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Csilla Hatvani Orsolya G. Balogh Tamás Endr?di Zsolt Abonyi-Tóth István Holló John P. Kastelic Gy?rgy Gábor 《Canadian journal of veterinary research》2013,77(3):218-220
The objective of this study was to determine rates of estrus and conception in lactating multiparous Holstein cows given 500 μg of cloprostenol intramuscularly after detection of the following ≥ 60 d after parturition: a solid corpus luteum (CL), a CL with a nonechodense cavity ≤ 20 mm in diameter (CLcav), a luteal cyst (cavity > 20 mm in diameter and a luteinized wall > 3 mm in diameter), or a follicular cyst (cavity > 20 mm and a luteinized wall ≤ 3 mm in diameter). The estrus rates were 335/419 (80.0%), 183/223 (82.1%), 170/182 (93.4%), and 44/87 (50.6%), respectively (P < 0.0001), and the conception rates 30 to 36 d after insemination among the estrous cows with an apparently normal mucus discharge were 130/285 (45.6%), 44/141 (31.2%), 39/79 (49.4%), and 19/30 (63.3%), respectively (P < 0.002). Compared with a solid CL, a CLcav did not affect the estrus rate but significantly reduced the conception rate (P < 0.05), and the estrus rates were significantly higher and lower in cows with a luteal or follicular cyst, respectively (P < 0.05). 相似文献
43.
Comparison of Ethylene Glycol and Propylene Glycol for the Vitrification of
Immature Porcine Oocytes
Tamás SOMFAI Michiko NAKAI Fuminori TANIHARA Junko NOGUCHI Hiroyuki KANEKO Naomi KASHIWAZAKI István EGERSZEGI Takashi NAGAI Kazuhiro KIKUCHI 《The Journal of reproduction and development》2013,59(4):378-384
Our aim was to optimize a cryoprotectant treatment for vitrification of immature porcine
cumulus-oocyte complexes (COCs). Immature COCs were vitrified either in 35% ethylene
glycol (EG), 35% propylene glycol (PG) or a combination of 17.5% EG and 17.5% PG. After
warming, the COCs were in vitro matured (IVM), and surviving oocytes were
in vitro fertilized (IVF) and cultured. The mean survival rate of
vitrified oocytes in 35% PG (73.9%) was higher (P<0.05) than that in 35% EG (27.8%).
Oocyte maturation rates did not differ among vitrified and non-vitrified control groups.
Blastocyst formation in the vitrified EG group (10.8%) was higher (P<0.05) than that in
the vitrified PG group (2.0%) but was lower than that in the control group (25.0%).
Treatment of oocytes with 35% of each cryoprotectant without vitrification revealed a
higher toxicity of PG on subsequent blastocyst development compared with EG. The
combination of EG and PG resulted in 42.6% survival after vitrification. The maturation
and fertilization rates of the surviving oocytes were similar in the vitrified, control
and toxicity control (TC; treated with EG+PG combination without cooling) groups.
Blastocyst development in the vitrified group was lower (P<0.05) than that in the
control and TC groups, which in turn had similar development rates (10.7%, 18.1% and
23.3%, respectively). In conclusion, 35% PG enabled a higher oocyte survival rate after
vitrification compared with 35% EG. However, PG was greatly toxic to oocytes. The
combination of 17.5% EG and 17.5% PG yielded reasonable survival rates without toxic
effects on embryo development. 相似文献
44.
European corn borer (Ostrinia nubilalis Hbn., Lepidoptera: Crambidae): comparing the performance of a new bisexual lure with that of synthetic sex pheromone in five countries 
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Long polar fimbriae (Lpf) are recently discovered adhesins and increasingly important genetic markers of pathogenic Escherichia coli strains. The presence and genotype diversity of Lpf operons was screened in a collection of 97 Escherichia coli O157 strains representing different pathotypes, isolated from healthy cattle (n = 43) and human patients (n = 54) in several countries. Individual structural genes of Lpf were scanned by PCR, and allelic variants were detected with a recently developed typing scheme. Ninety-five strains carried at least one whole Lpf operon (genes lpfABCD and/or lpfABCDE). The 64 enterohaemorrhagic (EHEC) and 24 enteropathogenic (EPEC) strains all carried two Lpf operons, allele 3 of lpfA1 and allele 2 of lpfA2, a combination characteristic of the O157:H7/NM serotype. Out of the 9 bovine atypical (AT; stx-, eae-) strains, 7 carried one complete Lpf operon, allele 1 of lpfA2. The atypical strains belonged to main phylogenetic groups A and B1, while the EHEC and EPEC strains were from group D. Lpf variants carried by the 72 strains of the Escherichia coli Reference Collection (ECOR) were determined with the same typing scheme. Alleles were detected in 25 strains, of which 6 were found negative for the respective Lpf operons in earlier studies. The marker value of the Lpf allelic combination for the O157:H7/NM serotype was confirmed, and further evidence was given for the presence of at least two different genetic lineages of atypical bovine E. coli O157 strains. 相似文献
46.
Csaba Tölgyesi Zoltán Bátori Róbert Gallé István Urák Tibor Hartel 《Strength and Conditioning Journal》2018,71(5):571-577
Rangelands with scattered trees are complex and dynamic systems with a long history in Europe. Generally referred to as “wood-pastures,” they are considered to have outstanding conservation value. Thorny shrubs are important for supporting the biodiversity of these wooded rangelands, as well as facilitating the regeneration of trees by acting as nurse species. We assess the direct effects of temporary shrub encroachment under the cover of mature sparse trees on overall plant and habitat diversity. We surveyed the herb layer of the main landscape features of a wood-pasture: open pasture, trees with a grass understory, trees with shrubs, and adjacent forest edges. The herb layer under trees with shrubs resembled that of forest edges more than open pastures and trees with grass. Trees with grass had a higher cover of ruderal species than trees with shrubs, while forest edges and open pastures had a lower cover of them. Forest species were absent from open pastures but were well represented in the other sites. The herb layer of trees with shrubs and forest edges had similar cover values, while trees with grass had a significantly lower cover of herbs than the other types. Trees with shrubs had higher species richness than any of the other three landscape features and had a much higher proportion of diagnostic species. We conclude that the scattered trees and shrubs of the studied silvopastoral system have additive facilitative effects on their understory, probably through modifying the microenvironment and grazing pressure, leading to the formation of temporary diversity hot spots with distinct vegetation. Thus maintaining a moderate level of shrub-encroachment under sparse trees is recommended for not only creating safe havens for tree recruitment but also increasing the overall species and habitat diversity of wood-pastures. 相似文献
47.
Porcine circovirus type 1 (PCV1) is considered to be a non-pathogenic virus detected in cell cultures, vaccines or products used for cell culture preparations, all of them of porcine origin. Serological evidence and genetic studies suggested that PCV1 was widespread in domestic pigs. The presence of PCV1 in wild boars in Germany was also described using serological methods. This paper reports the first detection of PCV1 in Hungarian wild boars. Samples were collected at slaughterhouses and processed for polymerase chain reactions. The complete genome of PCV1 detected in the samples was determined and compared with the available PCV1 sequences of the GenBank database. The genomes formed two distinct clusters with minimum differences, where the Hungarian wild boar PCV1 (WB-H8) grouped together with genomes originating from domestic swine from China and Australia and with a genome detected in a porcine pepsin product. 相似文献
48.
Genetic diversity of porcine reproductive and respiratory syndrome virus strains circulating in Hungarian swine herds 总被引：3，自引：0，他引：3
Balka G Hornyák A Bálint A Kiss I Kecskeméti S Bakonyi T Rusvai M 《Veterinary microbiology》2008,127(1-2):128-135
Analysis of 37 ORF5 sequences of Hungarian porcine reproductive and respiratory syndrome virus (PRRSV) strains revealed that most of them (35) belonged to the European genotype, forming distinct subgroups, reflecting the exceptional diversity of Eastern European strains. Twelve vaccine-like strains were also found in non-vaccinated animals. Two strains belonged to the American genotype showing 90-91% nucleotide identity to the "Quebec" Canadian reference strain. The analysis of the putative ectodomains and their N-linked glycosylation sites of the vaccine strain and its variants suggested selective pressure on the first ectodomain, by a consistent amino acid change on epitope B and by loosing a glycosylation site in the otherwise conserved N-46 position. 相似文献
49.
Utilisation of <Emphasis Type="Italic">Aegilops</Emphasis> (goatgrass) species to widen the genetic diversity of cultivated wheat 总被引：2，自引：0，他引：2
Wild Aegilops species related to cultivated wheat (Triticum spp.) possess numerous genes of agronomic interest and can be valuable sources of resistance to diseases, pests and extreme
environmental factors. These genes can be incorporated into the wheat genome via intergeneric crossing, following, where necessary,
the development of chromosome addition and substitution lines from the resulting hybrids. The transfer of a single segment
from an alien chromosome can be achieved by translocations. The Aegilops (goatgrass) species, which are the most closely related to wheat, exhibit great genetic diversity, the exploitation of which
has been the subject of experimentation for more than a century. The present paper gives a survey of the results achieved
to date in the field of wheat–Aegilops hybridisation and gene transfer. The Aegilops genus consists of 11 diploid, 10 tetraploid and 2 hexaploid species. Of these 23 Aegilops species, most of the diploids (Ae. umbellulata Zhuk., Ae. mutica Boiss., Ae. bicornis (Forssk.) Jaub. & Spach, Ae. searsii Feldman & Kislev ex Hammer, Ae. caudata L., Ae. sharonensis Eig, Ae. speltoides Tausch, Ae. longissima Schweinf. & Muschl.) and several polyploids (Ae. ventricosa Tausch, Ae. peregrina (Hack. In J. Fraser) Marie & Weiller, Ae. geniculata Roth, Ae. kotschyi Boiss., Ae. biuncialis L.) have been used to develop wheat–Aegilops addition lines. Wheat–Aegilops substitution lines were developed using several species, including Ae. umbellulata, Ae. caudata, Ae. tauschii, Ae. speltoides, Ae. sharonensis, Ae. longissima and Ae. geniculata. Translocations carrying genes responsible for useful agronomic traits were developed with Ae. umbellulata, Ae. comosa, Ae. ventricosa, Ae. longissima, Ae. speltoides and Ae. geniculata. A large number of genes were transferred from Aegilops species to cultivated wheat, including those for resistance to leaf rust, stem rust, yellow rust and powdery mildew, and
various pests (cereal cyst nematode, root knot nematode, Hessian fly, greenbug). Many molecular markers are linked to these
resistance genes. The development of new molecular markers is also underway. There are still many untapped genetic resources
in Aegilops species that could be used as resistance sources for plant breeding. 相似文献
50.
Katalin Berecz Lívia Simon‐Sarkadi István Ragasits Sándor Hoffmann 《Archives of Agronomy and Soil Science》2013,59(5-6):389-398
The cultivation of Triticum spelta (spelt) has no tradition in Hungary. In recent years the interest towards this old species renewed in many countries. This high‐nutritional cereal, which has a high ash and fibre content, can be used in many health‐oriented grain‐based food products. Therefore, field experiments have been conducted for some years to test the performance of this species under home growing conditions. Here we report the results of analyses for some important quality parameters of grain samples from the 1996/97 season in comparison with those of older and new home‐grown bread wheat cultivars. Three common wheat cultivars and one advanced spelt line were grown on small plots fertilised with an NPK dose necessary to reach the highest yield and quality. Spikes were sampled weekly from the time of 70–77% grain moisture to full ripening. The grains were analysed for ash, N, P and K content and amino acid composition. Concentrations of 16 other macro + micro elements and in the ripe grains, baking quality parameters were also assessed. The grain development of spelt showed a remarkable time‐lag compared to that of the common wheat cultivars. However, the highest thousand‐grain‐masses, ash, N, and P concentrations were measured in this cultivar after milk ripening. The grains of spelt contained the macro‐nutrient Mg and four micro‐nutrients (Zn, Mn, Fe, Cu) in higher concentrations compared to those of the common wheat varieties. The total and essential amino acid concentrations measured in the ripe grains of spelt were also remarkably higher. Although its wet gluten content (47.5%) was considerably higher than that of the bread wheat cultivars, its breadmaking quality was poor. 相似文献