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Objective   To evaluate the effect of a non-occlusive dressing incorporated in a 3-layer bandage on second intention healing of wounds of the distal portion of the limb.
Study Design   Untreated wounds in 33 adult horses used in four studies using the same wound-healing model conducted over 5 years.
Methods   Standardised, full-thickness wounds were made in the skin overlying the dorsomedial aspect of the mid-metacarpus; 17 horses were bandaged with a non-occlusive dressing covered by gauze-coated cotton wool that was compressed with adhesive tape; 16 horses were left unbandaged. Wounds were photographed weekly for 9 weeks and the images were analysed electronically.
Results   There were significant effects associated with bandage (P < 0.0001), week (P < 0.001), and bandage by week interaction (P < 0.0001). There was no difference in wound area at the first time-point after wound creation (P = 0.38). After week 1, there was a difference between bandaged and unbandaged wounds in wound area at each measurement until the end of the study. Bandaged wounds showed greater and more prolonged retraction. Unbandaged wounds retracted for 2 weeks before beginning to contract, whereas bandaged wounds continued to retract for 3 weeks. In bandaged wounds excess granulation tissue required regular trimming, but not in unbandaged wounds. There was no difference between groups in the total days to healing or the overall rate of healing.
Conclusions   These results should be treated with caution until validated with contemporaneous, controlled studies. Covering a wound with a non-occlusive dressing in a 3-layer bandage led to greater wound retraction, modulated the rate of wound contraction and promoted excessive granulation tissue. If excessive granulation tissue is excised regularly, bandaging has no effect on total time to healing.  相似文献   
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This study was conducted to determine the in vitro effects of three different concentrations (125, 187.5 and 250 microM in diluted semen) of zearalenone (zen) and alpha-zearalenol (alpha-zen) on boar sperm. Semen parameters such as motility, viability and spontaneous acrosome reaction were evaluated. From the results it was shown that both zen and alpha-zen affected the sperm characteristics significantly (p < 0.05), except for alpha-zen at the low concentration which did not decrease the percentage of live reacted spermatozoa significantly. In conclusion, zen and alpha-zen are directly toxic when they affect boar semen in vitro and consequently decrease the fertilization ability of the sperm. The higher the concentration of mycotoxin tested, the greater the decline of sperm parameters noticed. The influence of mycotoxins was found to be time- and dose-dependent.  相似文献   
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This short communication reports the impact of endometrial biopsies, uterine flushings and follicular fluid aspiration procedures at day 6 post artificial insemination (AI) on pregnancy rates. In Experiment 1, cows were timed AI (TAI) and assigned to the following treatment groups: control (n = 37), uterine flushing (n = 35) and endometrial biopsy (n = 38). On day 30 post AI, pregnancy rates were 40.5%, 33% and 28.5%, respectively (p > 0.1). Pregnancy rate on day 60 was lower (p < 0.004) in flushed cows than in the controls. In Experiment 2, oestrus was detected and cows were assigned to flushing (n = 32) or biopsy (n = 33) treatments 6 days after AI, which resulted in pregnancy rates of 31% and 36%, respectively (p > 0.1). In Experiment 3, cows were, 6 days after TAI, randomly assigned to the following treatments: control (n = 84) or aspiration of the largest follicle (n = 73). Pregnancy rates on day 30 post AI were 63.5% for the control group and 53% for the aspirated group (p > 0.1). In conclusion, uterine flushing and endometrial biopsy negatively affect pregnancy rates, but neither procedure can be considered to be incompatible with pregnancy maintenance. Follicular aspiration during pregnancy does not interact with pregnancy success. The amount and quality of samples obtained are compatible with the use of cellular and molecular analysis of uterine variables from cows that failed or succeeded on maintaining pregnancy.  相似文献   
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Flow cytometry is considered the only reliable method for the separation of X and Y chromosome bearing spermatozoa in equines. The MoFlo SX DP sorter is highly efficient, allowing the production of foals of the desired sex. However, to achieve acceptable pregnancy rates the currently used protocol requires working with fresh semen obtained close to, or at, the sorting facility. An alternative protocol was tested during two consecutive breeding seasons. Fresh stallion semen was cooled for 20 h, during which staining with Hoechst 33342 took place. On the following day, this sample was flow sorted and compared with spermatozoa from the same ejaculate that had been sexed on the previous day. All sperm parameters evaluated remained unchanged when fresh sorted and refrigerated sorted semen were compared. Pre‐sorting storage at 5°C did not alter sperm velocities nor kinetics, viability or membrane permeability, production of reactive oxygen species, mitochondrial membrane potential or DNA fragmentation index of the sorted sample. The findings open for the possibility of using semen from stallions housed far from the sorting facilities. Processed and stained sperm could be shipped refrigerated on the previous day, sorted and inseminated on the next day.  相似文献   
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