Synthesis of system outcomes for a grazing-management experiment in temperate native pastures

2017 ◽  
Vol 57 (9) ◽  
pp. 1869 ◽  
Author(s):  
W. B. Badgery ◽  
D. L. Michalk

Increasing the intensity of grazing management from continuous grazing or set-stocking to intensive rotational grazing has been proposed as a way of improving the profitability and environmental outcomes for native pasture-based grazing systems in the high-rainfall zone (HRZ) of southern Australia. The present paper synthesised the results and outcomes of eight papers covering different aspects of a grazing-system study investigating the intensity of grazing management at Panuara (33°27ʹS, 148°56ʹE), 25 km south-west of Orange, New South Wales. The systems analysis covered soils and soil water, pastures, animal production, profitability and business risk by using a combination of field experiments and biophysical modelling. The experimental approach, engagement with stakeholders and the potential impact of the research outcomes are discussed; as are the future directions for grazing system research. Increasing the intensity of grazing management from a 1- to a 20-paddock system resulted in a 21% higher pasture growth, 22% higher stocking rate and 20% higher lamb production per hectare. However, modelling demonstrated that seasonal variability had a greater impact on profitability than did the management system, and whole-farm profitability of the 20-paddock system was lower than that of the 1- and 4-paddock systems due to higher infrastructure costs. Pasture stability was associated with a high perennial grass content (>70%), and a stocking rate of 4.2 ewes/ha for continuous grazing or 5.3 ewes/ha for intensive rotational grazing limited the potential for degradation events. Advantages were identified in fencing and managing production zones, with different production potential within a farm, to improve utilisation across the landscape and efficiency of fertiliser use. The farming-system approach successfully integrated field research with pre- and post-experimental modelling, and with strategic input from an advisory group containing farmers, researchers and advisors, to develop a full understanding of the impact, at a system level, of increasing the intensity of grazing management in the HRZ.

1963 ◽  
Vol 61 (2) ◽  
pp. 147-166 ◽  
Author(s):  
C. P. McMeekan ◽  
M. J. Walshe

1. A large-scale grazing management study comparing rotational grazing and continuous grazing with dairy cows at two stocking rates over four complete production seasons is described.2. The four treatments were: (i) controlled grazing, light stocking rate; (ii) controlled grazing, heavy stocking rate; (iii) uncontrolled grazing, light stocking rate; (iv) uncontrolled grazing, heavy stocking rate.Each treatment involved 40 cows for a first 2-year phase and 42 cows for the following 2 years. Each herd had a normal age distribution pattern and seven 2-year-old first lactation heifers (17% of total herd) were introduced each year to maintain this pattern.3. Stocking rate was the more important factor affecting the efficiency of pasture utilization as measured by per acre output of milk and butterfat. In general, high stocking was associated with higher outputs per acre despite lower yields per animal.4. Grazing method was of less importance. In general, controlled rotational grazing was superior to uncontrolled continuous grazing, both per animal and per acre, but the average influence even of these extremes of management was only half that of stocking rate.5. Significant interactions between stocking rate and grazing method existed. Under continuous grazing a point was reached where production per acre declined to the vanishing point with increased stocking rate due to excessive depression of per cow yield: this point was not reached under rotational grazing at the same high stocking levels.6. The results suggest that optimum stocking rate under rotational grazing occurs at a level some 5–10% higher than under continuous grazing. A depression of 10–12% in per cow yield, compared with more lenient grazing, corresponds with optimum stocking level irrespective of the grazing system. This estimate is suggested as a guide line in applying the principles involved.


1967 ◽  
Vol 7 (28) ◽  
pp. 434
Author(s):  
WR McManus

Concentrations of total nitrogen and total volatile fatty acids in the rumen fluid of sheep grazing improved pastures were measured for ten months in a dry year on the southern tablelands of New South Wales, and the concentrations of nitrogen and volatile fatty acids (V.F.A.) were related to season, wool production, and grazing management. The observations were made during two long-term grazing management experiments. In the first experiment four groups of breeding Merino ewes grazed a Wimmera ryegrass-subterranean clover (Lolium rigidum Gaud.-Trifolium subterraneum L.) pasture. A deferred grazing system (autumn saving) of pasture management was compared with continuous grazing at stocking rate treatments equivalent to 7.0 and 3.5 ewes to the acre. In the second experiment two groups of Merino weaners grazed a Phalaris tuberosa-subterranean clover pasture at a stocking rate equivalent to 8.6 sheep to the acre. One group received a hay supplement, the other did not. In both experiments nitrogen values were low between late autumn and mid-winter and again between late spring and summer, and high in early autumn and again in spring (P<0.05). The low levels were about 55 per cent of peak autumn and spring levels in (experiment 1) and 60 per cent of peak autumn and spring levels in (experiment 2). Total V.F.A. did not vary significantly between seasons in either experiment. At the higher stocking rate the ewes had lower levels of rumen total nitrogen than at the lower stocking rate. V.F.A. did not vary consistently between stocking rates. At both stocking rates ewes on the autumn saving system of grazing management had more nitrogen in the rumen fluid during late pregnancy and early lactation than did those on the continuous grazing system (P<0.001). After the ewes had access to the saved pasture, autumn saving resulted in a higher concentration of volatile fatty acids than continuous grazing (P< 0.05). Although feeding a hay supplement benefited the weaners the concentrations of total nitrogen in the rumen fluid of the two groups of sheep were similar. There was a fairly consistent tendency for the group receiving hay to have lower concentrations of volatile fatty acids in their rumen fluid. Possible reasons for these effects are discussed.


2001 ◽  
Vol 41 (2) ◽  
pp. 161 ◽  
Author(s):  
H. Lloyd Davies ◽  
I. N. Southey

Border Leicester x Merino ewes joined to Dorset Horn rams were grazed for 3 years on subterranean clover-based pastures established on virgin ground at Bakers Hill, Western Australia, at 3 stocking rates and 2 systems of grazing management (viz. continuous grazing compared with a deferred grazing system which was designed to ensure that pasture availability met the nutritional requirements of breeding ewes at critical phases of their reproductive cycle). Both stocking rate and grazing management affected pasture availability: there was always a greater amount of pasture available on offer under the deferred grazing system. However, this extra pasture rarely increased animal production; the effect of the deferred grazing compared with continuous grazing was inconsequential for ewe liveweight in late pregnancy and for lamb growth rate. The deferred grazing system promoted grass dominance at all stocking rates whereas there was only 24% grass under continuous grazing at the high stocking rate. Stocking rate on some occasions affected ewe liveweight at joining but always affected the prelambing weight. The highest stocking rate on some occasions reduced twinning rate. Stocking rate (particularly in 1966) affected lamb growth rate. The combination of the effect of stocking rate on twinning rate, lamb survival and lamb growth rate resulted in a lower proportion of lambs achieving 30 kg liveweight per lamb marked at higher stocking rates (3-year mean low stocking rate 106% lambs marketed; medium stocking rate 95% and high stocking rate 80%). In 1966, total plasma ketones were lower and plasma glucose (measure of ewe metabolic status) was higher on the deferred system than on the continuously grazed system.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Yingxin Wang ◽  
Hang Yuan ◽  
Xinglu Zhang ◽  
Yi Sun ◽  
Shenghua Chang ◽  
...  

AbstractDigging and mound-building by rodents lead to considerable disturbances in the topsoil and may affect plant composition, soil properties. However, little is known about the effects of these activities on GHG emissions, especially under different grazing management. This paper aimed to measure changes in CO2 and CH4 efflux with varying grazing management during the warm and cold seasons and to relate CO2 and CH4 efflux to pika burrow density and zokor mound density with different grazing management. Results of this study showed that CO2 efflux was significantly affected by the grazing season, whereas CH4 efflux was significantly affected by the grazing system. There were significant relationships between GHG efflux and rodent population density which were regulated by grazing management. CO2 efflux increased linearly with rodent density under seasonal continuous grazing in warm season. CO2 and CH4 efflux and rodent population density showed a significant quadratic convex relationship under rotational grazing at 24 SM/ha in warm and cold seasons and rotational grazing at 48 SM/ha in cold season. Under rotational grazing at light stocking rate (24 SM/ha), appropriate populations of rodents were beneficial for decreasing GHG emissions. This results also used to help drive a best-practices model for grazing practices of local herders.


2008 ◽  
Vol 40 (1) ◽  
pp. 301-313 ◽  
Author(s):  
Jeffrey M. Gillespie ◽  
Wayne Wyatt ◽  
Brad Venuto ◽  
David Blouin ◽  
Robert Boucher

Comparisons are made concerning labor required and profitability associated with continuous grazing at three stocking rates and rotational grazing at a high stocking rate in the U.S. Gulf Coast region. A unique data set was collected using a time and motion study method to determine labor requirements. Profits are lowest for low stocking rate–continuous grazing and high stocking rate–rotational grazing. Total labor and labor in three specific categories are greater on per acre and/or per cow bases with rotational-grazing than with continuous-grazing strategies. These results help to explain relatively low adoption rates of rotational grazing in the region.


1966 ◽  
Vol 67 (2) ◽  
pp. 199-210 ◽  
Author(s):  
A.G. Campbell

1. Net pasture dry matter production and available pasture dry matter were measured over 3 years in a small-scale replica of the study of the effects of dairy cow grazing management and stocking rate reported by McMeekan & Walshe (1963).2. The four treatments were(i) Controlled rotational grazing, light stocking rate (0.95 cows/acre).(ii) Controlled rotational grazing, heavy stocking rate (1.19 cows/acre).(iii) Uncontrolled, set stocked grazing, light stocking rate (0.95 cows/acre).(iv) Uncontrolled, set stocked grazing, heavy stocking rate (1.19 cows/acre).3. The pasture measurement technique employed measured net pasture production (gains through new growth minus losses from all sources). It is argued that this parameter, rather than absolute pasture production, governs the changes in the dry matter feed supply to the grazing animal.


2010 ◽  
Vol 39 (7) ◽  
pp. 1548-1557 ◽  
Author(s):  
Nelson Massaru Fukumoto ◽  
Julio Cesar Damasceno ◽  
Fermino Deresz ◽  
Carlos Eugênio Martins ◽  
Antônio Carlos Cóser ◽  
...  

The objective of this study was to evaluate milk yield and composition, dry matter intake, and stocking rate in pastures with tanzania grass (Panicum maximum cv. Tanzânia), star grass (Cynodon nlemfuensis cv. Estrela-Africana), and marandu grass (Brachiaria brizantha cv. Marandu). The grasses were managed in a rotational grazing system with Holstein x Zebu crossbreed cows, with a 30-day resting period and three days of paddock occupation. The pastures were fertilized with 1,000 kg/ha/year using the 20:05:20 (NPK) formula, split in three applications during the rainy season. It was used a complete random block experimental design with three factors being studied and two replications. In the experiment, four cows/paddock were used and, when it was necessary, regulator animals were added in order to obtain a supply of 7% body weight green forage dry matter. The animals were individually fed concentrate at 2 kg/day during the experimental period. Milk yield did not differ among the three grasses, with values of 9.1; 9.1; and 8.7 kg/cow/day for pastures with tanzania grass, star grass and marandu grass, respectively. Similarly, grass did not affect milk chemical composition. Stocking rate was similar among the three grasses, with values of 4.6; 4.5 and 5.0 UA/ha for tanzania grass, star grass and marandu grass, respectively. The highest dry matter intake was observed for tanzania grass with 2.6% of the body weight while stargrass (2.3%) and marandu grass (2.4%) did not differ among each other. The highest dry matter intake on tanzania grass pasture was not reflected on milk yield per animal. Milk yield and composition and stocking rate are similar among the evaluated grasses.


2018 ◽  
Vol 58 (12) ◽  
pp. 2269 ◽  
Author(s):  
D. Real ◽  
C. M. Oldham ◽  
A. van Burgel ◽  
E. Dobbe ◽  
J. Hardy

Tedera (Bituminaria bituminosa C.H Stirt. vars. albomarginata and crassiuscula) is a traditional forage species for goats in the Canary Islands, Spain. It has agronomic characteristics ideally suited to Mediterranean-like climates that allows it to provide high quality green forage for grazing animals during summer and autumn. It can be used to extend the growing season into late spring and early summer and/or to reduce or eliminate the need for expensive hand feeding of grain and hay to sheep to fill the ‘feed gap’ during the dry season in southern Australian farming systems. Three sheep grazing experiments were carried out with the objective to evaluate sheep production during summer and autumn with tedera as the sole diet. A 3-ha site at Dandaragan, Western Australia was grazed during the summer and autumn of 2014–2015 and 2016 and a 2.4-ha site was grazed at Kojonup, Western Australia during the same period in 2016. At each site, two grazing treatments were evaluated, continuous grazing and rotational grazing with six plots (14 days of grazing and 70 days of recovery). The first hypothesis tested was that tedera plants would not survive continuous grazing during summer and autumn. The second hypothesis tested was that without hand feeding, 10 dry sheep equivalents/ha would be able to at least maintain weight and condition score during summer and autumn. The third hypothesis tested was that rotational grazing would improve the production of the sheep (liveweight and condition score) compared with continuous grazing. The first hypothesis was rejected, the population of tedera plants did not significantly decline due to being continuously grazed during summer and autumn. The second hypothesis was confirmed, at the three experimental sites, 10 dry sheep equivalents/ha were able to at least maintain weight and condition score without any hand feeding. The third hypothesis was partially rejected; continuous grazing had a better performance of the sheep than rotational grazing. However, the rotational grazing plots had more tedera on offer in the remaining grazing plots in the rotation with the potential for a longer grazing time. These three experiments clearly demonstrate that tedera can be used to reduce or eliminate expensive hand feeding during summer and autumn using the simplest and least expensive grazing management; continuous grazing.


2013 ◽  
Vol 53 (8) ◽  
pp. 856 ◽  
Author(s):  
T. Coventry ◽  
H. Sutherland ◽  
M. Waters ◽  
P. Dutton ◽  
B. Gream ◽  
...  

The Cicerone Project began as a producer-led partnership that sought, over a period of 8 years, to enhance the profitability and sustainability of livestock enterprises by improving the connection between those producers, research and extension. Following a detailed survey, the research and extension needs of livestock producers were identified and several applied investigations were conducted to meet those needs and delivered through a range of extension activities. This final paper of the Cicerone Special Issue reflects on the entire Project from a wide array of perspectives, including livestock producers, researchers, extension specialists and staff employed by the Project, all of whom are authors of this paper. A notable early successful outcome of the Project was the improved precision of footrot diagnosis, which has been of value to the entire sheep industry, and that flowed from a field investigation of benign and virulent footrot combined with detailed genetic investigations, which led to an improved testing regime. This paper also reflects on the findings of an unreplicated agricultural ecosystem research trial, which measured the impact of pasture renovation, increased soil fertility and grazing management on the profitability and sustainability of three different 53-ha farmlets. Valuable findings from this whole-farmlet trial included the need for a high quality feed supply for increasing stocking rate and animal liveweights; the ability and utility of satellite imagery to detect changes in pasture growth, composition and recent grazing pressure; the value of short grazing and long rest periods for controlling Barber’s pole worms of sheep; the impact of increased stocking rates on whole-farm profitability and risk; methods of optimising decisions relating to pasture renovation, fertiliser applications and grazing management; and an integrated analysis of all key measured components of the farmlet management systems. Collectively, these findings were powerful as they were demonstrated at a scale credible to livestock producers using the ‘compare – measure – learn – adopt’ approach, which was the key philosophy adopted by the Cicerone Project. By comparing and measuring different whole-farm systems, and by ensuring that producers had ownership of the trial process, the Project successfully delivered objective findings that producers trusted and which increased our understanding of important drivers of complex grazing enterprises under variable climatic conditions. Some of these drivers included: the influence of soil phosphorus on botanical composition and subsequent livestock production, the role of pasture renovation and soil fertility on herbage supply, herbage quality and stocking rate, and the improved gastrointestinal nematode control delivered by intensive rotational grazing. The beneficiaries of the Project included the 180 farmer members who participated in some 61 field days and workshops; the research and extension collaborators including four postgraduates who completed their research investigations in conjunction with the Project; and some 500 undergraduate and 300 technical students who benefited from coming to understand the applied field comparisons of the three whole-farmlet systems. Having livestock producers play a significant leadership role led to valuable outcomes achieved with research collaborators; this should encourage the development of other learning partnerships which aim to explore complex farming system issues.


2011 ◽  
Vol 49 (No. 1) ◽  
pp. 18-23 ◽  
Author(s):  
S. Hejduk ◽  
F. Hrabě

Problems concerning total dry weight and distribution of underground phytomass were studied in a pasture trial at Rapotin near &Scaron;umperk, the CzechRepublicin the period 1995&ndash;1999. The total weight of dry underground pasture phytomass (DUP) was 976 g/m<sup>2</sup> (5-year average) in a soil layer of 0&ndash;200 mm (both live and dead roots). The DUP was significantly increased by mineral fertilizers (90 kg N/ha, 30 kg P/ha a 90 kg K/ha). The weight of DUP was not significantly influenced by a grazing system, renewal or resowing of the original grassland. In unfertilized plots, DUP weight amounted to 989 g/m<sup>2</sup>, i.e. 92 g/m<sup>2</sup> (8.6%) less than in fertilized plots in the period 1996&ndash;1999. In the same period, under the grassland exploited by rotational grazing 1142 and under continuous grazing 1082 g/m<sup>2</sup> DUP were determined, i.e. by 60 g/m<sup>2</sup> (5.5%) less. The highest DUP weight in the period 1996&ndash;1999 was found in autumn 1997 (1222 g/m2) immediately before achieving the maximum forage yield in May 1998. In a layer of 0&ndash;20 mm, 54.6% of the total DUP was found. In this surface layer, significant increase in the DUP weight was found in fertilized plots. In 1999, some 88.5 and 90.2% of DUP were concentrated in unfertilized (903 g/m<sup>2</sup>) and fertilized (952 g/m<sup>2</sup>) plots, respectively in a layer of 0&ndash;100 mm.


Sign in / Sign up

Export Citation Format

Share Document