Hepatic metabolomics and transcriptomics to study susceptibility to ketosis in response to prepartal nutritional management

Background:Ketosis in dairy cows is associated with body fat mobilization during the peripartal period.Sub-clinical and clinical ketosis arise more frequently in cows that are overfed energy during the entire dry(last 50 to 45 days prior to parturition)or close-up period(last^28 days prepartum).Methods:A retrospective analysis was performed on 12 cows from a larger cohort that were fed a higher-energy diet[1.54 Mcal/kg of dry matter(DM);35.9%of DM corn silage and 13%of DM ground corn]during the close-up dry period,of which 6 did not develop clinical ketosis(OVE,0.83 mmol/L plasma hydroxybutyrate;BHB)and 6 were diagnosed with clinical ketosis(KET,1.4 mmol/L BHB)during the first week postpartum.A whole-transcriptome bovine microarray(Agilent Technologies)and metabolomics(GC-MS,LC-MS;Metabolon~?Inc.)were used to perform transcript and metabolite profiling of liver tissue harvested at-10 days relative to parturition which allowed to establish potential associations between prepartal transcriptome/metabolome profiles and susceptibility to clinical ketosis postpartum.Results:Cows in KET had greater(P=0.01)overall body weight between-2 and 1 week around parturition,but similar body condition score than OVE.Although dry matter intake(DMI)did not differ prepartum,KET cows had lower(P<0.01)DMI and similar milk yield as OVE cows during the first week postpartum.Transcriptome analysis revealed a total of 3065 differentially expressed genes(DEG;P≤0.05)in KET.Metabolomics identified 15 out of 313 total biochemical compounds significantly affected(P≤0.10)in KET.Among those,greater concentrations(P≤0.06,+2.3-fold)of glycochenodeoxycholate in KET cows also have been detected in humans developing non-alcoholic fatty liver disease.Bioinformatics analysis using the Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway database and the DEG revealed that,among the top 20 most-impacted metabolic pathway categories in KET,65%were overall downregulated.Those included’Metabolism of cofactors and vitamins’,’Biosynthesis of other secondary metabolites’,’Lipid’,’Carbohydrate’,and’Glycan biosynthesis and metabolism’.The lower relative concentration of glucose-6-phosphate and marked downregulation of fructose-1,6-bisphosphatase 2 and pyruvate dehydrogenase kinase 4 support a strong impairment in gluconeogenesis in prepartal liver of cows developing KET postpartum.Among the top 20 most-impacted non-metabolic pathways,85%were downregulated.Pathways such as’mTOR signalling’and’Insulin signalling’were among those.’Ribosome’,’Nucleotide excision repair’,and’Adherens junctions’were the only upregulated pathways in cows with KET.Conclusions:The combined data analyses revealed more extensive alterations of the prepartal liver transcriptome than metabolome in cows overfed energy and developing ketosis postpartum.The causative link between these tissue-level adaptations and onset of clinical ketosis needs to be studied further.

Ketosis-prone diabetes mellitus:A phenotype that hospitalists need to understand

Diabetes has been classified mainly into types 1 and 2.Some type 2 diabetes patients,when developing ketosis,have been labeled as having atypical diabetes.Lately,syndromes of ketosis-prone diabetes,primarily in patients who we previously classified as type 2 diabetics,have emerged,and calls are being made to even reclassify diabetes.This mini-review will extensively deal with the historical,molecular,phenotypical,and clinical basis of why ketosis-prone diabetes is different than the traditional principles of type 1 and 2 diabetes and should be classified as such.Clinicians,especially those who are not diabetologists or endocrinologists,as well as hospitalists,intensivists,and primary care providers,will greatly benefit from this review.

Trends of Kalemia at Diagnosis of Acidosis versus Non-Acidosis Diabetic Ketosis Décompensations in Ouagadougou (Burkina Faso)

Introduction: Electrolyte’s profile in non-acidosis diabetic ketosis is poorly specified. We aimed to determine the nature of diabetic ketosis decompensations as well as the profile of kalemia and factors associated with its disorders at diagnosis of acidosis compared to non-acidosis diabetic ketosis. Methods: The study was retrospective from 1 January 2010 to 31 December 2011 in Yalgado Ouédraogo teaching hospital. Diabetic in-patients suffering from simple ketosis, keto-acidosis or mixed decompensation, who achieved blood electrolytes assessment before intensive insulin therapy were included. Results: Sixty two patients were studied. The sex ratio was 0.7 and the mean age was 41.7 years. Keto-acidosis, simple ketosis and mixed decompensation were diagnosed respectively in 18 (29%), 32 (51.6%) and 12 (19.4%) patients. Kalemia was normal in 42 (67.7%), while hypokalemia and hyperkalemia were reported respectively in 11 (17.8%) and 9 (14.5%) patients. Kalemia was often normal in all types of ketosis decompensation and disorders of kalemia occurred more in patients with keto-acidosis (50%) than those with simple ketosis (21.9%);p = 0.04. Renal failure was diagnosed in 10 patients (50%) with and 2 (4.8%) without kalemia’s disorders;p = 0.0001. Seven patients (35%) with and 4 (9.5%) without kalemia’s disorders suffered from unconsciousness;p = 0.02. It happens more in hyperkalemia (44.4%) than in normal kalemia condition (9.5%);p = 0.02. Conclusion: If kalemia is often normal in all types of diabetic ketosis emergencies, hypokalemia is the most initial frequent potassium disorder.

The effects of nutritional ketosis induced by Bigu-herbs regimen and ketogenic diet on diseases and aging

The Bigu-herbs regimen,a Taoism(Taoism is an ancient Chinese Taoist philosophy system)special health-preserving technique to achieve longevity through strict abstinence from food,limits the intake of grains and uses herbs to replace normal diet to gain energy.Practicing Bigu-herbs regimen for several weeks to several years can make one lose weight,prevent diseases,and prolong life.The modern ketogenic diet(KD)mainly limits carbohydrate intake and increase fat intake.The low-carbohydrate,high-fat,and adequate protein diet is well known for its antiepileptic and neurotrophic effects.Limiting the intake of carbohydrate results in energy metabolism reprogramming to mobilize the steatolysis,energize and promote ketone bodies(KBs)production,achieving a state of nutritional ketosis(NK).The researchers summarized how ketone bodies or NK affects diseases and the aging process,as well as the side effects of KD.NK has a favorable effect on caloric intake,lipid parameters,glycemic index,and insulin sensitivity;moreover,it can be used as a treatment option for diabetes,obesity,and other metabolic disorders.NK is recognized as being neuroprotective and is good for epilepsy,Alzheimer’s disease,and emotional disturbance.Targeting the metabolic differences between tumor and normal cells,NK limits the use of glucose and impairs energy metabolism in cancer cells,inhibiting their growth and rendering them susceptible to clinical treatments.NK also affects inflammation and the release of cytokines,regulate gut flora,extend longevity and health span,and preserve physiologic functions.The side effects of KDs are controllable under the guidance of a specially trained dietitian and medical team.

Combination of nutritional ketosis and hyperoxygenation therapy-promising ground for integrative cancer treatment: a systematic review

Though the cancer is a multifactorial disease,where various types of cancers exhibit varying mechanisms,pathways,genetic and cellular defects,the study of tumor micro-environment confirms that upregulated glycolysis and hypoxia are the part and parcel of almost every cancer subtypes.Therefore,targeting them with nutritional ketosis and hyper-oxygenation therapies could create an unfavourable environment for cancers to thrive.The aim of this review is to study the significance of these interventions in the integrative cancer treatment.Extensive search has been carried out through the online scientific database like PubMed and other medical journals with the search words,‘cancer metabolism’,‘tumor micro environment’,‘hypoxia and tumor’,‘ketosis and cancer treatment’,‘hyperbaric oxygen therapy and cancer’and‘ozone therapy and cancer’.All biomolecule studies,preclinical and clinical studies,received as search results are reviewed.In addition,a nutritional book,named‘Healing with Whole Foods:Asian Traditions and Modern Nutrition’by Paul Pitchford is also referred.These studies recommend the use of various therapeutic approaches like ketogenic diet,ketone supplementation,hyperbaric oxygen therapy and intravenous ozone therapy,individually or in combination with standard therapies,based on its antitumor effects,safety,tolerability,its ability to potentiate the radio and chemo therapy,while decreasing its side effects and its efficiency to improve the quality of life.Rewardingly,when combined,the synergistic action of nutritional ketosis and hyperoxygenation therapies elicited profound,supra additive anti-cancer effects.As per present studies,these therapies are safe to include in an Integrative cancer treatment,though large clinical trials are needed to systematize its clinical usage.

Diabetic Ketosis Decompensations at the National Hospital in Benin (West Africa), What Did We Learn about the Precipitating Factors?

We performed a retrospective study on diabetic ketosis decompensations in 101 diabetic patients in Endocrinology and Metabolic Diseases Service of the National Hospital and Universitary Koutoukou Hubert Maga (CNHU-HKM) for a period of 3 years. Objective: The main objective of the study was to identify the underlying factors of ketosis decompensations for a more focused education program. Results: The mean age was 43.84 years. In half of cases (49.5%), the ketosis decompensations were inaugural for the diabetes. Type 2 diabetes was predominant with a frequency of 85.1% versus 14.9% for type 1 diabetes. The overall prevalence rate of ketosis decompensations was 21.82%. The precipitating factors were infections (51.49%) and treatment withdrawal (25.74%). The average blood glucose was 4.46 g/L with ranges of 1.86 g/L and 13 g/L. The outcome was favorable in 89.1% of cases. The mortality rate was 7.9%. The average hospital stay was 13.23 days. Conclusion: This study showed that ketosis decompensations are still frequent. The main precipitating factors are infection and therapeutic noncompliance. Preventive actions are needed through screening programs, regular monitoring and targeted education.

奶牛酮病早期预警技术的研究进展

近年来,奶牛养殖业进入快速发展时期,而养殖高成本、高发病率和低产出是阻碍奶牛养殖业持续发展的障碍。其中,奶牛酮病的发病率有逐年升高趋势,不同的胎次、产后天数、月份、泌乳量等风险因素均影响奶牛酮病的发生。目前,基于奶牛行为、奶牛生产性能测定数据、代谢组学技术和机器学习的酮病早期预警技术已经取得巨大进展。本文综述了奶牛酮病的发病规律和酮病早期预警技术,为奶牛围产期健康管理提供理论参考,对促进奶业提质增效、提高奶牛福利具有重要意义。

新型补钙剂对奶牛产后低血钙症和酮病的防治作用

本试验旨在研究新型补钙剂对奶牛产后低血钙症和酮病的防治作用。选取60头健康经产的荷斯坦围产期奶牛,随机分为2组,每组30头牛,其中2胎和3胎及3胎以上胎次奶牛各15头。试验组奶牛产犊时投服新型补钙剂,对照组奶牛投服常用补钙剂;2胎奶牛产犊时投服1管/头,3胎及3胎以上胎次奶牛产犊后12 h再投服1管/头。投服补钙剂后1、4、8 h采集尾根静脉血样,3胎及3胎以上胎次奶牛在投服补钙剂后12、16、20 h继续采集尾根静脉血样。测定血液矿物元素含量、血气指标、血液生化指标,并记录产后7 d内的平均产奶量和产后21 d内代谢性疾病发生率。结果表明:1)投服2种补钙剂后,所有奶牛产后1~8 h血液离子钙(iCa)含量均呈上升趋势,其中试验组3胎及3胎以上胎次奶牛产后8~20 h时血液iCa含量显著高于产后1 h(P<0.05)。试验组所有奶牛产后8 h血液镁离子(Mg^(2+))含量显著高于对照组(P<0.05)。2)对照组2胎奶牛产后8 h血液剩余碱(BE)含量显著高于试验组(P<0.05)。试验组3胎及3胎以上胎次奶牛产后8~20 h血液碳酸氢根(HCO-3)含量显著高于产后1 h(P<0.05),对照组产后4、8和20 h血液HCO-3含量显著高于产后1 h(P<0.05)。3)对照组2胎奶牛血液非酯化脂肪酸(NEFA)含量随时间增加显著降低(P<0.05),2组3胎及3胎以上胎次奶牛产后4~20 h血液NEFA含量显著高于产后1 h(P<0.05)。试验组2胎奶牛产后1、4和8 h血液谷氨酰转肽酶(GGT)活性显著低于对照组(P<0.05),试验组3胎及3胎以上胎次奶牛产后4~20 h血液GGT活性显著低于产后1 h(P<0.05)。4)试验组2胎牛平均产奶量显著高于对照组(P<0.05),试验组奶牛产后酮病发病率显著低于对照组(P<0.05)。综上所述,不同胎次奶牛投服新型补钙剂有利于产后低血钙症和酮病的预防,降低奶牛产后酮病发病率,减少产犊应激对奶牛生产性能的影响。

围产期奶牛酮病的发病机制和预警标志物研究进展

奶牛酮病是围产期最常见的营养代谢病之一,患酮病的奶牛产奶量和繁殖性能下降,且易继发各种疾病,增加了治疗成本,给养殖业造成了巨大的经济损失,严重阻碍了奶牛业的健康发展。早期诊断和预测酮病的发生是防控的关键环节。目前,基于酮病相关的血液、牛乳、尿液、瘤胃液、生理活动、生产管理数据等构建了奶牛酮病预测模型。本文围绕奶牛酮病的发病机制及早期诊断和预测研究进行了综述,以期为健全奶牛酮病风险预警体系提供理论依据。

奶牛酮病诊断方法及防治措施

奶牛酮病是影响畜牧业发展的代谢疾病之一。高产奶牛易患酮症,会对奶牛的健康、生育能力和产奶量产生影响。奶牛酮病的发生受遗传和营养因素的影响,培育健壮、抗病能力强的奶牛是养殖场的工作目标。论文从奶牛酮病的分类、国内外发病率及其对牧场生产的危害,综述了奶牛酮病的诊断方法及其防治措施,以期为牧场保障奶牛健康,提高奶牛生产能力做参考。

酮病奶牛血清脂代谢和肝功能相关指标的变化

奶牛酮病是常见的由碳水化合物和脂肪代谢紊乱引起的一种群发性代谢病,该病主要以酮血症、酮尿症和酮乳症为特征。为探究产后酮病患牛血液生化指标的变化,本试验选取宁夏回族自治区银川市某奶牛养殖场24头体况和产后时间间隔相近的荷斯坦奶牛进行血液生化指标检测,根据全血中β-羟丁酸(BHBA)浓度将被检奶牛分为酮病组和对照组进行比较研究。结果显示,与对照组奶牛相比,酮病组奶牛乳酸脱氢酶(LDH)、天门冬氨酸氨基转移酶(AST)和碱性磷酸酶(ALP)的含量极显著升高(P<0.01);谷氨酰转肽酶(GGT)和总胆红素(T-bil)的含量显著升高(P<0.05);低密度脂蛋白(LDL)、甘油三酯(TG)和葡萄糖(Glu)含量极显著降低(P<0.01);钙(Ca)、磷(P)、尿素(UREA)和肌酐(Crea)含量无显著性差异(P>0.05),但前三者均低于正常参考范围,而Crea含量稍高于正常参考范围,即机体伴有低血钙、低血磷和肾功能机能障碍。结果表明,在奶牛酮病发生过程中伴随着脂代谢紊乱和肝功能损伤,本试验结果可为奶牛酮病的防治提供理论依据。

不同瘤胃保护性胆碱对围产后期奶牛酮病发病率和血液代谢指标的影响

本试验通过尼龙袋降解试验和饲喂试验,比较两种过瘤胃胆碱的干物质降解率和胆碱保护率及其对围产期奶牛酮病发病率和血液代谢指标的影响。研究分为两个部分:试验一使用尼龙袋法在瘤胃瘘管奶牛上对两种过瘤胃胆碱(A为对照组,B为试验组)的干物质降解率和胆碱保护率进行测定。试验二选取广西某规模化奶牛场的围产牛,采用分阶段对比试验设计,于产前21d开始至分娩分别饲喂含过瘤胃氯化胆碱A和过瘤胃氯化胆碱B的日粮;试验期间全混合日粮(TMR)配方保持不变。试验结果表明:与对照组相比,试验组胆碱的瘤胃干物质降解率较低,过瘤胃保护率较高。试验组奶牛酮病发病率较低;在产后14d和21d,试验组奶牛血液葡萄糖浓度显著增加。综上,根据瘤胃保护率、奶牛酮病发病率和血液代谢试验结果可知,试验组过瘤胃胆碱优于对照组。

规模化奶牛场常发高害疾病的流行病学调查与思考

2018年10月~2022年7月期间,为掌握新疆生产建设兵团第八师石河子市规模化牛场奶牛常发高害疾病的发生情况,课题组对某大型国有公司所属的6个规模化奶牛场临床发病病种及发病情况进行了不间断的流行病学调查。共调查各生长阶段的奶牛9541头,临床常发高害疾病主要有犊牛腹泻、犊牛支气管肺炎、蹄病、乳房炎、酮病、酸中毒、产科病(子宫内膜炎、胎衣不下、卵巢疾患)等,年总平均发病率为7.85%;其中:犊牛腹泻发病率最高,平均发病率为19.10%;其次是成母牛蹄病,平均发病率为15.05%;再次是酮病,平均发病率为5.76%;产科疾病发病率最低,平均发病率为2.11%。从营养平衡、气候环境和防治能力等方面探寻了致病的主要原因,以期为降低疾病造成的危害、助力石河子市奶牛业高质量发展提供技术支撑。

奶牛酮病的致病机制和诊断方法研究进展

奶牛酮病作为我国奶牛养殖业面临的重大挑战,其高发率对养殖业的稳定发展构成威胁。本文详细阐述了奶牛酮病的分类、危害、临床症状以及发病原因,同时对诊断技术进行了深入探讨。奶牛酮病根据β-羟基丁酸水平分为亚临床型和临床型。酮病对奶牛健康、产奶量、牛奶质量和繁殖性能造成严重影响,增加了牧场运营成本和风险。其发病原因多样,包括能量代谢不平衡、围产期疾病、食源性因素、饥饿状态以及特定营养素缺乏等,与糖、脂、蛋白质代谢紊乱及激素调节密切相关。在诊断方面,文章介绍了定性检测(酮粉法、试剂法、试纸条法)和定量检测(水杨醛比色法、分光光度法、气相色谱法)等多种方法。本研究为奶牛酮病的有效防控提供了全面的知识基础和技术指导,有助于提升奶牛养殖业的健康管理与可持续发展。

中药复方制剂治疗奶牛酮病的效果分析

[目的]研究中药复方制剂治疗奶牛酮病的效果,为奶牛高效养殖提供理论依据。[方法]于某养殖场中筛选90头酮病奶牛,随机分为3组,分别为西药组(氯化钙、葡萄糖、碳酸氢钠、辅酶A和地塞米松)、中药复方制剂组(加味清肝散)和中西药结合组,每组各30头,对比治疗前后病牛血酮值、治愈率、生产性能和1年内并发症发生率。[结果]治疗后3组病牛血酮值均有所下降,中西药结合组降低最显著,治愈率最高;中西药结合组奶牛生产性能显著优于西药组和中药复方制剂组;中西药结合组治愈后1年内并发症发生率明显低于西药组和中药复方制剂组。[结论]相比单一西药或中药治疗奶牛酮病,中西药结合治疗效果更佳,可降低血酮水平,提高生产性能,减少酮病对奶牛生长和生产造成的影响。

奶牛酮病与胃肠道环境间的相互影响及营养调控

酮病作为一种奶牛围产期易发的营养代谢疾病,导致其生产性能急剧下降,严重损害牧场经济效益。在消化过程中,健康胃肠道环境发挥至关重要的作用。目前研究表明,患有酮病的牛只胃肠道环境,包括胃肠道形态结构、菌群组成及瘤胃液组成成分等均会发生明显变化,而奶牛围产期间胃肠道环境的不同变化又会影响酮病发生概率,二者相互影响。据此,建议更加深入研究奶牛胃肠道菌群与酮病之间关系,为酮病的预防及治疗提供新思路。

钠-葡萄糖共转运蛋白2抑制剂相关酮症/酮症酸中毒的文献分析

目的研究钠-葡萄糖共转运蛋白2抑制剂(SGLT2i)致酮症/酮症酸中毒的发生规律及特点。方法收集PubMed、Science Direct、Web of Science、中国知网、万方、维普数据库纳入的SGLT2i导致酮症/酮症酸中毒的病例。分析患者性别、年龄、药品用法用量、不良反应发生时间、临床表现、糖尿病类型、诱发因素等信息。结果共纳入111例患者,其中男性53例(47.75%),女性58例(52.25%)。年龄分布在17~83岁,其中年龄30~<60岁者68例(61.26%),占比最大。酮症/酮症酸中毒的发生可分为药物直接引起和危险因素诱发,其中药物直接引起的有46例(41.44%),手术、感染、低碳水摄入等危险因素诱发的有65例(58.55%),临床症状大多为恶心、呕吐、纳差、腹痛、乏力、呼吸困难、意识模糊。结论SGLT2i导致的酮症/酮症酸中毒多为危险因素诱发,建议手术或感染情况下及时停用药物,避免突然减量/停用胰岛素,避免低碳水摄入及剧烈运动等情况发生。建议用药期间定期检测患者酮体水平,以便为临床用药提供指导。

奶牛酮病的危害及病理学变化

酮病是奶牛围产期常见的代谢性疾病之一,具有较高的发病率。酮病的危害主要表现为多胎次奶牛产奶量损失、脂蛋比改变、繁殖功能障碍和增加其他疾病的患病风险。近年来,氧化应激、系统性炎症、肝脏脂质沉积和胰岛素抵抗方面取得巨大的进展,然而关于奶牛酮病的病理学变化的报道较为缺乏。因此,本文围绕奶牛酮病的危害、酮病的病理学变化、酮病与胃肠道菌群功能的关联性研究进行综述,旨在为提高奶牛产后健康和降低酮病发病率制定新的营养调控策略提供理论参考。

奶牛亚临床酮病血液生化指标分析及糖皮质激素影响肝细胞糖异生作用分子机制的研究

为探究围产期奶牛亚临床酮病血清中生化指标的变化特征,本研究选取2~4胎次荷斯坦围产期奶牛45头,分别在分娩前7 d、分娩当天晨饲前经尾根静脉采血,以血酮检测值<1.2 mmol/L为健康组,≥1.2 mmol/L为酮病组。采用ELISA试剂盒测定分娩前7 d、分娩当天、分娩后7 d、14 d健康组和酮病组奶牛血液中的生化指标。结果显示,酮病组奶牛分娩前7 d和分娩当天血清中皮质醇含量显著高于健康组(P<0.05);并且酮病组奶牛分娩前7 d血清中β-羟丁酸(BHBA)、高密度脂蛋白(HDL-C)含量显著高于健康组(P<0.05);酮病组奶牛分娩前后血清中葡萄糖(Glu)、甘油三脂(TG)、极低密度脂蛋白(VLDL-C)、游离脂肪酸(FFA)含量较健康组虽无显著差异,但均高于健康组。分别以0、1×10^(-7)mmol/L、1×10^(-8)mmol/L、1×10^(-9)mmol/L浓度的糖皮质激素(GC)刺激原代分离培养的犊牛肝细胞,作用0、1 h、3 h、6 h、24 h后采用荧光定量PCR检测肝细胞中糖异生相关受体及其相关酶编码基因的相对转录水平,并以皮尔森相关系数对糖异生相关受体及其相关酶编码基因的转录水平进行相关性分析。q PCR结果显示:高浓度GC促进原代犊牛肝细胞中糖皮质激素受体(GR)NR3CI的转录水平,低浓度GC促进盐皮质激素受体(MR)NR3C2的转录水平。糖异生相关限速酶PC、PEPCK-C、PCK2、11β-HSD1、11β-HSD2编码基因的相对转录水平随GC浓度和其作用时间而变化。皮尔森(Pearson)相关性分析结果显示:PC、PCK2、11β-HSD1基因的相对转录水平与NR3C1极显著相关(P<0.01),PEPCK-C、11β-HSD1、11β-HSD2与NR3C2的相对转录水平显著相关(P<0.05)。上述结果表明酮病奶牛分娩前GC水平升高,而GC可能通过结合其受体GR/MR提高奶牛肝细胞中糖异生关键酶PC、PEPCK-C、PCK2、11β-HSD1和11β-HSD2编码基因m RNA的转录,从而促进糖异生作用。本研究为酮病奶牛体内糖脂代谢相关激素GC的内分泌调节作用及其分子机制和GC的临床应用奠定实验基础。

夏季高温条件下添加酵母培养物对奶牛生产性能和酮病风险的影响

本试验旨在研究夏季高温条件下添加酵母培养物对奶牛机体应激、生产性能和酮病风险的影响。选取40头处于泌乳中后期的奶牛,根据奶牛体重、泌乳天数、胎次、产奶量相近的原则,随机分配入2个组,其中对照组20头,试验组20头。对照组仅饲喂基础日粮,不添加酵母培养物;试验组为酵母培养物处理组,在基础日粮中添加15g/d的酵母培养物。试验周期为10周,其中预饲期2周,正试期8周。结果显示:①酵母培养物处理组的饲料采食量不受影响,该组奶牛产奶量和饲料效率得到提升,乳中体细胞数降低;②酵母培养物可有效降低夏季高温条件下奶牛血液中氧化应激水平和热休克蛋白的含量,从而优化奶牛的健康状态。③添加酵母培养物可降低血液中β-羟基丁酸含量,从而降低酮病发生率。本研究结果表明,日粮中添加酵母培养物能够有效改善泌乳奶牛的生产性能、机体抗氧化能力和酮病发生风险,从而为高温条件下奶牛健康养殖提供新思路。