Protein Content of Brachiaria ruziziensis (Poaceae) under the Direct and Residual Effects of Fertilization with Hen Droppings

Abstract

Aim: A study was conducted at the Research and Experimental Farm (REF) of the University of Dschang between March 2015 and December 2016, and then at the Animal Nutrition Laboratory of the Faculty of Agronomy and Agricultural Sciences. The objective of this study was to evaluate the direct and residual effects of fertilization with hen droppings on the protein content of Brachiaria ruziziensis at different phenological stages.
 Methodology: A factorial design comprising five levels of fertilization in terms of nitrogen in the form of hen droppings (0, 25, 50, 75 and 100 kg N/ha), and three phenological stages of cutting (bolting, flowering and after seed set) on 6 m2 plots (3 m x 2 m) in four replicates, i.e. a total of 60 experimental plots was used. Fertilization with hen droppings was done one month after the stump chips were grown in the first year of cultivation (direct effects). In the second year of cultivation (residual effects), no fertilization was applied. The total nitrogen content of the plant samples was determined by the Kjeldhal method and the crude protein contents were obtained by multiplying the nitrogen contents by the forage-specific coefficient of 6.25.
 Results: This study showed that protein contents obtained under the direct effect were significantly higher than those obtained under the residual effect of fertilization. Fertilization at 100 kg N/ha resulted in the highest protein contents under direct and residual fertilization.
 Conclusion: In view of the results obtained, fertilization with hen droppings at a dose of 100 kg N/ha would be recommended for the cultivation of B. ruziziensis in order to limit mineral fertilizer inputs and improve its protein content.