Health and Performance of Ewes in Woodland and Silvopasture Systems[1]

The health and performance of small ruminants can be influenced by the type of vegetation available in the grazing lands, which are evolving from conventional sole pastures to other systems containing browse species, such as pastures incorporated with browse, silvopastures, and woodlands. However, how the type of grazing lands would impact animal performance and health is not documented well. The objective of this study was to determine the health and performance of ewe lambs in southern-pine silvopastures and woodlands. The study site consisted of pine silvopastures (3 plots, 0.4-ha each) planted with different cool- and warm-season forages, and woodlands (3 plots, 0.4-ha each) having numerous understory shrubs and herbaceous species. Katahdin-St. Croix-cross ewe lambs (n = 20; live weight - 29.4±1.03 kg., 5-6 months old) were rotationally stocked in study plots (10 animals/ system) from May to August 2019. Both silvopasture and woodland systems consisted of 14-year-old longleaf (Pinus palustris Mill.) and loblolly pine (Pinus taeda L.) trees. Animal performance data [live weight (LW), body condition score (BCS), FAMACHA score, and fecal egg count] were collected every 14 days and blood samples collected at the beginning and on d 80 after they were stocked in the study plots. Blood samples were analyzed for PVC using centrifuge machine and other parameters in IDEXX. Data were analyzed using the multivariate analysis of variance in SAS 9.4. The silvopasture ewes gained more weight versus the woodland ewes (P < 0.0001). Fecal egg count was correlated negatively with live weight and BCS and positively with FAMACHA score in both groups (P < 0.05). Woodland ewes showed greater levels of RBC, hemoglobin, and lymphocyte, but less blood urea nitrogen (BUN), monocyte, and basophil than silvopasture ewes (P < 0.05). Results indicate that woodland ewes may need some supplement to improve their weight gain and BUN.