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排序方式: 共有318条查询结果,搜索用时 15 毫秒
1.
In Vivo Embryo Recovery Rate by Laparoscopic Technique from Rabbit Does Selected for Growth Rate 总被引:1,自引:0,他引:1
Rabbit does from R line selected for growth rate present a low reproductive performance and this study aimed to evaluate both the recovery efficacy and viability of recovered embryos after vitrification and the reproductive performance of donor does subjected to in vivo recovery. Does were divided into three groups: 28 does without in vivo recovery (control), 25 does in which in vivo recovery was started in the nulliparous state (group 1) and 30 does with at least one litter before in vivo recovery (group 2). Does were superovulated with a single subcutaneous injection of 50 IU of equine chorionic gonadotropin (eCG) per female, and were then artificially inseminated 60 h later and immediately administered an intravenous dose of 75 IU of human chorionic gonadotropin (hCG) per female. Does from group 1 and 2 were recovered in vivo 76-80 h post-insemination by repeated laparoscopies at one to four times and permitted one or two parturitions between recoveries [in vivo (IV) recovery]. At the end of the experiment, about 16 does of all groups were recovered post-mortem (PM recovery). All normal embryos were vitrified, devitrified and then cultivated in vitro to evaluate the viability after thawing. A significant increase in the ovulation rate was found in does recovered PM than in those recovered IV in the nulliparous state. However, no significant differences were observed in the recovery rate, the donor rate, the number of normal embryos recovered with at least one normal embryo per doe and the viability after thawing between the PM and IV groups. A significant decrease in the fertility rate, total born, live born and weaned kids was found for does from group 1 in comparison with does from group 2. Results support the use of repeated laparoscopy to increase the number of recovered embryos per donor doe especially in such R line does, if they are permitted to produce at least one litter before the beginning of in vivo recovery. 相似文献
2.
F Marco-Jiménez S Puchades E Mocé MP Viudes-de-Cartro JS Vicente M Rodriguez 《Reproduction in domestic animals》2004,39(6):438-441
Egg yolk is a common additive to sperm cryopreservation diluents. Because of its animal origin, however, it also represents a potential risk of microbiological contamination in the diluent. This potential contamination can be avoided by using powdered egg yolk, instead of fresh egg yolk, as it is pasteurized. This study was conducted to determine ram sperm cryosurvival was affected by the type of egg yolk used (powdered egg yolk or fresh egg yolk) and by yolk concentration (10, 15 or 20%) in the diluent. Microbiological analyses were also performed to quantify the microbiological contamination in the diluents containing the two types of egg yolk. Sperm cryosurvival was determined by motility and morphology analyses after thawing. Motility parameters were assessed using a computer-assisted sperm analysis (CASA) system, and the percentage of sperm with a normal apical ridge was evaluated using a differential interference contrast microscope. No significant differences were observed between diluents in the percentage of sperm with normal apical ridge. However, higher percentages of total motile cells were observed for samples containing powdered egg yolk (69%) compared to samples containing fresh egg yolk (60%). However, sperm in diluents containing fresh egg yolk, exhibited higher values for average-path velocity, straight-line velocity and beat cross frequency and lower values for amplitude of lateral head displacement (p <0.05), compared to cells in diluents containing powdered egg yolk. Microbiological contamination was similar (<200 CFU/ml) in both diluents, and no bacterial growth was observed in either, when antibiotics were added. Therefore, powdered egg yolk can be effective used in diluents for the freezing of ram semen. However, the in vivo fertility of sperm frozen in diluents containing powdered egg yolk should be tested, as some motility parameters were different for sperm treated with powdered egg yolk compared to fresh egg yolk. 相似文献
3.
JS Munday H Bentall D Aberdein M Navarro FA Uzal S Brown 《New Zealand veterinary journal》2020,68(4):242-246
ABSTRACTCase history and clinical findings: A flock of 20 sheep was kept within three paddocks on a single property. None of the animals in the flock had been vaccinated against any disease for at least three years. Abdominal bloating and haemorrhagic diarrhoea were observed in Lamb 1 at 24 hours-of-age. The lamb subsequently died within an hour of the onset of clinical signs. Lamb 2 was 3-days-old when observed to be recumbent with opisthotonus. The lamb was treated with dextrose, vitamins B1 and B12, and penicillin G, but died 4 hours later.Pathological findings: Examination of Lamb 1 revealed markedly increased gas within the peritoneum and within dilated loops of intestine. The intestines were dark red and contained large quantities of haemorrhagic fluid. Histology of the intestines revealed peracute mucosal necrosis with minimal accompanying inflammation. The intestinal lumen contained cell debris, haemorrhage, and myriad large Gram-positive bacilli. The intestines of Lamb 2 did not appear bloated or reddened. However, multiple fibrin clots were visible within the pericardial sac. Histopathological examination revealed small foci of necrosis within the mucosa of the distal intestine. The necrotic foci were often associated with large numbers of large Gram-positive bacilli.Immunohistochemsitry and molecular biology: Intestinal samples from Lamb 1 were processed for Clostridium perfringens immunohistochemistry, which revealed large numbers of intralesional, positively immunostained rods. Fragments corresponding to the expected sizes for genes encoding alpha, beta, and epsilon C. perfringens typing toxins were amplified by PCR from DNA extracted from formalin-fixed sections of intestine.Diagnosis: Lamb dysentery due to C. perfringens type B.Clinical relevance: C. perfringens bacteria have a worldwide distribution, but disease due to C. perfringens type B has only been diagnosed in a small number of countries and has never been reported in New Zealand or Australia. C. perfringens type B produce both beta toxin and epsilon toxins, therefore both haemorrhagic enteritis and systemic vascular damage can develop. As many animals are exposed to C. perfringens without developing disease, there must be additional unknown factors that resulted in disease in these particular sheep. Vaccines that specifically protect against C. perfringens type B are available and may be recommended for use in smaller non-commercial flocks, as in the present case. 相似文献
4.
Zoledronate is a bisphosphonate frequently used for the treatment of hypercalcaemia of malignancy and tumour-associated bone pain in dogs, however, there is a paucity of information regarding its use in veterinary medicine. The aim of this retrospective study was to report the tolerability of zoledronate in the palliative treatment of cancer-bearing dogs and secondarily to to assess the efficacy of zoledronate for the treatment of hypercalcaemia of malignancy. Thirty-seven dogs (22 with tumour-associated bone pain and 15 with hypercalcaemia of malignancy) that received 114 zoledronate infusions were included. Tolerability was assessed by the absence of post-zoledronate hypocalcaemia or other adverse events as defined by Veterinary Cooperative Oncology Group-Common Terminology Criteria for Adverse Events criteria. Efficacy was assessed by comparison of available ionized calcium levels before and after zoledronate administration in hypercalcaemic dogs. In 79% of zoledronate infusions, no adverse events were reported. The majority of adverse events which occurred in the other 21% of infusions could be attributed to concurrent chemotherapy or the underlying neoplastic disease. There was a small but significant increase in creatinine following treatment with zoledronate, however, none of the dogs developed clinically significant renal disease. In eight hypercalcaemic dogs with available ionized calcium following zoledronate administration, ionized calcium decreased rapidly within 7 days following treatment with zoledronate. Zoledronate is well-tolerated with few recorded adverse events, however, monitoring of serum creatinine is advised. Zoledronate seems to be effective in the treatment of hypercalcaemia of malignancy. 相似文献
5.
Natural vegetation on erodible land surfaces, such as the loose sandy soils found in the southwestern United States and in Soviet Central Asia, absorbs part of the wind momentum flux (stress) and thus protects the erodible soil to a degree that depends on the geometry of plant distribution and profile. The sheltering effect of natural plants may be expressed as the ratio, R, of threshold friction velocity for the bare soil (determined in the laboratory or in specially prepared areas of bare soil in the field) to that for the naturally vegetated surface. We used new automated instrumentation to detect erosion thresholds in locations where erosion events are widely separated in time. Measured values of R were low for our most vegetated sites and nearer unity for the sparsely vegetated site. 相似文献
6.
S I Reinke P J Ihrke J D Reinke A A Stannard S S Jang D M Gillette K W Hallock 《Journal of the American Veterinary Medical Association》1986,189(4):446-448
Actinomycotic mycetoma, a chronic, progressive infection of the subcutaneous tissue characterized by tumefaction, draining sinuses, and grains, was diagnosed in the right hindlimb of a young adult, male cat. The organisms that cause actinomycetoma are soil or plant saprophytes that gain entrance to the skin through abrasion or traumatic implantation. Streptomyces griseus, an organism generally considered to be a saprophyte, was cultured bacteriologically. Despite extensive surgery and long-term antibiotic therapy, the infection persisted, and the cat was euthanatized. 相似文献
7.
Gillette R 《Science (New York, N.Y.)》1971,172(3989):1215-1216
8.
Gillette R 《Science (New York, N.Y.)》1972,177(4055):1172-1175
9.
10.
Gillette R 《Science (New York, N.Y.)》1974,184(4137):650-651