The Duration of Regrowth Period and the Structural Traits in a Rotationally Grazed \u3ci\u3ePanicum maximum\u3c/i\u3e Sward

Panicum maximum \u27cv\u27. Mombaça was rotationally grazed by steers. Three regrowth periods based on the number of expanded leaves per tiller: 2.5; 3.5 and 4.5, were compared. Three groups of seven tester steers, one for each treatment, grazed the replications of each experimental paddocks, the animals being removed from a paddock after 4 to 5 day grazing period when its sward leaf area index (LAI) was 1.5, on the average. Sward height and available biomass increased while tiller population density and leaf-stem ratio decreased with regrowth period. Overall averages observed for LAI and photosyntheticly active radiation interception by the end of regrowth periods did not differ among treatments but LAI and light interception evolved faster in the swards submitted to the shortest regrowth period towards the end of the grazing season

Desmanthus: A New Forage Legume to Improve Wool Growth in Tropical Australia

In tropical Australia, very short and erratic wet seasons are the critical factors in determining forage growth and animal production (Wheeler & Freer, 1986). Grasses are highly susceptible to low rainfall and animal production in such conditions become strictly seasonal. Improvements in meat and wool production by the introduction of stylo species (Stylosanthes sp.) into natural grasslands have been intensively reported (Gillard & Winter, 1984). However, there are currently no suitable introduced legumes for the c.28 million ha of Mitchell grass (Astrebla spp.) plains in heavy clay soils of western North Queensland, grazed predominately by wool producing Merino sheep (Phelps, 1999). Members of the genus Desmanthus appear to offer the possibility for filling this role (Gardiner et al., 2004). This work aimed to evaluate the potential of four Desmanthus accessions, in comparison with Verano stylo (Stylosanthes hamata cv. Verano), as alternative supplements for diets of Mitchell grass hay fed to Merino wethers in western North Queensland

Morphogenetic and Structural Characteristics of Clones of Elephant Grass Managed under Intermittent Stocking

Morphogenetic studies of the growth dynamics of leaves and tillers of forage grasses have enabled the management strategies for grasses to be defined for various environmental conditions (Euclides et al. 2010). As the development of clones of Pennisetum purpureum is recent (Pereira e Lédo 2008), detailed information on their growth characteristic under pasture is necessary as a reference for the adoption of appropriate management practices. The objective of this study was to assess the morphogenetic and structural characteristics of basal and aerial tillers in pastures of two small-size clones of elephant grass managed under intermittent stocking for six grazing cycles in spring and summer

Herbage Mass, Forage Accumulation and Nutritive Value of \u3cem\u3eBrachiaria decumbens\u3c/em\u3e in a Silvopastoral System

The use of silvopastoral systems has been suggested to ensure sustainability in animal production systems because of their potential to increase soil fertility, improve forage quality, promote animal thermal comfort and provide income diversification for the producer (Paciullo et al. 2011). Nevertheless, the shade provided by trees may affect plant growth and nutritive value of forage (Sousa et al. 2010). This study aimed to assess the impact of shading on the allocation pattern of dry matter and on herbage nutritive value, under various shading regimes, in a silvopastoral system, during both the dry and rainy seasons

Evaluation of New Dwarf Elephant Grass Genotypes for Grazing

Elephant grass stands out for its production potential, forage quality and acceptance by animals. However, its tall size makes management under grazing difficult and dwarf cultivars have been selected and evaluated to overcome this limitation. The objective was to characterize agronomic aspects of dwarf elephant grass genotypes submitted to two defoliation intensities. The experiment was installed in a 5 x 2 factorial scheme, with five elephant grass genotypes (2022, 1810, 2111, 2035, BRS Kurumi) and two residue heights after defoliation (25 and 45 cm). A randomized block design with three replications in 4x3m plots was used. Forage above the residue height was cut whenever the canopy reached 93-95% light interception. Residue heights did not influence leaf/stem ratio, basal and total tillering, and dry matter production. On the other hand, influence of residue height on canopy height, aerial tillering and forage accumulation rate was observed. The forage accumulation rate increased by 19% for the 45 cm residue compared to the 25 cm residue. No interaction was observed between genotype and residue height for the variables canopy height, leaf:stem ratio, basal tillering, aerial tillering, forage mass and forage accumulation rate. In relation to tillering, BRS kurumi showed greater total and aerial tiller number, 31% higher than the average of the other materials. Although the cultivar BRS kurumi has more vigorous tillering, the variables leaf:stem ratio and forage accumulation rate were higher in the new materials, especially material 1810, which presented better performance compared to the control. In view of this, it is concluded that the new grass genotypes have a higher proportion of leaves and forage accumulation rate than BRS Kurumi, and that the residue height of 45 cm provides a higher forage accumulation rate