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31.
Objective To present the technique for intra-articular catheter placement and report the clinical outcomes of 38 cases of equine synovial trauma and/or infection treated with broad-spectrum antimicrobials administered via an intrasynovial catheter (ISC). Design Retrospective study. Procedure Medical records of 38 horses treated for synovial trauma and sepsis with frequent antimicrobial administration through an ISC from 1995 to 2008 were reviewed. Follow-up information was obtained via clinical re-evaluation or telephone contact with the owners. Results The majority of horses (84%) received amikacin and Timentin® four times daily. In addition, synovial lavage through the ISC was carried out in 27 horses (71%). Only radiological evidence of osteolysis had a significant negative impact on both lameness at the time of hospital discharge and the long-term outcome. In total, 92% of horses treated with frequent antimicrobial administration through an ISC had clinical resolution of infection. Catheter obstruction occurred in three cases, necessitating replacement or removal, and two synovial fistulae developed at sites of open drainage. The majority of horses treated had a favourable outcome, with 86% being at least pasture sound and 43% returned to riding. Conclusion Septic synovial structures treated with frequent antimicrobial administration through an ISC had a good prognosis for survival and 43% returned to riding, which is consistent with the results of other studies. The use of a simple ISC should be considered when broad-spectrum intrasynovial antimicrobial administration and lavage of a septic synovial structure are indicated.  相似文献   
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Polyunsaturated fatty acids are important membrane components that influence membrane integrity and fluidity. In the present study, the effect of oral supplementation for 60 days with essential fatty acids (omega 3, 6 and 9) and vitamin E on canine semen quality was evaluated. Sixteen dogs were selected for the experiment; eight were used as the control group and eight received the fatty acid supplemented diet for 60 days. Semen samples were taken every 15 days during the entire experimental period and were analyzed for volume (ml), motility (%), vigour (0–5), concentration (×106/ml), morphology of spermatozoa (%), plasma membrane integrity (%; using the hyposmotic swelling test) and thermoresistance (motility and vigour after 4 h at 38°C). We concluded that, daily supplementation with omega 3, omega 6 and omega 9 fatty acids, together with vitamin E, for a period of 60 days, significantly increased the semen volume of the treated group after 15 days of supplementation; the vigour and concentration of spermatozoa were superior after the first month of supplementation, while the percentage of morphologically abnormal spermatozoa decreased and the cells were protected against thermal stress.  相似文献   
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Experiments were designed to investigate the size distribution of queen steroidogenic luteal cells throughout pseudopregnancy. Corpora lutea were obtained from the queens following ovariohysterectomy on days 7, 15 or 25 of pseudopregnancy. Luteal cells were isolated from the ovary by collagenase digestion. Steriodogenic cells were identified by staining of cells for 3β-HSD activity. Cell diameters were measured using a microscope. Luteal cells having steroidogenic capacity covered a wide spectrum of sizes ranging from 3 to 35 μm in diameter. There was a significant increase in mean cell diameters (p < 0.01) as pseudopregnancy progressed. Mean diameter of 3β-HSD positive cells increased from 10.41 ± 0.7 μm, on day 7 of pseudopregnancy, to 19.72 ± 1.3 μm on day 25 of pseudopregnancy. The ratio of large (>20 μm in diameter) to small (3–20 μm in diameter) luteal cells was 0.08 : 1.0 on day 7 of pseudopregnancy, with the 7.5–10 μm cell size class predominant. By day 25 of pseudopregnancy, the ratio of large-to-small cells was increased to 0.87 : 1.0, and 20–25 μm cell sizes become predominant. In conclusion, this study has demonstrated that the cells of the corpus luteum undergo continuous differentiation during pseudopregnancy in queen. This study also demonstrates that luteal cells dissociated from pseudopregnant queen can be used as a model to study the physiology of corpus luteum in pregnant cats.  相似文献   
34.
The cryopreservation of spermatozoa constitutes a valuable tool for the captive breeding management of valuable and/or threatened species. Chinchilla lanigera is a species almost extinct in the wild, and the domestic counterpart has one of the most valuable pelts in the world. The objectives of this study were to: (i) compare the functional activity of post‐thawed chinchilla spermatozoa cryopreserved at ?196°C either with glycerol (G) or ethylene glycol (EG) as cryoprotectants (1 m final concentration) and (ii) investigate the effects of incubating the gametes for 4 h in the presence or in the absence of the cryoprotectants; evaluations were performed taking into account motility, viability, response to hypo‐osmotic shock and acrosome integrity of the cells. Parameters reflecting post‐thaw (0 h) sperm functional activity were significantly lower than those of freshly ejaculated gametes. When comparing the cryoprotectant efficiency of G vs EG, neither cryoprotectant agent offered appreciable advantages. After 4 h of incubation, in the presence or absence of the cryoprotectant agent, a rapid and significant decrease was found in all functional parameters and remained at ~ 20–30% motile, viable and viable acrosome intact cells. Viability was significantly lower when the cryoprotectant was removed from the media (possibly due to the centrifugation process). With respect to the maintenance of sperm membrane integrity, only ~ 10% of cells showed membrane resistance to hypo‐osmotic conditions after the 4 h incubation period. These results constitute new insights for cryopreservation protocols and the development of assisted reproductive techniques in this species.  相似文献   
35.
A full-length cDNA of a glutathione S-transferase (GST) was cloned from a cDNA library of the local Egyptian cattle tick Boophilus annulatus. The 672 bp cloned fragment was sequenced and showed an open reading frame encoding a protein of 223 amino acids. Comparison of the deduced amino acid sequence with GSTs from other species revealed that the sequence is closely related to the mammalian mu-class GST. The cloned gene was expressed in E. coli under T7 promotor of pET-30b vector, and purified under native conditions. The purified enzyme appeared as a single band on 12% SDS-PAGE and has a molecular weight of 30.8 kDa including the histidine tag of the vector. The purified enzyme was assayed upon the chromogenic substrate 1-chloro-2,4-dinitrobenzene (CDNB) and the recombinant enzyme showed high level of activity even in the presence of the beta-galactosidase region on its 5' end and showed maximum activity at pH 7.5. The Km values for CDNB and GSH were 0.57 and 0.79 mM, respectively. The over expressed rBaGST showed high activity toward CDNB (121 units/mg protein) and less toward DCNB (29.3 units/mg protein). rBaGST exhibited peroxidatic activity on cumene hydroperoxide sharing this property with GSTs belonging to the GST alpha class. I50 values for cibacron blue and bromosulfophthalein were 0.22 and 8.45 microM, respectively, sharing this property with the mammalian GSTmu class. Immunoblotting revealed the presence of the GST molecule in B. annulatus protein extracts; whole tick, larvae, gut, salivary gland and ovary. Homologues to the GSTmu were also detected in other tick species as Hyalomma dromedarii and Rhipicephalus sp. while in Ornithodoros moubata, GSTmu homologue could not be detected.  相似文献   
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The investigation was designed to study the gastro-intestinal helminth infection established in yearling calves with reference to fluctuations in the larval contamination of the herbage during the grazing season. In a 2 × 3 factor experiment, comprising six groups, each of six calves, a comparison was made between infection levels, growth rates etc. in calves grazing the same paddock over an entire season and calves moved before the July rise in herbage contamination to paddocks not grazed earlier in the same season. A comparison was also made between animals receiving no anthelminthic treatment, animals treated 3 weeks after the start of the grazing season and again when moved, and animals treated every 3 weeks during the season.Before July there were no weight gain differences between the various groups of calves. During the rest of the season, the calves which were moved gained 647–869 g, while those that remained on the same paddock, and were exposed to a high level of larval contamination gained only 81–361 g per day. The effect of anthelmintic treatment was less pronounced, though significant. The weight gains were correlated to a high degree with the larval contamination levels of the respective paddocks (r = ? 0.79) as well as with the serum pepsinogen (r = ? 0.75) and albumin levels (r = 0.75) of the calves and to a minor degree also with faecal egg counts (r = ? 0.45). The observed weight gain differences could not be accounted for by differences in grass quantity or quality.  相似文献   
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Mites associated with abandoned fig trees in Egypt were observed during a 2-year study. This study included species diversity and seasonal fluctuations as well as some biological aspects of common eriophyoid species. Three phytophagous species consisted of the fig bud mite Aceria ficus (Cotte), the fig leaf mite Rhyncaphytoptus ficifoliae Keifer and the two-spotted spider mite Tetranychus urticae Koch, representing a basic trophic level, were fed upon by three of predacious mites (Pronematus ubiquitus (McGregor), Amblyselus swirskii Athias-Henriot, Agistemus exsertus Gonzalez). Population abundance of the injurious mites were affected by the prevailing climatic conditions, action of predators and leaf age. A control measure of one summer pesticide (abamectin) application throughout the year seemed to be the most successful management of harmful mites. Life table parameters showed that the population of A. ficus multiplied 28.52 times in a generation time of 17.90 days, while R. ficifoliae population increased 16.50 times in a generation time of 14.61 days. Field and laboratory studies indicated that the viviparity is a typical character in the reproduction of R. ficifoliae.  相似文献   
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