INFLUENCIA DEL POLIETILÉN GLICOL SOBRE LOS PARÁMETROS DE PRODUCCIÓN DE GAS in vitro EN CUATRO FORRAJERAS NATIVAS CONSUMIDAS POR EL VENADO COLA BLANCA

Abstract

.mx ( ¶ Autor para correspondencia). RESUMENLa composición química y la fermentación in vitro se determinó en hojas tratadas con y sin polietilén glicol (PEG), de arbustivas nativas del noreste de México como: Acacia amentacea, Celtis pallida, Forestiera angustifolia y Parkinsonia texana colectadas en agostaderos manejados sin disturbio. Las colectas se realizaron en enero y abril de 2009 en tres municipios (China, Linares y Los Ramones) del estado de Nuevo león, México. La composición química y la cinética de la fermentación in vitro variaron ampliamente entre sitios, plantas y entre muestreos dentro de especies. Sólo A. amentacea (18 %) y P. texana (8 %), que tuvieron alto contenido de taninos condensados (TC), aumentaron significativamente los parámetros de producción de gas y la energía metabolizable (EM) después del tratamiento con PEG. Celtis pallida y F. angustifolia tuvieron el más bajo contenido de lignina (LDA) y TC; sin embargo, C. pallida resultó con la más alta fermentación in vitro. Lo anterior se podría explicar por diferencias entre arbustivas respecto a las características genéticas relacionadas con la actividad de los metabolitos secundarios de las plantas. Todas las plantas tuvieron alto valor nutricional para el venado cola blanca debido a que su aparato digestivo tiene mecanismos para neutralizar TC. ABSTRACTThe chemical composition and the in vitro fermentation in leaves, treated with or without polyethylene glycol (PEG), of native shrub from northeastern Mexico, such as: Acacia amentacea, Celtis pallida, Forestiera angustifolia and Parkinsonia texana were established. These shrubs were gathered from fields without any disturbance. Leaves were collected at two sampling times (January and April, 2009) in three municipalities (China, Linares and Los Ramones) of the state of Nuevo Leon, Mexico. A wide range in chemical composition and in vitro gas production kinetics was observed among sites, species and sampling times of each species. A. amentacea (CT = 18 %) and P. texana (8 %), which had a higher condensed tannins content (CT), significantly increased the in vitro gas production parameters and the metabolizable energy after a treatment with PEG. Celtis pallida had the highest in vitro fermentation parameters due to the lower levels of lignin (ADL) and CT. Some variation was observed among shrubs such as in F. angustifolia that had lower fermentation and lower ADL and CT. This discrepancy could be due to genotypic characteristics relative to the type of plant secondary compounds activity. All plants resulted with high nutritional value for white-tailed deer knowing that deer have digestive mechanisms to neutralize CT. PALABRAS CLAVE:Acacia amentacea, Celtis pallida, Forestiera angustifolia, Parkinsonia texana, composición quími-ca, fermentación ruminal.

Cell-Wall Composition and Digestibility of Five Native Shrubs of the Tamaulipan Thornscrub in Northeastern Mexico

“…In addition, our results indicate that, regardless of month and site, all studied species remain at satisfactory levels for ruminant nutrition, since they exceed the 7% level of CP recommended for optimal growth of microorganisms in the rumen (Yousef and Rouzbehan, 2008). Likewise, the percentage of CP for C. pallida, G. angustifolium, and F. angustifolia were higher than reported by Ramı ŕez et al (2000), Guerrero et al (2008), andDomínguez et al (2011).…”

“…The presence of PSC such as CT may explain why some species exceeded the minimum CP requirement, despite having lower digestibility (Camacho et al, 2010). On the contrary, F. angustifolia showing the lowest CP content and the lowest levels of cellulose, concomitantly it showed higher IVDMD than any other species, except for C. pallida, and also acceptable levels of metabolizable energy ranging between 6 to 9 MJ/kg of this shrub species have been reported by Domínguez-Gómez et al (2011). Therefore, it seems more than convenient that the concentration of these compounds be determined before any further animal diet testing.…”

“…(Oleaceae), Guaiacum angustifolium Engelm. (Zygophyllaceae), and Parkinsonia aculeata L. (Fabaceae), in quantities that may limit their use as fodder (Domínguez et al, 2011;Ramı ŕez et al, 2000). Also, their preference for consumption by small ruminants has been demonstrated by Ramírez et al (1997) and Foroughbakhch et al (2013).…”

Caída de hojarasca y retorno de nutrientes en diferentes comunidades vegetales del Noreste de México

“…En el noreste de México, la hojarasca de la vegetación del matorral espinoso tamaulipeco está compuesta por las hojas, ramas, estructuras reproductivas y componentes diversos (González- , González-Rodríguez et al 2019. La media anual de 5 600 kg ha −1 de hojarasca producida en la región, puede ser una alternativa de alimento para los pequeños rumiantes, en los períodos secos y durante la escasez de forraje (Domínguez-Gómez et al 2011, González-Rodríguez et al 2019.…”