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排序方式: 共有112条查询结果,搜索用时 390 毫秒
31.
KL Jensen L Krag GB Boe‐Hansen HE Jensen H Lehn‐Jensen 《Reproduction in domestic animals》2008,43(6):760-763
Tumours are rare in the bovine testicle. A case of malignant Sertoli cell tumour in a 29‐month‐old Simmenthal bull that was hospitalized with a history of severe unilateral scrotal swelling is reported. On inspection and palpation, the scrotal sac was found enlarged with fluctuant content in the right side. The right testicle was enlarged, hard and indolent. Also the right plexus pampiniformis and funiculus spermaticus were enlarged. Sonograms revealed severe changes in the right testicle with a loss of homogeneity and multiple hyperechogenic areas. After slaughter, the scrotum with testicles were removed and evaluated pathologically. On section, the right testicle contained areas of necrosis, haemorrhage, and mineralization. Histology showed Sertoli cells in tubular structures surrounded by dense fibrous stroma replacing normal testicular tissue. Both lymphatic and blood vessels were infiltrated by neoplastic cells. Immunohistochemically, the neoplastic cells stained positive for vimentin and negative for cytokeratin and S‐100. Based on the pathological observations a diagnosis of right‐sided malignant Sertoli cell tumour with vascular invasion and hydrocele was established. 相似文献
32.
We used egg break‐out and spermatozoa trapped in the perivitelline layer of eggs to test the hypothesis that sperm supply and egg fertilization rate are high in the ostrich. Egg fertilization status was determined at break‐out by the appearance of the germinal disc (GD) and then the perivitelline layer overlying the GD region was collected to count sperm (SpermOPVL) under fluorescence following staining with 4′,6′‐diamidino‐2‐phenyindole (DAPI). The study was carried out on commercial ostrich farms over two laying seasons. In the first year, 229 eggs from nine randomly chosen ostrich pens comprising pairs, trios (two females, one male) and larger groups were collected for 1 week of every month of laying. Eggs contained 253 ± 18 SpermOPVL/mm2 of the GD (mean ± SEM; range 0–1330). Egg fertilization rate averaged 89.4 ± 3.4% and varied from 78.6 to 98.2% between pens. Month had no effect on sperm supply or egg fertilization status. Eggs from paired birds (sex ratio 1 : 1) had less sperm in the GD than the eggs from pens with a higher sex ratio. In the second year, 150 eggs from seven pens, each containing only one male and either one, two or three females, were studied for 2 weeks at the beginning (winter), middle (spring) and end (summer) of laying. Eggs contained 364 ± 45 SpermOPVL/mm2 of the GD (range 0–2880). Season had no effect on sperm supply or egg fertilization. The number of SpermOPVL varied between pens, assumed to be due to variation between individual males. The number of SpermOPVL increased as the sex ratio increased only when very high‐ranking males were excluded from the analysis. Egg fertilization rate was 94.4 ± 3.1% but varied from 64.0 to 100% between pens. Egg fertilization was not affected by season or sex ratio. Low fertilization rates were observed in two pens and appeared related to the lack of synchrony between timing of laying and sperm production in the first, and lack of mating in the second pen. We conclude that ostrich flocks generally have high rates of egg fertilization and any infertility is associated with lack of sperm supply. 相似文献
33.
为了观察促排卵素3号(LRH-A3)对母猪繁殖性能的作用和效果,发情母猪配种前4—6h,用LRH-A3进行处理,并与不使用激素的发情母猪进行比较。结果地方品种母猪的受胎率、平均产仔数、仔猪成活率分别为93.3%、14.6头和89.5%。与对照组相比,母猪受胎率无显著差异(P〉0.05),平均产仔数显著高于对照组(P〈0.01),仔猪成活率比对照组低4.6%,差异显著(P〈0.01)。经产瘦肉型母猪的配种受胎率、平均产仔数、仔猪成活率分别为86.7%,12.3头和93.8%,与对照组相比,配种受胎率、仔猪成活率无显著性差异(P〉0.05),母猪平均产仔数显著高于对照组(P〈0.01)。青年瘦肉型母猪的配种受胎率、平均产仔数、仔猪成活率分别为83.3%、10.6头和94.5%,与对照组相比,母猪的配种受胎率、平均产仔数均显著高于对照组(P〈0.01),仔猪成活率与对照组无显著差异(P〉0.05)。试验结果表明,发情母猪配种前肌注LRH-A3后,青年瘦肉型母猪繁殖效果最理想,经产瘦肉型母猪次之,地方品种母猪不理想。 相似文献
34.
R. J. HUNT dvm ms D. ALLEN dvm ms Diplomate acvs G. M. BAXTER dvm ms Diplomate acvs B. R. JACKMAN dvm A. H. PARKS MA VET MB MRCVS Diplomate ACVS 《Veterinary surgery : VS》1991,20(1):15-20
Deep digital flexor tendon transection at the mid-metacarpus was performed in 20 horses with severe acute or chronic laminitis that was not responsive to conventional treatment. Sixteen horses improved within 72 hours, one horse worsened, and two horses were unaffected by the surgery. Eleven horses survived less than 1 month after surgery and six horses survived longer than 6 months. Three horses surviving longer than 6 months have remained lame and no horse has returned to athletic performance. Transection of the deep digital flexor tendon at the mid-metacarpus may decrease the pain associated with the acute refractory stage of laminitis and may be useful as an immediate salvage procedure; however, despite the early clinical improvement observed after tenotomy, the survival rate of affected horses may not be altered. 相似文献
35.
Matthew DEAN Jason HUNT Lisa MCDOUGALL Jack ROSE 《The Journal of reproduction and development》2014,60(6):438-446
We have determined uterine glycogen content, metabolizing enzyme expression and activity in the mink, a species that exhibits obligatory embryonic diapause, resulting in delayed implantation. Gross uterine glycogen concentrations were highest in estrus, decreased 50% by diapause and 90% in pregnancy (P ≤ 0.05). Endometrial glycogen deposits, which localized primarily to glandular and luminal epithelia, decreased 99% between estrus and diapause (P ≤ 0.05) and were nearly undetectable in pregnancy. Glycogen synthase and phosphorylase proteins were most abundant in the glandular epithelia. Glycogen phosphorylase activity (total) in uterine homogenates was higher during estrus and diapause, than pregnancy. While glycogen phosphorylase protein was detected during estrus and diapause, glycogen synthase was almost undetectable after estrus, which probably contributed to a higher glycogenolysis / glycogenesis ratio during diapause. Uterine glucose-6-phosphatase 3 gene
expression was greater during diapause, when compared to estrus (P ≤ 0.05) and supports the hypothesis that glucose-6-phosphate resulting from phosphorylase activity was dephosphorylated in preparation for export into the uterine lumen. The relatively high amount of hexokinase-1 protein detected in the luminal epithelia during estrus and diapause may have contributed to glucose trapping after endometrial glycogen reserves were depleted. Collectively, our findings suggest to us that endometrial glycogen reserves may be an important source of energy, supporting uterine and conceptus metabolism up to the diapausing blastocyst stage. As a result, the size of uterine glycogen reserves accumulated prior to mating may in part, determine the number of embryos that survive to the blastocyst stage, and ultimately litter size. 相似文献
36.
Marine environment of the eastern and central Aleutian Islands 总被引:2,自引:0,他引:2
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38.
DAVID A. HUNT DVM JACK R. SNYDER DVM PhD DiplomateACVS JOE P. MORGAN DVM Vet Med Dr DiplomateACVR SUSAN M. STOVER DVM PhD DiplomateACVs ROY R. POOL DVM PhD JOHN R. PASCOE BVSC PhD 《Veterinary surgery : VS》1990,19(2):107-116
Femoral neck and proximal epiphyseal lengths were measured in 37 femurs from 19 cadaver foals that were 1 day to 12 months old to determine the applicability of a human interfragmentary compression system to equine femoral capital physeal fractures. Because components of the implant system are available only in fixed sizes, its use was possible in foals older than 5 weeks of age, but not in younger foals. The 135 degree angle plate conformed best to the equine femur. Femoral capital physeal fractures were created surgically and repaired with the implant system in three foals. Fracture stability was evident clinically and radiographically in all three foals until euthanasia at month 3. At necropsy, the treated femurs were 4, 8, and 27 mm shorter than their mates. Epiphyseal viability was verified in all three foals by tetracycline deposition and new appositional bone growth comparable with that in the contralateral control epiphyses. The treated capital physis was open but reduced in thickness in one foal, disorganized in one foal, and closed in one foal. Fixation by compression with the implant system resulted in stability sufficient for fracture healing and maintenance of epiphyseal viability, although it was associated with reduced longitudinal femoral growth. 相似文献
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