Progress 10/01/05 to 09/30/08
Outputs
OUTPUTS: Through the use of supplementation, it is possible to produce beef on pasture that will meet commodity market specifications. More time is required to meet these specifications when diets are strictly forage based. With growing consumer interest in grass-fed and -finished beef, some farmers may prefer not to supplement their cattle and sell their beef directly to customers or specialty markets rather than commodity markets. Dual-purpose Normande-influenced steers had daily gains similar to conventional crossbred beef steers when managed in a pasture finishing system. These results were presented at meetings of the Midwest Forage Association and the Wis. Grassworks Conference. A research brief has been publicized by the UW Center for Integrated Agricultural Systems, which is an organization with the mission of linking grazing research with the grazing community. In addition, Dr. Lehmkuhler was the State Beef Cattle Specialist so these results were disseminated through his Extension presentations, phone conversations and email communication. These findings can help beef producers make better informed decisions related to alternative production systems. PARTICIPANTS: Research was conducted by Dr. Jeff Lehmkuhler (Dept of Animal Sciences), Dr. Dan Undersander (Dept of Agronomy), and Mr. Arin Crooks (UW-CALS Agricultural Research Stations). Partner organizations were CSREES-Hatch, UW Center for Integrated Agricultural Systems and UW-Extension. TARGET AUDIENCES: The target audiences for this project were beef cattle graziers, Extension county agents, and Natural Resource Conservation Service staff PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
We investigated the performance of crossbred beef steers and crossbred Normande steers on pasture with and without supplements during 2005 to 2007 at the Lancaster Agricultural Research Station. We compared a diet based exclusively on pasture with three supplementation strategies. A diet of pasture plus alfalfa pellets was one strategy. The other two pasture supplements included soyhulls and dried distillers grains. One of these two treatments included an ionophore (Rumensin). Steers were offered up to 9 lbs of supplement per head daily. Forty-eight steers were grazed each season with 12 steers per treatment. The pastures were predominately a cool-season grass legume mixture. Of the 12 steers assigned to each treatment, half were of Normande influence and the remaining were crossbred Angus and Hereford sired steers. Alfalfa supplement intake varied considerably between animals. A few steers consumed nearly all 9 pounds offered while others ate only a couple of pounds. There was less variability in the intake of both grain co-product supplements. During the grazing season, steers receiving alfalfa pellets consumed approximately two-thirds the weight of supplement as those receiving the grain co-product. Alfalfa pellets increased daily gains by approximately 0.25 lb/d in comparison to the pasture only treatment. Co-product supplementation increased daily gains approximately 0.7 lb/d. The inclusion of an ionophore significantly increased gain in only one of the three years. Use of grain co-products produced heavier carcass weights and higher dressing percentages. Ribeye area was larger for cattle receiving alfalfa and co-product supplements, primarily due to the heavier carcass weights. Animals were harvested directly off pasture in 2005 and 2007. In 2006, we checked the steers with ultrasound as they approached targeted weight and backfat endpoints. Most of the grain co-product steers met the targets and were harvested directly off pasture. The steers on the pasture-only and alfalfa pellet treatments needed additional time to attain the Select grade weight and marbling. Animals not meeting the targets were placed in a confinement barn and offered alfalfa haylage along with the supplements assigned to their group until they were harvested 60 d later. At that point, carcass differences between treatments were minimal. Meat tenderness was not different among treatments. In addition, meat tenderness of these pasture-based steers was similar to that of ten other steers fed under conventional feedlot management practices and receiving the same amount of co-product supplement in 2005. Steers grazing pasture without any supplement produced beef that was of similar marbling as supplemented cattle. Only in 2007 was the average marbling score greater for the supplementation treatments compared with those from steers consuming just grass. A dry growing season in 2005 resulted in the necessity to remove animals from pasture in early October, resulting in a low percentage of cattle achieving the target quality grade. However, in 2006 and 2007 more than 70 percent of the carcasses from the supplementation treatments graded USDA Select, Choice or Prime.
Publications
- Lehmkuhler, J. and D. Undersander. 2008. Does pasture-finished beef make the grade Center for Integrated Agricultural Systems, Research Brief #77.
- Lehmkuhler, J. and T. Cox. 2008. Forage-based beef production in the bio-energy era. Forage Focus. Forage First, Midwest Forage Assoc., pp. 10-11.
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Progress 01/01/07 to 12/31/07
Outputs
OUTPUTS: Preliminary information from this work has been shared with clientele through presentations at meetings. Approximately 100-150 people were in attendance at the 2007 Grassworks Inc. annual conference in Stephen's Point, WI. This session was recorded on audio tape and made available for purchase by Grassworks. A field day was held at the Lancaster Agricultural Research Station in early fall of 2007. A tour of the farm and an update of results were shared with approximately 30 attendees. In December, an update on the project was made available through the Profitable Pastures for Southwest Wisconsin winter discussion series. Lastly, an update has been prepared for the beef research report that is made available online for the public to access.
PARTICIPANTS: Marcelo Ramos- RA worked on the project Arin Crooks- Superintendent at Lancaster and his staff assisted with the project Fernanda Lopes- Intern worked on the project Pedro Afonso- Intern worked on the project Dan Undersander- Assisted with research design input
TARGET AUDIENCES: Beef cattle producers, graziers and others involved in the industry considering alternative production models for producing beef.
Impacts
A general increase in the awareness and knowledge level of beef producers with respect to alternative beef finishing systems has occurred. Our work has been able to dismiss the belief that pasture finishing systems will yield carcasses with bright yellow fat. This works provides producers with background information regarding animal performance and carcass characteristics when beef cattle are managed with a pasture finishing system. Lastly, the utilization of Normande-sired calves has increased producers awareness of the performance and carcass characteristics of this breed.
Publications
- No publications reported this period
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Progress 01/01/06 to 12/31/06
Outputs
The second set of steers has been finished under the pasture finishing system. Unlike the previous year in which steers were selected and harvested at the end of the grazing season, this year one set of steers were harvested directly off of pasture and the remaining were placed in confinement and offered treatment supplements and ad libitum alfalfa haylage until slaughter. This strategy was implemented to more closely harvest cattle at the desired backfat thickness target endpoint. As seen previously, the intake of alfalfa pellets continues to be more variable than the non-starch co-product supplements. Supplements continue to show enhanced animal performance with performance near similar levels as the previous year. Supplementation with the grain co-products resulted in an average increase in daily gains of 38% over the pasture only steers. Live weight gain was observed to be improved for steers receiving an ionophore this year while this response was not observed in
the previous year. Preliminary gain data from this year would again suggest that Normande-sired steers are similar to more conventional beef breeds. The percentage of carcasses that graded USDA Select or better was improved this year with carcasses from supplemented steers ranging from 75% to 92% Select or better while pasture only was 50%. Shear force values from rib steaks wet aged 21 days were less than 4.0 kg with the average being 2.5 kg which is below predicted threshold levels for consumer acceptance. Additionally, shear force values were similar to samples obtained from five Normande-sired and five conventional beef steers that were placed in the feedlot and offered the grain co-product supplement along with a high concentrate ration for approximately 90 days prior to harvest. When data from the steers harvested from the two years were pooled and correlations investigated, it was noted that a moderately high correlation exists for backfat and marbling scores as one would
expect. Additionally, it was found that a moderate correlation exists between dressing percentage and ribeye area supporting previous research with the feedlot finished cattle. This year the plant graders discounted 37% of the carcass for having "dairy characteristics" which is primarily based on the shape of the longissimus muscle area and muscle expression in the round. This resulted in a $10/cwt discount on the rail for these carcasses. It is uncertain if this is a result of inadequate finish, genetics or a combination of the two. Based upon current prices for feedstuffs utilized in this trial which are nearly double from the time when the trial started, the projected supplement cost of gain over the control cattle is near breakeven or less for the grain co-product supplements while the alfalfa pellet treatment results in a much greater cost of gain. Supplementation of pasture finishing cattle in this trial has enhanced the carcass value as well. A more thorough economic analysis
of the finishing regimes being investigated is necessary before recommendations can be made.
Impacts
Alternative beef production systems are being proposed as consumer demand for natural, organic and/or grass-fed beef increases. Additionally, producers wishing to differentiate their product from commodity beef and milk has resulted in an increased interest in breeds with limited production and genetic data. Some grazing herds have begun to utilize Normande genetics. Being a dual purpose breed, the Normande has also been introduced as a component of crossbreeding programs in a few beef herds due to their ability to produce well muscled, trim and well marbled carcasses. These preliminary findings would suggest that the Normande crossbred steers perform as well as conventional genetics in pasture finishing systems. The use of alfalfa pellets as a supplement for grass-based beef systems may result in variable intake compared to low starch grain co-products. Additionally, grain co-product supplementation may allow for an increased number of carcasses obtaining a quality
grade of Select or higher. A small number of animals produced carcasses with yellow fat and does not appear to be a limitation of pasture-based finishing systems. Producers seeking to pasture or grass finish cattle will be able to utilize this information when considering supplementing pastures and when making breeding decisions in the future.
Publications
- No publications reported this period
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Progress 01/01/05 to 12/31/05
Outputs
Twenty-four steers each of Normande and Conventional genetic influence were utilized. Four supplement treatments were investigated. These included no supplement (GRASS), alfalfa pellets (ALF), 67:33 soybean hulls and dried distillers grains combination (DS), and 67:33 soybean hulls and dried distillers grain plus monensin (RDS). Supplements were offered at levels up to 4.0 kg/d. Thirty-six of the steers, 18 of each genetic source, were selected for harvest. Genetic source did not impact live weight at harvest, hot carcass weight, marbling score, or fat color. Normande-influenced steers were found to have higher dressing percentage, ribeye area, and ribeye/unit of weight (live or carcass) when compared to Conventional steers. Backfat thickness was greater for Conventional cattle than Normande steers. The average marbling scores were observed to be similar though backfat thickness was less for Normande steers. Consumption of the DS and RDS was excellent and most cattle
consumed the daily offering of 4 kg. The intake of ALF was more variable and averaged approximately 50% less than the other supplements. Supplementation increased weight at harvest and HCWT regardless of type. Cattle that consumed grain co-product supplements had greater dressing percentage and more backfat than those receiving ALF and GRASS. Ribeye area was greatest for cattle receiving DS and larger than ALF and GRASS. Cattle consuming RDS had ribeye areas similar to ALF while being larger than GRASS. Steers consuming grain co-products had carcasses with a higher fat color score (more yellow) than those not receiving supplement. The average fat color scores for all treatments however were low. The percentage of carcasses that were graded as Select or greater (excluding those that were dark cutters or yellow carcasses) was 12.5%, 12.5%, 40%, and 50% for GRASS, ALF, DS, and RDS, respectively. A simple correlation table was calculated for the carcass traits to examine relationships.
Marbling was found to be moderately correlated with backfat and dressing percentage. This suggests pasture finishing is similar to other systems in which intramuscular fat (marbling) is deposited as animals approach physiological maturity. A negative relationship existed for frame score (hip height) and backfat. For Normande genetics, a negative relationship was observed for the percentage of Normande-influence and frame score. As the percentage increased from 50% to 90% the cattle tended to be smaller framed. Ribeye area was found to be highly correlated to weight (live and carcass) and a moderate relationship was observed for dressing percentage.
Impacts
Alternative beef production systems are being proposed as consumer demand for natural, organic and/or grass-fed beef increases. Additionally, producers wishing to differentiate their product from commodity beef and milk has resulted in an increased interest in breeds with limited production and genetic data. Some grazing herds have begun to utilize Normande genetics. Being a dual purpose breed, the Normande has also been introduced as a component of crossbreeding programs in a few beef herds due to their ability to produce well muscled, trim and well marbled carcasses. These preliminary findings would suggest that the Normande crossbred steers perform as well as conventional genetics in pasture finishing systems. The use of alfalfa pellets as a supplement for grass-based beef systems may result in variable intake compared to low starch grain co-products. Additionally, grain co-product supplementation may allow for an increased number of carcasses obtaining a quality
grade of Select or higher. A small number of animals produced carcasses with yellow fat and does not appear to be a limitation of pasture-based finishing systems. Producers seeking to pasture or grass finish cattle will be able to utilize this information when considering supplementing pastures and when making breeding decisions in the future.
Publications
- J.W. Lehmkuhler, D.J. Undersander, and A. Crooks. 2005. Pasture Finishing: Effect of Normande Influence and Supplementation. University of Wisconsin-Madison Departement of Animal Sciences Beef Cattle Research Report.
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