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81.
In a herd of German Improved Fawn breed of goat in the year 2000 neonatal kid losses due to congenital copper deficiencies were observed. To clarify the problems and to prevent losses in the next breeding season serum copper levels of 10 dams and four control Boer goats were investigated at four time points during one year. Additionally ten kids of the following year were sampled and the serum copper levels were studied. Immediatly after parturition and 8 weeks later the dams showed low serum copper levels (10.4 +/- 11.1 micromol/l, 5.7 +/- 2.9 micromol/l resp.). At the end of the pasture season an increase of serum copper could be measured (19.3 +/- 16.0 micromol/l). To prevent enzootic ataxia due to congenital copper deficiency, the dams were treated with copper oxide wire particles in the next late gestation. At this time point serum copper concentrations started to decrease (18.5 +/- 8.4 micromol/l). The re-examination 3 month later demonstrated an increase of the serum mean copper concentrations up to 23.4 micromol/l in the dams and to 16.2 micromol/l in the kids. The serum copper levels were significantly higher compared to the levels the year before. Big variation of the serum copper levels in the control Boer goats occurred during the year, but no clinical symptoms of copper deficiency could be observed. The copper levels in the grass and soil samples were 6.8 mg/kg and 0.2 mg/kg dry substance, respectively. A secondary copper deficiency based on cadmium could be excluded through the low levels of soil samples. The contents of sulphur and molybdenum were not determined. The results indicate that the German Improved Fawn breed of goats suffered from a primary copper deficiency due to the inefficient mineral supplementation. The administration of Copinox in the last third of the gestation leads to a continious raising of the copper concentrations in the serum and is suited to prevent ataxia due to congential copper deficiency in neonatal kids. 相似文献
82.
Rehbein S Barth D Visser M Winter R Cramer LG Langholff WK 《Veterinary parasitology》2000,91(1-2):107-118
To evaluate the prophylactic and therapeutic effects of an ivermectin controlled-release capsule (IVM-CRC) on the productivity of growing sheep infested with Psoroptes ovis 24 male and 24 female Merino landrace lambs, 5-6 months old and weighing 21.2-35.0 kg, were used. Sixteen replicates of three animals were formed based on sex and Day 0 body weight. Within each replicate animals were randomly allocated to one of three groups: untreated control; IVM-CRC on Day 0; IVM-CRC on Day 84. For treatment an IVM-CRC for sheep weighing 20-45 kg was used which is designed to deliver ivermectin at a minimum dose of 20 microg/kg per day for 100 days. The lambs were infested with 50-60 P. ovis mites each on Days 14 and 21. Mites in skin scrapings were counted on Days 70, 84, 98, 112 and 126. Body weight and feed consumption were measured every 2 weeks from Day 0 to 126. The animals were slaughtered on Day 127 and their carcasses evaluated. The IVM-CRC treatment on Day 0 prevented the establishment of P. ovis. All untreated lambs became infested. The lambs treated with an IVM-CRC on Day 84 became mite-free from Day 112 onwards. The lambs treated on Day 0 had significantly (p<0.05) greater body weight gain from Day 0 to 84 (13.9 kg) and Day 0 to 126 (20.9 kg) than the untreated controls (9.6 and 12.8 kg, respectively) and the sheep treated on Day 84 (8.4 and 14.9 kg, respectively). Feed consumption (Days 0-126) for sheep treated with the IVM-CRC on Day 0 was higher than for sheep treated on Day 84 (p<0.05) and for the untreated controls (p<0.1). The carcasses of sheep treated with the IVM-CRC on Day 0 had significantly (p<0.05) higher warm and cold weights, carcass yield, rib eye area and back fat thickness than the untreated control group and the sheep treated with the IVM-CRC on Day 84. The sheep treated with the ivermectin CRC on either Day 0 or 84 had significantly (p<0.05) better muscle scores and lower muscle pH 1h post-slaughter than the untreated controls. There was no significant (p>0.1) difference between warm and cold carcass weights, carcass yield and rib eye area between sheep treated on Day 84 and untreated controls. 相似文献
83.
Volkmann N Amann KJ Stoilova-McPhie S Egile C Winter DC Hazelwood L Heuser JE Li R Pollard TD Hanein D 《Science (New York, N.Y.)》2001,293(5539):2456-2459
The seven-subunit Arp2/3 complex choreographs the formation of branched actin networks at the leading edge of migrating cells. When activated by Wiskott-Aldrich Syndrome protein (WASp), the Arp2/3 complex initiates actin filament branches from the sides of existing filaments. Electron cryomicroscopy and three-dimensional reconstruction of Acanthamoeba castellanii and Saccharomyces cerevisiae Arp2/3 complexes bound to the WASp carboxy-terminal domain reveal asymmetric, oblate ellipsoids. Image analysis of actin branches indicates that the complex binds the side of the mother filament, and Arp2 and Arp3 (for actin-related protein) are the first two subunits of the daughter filament. Comparison to the actin-free, WASp-activated complexes suggests that branch initiation involves large-scale structural rearrangements within Arp2/3. 相似文献
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87.
Kirsten E. Andersson Laura Adamovicz Lauren E. Mumm John M. Winter Gary Glowacki Rachel Teixeira-Neto Michael J. Adkesson Eric T. Hostnik Ellen Haynes Matthew C. Allender 《Journal of veterinary diagnostic investigation》2021,33(2):348
The spread of both infectious and noninfectious diseases through wildlife populations is of increasing concern. Neoplastic diseases are rarely associated with population-level impacts in wildlife; however, impacts on individual health can be severe and might reflect deteriorating environmental conditions. An adult male free-ranging Blanding’s turtle (Emydoidea blandingii) originally captured in 2005 and deemed healthy, was recaptured in 2018 with a 1 × 1.5 cm intra-oral broad-based right mandibular mass. An excisional biopsy was performed, and histopathology revealed squamous cell carcinoma (SCC). Consensus herpesvirus PCR identified a novel herpesvirus (proposed name Emydoidea herpesvirus 2 [EBHV-2]) within the tumor. EBHV-2 shares 85% sequence homology with Terrapene herpesvirus 2 (TerHV-2), a herpesvirus linked to fibropapillomas in eastern box turtles (Terrapene carolina carolina). Virus-associated fibropapillomas have been identified in multiple marine turtle species and have had debilitating effects on their populations, but to date, virus-associated SCCs are rarely reported. 相似文献
88.
Many tropical countries contain large numbers of species with small geographical ranges, here, for convenience, termed endemics. South America, for example, harbours 440 endemic land birds having ranges of less than 50 000 km2. These comprise about a quarter of the terrestrial avifauna of the continent. Such species are exceptionally vulnerable to deforestation and their preservation will require siting future parks or reserves in just the right places. Using Colombia and Ecuador as an illustration, we describe a simple procedure for locating areas of concentrated endemism that would be optimal for future protection. Unfortunately, there is little correspondence between the points of maximal endemism and the locations of existing and projected reserves in the two countries. The advantages and limitations of using satellite photos for habitat evaluation in centres of endemism are also discussed. 相似文献
89.
To test if locus-specific microsatellite markers designed for one genus are informative when used with related genera, the conservation of microsatellite-flanking intergeneric primer binding sites was tested in the closely related tribes Vicieae and Cicereae, from the subfamily Papilionoideae of the Leguminosae family. A total of 123 sequence-tagged microsatellite sites (STMS) markers derived from chickpea were used to amplify loci in lentil (Lens) and dry pea (Pisum). The percentage of chickpea primer binding sites conserved between the three genera was 54.4%. Hybridisation of 63 selected amplified loci to the digoxigenin-labelled oligonucleotide probe (TAA)5 showed that 69.8% of loci from dry pea and 66.6% of loci from lentil hybridised to the probe. Sequencing of amplified products from chickpea with the primer Ta176 demonstrated that one amplicon contained a microsatellite, whereas another amplicon amplified with the same particular STMS primer pair did not. Amplicons produced from lentil and pea with this primer pairs did not contain microsatellite sequences. Results obtained with Tr7, which amplified a PCR product in lentil and chickpea but not in pea, showed that microsatellite sequences were present in chickpea and absent in lentil. Similar results were obtained with Ts35, which produces amplicons in pea and chickpea; but, again, microsatellite sequences were only present in chickpea. We therefore conclude that STMS derived from chickpea could be used to detect variability between other Leguminosae genera, but it is necessary to verify whether homologous loci are revealed. 相似文献
90.
Teresa Millan Heather J. Clarke Kadambot H. M. Siddique Hutokshi K. Buhariwalla Pooran M. Gaur Jagdish Kumar Juan Gil Guenter Kahl Peter Winter 《Euphytica》2006,147(1-2):81-103
Summary Chickpea is a cool season grain legume of exceptionally high nutritive value and most versatile food use. It is mostly grown
under rain fed conditions in arid and semi-arid areas around the world. Despite growing demand and high yield potential, chickpea
yield is unstable and productivity is stagnant at unacceptably low levels. Major yield increases could be achieved by development
and use of cultivars that resist/tolerate abiotic and biotic stresses. In recent years the wide use of early maturing cultivars
that escape drought stress led to significant increases in chickpea productivity. In the Mediterranean region, yield could
be increased by shifting the sowing date from spring to winter. However, this is hampered by the sensitivity of the crop to
low temperatures and the fungal pathogen Ascochyta rabiei. Drought, pod borer (Helicoverpa spp.) and the fungus Fusarium oxysporum additionally reduce harvests there and in other parts of the world. Tolerance to rising salinity will be a future advantage
in many regions. Therefore, chickpea breeding focuses on increasing yield by pyramiding genes for resistance/tolerance to
the fungi, to pod borer, salinity, cold and drought into elite germplasm. Progress in breeding necessitates a better understanding
of the genetics underlying these traits. Marker-assisted selection (MAS) would allow a better targeting of the desired genes.
Genetic mapping in chickpea, for a long time hampered by the little variability in chickpea’s genome, is today facilitated
by highly polymorphic, co-dominant microsatellite-based markers. Their application for the genetic mapping of traits led to
inter-laboratory comparable maps. This paper reviews the current situation of chickpea genome mapping, tagging of genes for
ascochyta blight, fusarium wilt resistance and other traits, and requirements for MAS. Conventional breeding strategies to
tolerate/avoid drought and chilling effects at flowering time, essential for changing from spring to winter sowing, are described.
Recent approaches and future prospects for functional genomics of chickpea are discussed. 相似文献