PSIV-29 - Performance and resiliency against gastrointestinal parasites of pregnant does and ewes raised indoor and outdoor during the winter season

Abstract: Small ruminants in the southeast USA are mostly raised on pastures (outdoor) irrespective of seasons and associated weather conditions. During the extreme weather conditions, such as that occur in winter, animals may perform better while kept indoors. However, literature is scant on the benefits of keeping animals indoors during winter. The objective of this study was to assess the performance and resiliency against gastrointestinal (GI) parasites of pregnant does and ewes raised indoor and outdoor in winter. The experiment was conducted in for 45 days from late January to mid-March 2023. Sixteen pregnant Kiko does, and eighteen pregnant Katahdin-St. Croix cross ewes were divided into two uniform groups. Group-1 animals (8 does and 9 ewes) were kept outdoor in a grazing plot that consisted of mobile shelters, mineral feeders, hay feeders, and watering troughs. Group-2 animals (8 does and 9 ewes) were kept indoor in individual pens with consisting of containers for providing water, minerals, hay, and grain. Both groups were given ad libitum hay, minerals, and water as well as corn-soybean mixed in 3:2 ratio at the rate of 0.8% of animal live weight. Ambient temperature and relative humidity (RH) were measured for both systems. Animal performance data (live weight, body condition score (BCS), and FAMACHA score) and fecal samples were collected on Day 1, weekly during the study, and at the end of the study. Fecal samples were analyzed for the type and quantity of GI parasites using the McMaster technique, and parasite eggs per gram of animal feces (EPG) was calculated. Weather data and animal performance data were analyzed using the GLM procedure and EPG data using the Wilcoxon Rank-Sum test in SAS 9.4. Temperature was higher (13.3%, p< 0.01) while RH was lower (6.25%, p< 0.01) in the indoor system. Ewes showed higher BCS (4.86%, p< 0.01) and does showed better FAMACHA score (8.5%, p< 0.01) in indoor system compared to outdoor ewes and does respectively. Haemonchus contortus was found to be the major GI parasite affecting animals kept in both systems. Indoor ewes showed higher EPG than outdoor ewes (89.8%, p< 0.05). Results suggest that indoor rearing of pregnant does and ewes during winter can enhance their performance. Further research is needed to determine the possible reasons for higher EPG in pregnant ewes raised indoor vs. outdoor.