ONA REPORT

published in

THE FLORIDA CATTLEMAN AND LIVESTOCK JOURNAL


June 2014

Research Update


For questions or comments regarding this publication contact: The Range Cattle REC, University of Florida, IFAS


The UF/IFAS, Range Cattle Research and Education Center, centrally located in Ona, has enjoyed a long history of service to the Florida Cattlemen.  Since 1941, our research efforts have focused on relevant problems impacting beef production throughout Florida. The Range Cattle Research and Education Center, is unique among the UF IFAS Units as our primary focus is on a single clientele group, which we define as the owners and managers of Florida’s grazinglands.  At our Center, we address important issues spanning a broad scope of overlapping topics relevant to Florida’s grazinglands, such as forage management, fertilization, soil and water, beef cattle management, invasive animal and plant management, wildlife, and economics of beef and forage production.  Each year the Center’s faculty programs publish over 20 peer-reviewed journal articles covering areas of science that impact Florida’s beef cattle and the grazinglands they occupy.

Currently, the Center houses 8 faculty programs with approximately 20 support staff including biological scientists, technicians, program coordinators, and administrative support personnel.  In addition to research and extension projects, the Center’s faculty mentor numerous MS and PhD graduate students and visiting scientist from around the World.  This article provides an introduction and brief overview of each faculty member’s program and a glimpse into the work that program is currently doing to address research priorities of the Florida Cattlemen’s Association.

Maria Silveira
Associate Professor, Soil and Water Science

The Soil and Water Science program is focused on developing and implementing pasture fertilization strategies that optimize forage production while protecting soil and water resources. A number of research and educational efforts are currently being conducted at Ona to address agronomic and environmental aspects related to pasture fertilization. Our group took the lead in developing and implementing the use of tissue testing in combination with soil test to better predict phosphorus (P) fertilization needs in bahiagrass pastures. For over 15 years, UF/IFAS fertilization recommendations for established bahiagrass in Florida did not include soil testing or P fertilization for the region south of I-4. The incorporation of tissue testing into the fertilizer recommendations created an opportunity to identify and correct P deficiency in bahiagrass pastures. Dr. Silveira’s research on bahiagrass P fertilization also indicated that when P was deficient, bahiagrass yields increased in response to P fertilization with no adverse impacts on water quality when pastures were properly fertilized following the UF/IFAS fertilization recommendations. Maria Silveira

Another ongoing project (2009 – to present) was designed to evaluate bahiagrass responses to various commercial nitrogen (N) fertilizer sources. During the past 6 years, our results indicated that when applied at the typical rate of 60 to 80 lb N/A, all commercial N sources (both traditional and enhanced efficiency fertilizers) evaluated in this field trial have been equally effective at providing bahiagrass with N. Our results also indicated that when N fertilizer is properly applied to established bahiagrass pastures, no negative impacts of N fertilization on water quality are expected, regardless of the N source being used.

Our soil fertility efforts are also focused on highly productive warm-season grasses managed for hay production. A significant number of field observations indicate hay field decline in several regions of the State. One of the reasons for this decline is that many mechanically harvested production systems do not supply adequate potassium (K) and P to replace that removed as harvested forage, consequently, soil K (and P to a lesser extent) availability declines which may often result in poor stand persistence and greater incidence of diseases and insect damage. To address issues, a field study was initiated in 2012 to evaluate Jiggs bermudagrass and limpograss responses to K and P fertilization. Results demonstrated that Jiggs bermudagrass and limpograss yields increased as K fertilization rates increased. Data also indicated that considerable stand losses and concomitant weed infestation occurred at the end of the 2-yr study when K fertilizer was not applied.

Another research area that we are currently focusing our research efforts is to evaluate important ecosystem services associated with Florida grazing lands. For instance, considerable effort is currently being place to better understand the impacts of pasture management on soil carbon sequestration and greenhouse gas emissions. Our research results showed that management practices intended to increase forage production such as N fertilization and proper grazing management increase soil carbon sequestration and are also beneficial to soil quality and fertility conditions.

Lastly, pastures represent the major cropping system where biosolids are recycled in Florida, yet limited information is available to support the importance of biosolids recycling programs in forage-based grazing systems. A large-scale demonstration site is currently being established at Ona to evaluate and demonstrate the potential impacts of biosolids application as a nutrient source for grazed bahiagrass pastures in Florida. Class B biosolids will be applied annually and forage and soil responses will be continuously monitored. For more information on this research and education program, please contact Maria Silveira at mlas@ufl.edu.

Brent Sellers
Associate Professor, Weed Science

The current FCA research priorities for weed control have listed long term “holistic” approaches to weeds including broomsedge, smutgrass, Brazilian pepper, and cogongrass.  There are currently three projects underway addressing two of these four species, as well as potential projects that are currently in progress or planning for the other two species.

Project 1:  “Broomsedge management through fertility.”  This project is based on some preliminary data that was collected in 2011.  After sampling several broomsedge infested pastures, we determined that soil pH is not the sole cause for broomsedge invasion in pastures; different broomsedge species respond differently to soil pH.  After sampling two pastures with decreased broomsedge density after biosolids or another organic material were applied, a hypothesis was developed suggesting that either phosphorous or micronutrients may play a role in suppressing broomsedge invasion.  In fact, research looking at the effect of copper and iron in NW Indiana found that one species of broomsedge did not tolerate either of these micronutrients.  This resulted in establishing 3 studies in central and south FL, looking at the effect of soil pH as well as micro- and macro-nutrients on broomsedge in bahiagrass pastures.  Knowing that broomsedge is a short-lived perennial (3-5 yr lifespan), significant results from this study are not expected until 2015.  Additional greenhouse projects are in the planning process to determine the effects of micro- and macro-nutrients on broomsedge growth and development. 

Project 2: “Sequential Velpar applications for long-term smutgrass control.”  This project is built upon previous research conducted by a former Ph.D. student, Neha Rana.  Her small plot research indicated that using reduced rates of Velpar in sequential years resulted in equal control of a single full rate applied only one year (Table 1).  In addition to this research, results from demonstration plot research revealed that burning and mob-grazing smutgrass infested pastures led to a decrease in the number of plants.  This had led to our current hypothesis that integration of burning, followed by mob-grazing and reduced Velpar rates is more beneficial than applying Velpar alone.  This research is currently underway in Okeechobee County.  The key to this research working is that the pasture should not be more than 50% infested with smutgrass and pastures with infestations greater than 60% should likely be renovated.  If renovation is an option, Neha Rana’s research revealed that a reduced rate of Velpar (1 qt/A) the year after replanting bahiagrass has resulted in >90% control 5 years after treatment; which is equivalent to control observed with a single full rate application of Velpar.  For more information on this research and education program, please contact Brent Sellers at sellersb@ufl.edu.

Table 1.  Smutgrass density recorded from 20 x 20 ft plots two and three years after treatment (YAT) with Velpar in July of 2008 and 2009a


Velpar Rate (pt/acre)

Plants/plot
(2 YAT)

Plants/plot
(3 YAT)

Cost/A in
2008
($)

Cost/A in 2009
($)

Total cost/A
($)

2008

2009

0

0

12 a

31 abc

0.00

0.00

0.00

0

2

13 a

35 ab

0.00

20.00

20.00

0

3

  5 b

40 a

0.00

31.00

31.00

2

2

  1 c

22 cd

20.00

20.00

40.00

2

3

  1 c

  7 f

20.00

31.00

51.00

3

0

  3 bc

23 cd

31.00

0.00

31.00

3

2

  1 c

  9 ef

31.00

20.00

51.00

3

3

  5 b

  7 ef

31.00

31.00

62.00

4

0

  2 c

 19 cd

40.00

0.00

40.00

4

2

  5 bc

  6 f

40.00

20.00

60.00

4

3

  1 c

  3 f

40.00

31.00

71.00

aMeans within a year followed by the same letter are not significantly different according to Fisher’s Protected LSD test at P < 0.05. Values represent mean of 6 observations.

Sarah Lancaster
Assistant Extension Scientist, Weed Science

brazilian pepperBrazilian pepper (Schinus terebinthifolia) and coral ardisia (Ardisia crenata) are two woody plant species that are problematic in natural areas as well as pastures and rangelands.  Both of these plants were initially introduced as ornamental plants and have since become established as difficult-to-control weeds.  Currently, research is being conducted to evaluate the efficacy of a new herbicide, aminocyclopyrachlor on these species.  Aminocyclopyrachlor is a growth regulating herbicide similar to aminopyralid (Milestone) and is one of the active ingredients in the herbicides Perspective, Streamline, and Viewpoint that are currently available for the non-crop market.  It is also a component of the pasture herbicides Invora, Perspective R&P, and Rejuvra, all of which are expected to be marketed in the near future. Data collected during the year of application suggest that aminocyclopyrachlor products can control Brazilian pepper similarly to the current standard treatment of glyphosate plus imazapyr.  However, bahiagrass and bermudagrass are generally more tolerant of aminocyclopyrachlor than the standard treatment.  For more information on this research and education program, please contact Sarah Lancaster at slancaster@ufl.edu.

Image: Brazilian pepper in Charlotte County 6 months after application of Viewpoint at the rate of 20 ounces per acre.

Joao Vendramini
Associate Professor, Forage Agronomy

The forage management program is divided into 4 major areas, including, (1) nutrient management, (2) development and evaluation of new forage species and cultivars, (3) supplementation, and (4) management of conserved forages. On the nutrient management area, a bahiagrass fertilization project has been conducted in collaboration with Dr. Maria Silveira, David Genho, and Jason Bagley. The objective of this project is to develop fertilization practices on bahiagrass pastures to optimize forage production, persistence, and economic return. Research plots were established in three locations to test the effects of 1 or 2- 50 lb nitrogen/acre/year, with or without 60 lb potassium/acre/year. In addition, the effects of phosphorus fertilization on forage production and tissue phosphorus concentration in areas with adequate pH and low soil and tissue phosphorus concentration will be evaluated. 

Developing and evaluating new forage species and cultivars in Florida is a crucial part of the forage management program. Evaluation of Jiggs bermudagrass under grazing was conducted at Ona for 2 years and Jiggs had superior nutritive value and production; however, grazing Jiggs below 6-7 inches stubble height for extended periods of time, during the growing season, decreased Jiggs stand and increased common bermudagrass infestation. In collaboration with the Agronomy Department, one hundred and two hybrids of Floralta x Bigalta limpograss plots were developed and after six years of clipping and grazing trials, 2 entries were approved for release in 2014. In general, the 2 selected limpograss entries have greater forage production, persistence, and nutritive value than Floralta. Brachiaria humidicola (humidicola) is a warm-season grass, planted by seed, adapted to poorly drained soil, and tolerant to low fertility soils. The forage management program is testing a new cultivar of humidicola in Ona and comparing production, nutritive value, and persistence with bahiagrass and limpograss. In addition, we are evaluating a new seeded perennial peanut cultivar. The seeded perennial peanut has similar nutritive value to the rhizomatous perennial peanut and has potential to be overseed on bahiagrass and bermudagrass pastures.

The supplementation program evaluated the effects of different sources and rates of supplement on performance of cow-calf pairs and replacement heifers. A study evaluating the effects of supplementing cow-calf pairs grazing stockpiled limpograss and receiving molasses with different sources of added protein was conducted for 2 years. Preliminary results from this trial indicated that the source of protein did not affect cow body condition score, milk production, and calf performance. The use of monensin to increase the efficiency of limited concentrate supplementation for heifers grazing bahiagrass pastures during the summer was evalauted.  Heifers received 1 lb/d of concentrate supplement. There was no effect of adding monensin to the supplement on heifer’s performance and forage intake. In addition, we are trying to develop creep feeding techniques for heifer calves to increase weaning weight and likely decrease age at puberty. Heifer calves were creep fed with 1 lb soybean meal/d to evaluate the effect on performance and feed:gain ratio. Calves supplemented on creep feeding were heavier at weaning and had an efficient 3:1 feed to added gain conversion.

Beef and dairy producers greatly rely on conserved forage for the winter and the use of haylage and silage has increased in the last five years in Florida. Therefore, management practices to improve the nutritive value of conserved forage during the summer have been evaluated at Ona. Current projects include the evaluation of commercial inoculants and additives used to improve fermentation and nutritive value and decrease mold and mycotoxins in haylage and silage.  The application of 40 lb molasses/ton of forage improved fermentation, nutritive value, and intake of Jiggs silage. The benefits of inoculants on warm-season grass silages have not been consistently observed, therefore, further studies will be conducted in 2014. For more information on this research and education program, please contact Joao Vendramini at jv@ufl.edu.

Raoul Boughton
Assistant Professor, Range Science and Wildlife Ecology

Ranchlands are the sinews and muscle of Florida’s landscapes connecting, buffering and protecting wilderness areas, providing homes and passage for a diverse range of wildlife, and preserving a scenic green space for the soul.  Recognition of the importance of ranching landscapes for continuing survival of wildlife has been slow arriving. In recent years there have been considerable shifts towards acknowledging this fact and supporting efforts have increased so ranchers, and especially ranchers with native rangelands, can continue to improve wildlife habitat while successfully ranching.  A quick look at the list of cost share programs, conservation easement initiatives, and conservation partner programs implemented over the last 30 years, by multiple government agencies and private NGO’s, will give you an idea of how important maintaining ranches and wildlife is to the community at large.

Implicit to this acknowledgement and support is that ranchers are stewards and land managers of not just pasture and cattle, but habitat and wildlife. Ranches play an increasing role in maintaining wildlife populations (both game and non-game), biodiversity and protection of Threatened and Endangered species.   This all sounds great but we have to do better if the larger landscape and protection of our cultural heritage and wildlife is to remain, as so much has already perished, and even more has inadvertently been changed because of human activities.  Four “events” have impacted Florida more than any others, the over-drainage of the landscape, the change in fire regimes, human population increases, and the introduction of invasive species. With continued help both financially (through conservation programs and payments for ecosystem services) and through ongoing training and education I believe Florida ranchers will be the world leading stewards of multipurpose lands, allowing continued beef production while sustaining and protecting a diversity of habitats and wildlife.  owl

To help you as land stewards we are developing the “sustainable rangeland ecosystem program”  which conducts directed research and extension into rangeland habitat management techniques, wildlife demography and disease, problem wildlife, cattle health and resource availability on rangelands. The core focus of the program is promoting the conservation, maintenance and improvement of rangelands for diverse ecosystem functions, with special attention to wildlife. A couple of projects that are starting up include;
 

  1. At the RCREC we will implement a long-term study in the 1200 acres of native range to explicitly understand how two highly important management practices will improve ecosystem services: 1) feral swine control and 2) seasonal timing of prescribed fire. Both removal of feral swine and a shift from winter burn to spring burn are expected to facilitate an increase, in cattle production, wildlife populations, and regulation of disease. In Florida, >1 million feral swine reduce forage quantity and quality, and are implicated in the decline of native species; including upland game birds (turkey, quail), turtles, frogs, alligators and deer. Feral swine also harbor parasites and pathogens of concern to livestock, wildlife and humans. Appropriate timing of fire management in rangeland ecosystems is critical to reduce woody encroachment, improve forage quantity and quality, and create habitat diversity for wildlife.
    coyote
  2. Over the last 30 years coyotes have expanded their range into peninsular Florida and more recently the population seems to have increased. Coyotes can be defined as an apex predator (top of the food chain) and play important roles in shaping wildlife populations, both positive and negative. Unfortunately, they are also a species that can interfere with livestock production, and are causing some early calf loss in Florida. This may be in part to the average size of eastern coyotes being 25% larger than western coyotes. In this developing study we want to answer: How often do coyote interact with cattle and cause calf loss? How does coyote behavior change during calving season? What is the occurrence of coyote calf loss across Florida? What has been the coyote population increase?

  3. Feral Swine are common and plentiful across much of the peninsular of Florida and their impacts upon the environment and economy of ranches many. Ongoing projects have been established to quantify the impacts feral swine have on ranchers and rangelands, and to develop the economic costs of feral swine to the ranching community. A few of our questions include: What are the movement patterns and habitat preference of feral swine? What is the consumption of cattle supplemental feed by feral swine? What impact does feral swine rooting have on forage production? What diseases are shared among feral swine, wildlife and livestock?  How often do feral swine depredate ground nesting birds?

I hope to meet as many of you as possible at Florida Cattleman’s meeting.  For more information on this research and education program, please contact Raoul Boughton at rboughton@ufl.edu.

Phillip Lancaster
Assistant Professor, Beef Cattle Nutrition and Management

Winter supplementation is one of the largest costs to cow-calf producers accounting for 40 to 50% of variable costs.  Finding ways to keep cows productive while reducing feed costs can have a significant impact on profitability. One way is to identify cows that are more efficient at converting feed/forage to pounds of weaned calf. Considerable research has evaluated residual feed intake as a trait for use in selection programs to improve feed efficiency of growing cattle.  Residual feed intake is an excellent trait for selecting bulls that will produce efficient steers in the feedlot. However, several studies indicate that residual feed intake in growing cattle does not translate to a significant improvement in feed efficiency of mature beef cows (Table 1). At the Range Cattle Research and Education Center (REC) in Ona, we have begun to evaluate an alternative trait to residual feed intake for use in mature beef cows. This trait is termed Energy Efficiency Index, and unlike residual feed intake, it is based on the energy metabolism of a mature beef cow throughout the production cycle.  Previous evaluation of energy efficiency index in a herd of Santa Gertrudis cows indicates that it is a heritable trait that could be used in selection programs.  Research at the Range Cattle REC will determine the accuracy of energy efficiency index to identify more efficient cows by measuring feed intake, milk yield, digestibility, and metabolic rate in mature beef cows identified as low energy efficiency index (efficient) or high energy efficiency index (inefficient). We also recently submitted a USDA grant proposal to compare residual feed intake and energy efficiency index for selecting more efficient mature beef cows.  These studies will allow us to better evaluate whether energy efficiency index can be used in selection programs to improve feed efficiency of mature beef cows.

Table 1. Relationships of residual feed intake measured in growing and mature cattle

 

Cattle Description

 

Study

Age 1

Age 2

rp1

Nieuwhof et al., 1992

Growing dairy heifer

Non-pregnant, lactating 1st-calf cow fed similar diet

0.07

Arthur et al., 1999

Growing heifer

Non-pregnant, non-lactating cow fed same diet

0.36*

Archer et al., 2002

Growing heifer

Non-pregnant, non-lactating cow fed same diet

0.40*

Herd et al., 2006

Growing heifer

Non-pregnant, non-lactating cow fed same diet

0.39*

Adcock et al., 2011

Growing heifer

Non-pregnant, lactating cow fed same diet

0.30*

Black et al., 2013

Growing heifer

Non-pregnant, lactating cow fed different diet

0.13

Hafla et al., 2013

Growing heifer

Pregnant, non-lactating 1st or 2nd-calf cow fed different diet

0.42*

1rp = phenotypic correlation coefficient.
*Correlation coefficient is different from zero (P < 0.05).

In Florida, cows are rebreeding during winter and early spring when supplemental feed is needed most.  This means critical nutrients for fetal development are needed from supplemental feed sources. Previous research in other parts of the country have focused on nutrient deficiencies in mid and late gestation with regard to fetal development based on the timing of winter feed in their production cycle.  Recent research in dairy cattle indicates that nutrient deficiency during the pre-conception period can impact embryo development; however no data is available on performance of offspring from this study.  Currently, at the Range Cattle REC, we are working on developing a study to evaluate protein deficiency, particularly methionine, in lactating beef cows during the pre-conception period on performance of offspring.  This study will allow us to improve recommendations for winter supplementation programs to optimize fetal development. For more information on this research and education program, please contact Phillip Lancaster at palancaster@ufl.edu.

John Arthington
Professor and Center Director, Beef Cattle Nutrition and Management

Figure 1Mineral nutrition, particularly trace minerals, is the primary focus of this research program.  The mineral nutrition of Florida’s grazing cowherds has been an important management consideration for decades.  In fact, the first published account of copper deficiency in grazing cattle in the United States occurred in Florida.  Although our management systems have certainly evolved to account for mineral deficiencies of our forages, we continue to experience problems with the trace mineral nutrition of our calf crop, particularly selenium.  Beef calves are almost always born with adequate trace mineral status.  This is the result of maternal transfer of trace minerals to the calf during gestation.  After birth, however, calves typically undergo a reduction in trace mineral status.  This occurs due to a general lack of trace minerals in milk and most perennial forages.  Despite having access to mineral-fortified, free-choice supplements by the time of weaning, Florida beef calves are commonly marginal or deficient in copper and selenium (Figure 1). One priority area of our program is aimed at research of methods to improve trace mineral status of calves prior to weaning.  Current studies have revealed a specific consumption aversion of trace mineral-fortified supplements by calves.  This response appears to be related to palatabilfigure 2ity issues related to highly soluble sources of copper and zinc, such sulfate and organic ingredient options. Our studies reveal greater intake acceptability when soluble sources of copper and zinc are replaced with hydroxy sources of copper and zinc, which are highly insoluble at neutral pH (Figure 2).  Data from our current studies imply that limit-fed creep feeds, fortified with hydroxy sources of trace minerals are well-consumed by pre-weaned calves and result in a favorable efficiency of body weight gain, and more importantly, result in optimized trace mineral status of calves at the time of weaning.  Research efforts in this area will continue in coming years.  In attempt to create improved mineral nutrition management programs, these research efforts increasingly involve cooperating producer-owned herds.  For more information on this research and education program, please contact John Arthington at jarth@ufl.edu.
















Chris Prevatt
Regional Specialized Agent, Livestock and Forage Economicspicture 2

This program addresses the animal and forage economics issues facing Florida cattle and forage producers. Florida producers have access to many forage publications on the different varieties of warm season grasses, cool season annuals, and legumes. However, they lack information on the cost of production of these forages. To help address these needs we are developing budgets for forage crops in North and South Florida. These budgets will provide a guide for producers on the cost to establish and graze forages as well as the recommended level of inputs, method of establishment, and the production practices for specific forages. Equipped with the information on the cost of production of Florida forages the next step will be to develop an economic analysis of the production of forages to assess which forages are the lowest cost based on forage quality and quantity. This information will help us better determine estimates of the cost per ton of forage produced as well as cost per pound of crude protein and total digestible nutrients.

Additionally, we will be examining different ways to fill in the voids of forage production. The goal of course will be to increase the number of grazing days. For a few producers with a high level management, diverse forage selection, and favorable weather year-round grazing is attainable. This will likely involve a diverse forage production system with both growing and stockpiled grasses to be utilized in order to attain 365 Days of Grazing. To evaluate this alternative, a Forage Production Calculator will be developed based on a grazing management plan to help producers know if the supply of forage meets the animal demand requirements.

On the animal health side of things we are also looking at the economics of internal and external parasite control. The costs of parasite control compared to the economic benefit needs to be evaluated to help guide livestock producers with making sound economic decisions regarding parasite control. Maximizing the additional pounds we can sell from the control of parasites is economically significant to Florida cattle producers. For more information on this research and education program, please contact Chris Prevatt at prevacg@ufl.edu.




 


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