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51.
Canada N Meireles CS Rocha A Sousa S Thompson G Dubey JP Romand S Thulliez P Correia da Costa JM 《Veterinary parasitology》2002,110(1-2):11-15
Neospora caninum was isolated from the brain of an aborted 4-month-old fetus from a dairy cow herd with endemic neosporosis in Porto, Portugal. The fetal brain homogenate was inoculated interperitoneally first into outbred Swiss Webster mice given dexamethasone and then the peritoneal exudates from these mice was co-inoculated with mouse sarcoma cells in the peritoneal cavity of mice given dexamethasone. N. caninum tachyzoites were seen in peritoneal exudate of the second passage. Tachyzoites from the peritoneal exudate reacted positively with anti-N. caninum antibodies and not with anti-Toxoplasma gondii antibodies and contained N. caninum specific DNA. This Portuguese isolate of N. caninum has been successfully maintained in cell culture. The dam of the aborted fetus had an antibody titer of 1:10240 in the Neospora agglutination test (NAT). Antibodies to N. caninum were found in 76 of 106 cows from this herd in titers of 1:40 in 31, 1:80 in 22, > or =1:160 or more in 23 in the Neospora agglutination test. This is the first isolation of a viable N. caninum-like parasite from any host in Portugal. 相似文献
52.
Batista M González F Cabrera F Palomino E Castellano E Calero P Gracia A 《The Canadian veterinary journal. La revue veterinaire canadienne》2000,41(7):562-564
Anatomical, behavioral, histological, endocrinological, and cytogenetic characteristics were determined in a horned intersex goat. Histology of the gonads confirmed that the goat was a true hermaphrodite. Cytogenetic analysis showed that it was a chimera (60XX/60XY). Use of laparoscopy allowed determination of characteristics of the internal gonads. 相似文献
53.
Costa CA Vieira LD Berne ME Silva MU Guidoni AL Figueiredo EA 《Veterinary parasitology》2000,88(1-2):153-158
The variability between and within breeds with respect to nematode egg counts (EPG), packed cell volume (PCV) and hemoglobin (Hb) was studied in 36 yearling female goats of the Caninde (15), Bhuj (6) and Anglo-Nubian (15) breeds, exposed to Haemonchus contortus. Nematode-free goats were turned to a contaminated paddock in late February. From then on, fecal egg per gram counts (EPG), packed cell volume (PCV) and hemoglobin (Hb) were determined at 2-week intervals up to Week 18. The EPG, transformed as [log(EPG + 75)], varied (P < 0.01) between goats within breeds and between weeks of exposure, but not between goat breeds (P > 0.05). PCV and Hb were affected by goat breeds (P < 0.05), by goats within breeds (P < 0.01) and by weeks of exposure (P < 0.01). Anglo-Nubians had higher (P < 0.01) PCV and Hb than Caninde; Bhuj had intermediate values. There were two EPG rises; one between Weeks 6 and 10 and the other between Weeks 14 and 16. The within breed variability was marked during the EPG rise on Week 6, when individual egg counts ranged from 130 to 2500. The EPG rises coincided with drops in Hb. PCV presented a similar trend, though not as marked. Haemonchus was responsible for more than 95% of nematode eggs counted. Considering the goat as experimental unit, the correlation coefficients (r) were: -0.45, P = 0.0064, between log(EPG + 75) and PCV; and -0.53, P = 0.0009, between log(EPG + 75) and Hb. The negative correlation between egg counts and blood values suggested breed differences in PCV and Hb were related to resistance to H. contortus infection and/or to its effects. 相似文献
54.
Sousa Larissa Nascimento Batista Samira Pereira Silva Samara Santos da Silva Rômulo Fylipe Sarmento Wlysse Ferreira Mota Rinaldo Aparecido Brasil Arthur Willian Lima Amaku Marcos Feitosa Thais Ferreira Vilela Vinícius Longo Ribeiro 《Veterinary research communications》2022,46(2):507-515
Veterinary Research Communications - This study aimed to describe the transmission of T. gondii in naturally infected goats in the semiarid region of northeastern Brazil, through evaluating the... 相似文献
55.
ent-Pimara-8(14),15-dien-19-oic acid (PA) isolated from Viguiera arenaria (Asteraceae; Heliantheae) inhibited rat carotid rings contraction induced by phenylephrine (10(-8) mol/l) or potassium chloride (45 mmol/l) at concentration ranging from 5 to 20 microg/ml. This inhibitory effect was not reversible after the removal of this compound from the medium bath. 相似文献
56.
57.
ent-kaurenoic acid (KA) isolated from Viguiera robusta was tested for activity on vascular smooth muscle contactility. Cumulative concentration-response curves were obtained for a stepwise increase (10(-10)-10(-05) mol/l) in the concentration of phenylephrine (Phe), a selective alpha(1)-adrenergic agonist. The effects in the presence of KA (0.2, 2.0 and 20.0 microg/ml), and 90 min after the removal of KA from the medium bath were compared to controls. At 20.0 microg/ml, KA inhibited the in vitro contractility of rat carotid artery elicited by Phe, but had no effect at lower concentrations (0.2 and 2.0 microg/ml). The effect elicited by KA was reversible after 90 minutes. 相似文献
58.
59.
Cryopreservation of Piau‐Breed Wild Boar Sperm: Assessment of Cooling Curves and Centrifugation Regimes 下载免费PDF全文
HH Shiomi RO Pinho DMA Lima JB Siqueira MCR Santos EV Costa PS Lopes SEF Guimarães JD Guimarães 《Reproduction in domestic animals》2015,50(4):545-553
This study aimed to assess the effects of different cooling curves and centrifugation regimes used in cryopreservation protocols on the post‐thaw viability of Piau‐breed wild boar (Sus scrofa) sperm using in vitro assessment tests. Two centrifugations (800 g for 10 min and 2400 g for 3 min) and two cooling curves (conventional cooling using nitrogen vapour – freezing 1 and automated cooling using a programmed freezing machine – freezing 2) were tested. Therefore, the treatments were divided into M3 – centrifugation at 2400 g for 3 min and freezing 2; M10 – centrifugation at 800 g for 10 min and freezing 2; R3 – centrifugation at 2400 g for 3 min and freezing 1; and R10 – centrifugation at 800 g for 10 min and freezing 1. No significant differences (p > 0.05) between treatments occurred post‐thawing regarding the total sperm motility means recorded. The mean values of the different treatments were not different from each other regarding the supravital staining (SV), hypo‐osmotic test (HO), sperm–egg binding assay or sperm morphology. This study showed that both the cooling curve and the centrifugation regime affected the quality of post‐thaw sperm, and centrifugation for shorter times and cooling curves using automated cooling are the most suitable for minimizing sperm injury. 相似文献
60.
The value of molecular expression of KIT and KIT ligand analysed using real‐time polymerase chain reaction and immunohistochemistry as a prognostic indicator for canine cutaneous mast cell tumours 下载免费PDF全文
T. A. Costa Casagrande L. M. de Oliveira Barros H. Fukumasu B. Cogliati L. M. Chaible M. L. Z. Dagli J. M. Matera 《Veterinary and comparative oncology》2015,13(1):1-10
This study investigated the correlation between KIT gene expression determined by immunohistochemistry and real‐time polymerase chain reaction (RT‐PCR) and the rate of tumour recurrence and tumour‐related deaths in dogs affected with mast cell tumour (MCT). Kaplan–Meier curves were constructed to compare tumour recurrence and tumour‐related death between patients. The log‐rank test was used to check for significant differences between curves. KIT‐I, KIT‐II and KIT‐III staining patterns were observed in 9 (11.11%), 50 (61.73%) and 22 (27.16%) tumours, respectively. Tumour recurrence rates and tumour‐related deaths were not associated with KIT staining patterns (P = 0278, P > 0.05), KIT (P = 0.289, P > 0.05) or KIT ligand (P = 0.106, P > 0.05) gene expression. Despite the lack of association between KIT staining pattern and patient survival time, the results suggest a correlation between aberrant KIT localization and increased proliferative activity of MCTs. RT‐PCR seems to be a sensible method for quantitative detection of KIT gene expression in canine MCT, although expressions levels are not correlated with prognosis. 相似文献