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71.
Declercq J 《Veterinary dermatology》2004,15(1):42-46
Abstract An alopecia and dermatopathy following pelvic fractures associated with vehicular trauma is reported in three cats. The animals presented 3–4 weeks post injury with acute hair loss, glistening appearance of the skin and erosions involving the lower back. Histological examination revealed atrophy of the hair follicles and adnexal structures and follicular telogenization, dermal fibroplasia and mild lymphocytic infiltrate, fibroplasia and inflammation in the panniculus. Vascular damage secondary to the external trauma to blood vessels supplying the skin over the lumbar region and subsequent ischaemia may represent the pathomechanism of this type of alopecia. Focal permanent hair loss can be expected. 相似文献
72.
73.
Hayley Weston Murphy Michele Miller Jan Ramer Dominic Travis Robyn Barbiers Nathan D Wolfe William M Switzer 《Journal of zoo and wildlife medicine》2006,37(3):219-233
Nonhuman primates can be naturally infected with a plethora of viruses with zoonotic potential, including retroviruses. These simian viruses present risks to both captive nonhuman primate populations and persons exposed to nonhuman primates. Simian retroviruses, including simian immunodeficiency virus, simian type D retrovirus, simian T-lymphotropic virus, and gibbon ape leukemia virus, have been shown to cause clinical disease in nonhuman primates. In contrast, simian foamy virus, a retrovirus that is highly prevalent in most nonhuman primates, has not been associated with clinical disease in naturally infected primates. Although it has been shown that human retrovirus infections with human T-lymphotropic virus and human immunodeficiency virus originated through multiple independent introductions of simian retroviruses into human populations that then spread globally, little is known about the frequency of such zoonotic events. In this article, exogenous simian retroviruses are reviewed as a concern for zoo and wildlife veterinarians, primate handlers, other persons in direct contact with nonhuman primates, and other nonhuman primates in a collection. The health implications for individual animals as well as managed populations in zoos and research institutions are discussed, the cross-species transmission and zoonotic disease potential of simian retroviruses are described, and suggestions for working safely with nonhuman primates are provided. 相似文献
74.
Effect of lameness on milk yield in dairy cows 总被引:1,自引:0,他引:1
Hernandez J Shearer JK Webb DW 《Journal of the American Veterinary Medical Association》2002,220(5):640-644
OBJECTIVE: To examine the relationship between lameness and milk yield in dairy cows. DESIGN: Cohort study. ANIMALS: 531 dairy cows. PROCEDURE: Cows affected with lameness were classified into 1 of 3 groups on the basis of type of diseases or lesions observed, including interdigital phlegmon (foot rot), papillomatous digital dermatitis (foot warts), or claw lesions. Cows not affected with lameness were classified as healthy. From Dairy Herd Improvement Association records, 305-day mature equivalent milk yield data were collected at the end of lactation or when the cow left the herd. Milk yield was compared between cows affected with lameness and healthy cows. RESULTS: 167 (31%) cows were affected with lameness during lactation. Lame cows had claw lesions (60%), papillomatous digital dermatitis (31%), or interdigital phlegmon (9%). Milk yield in lame cows with interdigital phlegmon (mean, 17,122 lb) was significantly less, compared with healthy cows (19,007 lb). CONCLUSIONS AND CLINICAL RELEVANCE: In this herd, interdigital phlegmon was associated with a 10% decrease in milk production. Lame cows with claw lesions or papillomatous digital dermatitis produced less milk than healthy cows, but the difference was not significant. 相似文献
75.
OBJECTIVE: To determine the effect of two doses of fentanyl, administered transdermally, on the minimum alveolar concentration (MAC) of isoflurane in cats. STUDY DESIGN: Prospective, randomized study. ANIMALS: Five healthy, spayed, female cats. METHODS: Each cat was studied thrice with at least 2 weeks between each study. In study 1, the baseline isoflurane MAC was determined in triplicate for each cat. In studies 2 and 3, isoflurane MAC was determined 24 hours after placement of either a 25 or 50 microg hour(-1) fentanyl patch. In each MAC study, cats were instrumented to allow collection of arterial blood and measurement of arterial blood pressure. Twenty-four hours prior to studies 2 and 3, a catheter was placed and secured in the jugular vein and either a 25 or 50 microg hour(-1) fentanyl patch was placed in random order on the left thorax. Blood samples for plasma fentanyl determination were collected prior to patch placement and at regular intervals up to 144 hours. After determination of MAC in studies 2 and 3, naloxone was administered as a bolus dose (0.1 mg kg(-1)) followed by an infusion (1 mg kg(-1) hour(-1)) and MAC redetermined. RESULTS: The baseline isoflurane MAC was 1.51 +/- 0.21% (mean +/- SD). Fentanyl (25 and 50 micro g hour(-1)) administered transdermally significantly reduced MAC to 1.25 +/- 0.26 and 1.22 +/- 0.16%, respectively. These MAC reductions were not significantly different from each other. Isoflurane MAC determined during administration of fentanyl 25 micro g hour(-1) and naloxone (1.44 +/- 0.16%) and fentanyl 50 micro g hour(-1) and naloxone (1.51 +/- 0.19%) was not significantly different from baseline MAC (1.51 +/- 0.21%). CONCLUSIONS AND CLINICAL RELEVANCE: Fentanyl patches are placed to provide long-lasting analgesia. In order to be effective postoperatively, fentanyl patches must be placed prior to surgery. Plasma fentanyl concentrations achieved intraoperatively decrease the need for potent inhalant anesthetics in cats. 相似文献
76.
Lina J?nsson Lars Roepstorff Agneta Egenvall Anna N?sholm G?ran Dalin Jan Philipsson 《Acta veterinaria Scandinavica》2013,55(1):34
Background
Soundness of an individual horse is important for animal welfare and owner economy. However, knowledge of health status in normal horse populations is limited due to lack of systematic health recordings. The aim of the investigation was to study the prevalence of veterinary clinical findings in 4-5-year-old Swedish warmblood riding horses, and their influence on overall health scores, where associations to future longevity has been indicated.Results
The prevalence of clinical findings in 8,281 horses examined during 1983–2005 was studied according to a standardised protocol and related to overall health scores in linear statistical models. Effects of sex, age, examination event and changes over time were included. In total, 49% of the horses had clinical findings of medical health (MED), 42% in hooves (HOOF) and 74% of palpatory orthopaedic health (PALP). However, only 6%, 3% and 24% had moderate or severe findings, of MED, HOOF and PALP, respectively. Flexion test reactions were reported in 21% of the horses (5% moderate/severe), heavily influencing the overall score (H2). One fifth of these horses also had findings of unprovoked lameness while 83% had PALP findings (44% with moderate/severe findings). Acute clinical signs, i.e. heat or soreness, had a large influence on the H2 score but were rare, whereas more common clinical findings had smaller effects on overall health. Large variations in recorded health results were observed among events. A decrease in findings has occurred since 1983, in particular for PALP findings.Conclusions
Results of occurrence and relevance of evaluated clinical findings could be used for advice on preventive actions to keep horses sound, and possibly for benchmarking, and genetic evaluation of health traits. The distinct effect of event on recorded clinical findings emphasises that further harmonisation of veterinary examinations are desirable. 相似文献77.
Jan J. Olli Åshild Krogdahl Ted S. G. A. M. van den Ingh Lars E. Brattås 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(1):50-60
Abstract Four processed soybean products were evaluated as protein sources for Atlantic salmon: solvent-extracted soybean meal (SBM44), dehulled and solvent-extracted soybean meal (SBM50), dehulled full-fat soybean meal (FFSBM) and soybean concentrate (SBC). The soybean products replaced high-quality fish meal at levels corresponding to 0, 14, 28, 42 and 56% soybean protein of total protein. Dietary inclusion of SBC, at the expense of fish meal, did not affect weight gain, carcass lipids, fecal excretion of nutrients or fecal dry matter content significantly. The nutritive value of the SBC protein appeared comparable to that of the fish meal. The three other soybean products impaired performance increasingly with increasing levels of inclusion, indicating lower nutritive value than for the fish meal. The favourable results seen with SBC indicated a great potential of soybean to become an important protein source for Atlantic salmon through improved processing. 相似文献
78.
The serine proteases, tissue‐ and urokinase‐type plasminogen activators (PLAT and PLAU) and their inhibitors SERPINE1/2 are regulators of plasminogen to plasmin conversion. They are widely expressed in ovarian tissues, including granulosa and cumulus cells, and their expression is regulated by gonadotropins. The aim of this work was to assess the effect of serine protease inhibitors (aprotinin and AEBSF) and SERPINE1/2 on FSH‐induced cumulus cell expansion, the production of prostaglandin E2 (PGE2) and retention of hyaluronic acid (HA) in expanding cumulus. The serine protease activity proved to be essential for the production of PGE2 and also for the retention of HA; the inhibition of plasminogen activators by SERPINE1/2 had the same effect. Collectively, these data indicate that plasmin is required for proper function of expanding cumulus cells in vitro and presumably also in vivo in the pre‐ovulatory follicles. 相似文献
79.
Elpetra P. M. Timmermans‐Sprang Helena M. Mestemaker Renske R. Steenlage Jan A. Mol 《Veterinary and comparative oncology》2019,17(3):413-426
Human epidermal growth factor 2 (HER2) overexpression leads to aggressive mammary tumour growth. Although the prognosis of HER2+ tumours in humans is greatly improved using biologicals, therapy resistance, which may be caused by increased phosphatidyl‐3‐kinase (PI3K), rous sarcoma proto‐oncogene (cSRC) or wingless‐type MMTV integration site family (Wnt) activity, is a major concern. A recent analysis of 12 canine mammary cell lines showed an association between HER2/3 overexpression and phosphatase and tensin homologue (PTEN) deletion with elevated Wnt‐signalling. Wnt‐activity appeared to be insensitive to phosphatidyl‐3‐kinase (PI3K) inhibitors but sensitive to Src‐I1. We hypothesized that Wnt activation, was caused by HER2/3‐activated cSRC activation. The role of HER2/3 on Wnt signalling was investigated by silencing HER2/3 expression using specific small interfering RNA (siRNAs). Next, the effect of an epidermal growth factor receptor (EGFR)/HER2 tyrosine kinase inhibitor on Wnt activity and migration was investigated and compared to other tyrosine kinase inhibitors (TKIs) of related signalling pathways. Finally, two TKIs, a cSRC and a PI3K inhibitor, were investigated in a zebrafish xenograft model. Silencing of HER1‐3 did not inhibit the intrinsic high Wnt activity, whereas the HER kinase inhibitor afatinib showed enhanced Wnt activity. The strongest inhibition of Wnt activity and cell viability and migration was shown by cSRC inhibitors, which also showed strong inhibition of cell viability and metastasis in a zebrafish xenograft model. HER2/3 overexpression or HER2/3‐induced cSRC activation is not the cause of enhanced Wnt activity. However, inhibition of cSRC resulted in a strong inhibition of Wnt activity and cell migration and metastasis. Further studies are needed to unravel the mechanism of cSRC activation and cSRC inhibition to restore sensitivity to HER‐inhibitors in HER2/3‐positive breast cancer. 相似文献
80.
Monika Ruszkowska Anna Nynca Lukasz Paukszto Agnieszka Sadowska Sylwia Swigonska Karina Orlowska Tomasz Molcan Jan P.Jastrzebski Renata E.Ciereszko 《畜牧与生物技术杂志(英文版)》2019,(1)
Background: Long non-coding RNAs(lncRNAs) may regulate gene expression in numerous biological processes including cellular response to xenobiotics.The exposure of living organisms to 2,3,7,8-tetrachlorodibenzo-p-dioxin(TCDD),a persistent environmental contaminant,results in reproductive defects in many species including pigs.The aims of the study were to identify and characterize lncRNAs in porcine granulosa cells as well as to examine the effects of TCDD on the lncRNA expression profile in the cells.Results: One thousand six hundred sixty-six lncRNAs were identified and characterized in porcine granulosa cells.The identified lncRNAs were found to be shorter than mRNAs.In addition,the number of exons was lower in lncRNAs than in m RNAs and their exons were longer.TCDD affected the expression of 22 lncRNAs(differentially expressed lncRNAs [DELs]; log2 fold change ≥ 1,P-adjusted 0.05) in the examined cells.Potential functions of DELs were indirectly predicted via searching their target cis-and trans-regulated protein-coding genes.The coexpression analysis revealed that DELs may influence the expression of numerous genes,including those involved in cellular response to xenobiotics,dioxin metabolism,endoplasmic reticulum stress and cell proliferation.Aryl hydrocarbon receptor(AhR) and cytochrome P450 1 A1(CYP1 A1) were found among the trans-regulated genes.Conclusions: These findings indicate that the identified lncRNAs may constitute a part of the regulatory mechanism of TCDD action in granulosa cells.To our knowledge,this is the first study describing lncRNAs in porcine granulosa cells as well as TCDD effects on the lncRNA expression profile.These results may trigger new research directions leading to better understanding of molecular processes induced by xenobiotics in the ovary. 相似文献