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31.
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Two 12-week-old Tippler pigeons were evaluated for ocular abnormalities associated with congenital blindness. The pigeons were emaciated and blind. Biomicroscopy and direct and indirect ophthalmoscopy findings of the Tippler pigeons were normal with the exception of partially dilated pupils at rest. Scotopic (blue stimuli) and photopic monocular electroretinograms were extinguished in the blind Tippler pigeons. Histological and electron microscopy studies revealed reduced numbers of rods and cones, and an absence of the double cone complex. The photoreceptor cells' outer segments were absent, and the inner segments were short and broad. The number of cell nuclei in the outer and inner nuclear layers was decreased, and the internal and external plexiform layers were reduced in width. Photoreceptor cell endfeet with developing synaptic ribbons were present in the external plexiform layer. Inflammatory cell and subretinal debris was not seen. The electroretinographic, histopathological, and ultrastructural findings of the blind Tippler pigeons support the diagnosis of a photoreceptor cell dysplasia. 相似文献
33.
Martella V Cirone F Elia G Lorusso E Decaro N Campolo M Desario C Lucente MS Bellacicco AL Blixenkrone-Møller M Carmichael LE Buonavoglia C 《Veterinary microbiology》2006,116(4):301-309
Canine distemper virus (CDV) is a highly contagious viral pathogen causing lethal disease in dogs and other mammalians. A high degree of genetic variation is found between recent CDV strains and the old CDV isolates used in the vaccines and such genetic variation is regarded as a possible cause of the increasing number of CDV-related diseases in dogs. The H gene shows the greatest extent of genetic variation that allows for distinction of various lineages, according to a geographical pattern of distribution and irrespective of the species of identification. In the present study, hemagglutinin (H) genes obtained from field strains detected from clinical specimens of Italian dogs were analyzed genetically. Phylogenetic analysis revealed that a homogeneous group of CDV strains is widespread in Italian dogs, all which are included into the European lineage. Unexpectedly, strains 179/04 and 48/05 clustered along with CDVs of the Arctic lineage, the highest identity being to strain GR88 (98.0 and 98.4%aa, respectively). The full-length sequence of a red fox CDV strain, 207/00 was also determined and analyzed. The H protein of the fox CDV strain was unrelated to strains within the major European lineage. These results suggest that at least three different CDV lineages are present in Italy. 相似文献
34.
Globoid cell leukodystrophy (GLD), or Krabbe's disease, is a progressive autosomal recessive disorder of the central nervous system in man and in various other species. GLD has been shown to result from various mutations in the gene encoding galactocerebrosidase (GALC), a lysosomal enzyme. We investigated the molecular basis of GLD in a related group of Irish setters. Sequencing of the GALC cDNA from an affected individual revealed an insertion mutation of 78 base pairs (bp) consisting of 16 bp of insertion site duplication and 62 bp of sequence derived from the U4 small nuclear RNA. We implemented a PCR-based test which is useful for identifying carriers of the mutation. 相似文献
35.
G Elamaran KP Singh MK Singh SK Singla MS Chauhan RS Manik P Palta 《Reproduction in domestic animals》2012,47(6):1027-1036
This study examined the effects of O2 concentration (5% vs 20%) during in vitro maturation (IVM), fertilization (IVF) and culture (IVC) or supplementation of IVM and IVC media with cysteamine (50 and 100 μm , respectively; IVM, IVF and IVC carried out in 20% O2), on blastocyst rate and relative mRNA abundance of some apoptosis‐related genes measured by real‐time qPCR in immature and in vitro‐matured buffalo oocytes and in embryos at 2‐, 4‐, 8‐ to 16‐cell, morula and blastocyst stages. The blastocyst rate was significantly higher (p < 0.05) while the percentage of TUNEL‐positive cells was significantly lower (p < 0.05) under 5% O2 than that under 20% O2. The mRNA expression of anti‐apoptotic genes BCL‐2 and MCL‐1 was significantly higher (p < 0.05) and that of pro‐apoptotic genes BAX and BID was lower (p < 0.05) under 5% O2 than that under 20% O2 concentration at many embryonic stages. Following cysteamine supplementation, the blastocyst rate and the relative mRNA abundance of BCL‐XL and MCL‐1 was significantly higher (p < 0.05) and that of BAX but not BID was lower (p < 0.05) at many stages of embryonic development, although it did not affect the percentage of TUNEL positive cells in the blastocysts significantly. The mRNA expression pattern of these genes during embryonic development was different in 5% vs 20% O2 groups and in cysteamine supplemented vs controls. At the 8‐ to 16‐cell stage, where developmental block occurs in buffalo, the relative mRNA abundance of BCL‐2 and MCL‐1 was highest under 5% O2 concentration and that of BAX and BID was highest (p < 0.05) under 20% O2 concentration. These results suggest that one of the mechanisms through which beneficial effects of low O2 concentration and cysteamine supplementation are mediated during in vitro embryo production is through an increase in the expression of anti‐apoptotic and a decrease in the expression of pro‐apoptotic genes. 相似文献
36.
37.
Martella V Elia G Lucente MS Decaro N Lorusso E Banyai K Blixenkrone-Møller M Lan NT Yamaguchi R Cirone F Carmichael LE Buonavoglia C 《Veterinary microbiology》2007,122(1-2):32-42
CDV is a highly contagious viral pathogen causing a lethal systemic disease in dogs and other carnivores. Several lineages or genotypes of CDV exist that are variously distributed throughout several continents. Legal or uncontrolled trading of animals may modify the epidemiology of CDV, introducing novel strains in CDV-na?ve areas or accounting for the resurgence of CDV in areas where vaccine prophylaxis was effective and successful to control the disease. A hemi-nested PCR system was developed to genotype strains of the major CDV lineages, America-1, Europe, Asia-1, Asia-2 and Arctic. The assay was tested using a collection of 27 laboratory and vaccine strains and of 36 field CDV strains. Distinct lineages could be differentiated by specific primers targeted to the H gene. The method could be useful for molecular epidemiological studies of CDV, providing a tool for large-scale studies, and for the diagnosis of vaccine-related disease. 相似文献
38.
V Vescoli L Degiorgi W Henderson G Gruner KP Starkey LK Montgomery 《Science (New York, N.Y.)》1998,281(5380):1181-1184
Optical experiments were conducted on a series of organic linear chain conductors with different values of the interchain single-electron transfer integral tb, which quantifies the degree of anisotropy. Electron-electron interactions together with Umklapp scattering resulted in a correlation gap and an insulating state for small tb. An insulator-to-metal transition was observed when tb exceeded a critical value, on the order of the correlation gap Egap. The absence of a plasma edge on the insulator side of the transition for polarization perpendicular to the chains suggests that the electrons are confined to the chains. The optical features of the metallic state, when contrasted with the magnetic properties, are suggestive of spin-charge separation. 相似文献
39.
40.
MSD Marley MD Givens PK Galik KP Riddell DA Stringfellow 《Reproduction in domestic animals》2009,44(3):532-535
The purpose of this study was to determine whether or not embryos derived from in vitro fertilization of oocytes from persistently infected (PI) cattle would contain infectious virus. Three in vitro embryo production treatment groups were assessed: 1) oocytes and uterine tubal cells (UTC) free of bovine viral diarrhoea virus (BVDV) (negative control), 2) oocytes free of BVDV fertilized and cultured in media containing UTC obtained from PI heifers, and 3) oocytes from PI heifers fertilized and cultured in media containing UTC free of BVDV. The developmental media, UTC and embryos (individual or groups of five) were assayed for virus. Virus was not isolated from any samples in treatment group 1. As shown in previous studies, a proportion of embryo samples were positive for BVDV in treatment group 2. In treatment group 3, the virus associated with the oocytes contaminated the developmental media and infected susceptible co-culture cells used during fertilization and culture. In addition, 65% (11/17) of the degenerated ova from treatment group 3 had infectious virus associated with them. While none of the ova developed into transferable embryos, the study did confirm that use of oocytes from PI cows could lead to amplification of BVDV and cross contamination during in vitro embryo production. 相似文献