Forage sward structure of Mulato grass (Brachiaria hybrid ssp.) subjected to rotational stocking strategies

In ruminant-forage systems herbage allowance (HAL) has a major impact on grazing intensity and sward structure, affecting animals, plants, and ultimately, pasture yield. Data on HAL responses of tropical cultivated pastures are scarce and this information may be useful in optimizing pasture utilization. The objective of this study was to describe and contrast sward structure and herbage accumulation responses of 'Marandu' palisadegrass [Brachiaria brizantha (A.Rich.) Stapf] pastures to HAL during two grazing seasons (warm-rainy season of 2003 and 2004). Treatments were four daily HAL levels, 5, 10, 15 and 20 kg herbage mass per 100 kg live weight (%) in a rotational stocking system with 35 days of grazing cycle (28-day rest; 7-d grazing). Post-graze swards were shorter (~17 cm) under 5% HAL. For the other HAL levels, postgraze sward height increased throughout the experiment (21 to 50 cm). Changes in sward light interception (LI) were highly associated with height, but differed across HALs in 2004. Early in the 2003 season, HAL increases resulted in linear increase of the daily herbage accumulation rate (HAR; 47, 66, 78, and 98 kg DM ha-1 d-1 for 5, 10, 15 and 20%-HAL, respectively). For the subsequent grazing cycles of 2003 and all through 2004, HAR decreased with increasing HAL. This was associated with the excessive increase in sward height and mean forage mass, caused by lower grazing intensity. The use of lax (high) HAL to maximize animal performance, especially 10, 15 and 20%-HAL, resulted in decreased pasture performance (lower herbage accumulation, HAC) in palisadegrass pastures.

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The use of frequency estimates in studying sward structure

Grass and Forage Science ◽

10.1111/j.1365-2494.1992.tb02281.x ◽

1992 ◽

Vol 47 (4) ◽

pp. 358-365 ◽

Cited By ~ 6

Author(s):

J. H. NEUTEBOOM ◽

E. A. LANTINGA ◽

E. N. LOO

Keyword(s):

Sward Structure

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Effect of species composition and sward structure on the ingestive behaviour of cattle and sheep grazing South African sourveld

The Journal of Agricultural Science ◽

10.1017/s0021859600078047 ◽

1996 ◽

Vol 127 (2) ◽

pp. 271-280 ◽

Cited By ~ 9

Author(s):

P. J. O'Reagain ◽

B. C. Goetsch ◽

R. N. Owen-Smith

Keyword(s):

Species Composition ◽

Plant Height ◽

Functional Response ◽

Major Effect ◽

Intake Rate ◽

Sheep Grazing ◽

Bite Size ◽

Ingestive Behaviour ◽

Cattle And Sheep ◽

Sward Structure

SUMMARYThe effects of species composition and sward structure on the ingestive behaviour of cattle and sheep grazing a mesic, low quality grassland in South Africa were investigated over the 1990–93 grazing seasons. Species composition had a significant (P < 0·05) effect on sheep bite size and on cattle and sheep bite rates but had no effect on dry matter intake rate (IR). Species composition could, however, affect IR over longer grazing periods than those used in the experiment.Sward structure had a major effect on ingestive behaviour. Cattle and sheep bite rates and cattle grazing time, were negatively correlated (P < 0·05) with plant height but positively correlated (P < 0·05) with sward greenness. Bite size and hence IR in cattle and sheep were strongly correlated (P < 0·001) with plant height. Cattle IR increased from 6 to 20g/min over the range of heights encountered and appeared to reach an asymptote at a plant height of 20–25 cm. Sheep IR, expressed per unit of body mass, increased from 0·01 to an asymptote or maximum of 0·13 g/min/kg at plant heights of 10–15 cm. For sheep there was evidence of a non-asymptotic functional response at some sites with IR being maximized at certain sward heights but declining thereafter. This suggests the possible existence of a third, quality dimension to the functional response on these low-quality grasslands.

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Post‐grazing cutting management in tall fescue affects the sward structure, forage and liveweight production

Grass and Forage Science ◽

10.1111/gfs.12447 ◽

2019 ◽

Vol 74 (4) ◽

pp. 661-669

Author(s):

Jorge Omar Scheneiter ◽

Jonatan Nicolás Camarasa ◽

Daniel Aperlo ◽

Martín Alejandro Ferrari ◽

Martín Nalino ◽

...

Keyword(s):

Tall Fescue ◽

Cutting Management ◽

Sward Structure

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Sward structure and diet selection after sheep introduction on abandoned grassland in the Giant Mts, Czech Republic

Biologia ◽

10.2478/s11756-008-0076-1 ◽

2008 ◽

Vol 63 (4) ◽

Cited By ~ 9

Author(s):

Michal Hejcman ◽

Irena Žáková ◽

Miloslav Bílek ◽

Pavla Bendová ◽

Pavla Hejcmanová ◽

...

Keyword(s):

Plant Species ◽

Diet Selection ◽

Mountain Grassland ◽

Veratrum Album ◽

Preferred Species ◽

Abandoned Grassland ◽

Species Occurrences ◽

Drinking Place ◽

Sward Structure

AbstractThe effect of rotational grazing on the sward structure of long-term abandoned grassland and the sheep diet selection were investigated in the Giant Mts (Krkonoše/Karkonosze). The aim of the study was to answer the following questions: (1) Does sheep grazing affect the sward structure of previously abandoned mountain grassland? (2) How does sheep diet selection develop within and among grazing seasons? (3) Which section of a pasture do sheep prefer to graze? Data was collected three times during each grazing season in spring, summer and in autumn in the years 2001, 2002 and 2003 Fifty 1 × 1 m plots were used where the plant species occurrence and damage of plants by grazing for all species were repeatedly recorded. 1) Nonsignificant changes in plant species occurrences were recorded in spite of obvious visual changes in sward structure due to grazing e.g. the retreat of tall dominant species characteristic of long-term unmanaged grasslands. 2) Seasonal as well as inter-annual changes in sheep diet selection were detected. In spring 2001, sheep grazed over a wide variety of plant species in low quantities. In subsequent springs, they preferred species favoured during previous autumns (Veratrum album subsp. lobelianum; Ranunculus platanifolius; Senecio ovatus) and changed the diet only as a result of the elimination of favoured plants. 3) Sheep preferred to graze at the highest elevated part of the pasture probably as a consequence of anti-predator behaviour not due to higher occurrence of favoured plant species or the presence of a drinking place or salt licks. Changes in the sward structure were mostly of a quantitative not qualitative character, thus the presence-absence data collection is not a suitable method for monitoring the effects of management restoration. The diet selection changed probably due to the animals’ experience; sheep had no experience with montane species in spring 2001. The sheep were able to recognize favoured plant species after 6 months of wintering in lowland.

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