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Repeated inoculation with rumen fluid accelerates the rumen bacterial transition with no benefit on production performance in postpartum Holstein dairy cows
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作者 Fanlin Kong Feiran Wang +3 位作者 Yijia Zhang Shuo Wang Wei Wang Shengli Li 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期795-811,共17页
Background The dairy cow’s postpartum period is characterized by dramatic physiological changes,therefore imposing severe challenges on the animal for maintaining health and milk output.The dynamics of the ruminal mi... Background The dairy cow’s postpartum period is characterized by dramatic physiological changes,therefore imposing severe challenges on the animal for maintaining health and milk output.The dynamics of the ruminal microbiota are also tremendous and may play a crucial role in lactation launch.We aim to investigate the potential benefits of early microbial intervention by fresh rumen microbiota transplantation(RMT)and sterile RMT in postpartum dairy cows.Twelve fistulated peak-lactation dairy cows were selected to be the donors for rumen fluid collection.Thirty postpartum cows were divided into 3 groups as the transplantation receptors respectively receiving 10 L fresh rumen fluid(FR),10 L sterile rumen fluid(SR),or 10 L saline(CON)during 3 d after calving.Results Production performance,plasma indices,plasma lipidome,ruminal microbiome,and liver transcriptome were recorded.After fresh and sterile RMT,we found that the molar proportion of propionic acid was increased on d 7 in the FR and SR groups and the bacterial composition was also significantly changed when compared with the CON group.A similarity analysis showed that the similarities between the CON group and FR or SR group on d 7 were 48.40%or 47.85%,whereas the similarities between microbiota on d 7 and 21 in the FR and SR groups were 68.34%or 66.85%.Dry matter intake and feed efficiency were not affected by treatments.Plasmaβ-hydroxybutyrate concentration in the FR group was decreased and significantly different lipids mainly included phosphatidylcholine and lysophosphatidylcholine containing polyunsaturated fatty acids.Hepatic transcriptomics analysis indicated acutephase response pathways were upregulated in the SR group.Conclusions Our study suggests that RMT can shorten the transition process of the ruminal microbiota of postpartum dairy cows with no benefit on dry matter intake or feed efficiency.Inoculation with rumen fluid may not be a useful approach to promote the recovery of postpartum dairy cows. 展开更多
关键词 Dairy cow LIPIDOMICS Liver Rumen microbiota transplantation transition period
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Empirical Research on the Factors of Chinese City Growth in the Transitional Period
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作者 LI Yingjie YANG Yongchun 《Asian Agricultural Research》 2010年第7期1-5,共5页
Based on the definition of the concept of city growth, the paper mainly discussed the factors which impact the growth of Chinese cities in the transitional period by selecting the proportion of city construction land ... Based on the definition of the concept of city growth, the paper mainly discussed the factors which impact the growth of Chinese cities in the transitional period by selecting the proportion of city construction land area to the area of the city X1(%), green coverage ratio of the built up area X2(%), the ratio of personnel involved in the secondary industry X3(%), the GDP per capita X4(×104)and other 43 indicators, by relying on the relevant data from China Urban Statistical Yearbook(2008), applying SPSS statistical software and by applying the Factor Analysis and Regression Analysis. The results show that the factors which affect the city growth have four major groups, namely economic and institutional factors, location factors, environmental factors and social cultural services and functions. Among the factors which affect Chinese city growth, the general budgetary expenditures and the general budgetary revenues of local public finance are the most important factors. The general budgetary expenditures of local finance, the general budgetary revenues, the lands of urban construction and other 12 factors obtained by gradually excluding method can be used to present the coefficient of city growth. 展开更多
关键词 transitional period City growth Chinese cities FACTORS China
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Multifaceted role of one-carbon metabolism on immunometabolic control and growth during pregnancy, lactation and the neonatal period in dairy cattle 被引量:5
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作者 Danielle N.Coleman Abdulrahman S.Alharthi +4 位作者 Yusheng Liang Matheus Gomes Lopes Vincenzo Lopreiato Mario Vailati-Riboni Juan J.Loor 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2021年第1期82-109,共28页
Dairy cattle undergo dramatic metabolic, endocrine, physiologic and immune changes during the peripartal period largely due to combined increases in energy requirements for fetal growth and development, milk productio... Dairy cattle undergo dramatic metabolic, endocrine, physiologic and immune changes during the peripartal period largely due to combined increases in energy requirements for fetal growth and development, milk production, and decreased dry matter intake. The negative nutrient balance that develops results in body fat mobilization,subsequently leading to triacylglycerol(TAG) accumulation in the liver along with reductions in liver function,immune dysfunction and a state of inflammation and oxidative stress. Mobilization of muscle and gluconeogenesis are also enhanced, while intake of vitamins and minerals is decreased, contributing to metabolic and immune dysfunction and oxidative stress. Enhancing post-ruminal supply of methyl donors is one approach that may improve immunometabolism and production synergistically in peripartal cows. At the cellular level, methyl donors(e.g. methionine, choline, betaine and folic acid) interact through one-carbon metabolism to modulate metabolism,immune responses and epigenetic events. By modulating those pathways, methyl donors may help increase the export of very low-density lipoproteins to reduce liver TAG and contribute to antioxidant synthesis to alleviate oxidative stress. Thus, altering one-carbon metabolism through methyl donor supplementation is a viable option to modulate immunometabolism during the peripartal period. This review explores available data on the regulation of one-carbon metabolism pathways in dairy cows in the context of enzyme regulation, cellular sensors and signaling mechanisms that might respond to increased dietary supply of specific methyl donors. Effects of methyl donors beyond the one-carbon metabolism pathways, including production performance, immune cell function,mechanistic target or rapamycin signaling, and fatty acid oxidation will also be highlighted. Furthermore, the effects of body condition and feeding system(total mixed ration vs. pasture) on one-carbon metabolism pathways are explored. Potential effects of methyl donor supply during the pepartum period on dairy calf growth and development also are discussed. Lastly, practical nutritional recommendations related to methyl donor metabolism during the peripartal period are presented. Nutritional management during the peripartal period is a fertile area of research, hence, underscoring the importance for developing a systems understanding of the potential immunometabolic role that dietary methyl donors play during this period to promote health and performance. 展开更多
关键词 EPIGENETICS Immune system METABOLISM Methyl donor transition period
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Effects of far-off and close-up transition cow feeding on uterine health,postpartum anestrous interval,and reproductive outcomes in pasture-based dairy cows 被引量:3
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作者 S.Meier J.K.Kay +6 位作者 B.Kuhn-Sherlock A.Heiser M.D.Mitchell M.A.Crookenden M.Vailati Riboni J.J.Loor J.R.Roche 《Journal of Animal Science and Biotechnology》 CAS CSCD 2020年第2期493-503,共11页
Background:In seasonal,pasture-based,dairy production systems,cows must recover from calving and become pregnant within two to 3 months.To achieve this,the uterus must involute and ovulation must occur and continue at... Background:In seasonal,pasture-based,dairy production systems,cows must recover from calving and become pregnant within two to 3 months.To achieve this,the uterus must involute and ovulation must occur and continue at regular intervals.As these processes are affected by the cows’nutritional or metabolic status post-calving,the objective of this study was to evaluate the effect of cow feeding strategies on uterine health,the length of postpartum anestrous interval,and reproductive outcomes.The treatments consisted of two feeding strategies during late-lactation and early dry period(far-off period;starting 4-month pre-calving)and three close-up dry period feeding regimes(1-month pre-calving)in a 2×3 factorial arrangement.We randomly assigned 150 cows to one of two far-off treatments.During late lactation,the herds(n=75 cows per herd)were either control-fed(Controlfed)or over-fed(Overfed)to achieve a low or high body condition score(4-month pre-calving;BCS;~4.25 and^4.75;10-point scale)at cessation of lactation.Within each of these treatments,three feeding levels were applied during the close-up period(1-month pre-calving):~65%(Feed65),~90%(Feed90),or^120%(Feed120)of metabolizable energy(ME)intakes relative to pre-calving requirements.Results:Uterine health improved(i.e.polymorphonucleated(PMN)cells declined)with increased feeding during the close-up period for cows in the Overfed group.The reverse was evident for the Controlfed group with the greatest PMN at the highest intakes during the close-up period.The postpartum anoestrous interval(PPAI)was shorter in cows from the Overfed group when moderately fed(Feed90)during the close-up period;in comparison,the PPAI was shorter in the Controlfed group,when those cows were overfed in the close-up period(Feed120).The cows in the Overfed treatment had greater conception and pregnancy rates if cows had moderate dry matter intakes(Feed90)during the close-up period;these reproductive variables were less under excessive feed intakes(Feed120);yet,close-up dry matter intake had little effect on conception and pregnancy rates for the Controlfed group.Conclusions:The far-off feeding strategies increased early reproductive outcomes at 3 weeks of mating.Additionally,the interaction between far-off and close-up feeding strategies resulted in high six-week pregnancy rate with a slight restriction during the close-up period but only in the far-off Overfed group.Thus,our hypothesis is supported under these conditions. 展开更多
关键词 Close-up Dairy cows Far-off Reproduction transition period
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Assessment of the Effects of Supplemental Rumen Protected B Vitamins and Choline for Periparturient Cows: A Meta-Analysis of 28 Feeding Studies
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作者 Essi Evans Emilie Fontaine +1 位作者 Ousama AlZahal Chris Gwyn 《Open Journal of Animal Sciences》 CAS 2023年第1期151-165,共15页
There are currently no prescribed requirements for B vitamins or choline for dairy cows during the transition period, but many recent studies have shown a variety of benefits from supplying these nutrients to peripart... There are currently no prescribed requirements for B vitamins or choline for dairy cows during the transition period, but many recent studies have shown a variety of benefits from supplying these nutrients to periparturient cows. The purpose of this research effort was to determine the potential benefit of including a rumen protected blend composed of B vitamins (riboflavin, folic acid, vitamin B12) and choline (RPBlend, Jefo Nutrition Inc., St. Hyacinthe, QC, Canada) for dairy cows during the transition period, based on results from 28 on-farm feeding studies (USA-12, Mexico-7, Canada-4, Chile-3, Australia-1, Brazil-1) conducted between 2011 and 2018. All farms participated in monthly herd management record keeping systems and were selected to participate in studies due to their excellent management. Meta-analyses in which risk differences were determined were used to assess the effects of the supplemental RPBlend on health parameters and reproduction. The effect size was used as the determinant of the possible contribution of RPblend on the yields of milk, energy corrected milk (ECM), fat and protein yields during the first four weeks of lactation. Results showed that the inclusion of RPblend reduced (P < 0.05) involuntary culling and mastitis by cows during the first 30 days after calving. There was a tendency (P < 0.10) for reduced retained placenta and metritis. The meta-analyses revealed that the risk of the displaced abomasum and milk fever did not diminish (P > 0.10) with the inclusion of the BPBlend. The incidence rate of subclinical ketosis, determined as blood beta hydroxy butyric acid greater than 1.2 mM was lower (P (than those not supplemented. The proportion of cows confirmed pregnant by 100 days in milk was greater for cows given the BPBlend (P < 0.05). Milk yield and ECM were greater for cows receiving the RPBlend (1.13 and 0.93 kg/cow respectively, P < 0.05). There was no change in fat yield (P > 0.10) while the yield of milk protein was greater (P < 0.05) when the cows received the blend. These results suggest that the inclusion of rumen protected B vitamins and choline can assist cow health, reproduction and production at the start of lactation. 展开更多
关键词 Lactating Dairy Cows transition period Rumen Protection B Vitamins CHOLINE
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Peripheral leukocyte and endometrium molecular biomarkers of inflammation and oxidative stress are altered in peripartal dairy cows supplemented with Zn,Mn,and Cu from amino acid complexes and Co from Co glucoheptonate 被引量:2
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作者 Fernanda Batistel Johan S.Osorio +4 位作者 Muhammad Rizwan Tariq Cong Li Jessica Caputo Michael T.Socha Juan J.Loor 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2017年第4期885-896,共12页
Background: Immune dysfunction and a higher risk of uterine infections are characteristics of the transition into lactation in dairy cows. The supply of complexed trace minerals, which are more bioavailable, could hel... Background: Immune dysfunction and a higher risk of uterine infections are characteristics of the transition into lactation in dairy cows. The supply of complexed trace minerals, which are more bioavailable, could help overcome the greater needs of these nutrients in tissues around parturition and early lactation.Results: Twenty Holstein cows received an oral bolus with a mix of inorganic trace minerals(INO) or complexed trace minerals(AAC) to achieve 75, 65, 11, and 1 ppm supplemental Zn, Mn, Cu, and Co, respectively, in the total diet dry matter from -30 d through +30 d relative to parturition. Blood for polymorphonuclear leukocyte(PMNL) isolation was collected at-30,-15, +10, and + 30 d relative to parturition, whereas endometrium biopsies were performed at +14 and +30 d. Feeding AAC led to greater PMNL expression of genes related with inflammation response(DDX58), oxidative stress response(MPO), eicosanoid metabolism(PLA2G4A and ALOX5AP), transcription regulation(PPARG), and cellular adhesion(TLN1). The upregulation by AAC in endometrium of genes related with inflammation response( TLR2, TLR4, NFKB1, TNF, IL6, IL1 B, IL10, IL8), prostaglandin synthesis(PTGS2, PTGES), and antioxidant responses(NFE2 L2, SOD1) indicated a faster remodeling of uterine tissue and potentially greater capacity to control a local bacterial invasion.Conclusions: Data indicate that trace mineral supplementation from amino acid complexes improves PMNL activity and allows the prompt recovery of uterine tissue during early lactation. As such, the benefits of complexed trace minerals extend beyond an improvement of liver function and productive performance. 展开更多
关键词 INFLAMMATION Oxidative stress Trace minerals transition period
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A Study on the Psychological Status of the Caregivers to Patients Out of ICU after Craniocerebral Tumor Surgery and Their Factors 被引量:1
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作者 Ying Li Daili Zou +3 位作者 Yu Yang Yunjia Li Qinqin Zhao Zhihuan Zhou 《Neuroscience & Medicine》 2021年第1期1-11,共11页
<div style="text-align:justify;"> <span style="font-family:Verdana;"><strong>Objective:</strong> So as to provide a theoretical basis for the future development of intervent... <div style="text-align:justify;"> <span style="font-family:Verdana;"><strong>Objective:</strong> So as to provide a theoretical basis for the future development of intervention measures to reduce the negative psychological mood of caregivers. To investigate the psychological status of the main caregivers for patients who were transferred out of ICU after craniocerebral tumor surgery and analyze their factors. <strong>Methods:</strong> 112 patients with cerebral tumor surgery were reviewed from sun yat-sen university cancer hospital. The research object is caregivers. The general data questionnaire, hospital anxiety depression scale and migration of ICU patients’ family members stress questionnaire scale investigation are collected. Multiple linear regression analysis in cerebral tumor patients with postoperative ICU transition out main factors influencing the psychological condition of the caregivers. <strong>Results:</strong> The anxiety and depression scores were (15.60 ± 5.83) and (38.73 ± 3.23) respectively. The results of multiple regression analysis showed that the gender, education level, relationship with the patient and family monthly income of the primary caregivers of the patients were the influencing factors of anxiety, depression and migration stress psychological state (P < 0.05). <strong>Conclusion:</strong> The main caregivers of patients who were transferred out of ICU after craniocerebral tumor surgery had relatively severe anxiety, depression and migration stress. Medical staff should pay attention to the psychological status of caregivers and take effective measures to promote their physical and mental health.</span> </div> 展开更多
关键词 Craniocerebral Tumor Surgery ICU transition period CAREGIVERS Psychological Status Factors Affecting
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Resilience in new nurses:a qualitative study
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作者 Lei Lyu Ling-Yan Xu +1 位作者 Min Liu Guo-Hong Li 《Frontiers of Nursing》 CAS 2020年第2期161-168,共8页
Objectives:To explore the resilience experience of new nurses and how new nurses develop and apply resilience strategies to cope with the difficulties during the transition period.Methods:A descriptive qualitative res... Objectives:To explore the resilience experience of new nurses and how new nurses develop and apply resilience strategies to cope with the difficulties during the transition period.Methods:A descriptive qualitative research method was on data acquired using data semi-structured interviews with 12 new nurses aged 20-26 years whose working time was more than 12 months but less than 24 months.Results:Analysis of the data could determine participants adopting resilience strategies to withstand difficulties and challenges in transition period.This period consisted of three main phases:"self-protection,""undertaking challenges,"and"planning future."The first-line nurse managers'feedback and flexible shift scheduling paid a vital part in promoting the resilience development of new nurses.Conclusions:Recognizing the importance of understanding and developing the resilience of new nurses in the transition period could greatly reduce the turnover rate and alleviate the shortage of nurses in global nursing workforce. 展开更多
关键词 new nurses RESILIENCE transition period qualitative study role transformation
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Conflicting Occupational Prestige Evaluations in the Transitional Period in China
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《Social Sciences in China》 2001年第3期31-44,共14页
关键词 Conflicting Occupational Prestige Evaluations in the transitional period in China
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The Science of Criminal Procedure and Its Value Theory in China's Transitional Period
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《Social Sciences in China》 1999年第4期73-80,192,共9页
关键词 The Science of Criminal Procedure and Its Value Theory in China’s transitional period
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The Basic Orientation and Goals of China's Monetary Policy During the Period of Economic Transition
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作者 杜两省 李秉祥 《Social Sciences in China》 1998年第3期42-51,192,共11页
关键词 The Basic Orientation and Goals of China’s Monetary Policy During the period of Economic transition
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Is there a great unconformity between Xiamaling and Longshan formations in the North China Craton? 被引量:1
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作者 Hongwei KUANG Nan PENG +5 位作者 Yongqing LIU Yuchong WANG Mingming CUI Xiaoshuai CHEN Dawei QIAO Keining QI 《Science China Earth Sciences》 SCIE EI CAS CSCD 2023年第5期959-984,共26页
The existence of a 0.3 Ga"great unconformity"between the Mesoproterozoic"Undefined System"Xiamaling Formation and the"Neoproterozoic"Longshan Formation has long been controversial.In this... The existence of a 0.3 Ga"great unconformity"between the Mesoproterozoic"Undefined System"Xiamaling Formation and the"Neoproterozoic"Longshan Formation has long been controversial.In this study,stratigraphy,sedimentology,detrital zircon dating,lithium isotope,and major and trace elements were applied to systematically analyze their relationship.Results demonstrate that coarse to fine sandstone-mudstone normal cycles with different grades and thicknesses exist from the Xiamaling to the Longshan formations.Sedimentary succession formed from a restricted platform with lagoon-shallow marine shelf-tidal flat-beach and tidal shoal developing in ascending order.The pebbly sandstone at the bottom of the Long shan Formation does not have the properties of basal conglomerate with tectonic significance.The youngest detrital zircon is older than 1.6 Ga for the Long shan Formation and overlying Jing'eryu Formation sandstones.In addition,no(zircon)provenance has been found from the large igneous province of 1.32-1.2 Ga in Xiamaling Formation.Theδ^(7)Li isotope values exhibit a gradually increasing trend.The Li content and CIA(Chemical index of alteration)gradually decreases from the top of the Xiamaling Formation to the lower part of the Long shan Formation.Simultaneously,as K_(2)O/Al_(2)O_(3)and FeO/Fe_(2)O_(3)decreases,Na_(2)O/Al_(2)O_(3)increases,and Li/Al,V/Cr,and V/(V+Ni)fluctuates slightly.At the boundary,the Ce/Ce^(*)and Eu/Eu^(*)show positive and negative anomalies,respectively.Further,the Rb/Sr and Al/Si values decrease,and U/Th values increase.This indicates that the geochemistry of the weathering crust at the interface of the Xiamaling Formation-Long shan Formation is not characteristic.However,it indicates a weakening of continental weathering intensity from the bottom to the top of the interface.These results do not support the existence of a large unconformity between the Xiamaling and the Longshan formations.Therefore,it is suggested that the Long shan Formation-Jing'eryu Formation should be moved to the lower level in the stratigraphic chart,where it should form part of the Mesoproterozoic"Undefined System"along with the Xiamaling Formation.On this basis,the paleogeography of the Xiamaling Formation-Longshan Formation-Jing'eryu Formation sedimentary period in the Yanliao area of North China has been reclassified. 展开更多
关键词 North China Craton MESOPROTEROZOIC transition period UNCONFORMITY Continuous sedimentation
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