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91.
Bentonite was compared with activated charcoal as therapy for lantana poisoning in calves dosed 5 d previously with leaf material of the common pink-edged red taxon of Lantana camara. Both therapies were given by stomach tube as a single dose at 5 g/kg. Five of 6 calves in each of the groups given bentonite and activated charcoal recovered while 5 of 6 calves in the control group died. Calves given bentonite took 3 d longer on average to recover fully than those given activated charcoal but the effects of the 2 therapies on plasma total bilirubin concentrations were statistically indistinguishable. Bentonite was judged to have promise as a cheap alternative to activated charcoal for therapy of lantana poisoning of cattle.  相似文献   
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The aim of this study was to assess the ultrasonographic characteristics of ovulatory follicles in cyclic Western White Face ewes (December) that had received intravaginal sponges containing medroxyprogesterone acetate (MAP; 60 mg) for 12 days, with or without an injection of 500 IU of equine chorionic gonadotropin (eCG) at sponge removal. We hypothesized that quantitative echotextural attributes of the follicles in ewes treated only with MAP would differ from those in MAP/eCG-treated ewes, reflecting the increased antral follicular growth and secretory function under eCG influence. Digital images of ovulatory follicles obtained at 0 and 24 h after MAP sponge removal and at 24 h before ovulation in the eCG-treated (five ewes, 13 follicles) and control (six ewes, 9 follicles) animals, were subjected to computerized analyses. The mean diameter of ovulatory follicles increased (p < 0.001) 24 h after eCG treatment. The mean pixel intensity and heterogeneity of the follicular antrum (p < 0.001), as well as mean pixel intensity of the follicular wall and perifollicular ovarian stroma (p < 0.05), were greater in eCG-treated animals compared with control ewes 24 h after sponge removal and at 24 h before ovulation. Mean serum concentrations of oestradiol-17beta tended to increase (p = 0.06) 24 h after eCG treatment and the eCG-treated ewes exceeded (p < 0.05) control animals in progesterone concentrations from days 9-15 after ovulation. Our results support the hypothesis that large antral follicles in eCG-treated ewes exhibit distinctive echotextural characteristics. Follicular image attributes in eCG-treated ewes appear to be indicative of the changes in follicular morphology and secretory activity caused by the administration of the exogenous gonadotropin, which has both FSH- and LH-like activities.  相似文献   
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95.
Fibroblast growth factor (FGF10) acts at the cumulus oocyte complex, increasing the expression of cumulus cell expansion‐related genes and oocyte competency genes. We tested the hypothesis that addition of FGF10 to the maturation medium improves oocyte maturation, decreases the percentage of apoptotic oocytes and increases development to the blastocyst stage while increasing the relative abundance of developmentally important genes (COX2, CDX2 and PLAC8). In all experiments, oocytes were matured for 22 h in TCM‐199 supplemented with 0, 2.5, 10 or 50 ng/ml FGF10. In Experiment 1, after maturation, oocytes were stained with Hoechst to evaluate meiosis progression (metaphase I, intermediary phases and extrusion of the first polar body) and submitted to the TUNEL assay to evaluate apoptosis. In Experiment 2, oocytes were fertilized and cultured to the blastocyst stage. Blastocysts were frozen for analysis of COX2, CDX2 and PLAC8 relative abundance. In Experiment 1, 2.5 ng/ml FGF10 increased (p < 0.05) the percentage of oocytes with extrusion of the first polar body (35%) compared to 0, 10 and 50 ng/ml FGF10 (21, 14 and 12%, respectively) and FGF10 decreased the percentage of oocytes that were TUNEL positive in all doses studied. In Experiment 2, there was no difference in the percentage of oocytes becoming blastocysts between treatments and control. Real‐time RT‐PCR showed a tendency of 50 ng/ml FGF10 to increase the relative abundance of COX2 and PLAC8 and of 10 ng/ml FGF10 to increase CDX2. In conclusion, the addition of FGF10 to the oocyte maturation medium improves oocyte maturation in vitro, decreases the percentage of apoptotic oocytes and tends to increase the relative abundance of developmentally important genes.  相似文献   
96.
随着对鸡传染病防制技术水平的提高和相应的高科技产品的推广运用,加上政府和广大养鸡场(户)对典型新城疫(ND)和高致病性禽流感(HPAIH5亚型)防制工作的重视,成功地控制了这两种疾病的发生。但当前肉鸡业最易忽视、危害又最大的却是非典型新城疫(CND)和低致病力H9亚型禽流感(LPAI)。所谓“重视”是大家都接种了AI和ND疫苗,而忽视的是对AI只接种H5亚型而未接种H9亚型禽流感疫苗;  相似文献   
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98.
Conventional somatic cell nuclear transfer (SCNT) technique of in vitro production of cloned embryos involves use of costly and complicated micromanipulators. Handmade cloning (HMC) technique has been applied as efficient and cost‐effective alternative in many livestock species. The aim of the present study was to compare the efficiency of in vitro production and in vitro development of cloned sheep embryos by the two techniques. Cloned embryos were produced by conventional SCNT using micromanipulator apparatus and by HMC technique. Enucleation efficiency and efficiency of fusion with somatic cell (nucleus donor) were compared. Cleavage percentage was observed on day 2 of in vitro culture (IVC), and morula and blastocyst percentages were calculated on day 7 of IVC. Higher enucleation efficiency (96.98 ± 1.01 vs. 93.62 ± 1.03; p > .05) as well as fusion efficiency was obtained with HMC technique than with conventional SCNT (96.26 ± 1.34 vs. 92.63 ± 0.70, p < .05); 181 cloned sheep embryos were produced in vitro by conventional SCNT and 92 by HMC. Cleavage percentage observed on day 2 of in vitro culture was higher in HMC than SCNT (66.92 ± 3.72 vs. 55.97 ± 2.5, respectively, p < .05). Morula percentage obtained was higher in SCNT than HMC (44.12 ± 2.93 vs. 30.43 ± 6.79, respectively, p < .05), whereas blastocyst percentage obtained by HMC was higher (12.46 ± 4.96) than SCNT (5.31 ± 2.25; p > .05). It was inferred that HMC technique provides a cost‐effective and efficient method of in vitro production of cloned sheep embryos with a comparatively simpler technique with a possibility of automation. Efficiency of cloned embryo production could be improved further by propagating and standardizing this technique.  相似文献   
99.
This study was carried out to examine the changes in plasma concentrations of the Ca‐binding antimicrobial proteins S100A7 and S100A8 during pregnancy in dairy cows. Holstein Friesian cows (n = 19) were inseminated with Holstein Friesian semen. Blood was collected at days 30, 60, 90, 120, 150, 180, 210, 240 and 270 after insemination. Plasma was used for measuring the concentrations of S100A7 and S100A8. Both S100A7 and S100A8 concentrations showed similar patterns during gestation; they increased during the midgestation, between days 90 and 180, and then declined before calving. The findings indicated that plasma concentrations of S100A7 and S100A8 did not change significantly during pregnancy in cows. Further studies are required to determine the roles of S100A7 and S100A8 in physiological function during pregnancy in dairy cows.  相似文献   
100.
AIMS: To investigate the effect of targeted resynchronisation of cows treated for non-observed oestrus before the planned start of mating (PSM), that were not detected in oestrus or pregnant 23 days after treatment (phantom cows), on the proportion pregnant at 42 days after PSM and the end of mating.

METHODS: Farm staff from eight herds in two regions of the South Island of New Zealand identified 1,819 cows not showing oestrus by 10 days before PSM. These cows were treated with intravaginal progesterone for 7 days, and I/M gonadorelin 10 days and 1 day before PSM. Three days before PSM they were injected with cloprostenol and equine chorionic gonadotrophin, with fixed time artificial insemination (FTAI) at PSM. By 23 days after PSM, 1,218 cows had not returned to oestrus. Of these, 161 cows confirmed not pregnant by transrectal ultrasonography were randomly assigned to no treatment (control group; n=74) or were resynchronised 25 days after PSM using the same treatment programme as above, with FTAI 35 days after PSM (n=87). All cows that returned to oestrus were artificially inseminated until 42 days after PSM, when natural mating was used. All cows were examined using transrectal ultrasonography 80 to 90 days after PSM to confirm conception dates.

RESULTS: Of the 1,819 anoestrous cows treated before PSM, 526 (29 (95% CI=23.1–34.0)%) had not been observed in oestrus by 23 days after PSM and had not conceived, so were diagnosed as phantoms cows. For resynchronised cows, 42/87 (48 (95% CI=37.8–58.8)%) were pregnant by 42 days after PSM compared to 21/74 (28 (95% CI=18.1–38.7)%) control cows (p=0.009). At the end of mating 58/87 (67 (95% CI=56.6–76.7)%) cows in the resynchronised group were pregnant and 46/74 (62 (95% CI=50.9–73.2)%) in the control group (p=0.554). The hazard of conception from 21 to 42 days after PSM was 1.9 (95% CI=1.07–3.12) times greater for resynchronised than control cows (p=0.026).

CONCLUSION: In cows not observed in oestrus and treated before PSM, resynchronisation increased the proportion pregnant by 42 days after PSM.

CLINICAL RELEVANCE: The benefit of resynchronisation depends on the number of anoestrous cows before PSM and the number of phantom cows after PSM. However at the herd-level it is likely that providing advice to reduce the known risk factors for cows not being observed in oestrus before the PSM may well be more cost effective than identifying and treating a sub-population of phantom cows.  相似文献   

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