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151.
P Santos A Chaveiro N Simões F Moreira da Silva 《Reproduction in domestic animals》2008,43(6):685-689
In the present study, the effect of bovine oocyte quality related to ultrastructural characteristics of zona pellucida (ZP), polyspermic penetration and embryo developmental competence was evaluated. Cumulus–oocyte complexes were punctioned from 453 ovaries, classified as 1, 2, 3 and 4 according to their morphological aspect, matured for 24 h and then divided into two groups. In group A, oocytes were fixed in 2.5% glutaraldehyde and 0.1 m sodium cacodylate and examined under a scanning electron microscope. Photomicrographs were taken and ZP’s pores were evaluated in squares of 6.4‐μm width. In group B, oocytes were fertilized in vitro. After 48 h, non‐cleaved oocytes were fixed for polyspermy evaluation. On days 7, 9 and 10, embryos were classified as developed (blastocysts and hatched blastocysts). Results showed that quality 1 oocytes revealed a ZP pore diameter of 0.50 ± 0.07 μm, which was smaller than the observed on oocytes of quality 2 (0.83 ± 0.10 μm), quality 3 (1.02 ± 0.22 μm) and quality 4 (1.38 ± 0.59 μm) (p ≤ 0.05). For In Vitro Fertilization (IVF), results showed that embryos originating from oocytes classed as 3 and 4 had lower cleavage rate (68.4% and 43.8%) than those belonging to class 1 and 2 (79.5% and 69.3%) (p ≤ 0.05). None oocyte classified as 3 and 4 developed to hatch blastocysts, while for oocytes belonging to quality 1 and 2, these values were, respectively, 15.2% and 12.5%. Concerning polyspermy, oocytes class 1 and 2 had lower polyspermic penetration than those belonging to class 3 and 4 (respectively 4.1%, 4.5%, 11.1% and 9.8%, for class 1, 2, 3 and 4). In conclusion, the present study demonstrated that oocytes with low qualities result in lower developmental competence and with high percentage of polyspermy after IVF, which can be the result of the ZP structure such as the number and the pore’s diameter. 相似文献
152.
153.
Alexandra Dixon Annie Chen John H. Rossmeisl Beverly Sturges Karen Vernau Jonathan M. Levine Arturo Otamendi Peter Early Alix Partnow Lara Curtis Stephanie Thomovsky Rebecca A. Packer Daniela A. Mauler 《Veterinary and comparative oncology》2019,17(4):472-478
Vertebral osteosarcoma (OSA) is the most common primary vertebral tumor in dogs, however studies examining the survival time after surgical decompression of these tumors are limited. There is also limited information regarding the benefit of adjunctive treatments such as radiation therapy or chemotherapy in these patients. The goal of this study was to determine survival time of dogs with primary vertebral OSA after palliative decompressive surgery alone and combined with radiation therapy and/or chemotherapy. Records from 22 client‐owned dogs diagnosed with primary vertebral OSA and treated with decompressive surgery were collected retrospectively from eight referral institutions. Survival time was assessed for dogs treated with surgery alone as well as dogs who received adjunctive radiation therapy and/or chemotherapy. Median survival time in the 12 dogs treated with surgery alone was 42 days (range: 3‐1333 days). The three dogs treated with surgery and chemotherapy had a median survival time of 82 days (range: 56‐305 days). Only one dog was treated with surgery and radiation therapy; this dog survived 101 days. Six dogs were treated with surgery, radiation therapy and chemotherapy; these dogs had a median survival time of 261 days (range: 223‐653 days). Cause of death in all cases that survived the initial postoperative period was euthanasia secondary to confirmed or suspected tumor regrowth. The results of this study suggest that definitive radiation therapy, possibly combined with concurrent chemotherapy, significantly improves survival in dogs treated with palliative decompressive surgery for vertebral OSA and should be the treatment of choice in selected cases. 相似文献
154.
Daphne W. Goldberg Miriam R. Fernandes Fbio P. Sellera Daniela G. C. Costa Ana Paula Loureiro Bracarense Nilton Lincopan 《Zoonoses and public health》2019,66(5):540-545
CTX‐M‐type extended‐spectrum β‐lactamase (ESBL)‐producing Enterobacteriaceae have become identified in marine ecosystem constituting a serious ecological issue. In this respect, although contamination of coastal waters and seafood, and even colonization of seabirds and fishes have been increasingly reported, molecular data are lacking to elucidate the clinical impact of ESBL producers in infected marine animals. In this study, using a genomic approach, we have analysed the genetic background of CTX‐M‐15‐producing Enterobacter hormaechei (belonging to the international human clone ST114) and Citrobacter freundii (ST265) co‐infecting a free‐living green turtle (Chelonia mydas) suffering from septic arthritis, which progressed to generalized coelomitis and death. Wide resistome of these pathogens contributed to treatment failure and death of the animal. 相似文献
155.
Figueiredo JP Cruz ML Mendes GM Marucio RL Riccó CH Campagnol D 《Veterinary anaesthesia and analgesia》2008,35(6):511-518
ObjectiveTo assess the brachial plexus block in chickens by an axillary approach and using a peripheral nerve stimulator.Study designProspective, randomized, double-blinded study.AnimalsSix, 84-week old, female chickens.MethodsMidazolam (1 mg kg−1) and butorphanol (1 mg kg−1) were administered into the pectoralis muscle. Fifteen minutes later, the birds were positioned in lateral recumbency and following palpation of the anatomic landmarks, a catheter was inserted using an axillary approach to the brachial plexus. Lidocaine or bupivacaine (1 mL kg−1) was injected after plexus localization by the nerve stimulator. Sensory function was tested before and after blockade (carpus, radius/ulna, humerus and pectoralis muscle) in the blocked and unblocked wings. The latency to onset of motor and sensory block and the duration of sensory block were recorded. A Friedman nonparametric one-way repeated-measures anova was used to compare scores from baseline values over time and to compare the differences between wings at each time point.ResultsA total of 18 blocks were performed with a success rate of 66.6% (12/18). The latency for motor block was 2.8 ± 1.1 and 3.2 ± 0.4 minutes for lidocaine and bupivacaine, respectively. The latencies for and durations of the sensory block were 6.0 ± 2.5 and 64.0 ± 18.0 and 7.8 ± 5.8 and 91.6 ± 61.7 minutes for lidocaine and bupivacaine, respectively. There was no statistical difference between these times for lidocaine or bupivacaine. Sensory function was not abolished in nonblocked wings.Conclusions and clinical relevanceThe brachial plexus block was an easy technique to perform but had a high failure rate. It might be useful for providing anesthesia or postoperative analgesia of the wing in chickens and exotic avian species that have similar wing anatomy. 相似文献
156.
Luiz Sergio Almeida Camargo Fernanda Queiros Costa Michele Munk Sabine Wohlres‐Viana Raquel Varela Serapio Bruno Campos Carvalho Paulo Henrique Campos Alex Cabral Vieira Luiz Altamiro Garcia Nogueira Joao Henrique Moreira Viana 《Reproduction in domestic animals》2019,54(10):1357-1365
This study investigated the influence of heat shock during in vitro maturation on embryo development following in vitro fertilization (IVF) or parthenogenesis (Part). Immature bovine cumulus–oocyte complexes were exposed to heat shock (41.0°C) during the first 12 hr of in vitro maturation (IVM), followed by 12 hr at 38.5°C. Control group consisted of in vitro maturation for 24 hr at 38.5°C. Oocytes were in vitro‐fertilized or activated with ionomycin and cultured in vitro for 192 hr post‐in vitro insemination or parthenogenetic activation (hpia). There was an interaction (p < .01) between temperature of IVM and method of oocyte activation (IVF or Part) for cleavage at 48 hpia. Heat shock had a negative impact (p < .01) on cleavage of IVF embryos, whereas no (p > .05) effect was found in the Part embryos. Embryo development towards blastocyst stage at 168 and 192 hpia decreased in both IVF and Part embryos derived from heat‐shocked oocytes. Heat shock increased (p < .05) the apoptotic index in Part blastocysts, but no effect (p > .05) was found in IVF counterparts. Heat shock also down‐regulated the expression of AQP3 (p < .01) and up‐regulated the expression of HSP70.1 (p < .01) in Part blastocysts, whereas it down‐regulated the expression of ATP1A1 (p < .05) in IVF blastocysts. In conclusion, the effects of heat shock during IVM on early embryo cleavage and blastocyst apoptosis are influenced by the method of oocyte activation and expression of some genes can be disturbed in embryos derived from heat‐shocked oocytes. 相似文献
157.
de Melo Rafaela Leitão Correia Dutra Júnior Wilson Moreira Palhares Liliane Olímpio de Moura Ferreira Débora Nathália de Aquino Rafael Santos Cordeiro Manso Helena Emília Cavalcanti 《Tropical animal health and production》2019,51(5):1057-1063
Tropical Animal Health and Production - The objective of this study was to evaluate the biochemical, behavioral, and physiological parameters in pregnant sows of native and improved crossbreeds... 相似文献
158.
Dorothea Besselmann Daniela Schaub Christian Wenker Jürg V?llm Nadia Robert Claude Schelling Hanspeter Steinmetz Marcus Clauss 《Journal of zoo and wildlife medicine》2008,39(1):86-91
Since 1956, when the Basle Zoo (Switzerland) initiated the breeding of lesser kudu (Tragelaphus imberbis), 43% of the lesser kudu juveniles died before reaching an age of 6 mo. In this study, the objective was to obtain the pathological findings, nutritional history, and family tree information in order to evaluate the influence of husbandry on juvenile mortality in these animals. The main cause of death was white muscle disease (WMD), diagnosed in 14 cases (26%) of the deceased juveniles. Although enclosure size had remained constant and animal accessibility to the public was constantly high, both herd size and juvenile mortality had increased from 1956-2004. The diet consumed by the whole group in 2004 had deficient levels of vitamin E and selenium. The increasing linear trend of the mortality rate since the 1960s was significant, and there was a significant correlation between herd size and overall juvenile mortality. In contrast, there was no correlation between herd size and the occurrence of juvenile mortality associated specifically with WMD. Other investigated factors (sex, inbreeding, and season) had no significant effect on overall mortality up to 6 mo of age or on mortality associated with WMD. These results characterize both a dietary and a husbandry problem, and are supported by a lack of similar juvenile mortality in another facility where the diet was supplemented with vitamin E, animal numbers were kept low, and the enclosure structure offered more retreat options for the animals. 相似文献
159.
Gabriela Noronha de Toledo Pamela Rodrigues Reina Moreira Daniele Santos Rolemberg Andréia Coutinho Facin Julio Edward Hough Monteiro Mareliza Possa de Menezes Maria Eduarda Bastos Andrade Moutinho da Conceição Felipe Augusto Ruiz Sueiro Rosemeri de Oliveira Vasconcelos Paola de Castro Moraes Mirela Tinucci Costa Andrigo Barboza de Nardi 《Topics in companion animal medicine》2018,33(2):35-39
Osteosarcoma is the most commonly reported bone tumor in dogs, typically affecting the axial and appendicular skeleton. Involvement of the paranasal sinuses and the nasal cavity is extremely rare. This report describes a 6-year-old, female, cross-breed dog presented with signs of 90 days duration and diagnosed with a mass located in the right nasal cavity. Radiography, rhinoscopy, and computed tomography findings suggested the presence of an intranasal tumor. Osteosarcoma in the nasal cavity was diagnosed based on histopathological examination and clinical and imaging findings. Survival time was 12 months from diagnosis. 相似文献
160.
Raquel P. F. Guiné Susana Matos Fernando J. Gonçalves Daniela Costa Mateus Mendes 《International Journal of Fruit Science》2018,18(2):199-214
ABSTRACTThe study aimed at evaluating the influence of different production conditions, conservation, and extraction procedures on the total phenolic compounds and antioxidant activity of blueberries by DPPH and ABTS methods. The production factors considered were origin, altitude of the farm location, and age of the bushes. The conservation conditions considered were freezing as opposed to the fresh product. The extraction procedures included two different solvents and two orders of extraction. The data analysis was carried out by training artificial neural networks to model the data and extract information from the model.The results obtained revealed that the type of extract and the order of extraction influenced the concentrations of phenolic compounds as well as the antioxidant activity of the different samples studied. Also the origin of the farms from where the blueberries were harvested significantly influence those properties, showing that the blueberries from Oliveira do Hospital had less phenolic compounds and lower antioxidant activity. Also older bushes at higher altitudes seem to produce berries richer in these properties. Regarding conservation, no influence was observed for phenols but a slight influence could be detected for antioxidant activity. 相似文献