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91.
Castration is one of the most common surgical procedures performed in equines and is associated with various complications, such as severe hemorrhage and evisceration. Using clinical, hormonal, and histopathological findings, this study aimed to evaluate a novel in situ castration technique and compare it with two other in situ techniques, namely, “section–ligation–release” (SLR) and “pinhole” (PH), to choose the most compatible and safe technique for sterilizing donkeys. Fifteen adult male donkeys were divided into three groups (five animals each). The vascular and the nonvascular parts of the spermatic cord were double ligated separately after opening the skin and the tunica vaginalis at the scrotal neck in the first group (incision–ligation [IL] technique, IL group). In the second group, donkeys were subjected to in situ castration using SLR technique, where both parts of the spermatic cord were triple clamped, ligated, and transected (SLR group). In the third group, percutaneous ligation of the spermatic vessels was performed without opening the skin (PH technique, PH group). The PH technique was less effective and failed to induce necrosis in the testes in situ. Also, Testosterone hormone levels remained elevated 60 days after this procedure. Although the IL and SLR techniques result in convincing reductions in resting and human chorionic gonadotropin–stimulated testosterone levels in treated donkeys, IL and SLR techniques were conducted under narcosis and strict asepsis. We concluded that the PH technique should not be recommended for sterilizing donkeys. Meanwhile, the IL and SLR techniques can be considered as an alternative to other conventional methods used for sterilizing donkeys.  相似文献   
92.
Three ellagitannins and one disulfated flavonol were isolated from the aerial parts of Reaumuria vermiculata L. Besides that, 16 known compounds were characterized as well. The structures of all compounds were elucidated on the basis of spectroscopic data including 1D and 2D NMR and ESI HR-FTMS. The in vivo antioxidant activity using the oxygen radical absorbance capacity (ORAC) method, of the extract, its column fractions and two of the isolated ellagitannins was accomplished. In addition, a possible cytotoxicity of the extract and two of the new ellagitannins on HaCaT human keratinocytes and the activity of both compounds against the prostate cancer cell line (PC-3) were also assessed, whereby a potent cytotoxicity with IC(50) less than 1μg/ml was determined for both compounds. Besides, the extract exhibited a potential cytotoxic effect against four different solid tumor cell lines, namely liver (Huh-7), colorectal (HCT-116), breast (MCF-7) and prostate (PC-3). The IC(50)s were found to be substantially low (ranged from 1.3±0.15 to 2.4±0.22μg/ml) with relatively low resistance possibility reaching to 0% in the case of Huh-7 cell.  相似文献   
93.
Four crude wild plants extract of Artemisia herba-alba Asso, Artemisia monosperma Del., Euphorbia aegyptiaca Boiss. and Francoeuria crispa (Forsk.) extracted with four successive solvents; hexane, diethyl ether, ethyl acetate and ethanol were evaluated against the third instar larvae of Chrysomyia albiceps using dipping and thin film techniques. In dipping technique, larvae were immersed in the concentrations of plant extracts for 30 seconds. However, in thin film technique, larvae were exposed to thin layer from each plant extract in the Petri-dishes. Results showed that all extracts had toxic effects on larvae in both two treatments. Hexane and diethyl ether extracts of A. herba-alba and ethyl acetate extract of A. monosperma recorded the highest effect in both two treatments. Ethanol extracts of E. aegyptiaca and A. monosperma were the highest in dipping and thin film treatments, respectively. In dipping treatment, most plant extracts revealed extending effect on pupae especially while in thin film treatment most larvae which succeeded to develop to pupae produced normal flies. Deformed pupae were only recorded with the high concentration of diethyl extracts of A. herba-alba. Hexane, diethyl ether and ethyl acetate extracts of F. crespa only produced low percentages of deformed flies. Histological examination conducted on larvae confirmed that extracts in thin film treatment penetrated to the gut and destroyed its epithelial cells and wall. It concluded that the crude extracts of the four tested plants can be used in controlling of C. albiceps larvae while hexane extracts of E. aegyptiaca, A. herba-alba and A. monosperma are considered the most promising plant preparations against the larvae by using thin film technique.  相似文献   
94.
Background: The California mastitis test (CMT) and somatic cell count (SCC) are commonly used for diagnosis of subclinical mastitis in cattle. Acute phase proteins (APPs), as alternative biomarkers of mastitis, may increase in concentration in the absence of macroscopic changes in the milk, or may precede the onset of clinical signs. Objective: The aim of this study was to compare the accuracy of APPs measured in milk and in serum with bacterial culture for the diagnosis of bovine subclinical mastitis. Methods: One hundred and seventy‐five Holstein cows were randomly selected from 7 dairy farms. Quarter milk and serum samples were taken from all cows. Milk samples were analyzed using a CMT and SCC, and for haptoglobin (MHp) and amyloid A (MAA) concentrations, and were also submitted for bacterial culture. Serum samples obtained concurrently were analyzed for haptoglobin (SHp) and amyloid A (SAA). Two‐sample Wilcoxon (Mann–Whitney) test was used to compare SCC, MAA, MHp, SAA, and SHp concentrations between culture‐positive and culture‐negative animals. Receiver‐operating characteristic analysis was used to assess the performance of each test using bacterial culture as the reference method. Results: MAA concentration was the most accurate of the 5 tests, with a sensitivity of 90.6% and specificity of 98.3% at concentrations >16.4 mg/L. MAA and MHp had significantly larger areas under the curve than the respective serum proteins, SAA and SHp. Conclusions: The results suggest that measuring haptoglobin and amyloid A in milk is more accurate than serum analysis for the diagnosis of subclinical mastitis in Holstein cows.  相似文献   
95.
The goal of this study was to assess if oxidative stress, as measured by alterations in the concentrations of antioxidant enzymes in the liver and erythrocytes of cattle, could be induced following dl-ethionine administration. Whole blood, serum and liver biopsy samples were collected 0, 4, 7 and 10 days after intra-peritoneal ethionine administration to five cows. The activities of the antioxidant enzymes copper zinc superoxide dismutase (Cu, Zn SOD) and catalase were assessed in the liver biopsies which were also examined histopathologically.Significant increases in hepatic Cu, Zn SOD concentrations (P < 0.01) were noted on days 7 and 10 post-treatment. Hepatic catalase activity decreased significantly (P < 0.01) on days 4, 7 and 10 post-treatment and erythrocyte Cu, Zn SOD activity was significantly increased on day 10. Serum biochemical analysis revealed a significant increase (P < 0.01) in non-esterified fatty acid concentrations on day 4 and significant decreases in total cholesterol and phospholipid levels on days 4 (P < 0.05), 7 (P < 0.01) and 10 (P < 0.01). In this model system, dl-ethionine administration was effective in inducing oxidative stress particularly reflected in the liver.  相似文献   
96.
This study aimed to develop a system of in vitro assays based on zona pellucida binding and in vitro fertilization for predicting male fertility in buffalo bulls. Frozen–thawed semen from nine bulls was tested for motility, viability index, acrosomal integrity, zona pellucida binding and in vitro fertilizing ability. Differences in post-thaw sperm motility between bulls were not significant. Differences in viability indices and percentage of spermatozoa with detached acrosome between bulls was highly significant (P < 0.001). Sperm attached per ovum, fertilization rates and polyspermy percentages varied significantly (P < 0.01) among buffalo bulls. A significant (P < 0.01) positive correlation coefficient of 0.69 was evident between normal acrosome and sperm attached per ovum, while between normal acrosome and fertilization efficiency it was 0.72. Sperm from different buffalo bulls differs in their ability to bind and fertilize oocytes. This study provides a basis to predict and maximize the in vitro fertilization performance of individual bulls.  相似文献   
97.
The effect of sucrose concentration on callus induction followed by differentiation of embryogenic callus derived from petal explants of four carnation cultivars (Nelson, Sagres, Spirit and Impulse) was investigated. Embryogenic calli were produced on Murashige and Skoog [Murashige, T., Skoog, F.A., 1962. Revised medium for rapid growth and bioassays with tobacco tissue cultures. Physiol. Plant 154, 73–479] basal medium (MS) culture medium containing six concentrations of sucrose (3, 6, 9, 12, 15 and 18%, w/v) all supplemented with 9 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 0.8 μM 6-benzyladenine (BA). Maximum frequency of embryogenic callus was obtained from the media containing 9 and 12% sucrose. Somatic embryos were induced on a hormone-free MS media containing the seven concentrations of sucrose. Development of somatic embryos was enhanced by increasing sucrose concentration from 1.5 to 12%, while it was reduced in higher concentrations of 15 and 18%. However, normal embryos were not developed in the media containing 1.5 and 3% sucrose. Ninety-five percent of somatic embryos were regenerated to form the entire plantlets when they transferred onto the half-strength hormone-free MS culture medium containing 3% sucrose. Plantlets were also continued to grow normally under greenhouse condition.  相似文献   
98.
From March 1996 to February 1997, slaughtered-sheeps' heads were examined for the metacestode of Taenia multiceps. Out of 451 sheep heads, only 12 (3%) were infested. All cysts but one were in the age group 0.5-2.5 years old, with prevalence of 10% (11 of 108). Eleven of 12 infested heads were found during the spring and autumn seasons. Out of 95 flocks involved in questionnaire survey unrelated to the abattoir survey, all the farmers reported the existence of the clinical signs known for coenurosis and described it in locally known names and diseases. Twenty-five of them had recent cases that were diagnosed by the veterinarian as coenurosis cases. Each flock reported one or two cases at the time of survey. A variety of clinical signs were reported from these cases (n = 42). These included circling (86%), head pressing (52%), blindness (29%) and paresis (40%). Coenurosis is a sheep-health problem and an important cause of sheep culling in Jordan.  相似文献   
99.
Summary Five diagnostic tests for infection withTrypanosoma evansi have been compared in groups of camels experimentally infected or exposed to natural infection in the Sudan. The correlation of positive results obtained by assays of IgM levels, the mercuric chloride test and the formol gel test with the presence of active infection was unsatisfactory, but there was a good correlation between results obtained using IFAT and ELISA and proven infection. Sera from a high proportion of apparently uninfected camels from endemic areas gave positive reactions with all 5 tests, possibly indicating inadequate parasitological diagnosis or persistence of antibody after unsatisfactory chemotherapy. It was concluded that serological tests using trypanosomal antigens to detect antibodies were more sensitive for diagnosis than indirect tests based on raised euglobulin levels. Serodiagnostic tests may therefore have a place in future programmes for surveillance and control ofT. evansi infections in camels.
Serodiagnostico De La Infeccion PorTrypanosoma Evansi En Camellos En Sudan
Resumen Se compararon cinco pruebas diagnósticas para infecciones porTrypanosoma evansi en grupos de camellos infectados experimentalmente o expuestos a la infección natural. La correlación de los resultados positivos utilizando pruebas de difusión radial aisladas, le niveles de IgM, la prueba de cloruro de mercúrio, y la prueba de agar formol con la presencia de infección activa, fue insatisfactória. Hubo buena correlación entre los resultados obtenidos con IFAT y ELISA con infección comprobada. El suero de una proporción alta de camellos aparentemente sanos, provenientes de áreas endémicas, presentaron reacciones positivas con las cinco pruebas, indicando posiblemente un diagnóstico parasitológico inadecuado, o la persistencia de anticuerpos despues de una quimioterápia inadecuada. Se concluyó, que las pruebas serológicas usando antígenos preparados de tripanosomas para detectar anticuerpos, fueron más sensitovos que las pruebas indirectas basadas en el aumento de euglobulinas. Las pruebas serodiagnósticas posiblemente tendran un lugar en programas futuros de reconocimiento y control deT. evansi en camellos.

Serodiagnostic De La Trypanosomose AT. Evansi Chez Le Chameau Du Soudan
Résumé Cinq méthodes de diagnostic de la trypanosomose àT. evansi chez le chameau ont été comparées en utilisant des chameaux expérimentalement et naturellement infectés, au Soudan. La corrélation des résultats positifs obtenus par utilisation de la diffusion radiale des Igm, par le test au chlorure mercurique et par le test de la formol gélification à l'occasion des infections en évolution, n'a pas été satisfaisante alors qu'il y a eu bonne corrélation entre les résultats obtenus par IFAT et ELISA et des infections véritables.Les sérums d'une importante proportion de chameaux apparemment non infectés, en provenance de régions à maladie endémique, ont donné des réactions positives aux cinq tests, ce qui peut indiquer soit une insuffisance dans le diagnostic parasitologique soit la persistance d'anticorps résultant d'une chimiothérapie insuffisánte.Les auteurs concluent que les tests sérologiques utilisant des trypanosomes comme antigènes pour mettre les anticorps en évidence sont plus sensibles, en matière de diagnostic, que les tests indirects basés sur la détection des niveaux des IgM. C'est pourquoi les tests faisant appel aux méthodes de sérodiagnostic doivent avoir leur place dans les programmes à venir concernant tant la surveillance que la lutte contre les infections du chameau àT. evansi.
  相似文献   
100.
The goal of the present study was to measure the total glutathione level and glutathione reductase activity in bovine erythrocytes and liver biopsy. Five cows were injected intraperitoneally with DL-ethionine (12.5 mg/kg B.W.), and two control cows were injected with normal saline (0.9% NaCl). Ultrasonography guided liver biopsy, and blood samples were collected at 0, 4, 7 and 10 days after injection. The hepatic total glutathione level was significantly increased on Days 7 (p<0.05) and 10 (p<0.01), and hepatic glutathione reductase activity was significantly increased on Days 4 (p<0.05), 7 (p<0.01) and 10 (p<0.01). There were insignificant changes in the erythrocytic total glutathione level. The present study demonstrated that liver biopsy is a valuable tool for detecting oxidative stress and for diagnosing hepatic dysfunction in cattle from the viewpoint of the status of glutathione and glutathione reductase.  相似文献   
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