Agricultural Science Commons^™

Describing The Sward Structure Of Wheat And Annual Ryegrass Swards Grazed By Lambs In Southern Nsw, Shawn R. Mcgrath, James M. Virgona, Michael A. Friend

IGC Proceedings (1977-2023)

Dual-purpose wheats are now an established part of the feed base on many mixed-farms in southern NSW. However agronomic practices can vary and it is unknown whether row spacing will impact the availability of forage for grazing by sheep. Intake has been shown to be affected by a range of factors including tiller length, pasture height, sward density and pasture mass (Allden and Whittaker 1970; Black and Kenney 1984). This study sought to describe the differences in sward structure of grazed wheat swards at two different row spacings in terms of mean height, row height and bulk density and compare …

Tiller Size/Density Compensation In Temperate Climate Grasses Grown In Monoculture Or Intercropping Systems Under Rotational Grazing, Paulo G. Duchini, Gabriela C. Guzatti, Henrique M. N. Ribeiro-Filho, João G. R. Almeida, André F. Sbrissia

IGC Proceedings (1977-2023)

From the standpoint of tiller population dynamics, it is well known that the size and numbers of tillers in forage grasses are inversely related, where a greater tiller population density (TPD) is associated with smaller tillers and vice versa (Sbrissia et al. 2003; Hernandez-Garay et al. 1999; Matthew et al. 1995). This relationship has traditionally been made with the self-thinning power law described by Yoda et al. (1963), which considers the leaf area index (LAI) of the pasture constant when the slope of the relationship between numbers and size of tillers, on a logarithmic scale, is …

Effect Of Fertilizer Level And Intercropping With Bambara Nut (Vigna Subterranea) On The Growth And Herbage Yield Of Maize, Kelechi A. Ike, Leonard C. Nwaigbo, Chioma P. Obasi, Jimoh A. Olanite, Ogechi M. Chilaka

IGC Proceedings (1977-2023)

The low fertility status of most tropical soils has hindered maize production as maize has a strong exhausting effect on the soil. It has been generally observed that maize fails to produce good grain in plots without adequate nutrients (Adediran and Banjoko 2003). Legumes generally are able to fix nitrogen to the soil which the companion crop could benefit from, but usually the nitrogen fixed occurs in insufficient quantities for marginally nitrogen sensitive crops such as maize and hence the required use of fertilizers. Inorganic fertilizers exert strong influences on plant growth, development and yield (Stefano et al. 2004). …

Italian Ryegrass Establishment By Self-Seeding In Integrated Crop-Livestock Systems: Effects Of Grazing Management, Armindo B. Neto, Jean V. Savian, Olivier J. F. Bonnet, Radael M. T. Schons, Paulo C. Vieira, Marcela Santana, José Augusto Q. Díaz, Paulo C. De F. Carvalho

IGC Proceedings (1977-2023)

Recent reports have indicated that integrated crop-livestock systems (ICLS) can enhance sustained crop and livestock production by efficiently using agricultural system resources (Liu et al. 2012). In the subtropical South American regions, soybean (Glycine max L. Merril) and maize (Zea Mays L.) crops are widely grown after Italian ryegrass (Lolium multiflorum Lam) pastures. In this system, the pasture may be established by self-seeding. Self-seedling reduces pasture production costs and extends the grazing period. The stoking method, and especially the grazing intensity, can greatly affect the quantity of seeds added to the soil by affecting the demography …

Development Of Barley Cultivars For Animal Forage In Korea, Ouk-Kyu Han, Tae-Il Park, Tae-Hwa Song, Dea-Wook Kim, Yu-Yong Lee, Ja-Hwan Ku, Jong-Jin Hwang, Chung-Guk Kim, Young-Up Kwon

IGC Proceedings (1977-2023)

In Korea, the domestic consumption of barley as a cereal crop has been decreasing since the 1980s. It has been considered that crop production in the winter-season rice fields could enhance the global competitiveness of domestic livestock industry by providing better quality fodder to livestock and enhancing field use rate. Therefore, the purpose of barley cultivation for cereal food production has been recently replaced by the production of the barley for forage use. Consequently, the area of barley cultivation for forage is markedly increasing in Korea. While any type of barley can be used as forage for feeding cattle, whole …

Animal Production Over Rice-Pasture Rotation System: Animal Performance, R. Cuadro, S. Luzardo, Fabio Montossi, A. Lavecchia

IGC Proceedings (1977-2023)

Fluctuations in commodity prices, determine the need to find strategies to stabilize production in farming systems. The rice - pastures rotation systems are a good example of this, where animal production takes place in the moments where rice is rotated with pastures (3 years rice and 2 years pastures). In this context, INIA has developed a technology adjusted to the east of the country, with the use of "summer tillage" to intensify livestock production through the incorporation of lambs fattening. These technologies, comercially validated with sheep-rice farming systems, can move the process of cattle backgrounding (males and females), but requires …

Interactive Tree And N Supply Effect On Root Mass Of Two Annual Pasture Grasses, Laíse Da S. Pontes, Raquel S. Barro, Edemar F. De Camargo, Vanderley P. Da Silva, José L. Moletta, Keli C. S. Guera, Anibal De Moraes, Paulo C. De F. Carvalho

IGC Proceedings (1977-2023)

A major aim of integrated crop livestock system (ICLS) with trees is to increase the overall land productivity and/or its sustainability by making best use of the environmental resources (water, light and nutrients) used by plant for growth (Jose et al. 2008). Consequently, research efforts have been done in order to investigate the complex animal-plant-soils interactions operating upon the biological production of these systems, and their environmental impacts. For instance, since roots return to soil as a stock of C in the soil is in general larger than shoot return, interest in describing plant root system has increased due …

Methane Emissions From Ruminants On Integrated Crop-Livestock Systems, Laíse Da S. Pontes, Raquel S. Barro, Edemar F. De Camargo, Vanderley P. Da Silva, Ian M. Cezimbra, Alexandre Berndt, Cimélio Bayer, Paulo C. De F. Carvalho

IGC Proceedings (1977-2023)

Ruminant livestock produce ~80 million tonnes of methane (CH4) annually, accounting for ~33% of global anthropogenic emissions of CH4 (Beauchemin et al. 2008). CH4 is a powerful greenhouse gas, with global warming potential of 25 (Eckard et al. 2010), and represents a significant loss of dietary energy (2 to 12% of gross energy of feeds; Patra 2012) in the ruminant production system. Despite greenhouse gas (GHG) emissions have become an increasingly important topic worldwide, there is still a high variability around the estimated values of these emissions, mainly about emissions attributable to livestock (range from 8 to 51%; …

Integrating Beef And Cotton Production Reduces Irrigation Needs In The Texas Southern High Plains, C. Philip Brown, V. G. Allen, Rick Kellison, P. Green, C. J. Zilverberg, P. Johnson, V. Acosta-Martinez, C. P. West

IGC Proceedings (1977-2023)

The Texas High Plains is a semiarid agricultural region located in the central south plains of the United States. This area exemplifies semiarid regions where water is becoming scarce. Crop production depends heavily on irrigation primarily from the Ogallala aquifer at non-sustainable rates of use. Irrigated monoculture cotton (Gossypium hirsutum L.) is the dominant crop but grazing livestock in this once vast grassland is re-emerging as the aquifer declines. Environmental benefits of integrated crop and livestock systems have been suggested. We compared a cotton monoculture with an integrated cotton-forage-beef stocker steer system over 10 yr to determine effects on …

Integrated Crop Livestock Systems--A Key To Sustainable Intensification In Africa, A. J. Duncan, S. A. Tarawali, P. Thorne, D. Valbuena, Katrien Descheemaeker, Sabine Homann-Keetui

IGC Proceedings (1977-2023)

Mixed crop-livestock systems provide livelihoods for a billion people and produce half the world’s cereal and around a third of its beef and milk. Market orientation and strong and growing demand for food provide powerful incentives for sustainable intensification of both crop and livestock enterprises in smallholders’ mixed systems in Africa. Better exploitation of the mutually reinforcing nature of crop and livestock systems can contribute to a positive, inclusive growth trajectory that is both ecologically and economically sustainable. In mixed systems, livestock intensification is often neglected relative to crops, yet livestock can make a positive contribution to raising productivity of …

Perennial Cereals: A Novel Source Of Feed For Grazing Livestock, Matthew Newell, Richard C. Hayes, Philip Larkin

IGC Proceedings (1977-2023)

Initial deployment of perennial cereal crops will likely be as a dual-purpose crop producing forage for livestock as well as grain. This study evaluated the biomass and grain production of 4 wheat × wheatgrass derivative experimental lines under 4 simulated grazing regimes; nil defoliation (D₀), defoliate once (D₁), defoliate twice (D₂) and defoliate twice followed by a simulated hay cut (D₃), and compared performance to a winter wheat, cv. EGA Wedgetail, and the perennial grass Thinopyrum intermedium. Increasing defoliation intensity significantly (P < 0.001) lengthened the time to flowering for all lines. All experimental lines produced less biomass in the first year than EGA Wedgetail but more than Th. intermedium in the first spring. Grain yield …

Re-Growth Yield And Nutritive Value Of Winter Cereals, Gurhan Keles, Serkan Ates, Behic Coskun, Saban Koc

IGC Proceedings (1977-2023)

Cereal crops can be grazed in early winter or early spring when feed is scarce, or to utilize their high feeding value. In the early spring of 2011, the re-growth yield and nutritive value of barley (Hordeum vulgare L.), rye (Secale cereale L.), wheat (Triticum aestivum), oat (Avena sativa L.), and triticale (x Triticosecale Wittmack) grown in the Central Anatolian Region of Turkey, were evaluated after three successive weekly harvests (Cut 1, Cut 2, Cut 3) during the tillering to stem elongation stages. Plants were cut at a height of 5 cm then allowed …

The Role Of Alfalfa And Forage Resources In Crop-Livestock Systems In A Rain-Fed Region Of North-Western China, Yuying Shen, Zhibiao Nan, Fujiang Hou, Lihua Tian, Huimin Yang

IGC Proceedings (1977-2023)

Western China has been facing the challenges of both environmental sustainability and economic development. Current government policies and interventions support the development of integrated crop-livestock production systems for enhancing food security and environment sustainability. Compared with traditional grain-based faming systems, integrated systems have better resource utilisation, however annual forage supply deficits estimated at 1.37 t DM forage/farm are experienced in the region, especially in late winter and early spring. Accordingly, optimising the use of available forage resources is a priority for regional researchers and extension officers, with research seeking pathways for better fodder conservation and greater and more effective use …

A Strategic Approach To Developing The Role Of Perennial Forages For Crop-Livestock Farmers, Rick Llewellyn, Michael Robertson, Richard C. Hayes, David Ferris, Clinton K. Revell, Katrien Descheemaeker

IGC Proceedings (1977-2023)

A substantial proportion of Australian animal production from grazing comes from regions and farms where cropping is the major enterprise. Developing new and improved grazing systems for mixed farms where crop production is the major driver of farm management decisions presents a unique research and development challenge. In this paper we describe a multi-disciplinary farming-systems research approach (‘EverCrop’) aimed at improving farm profitability, risk management and environmental impacts through the development and integration of new grazing options. It has been used to analyse and target new opportunities for farmers to benefit from perennial species across dry Mediterranean-type and temperate regions …

Do Multi-Paddock Systems Increase Evenness Of Grazing At The Paddock Scale?, Robyn A. Cowley, Ian A. White, Mark H. Hearnden, Leigh Hunt, Steve P. Petty, Lindy Symes

IGC Proceedings (1977-2023)

There is ongoing debate about the benefits of multi-paddock rotationally grazed systems compared to continuous grazing (Briske et al. 2008). One of the purported benefits of high density short duration grazing is more spatially uniform defoliation. A commercial-scale trial in northern Australia (Hunt et al. 2013) compared continuously grazed paddocks to cell grazed and wet season spelled systems in newly developed paddocks. This paper reports the effect of grazing system on defoliation with distance to water through time.

Drivers Of Pasture Growth In Perennial Ryegrass Pastures In Northern New Zealand Dairy Pastures, Natalie R. Mapp, Grant M. Rennie, Warren Mcg. King

IGC Proceedings (1977-2023)

The critical importance of pasture production to New Zealand’s economic performance has been widely recognised. However, a number of critical issues have been identified that limit dairy industry growth, including sub-optimal pasture condition and poor pasture persistence. Dairy farm systems in the Waikato and Bay of Plenty provinces in the upper North Island of New Zealand are predominantly pasture-based, with a temperate climate and they represent around 30% of New Zealand’s total number of dairy farms (LIC and DairyNZ, 2012). This project was established to quantify pasture performance and identify factors that drive that performance. We established a network of …

Extending The Period Of High Feed Value In Italian Ryegrass (Lolium Multiflorum Lam.) For Grazing In The Warm Temperate Zone Of Japan, Makoto Kaneko, Yoshi-Nori Nakamura, Akihisa Yamada

IGC Proceedings (1977-2023)

Japan has widely diverse climate conditions, from subtropical in the south to boreal in the north. In warm regions of the temperate zone in the south-west, such as low-lying areas of Kyushu Island, temperate grasses only barely survive during the summer (Area V in Fig. 1). Therefore, for year-round grazing, tropical grasses and temperate grasses have been used, respectively, for summer and winter (Fig. 2). Throughout Japan, grazing is limited for cows and their calves and fattening takes place in barns. Recently, as consumer preference for meat has diversified, the demand for lean meat with less fat from grazing cattle …

Early Sowing And Irrigating Of Rape Crops In Cool Temperate Environments Boosts Forage Yield Potential, Matthew T. Harrison, Keith G. Pembleton, Richard P. Rawnsley

IGC Proceedings (1977-2023)

Forage rape is commonly grown on Tasmanian dairy farms to provide feed during periods of low pasture growth and/or low nutritive value. In these regions, forage crops are generally sown between early spring and late autumn and are commonly rainfed, though farmers may apply a single irrigation at sowing. While the effect of water availability on forage yield has been well characterised for regions in north-western Tasmania (Neilsen 2005), there is a dearth of information for other regions in Tasmania. Hence, the objectives of this study were to identify optimal sowing times for, and determine the extent to which a …

Aboveground Biomass And Soil Moisture As Affected By Short-Term Grazing Exclusion In Eastern Alpine Meadows Of The Qinghai-Tibet Plateau, China, Haibo Liu, Jianping Wu, Wen Wang, Xiaoli Jin, Zhenheng Liu, Wenhua Du

IGC Proceedings (1977-2023)

Heavy grazing substantially influences grassland vegetation and animal nutrition on the Qinghai-Tibet plateau (Guo et al. 2003). Degradation is characterized by a reduction in vegetation height, reduced ground cover decrease in species diversity (Wang et al. 2007).

The objective of this study was to determine the effects of short-term exclusion from grazing on aboveground herbage, forage nutritive value, and soil moisture in an alpine meadow in the eastern zone of the plateau. Three farms, applying different intensity of grazing over the summer months, were compared.

Performance Of Anatolian Merino And Akkaraman Lambs Fed Triticale, Hungarian Vetch Or A Mixture Of The Two Forages, Serkan Ates, Gurhan Keles, Fatma Inal, Ahmet Gunes, Mounir Louhaichi

IGC Proceedings (1977-2023)

Forages from Hungarian vetch and triticale monocultures or mixtures that can be produced with relatively low cost are important feed sources for ruminants in spring particularly in the arid and semiarid regions. The feed intake and the response of different sheep breeds (Fraser et al. 2009) to forage resources that vary in feeding value may differ. Therefore it is critical to match forage to animal and crop production needs for more efficient production in integrated crop livestock farming system.

Plant Biomass And Bovine Live Weight Changes In Mono-Specific And Mixed Pastures During The Rainy Season In Dry Tropical Mexico, Régulo Jiménez-Guillén, Adrián R. Quero-Carrillo, Pedro A. Martínez-Hernández, Alfonso Hernández-Garay

IGC Proceedings (1977-2023)

Dry tropics suffer long drought periods each year, negatively affecting the amount and digestibility of forage for cattle production. The aim of this study was evaluate different pasture types, grazed by cattle during the rainy season. Three hectares were prepared to compare: grass monoculture, Andropogon gayanus (G); a grass-legume mixture of A. gayanus and Clitoria ternatea (GL), and a grass-legume-tree mixture of A. gayanus, C. ternatea and Morus alba (GLT). Two grazing cycles (4 d grazing followed by 32 d resting; 72 d total) were completed. Three heifers (average initial weight 192 kg) grazed each experimental unit. The amounts …

Patch-Differentiation Of Vegetation And Nutrient Cycling In An Extensive Pasture System, Bettina Tonn, Anika Wirsig, Manfred Kayser, Nicole Wrage-Mönnig, Johannes Isselstein

IGC Proceedings (1977-2023)

In extensive grazing systems, ‘patch-grazing’ may lead to the development of a mosaic structure consisting of short, frequently defoliated, and tall, infrequently defoliated patches. If spatial patterns of sward structure are stable over time, this may result in a long-term differentiation of botanical composition and matter fluxes between patch types within a pasture. Patch dynamics, botanical composition and topsoil nutrient concentrations of different patch types were investigated in a long-term grazing experiment in the Solling hills, Germany, where differentiated grazing intensities have been applied for 10 years. Continuously stocked beef cattle grazed to target sward heights of 6 or12 cm …

Evaluating The Benefits Of Restricted Grazing To Protect Wet Pasture Soils In Two Dairy Regions Of New Zealand, Pierre C. Beukes, Alvaro J. Romera, David A. Clark, Dawn E. Dalley, Mike J. Hedley, David J. Horne, Ross M. Monaghan, Seth Laurenson

IGC Proceedings (1977-2023)

Many dairy farms in the Manawatu and Southland regions of New Zealand have poorly drained soils that are prone to treading damage, an undesirable outcome on grazed pastures during the wetter months of the year. Removing cows to a stand-off pad during wet conditions can reduce damage, but incurs costs. The objective of this study was to evaluate the impact of different levels of restricted grazing (from 0 to 10 hours grazing time/day for lactating cows) on pasture yield, damage and wastage, feed and stand-off expenses, and farm operating profit. A simulated farm from each region was used in a …

Restoring The Fire–Grazing Interaction Promotes Tree–Grass Coexistence By Controlling Woody Encroachment, Jane F. Capozzelli, James R. Miller, Diane M. Debinski, Walter H. Schacht

Department of Agronomy and Horticulture: Faculty Publications

Woody encroachment can convert grasslands and savannas to shrublands and woodlands, so understanding the processes which regulate woody encroachment is necessary to conserve or restore these ecosystems.We hypothesized that recreating the fire–grazing interaction would limit woody encroachment because focal grazing increases fuel accumulation on unburned areas and increases browsing on emergent woody plants in burned areas. This study was conducted in the Grand River Grasslands of Iowa and Missouri (USA) on 11 sites (15.4–35.0 ha). Each site was assigned to one treatment: patch-burn-graze (n = 4), with spatially discrete prescribed fires and free access by cattle (the fire–grazing interaction); graze-andburn …

Combination Of Biological And Chemical Soil Tests Best Predict Maize Nitrogen Response, M. D. Mcdaniel, Daniel T. Walters, L. G. Bundy, Xiaofei Li, Rhae A. Drijber, John E. Sawyer, Michael J. Castellano, C. A.M. Laboski, Peter C. Scharf

Department of Agronomy and Horticulture: Faculty Publications

Soil tests can help optimize nitrogen (N) fertilizer rates, thereby improving farmer profitability and environmental performance. In US Midwest maize (Zea mays) production, however, most soil N tests have limited accuracy to predict N fertilizer requirements. Here we tested the individual and combined ability of 30 soil tests (12 rapid N extractions, seven biological carbon or N tests, six long-term incubation kinetic parameters, and five other routine soil tests), as well as environmental and management data, to predict maize response to N fertilizer across 56 site-years in the US Midwest. Out of 30 soil tests, and across all …

Soybean Response To Water: Trait Identification And Prediction, Shawn Jenkins

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

The rising demand for soybean [Glycine Max (L.) Merrill] taken in consideration with current climatic trends accentuates the importance of improving soybean seed yield response per unit water (WP). To further our understanding of the quantitative WP trait, a multi-omic approach was implemented for improved trait identification and predictive modeling opportunities. Through the evaluation of two recombinant inbred line populations jointly totaling 439 lines subjected to contrasting irrigation treatments, informative agronomic, phenomic, and genomic associations were identified. Across both populations, relationships were identified between lodging at maturity (r = -0.58, H = 0.86), canopy to air temperature differential …

Effects Of Stocking Rate On The Variability Of Ecosystem Productivity In Desert Steppe, Zhongwu Wang, Shuying Jiao, Guodong Han, Mengli Zhao, Jing Wang, Walter D. Willms

IGC Proceedings (1977-2023)

Management practices can increase biodiversity and generate corresponding compensatory effects on biomass production, which may reduce inter-annual variability of productivity in some grassland ecosystems. However, it remains unclear how stocking rate influences variability of ecosystem productivity. Four stocking rates were compared in a completely randomized block experiment in the desert steppe of Inner Mongolia, China: non-grazed control (0 sheep/ha/mo), lightly grazed (LG, 0.15 sheep/ha/mo), moderately grazed (MG, 0.30 sheep/ha/mo) and heavily grazed (HG, 0.45 sheep/ha/mo). Aboveground net primary productivity (ANPP) was measured every August for eight consecutive years (2004-2011). ANPP decreased significantly (P < 0.05) with increasing stocking rate. Coefficients of variation for community (CV_comm) in LG and MG …

Sustainable Grazing Management For Temporal And Spatial Variability In North Australian Rangelands–A Synthesis Of The Latest Evidence And Recommendations, Peter O’Reagain, Joe C. Scanlan, Leigh Hunt, Robyn A. Cowley, Dionne Walsh

IGC Proceedings (1977-2023)

Rainfall variability is a major challenge to sustainable grazing management in northern Australia, with management often complicated further by large, spatially heterogeneous paddocks. This paper presents the latest grazing research and associated bio-economic modeling from northern Australia and assesses the extent to which current recommendations to manage for these issues are supported. Overall, stocking at around the safe long term carrying capacity will maintain land condition and maximize long term profitability. However, stocking rates should be varied in a risk-averse manner as pasture availability varies between years. Periodic wet season spelling is also essential to maintain pasture condition and allow …

Management Effects On The Vegetation Of Rangeland In The Middle Of Southern Slope Of Tianshan Mountains, Linqiao Xi, Shuqi Wu, Hui Liu, Dong Wang, Chunhui Ma

IGC Proceedings (1977-2023)

Rangeland degradation is a widespread problem and its restoration remains a major challenge. In recent years, many scientists have discussed the primary causes of over-grazing and approaches to restoration of China’s grasslands (e.g. Harris 2010; Wang and Han 2005; Lu et al. 2005). The major evidence of grassland degradation is lower plant productivity, reduced biodiversity and increase in poisonous weeds (Zhao et al. 2010), increased frequency of rodent and grasshopper infestations, and large scale dust storms (Lu et al. 2005). Restoration of these impacted ecosystems is an important and challenging task, especially in Xinjiang Province, China, …

Resource Variations Across The Landscape Mediate The Impact Of Grazing On Vegetation In Mongolian Rangeland Under High Climatic Variability, Kaoru Kakinuma, Tomoo Okayasu, Takehiro Sasaki, Undarmaa Jamsran, Toshiya Okuro, Kazuhiko Takeuchi

IGC Proceedings (1977-2023)

Assessment of grazing-induced degradation of arid and semi-arid rangelands with stochastic rainfall regimes is challenging. For the last two decades, rangeland ecologists have been discussing the relative importance of biotic and abiotic factors in controlling vegetation dynamics. According to the non-equilibrium concept, which emerged as a new paradigm to describe ecosystems in highly variable and poorly predictable environments, vegetation dynamics are driven primarily by abiotic factors such as rainfall, rather than by internal biotic regulation (e.g. grazing impact). Although a number of studies have emphasized the non-equilibrium nature of most rangelands, they have produced inconsistent results and there …