92 Rearing system influenced the performance, GI-parasite burden, and immune profile of pregnant does during winter

Abstract

Abstract Small ruminants in the Southeast are predominantly raised outdoors, regardless of seasons and associated weather conditions. Severe weather in winter can decline the performance of pregnant animals and compromise their performance and immunological states. Indoor raising of pregnant animals during winter may minimize the adverse effect of cold stress; however, such potential has not been evaluated. This study hypothesized that performance, GI-parasite burden, and immune response would differ between pregnant does raised outdoor and indoor during winter. The objective of this study was to evaluate the performance, GI-parasite burden, and hematological, biochemical, and immunological parameters of pregnant does raised outdoor and indoor in winter. The study was conducted from late January to early April 2023. Sixteen pregnant Kiko does were divided into outdoor and indoor groups. Outdoor group was kept in one grazing plot consisting of mobile shelters, mineral feeders, hay feeders, and watering troughs. Indoor group was kept in individual pens consisting of containers for water, minerals, hay, and grain. Both groups were given corn and soybean mixed in 3:2 ratio (0.8% of animal body weight), ad libitum hay, minerals, and water. Daily ambient temperature and relative humidity (RH) data were collected for both sites, and temperature-humidity index (THI) was calculated. Animal performance data [body weight, body condition score (BCS), and FAMACHA score] and fecal samples were collected on d 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. Blood samples were collected on d 1, 34, and 69 and analyzed for hematological, biochemical, and immunological parameters. Data on weather, animal performance, and hematological, biochemical, and immunological parameters were analyzed using the GLM procedure and EPG data were analyzed using the Wilcoxon Rank-Sum test in SAS 9.4. Indoor temperature was higher (7%, P < 0.01), RH was lower (8%, P < 0.05), and THI was higher (5%, P < 0.01) vs. outdoor. Overall, indoor does had better FAMACHA by 9% (P < 0.05) and greater EPG by 35% (P < 0.05). Eosinophils were reduced by 73% (P < 0.05), calcium was increased by 11% (P < 0.01), and total bilirubin was greater by 86% (P < 0.05) in indoor does at the end of the study (P < 0.05) vs. outdoor does. Results showed that performance, GI-parasite burden, and biochemical and immunological parameters of pregnant does were influenced by the rearing system during winter.