Intake and Selection of Goats Grazing Heterogeneous Vegetation: Effect of Gastrointestinal Nematodes and Condensed Tannins

Small Ruminant Production Based on Rangelands to Optimize Animal Nutrition and Health: Building an Interdisciplinary Approach to Evaluate Nutraceutical Plants

“…Assessment was performed in a 200 m 2 (10 × 20 m) exclusion quadrant each site, where all the edible material was collected, identified and dried to quantify the biomass. In a second study, Torres-Fajardo et al [ 130 ] employed thirty exclusion quadrants previously identified by Global Positioning System (2 × 2 m each) and collected all the edible material which were processed in the same way as the previous experiment. Salient results in the first experiment indicate that three plant species represented the 87.9% of availability in site A, while five plants accounted for 90.2% of availability in site B.…”

“…The hepatotoxic effect of this plant had been acquired from the cattle literature, and then extrapolated to small ruminants. However, Criollo goats readily consume patches of L. camara in the LDF, specially at the end of the rainy season [ 130 ] without evident negative side-effects. More recent reviews have highlighted the proteinic value of this plant for browsing ruminants [ 134 ].…”

“…In the same way as the nutritional approach, it is expected that candidate plants do not have too much PSC/CT. This criterion could serve as an initial, but not as a definitive guide, as there are some plant species of the LDF (i.e., Neomillspaughia emarginata or Gymnopodium floribundum ) with a high concentration of CT (37.5 and 33.8%, respectively) that can make a large contribution to the diets of browsing sheep and goats [ 46 , 129 , 130 ]. Considering the latter, we want to emphasize two issues when targeting nutraceutical resources: (i) the relevance of identifying those readily consumed by animals as a first approximation (ethological approach); (ii) the fact that the quantity as well as quality of PSC are factors to consider in their bioactivity, and hence in their nutraceutical potential.…”

“…It is worth mentioning that selection can be assessed under controlled cafeteria trials by using specific selection indexes and ensuring a constant supply of the feed resources [ 183 , 184 ]. An estimation of selectivity has been performed under natural [ 129 , 130 ] and controlled [ 185 , 186 , 187 ] conditions in the LDF and other ecosystems [ 105 , 106 , 186 , 187 ].…”

“… [ 129 ] Used a single exclusion quadrant of 200 m 2 (20 × 10 m), [ 130 ] Used 30 exclusion quadrants (2 m × 2 m), <0.1 Corresponds to those plant species whose availability in the field was less than 0.1% of the total biomass availability. …”