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The Most Valuable Steer In The Pen-And Why. The Report of the Pennsylvania Steer Test.
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The Most Valuable Steer In The Pen-And Why The Report of the Pennsylvania Steer Test
The Pennsylvania Steer Test was a cooperative effort of the Pennsylvania Department of Agriculture and Penn State University. The test was conducted at the Pennsylvania Livestock Evaluation Center in Centre County. The objectives of the test were: • To determine the factors that influence profitability of cattle fed in Pennsylvania • To determine the value of feeder cattle produced in Pennsylvania
Procedures: • Commercial beef producers to consign 3 calves • 1.standardized health program • 2. known sires 2. Fed the same diet at the PA Livestock Evaluation Center 3. Carcass data collection using ultrasound to determine a constant-fat endpoint 4. Consumer panel and shear tests for tenderness
The Statement of Purpose: Each 1% increase in value of a PA feeder calf through higher demand represents $800,000 to the industry Each $1 increase in the carcass value of cattle fed in Pennsylvania represents $65 million to the industry
Outline of testing procedures: • Steers were preconditioned with vaccinations completed before arrival at LEC • Were fed in a single pen at the LEC • Corn silage, corn, roasted soybeans and minerals were combined for rations that were .60 Mcal/lb NEg • Steers were evaluated with ultrasound to identify cattle that reached .6 in rib fat at harvest. • All steers were harvested by May 1, 2005. • Performance, carcass, and consumer data were collected. Only 18 steers were tested due to some health issues with 30 incoming steers. However, the steers were a mix of body types and breeds so effective comparisons could be made. Consumer Tests: 1. The boneless ribeye from each steer was captured at the processor, and steaks were cut for consumer evaluations and Warner-Bratzler Shear test for tenderness. 2. Cooked steaks were offered to trained panelists for sensory evaluation. 3. Shear tests were made in duplicate and the average shear value is reported.
The Warner-Bratzler shear test is the method of choice for objective evaluations of tenderness. A 1inch core of cooked steak is placed in an Instron machine like the one above, and the pounds of force required to cut through the core is recorded.
Feedlot Performance • Feed intake for an individual in the pen was the proportion of the individual steer’s average weight to the total average weight in the pen times the total feed intake for the pen. This process accounts for maintenance feed intake and steer weight gain while on test. • 2. All steers were weighed at loadout and the carcass weight will reflect shrink as well as dressing percentage. Bedding: $13.33 per steer Corn $2.25/bushel Minerals $.025/ lb. Roasted beans $235/ton Corn silage $32.00/ton Yardage $.25/day Hay $2.00/steer Actual Costs and Prices: Bedding: $13.33 per steer Corn $2.25/bushel Minerals $.025/ lb. Roasted beans $235/ton Corn silage $32.00/ton Yardage $.25/day Hay $2.00/steer Feeder price $90-$120 depending on weight and color Carcass price $1.45, $1.36, $1.18 for Choice, Select, Standard, respectively Bedding: $13.33 per steer Corn $2.25/bushel Minerals $.025/ lb. Roasted beans $235/ton Corn silage $32.00/ton Yardage $.25/day Hay $2.00/steer Bedding: $13.33 per steer Corn $2.25/bushel Minerals $.025/ lb. Roasted beans $235/ton Corn silage $32.00/ton Yardage $.25/day Hay $2.00/steer Rations were composed of corn, corn silage, roasted soybeans, and minerals calculated to be at NEg of .60 Mcal/lb. Corn silage was tested for moisture and nutrient content, and “book” values were used for the other ingredients. Rations were diluted with corn silage in decreasing amounts until desired rations were being eaten. Hay was offered free-choice at entry and was discontinued within 2 weeks after the cattle arrived.
Age Caloric intake Health Carcass Merit Genetics Implants Previous nutrition Carcass merit is determined by a matrix of factors that are both independent and dependent on other factors. For example, cattle that ever suffered from pneumonia will tend to have lower quality grades in spite of all other factors, but genetics for quality grade may be able to negate the effect to some degree.
Bone Muscle Fat Small frame Energy Bone Muscle Fat Large frame Implanted
When does marbling start? • Is it a late developing fat depot? Is marbling simply the last fat that is formed as the fattening and maturity process continues? • Can it be developed separately from rib fat? Is marbling fat the same composition and the same metabolic process as the fat over the outside of the carcass? • Can it be depressed or accelerated? Are there ways to manipulate the accretion of marbling fat in addition to-or in the opposite effect of-outside fat; are there ways to reduce the accretion of marbling fat in spite of continued accretion of outside fat? The use of ultrasonics has allowed researchers to study the accretion of marbling fat in live animals over time, and this has provided some important insights into the biology of marbling in cattle.
Backfat and Marbling Regressed Against Hot Carcass Weight We now know that, given the energetic concentration of a diet that will allow marbling fat deposition, marbling accretion can be linear over time. Secondly, outside fat deposition is more of a maturity effect and is independent of marbling accretion. When the nutritional plane over a long period of time-preweaning through postweaning-is high enough, low choice grade will be reached at a lower carcass weight and at a lower fat thickness. This is the reason calf-feds are known to grade better at a lighter carcass weight and with less outside fat. Bruns et. al.,1999
Backfat and Marbling Regressed Against Hot Carcass Weight The traditional method of buying cattle that are thin, have been backgrounded at a lower energy intake, and are older we now know results in an extended feeding period to reach choice grade. We have insisted on cattle having more outside fat in order to grade because it was necessary for the marbling accretion to “catch up” to outside fat deposition. “Compensatory gain” is simply the outside fat deposition since this type of weight gain is mostly fat. This is a significantly less efficient system that that in the pervious slide. Bruns et. al.,1999
Growth &Nutrition Marbling development is an intrinsic component of growth Subcutaneous fat deposition is not Compensatory growth may be antagonistic to marbling High growth cattle need more fuel
Ranching for Quality Grade • Late gestation cow nutrition • Neonatal calf health • Calving season • Breeding program • Weaning strategy The most overlooked part of carcass value is the management of the cow herd it came from. Pre-and postweaning nutrition, colostrum quality and intake, genetic selection, and weaning methods will contribute to carcass value after feeding.
High vs Low Marbling In a study in which the progeny of sires with either high or low genetic potential for marbling were fed the same way, it was shown growth and feed conversion were not different.
High vs Low Marbling In that same study it was shown that age, fat thickness, and ribeye area were not different. However, average marbling score and the percentage of the cattle grading choice were significantly different. This proves that cattle can be selected to produce more marbling without changing any of the other production and carcass traits.
Summary Values of All Steers Low High Price $1.45 $1.18 Yardage $47.10 $61.84 Feedcost $220.17 $343.78 Interest $13.54 $25.09 ADG 2.45 3.65 Health costs 0 $27.00 Final weight 922 1367 Wt/day of age 2.21 3.71 Incoming wt 468 782
Net Value= $137.42 Net Value = $18.58 Net value = $60.70 What are the reasons one steer makes more money than another?
Which Trait is the Most Important ? • Sale Price/grade • Yardage cost/days on feed • Feedcost • Interest cost • Final daily gain • Health cost • Final weight • Weight/day of age • Incoming weight A statistical procedure was used that compares the variation in net return with all the factors included, then starts eliminating them one at a time until the most important ones are left.
The Most Important Traits Related to Net Value 1. Price/Grade The Choice/Select spread on a live basis in this example was about $6.00/cwt. This implies as the spread widens, grade will have a more significant impact on net value. As it narrows, concentrate on the other important factors. The management of cattle prior to feeding is a significant factor in feedlot profitability. 2. Yardage/Days on Feed This implies as the yardage costs goes up, so do all the other costs such as feed and interest. Final weight was NOT one of the important factors of net value. This implies that ownership and feeding costs are not offset by more pounds to sell. This would be even more important as feed costs go up. 3. Feedcost Corn was priced at $2.25, so even with cheap feed, the cost of feeding was greater than the value of greater weight by feeding them longer. 4. Interest Interest for the cost of cattle was calculated at 6%. Again, this is fairly cheap.
Summary • Price spreads for Choice and Select were good indicators of net value under these prices. • Ownership costs will offset increased sale weight by feeding cattle longer. Does this imply ownership costs will offset higher carcass values by feeding them longer? A comparison was made for choice and choice qualifiers with a $3.00/cwt premium. The most important factors in net value for this analysis were: 1. Final weight 2. Feed cost 3. Interest cost The price difference between choice and middle choice or better needed to be more than $3.00/cwt to be a more important factor in net value.
Consumer Values Cooked Meat Steer No. 1 2 3 4 Overall Liking 5.4 6.7 7.7 6.5 Flavor 5.9 6.1 7.7 6.5 Texture 5.9 6.3 7.7 6.5 Tenderness 3.7 3.5 3.9 3.5 Juiciness 4.8 4.3 4.4 4.5 1 A 9-point hedonic scale was used with 9=like extremely, 8=like very much, 7=like moderately, 6=like slightly, 5=neither like nor dislike, 4=dislike slightly, 3=dislike moderately, 2=dislike very much, 1=extremely dislike. 2 A 7-point “just about right” scale was used with 7=much too tender(juicy), 6=moderately too tender(juicy), 5=slightly too tender(juicy), 4=just about right, 3=slightly too tough(dry), 2=moderately too tough(dry), 1=much too tough(dry).
Summary • All of the steers were acceptable to consumers • The difference in value among steers is defined largely by ownership costs and how the cattle were bred and managed prior to feeding. • Genetics and cost control for feed and interest are the goals for the most profitable cattle feeding enterprise.