In vitro ruminal fermentation kinetic of diets containing forage cactus with urea and different starch sources

Yann dos Santos Luz, Mauro Pereira de Figueiredo, Fábio Martins Oliveira, Fernando Salgado Bernardino, Eduardo de Jesus Novaes, João Paulo Santos Roseira

Abstract


The study was conducted to evaluate fermentation kinetic of diets based on cactus forage enriched with urea and Tifton 85 hay, containing different starch sources, using semi-automated in vitro gas production technique. Treatments were disposed in a randomized block design, with four replications, where concentrates were formulated as follows: cassava roots (FSMa), semi flint corn grains (FSMiSD), dent corn grains (FSMiD) and wheat bran (FTMa). All diets were formulated to obtain 15% of crude protein. Gas pressure were measured 2, 4, 6, 8, 10, 12, 15, 18, 21, 24, 30, 36, 48, 72 and 96 h after inoculation. For fast phase maximum gas volume (Vf1), both treatments containing corn did not differ (P>0.05). FTMa differed (P<0.05) from diets composed with corn, as main starch source. Specific degradation rate of fast fraction (Kd1) was higher (P<0.05) on FSMa and FTMa diets, compared with corn diets. Colonization time (L) showed lower values (P<0.05) for FTMa diet. The lowest total gas production was observed on FTMa and the highest for FSMiD, varying from 225.49 to 268.31 mL/g, respectively. Cassava roots as starch source contributes to a faster fermentation, compared to both corns, allowing a better synchronization with faster degradation nitrogen sources.


Keywords


Carbohydrate; Ruminal degradation; Synchronization.



DOI: http://dx.doi.org/10.5433/1679-0359.2014v35n3p1501

Semina: Ciênc. Agrár.
Londrina - PR
E-ISSN 1679-0359
DOI: 10.5433/1679-0359
E-mail: semina.agrarias@uel.br
Este obra está licenciado com uma Licença Creative Commons Atribuição-NãoComercial 4.0 Internacional