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101.
An inherited form of progressive retinal atrophy (PRA) is recognized in Persian cats; however, the prevalence of PRA in the breed has not been determined. Breeders suggest that cats from only brown ('chocolate') or Himalayan ('pointed') lines are at risk for PRA, suggesting the disease is not widespread. This study was designed to evaluate whether PRA in Persian cats is associated with three coat colors, including chocolate, or with a highly prevalent inherited disease in this breed--polycystic kidney disease (PKD). Sixty related cats were evaluated for PRA by ophthalmic examination and genetically typed for PKD and the mutations that cause coat color variants in agouti, brown and color (producing the pointed coloration in Himalayan). No associations were identified among any of the traits, including between PRA and chocolate. These data suggest that PRA is not limited to cats with chocolate coat coloration and breeders and veterinarians should be aware that the prevalence of the disease may be higher than currently claimed.  相似文献   
102.
The objectives of this investigation were to understand transplacental transport of iron by secreted uteroferrin (UF) and haemophagous areas of water buffalo placenta and clarify the role(s) of blood extravasation at the placental‐maternal interface. Placentomes and interplacentomal region of 51 placentae at various stages of gestation were fixed, processed for light and transmission electron microscopy, histochemistry and immunohistochemistry. Haemophagous areas were present in placentomes collected between 4 and 10 months of pregnancy. Perl’s reaction for ferric iron was negative in placentomes, but positive in endometrial glands. Positive staining for UF indicated areas in which it was being taken up by phagocytosis and/or fluid phase pinocytosis in areolae of the interplacentomal mesenchyme, with little staining in endometrial stroma. Imunohistochemistry detected UF in trophectoderm of haemophagous regions of placentomes and in other parts of the foetal villous tree, but the strongest immunostaining was in the epithelial cells and lumen of uterine glands. Ultrastructural analyses indicated that erythrophagocytosis was occurring and that erythrocytes were present inside cells of the chorion that also contained endocytic vesicles and caveolae. Results of this study indicate that both the haemophagous areas of placentomes and the areolae at the interface between chorion and endometrial glands are important sites for iron transfer from mother to foetal‐placental tissues in buffalo throughout pregnancy.  相似文献   
103.
Grasslands of the Edwards Plateau of central Texas have been extensively altered through woody species encroachment, particularly as a result of increasing abundance of the invasive native shrub, Ashe juniper (Juniperus ashei). Over the last several decades there has been widespread mechanical removal of the species. The wood is often left in place to decompose, either mulched or not. Where the wood is left to decompose might have some bearing on its rate of decomposition. This study was conducted to determine the rates of Ashe juniper wood decomposition as a function of open vs. shaded habitat and the potential effect of wood decomposition on nutrient inputs into this system. Wood decomposition in this arid ecosystem might be expected to occur more rapidly in shaded habitat where the moisture and temperature regimes would be more favorable for wood-decomposing fungi. On the other hand, during times of low rainfall we might expect wood to decompose more rapidly when exposed to high levels of ultraviolet radiation. In our experiment, we found no difference between open and shaded treatments. Wood biomass loss occurred rapidly over the first 3–4 mo of the study and slowed for the remaining 2 yr. Wood carbon (C) increased only slightly (7.3%), but nitrogen (N) increased significantly (176%). As a consequence of changes in wood nitrogen, C∶N decreased through time. Results of this study suggest that the wood decomposition process in open and shaded habitats in this arid ecosystem during a time of low rainfall do not differ. Our findings also suggest that land managers aiming to establish native species following felling of Ashe juniper should do so in the first year when nutrient release from decomposing wood is the highest.  相似文献   
104.
In some regions of the world, where the bioavailability of selenium (Se) in soil is low and/or declining (e.g., due to use of high-sulfur fertilizers), there is increased risk of adverse affects on animals and human health. In recent years, increased research attention has focused on understanding the relationships between Se contents in foods and supplements and their nutritional benefits for animal and humans. The objective of this study was to use a species-unspecific isotope dilution and reverse phase ion pairing-inductively coupled plasma-mass spectrometry techniques for the identification and quantification of Se species in biofortified grains (i.e., wheat and triticale), flour, and wheat biscuits. The information on Se species was used to gain an understanding of the bioavailability of Se in biofortified and process-fortified wheat biscuits used in a clinical trail. The major Se species identified in biofortified and process-fortified samples were selenomethionine (76-85%) and selenomethionine selenoxide (51-60%), respectively. Total plasma Se concentrations in the biofortified Se exposure group were found to increase throughout the 6 month trial period (mean=122 microg L(-1) at 0 months to 194 microg L(-1) at 6 months). In contrast, the trial group exposed to process-fortified Se biscuits showed little increase in mean total Se plasma concentrations until 4 months of exposure (mean=122 microg L(-1) at 0 months to 140 microg L(-1) at 4 months) that remained constant until the end of the trial period (mean=140 microg L(-1) at 4 months to 138 microg L(-1) at 6 months). The difference in total Se plasma concentrations may be due to the presence and bioavailability of different Se species in biofortified and process-fortified biscuits. An understanding of Se speciation in foods enables better understanding of pathways and their potential benefits for animals and humans.  相似文献   
105.
State‐of‐the‐art health care includes genome sequencing of the patient to identify genetic variants that contribute to either the cause of their malady or variants that can be targeted to improve treatment. The goal was to introduce state‐of‐the‐art health care to cats using genomics and a precision medicine approach. To test the feasibility of a precision medicine approach in domestic cats, a single cat that presented to the University of Missouri, Veterinary Health Center with an undiagnosed neurologic disease was whole‐genome sequenced. The DNA variants from the cat were compared to the DNA variant database produced by the 99 Lives Cat Genome Sequencing Consortium. Approximately 25× genomic coverage was produced for the cat. A predicted p.H441P missense mutation was identified in NPC1, the gene causing Niemann‐Pick type C1 on cat chromosome D3.47456793 caused by an adenine‐to‐cytosine transversion, c.1322A>C. The cat was homozygous for the variant. The variant was not identified in any other 73 domestic and 9 wild felids in the sequence database or 190 additionally genotyped cats of various breeds. The successful effort suggested precision medicine is feasible for cats and other undiagnosed cats may benefit from a genomic analysis approach. The 99 Lives DNA variant database was sufficient but would benefit from additional cat sequences. Other cats with the mutation may be identified and could be introduced as a new biomedical model for NPC1. A genetic test could eliminate the disease variant from the population.  相似文献   
106.
A total of 89 Thoroughbreds, 14 to 333 days old (born in 1982), were examined at necropsy for certain internal parasites during a 1-year-period, Mar 1, 1982, to Feb 28, 1983. The eyes of 73 of the horses and the cranial mesenteric arteries of 71 were examined. Specific interest was on prevalence of parasites according to month of the year and age of the horses at necropsy. Parasites recovered (first month-last month infected horse found) were as follows: Thelazia lacrymalis (eyes) immature and mature (June - February); Habronema/Draschia (lungs) immature (May - September); Habronema muscae (stomach) immature (July - February) and mature (September - February); Draschia megastoma (stomach) immature (August - December), mature (August - February), and lesions (September - February); Gasterophilus intestinalis (stomach) 2nd instars (July - February) and 3rd instars (August - February); Gasterophilus nasalis (stomach) 2nd instars (August - November) and 3rd instars (August - February); Parascaris equorum (lungs) immature (March - November), P equorum (small intestine) immature (March - February), and mature (July - February); Strongyloides westeri (small intestine) mature (March - September); Anoplocephala perfoliata (cecum) immature and mature (August - February); Strongylus vulgaris (cranial mesenteric artery) immature and mature (May - February). Other parasites recovered, but only from 1 or 2 horses each (months found in infected horses) were: Thelazia skrjabini (eyes) (October), Dictyocaulus arnfieldi (lungs) (January); Trichostrongylus axei (stomach) (October); Anoplocephala magna (small intestine) (October, November); S vulgaris (cecum) (November); Strongylus edentatus (cecum) (January); Setaria spp (abdominal cavity) (January). Influence of probable chemotherapy of the horses on prevalence of the parasites is discussed.  相似文献   
107.
Prevalence of natural infections of parasites from the lungs of 488 dead Thoroughbreds in Kentucky was investigated. The horses varied from 1 to 32 years of age; 419 horses were from 215 farms and 69 horses were from 68 individual sources for which a specific farm was not identified. Examinations of the lungs were made from Mar 1, 1983 through Feb 29, 1984. Dictyocaulus arnfieldi was recovered from 56 (11%) of the horses. Other parasites found were larvae of Parascaris equorum in 37 (8%) and of Habronema/Draschia in 67 (14%) of the horses. The possible effect of ivermectin treatment on the prevalence of D arnfieldi in the lungs is discussed. Presence of D arnfieldi in 20 other selected dead equids was also investigated.  相似文献   
108.
The effect of fungi on the growth of body organs in mice was investigated. Single, intraperitoneal injections of yeasts (Cryptococcus albidus, Saccharomyces cerevisiae, Schizosaccharomyces octosporus) or molds (Aspergillus niger, Geotrichum candidum, Mucor haemalis) induced an increase in the mass of seminal vesicles and coagulating glands independent of whole body weight changes in mice.  相似文献   
109.
Tritrichomonas foetus (T. foetus) is the causative agent of bovine trichomonosis, a sexually transmitted disease leading to abortion (from 1 to 8 months gestation), infertility, and occasional pyometra. The annual losses to the U.S. beef industry are estimated to be in the hundreds of millions of dollars. Currently, the "gold standard" diagnostic test for trichomonosis in most countries is the cultivation of live organisms from reproductive secretions. The cultured organisms can then be followed by PCR assays with primers that amplify T. foetus to the exclusion of all other trichomonad species. Thus, negative results present as null data, indistinguishable from failed PCR amplification during T. foetus specific amplification. Our newly developed assay improves previously developed PCR based techniques by using diagnostic size variants from within the internal transcribed spacer 1 (ITS1) region that is between the 18S rRNA and 5.8S rRNA subunits. This new PCR assay amplifies trichomonad DNA from a variety of genera and positively identifies the causative agent in the bovine trichomonad infection. This approach eliminates false negatives found in some current assays as well as identifying the causative agent of trichomonad infection. Additionally, our assay incorporates a fluorescently labeled primer enabling high sensitivity and rapid assessment of the specific trichomonad species. Moreover, electrophoretic separation of amplified samples can be outsourced, thus eliminating the need for diagnostic laboratories to purchase expensive analysis equipment.  相似文献   
110.
The use of the fungicides benomyl and thiophanate-methyl on experimental orchard plots for 3 years and of benomyl on a commercial orchard for 1 year resulted in a drastic reduction of earthworm populations. The species of earthworms affected were Lumbricus terrestris, L. castaneus, L. festivus, L. rubellus, Allolobophora caliginosa, A. chlorotica, A., longa, A. rosea, A. tuberculata and Octolasium cyaneum. L. terrestris and A. chlorotica were more affected than the other species, both being virtually eliminated after 2 years' spraying. The depleted populations of species other than L. terrestris and A. chlorotica recovered to normal levels after a 2-year rest period following a single year's treatment with benomyl (1.40 kg/ha). The role of the surface-feeding L. terrestris is discussed in relation to the spray fall-out on the sward and to grass management.  相似文献   
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