Tillering dynamics in Guinea grass pastures subjected to management strategies under rotational grazing

SUMMARYPlants’ ability to rebuild their tiller population is affected by weather changes and management strategies. The hypothesis of the present study was that frequency and severity of defoliation alter Mulato grass (Brachiaria ruziziensis × Brachiaria brizantha cv. Marandu) sward development, and the proportion of aerial and basal tillers, interfering with sward stability. The objective was to evaluate aerial, basal and total tiller population density and changes in tillering dynamics. Treatments corresponded to strategies of rotational grazing characterized by combinations between two pre-grazing (95% and maximum canopy light interception during regrowth; LI95% and LIMax) and two post-grazing conditions (15 and 20 cm stubble height). The experimental period comprised four seasons of the year: summer 2008 (February–March 2008); autumn–early spring (April to mid-November 2008); late spring (mid-November–December 2008); and summer 2009 (January–March 2009). Density of aerial tillers decreased from summer 2008 to late spring. Tiller death decreased from summer 2008 to autumn–early spring. Aerial and total tiller death increased from late spring to summer 2009, mainly for the LI95% treatment. No differences were observed in the tiller population stability index of aerial tillers for LI treatments or post-grazing heights. The balance between tiller appearance and death for basal tillers remained relatively stable from summer 2008 to late spring. For aerial tillers the balance decreased to negative values from summer 2008 to autumn–early spring for both LI treatments. For total tiller population, the balance decreased to negative values from summer 2008 to autumn–early spring. Results indicated a strong seasonal effect on Mulato grass tillering and growth. Tillering dynamics were affected primarily by grazing frequency, which changed the relative importance of basal and aerial tillers. The results suggested that basal tillering was the predominant perennation pathway.

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A biophysical dairy farm model to evaluate rotational grazing management strategies

Agronomie ◽

10.1051/agro:2002071 ◽

2003 ◽

Vol 23 (2) ◽

pp. 105-122 ◽

Cited By ~ 34

Author(s):

Marie-Jos�e Cros ◽

Michel Duru ◽

Fr�d�rick Garcia ◽

Roger Martin-Clouaire

Keyword(s):

Management Strategies ◽

Dairy Farm ◽

Grazing Management ◽

Rotational Grazing ◽

Farm Model

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Livestock weights in response to three whole-farmlet management systems

Animal Production Science ◽

10.1071/an12201 ◽

2013 ◽

Vol 53 (8) ◽

pp. 727 ◽

Cited By ~ 23

Author(s):

G. N. Hinch ◽

J. Hoad ◽

M. Lollback ◽

S. Hatcher ◽

R. Marchant ◽

...

Keyword(s):

Soil Fertility ◽

Management Strategies ◽

Experimental Period ◽

Supplementary Feeding ◽

Grazing Management ◽

Stocking Rate ◽

Rotational Grazing ◽

Average Value ◽

Management Regime ◽

Similar Range

This paper reports changes in livestock weights recorded in a whole-farmlet experiment, which aimed to examine the profitability and sustainability of three different pasture and grazing management strategies. The assessment of liveweights was considered a key component of measuring the integrated effects of the farmlet-scale treatments. The three farmlets comprised a typical management regime, which employed flexible rotational grazing over eight paddocks with moderate soil fertility (farmlet B), a system based on the same grazing management and paddock number but with higher levels of sown pasture and soil fertility (farmlet A) and a farmlet with moderate soil fertility and intensive rotational grazing over 37 paddocks (farmlet C). Early in the experimental period, there were no significant differences between farmlets in the liveweight of any class of livestock. However, from the second year onwards, as the pasture renovation, soil fertility and grazing management treatments took effect, differences in liveweight between farmlets became more apparent and significant. The stocking rate, which was treated as an emergent property of each farmlet, reached a maximum annual average value after 5 years of 12.6, 8.5 and 7.7 dry sheep equivalents (dse)/ha on farmlets A, B and C representing 84, 113 and 51% of their respective target stocking rates which were 15, 7.5 and 15 dse/ha. The liveweights of ewes, both before joining and during pregnancy, varied with year and farmlet with those on farmlets A and B tending to be significantly heavier than those on farmlet C. From 2003 to 2006, liveweights were significantly (P < 0.001) affected by a wide array of factors and their interactions including: date, ewe age, green digestible herbage, legume herbage mass, proportion of farmlet grazed, stocking rate and level of supplementary feeding. The weights of lambs/weaners/hoggets, both pre- and post-weaning, were at times also higher on farmlets A and B compared with those on farmlet C and were affected by a similar range of factors to those which affected ewe weights. Similar relative differences also applied to the liveweights of the other livestock run on the farmlets, namely wethers and non-reproductive cattle. The results suggest that stocking rate was able to be increased towards the higher target of farmlet A due to the higher level of pasture renovation and soil fertility on that farmlet, which led to high liveweights per head as well as the higher stocking rate. However, as the stocking rate increased on farmlet A, the differences between farmlets in liveweight per head diminished and the need for supplementary feeding increased. In contrast, the intensive rotational grazing practised on farmlet C did not allow the farmlet to increase its stocking rate towards its higher target. It appears that the higher proportion of each of farmlets A and B grazed at any one time allowed all classes of livestock to reach higher liveweights per head than on farmlet C, due presumably to the greater proportion of those two farmlets grazed at any one time.

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Simulation of rotational grazing to evaluate integrated pest management strategies for Boophilus microplus (Acari: Ixodidae) in Venezuela

Veterinary Parasitology ◽

10.1016/s0304-4017(00)00282-x ◽

2000 ◽

Vol 92 (2) ◽

pp. 139-149 ◽

Cited By ~ 11

Author(s):

F Hernández-A ◽

P.D Teel ◽

M.S Corson ◽

W.E Grant

Keyword(s):

Integrated Pest Management ◽

Pest Management ◽

Management Strategies ◽

Boophilus Microplus ◽

Rotational Grazing

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Changes in botanical composition on three farmlets subjected to different pasture and grazing management strategies

Animal Production Science ◽

10.1071/an11177 ◽

2013 ◽

Vol 53 (8) ◽

pp. 670 ◽

Cited By ~ 22

Author(s):

L. M. Shakhane ◽

J. M. Scott ◽

R. Murison ◽

C. Mulcahy ◽

G. N. Hinch ◽

...

Keyword(s):

Soil Fertility ◽

Initial Conditions ◽

Management Strategies ◽

The Other ◽

Grazing Management ◽

Curvilinear Relationship ◽

Botanical Composition ◽

Rotational Grazing ◽

Tall Grass ◽

Soil P

As part of the Cicerone Project’s farmlet experiment, conducted on the Northern Tablelands of New South Wales, Australia, between July 2000 and December 2006, this study assessed the effects of varying soil fertility, pasture species and grazing management on the botanical composition of three 53-ha farmlets subjected to different management strategies. Starting with the same initial conditions, the farmlets were managed to reach different target levels of soil phosphorus (P) and sulfur (S); Farmlet A aimed at 60 mg/kg of Colwell P and 10 mg/kg S (KCl40) whereas Farmlets B and C both aimed at 20 and 6.5 mg/kg of P and S, respectively. Pastures were renovated on six out of eight paddocks on Farmlet A, but only one paddock of each of Farmlets B (typical management) and C (intensive rotational grazing) was renovated. Flexible rotational grazing was employed on Farmlets A and B (each of eight paddocks) while Farmlet C used intensive rotational grazing over its 17 major paddocks, which were further subdivided into 37 subpaddocks. This paper focuses on the botanical composition dynamics observed across all three farmlets and the explanatory variables associated with those changes. Eight assessments of botanical composition were carried out at approximately annual intervals across each of the 37 major paddocks distributed across the farmlets and the results for each of 49 species were aggregated into seven functional groups for analysis. The strongest correlation found was a negative curvilinear relationship between sown perennial grasses (SPG) and warm-season grasses (WSG). The most significant factors affecting the functional group changes were soil P, sowing phase, paddock and date. These factors led to significant increases in SPG and correspondingly lower levels of WSG on Farmlet A compared with Farmlet B. Farmlets B and C experienced similar, declining levels of SPG, and increasing levels of WSG suggesting that intensive rotational grazing did not lead to substantial changes in botanical composition, compared with flexible rotational grazing, in spite of the fact that intensive rotational grazing had much longer grazing rests and shorter graze periods than the other two farmlets. Soil P levels were also significantly associated with levels of cool-season annual grasses, legumes and herbs, especially on Farmlet A. In general, the largest differences in botanical composition were between Farmlet A and the other two farmlets; these differences were most closely associated with those plants categorised as sown, introduced, C3 pasture species. The levels of legume were generally low on all farmlets, due largely to the dry seasons experienced over most of the trial. Efforts to increase the legume composition on all farmlets were more successful on Farmlet A than on the other two farmlets due, presumably, to higher soil fertility on Farmlet A. Farmlet C, with its long rest periods and short graze periods, had a small proportion of legumes, due to the competitive effects of the accumulated tall grass herbage between grazings. The ‘typical’ management of Farmlet B also resulted in low levels of legume as well as increased ‘patchiness’ of the pastures and increased numbers of thistles.

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Simulating management strategies: the rotational grazing example

Agricultural Systems ◽

10.1016/j.agsy.2003.06.001 ◽

2004 ◽

Vol 80 (1) ◽

pp. 23-42 ◽

Cited By ~ 31

Author(s):

M.J Cros ◽

M Duru ◽

F Garcia ◽

R Martin-Clouaire

Keyword(s):

Management Strategies ◽

Rotational Grazing

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Influence of Nitrogenous Fertilizers on Guinea Grass Yield and Carrying Capacity in Lajas Valley

The Journal of Agriculture of the University of Puerto Rico ◽

10.46429/jaupr.v42i4.12604 ◽

1969 ◽

Vol 42 (4) ◽

pp. 239-247 ◽

Cited By ~ 1

Author(s):

L. Rivera-Brenes ◽

E. N. Colón-Torres ◽

F. Gelpí ◽

J. Torres-Más

Keyword(s):

Ammonium Sulfate ◽

Carrying Capacity ◽

Block Design ◽

Grazing Management ◽

Annual Rainfall ◽

Semiarid Region ◽

Rotational Grazing ◽

Randomized Block Design ◽

Dry Spells ◽

Guinea Grass

The Lajas Valley is a semiarid region located in the southwestern corner of the Island. Annual rainfall fluctuates from 40 to 60 inches with rather prolonged dry spells. Guinea grass is the prevailing and most important pasture forage. Very little or no fertilizer at all is used and, generally speaking, the grazing management is poor. In 1952, an experiment was started with Guinea grass submitted to different fertilizer treatments, under rotational grazing. A randomized-block design already described in another paper (3) was used and each treatment of 0, 40, and 80 pounds of nitrogen per acre was applied as ammonium sulfate every 4 months was replicated three times. Results obtained indicate that fertilization pays even in this relatively dry section of the Island.

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Effect of grazing management strategies on the yield and nutritional value of Marandu grass in the semiarid of Brazil

Semina Ciências Agrárias ◽

10.5433/1679-0359.2021v42n4p2503 ◽

2021 ◽

Vol 42 (4) ◽

pp. 2503-2522

Author(s):

Maria Catiane Silva Veloso Araújo ◽

◽

Eleuza Clarete Junqueira de Sales ◽

Flávio Pinto Monção ◽

Vicente Ribeiro Rocha Júnior ◽

...

Keyword(s):

Dry Matter ◽

Nutritional Value ◽

Accumulation Rate ◽

Structural Characteristics ◽

Block Design ◽

Management Strategies ◽

Grazing Management ◽

Rotational Grazing ◽

Pasture Management ◽

Sward Height

The objective of this study was to evaluate the effects of two grazing management strategies on structural, productive and nutritional parameters of Marandu grass (Urochloa brizantha cv. Marandu). A completely randomized block design with two pasture management strategies and eight replications (blocks) was used. The grazing management strategies were: (1) low intensity rotational grazing (LI), with a pre-grazing sward height of 40 cm and a post-grazing sward height of 24 cm, i.e., a defoliation intensity of 50%; (2) High intensity rotational grazing (HI), with a pre-grazing sward height of 40 cm and a post-grazing sward height of 10 cm (±70% defoliation intensity). Pastures were sampled before and after grazing for estimation of forage mass, forage accumulation rate, structural characteristics, nutritional value and dry matter intake.The LI strategy resulted in higher dry matter production than HI before (18.33%) and after grazing (49.06%), increasing pre-grazing forage density by 13.21% (P < 0.05). The production of potentially digestible dry matter was highest (P < 0.05) in LI strategy (21.3% before and 39.6% after grazing, respectively). Higher post-grazing green forage mass (45%) increased the residual crude protein in LI. The LI management strategy increased forage mass production and can be used in Marandu grass pastures.

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