Effect of polyethylene glycol 4000 supplementation on the performance of indigenous Pedi goats fed different levels of Acacia nilotica leaf meal and ad libitum Buffalo grass hay

Abstract

In a first of two experiments, twenty yearling male Pedi goats weighing 21.3 +/- 0.5 kg live weight were used in a 37-day study in a 2 (levels of PEG 4000) x 2 (levels ofAcacia) Factorial arrangement in a Completely Randomised Design to determine the effect of the level of Acacia nilotica leaf meal supplementation plus 23 g polyethylene glycol 4000 on diet intake and digestibility, and growth rate of Pedi goats fed ad libitum Buffalo grass hay. Acacia nilotica leaf meal contained high amounts of total phenolics (2.04% DM) and low amounts of condensed tannins; both extracted (0.37% DM) and unextracted (1.83% DM). Supplementation with PEG 4000 increased (P < 0.05) crude protein intake as the level of Acacia nilotica leaf meal increased from 80 to 120 g. Similarly, treatment with PEG 4000 improved (P < 0.05) DM, OM and CP digestibilities when compared to 80 g Acacia nilotica leaf meal. Supplementation with PEG 4000 resulted in an increase (P < 0.05) in blood urea concentrations. Polyethylene glycol 4000 has the potential to improve the feeding value of A. nilotica leaf meal and can, therefore, be used in the feeding systems for ruminant animals. The second experiment determined the effect of A. nilotica leaf meal supplementation on in vitro digestibility of the diets similar to the actual ratios of the first experiment. Level of A. nilotica leaf meal supplementation plus 23 g PEG 4000 supplementation improved (P < 0.05) in vitro DM, OM and CP digestibilities where 120 g A. nilotica leaf meal was supplemented. Similarly, 23 g PEG 4000 supplementation also improved (P < 0.05) in vitro CP digestibility where 80 g A. nilotica leaf meal was supplemented. In vivo DM and OM digestibilities were best predicted from in vitro DM and OM digestibilities while in vivo CP was explained by in vitro OM and CP digestibilities. It is, therefore, concluded that in vitro DM and OM digestibilities have good capacity to predict in vivo DM and OM digestibilities while OM and CP digestibilities have good capacity to predict in vivo CP digestibility.

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

“…El mejoramienindicate enhancements in nutrient availability and thus, a greater microbial activity in rumen of white-tailed deer consuming these shrubs (Rubanza et al, 2003;Motubatse et al, 2008). Moreover, the positive correlation coefficients between CT and in vitro gas production parameters and the general improvement in fermentation in A. amentacea and P. texana by adding PEG certainly reflects the deactivation of condensed tannins (Makkar, 2005;Salem et al, 2007).…”

“…Furthermore, the positive effect of PEG on in vitro gas production of A. amentacea and P. texana in the present study could PEG a especies forrajeras nativas. Los efectos positivos del PEG sobre A. amentacea o P. texana podrían indicar incrementos en la disponibilidad de nutrientes y, por tanto, una mayor actividad microbial en el rumen del venado cola blanca consumiendo estas arbustivas forrajeras (Rubanza et al, 2003;Motubatse et al, 2008). Además, las correlaciones positivas entre los TC y los parámetros de producción de gas in vitro y el mejoramiento generalizado en la fermentación de A. amentacea o P. texana debido a la adición de PEG, ciertamente refleja la desactivación de los TC (Makkar, 2005;Salem, 2005;Salem et al, 2007).…”

“…Sin embargo, las dieta del venado cola blanca en libre pastoreo, en el noreste de México, está compuesta por alrededor del 50 % de A. amentacea y 8 % P. texana (RamirezLozano, 2004), lo que podría indicar que el venado ha desarrollado mecanismos de defensa en contra de los TC. Aparentemente, el venado cola blanca tiene proteí-nas salivales con alto contenido del aminoácido prolina que interactúa con los TC contenidos en las plantas forrajeras nativas (Motubatse et al, 2008).…”

“…However, the diet of white-tailed deer in free-range, in northeastern Mexico, is composed by about 50 % of A. amentacea and 8 % P. texana (Ramirez-Lozano, 2004), which could mean that white-tailed deer has develop defense mechanisms against CT. seemingly, white-tailed deer has salivary proteins with high proline content that interacts with condensed tannins in native shrubs (Motubatse et al, 2008).…”

Blood profiles of indigenous Pedi goats fed varying levels of <i>Vachellia karroo</i> leaf meal in <i>Setaria verticillata</i> hay-based diet

“…They contribute immensely to the economy and food security of many smallholder farmers in this area (Motubatse et al, 2008). However, their productivity is constrained by shortage of good-quality feed, especially during the long dry season (Brown et al, 2016).…”