Recipient Organization
LOUISIANA STATE UNIVERSITY
202 HIMES HALL
BATON ROUGE,LA 70803-0100
Performing Department
Iberia Research Station
Non Technical Summary
In much of the southeastern United States, beef cattle production is a major enterprise. In Louisiana, the cattle industry had a value of $663 million in 2013, up 18% over 2012 (LSU AgCenter, 2014). Cattle and calves rank second only to poultry which is the largest animal industry in the state. Cow-calf producers in the United States typically market calves at weaning; most of these calves are born during the late-winter and or spring and consequently weaned in the fall. In general, producers have small numbers of cows (less than 100) and 90% of the calves weigh below 230 kg at weaning, leaving them with very little marketing opportunities for those calves. Only some producers have enough calves to market in a truck load (21,800 kg). Marketing alliances between small and medium size producers have had some success. For several weather-related reasons (drought, excessive cold/snowfall) in different areas of the country, cattle prices have been at an all-time high in recent years and have made a fresh weaned calf a valuable commodity, although analysts indicate that these times are not going to last and the cattle cycle will go back to "normal" by 2016. Regardless of the actual conditions, large economic benefits exist for beef cow-calf producers to retain ownership after weaning by growing calves to a heavier sale weight prior to finishing. Over the past two decades more cattle producers have been retaining ownership of their calves through the stocker phase, and in some cases, through the finishing phase as well (McKinnon, 2001; Rathwell, 2000). In addition, an increased number of summer row crop farmers are grazing stockers on winter cover crops, which include annual ryegrass (Lolium multiflorum L.) and small grains. Each year, several million calves graze cool-season pastures in the Southeastern United States to add valuable weight as stocker calves. Utilization of cool-season annual forages is one of the primary venues for growing these calves in this region of the country.In Louisiana there is the chance to grow abundant forage resources. Warm season perennial grasses primarily bermudagrass (Cynodon dactylon) and bahiagrass (Paspalum notatum) sometimes associated with dallisgrass (Paspalum dilatatum) are the "core" of perennial forages. Annual (sorghum-sudan hybrids [Sorghum sp.], pearl millet [Pennisetum glaucum]) summer grasses can complement these resources. In winter, cool season annual grasses (rye [Secale cereale], annual ryegrass) or legumes especially Trifolium sp such as ball (T. nigrescens L.), crimson (T. incarnatum), berseem (T. alexandrium), and white (T. repens) clover among others can be successfully planted. Even though these many species can fit into the different ecoregions of the SE, they are the warm season perennial grasses that have been traditionally the forage base for beef cattle systems. Around them and depending on production objectives there are more (or less) intensive systems. The intensive use of greater nutritive value pastures are usually pursued with classes of cattle that demand them such as stockers (steers and heifers) and forage-fed finishing programs. In spring-calving systems having cool season pastures is a major advantage providing nutritive value to the diet of highly demanding cows around parturition and through the first few months of lactation when nutrient demands are at their peak (NRC, 2000). The use of mixed swards (grasses and legumes) is an attractive alternative for producers because: 1) ruminants show preference for a rich (more than one component) diet (Scaglia and Boland, 2014a), and 2) legumes can fix nitrogen from the atmosphere, hence reducing the need for fertilizer.All these pastures, however, do not provide adequate year round supply of feed or an adequate nutritive composition. There are a few alternatives to extend the grazing season and try to reduce hay feeding periods, also called "transition periods" or "gap periods". These periods (usually May-June and October-December) of the year with these limitations are usually complemented with stockpiled or conserved forages, which, depending on the nutrient requirements of the animal, may or may not need to be supplemented. Forage brassica crops such as turnip, swede, rape, and kale can be spring seeded to supplement pastures in August and September or summer seeded to extend the grazing season in November and December. Due to the increase use of cover crops in the Northeast, Midwest and upper Midwest of the US, producers in the SE became familiar with other forage alternatives that can be used for grazing. Forage brassica crops such as turnip, swede, rape, and kale are annual crops that are highly productive and digestible and can be grazed 80 to 150 days after seeding, depending on the species. In addition, crude protein levels are high, varying from 15 to 25 percent in the herbage and 8 to 15 percent in the roots, depending on the level of nitrogen fertilization and weather conditions. Despite these advantages these forages require appropriate management not only for their own productivity but also for the grazing animals. Brassica crops can cause health disorders in grazing animals if not managed properly. The main disorders are bloat, atypical pneumonia, nitrate poisoning, hemolytic anemia (mainly with kale), hypothyroidism, and polioencephalomalacia (Hall and Jung, 2008).All around the US and Louisiana is no exception, there is a trend showing that consumers demand for "organic" or "natural" foods is increasing sharply. In recent years (up to 2012), there was annual growth in sales of 24 and 39% for natural and organic meats, respectively. Grass-fed beef is within these niche markets and its relevance has been noted by the USDA. In September 2013, The U.S. Department of Agriculture's (USDA) Agricultural Marketing Service (AMS) announced a new Market News report that covers grass fed beef (USDA-AMS, 2013). Furthermore, on April 2014 the USDA Grass Fed Program for Small and Very Small (SVS) Producers was presented as a verification tool for SVS producers to certify that animals meet the requirements of the AMS Grass (Forage) Fed Marketing Claim Standard. For this program, USDA is targeting producers that market 49 cattle or less each year (USDA-AMS, 2014). Adding to this trend, consumers are more inclined to support locally produced products, commercialized in farmers markets, favoring localized economies which by end result will strengthen the community's economy. From 1994 to 2013, the national count of farmer markets directory listings (which is voluntary and self-reported) increased from 1,775 to 8,144 with a 3.6% increase from 2012 (7864) to 2013. In Louisiana there are more than 120 farmer markets (LDAF, 2013).The present proposal plans to contribute to an already developing stocker and forage-fed beef industry in Louisiana and to improve the efficiency of utilization of the forage resources available in the Gulf Coast region.
Animal Health Component
80%
Research Effort Categories
Basic
20%
Applied
80%
Developmental
0%
Goals / Objectives
The major goal of the present project is to evaluate the impact offorage and animal management variables on the performance of stockers grazing a tetraploid ryegrass as well as the study of the effect of breed type on sustainable forage-fed beef production for small producers. An advisory committee as well as stakeholders provided input on this project and their support is guaranteed. The objectives are:1. To determine the optimum stocking rate to manage 'Nelson' tetraploid ryegrass.2. To determine the appropriate supplementation rate using different sources of energy on replacement heifers grazing 'Nelson' annual ryegrass.3. To evaluate the effect of different breed types on an intensive forage system and its interaction with different endpoints on carcass characteristics, beef quality and sustainability of small and very small producers.
Project Methods
Objective 1This experiment will be conducted for 3 years. A tetraploid ryegrass ('Nelson') will be no-tilled planted at a rate of 45 kg/ha in early September of each year. Urea will be used at a rate of 60 units of N/ha in November, a month after grazing starts and if environmental condition are appropriate again in mid to late March. Seventy-two crossbred steers (227 kg) will be used. They will be blocked by weight and genotype into 12 groups of 6 animals each (4 treatments and 3 reps). The four treatments that will be evaluated are: a) 2.5 steers/ha; b) 3.5 steer/ha; c) 5 steers/ha; and d) 6.2 steer/ha. The experimental design is a CRD with 3 replicates. Twelve 1.33 ha pastures will be continuously stocked through the grazing period. Grazing days per paddock will be determined and the average of the three paddocks of each treatment will be reported as the effect of treatment. Steers will be weighed on d 0 and every 14 d thereafter. Mineral mix and water will be available at all times. Forage mass will be determined using the double sampling technique as described by Scaglia et al. (2009a,b). Economic analyses will be performed following Scaglia et al. (2009a). Data will be analyzed in Proc Mixed (SAS) with treatment, year and treatment x year interaction. Treatment and period will be the fixed effects and year the random effect. In all cases, paddock will be the experimental unit AND level of significance will be set at α = 0.05.Objective 2Herbicides for control of clover and broad-leaf weeds will be used. A tetraploid ryegrass ('Nelson') will be no-till planted at a rate of 45 kg/ha on early September of each year. Urea will be used at a rate of 60 units of N/ha on November, a month after grazing starts and if environmental condition are appropriate again in mid to late March. Ninety crossbred heifers (215 kg) will be used. They will be blocked by weight and genotype into 15 groups of 6 animals each (5 treatments and 3 reps). The five treatments that will be evaluated are: a) Control, no supplement; b) 0.5% BW soybean hulls; c) 1% BW soybean hulls; d) 0.5% BW ground corn; e) 1% BW ground corn. The experimental design is a CRD with 3 replicates. Fifteen 1.33 ha pastures will be grazed continuously through the grazing period. Heifers will be weighed and BCS estimated on d 0 and every 14 d thereafter. Mineral mix and water will be available at all times. Forage mass will be determined using the double sampling technique as described by Scaglia et al. (2009a,b). Supplement will be adjusted every 15 d once heifers are weighed. Supplement will be fed at 0800 every day. Grazing behavior parameters: grazing, ruminating, resting, standing and walking will be determined by scan sampling (Altmann, 1974) during the day for 2 consecutive days once a month. Economic analyses will be performed following Scaglia et al. (2009a). Data will be analyzed in Proc Mixed (SAS) with treatment, year and treatment x year interaction. Treatment and period will be the fixed effects and year the random effect. In all cases, paddock will be the experimental unit and level of significance will be set at α = 0.05. Grazing behavior data will be analyzed for treatment, period, and their interaction. Year will be considered the random effect; heifer within treatment by year will be the experimental unit, with day analyzed as a repeated measure. In all cases, level of significance was set at α = 0.05 and trends are defined as P> 0.05 but ≤0.10.Objective 3Annually, 72 spring born steers of 4 different breed types (18 heads/breed type) will be used. Breed types under evaluation will be crossbred (Brahman influenced) dam x Continental sire, British, Brangus, and Holstein for a total of 72 steers. These steers will be on a 100% forage diet until the time of harvest. Holstein steers will be raised using colostrum for 2-4 d and milk replacer thereafter. High nutritive value hay (alfalfa) will be gradually provided and fed until 7-9 mo of age, first as only feed and then as a supplement to summer pastures. After weaning approximately at 7-9 months of age, half the steers from each breed type (36 steers, 9 of each breed type) will be transported (those needed) to the HFRS where they will receive ryegrass baleage in the individual feed intake facility. The other half will be transported (those needed) to the IRS. In terms of forage production this period is the so-called "transition gap" when forages commonly used are not yet available for grazing. This gap will be covered at the IRS with 2 forage management strategies: 1) mixed pastures composed by: pearl millet, forage soybean, cowpeas, annual ryegrass, rye, oats, purple turnips, kale, radish, and berseem clover. This same mixed pasture will be conventionally and no-till planted in mid-to-late August. Twenty hectares will be planted and fertilized at planting with 40 units of N. Another application will be needed (if stand is in good condition) by mid-December. Bermudagrass hay will be available to complement the diet if needed; 2) annual ryegrass + cereal rye planted conventionally; this will provide forage mass to cover any possible forage deficit due to the mixture proposed before; if this ryegrass + rye mixture is not needed for grazing it will be used for baleage production. After the "transition period" is finished, annual forages (ryegrass + berseem clover) will be available for grazing (mid-to late-December). All 72 steers will be blocked by previous treatment within breed type to 12 groups of 6 steers each (3 replicates). Sixteen hectares (12 paddocks of 1.34 ha each) of annual ryegrass and berseem clover will be no-till planted as winter forages in early September. At the end of the grazing period (mid-April), 6 steers/breed type (2 steers/replicate) will be harvested (12-14 mo of age). All 48 (12 per breed type) steers remaining will graze summer pastures mainly bermudagrass ('Jiggs') or ryegrass baleage until annual summer pastures are ready to graze. A mixture of pearl millet + alyceclover + cowpeas will be planted on the same 16 ha where ryegrass + berseem clover will be planted. Fertilizer will be applied at a rate of 50 units of N/ha 30 and 70 d after planting. The steers will be kept within each of the groups so 4 steers/group will graze each of these 12 paddocks. At the end of the summer grazing period (September) 6 steers/breed type will be harvested (16-18 mo of age). The remaining 24 steers (6 steers/breed type) will remain at the IRS until the following May (24-26 mo of age), hence they will be fed ryegrass baleage during the transition period and the same winter pasture (annual ryegrass + berseem clover mix) as previously described. All steers will be weighed on a monthly basis. Steers at each harvest time will be randomly selected and harvested at a commercial abattoir by humane procedures under meat inspection supervision. Carcass information will be collected. Steaks will be fabricated, aged for 7, 14, and 21 d and analyzed for fat content, fatty acid profile, lean and fat color, shear force, measurement of sarcomere length, trained and consumer panel evaluations (Smith et al., 2007; Torrico et al., 2014). Records of inputs will be kept in an orderly fashion and an economic evaluation (costs, returns, net returns) will be conducted. Data will be analyzed in a randomized block design (Lentner and Bishop, 1993) with three replicates. Animal performance, carcass, and forage data will be analyzed using Proc GLM (SAS) with the model including treatment (breed type), year, and their interaction. Treatment least squares means will be calculated and means compared using LSD protected by a significant (P < 0.05) F-value. Pearson product moment correlations among carcass variables, color, lipid, shear force, and sensory measures will be calculated using the CORR procedure of SAS.