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Genetic Parameters for Milk,Fat Yield and Age at First Calving of Chinese Holsteins in Heilongjiang 被引量:2
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作者 Ding Ke wei,Takeo Kayaba (The United Graduate School of Agricultural Science,Iwate Uniersity,Morioka Shi,020-8550,Japan) 《Journal of Northeast Agricultural University(English Edition)》 CAS 2001年第2期105-110,共6页
Genetic parameters for milk,fat yield and age at first calving of Chinese Holsteins in Heilongjiang were evaluated using multiple trait restricted maximum likelihood procedures with an animal model.Data consisted of ... Genetic parameters for milk,fat yield and age at first calving of Chinese Holsteins in Heilongjiang were evaluated using multiple trait restricted maximum likelihood procedures with an animal model.Data consisted of records of 2496 Chinese Holsteins first lactation cows collected from 1989 to 2000.The model included 21 herd effects,four calving season effects,nine age at first calving effects,6697 animal effects.(Co)variance components of milk yield,fat yield and age at first calving were estimated with the software package for variance component estimation(VCE) by an animal model. The heritabilities were 0.14,0.21,0.38 for milk yield,fat yield and age at first calving,respectively.The estimates of genetic correlation between milk yield and fat yield,age at first calving were 0.96,-0.29,respectively.The estimate of genetic correlation between fat yield and age at first calving was -0.28. 展开更多
关键词 MILK FAT age at first calving restricted maximum likelihood animal model
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Chinese GF-1 and GF-3 satellites observed the giant iceberg calving off the Larsen C Ice Shelf 被引量:1
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作者 SHI Lijian WANG Qimao +1 位作者 ZENG Tao LIANG Chao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第11期115-115,共1页
A massive iceberg, named A-68 by National Ice Center (NIC) officially, calved away from the Larsen C Ice Shelf in Antarctica on luly 12, 2017. The iceberg A-68 is about 5 800 km2, weighs more than a trillion tons an... A massive iceberg, named A-68 by National Ice Center (NIC) officially, calved away from the Larsen C Ice Shelf in Antarctica on luly 12, 2017. The iceberg A-68 is about 5 800 km2, weighs more than a trillion tons and it is one of the biggest ever recorded icebergs. Chinese satellites Gaofen-1 (GF-1) and Gaofen-3 (GF-3) data was used to monitoring the propagation of the rift and the iceberg by National Satellite Ocean Application Service (NSOAS). 展开更多
关键词 GF SAR Chinese GF-1 and GF-3 satellites observed the giant iceberg calving off the Larsen C Ice Shelf Figure
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Association between growth rates, age at first calving and subsequent fertility, milk production and survival in Holstein-Friesian heifers 被引量:1
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作者 Jessica S. Cooke Zhangrui Cheng +1 位作者 Nicola E. Bourne D. Claire Wathes 《Open Journal of Animal Sciences》 2013年第1期1-12,共12页
Age at first calving (AFC) affects the profitability of dairy enterprises. This study examined the relationships between AFC and subsequent fertility, milk production and survival up to third calving in UK Holstein-Fr... Age at first calving (AFC) affects the profitability of dairy enterprises. This study examined the relationships between AFC and subsequent fertility, milk production and survival up to third calving in UK Holstein-Friesian heifers;Study 1 comprised 134 consecutively born heifers from the same herd (AFC 764 ± 8 days) and Study 2 contained 445 heifers born on 17 farms (AFC 796 ± 6 days). Growth rates and fertility during rearing were monitored and animals were subsequently divided into four AFC groups for analysis: <23 months, 23 - 25 months, 26 - 30 months and >30 months. The actual AFC reflected both growth rate and heifer fertility, with later calving heifers already lighter by 6 months of age. The proportion conceiving to first service was highest (93% and 84% for Studies 1 and 2, respectively) for the youngest AFC group. Fertility in the first lactation was best in cows calving at 23 - 25 months and worst in the oldest AFC group. Milk production parameters in the first and second lactations were broadly similar between AFC groups but significantly more heifers with an AFC < 26 months calved for a third time. These younger calving animals therefore achieved more days in milk over 5 years, with >44% of their days alive spent in milk production compared with only 18% - 40% in cows calving at ≥26 months. Hence cows with an AFC < 26 months produced the most milk in their first 5 years of life. These results indicate that an AFC of 0.75 kg/d up to 15 months and good heifer fertility and resulted in the best subsequent performance. 展开更多
关键词 Age at First calving HEIFER FERTILITY Milk Production LONGEVITY
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Modeling calving process of glacier with dilated polyhedral discrete element method
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作者 Lu Liu Ji Li +3 位作者 Qizhen Sun Chunhua Li Sue Cook Shunying Ji 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2021年第7期159-169,共11页
Mass loss caused by glacier calving is one of the direct contributors to global sea level rise.Reliable calving laws are required for accurate modelling of ice sheet mass balance.Both continuous and discontinuous meth... Mass loss caused by glacier calving is one of the direct contributors to global sea level rise.Reliable calving laws are required for accurate modelling of ice sheet mass balance.Both continuous and discontinuous methods have been used for glacial calving simulations.In this study,the discrete element method(DEM)based on dilated polyhedral elements is introduced to simulate the calving process of a tidewater glacier.Dilated polyhedrons can be obtained from the Minkowski sum of a sphere and a core polyhedron.These elements can be utilized to generate a continuum ice material,where the interaction force between adjacent elements is modeled by constructing bonds at the joints of the common faces.A hybrid fracture model considering fracture energy is introduced.The viscous creep behavior of glaciers on long-term scales is not considered.By applying buoyancy and gravity to the modelled glacier,DEM results show that the calving process is caused by cracks which are initialized at the top of the glacier and spread to the bottom.The results demonstrate the feasibility of using the dilated polyhedral DEM method in glacier simulations,additionally allowing the fragment size of the breaking fragments to be counted.The relationship between crack propagation and internal stress in the glacier is analyzed during calving process.Through the analysis of the Mises stress and the normal stress between the elements,it is found that geometric changes caused by the glacier calving lead to the redistribution of the stress.The tensile stress between the elements is the main influencing factor of glacier ice failure.In addition,the element shape,glacier base friction and buoyancy are studied,the results show that the glacier model based on the dilated polyhedral DEM is sensitive to the above conditions. 展开更多
关键词 glacier calving discrete element method dilated polyhedral element bond and fracture model
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Estimation of Genetic Parameters for 305 Days Milk Yields and Calving Interval in Xinjiang Brown Cattle
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作者 Xuefeng Fu Lili Lu +7 位作者 Xixia Huang Yachun Wang Kechuan Tian Xinming Xu Jiqing Fang Liming Cheng Zhiqin Guo Yuezhen Tian 《Agricultural Sciences》 2017年第1期46-55,共10页
This study was conducted to estimate variance components and genetic parameters for 305 days mature equivalent milk yields (MEM) and calving interval (CAI) of registered Xinjiang Brown cattle. The total records were 3... This study was conducted to estimate variance components and genetic parameters for 305 days mature equivalent milk yields (MEM) and calving interval (CAI) of registered Xinjiang Brown cattle. The total records were 3940 including 2579 for 305-day MEM and 1970 for CAI, which were collected from Xinjiang Urumqi Cattle Breeding farm in China with calving records from 1990 to 2008. Genetic parameters were obtained by multiple trait derivative-free restricted maximum likelihood (MTDFREML) using animal model. The model included year, season, parity and calving interval of calving for 305 days MEM, and year, season and parity of birth for CAI as fixed effects. Heritability for 305 days MEM was moderate (0.39) and in the same range of parameters estimated in management systems with medium production levels. Heritability of calving interval was small (0.02) as fertility traits for Xinjiang Brown cattle. Estimates of genetic and environmental correlations between 305 days MEM and CAI were 0.47 and 0.37, respectively. Estimates of genetic variation and heritability indicated that selection would result in genetic improvement of production traits. Estimates of both heritability and genetic variation for CAI were small, which indicates that genetic improvement would be difficult. 展开更多
关键词 Genetic Parameter 305 DAYS MEM calving Interval XINJIANG BROWN CATTLE
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Effects of season calving and managements on lactating curves in two different farms (organic vs conventional) in buffalo cows
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作者 Fiorella Sarubbi Franca Polimeno +3 位作者 Giuseppe Auriemma Giuseppe Maglione Rodolfo Baculo Raffaele Palomba 《Open Journal of Animal Sciences》 2013年第1期83-87,共5页
A total of 5852 records concerning daily milk yield, content of protein and fat, and somatic cell count was recorded in two farms (organic and conventional). Somatic cell count was log10- transformed before analysis b... A total of 5852 records concerning daily milk yield, content of protein and fat, and somatic cell count was recorded in two farms (organic and conventional). Somatic cell count was log10- transformed before analysis because was not normally distributed. The mixed model methodology was used according to a repeated-measures scheme, as the restricted maximum likelihood method to estimate lactation curves at different season of calving and at different calving order. Calving order affected milk yield only in the first three calving order with the lowest production levels in the first six months of the year for both farm;no effect could be observed on fat and protein contents. The organic farm shows the minor milk production (7.77 vs8.10 kg/day/head organic and traditional respectively), but good qualitative characteristics of milk, and minor content of Somatic Cell Count. The milk production is major, in traditional farm, in summer respect the winter (10.4 vs6.34 kgof milk/day/ head). In biological farm no difference between seasons were observed. Peak milk yield occurs, for both farms, at around the 6th - 7th wk of lactation. 展开更多
关键词 BUFFALO ORGANIC and Traditional Farm MILK Yield MILK Constituent SEASON calving
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SN 1054,SN 1006,&Nova WZ Sagittae Calving Antarctic Ice Cap—Global Warming&Moose Die Off Longitude Relationship Deflection Area in Antarctica and USA—WZ Sagittae Impact and Martian Dust Storms
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作者 William P.Sokeland 《Journal of Earth Science and Engineering》 2018年第3期103-121,共19页
The SNIT theory proposes the effects of exploding stars,supernova and nova,on the biosphere of Earth.The feature on our planet that is most sensitive to the incoming energy of an exploding star is sea ice at the poles... The SNIT theory proposes the effects of exploding stars,supernova and nova,on the biosphere of Earth.The feature on our planet that is most sensitive to the incoming energy of an exploding star is sea ice at the poles and this brings in the concept of global warming.The incoming particle streams for SN 1054,SN 1006,and Nova WZ Sagittae have left easily interpreted data noted as calving under the Antarctic ice cap that matches previously predicted longitude locations for the local heat input of the particle streams of the exploding stars.Animal die offs are also caused by the incoming particle streams.The deflection area longitude range for SN 1054 calving produces the correct longitude range for the moose die off beginning in the northern USA in 2006.Some Martian dust storms are created by the wave front of the exploding star debris streams.The explanation of these exploding stars effects using the SNIT theory is the object of this work. 展开更多
关键词 Warming global SUPERNOVA dust calving ANTARCTICA MOOSE Martian.
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Analysis of the Management and Costs Associated with Rearing Pregnant Dairy Heifers in the UK from Conception to Calving
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作者 Alana C. Boulton Jonathan Rushton D. Claire Wathes 《Open Journal of Animal Sciences》 2015年第4期474-485,共12页
Good management of the pregnant heifer is crucial to ensure that she is well grown and healthy and calves down easily before joining the milking herd. This study collected primary data on all aspects of heifer managem... Good management of the pregnant heifer is crucial to ensure that she is well grown and healthy and calves down easily before joining the milking herd. This study collected primary data on all aspects of heifer management on 101 UK farms during heifer pregnancy from conception to calving including farm factors and associated costs of system inputs. A cost analysis workbook was developed to calculate the cost of rearing per heifer for each of the study farms. Associations between cost of rearing and farms factors were determined using linear regression and analysis of variance. Heifers had a mean age of conception of 509 d (range 365 - 700 d) and an age at first calving of 784 d (range 639 - 973 d). The mean total cost of rearing during pregnancy was £450.36 (range £153.11 to £784.00) with a mean daily cost of £1.64 (range £0.56 to £2.86). The inputs contributing the most to cost were feed (32.7%), labour (23.8%) and slurry disposal (11.2%). Total purchased and homegrown feed and grazing contributed between 25.5% and 65.4% of total costs with a mean contribution of 43.6%. The cost of rearing was lowest in spring calving herds and highest in all year round calving herds with intermediate values in autumn and multi block calving herds. The main variables influencing the cost were the number of days spent at grass, age at first calving, calving pattern, breed, herd size and region. Each extra day in age at first calving increased the mean cost of rearing during pregnancy by £0.33/d whereas every extra day at grass reduced the cost by £1.75/d. 展开更多
关键词 HEIFER Cost ANALYSIS Pregnancy calving
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Number of Calving and Its Relationship with Productive Indicators in Nelore Cows
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作者 Atsuko Ikeda Fernando Guzman Vaca +1 位作者 Juan Antonio Pereira Pablo Roberto Marini 《Journal of Agricultural Science and Technology(A)》 2020年第3期151-158,共8页
The objective of this study was to evaluate the relationship of the calving number with productive indicators in Nelore cows in a grazing system in the Bolivian tropics.Retrospective data,corresponding to the period b... The objective of this study was to evaluate the relationship of the calving number with productive indicators in Nelore cows in a grazing system in the Bolivian tropics.Retrospective data,corresponding to the period between 1991 and 2019 referred to 1,566 primiparous and multiparous Nelore breed cows were used.A decrease in the total number of animals was observed from the first to the fifth calving,it was also observed that the age of the first calving was similar in all cows without significant differences,showing that longevity is not associated with the age at the first calving.Live weight presented significant differences(p≤0.05),according to the number of calvings;the fourth and fifth calving cows are the heaviest.Weight of calf at birth did not show a relationship with the number of calvings either.However,it does so in the weight of calf at weaning,which increases from the first to the fifth calving with significant differences(p≤0.05).There were significant differences(p≤0.05)for the interval between calvings,decreasing as the calvings progressed.It is concluded that there is a relationship between the number of calving with productive indicators in Nelore cows in a grazing system in the Bolivian tropics,fundamentally those efficiency variables where longevity is important. 展开更多
关键词 Zootechnic efficiency interval between calvings CALF weight at WEANING ACCUMULATIVE production grazing system
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Most Probable Producing Ability of Bali Cows for Calving Interval and Calf Growth Performance
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作者 Andoyo Supriyantono Trisiwi Wahyu Widayati Iriani Sumpe 《Journal of Agricultural Science and Technology(A)》 2017年第6期426-431,共6页
Most probable producing ability (MPPA) is the one factor used to compare the performance potential of dam based on the data of their progeny. The purpose of the research was to study the genetic ability of weaning w... Most probable producing ability (MPPA) is the one factor used to compare the performance potential of dam based on the data of their progeny. The purpose of the research was to study the genetic ability of weaning weight, yearling weight and calving interval of Bali cows. The weaning weight data of 296 cows derived from 99 dams, yearling weight data of 245 cows derived from 86 dams and cabAng interval data of 194 cows from 63 dams were used to estimate repeatability and MPPA of Bali cows in a herd for the three traits. Repeatability of three traits was estimated by analysis of intra-class correlation, and these in turn were used for calculating the estimated MPPA of cows. The results showed that the means of weaning weight of males and females were 95.56 ± 17.25 kg and 87.57 ± 18.45 kg, respectively; means of yearling weight were 143.39 ±25.78 kg and 136.90 ± 22.01 kg, respectively; and mean calving interval was 391.62±22.59 d. The estimated repeatability of weaning weight, yearling weight and calving interval were 0.006 ±0.059, 0.022 ± 0.068 and 0.115 ± 0.078, respectively. The best 10 dams in the herd based on the estimates of MPPA for weaning weight, yearling weight and calving interval were not the same for the three traits. 展开更多
关键词 Weaning weight yearling weight calving interval most probable producing ability Bali cows
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Yak Calving Interval and Calving Efficiency
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作者 王敏强 《中国草食动物》 2005年第z2期203-204,共2页
The results of 439 times of calving interval(CI) from 161 yak cows showed that the average CI is 459(se=131)d. The CI with 3 to 6 calving numbers is 25~48 d shorter than that of 1 to 2 and above 7 calving numbers. Al... The results of 439 times of calving interval(CI) from 161 yak cows showed that the average CI is 459(se=131)d. The CI with 3 to 6 calving numbers is 25~48 d shorter than that of 1 to 2 and above 7 calving numbers. Although slaughtering a great number of calves during the late September and early October do bring about relatively higher calving rate that is mos yak cowst can give 3,4,5 and 6calves during 4,5,6 and 7 years old respectively. This makes major calving months shift from April or May to June. 展开更多
关键词 YAK COW calving NUMBER calving EFFICIENCY calving MONTH
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TRANSPLANTATION OF BOVINE EMBRYOS FER TILIZED in vitro AND SUBSEQUENT CALVING
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作者 旭日干 张锁链 +3 位作者 薛晓先 廛洪武 庞也非 斯琴 《Chinese Science Bulletin》 SCIE EI CAS 1991年第11期948-950,共3页
The bovine embryos used for nonsurgical transfer should be morulae or blastocysts which are generally obtained from donor cow through superovulation and insemination. Due to the high cost of the embryos, the spread of... The bovine embryos used for nonsurgical transfer should be morulae or blastocysts which are generally obtained from donor cow through superovulation and insemination. Due to the high cost of the embryos, the spread of embryo transfer is influenced to certain extent. In recent years, in vitro fertilization (IVF)technique has been adopted abroad to expand the source of embryos. The methods employed normally were culturing the embryos in rabbit’s or sheep’s oviducts (in vivo culture) to overcome '8—16-cell block', the morula or blastocyst developed in vivo was recovered and then transferred to recipients. However, the research concerning in vitro culture of IVF ova to the morula-blastocvst stage was 展开更多
关键词 in VITRO FERTILIZATION EMBRYO transfer calving.
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The roles of calving migration and climate change in the formation of the weak genetic structure in the Tibetan antelope(Pantholops hodgsonii)
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作者 Jiarui CHEN Gonghua LIN +3 位作者 Wen QIN Jingyan YAN Tongzuo ZHANG Jianping SU 《Integrative Zoology》 SCIE CSCD 2019年第3期248-258,共11页
Geographical barriers and distance can reduce gene exchange among animals,resulting in genetic divergence of geographically isolated populations.The Tibetan antelope(Pantholops hodgsonii)has a geographical range of ap... Geographical barriers and distance can reduce gene exchange among animals,resulting in genetic divergence of geographically isolated populations.The Tibetan antelope(Pantholops hodgsonii)has a geographical range of approximately 1600 km across the Qinghai-Tibet Plateau,which comprises a series of tall mountains and big rivers.However,previous studies indicate that there is little genetic differentiation among their geographical­ly delineated populations.To better understand the genetic structure of P.hodgsonii populations,we collected 145 samples from the 3 major calving regions,taking into consideration their various calving grounds and mi­gration routes.We used a combination of mitochondrial sequences(Cyt b,ATPase,D-loop and COX I)to inves­tigate the genetic structure and the evolutionary divergence of the populations.Significant,albeit weak,genetic differentiation was detected among the 3 geographical populations.Analysis of the genetic divergence process revealed that the animals gradually entered a period of rapid genetic differentiation approximately 60000 years ago.The calving migration of P.hodgsonii cannot be the main cause of their weak genetic structure because this cannot fully homogenize the genetic pool.Instead,the geological and climatic events as well as the coupling vegetation succession process during this period have been suggested to greatly contribute to the genetic struc­ture and the expansion of genetic diversity. 展开更多
关键词 calving migration climate change genetic structure Tibetan antelope vegetation succession
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Preweaning period is a critical window for rumen microbial regulation of average daily gain in Holstein heifer calves 被引量:2
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作者 Shengyang Xu Chong Jiao +1 位作者 Qiyu Diao Yan Tu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期396-411,共16页
Background Rumen bacterial groups can affect growth performance,such as average daily gain(ADG),feed intake,and efficiency.The study aimed to investigate the inter-relationship of rumen bacterial composition,rumen fer... Background Rumen bacterial groups can affect growth performance,such as average daily gain(ADG),feed intake,and efficiency.The study aimed to investigate the inter-relationship of rumen bacterial composition,rumen fermentation indicators,serum indicators,and growth performance of Holstein heifer calves with different ADG.Twelve calves were chosen from a trail with 60 calves and divided into higher ADG(HADG,high pre-and post-weaning ADG,n=6)and lower ADG(LADG,low pre-and post-weaning ADG,n=6)groups to investigate differences in bacterial composition and functions and host phenotype.Results During the preweaning period,the relative abundances of propionate producers,including g_norank_f_Butyricicoccaceae,g_Pyramidobacter,and g_norank_f_norank_o_Clostridia_vadin BB60_group,were higher in HADG calves(LDA>2,P<0.05).Enrichment of these bacteria resulted in increased levels of propionate,a gluconeogenic precursor,in preweaning HADG calves(adjusted P<0.05),which consequently raised serum glucose concentrations(adjusted P<0.05).In contrast,the relative abundances of rumen bacteria in post-weaning HADG calves did not exert this effect.Moreover,no significant differences were observed in rumen fermentation parameters and serum indices between the two groups.Conclusions The findings of this study revealed that the preweaning period is the window of opportunity for rumen bacteria to regulate the ADG of calves. 展开更多
关键词 Average daily gain CALVES Preweaning period Rumen microbiota
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Effect of organic mineral supplementation in reducing oxidative stress in Holstein calves during short‑term heat stress and recovery conditions 被引量:1
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作者 A-Rang Son Seon-Ho Kim +3 位作者 Mahfuzul Islam Michelle Miguel Ye Pyae Naing Sang-Suk Lee 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期812-825,共14页
Background This study investigated the effects of inorganic and organic minerals on physiological responses,oxidative stress reduction,and rumen microbiota in Holstein bull calves(123.81±9.76 kg;5 months old)duri... Background This study investigated the effects of inorganic and organic minerals on physiological responses,oxidative stress reduction,and rumen microbiota in Holstein bull calves(123.81±9.76 kg;5 months old)during short-term heat stress(HS)and recovery periods.Eight Holstein calves were randomly assigned to four treatment groups:no mineral supplementation(Con),inorganic minerals(IM),organic minerals(OM),and high-concentration organic minerals(HOM)and two thermal environments(HS and recovery)using 4×2 factorial arrangement in a crossover design of four periods of 35 d.Calves were maintained in a temperature-controlled barn.The experimental period consisted of 14 d of HS,14 d of recovery condititon,and a 7-d washing period.Results Body temperature and respiration rate were higher in HS than in the recovery conditions(P<0.05).Selenium concentration in serum was high in the HOM-supplemented calves in both HS(90.38μg/dL)and recovery periods(102.00μg/dL)(P<0.05).During the HS period,the serum cortisol was 20.26 ng/mL in the HOM group,which was 5.60 ng/mL lower than in the control group(P<0.05).The total antioxidant status was the highest in the OM group(2.71 mmol Trolox equivalent/L),followed by the HOM group during HS,whereas it was highest in the HOM group(2.58 mmol Trolox equivalent/L)during the recovery period(P<0.05).Plasma malondialdehyde and HSP70 levels were decreased by HOM supplementation during the HS and recovery periods,whereas SOD and GPX levels were not significantly affected(P>0.05).The principal coordinate analysis represented that the overall rumen microbiota was not influenced by mineral supplementation;however,temperature-induced microbial structure shifts were indicated(PERMANOVA:P<0.05).At the phylum level,Firmicutes and Actinobacteria decreased,whereas Fibrobacteres,Spirochaetes,and Tenericutes increased(P<0.05),under HS conditions.The genus Treponema increased under HS conditions,while Christensenella was higher in recovery conditions(P<0.05).Conclusion HOM supplementation during HS reduced cortisol concentrations and increased total antioxidant status in Holstein bull calves,suggesting that high organic mineral supplementation may alleviate the adverse effects of HS. 展开更多
关键词 Antioxidant status Heat stress Holstein bull calves Organic mineral supplementation Oxidative stress
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Bacteria colonization and gene expression related to immune function in colon mucosa is associated with growth in neonatal calves regardless of live yeast supplementation
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作者 Koki Nishihara Clothilde Villot +2 位作者 Lautaro Cangiano Le Luo Guan Michael Steele 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第5期1980-1995,共16页
Background As Holstein calves are susceptible to gastrointestinal disorders during the first week of life,understanding how intestinal immune function develops in neonatal calves is important to promote better intesti... Background As Holstein calves are susceptible to gastrointestinal disorders during the first week of life,understanding how intestinal immune function develops in neonatal calves is important to promote better intestinal health.Feeding probiotics in early life may contribute to host intestinal health by facilitating beneficial bacteria colonization and developing intestinal immune function.The objective of this study was to characterize the impact of early life yeast supplementation and growth on colon mucosa-attached bacteria and host immune function.Results Twenty Holstein bull calves received no supplementation(CON)or Saccharomyces cerevisiae boulardii(SCB)from birth to 5 d of life.Colon tissue biopsies were taken within 2 h of life(D0)before the first colostrum feeding and 3 h after the morning feeding at d 5 of age(D5)to analyze mucosa-attached bacteria and colon transcriptome.Metagenome sequencing showed that there was no difference inαandβdiversity of mucosa-attached bacteria between day and treatment,but bacteria related to diarrhea were more abundant in the colon mucosa on D0 compared to D5.In addition,q PCR indicated that the absolute abundance of Escherichia coli(E.coli)decreased in the colon mucosa on D5 compared to D0;however,that of Bifidobacterium,Lactobacillus,and Faecalibacterium prausnitzii,which could competitively exclude E.coli,increased in the colon mucosa on D5 compared to D0.RNA-sequencing showed that there were no differentially expressed genes between CON and SCB,but suggested that pathways related to viral infection such as“Interferon Signaling”were activated in the colon mucosa of D5 compared to D0.Conclusions Growth affected mucosa-attached bacteria and host immune function in the colon mucosa during the first 5 d of life in dairy calves independently of SCB supplementation.During early life,opportunistic pathogens may decrease due to intestinal environmental changes by beneficial bacteria and/or host immune function.Predicted activation of immune function-related pathways may be the result of host immune function development or suggest other antigens in the intestine during early life.Further studies focusing on the other antigens and host immune function in the colon mucosa are required to better understand intestinal immune function development. 展开更多
关键词 Colon biopsy Dairy calves RNA-sequencing Saccharomyces cerevisiae boulardii 16S rRNA amplicon-sequencing
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Unprecedented Retreat in a 50-Year Observational Record for Petermann Glacier, North Greenland 被引量:1
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作者 Ola M. JOHANNESSEN Mohamed BABIKER Martin W. MILES 《Atmospheric and Oceanic Science Letters》 CSCD 2013年第5期259-265,共7页
Petermann Glacier is a marine-terminating outlet glacier that had a 70 km-long floating ice tongue prior to a ~ 270 km2 calving event that was observed from satellite sensors in August 2010,shortening the ice tongue ... Petermann Glacier is a marine-terminating outlet glacier that had a 70 km-long floating ice tongue prior to a ~ 270 km2 calving event that was observed from satellite sensors in August 2010,shortening the ice tongue by ~ 27 km.Further,in July 2012,another 10 km was lost through calving.In order to understand these events in perspective,here the authors perform a long-term data analysis of Petermann Glacier calving-front variability and ice velocity for each year in the 1990s-2000s,supplemented by available observations from the previous three decades.Five major (on the order of 100 krm2) calving events are identified,with ~ 153 km2 calved from 1959 to 1961,~ 168 km2 in 1991,~ 71 km2 in 2001,~ 270 km2 in 2010,and ~ 130 km2 in 2012-as well as ~ 31 k m2 calved in 2008.The increased frequency of major calving events in recent years has left the front terminus position retreated nearly 25 km beyond the range of observed in previous decades.In contrast,stable ice-dynamics are suggested from ice-velocity measurements made each year between 1993-2012,which are on average 1063 m yr-1,with limited interannual variability and no significant trend; moreover,there is no apparent relationship between ice-velocity variability and calving events.The degree to which the massive calving events in 2010 and 2012 represent natural episodic variability or a response to atmospheric and/or oceanic changes remains speculative; however,melt-induced weakening of the floating ice tongue in recent years is strongly suggested. 展开更多
关键词 GREENLAND outlet glaciers iceberg calving satellite remote sensing
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Quality Analysis of Dairy Herd Improvement Data from Henan Province 被引量:1
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作者 Zhen ZHANG Xiaoli REN +3 位作者 Lei YAN Yuefei YAN Fanjun GENG Yanqin SUN 《Agricultural Science & Technology》 CAS 2017年第1期151-155,188,共6页
The dairy herd improvement data from Henan Province were analyzed statistically to establish screening criteria for relevant data, thereby laying a foundation for genetic evaluation of dairy cows. With the 2 152 451 t... The dairy herd improvement data from Henan Province were analyzed statistically to establish screening criteria for relevant data, thereby laying a foundation for genetic evaluation of dairy cows. With the 2 152 451 test-day records about 155 893 Chinese Holstein dairy cows collected by the Henan Dairy Herd Improvement Center from January 2008 to April 2016, the dynamics of test times during a complete lactation, test interval during a complete lactation, days in milk (DIM) of first test-day record, daughter descendant number and herd number of bull, age at first calving and pedigree integrity rate among different years and different herd sizes were analyzed by MEANS order of SAS 9.4. In addition, the data that were applicable to genetic evaluation were screened by SQL program. The results showed that during 2008-2015, the number of cow individuals participating in DHI in Henan Province increased from 7 379 to 93 706; the test-day milk yield increased from 19.91 to 24.05 kg; the somatic cell count reduced from 411.09×10^3 to 277.08×10^3 cells/ml; the percentage of cows with DIM ranging from 5-305 d reached 70.92%; the average test times increased from 3.20 to 6.31 times; the test interval decreased from 70.22 to 33.83 d; the dairy cows with age at first calving of 25 months were dominant, accounting for 12.57%; the bulls whose daughter descendant number was 20 or more and the daughters were distributed in 10 or more farms accounted for 6.05%; the one-generation pedigree integrity rate was 82.54%; the percentage of data that could be used for genetic evaluation was screened as 20.67%, which was lower than the results of other similar studies. 展开更多
关键词 Dairy herd improvement data quality Test times Test interval DIM of first test-day record Daughter descendant number and herd number of bull age at first calving Pedigree integrity rate
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Legg-Calvè-Perthes综合征
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作者 王延宙 赵逢华 《山东医药》 CAS 北大核心 2003年第21期51-51,共1页
关键词 Legg—Calvè—Perthes综合征 小儿 髋部异常 股骨头缺血性坏死 流行病学 病因 诊断 治疗
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MRI在Legg-Calve-Perthes disease中的应用
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作者 黄钰坚 方挺松 《中国CT和MRI杂志》 2012年第4期106-109,116,共5页
目的探讨LCP病的MRI表现和诊断价值。方法回顾性分析14例LCP病(15髋)临床和MRI资料,研究LCP病不同分期MRI影像学表现。结果缺血坏死期,2髋;血运重建期,6髋;修复期,7髋。MRI显示髋关节滑膜炎(15髋),关节积液(15髋),关节面滑膜侵蚀(5髋),... 目的探讨LCP病的MRI表现和诊断价值。方法回顾性分析14例LCP病(15髋)临床和MRI资料,研究LCP病不同分期MRI影像学表现。结果缺血坏死期,2髋;血运重建期,6髋;修复期,7髋。MRI显示髋关节滑膜炎(15髋),关节积液(15髋),关节面滑膜侵蚀(5髋),骨髓水肿(7髋),髋臼和股骨头软骨增厚(6髋),扁平髋(2髋),股骨干骺端和股骨头骨骺间骨桥(3髋)。结论 MRI是评价LCP病有效工具,可应用于诊断股骨头坏死,为疾病准确分期、各种并发症的发现及患者预后,提供重要信息;指导制定非手术和手术治疗方案具有重要意义。此外MRI还可以鉴别其它儿童髋关节疾病。 展开更多
关键词 Legg—Calve—Perthes病 核磁共振成像 髋关节 儿童
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