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91.
Escrivão RJ Webb EC Garcês AP Grimbeek RJ 《Tropical animal health and production》2012,44(7):1779-1782
Sixty multiparous Brahman-type cows were randomly selected in the early postpartum period and equally allocated into a calf removal group (RG) and a non-removal group (NRG). Calves from cows in the RG were removed for 48 h prior to the breeding season and returned afterwards, whereas in the NRG, calves remained with their dams until weaning. Weaning weights were corrected to 205?days. Conception rates (CRs) were 76?% for RG and 55?% for NRG but did not differ (p?>?0.05). CR was correlated with calving to breeding interval and body condition score at the onset of the breeding season. Product-limit survival curves vs breeding to conception interval differed significantly (p?相似文献
92.
Dominant bacteria in soils of Marble Point and Wright Valley, Victoria Land, Antarctica 总被引：1，自引：0，他引：1
Jackie. M. Aislabie Kim-Ly Chhour Shingo Miyauchi Ron F. Paetzold 《Soil biology & biochemistry》2006,38(10):3041-3056
A combination of culture-independent and culturing methods was used to assess the diversity of soil bacterial communities from four locations along 77 °S in Victoria Land, Antarctica. Soil samples were from the coast at Marble Point, in the Wright Valley from Bull Pass and near Lake Vanda, and from Mt. Fleming near the polar plateau. Total carbon and nitrogen, and water content of the soils were low, whereas total P was very high. The pH of the soils varied from extremely alkaline to slightly acid and electrical conductivity was medium to high on the coast and very high in inland soils from Bull Pass and Mt. Fleming. The average monthly air temperature was similar (−18 °C to −24 °C) at all the sites; however, in summer surface soil temperatures were >0 °C at Marble Point and in the Wright Valley for a total of 1100 and 1700 h, respectively. Marble Point soil had the most potential to support bacterial growth and activity with a mean total of 310 h per year when surface soils had a liquid volumetric soil moisture content >5%. Highest counts of culturable heterotrophs occurred in soil from Marble Point, whereas Mt. Fleming soil contained few organisms and had no liquid soil moisture recorded. Seven hundred and twenty-eight clones and 71 bacterial isolates were screened by restriction fragment length polymorphisms, and representatives of those dominant ribotypes that occurred more than 3 times were sequenced. The dominant ribotypes grouped within the bacterial divisions Bacteroidetes, Actinobacteria, Proteobacteria, Thermus-Deinococcus, Acidobacteria, Firmicutes and Cyanobacteria. The closest relatives of the amplicon library clones or cultured bacteria include the genera Hymenobacter, Gillisia, Arthrobacter, Rubrobacter, Friedmanniella, Deinococcus and Leptolyngbya. Many of the clones and bacteria were most similar to others from Antarctic sources, in particular a cyanobacterium-dominated cryptoendolithic community in Beacon sandstone. Some ribotypes were more prevalent in drier soils of the Wright Valley, including relatives of Deinococcus, Rubrobacter and clone FBP460 from Beacon sandstone. Bacterial communities from Marble Point soils were more diverse than those of the Wright Valley. Very few bacteria were isolated from Mt. Fleming soil. 相似文献
93.
Christopher M. Richards Michael F. Antolin Ann Reilley Jackie Poole Christina Walters 《Genetic Resources and Crop Evolution》2007,54(4):837-848
Genebanks complement other conservation programs because they preserve genetic diversity needed for future breeding and restoration.
We evaluated efficiency of capturing genetic diversity, using endangered Zizania texana (Texas wild rice) as a model for plants with recalcitrant seeds. This perennial aquatic grass is restricted to 4 km of the
San Marcos River in Texas. An early conservation collection included plants from stands throughout the river, based on the
assumption stands would be unique genotypes. Using microsatellite markers, we found that genetic diversity was concentrated
in five of 15 large, demographically stable stands; 96 stands smaller than 2 m2 contributed no unique alleles. High heterozygosity and few duplicate genotypes suggested that sexual reproduction occurs
more often than presumed. Simulations of stratified sampling of large stands captured all alleles in only 45 individuals,
while random sampling along the river captured much less diversity. The early conservation collection captured as much diversity
as expected from random sampling. Texas wild rice stands resemble a mainland-island metapopulation; our analyses suggest that
stratified sampling maximizes genetic diversity for this population dynamic. Demographic and genetic information is important
for validating the design of efficient ex situ collections and guiding in situ conservation. 相似文献
94.
95.
Claire Laugier Nathalie Foucher Corinne Sevin Albertine Leon Jackie Tapprest 《Journal of Equine Veterinary Science》2011,31(3):116-123
The main causes of abortion in mares in France were studied from 1,822 cases submitted for necropsy. The cause of abortion was established in 74.9% of cases (n = 1,365). Fetoplacental infections (n = 869) represented 63.7% of diagnosed abortions. A noninfectious cause was found in 27.2% of cases (n = 496). Of the infectious causes of abortion, the vast majority were caused by bacteria (n = 695; 79.9%), followed by viruses (15.1%), and then fungi (1.8%). In 27 cases (3.1%), no specific pathogenic agent could be identified despite the presence of lesions. Of the noninfectious causes of abortion, umbilical cord abnormalities were the most frequent (n = 300; 60.5%). Placental villous hypoplasia represented the second most frequent cause (17.3%). This was followed by lethal congenital malformations (6.9%). The causes of placental insufficiency other than placental villous hypoplasia—twins, placental edema, placental premature separation, and body pregnancy—were less frequent. The diagnosis of equine abortion cases examined in Normandy seemed to be somewhat in agreement with the findings reported in Kentucky and the United Kingdom. In this study, about 60% of the cases were associated with a condition involving the allantochorion or the umbilical cord. Thus, to enhance diagnostic success, it is of prime importance to submit the fetal membranes along with the fetus for necropsy. 相似文献
96.
- 1. The intensity of marine activities in the exclusive economic zone (EEZ) of British Columbia, Canada, was quantified.
- 2. Humans use the ocean for a multitude of purposes, many of which have a direct impact on marine life and habitat. Yet such uses are seldom assessed in an integrated fashion.
- 3. Using a GIS approach, spatial information for 39 marine activities was mapped, including commercial and recreational fishing areas, transportation and infrastructure uses, and terrestrial activities along the coast of British Columbia.
- 4. A relative scale was used to rank both the impact of marine activities and the extent of stressors beyond the location of occurrence. Limited information on the latter led to the application of three ranges of buffer distances to the data (0–1 km, 0–5 km, and 0–25 km).
- 5. The most conservative estimate (?1 km buffers) indicates at least 83% of the continental shelf and slope of British Columbia is currently being used by humans. The largest buffer assumption shows 98% of the continental shelf and slope being affected by stressors from anthropogenic activities.
- 6. This analysis provides a baseline for assessing future changes in the state of British Columbia's marine environment, and could assist in identifying areas of conservation potential.
97.
Effect of 6–8 weeks of oral ursodeoxycholic acid administration on serum concentrations of fasting and postprandial bile acids and biochemical analytes in healthy dogs 
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随着社会高收入群体的不断壮大,世界禽肉产业对此类客户的消费需求日益重视,深加工行业在全球范嗣内一跃崛起.尽管目前这一市场的发展速度在不同国家之间差异很大,但迄今为止,好像还没有哪一个国家能比美国更能引领这一领域的技术潮流. 相似文献
99.
2008年年初,在美国亚特兰大召开了家禽博览会,同期举行了由美国禽蛋协会组织的国际家禽科学研讨会,本文对相关成果进行介绍. 相似文献
100.
Evrard Olivier Durand Roxanne Foucher Anthony Tiecher Tales Sellier Virginie Onda Yuichi Lefèvre Irène Cerdan Olivier Laceby J. Patrick 《Journal of Soils and Sediments》2019,19(9):3290-3301
Journal of Soils and Sediments - Spectrocolourimetric measurements provide a relatively inexpensive, quick and non-destructive alternative to the analysis of geochemical and organic matter... 相似文献