【摘要】 本研究旨在通过监测规模化养殖场多胎与单胎妊娠肉用绵羊在妊娠后期不同时间点的血酮(β-羟基丁酸，BHBA)水平，确定妊娠毒血症的适宜预警时机，并评估不同预防与治疗措施的效果，为制定肉绵羊多胎妊娠后期妊娠毒血症预警与防治方案提供科学依据。试验根据母羊品种和B超妊娠胎儿数检查结果，将妊娠母羊分为多胎妊娠群240只(分为20个小圈，每圈12只)和单胎妊娠群90只(8个小圈，每圈11-12只)。每个小圈随机选取1只母羊，分别于产前60 d、50 d、35 d、20 d、10 d和5 d监测血酮。产前20 d发现有3圈单胎妊娠母羊(37.50%,3/8)和9圈多胎妊娠母羊(45.00%,9/20)的监测个体血酮值进入亚临床妊娠毒血症预警范围，另有2圈(10.00%,2/20)多胎群个体血酮值达到临床型妊娠毒血症水平。对亚临床型羊群分别实施三种预防方案(改善饲养水平、添加过瘤胃胆碱、改善饲养水平+添加过瘤胃胆碱)并与未处理组对比；10 d后(产前10 d)再次监测血酮，评估预防效果。对临床型病例采用丙二醇灌服联合硼葡萄糖酸钙注射及饲养改善进行治疗，疗程结束后复检血酮、评估疗效。对血酮值未达到亚临床型妊娠毒血症范围的羊群，采取改善饲养水平措施。结果显示，三种预防措施均能有效降低血酮水平，其中"改善饲养水平+添加过瘤胃胆碱"组效果最佳；未预防组中有7只(19.44%,7/36)在产前20 d至分娩期间发展为临床型病例，经治疗后有4只母羊临床症状得到缓解，3只母羊死亡。对达到临床型妊娠毒血症范围的羊群，经治疗及饲养改善后，血酮整体下降；其中4只(16.70%,4/24)在产前发展为临床型并继续治疗，最终2只死亡。血酮正常的母羊在产前改善饲养水平后，血酮水平呈现先升高后回落的趋势，且始终未突破亚临床阈值。试验工作为制定妊娠肉绵羊妊娠毒血症的预警与防治方案提供了理论依据和技术支撑。更多还原

【Abstract】 This study aimed to determine the optimal early warning period for pregnancy toxemia and evaluate the efficacy of different prevention and treatment measures by monitoring blood ketone(β-hydroxybutyrate,BHBA) levels in multiparous and uniparous meat type ewes during late gestation under intensive farming conditions.Based on breed and ultrasound confirmed litter size,pregnant ewes were divided into a multiparous group(240 ewes, housed in 20 pens of 12 each) and a uniparous group(90 ewes,housed in 8 pens of 11-12 each).One ewe per pen was randomly selected for blood BHBA monitoring at 60,50,35,20,10,and 5 days before parturition.At 20 days pre-partum,blood ketone levels entered the subclinical pregnancy toxemia warning range in 3 single litter pens(37.50%,3/8) and 9multiple-litter pens(45.00%,9/20),while clinical pregnancy toxemia was detected in 2 multiple litter pens(10.00%,2/20).Ewes with subclinical ketosis were assigned to three preventive regimens:improved feeding,rumen protected-choline supplementation,and combined improved feeding with rumen-protected choline,alongside an untreated control group.Blood BHBA was rechecked 10 days later(10 days pre-partum) to assess preventive outcomes.Clinical cases received oral propylene glycol and intravenous calcium borogluconate along with improved feeding,with post-treatment BHBA evaluation.Ewes with normal BHBA received improved feeding only.Results showed that all three preventive measures effectively reduced blood ketone levels,with the combined "improved feeding+rumen-protected choline" regimen performing best.In the untreated control group,7 ewes(19.44%,7/36) progressed to clinical pregnancy toxemia between 20 days pre-partum and parturition;after treatment,4 recovered and 3 died.Among ewes with clinical ketosis,blood ketone levels decreased overall following treatment and nutritional improvement;however,4 ewes(16.70%,4/24) required continued treatment due to clinical recurrence,with 2 eventual deaths.In ewes with normal initial BHBA,improved feeding induced an initial rise followed by a decline in peripheral blood ketone concentrations,which remained below the subclinical threshold throughout.This study provides a scientific basis and technical support for establishing an integrated early-warning and management protocol for pregnancy toxemia in multiparous meat-type ewes during late gestation.更多还原