S.C. Da Silva1 and P.C. de F. Carvalho2
1Universidade de São Paulo, E.S.A. “Luiz de Queiroz”, Departamento de Zootecnia, Av.
Pádua Dias, 11 – 13418-900 Piracicaba, SP, Brazil
Email: scdsilva@esalq.usp.br
2Universidade Federal do Rio Grande do Sul, Faculdade de Agronomia, Av. Bento
Gonçalves, 7712 – 91501-970 Porto Alegre, RS, Brazil
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Key points:
1. Herbage intake by animals grazing tropical/sub-tropical pastures is directly related to bite mass, as it is for those grazing temperate pastures.
2. Where these swards have low proportions of stem and dead material (controlled swards), herbage intake follows a similar pattern to that of temperate pasture species, but leaf
characteristics, such as lamina length play an important role and influence the short-term rate of intake.
3. Sward structural characteristics and behavioural factors are relatively more important than nutritional factors in terms of herbage intake regulation. The feeding value of the
herbage produced is potentially adequate to sustain high levels of beef cattle performance under controlled sward conditions, but relatively limited for dairy cows, since nutrient concentration in the forage is not optimal for high levels of daily milk yield.
4. Sward targets for attaining production objectives are now a feasible management practice on tropical pastures and should be evaluated further.
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Keywords: tropical grasslands, animal performance, grazing management
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