5 in. Yearlings yielded heavier carcasses with larger ribeye areas, lower marbling scores and lower quality grades. Calves produced more tender steaks measured by shear force and a consumer taste panel. The probability of a tough steak (based on shear force) from calf-fed steers was 1.9 and 0.02% for 7 and 21 days of aging, respectively, while the risk for yearlings was 29.2 and 4.0%, respectively. Calf-fed steers produced more tender steaks and, after 21 days of aging, steaks from yearlings were similar

Carcass Traits and M. Longissimus Lumborum Palatability Attributes of Calf- and Yearling-Finished Steers

A 2-yr experiment was conducted to compare carcass characteristics and meat palatability attributes of steers (³⁄₄ British, ¹⁄₄ Continental) finished postweaning as calves or yearlings. Calves and yearlings of the same contemporary group were designated to a finishing system at weaning. Calves (n = 73) were finished in the feedlot (191 d) on a high-concentrate diet. Yearlings (n = 84) grazed crop residues after weaning, followed by spring and summer pasture grazing, and concluded with a short finishing period (91 d) in the feedlot. All steers were fed to a constant, fat thickness endpoint of 1 cm. The M. longissimus lumborum steaks from each production system were aged for 7, 14, or 21 d for Warner-Bratzler shear force determination and for 7 or 14 d for in-house sensory panel evaluation. Insoluble, percent soluble, and total collagen were determined. Yearlings produced heavier (P \u3c 0.001) carcasses with larger (P \u3c 0.001) LM areas and lower (P \u3c 0.001) marbling scores and quality grades. Calves possessed greater amounts of total collagen (P \u3c 0.001), with a significantly greater percentage of soluble collagen compared with yearlings (39.72 vs. 24.38%). Calves produced steaks with lower (P \u3c 0.001) shear force values and greater (P \u3c 0.001) sensory ratings for flavor. The USDA Choice steaks from the calves were more (P \u3c 0.001) tender and more (P \u3c 0.050) palatable than Choice steaks from yearlings, and USDA Select steaks from calves were rated more tender (P \u3c 0.001), juicy (P = 0.012), and desirable (P \u3c 0.001) than Select steaks from yearlings. As expected, increasing aging time from 7- to 14- to 21-d produced steaks with lower (P \u3c 0.001) shear force values, regardless of the production system. Risk probabilities showed 1.24% of the steaks from calf finished steers and 21.22% of steaks from yearling-finished steers to be tough. Sensory rating probabilities showed the steaks from the calves were most likely to be desirable for tenderness, whereas steaks from the yearlings were most likely to be undesirable for tenderness, juiciness, flavor, and overall acceptability. Thus, calf-finished steers produce carcasses superior in quality and palatability compared with those from yearling finished steers. However, yearling-finished steers can produce tender beef with extended aging

Use of Expected Progeny Differences for Marbling in Beef: I. Production Traits

Six Angus bulls with HIGH (\u3e.4) and six bulls with LOW (\u3c-.16) expected progeny differences (EPD) for marbling were used to evaluate the impact of marbling on progeny production and carcass traits. Bulls were randomly bred to MARC II (¼ Hereford, ¼ Simmental, ¼ Angus, ¼ Gelbvieh) composite cows in each of 2 yr to calve in the spring. At weaning, steers and heifers were separated and managed in different production systems. Steers (n = 131) were fed a growing diet (1.1 Mcal of NEg/kg) for 48 d followed by adaptation to a 93% concentrate finishing diet. Heifers (n = 125) were fed a growing diet (.79 Mcal of NEg/kg) for 191 d followed by adaptation to the same 93% concentrate diet. Steers and heifers from each treatment were slaughtered at two times spaced about 60 d apart within both years. Marbling EPD class had no effect on fat thickness, USDA yield grade, carcass weight, finishing daily gain, finishing DMI, or finishing efficiency ( P \u3e .18). More ( P \u3c .05) carcasses of calves from sires with HIGH EPD for marbling graded USDA Choice than from LOW EPD sires, 74% vs 47%, respectively. Angus sires can be selected to produce progeny that have increased ability to grade Choice without increasing yield grade or decreasing animal growth or feed efficiency

Case Study: Producer concerns and perceptions regarding the effect of methane on cattle production and the environment: A survey of Nebraska producers

Enteric methane production from cattle and its effect on climate change has been a topic of debate. Multiple studies have explored methods to reduce cattle enteric methane production while simultaneously improving performance. However, most strategies developed have not been widely implemented by cattle producers. Knowledge of producer concerns and perceptions on methane production from cattle and its effect on the environment may be limited. Therefore, the objectives of this survey were to determine what Nebraska producers know about methane production by cattle and how it affects performance and to determine whether different age groups, regions of Nebraska, and production size and type affects producer opinions on enteric methane production and climate change. The survey had a response rate of 22%. Regarding climate change, approximately 39% of producers disagreed, 33% were neutral, and 28% agreed they were concerned. However, producers in central and eastern Nebraska were closer to neutral than producers in western Nebraska (P \u3c 0.05). Younger producers perceived cattle to have a more positive effect on the environment and reported that they were more likely to adopt new management techniques that have been shown to improve animal performance than older producers (P \u3c 0.05). Most producers reported receiving production-related information from veterinarians (47.6%), followed by the “other” category (34.9%), the University of Nebraska (15.6%), and state and federal governments, which were the lowest (1.4 and 0.6%, respectively). In the last 3 yr, approximately 57% of producers attended one or fewer extension meetings, but 37% had not attended any extension meetings

Case Study: Producer concerns and perceptions regarding the effect of methane on cattle production and the environment: A survey of Nebraska producers

Enteric methane production from cattle and its effect on climate change has been a topic of debate. Multiple studies have explored methods to reduce cattle enteric methane production while simultaneously improving performance. However, most strategies developed have not been widely implemented by cattle producers. Knowledge of producer concerns and perceptions on methane production from cattle and its effect on the environment may be limited. Therefore, the objectives of this survey were to determine what Nebraska producers know about methane production by cattle and how it affects performance and to determine whether different age groups, regions of Nebraska, and production size and type affects producer opinions on enteric methane production and climate change. The survey had a response rate of 22%. Regarding climate change, approximately 39% of producers disagreed, 33% were neutral, and 28% agreed they were concerned. However, producers in central and eastern Nebraska were closer to neutral than producers in western Nebraska (P \u3c 0.05). Younger producers perceived cattle to have a more positive effect on the environment and reported that they were more likely to adopt new management techniques that have been shown to improve animal performance than older producers (P \u3c 0.05). Most producers reported receiving production-related information from veterinarians (47.6%), followed by the “other” category (34.9%), the University of Nebraska (15.6%), and state and federal governments, which were the lowest (1.4 and 0.6%, respectively). In the last 3 yr, approximately 57% of producers attended one or fewer extension meetings, but 37% had not attended any extension meetings

Effects of Replacement Rate on Cow Herd Budget

Cattle inventory numbers and cow herd size vary cyclically over time. Historically, cattle cycles have lasted about 10 years. However, the most recent cycle is in its 15th year (1990 to 2004) as a result of an eight-year period of liquidation caused by multi-year drought in many western states. In 2004 and 2005, many cow-calf producers will likely begin to rebuild their cow herd in response to improved profit projections and drought relief. Purchasing bred heifers or young cows will be an option for some producers; others will likely choose to retain additional females from within their own herd. While the economic cost differences to purchasing replacement stock versus retaining females is important to evaluate when making the decision to rebuild herds or replace older stock, it is also necessary to consider the budgetary effects of increasing the replacement rate in a cow herd

Economic Analysis of Keeping a Nonpregnant Cow

Abnormally large numbers of nonpregnant cows in cow-calf herds may be caused by diseases like trichomoniasis or a culmination of environmental factors such as heat stress during breeding and abnormally cold winters and wet spring conditions. Typically, producers sell nonpregnant females and replace them with bred heifers or cows. The five-year cash flow budgets developed in this study suggest that in some circumstances it is economically feasible to keep a nonpregnant cow