NR 01. Relevancy of some ruminal measurements in cattle supplementation trials
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Jorge Combellas [1]
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[1] Universidad Central de Venezuela
Universidad Central de Venezuela
Venezuela
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- Localización: Archivos Latinoamericanos de Producción Animal, ISSN 1022-1301, ISSN-e 1022-1301, Vol. 5, Nº. 3, 1997 (Ejemplar dedicado a: Proceedings XV ALPA meeting 1)
- Idioma: inglés
- Enlaces
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Resumen
The information obtained in 11 supplementation trials with fistulated animals was used to evaluate the relevancy of the ruminal measurements carried out. The experiments were carried out with tropical roughages as the base diet and levels of supplementation varying from 0 to 40 % of total intake. The variations between extreme treatments within each trial for each measurement were calculated and used in an analysis of linear correlation and regression between them. Molar proportions of volatile fatty acids and pH varied within small ranges and no relationship was observed between their variations and consumption. Dry matter disappearance in nylon bags at 48 h (DMD) was correlated with intake (r= 0.727, P < .05), but the rate of digestion estimated as T½ had no relationship with it. Ammonia N was the measurement with the highest correlation with intake (r = 0.806, P < .01). It was concluded that only DMS and ammonia N are sufficient to complement information obtained in supplementation trials evaluating animal response. The latter measurement has the advantage that the use of rumen fistulated animals is not indispensable.
