Dietary supplementation improves animal performance and reduces methane emission intensity in young llamas grazing natural forages

The aim of this study was to evaluate the effects of concentrate supplementation on animal performance, enteric methane (CH4) emissions, and forestomach (C1-C2 and C3) fermentative parameters of young llamas grazing on natural forage. Eighteen male llamas were assigned to two treatments, with 9 animals per treatment. The treatments were forage (F) with free access to natural grassland primarily composed of Festuca spp., and F plus supplement (FS). Supplementation with ground corn and soybean expeller (80:20 ratio on DM basis) was 1.5 % based on body weight for 35 days. The total dry matter intake (DMI), CH4 emissions (g/d), and CH4 yield (g/kg DMI) did not differ between diets. However, CH4 intensity (g/kg average daily gain) was significantly reduced (-48 %) in FS than in the F diet. The pH, total volatile fatty acids, and ammonia nitrogen concentrations in the C1-C2 did not differ between diets. However, the proportion of acetate and the acetate to propionate ratio decreased but propionate and butyrate were increased in the FS than in the F diet (P < 0.05). Whereas in C3, only butyrate increased in the FS diet than in the F diet (P < 0.05). Total bacteria and methanogen populations did not differ between treatments. Nevertheless, in C1-C2 and C3, the abundance of protozoa did differ statistically (P = 0.041 and P = 0.046, respectively), in the FS diet than in the F diet. In conclusion, concentrate supplementation increased propionate and butyrate proportions of forestomach contents which lead to improve animal performance and reduced CH4 emission intensity.

Instituto de Patobiología

Fil: Ceron Cucchi, Maria Esperanza. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patobiología Veterinaria; Argentina

Fil: Ceron Cucchi, Maria Esperanza. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Fil: Ceron Cucchi, Maria Esperanza. Universidad Tecnológica Nacional. Unidad de Investigación y Desarrollo de las Ingenierías; Argentina

Fil: Gere, José. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Fil: Gere, José. Universidad Tecnológica Nacional. División Investigación y Desarrollo de Ingenierías; Argentina

Fil: Chavarria, Nicolás José. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Abra Pampa; Argentina

Fil: Ramos, Nadia Elizabeth. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Abra Pampa; Argentina

Fil: Takahashi, Lumena S. University of Sao Paulo. Centre for Nuclear Energy in Agriculture. Laboratory of Animal Nutrition; Brasil

Fil: Montiel, María Delfina. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; Argentina

Fil: Acuña, Francisco. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Abra Pampa; Argentina

Fil: Ortiz Chura, Abimael. Institut National de Recherche pour l'agriculture, l'alimentation et l'environnement (INRAE). Université Clermont Auvergne; Francia

Fil: Cravero, Silvio Lorenzo Pedro. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina

Fil: Cravero, Silvio Lorenzo Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina