Herbage intake by cattle in kikuyugrass pastures under intermittent stocking method

Daniel Schmitt, Deisy Andrade Padilha, Cauby de Medeiros-Neto, Henrique Mendonça Nunes Ribeiro Filho, Lynn Elwood Sollenberger, André Fischer Sbrissia

Resumo


Two complementary experiments were conducted to investigate the relationships between the canopy structure of Pennisetum clandestinum (kikuyugrass) pastures created by intermittent stocking strategies and daily herbage intake by cattle. The first experiment (Exp. I) evaluated the relationship between different pre-grazing heights (10, 15, 20, and 25 cm) and a single defoliation intensity (50% reduction in the initial heights). In the second experiment (Exp. II), four defoliation intensities (40, 50, 60, or 70% reduction in height) were combined with a single pre-grazing height (25 cm). The following variables were analyzed: i) plant-part composition, herbage mass, and bulk density of the grazing layer; and ii) daily herbage intake. The data were analyzed using orthogonal polynomial contrasts. The Tukey-Kramer test was used to compare daily herbage intake means so that the differences among treatments could be characterized. In general, herbage intake decreased as the pre-grazing canopy height decreased (Exp. I; P = 0.03) and as defoliation intensity increased (Exp. II; P = 0.02). These response patterns were associated with canopy structure, both that existing before and that created during the stocking period. In conclusion, pre-grazing heights lower than 25 cm or defoliation intensities greater than 40% reduce daily herbage intake by cattle in kikuyugrass pastures under intermittent stocking.

Palavras-chave


Grazing management; Pennisetum clandestinum; Rotational stocking; Defoliation severity

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Referências


ALLDEN, W. G.; WHITTAKER A. M. The determinants of herbage intake by grazing sheep: the interrelationship of factors influencing herbage intake and availability. Australian Journal of Agricultural Research, v. 21, n. 1, p. 755-766.

AMARAL, M. F. et al. Sward structure management for a maximum short-term intake rate in annual ryegrass. Grass and Forage Science, v. 68, n. 2, p. 271-277, 2012.

BENVENUTTI, M. et al. Foraging mechanisms and their outcomes for cattle grazing reproductive tropical swards. Applied Animal Behaviour Science, v. 113, n. 1/3, p. 15-31, 2008.

BIRCHAM, J. S.; HODGSON, J. The influence of sward condition on rates of herbage growth and senescence in mixed swards under continuous stocking management. Grass and Forage Science, v. 38, n. 4, p. 323-331, 1983.

CARVALHO, P. C. F. Harry Stobbs memorial lecture: can grazing behaviour support innovations in grassland management? Tropical Grasslands-Forrajes Tropicales, v. 1, n. 1, p. 137-155, 2013.

CONGIO, G. F. S. et al. Strategic grazing management towards sustainable intensification at tropical pasture-based dairy systems. Science of the Total Environment, v. 636, n. 1, p. 872-880, 2018.

DENNIS, T. S. et al. Effects of co-grazing dairy heifers with goats on animal performance, dry matter yield, and pasture forage composition. Jornal of Animal Science, v. 90, n. 12, p. 4467-4477, 2012.

DOBOS, R. C. et al. Grazing behaviour and pattern of intake of dairy cows grazing kikuyu (Pennisetum clandestinum) grass pastures in relation to sward height and length of grazing session. Animal Production Science, v. 49, n. 3, p. 233-238, 2009.

DOVE, H.; MAYES, R. W. Protocol for the analysis of n-alkanes and other plant-wax compounds and for their use as markers for quantifying the nutrient supply of large mammalian herbivores. Nature Protocols, v. 1, n. 4, p. 1680-1697, 2006.

FONSECA, L. et al. Management targets for maximizing the short-term herbage intake rate of cattle grazing in Sorghum bicolor. Livestock Science, v. 145, n. 1/3, p. 205-211, 2012.

GIMENES, F. M. et al. Ganho de peso e produtividade animal em capim-marandu sob pastejo rotativo e adubação nitrogenada. Pesquisa Agropecuária Brasileira, v. 46, n. 7, p. 751-759, 2011.

LACA, E. A.; UNGAR, E. D.; DEMMENT, M. W. Effects of sward height and bulk density on bite dimension of cattle grazing homogenous swards. Grass and Forage Science, v. 47, n. 1, p. 91-102, 1992.

MAYES, R. W.; LAMB, C. S.; COLGROVE, P. M. The use of dosed and herbage n-alkanes as markers for the determination of herbage intake. The Journal of Agricultural Science, v. 107, n. 1, p. 161-170, 1986.

MEZZALIRA, J. C. et al. Behavioural mechanisms of intake rate by heifers grazing swards of contrasting structures. Applied Animal Behaviour Science, v. 153, n. 1, p. 1-9, 2014.

PALHANO, A. L. et al. Características do processo de ingestão de forragem por novilhas holandesas em pastagens de capim-mombaça. Revista Brasileira de Zootecnia, v. 36, n. 4, p. 1014-1021, 2007. Suplemento.

PÉREZ-PRIETO, L. A.; DELAGARDE, R. Meta-analysis of the effect of pre-grazing pasture mass on pasture intake, milk production, and grazing behavior of dairy cows strip-grazing temperate grasslands. Journal of Dairy Science, v. 95, n. 9, p. 5317-5330, 2012.

REEVES, M. et al. A comparison of three techniques to determine the herbage intake of dairy cows grazing kikuyu (Pennisetum clandestinum) pasture. Australian Journal of Experimental Agriculture, v. 36, n. 1, p. 23-30, 1996.

RIBEIRO FILHO, H. M. N. et al. Inter-relação entre o tempo de pastejo diurno e o consumo de forragem em vacas leiteiras. Ciência Rural, v. 41, n. 11, p. 2010-2013, 2011.

ROCHA, C. H. et al. Padrões de deslocamento de bovinos em pastos de capim-quicuiu sob lotação intermitente. Arquivo Brasileiro de Medicina Veterinária e Zootecnia, v. 68, n. 6, p. 1647-1654, 2016.

SBRISSIA, A. F. et al. Defoliation strategies in pastures submitted to intermittent stocking method: underlying mechanisms buffering forage accumulation over a range of grazing heights. Crop Science, v. 58, n. 2, p. 945-954, 2018.

SILVA, S. C. da et al. Grazing behaviour, herbage intake and animal performance of beef cattle heifers on marandu palisade grass subjected to intensities of continuous stocking management. Journal of Agricultural Science, v. 151, n. 5, p. 727-739, 2013.

SILVA, S. C. da; CUNHA, W. F. Métodos indiretos para estimar a massa de forragem em pastos de Cynodon spp. Pesquisa Agropecuária Brasileira, v. 38, n. 8, p. 981-989, 2003.

SILVA, S. C. da; SBRISSIA, A. F.; PEREIRA, L. E. T. Ecophysiology of C4 forage grasses: understanding plant growth for optimising their use and management. Agriculture, v. 5, n. 3, p. 598-625, 2015.

SMIT, H. J. et al. Comparison of techniques for estimating herbage intake of grazing dairy cows. Journal of Dairy Science, v. 88, n. 5, p. 1827-1836, 2005.

SPÖRNDLY, E.; BURSTEDT, E. Effects of sward height and season on herbage intake of strip-grazed dairy cows. Acta Agricultura Scandinavica, Section A - Animal Science, v. 46, n. 2, p. 87-96, 1996.

TRINDADE, J. K. et al. Composição morfológica da forragem consumida por bovinos de corte durante o rebaixamento do capim-marandu submetido a estratégias de pastejo rotativo. Pesquisa Agropecuária Brasileira, v. 42, p. 883-890, 2007.

VOLTOLINI, T. V. et al. Características produtivas e qualitativas do capim-elefante pastejado em intervalo fixo ou variável de acordo com a interceptação da radiação fotossinteticamente ativa. Revista Brasileira de Zootecnia, v. 39, n. 5, p. 1002-1010, 2010.

ZANINI, G. D. et al. Distribuição de colmo na estrutura vertical de pastos de capim Aruana e azevém anual submetidos a pastejo intermitente por ovinos. Ciência Rural, v. 42, n. 5, p. 882-887, 2012.

ZANINI, G. D.; SANTOS, G. T.; SBRISSIA, A. F. Frequencies and intensities of defoliation in Aruana guineagrass swards: morphogenetic and structural characteristics. Revista Brasileira de Zootecnia, v. 41, n. 8, p. 1848-1857, 2012.

WEST, J. W. Effects of heat-stress on production in dairy cattle. Journal of Dairy Science, v. 86, n. 6, 2003.




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