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1.
Cooling stored epididymal samples for several days allows facilities to transport and process genetic material post‐mortem. Improvements to this practice allow the preservation of sperm from domestic cats, which are the ideal study model for wild felids. However, the modifications in spermatic features and the oxidative profile are not fully understood in cats. This information is necessary for the development of biotechniques, such as new extenders for cryopreservation. Therefore, the purpose of this study was to evaluate the spermatic and oxidative profile in samples from the epididymal cauda of domestic cats cooled at 5°C for 24, 48 and 72 hr. Spermatozoa were collected from the epididymis cauda. Evaluations consisted of computer‐assisted sperm analysis (CASA), plasma membrane integrity (eosin/nigrosin), acrosome integrity (fast green/rose bengal), sperm morphology, sperm DNA integrity (toluidine blue), mitochondrial activity (3′3 diaminobenzidine), activity of the antioxidant enzymes glutathione peroxidase (GPx) and superoxide dismutase (SOD), measurement of lipid peroxidation (TBARS) and protein oxidation. A decrease in sperm motility parameters was observed after 72 hr of cooling (i.e. total and progressive) with a higher percentage of minor (37.7 ± 6.3%) and total defects (53.4 ± 6.3%). Additionally, a decrease in high mitochondrial activity (Class I: 16.6 ± 2.2%) occurred after 72 hr. The decrease in motility rates after a long cooling time probably was caused by the increase in sperm abnormalities. A long cooling time causes cold shock and mitochondrial exhaustion, but there was no observed change with the oxidative stress condition. Therefore, cat epididymal sperm stored at 5°C appear to maintain a high quality for up to 48 hr of cooling time.  相似文献   
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Artificial breeding of mithun poses several challenges including lack of standard protocol for cryopreservation of spermatozoa. This is further complicated by harmful effects of hen's egg yolk (EY) as additive in extender. Purified low‐density lipoproteins (LDL) extracted from EY have been shown as beneficial over EY extender for long‐term semen storage in several species. This investigation explored use of LDL versus EY on semen quality and oxidative stress following freezing–thawing of spermatozoa. A total of 25 of 50 ejaculates based on biophysical parameters were selected for the experiment. After diluting with the Tris‐citrate‐glycerol (TCG) extender, each sample was split into three equal aliquots: Group I, control, EY; Group II and Group III contained 8% and 10% purified LDL, respectively. Frozen–thawed samples were evaluated for motility parameters (progressive, and in the bovine cervical mucus penetration test [BCMPT]), viability, sperm and nuclear abnormality, acrosome integrity, and enzymatic (leakage of intracellular contents) and biochemical (oxidative stress) profiles and in vitro fertility (IVF) assay. Study revealed a significant (< .05) improvement in viability, sperm and nuclear abnormality, acrosome integrity, motility (progressive and in cervical mucus), cholesterol content, and reduction in the leakage of intracellular enzymes in Group II. Moreover, intactness of acrosome and biochemical membranes was protected significantly (p < .05) in addition to significant (p < .05) improvement in binding per cent and binding index in IVF assay in extender containing 8% LDL. These results demonstrate that although cryopreservation of mithun's spermatozoa in EY was comparable with other species, addition of 8% LDL holds a clear advantage over EY or 10% LDL.  相似文献   
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This study describes seroprevalence of Peste des petits ruminants (PPR) in cattle and buffaloes carried out during the period 2009–2010 using the randomly collected serum samples from different parts of Southern peninsular India. The report presents the results of PPR virus (PPRV)—specific antibodies in situations where either the subclinical or inapparent or non-lethal infection was there in cattle and buffaloes. A total of 2,548 serum samples [cattle = 1,158, buffaloes = 1,001, sheep = 303 and goat = 86] were collected and screened for PPRV antibodies by using a PPR monoclonal antibody-based competitive ELISA kit. Analysis of 2,159 serum samples indicates an overall 4.58% prevalence of PPRV antibody in cattle and buffaloes. The presence of PPRV-specific antibodies demonstrates that cattle and buffaloes are exposed to PPR infection naturally, and the transmission mode may be direct or indirect. Further, it implies the importance of bovines as subclinical hosts for the virus besides widespread presence of the disease in sheep and goats in the country.  相似文献   
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In cattle, Ureaplasma diversum has been associated with decreased fertility, granular vulvovaginitis, endometritis, salpingitis and spontaneous abortion in cows and seminal vesiculitis, balanoposthitis and changes in bull sperm. The presence of U. diversum within the Australian cattle population has not been established. One of the aims of this study was to determine if U. diversum was present in Australian cattle, using culture and polymerase chain reaction (PCR), both of which are considered to be gold standards for bacterial identification. Of 100 samples collected from 66 male and 34 female cattle, 15 were positive for U. diversum. Therefore, Australia can no longer be considered free of U. diversum. Further studies should be conducted to ascertain the effects of U. diversum within Australian cattle herds and, if warranted, to investigate prevention, treatment and eradication protocols.  相似文献   
5.
The spatially dependent de-excitation of a beam of metastable argon atoms, traveling through an optical standing wave, produced a periodic array of localized metastable atoms with position and momentum spreads approaching the limit stated by the Heisenberg uncertainty principle. Silicon and silicon dioxide substrates placed in the path of the atom beam were patterned by the metastable atoms. The de-excitation of metastable atoms upon collision with the surface promoted the deposition of a carbonaceous film from a vapor-phase hydrocarbon precursor. The resulting patterns were imaged both directly and after chemical etching. Thus, quantum-mechanical steady-state atom distributions can be used for sub-0.1-micrometer lithography.  相似文献   
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Abstract

We developed a procedure for preparing a model for mapping spatially distributed zones of aphid pest (Lipaphis erysimi) outbreaks at a regional level. This study employed near-surface meteorological parameters derived from National Oceanic and Atmospheric Administration (NOAA) Television and Infra-Red Operational Satellites (TIROS) Operational Vertical Sounder (TOVS) data and field observations of disease infestation. The study area comprised three sites representing semi-arid and sub-humid regions of dominant Indian mustard (Brassica juncea L.)-growing regions of India. A model based on TOVS-derived cumulative surface air temperature and minimum specific humidity (SpH) was developed to estimate the date of ‘aphid onset’ (first appearance), date of peak infestation and location of severity with respect to aphid population density. Aphid population growth rate during the linear growth phase between aphid onset to peak was computed using SpH-weighted temperature and dates of sowing of the crop (crop age). Sowing dates of mustard crop, of northwest India, were obtained from spectral growth profiles derived from time series remote sensing (RS) products of the SPOT-4 VEGETATION sensor. Estimated dates of peak aphid infestation and peak population showed a strong match with the observed data. The location of peak aphid population density was depicted in each spatial grid of 25×25 km2 for parts of northwest India. The simulated aphid population build-up and date of peak population density was validated with observed data for an unknown site in the Sriganganager district, Rajasthan state, India. Comparison of predicted dates of attaining peak aphid population with observations showed a deviation of ±7 days. After validation, the regional level model was applied over a large area of a mustard-growing region for varying dates of sowing, surface air temperature and specific humidity, to show the spatial distribution of aphid growing severity zones (population density) and to predict dates of severe aphid infestation (peak population) at each grid level in the region.  相似文献   
10.
Prevalence of peste des petits ruminants among sheep and goats in India   总被引:1,自引:0,他引:1  
This study measured the clinical prevalence of peste des petits ruminants (PPR) among sheep and goats in India between 2003 and 2009 by analyzing clinical samples from suspected cases of PPR that were submitted to the Rinderpest and Allied Disease Laboratory, Division of Virology, IVRI, Mukteswar for PPR diagnosis. PPR outbreaks were confirmed by detecting PPR virus (PPRV)-specific antigen in the clinical samples. Clinical samples (blood, nasal swabs, spleen, lymph node, kidney, liver, intestine, and pooled tissue materials) were taken from a total of 592 sheep and 912 goats in different states of India and screened for the presence of PPRV antigen using a monoclonal antibody-based sandwich ELISA kit. A total of 20, 38, and 11 laboratory-confirmed PPR outbreaks occurred among sheep, goat, and combined sheep and goat populations, respectively. Our findings provide evidence of widespread PPR endemicity in India. The underlying reasons could be variations in husbandry practices in different geographical regions, agro-climatic conditions, and livestock migration. Furthermore, decrease in the number of PPR outbreaks over time might be due to the effectiveness of current live PPR vaccines and timely vaccination of target species. Vaccination against PPR has been practiced in India since 2002 to control this disease.  相似文献   
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