Effects of Guanidinoacetic Acid on Ruminal Fermentation and Greenhouse Gas Production Using Fresh Forage and Silage from Different Maize (Zea mays L.) Genotypes

Guanidinoacetic acid (GAA) is a feed additive that promotes growth in animals, while maize (Zea mays L.) used for the mitigation of ruminal greenhouse gases. However, it unknown if GAA affects efficiency mitigating gases or there synergy between them. Therefore, objective this study was to evaluate vitro production total gas, methane (CH4), carbon monoxide (CO), and hydrogen sulfide (H2S), fermentation characteristics, CH4 conversion fresh forage silage different genotypes (Amarillo, Montesa, Olotillo, Tampiqueño, Tuxpeño) maize, with without addition GAA. The Amarillo genotype AAG had highest (p = 0.01) gas rate lowest 0.044) delay time before production. In addition, at 48 h, increased 0.0001) CH4, as well proportion (mL 100 mL−1 gas). Tuxpeño produced more 0.033) CO first 24 h incubation, only 0.001) 6 h. 0.02) H2S observed ensiled Regarding Montesa presented degradation dry matter (DMD), short-chain fatty acids (SCFA), metabolizable energy (ME), although no effect on efficiency, Olotillo SCFA, ME, OM per unit CH4. It can be concluded rumen production, are influenced by condition than guanidinoacetic acid, evaluated, from showed best characteristics