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51.
OBJECTIVE: To determine features of an early fetal loss (EFL) syndrome and evaluate potential risk factors for EFL in Thoroughbred broodmares on 4 farms in central Kentucky. DESIGN: Retrospective study. ANIMALS: 288 pregnant broodmares. PROCEDURE: Year-2001 breeding records for 288 Thoroughbred broodmares were examined. Early fetal loss was defined as loss of a fetus that was viable at > or = 40 days of gestation but was subsequently lost by 5 months of gestation. RESULTS: Overall 2001 EFL rate was 25% (73/288), median gestational age at time of fetal loss was 77 days, and median date of loss was May 7. Mares on 1 farm had significantly fewer fetal losses (5%) than mares on the other 3 farms (26 to 35%). Fetal losses were higher for maiden (42%) and barren (42%) mares than for foaling mares (18%). Fetal losses were greater in young than in older mares. Effects of broodmare farm, mare age, and reproductive status were all significant. Fetal losses were not associated with sire used for mating or stud farm. CONCLUSIONS AND CLINICAL RELEVANCE: Greatest risk for EFL occurred during the period from late April to May (ie, in mares bred during February through March). Higher incidence of EFL in maiden and barren mares and lower incidence of EFL on 1 farm suggest management or environmental influences may have affected outcome. Risk factors that should be investigated include environmental differences among farms and differences in management procedures used for lactating versus nonlactating mares.  相似文献   
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IFN-alpha has been shown to induce both antiviral and antiproliferative activities in animals. This report describes the biological activity of five recently identified feline IFN-alpha subtypes expressed in the Chinese hamster ovary (CHO) cell line (rfeIFN-alpha1[CHO], rfeIFN-alpha2[CHO], rfeIFN-alpha3[CHO], rfeIFN-alpha5[CHO] and rfeIFN-alpha6[CHO]) and the feIFN-alpha6 subtype expressed in and purified from Pichia pastoris (rfeIFN-alpha6[P. pastoris]). The rfeIFN-alpha[CHO] subtypes were tested for antiviral activity against either Vesicular stomatitis virus (VSV) or feline calicivirus (FCV) infected feline embryonic fibroblast cell line (AH927) or Crandell feline kidney cell line (CRFK). Antiviral activity was induced against both VSV and FCV infected AH927 cells and VSV infected CRFK cells by all five of the rfeIFN-alpha[CHO] subtypes and rfeIFN-alpha6[P. pastoris]. In addition, the IFN-alpha inducible Mx gene (associated with antiviral activity) was upregulated in vivo 24 h following treatment with rfeIFN-alpha6[P. pastoris], compared to baseline levels seen prior to treatment. All of the rfeIFN-alpha[CHO] subtypes and rfeIFN-alpha6[P. pastoris] exhibited antiproliferative activity in the FeT-J cell line (an IL-2 independent feline T-cell line). Both necrosis and apoptosis were observed in rfeIFN-alpha6[P. pastoris]-treated FeT-J cells. The rfeIFN-alpha3[CHO] subtype consistently exhibited lower antiviral and antiproliferative activity compared to that observed with the other four rfeIFN-alpha[CHO] subtypes. In summary, this paper demonstrates that five previously described feIFN-alpha subtypes induce both antiviral and antiproliferative activities in vitro and are capable of upregulating the feMx gene in vivo.  相似文献   
54.
OBJECTIVE: To determine the effect of a porcine-derived small intestinal submucosa product (PSIS) on healing time, epithelialization, angiogenesis, contraction, and inflammation of wounds with exposed bone on the distal aspect of the limbs of dogs. STUDY DESIGN: Prospective, controlled, experimental study. ANIMAL POPULATION: 10 young adult, purpose-bred, male Beagles. METHODS: Small wounds with exposed bone were created on the lateral aspect of metatarsal V and the medial aspect of metatarsal II on both hindlimbs. Three sheets of PSIS were sutured into the wounds of the treated limb, and the other limb served as a control. On day 10, punch biopsies of the medial metatarsal wounds were collected and were evaluated microscopically after routine hematoxylin and eosin and phosphotungstic acid hematoxylin (PTAH) staining. The lateral metatarsal wounds were evaluated by planimetry and laser Doppler perfusion imaging on days 7, 14, and 21. Time until complete wound healing was also recorded. The level of significance was set at P < or =.05 for all statistical analyses. RESULTS: Laser Doppler perfusion measurements were significantly higher in control wounds on day 7, but no differences were noted on days 14 and 21. No significant differences in planimetric values, histopathologic appearance, or time until complete wound healing were noted among treated and control groups. CONCLUSIONS: No objective differences in healing were noted between control wounds and wounds treated with PSIS. CLINICAL RELEVANCE: There appears to be no contraindication to the use of PSIS on clean wounds with exposed bone on the distal limbs of dogs. However, our objective data provides no evidence that this product affects epithelialization, contraction, or time to complete healing in wounds with exposed bone.  相似文献   
55.
Between February 15 and May 17, 2011, a total of 88 broodmares (10 maiden, 10 barren, and 68 foaling) maintained on pasture in southeast Texas were examined three times weekly (Tuesday, Thursday, Saturday) by transrectal palpation and ultrasonography. On Tuesday or Thursday, mares in estrus with uterine edema, a relaxed cervix, and a dominant follicle ≥34 mm in diameter were alternately assigned to treatment with the following: group (1) 2,500-unit human chorionic gonadotropin (hCG), intravenous; group (2) 1.0-mg BioRelease Histrelin (Biorelease Technologies, Lexington, KY), intramuscular; or group (3) 0.5-mg BioRelease Histrelin, intramuscular. Ovulation was confirmed by ultrasonographic examination. The percentage of mares ovulating within 2 days appeared to be similar between maiden, barren, and foaling mares, so responses for all mares were totaled for analysis. A nonsignificant trend for higher ovulation rates within 2 days was noted for both dose rates of histrelin compared with hCG treatment (31/37, 84%; 34/37, 92%; and 33/36, 92% for groups 1-3, respectively) (P = .45). Ovulatory responses appeared to improve for both products as the season progressed, yet no differences were detected between response rates to histrelin or hCG for any month (P ≥ .50). The use of 1.0- or 0.5-mg BioRelease Histrelin was found to be at least equally effective as hCG treatment for inducing ovulation within 2 days of treatment throughout the breeding season.  相似文献   
56.
Soil water repellency can limit postfire reseeding efforts and thus increase the susceptibility of a site to weed invasion. We evaluated the effectiveness of wetting agents and simulated anchor chaining for improving seedling growth and survival in water-repellent soil, for the native perennial bluebunch wheatgrass (Pseudoroegneria spicata) and invasive annual cheatgrass (Bromus tectorum). Research was performed in a glasshouse, on 20-cm-diameter soil cores that were excavated from underneath burned Utah juniper (Juniperus osteosperma) trees. The experiment was arranged as a randomized split-plot design, with the two grass species sown separately under four soil treatments: 1) no treatment (control), 2) simulated anchor chaining (hereafter referred to as “till”), 3) wetting agent, and 4) till plus wetting agent. Soil water content was highest in the wetting agent treatment, lower for till, and lowest in the control. Overall, the response of bluebunch wheatgrass and cheatgrass was similar among treatments. At the conclusion of the study, wetting agent cores had twice as many seedlings as the control, while the till and control were similar. Despite a lower number of seedlings, tilling in general resulted in the same level of biomass as the wetting agent treatment. Overall, biomass in the till and wetting agent treatments was at least twofold higher than the control. No benefit was found in applying both till and wetting agent treatments together in comparison to just applying wetting agent. Because of a lack of correlation between glasshouse and field settings the results of this study need to be interpreted with caution. Our data may indicate that if cheatgrass is not already present on the site, anchor chaining or treating the soil with wetting agent can increase establishment of seeded species.  相似文献   
57.
OBJECTIVE: To evaluate the quality of information regarding osteoarthritis (OA) in dogs currently available on the World Wide Web. DESIGN: Survey study. PROCEDURE: 5 search engines were searched with the keywords "dog," "degenerative joint disease," "canine," and "osteoarthritis," and the first 50 sites listed by each search engine were analyzed. Unique Web site addresses were distributed to 3 diplomates of the American College of Veterinary Surgeons, who provided a standardized evaluation of each site. RESULTS: 30 unique Web sites were evaluated. Twenty (66%) provided information consistent with conventional knowledge as outlined in textbooks and peer-reviewed literature, 8 (27%) provided experimental or anecdotal information in addition to conventional knowledge, and 2 (7%) provided misleading information. Mean scores for overall usefulness of the information provided in regard to clinical features of and treatment for OA were 1.3 and 1.5, respectively (1 = information of minimal use; 5 = very useful information). Twenty-three (77%) sites encouraged pet owners to seek the advice of a veterinarian. Twenty-three (77%) sites were given overall quality scores < 2, and 7 (23%) were given scores between 2 and 3 (1 = site was counterproductive; 5 = site was very valuable). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that the quality of information currently available on the Web that addresses OA in dogs is questionable. Although most of the sites conveyed some conventional information with reasonable accuracy, the information was incomplete, of minimal use, and often considered counterproductive.  相似文献   
58.
Sammy  Ramirez  DVM  MS  Steven A.  Sedrish  DVM  MS  Dale L.  Paccamonti  DVM  MS  Dennis D.  French  DVM  MS 《Veterinary radiology & ultrasound》1999,40(2):165-168
This report describes two mares presented for evaluation of anorexia, fever of unknown origin, and weight loss. Clinical examination, laboratory findings, and transrectal ultrasonographic images suggested ovarian abscessation. One mare was successfully treated medically. Because of financial considerations, the second mare was euthanatized and a postmortem examination was performed. At necropsy, there was an enlarged right ovary with an adhesion to the large colon. Microscopic findings were characteristic of an ovarian abscess.  相似文献   
59.
The study objective was to determine the effects of feeding food enriched in antioxidants and a program of environmental/cognitive enrichment on selected ex vivo assays of inflammatory and immune cells in healthy geriatric Beagle dogs (n=21). Four groups of dogs were tested using a 2 x 2 factorial design. The 2-year longitudinal study included both nutritional (control food or antioxidant-fortified food) and behavioral (normal level or cognitive enrichment) interventions. Behavior enrichment included increased exercise, environmental enrichment, and a series of learning tasks. Phagocytosis of opsonized latex-coated beads by peripheral blood neutrophils was measured by flow cytometry and found to be significantly increased in dogs receiving both dietary antioxidants and cognitive enrichment. Simultaneous stimulation of cells with Con A and suppression with Dex resulted in decreased lymphocyte proliferation in dogs receiving both dietary antioxidants and cognitive enrichment, compared to dogs receiving dietary antioxidants or cognitive enrichment alone. There were no significant differences between the groups of dogs for percentages of CD4 and CD8 T-lymphocyte subpopulations before or after lymphocyte stimulation with Con A. These results support our hypothesis that both dietary antioxidants and behavioral enrichment enhance host defense mechanisms.  相似文献   
60.
对Ⅱ型猪圆环病毒的研究为与猪断奶后多系统消耗性综合征在全球爆发有关的问题提供了大量答案,但还有一些方面迫切需要引起人们的关注,以便为可能出现的梦魇般的前景准备对策.  相似文献   
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