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21.
The objectives of the present study were to investigate the relationship between the morphological status of cumulus cells surrounding canine oocytes after maturation culture and the meiotic stage of the oocytes. In addition, the effect of the removal of cumulus cells from canine cumulus-oocyte complexes (COCs) during maturation culture on their meiotic competence was examined. Canine COCs were collected from bitches at the anoestrous and dioestrous stages and only COCs with >110 microm in vitelline diameter were cultured in medium 199 with 10% canine serum for 72 h. In the first experiment, the relation between the morphological status of cumulus cells surrounding oocytes cultured for 72 h and their meiotic stages was examined. At the end of maturation culture, the proportions of intact, partially nude and completely nude oocytes were 65.2%, 22.9% and 11.9%, respectively. The proportion of maturation to metaphase II of completely nude oocytes was highest among the oocytes with different morphological status of cumulus cells. In the second experiment, the cumulus cells were partially or completely removed from COCs at 48 h after the start of maturation culture and the oocytes were cultured for a further 24 h. The proportion of oocytes reaching metaphase II in the completely denuded oocytes was significantly higher than that in the control oocytes without the removal treatment of cumulus cells. The results indicate that morphological status of cumulus cells surrounding oocytes may be related to the nuclear maturation of canine oocytes, and the removal of cumulus cells from COCs during maturation culture can promote the completion of oocyte meiotic maturation. 相似文献
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SUMMARY Chronic fluoride toxicosis caused lameness, dental lesions and illthrift in an extensive beef cattle herd in northern Australia. Up to 15% of the herd was lame and the disease forced the culling of large numbers of cows. The source of fluoride was fertiliser-grade monoammonium and diammonlum phosphate fed as part of a mineral supplement. Large quantities of mineral supplement were provided to the cattle because lameness was attributed to phosphorus deficiency, which is endemic in the area. Most lameness developed in the late dry season in the post-lactation phase. Severe lameness was caused by fractured pedal bones. 相似文献
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Comparison of the Johne''s absorbed EIA and the complement-fixation test for the diagnosis of Johne''s disease in cattle 总被引:2,自引:0,他引:2
SE RIDGE IR MORGAN DC SOCKETT† MT COLLINS† RJ CONDRON NW SKILBECK† JJ WEBBER§ 《Australian veterinary journal》1991,68(8):253-257
A commercially available absorbed ELISA for the diagnosis of Johne's disease (JD) (paratuberculosis) in cattle, the Johne's Absorbed EIA, was compared with the conventional complement-fixation test (CFT) used in Australia. Stored plasma from 3 Victorian dairy herds with a history of JD, sera from specimens submitted from animals showing clinical signs of JD and sera from the US National Repository for Paratuberculosis Specimens were used to determine the sensitivity of each test. The EIA detected 48.8% of 43 Australian animals with subclinical JD, while the CFT detected only 12 (21.4%) of 56 subclinically affected cattle. Of 150 subclinically infected US cattle, the EIA detected 47.3% and the CFT detected 52.0%. The EIA detected 59.7% of animals which at the time of sampling were shedding Mycobacterium paratuberculosis in their faeces, but showed no clinical signs of JD, while the CFT detected 57.3%. The EIA correctly identified 88.2% of 136 histologically confirmed clinical cases, and the CFT detected 83.4%. The specificity of each test was determined by testing sera collected at slaughter from animals residing in a known JD-free area of Australia, and from samples from the US National Repository of Paratuberculosis Specimens collected from certified-free herds in Wisconsin. The EIA was found to have a specificity of 99.8% when 998 Australian animals were used as the test population, and 99.0% when 196 US animals were used. The specificity of the CFT using Australian samples was 96.9% and 95.2% using American samples. 相似文献
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RS Robinson AJ Hammond DC Wathes MG Hunter GE Mann 《Reproduction in domestic animals》2008,43(S2):104-112
Conception rates of dairy cows are currently declining at an estimated 1% every year. Approximately, 35% of embryos fail to prevent luteolysis during the first three weeks of gestation. Interactions between the corpus luteum, endometrium and embryo are critical to the successful establishment of pregnancy and inadequacies will result in the mortality of the embryo. For example, as little as a one day delay in the post-ovulatory rise of progesterone has serious consequences for embryo development and survival. Recently, we found that LH support, degree of vascularization and luteal cell steroidogenic capacity were not the major factors responsible for this luteal inadequacy, but are nevertheless essential for luteal development and function. Progesterone acting on its receptor in the endometrium stimulates the production of endometrial secretions on which the free-living embryo is dependent. However, their exact composition and effects of inadequate progesterone remains to be determined. The embryo is recognized through its secretion of interferon tau (IFNT), which suppresses luteolytic pulses of prostaglandin F2α . In the cow, it is most likely that IFNT inhibits oxytocin receptor up-regulation directly and does not require the prior inhibition of oestrogen receptor α (ESR1). Unravelling the precise luteal-endometrium and embryo interactions is essential for us to understand pregnancy establishment and development of strategies to reverse the declining fertility of dairy cows. 相似文献
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J. Brad Case DVM MS DACVS Ross Palmer DVM MS Diplomate ACVS Alex Valdes‐Martinez DVM Diplomate ACVR Erick L. Egger DVM Diplomate ACVS Kevin K. Haussler DVM DC PhD Diplomate ACVSMR 《Veterinary surgery : VS》2013,42(4):355-360
Objective
To report clinical findings and outcome in a dog with gastrocnemius tendon strain treated with autologous mesenchymal stem cells and a custom orthosis.Study Design
Clinical report.Animal
A 4‐year‐old spayed female Border Collie.Methods
Bone‐marrow derived, autologous mesenchymal stem cells were transplanted into the tendon core lesion. A custom, progressive, dynamic orthosis was fit to the tarsus. Serial orthopedic examinations and ultrasonography as well as long‐term force‐plate gait analysis were utilized for follow up.Results
Lameness subjectively resolved and peak vertical force increased from 43% to 92% of the contralateral pelvic limb. Serial ultrasonographic examinations revealed improved but incomplete restoration of normal linear fiber pattern of the gastrocnemius tendon.Conclusions
Findings suggest that autologous mesenchymal stem cell transplantation with custom, progressive, dynamic orthosis may be a viable, minimally invasive technique for treatment of calcaneal tendon injuries in dogs. 相似文献27.
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Oocyte viability and cortical activation under different salt solutions in Prochilodus lineatus (Teleostei: Prochilodontidae) 下载免费PDF全文
DC Ribeiro JMA Chagas C Bashiyo‐Silva RS Costa R Veríssimo‐Silveira A Ninhaus‐Silveira 《Reproduction in domestic animals》2017,52(6):932-938
This study aimed to evaluate the effect of five salt solutions in the maintenance of morphological features of cortical alveolus, hydration and fertilization capacity of Prochilodus lineatus oocytes. For this purpose, five saline solutions were tested: Ringer's solution, Ringer's lactate solution, Hank's balanced salt solution (HBSS), Hank's balanced salt solution without calcium (HBSS without calcium) and solution for salmonid eggs. Oocytes were maintained for 2 hr in saline solution with controlled temperature subsequently evaluated for hydration, cortical activation and fertilization ability. In the evaluation of the fertilization ability, two controls were used: C1—fertilized oocytes after extrusion—and C2—oocytes kept in ovarian fluid and fertilized after 2 hr. There was a significant reduction in the viability of oocytes C2 (28.8% ± 12.9%) compared to C1 (65.3% ± 26.7%), and no significant differences were found between treatments HBSS and HBSS without calcium and C2. Only HBSS and HBSS without calcium maintained the non‐activated state of the gametes, with a fertilization rate of 16.4% ± 6.7% and 5.6% ± 2.3%, respectively; however, they did not extend the viability of oocytes, such that they continued to undergo degradation during the storage period, similar to oocytes retained only in ovarian fluid. 相似文献
29.
AK Ghosh D Sarkar DC Nayak P Bhattacharyya 《Archives of Agronomy and Soil Science》2013,59(6):583-591
A sequential fractionation scheme, based on a soil phosphorous fractionation, was developed to assess the chemical nature, and thus the potential bioavailability and mobility of As, at the sites. Soil As was separated into five fractions with (i) anion exchange resin, (ii) NaHCO3, (iii) NaOH, (iv) HCl, (v) residual. Most sites contained relatively low concentrations of As in the two most labile fractions. The bulk of the contaminant As at the sites seemed to be associated with soil amorphous Fe and Al minerals and the dominant clay minerals which help in As sorption are montmorillonite and mica. Resin-extractable As in particular might provide a good index of potential As bioavailability and mobility. 相似文献
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