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421.
Jaqueline B. Azevedo Gustavo S. Silva Priscylla S. Rocha Letícia C. Pitchenin Valéria Dutra Luciano Nakazato Anderson Castro Soares de Oliveira Caroline A. Pescador 《Tropical animal health and production》2017,49(2):311-316
Ureaplasma diversum infection in bovine females may result in various reproductive problems, including granular vulvovaginitis, abortion, weak calves, salpingitis, and spontaneous abortion. The presence of U. diversum in a dairy bovine population from midwestern Brazil has not been established. The aim of this study was to determine whether U. diversum was present in dairy cattle from midwestern Brazil using polymerase chain reaction (PCR). Vulvovaginal mucus was analyzed from 203 cows located in six municipalities in the north region of Mato Grosso State, Brazil. A total of 25% of dairy cows with vulvovaginitis were positive for U. diversum. The factors evaluated were included in a multivariable logistic regression model with the presence of at least one positive cow in the herd serving as the dependent variable. Three variables were significantly associated with a U. diversum-positive PCR and were included in the final multivariable model: number of parities, vulvar lesions, and reproductive problems. For each new parity, the chance of U. diversum infection decreased 0.03-fold, indicating that cows with the highest number of parities were more protected. The presence of vulvar lesions was increased 17.6-fold in females positive for U. diversum, suggesting that this bacterium could be related to the red granular lesions in the vulvar mucosa, whereas reproductive problems were increased 7.6-fold. However, further investigations should be conducted to ascertain the effects of U. diversum in association with other mycoplasma species in the herds studied. 相似文献
422.
Transporting bovine oocytes in a medium supplemented with different macromolecules and antioxidants: Effects on nuclear and cytoplasmic maturation and embryonic development in vitro
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M Ambrogi PC Dall'Acqua NAS Rocha‐Frigoni BCS Leão GZ Mingoti 《Reproduction in domestic animals》2017,52(3):409-421
We investigated whether supplementing the medium used to transport bovine oocytes with different macromolecules [foetal calf serum (FCS) or bovine serum albumin (BSA)] or a mixture of antioxidants (cysteine, cysteamine and catalase) affects their nuclear and cytoplasmic maturation and thereby affects their subsequent embryonic development and cryotolerance. Oocytes were transported for 6 hr in a portable incubator and then subjected to standard in vitro maturation (IVM) for 18 hr. The oocytes in the control groups were cultured (standard IVM) for 24 hr in medium containing 10% FCS (Control FCS) or 10% FCS and the antioxidant mixture (Control FCS+Antiox). The intracellular concentrations of reactive oxygen species (ROS) at the end of IVM period were lower in the oocytes subjected to simulated transport in the presence of a macromolecular supplement or the antioxidant mixture than that of the control group (FCS: 0.62 and BSA: 0.66 vs. Control FCS: 1.00, p < .05; and Transp: 0.58 and Transp Antiox: 0.70 vs. Control FCS: 1.00, p < .05). After IVM, the mitochondrial membrane potentials of the transported oocytes were lower than those of the non‐transported oocytes (FCS: 0.41 and BSA: 0.57 vs. Control FCS: 1.00, p < .05; and Transp: 0.48 and Transp Antiox: 0.51 vs. Control FCS: 1.00 and Control Antiox: 0.84, p < .05). The blastocyst formation rates (36.9% average) and the re‐expansion rates of vitrified‐warmed blastocysts (53%, average) were unaffected (p > .05) by the treatments. In conclusion, supplementing the medium in which bovine oocytes are transported with antioxidants or different macromolecules did not affect their in vitro production of embryos or their cryotolerance. 相似文献
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Vinícius Fernandes Canassa Edson Luiz Lopes Baldin José Paulo Franco Bentivenha Luiz Eduardo da Rocha Pannuti André Luiz Lourenção 《国际虫害防治杂志》2017,63(2):112-118
Soybeans are of great importance in the world agricultural landscape, and their productive potential is significantly reduced by attacks from insect pests. Factors such as the expansion of national agricultural regions, together with no-tillage management and “off-season” maize cultivation, have favored the increase of secondary species such as Dichelops melacanthus (Dallas) (Hemiptera: Pentatomidae), intensifying the damage caused by the soybean stink bug complex. The use of resistant genotypes may be a valuable strategy as an alternative to the excessive use of chemical control in crops. This study evaluated the attractiveness and feeding preferences of the green-belly stink bug in 17 soybean genotypes in different maturity groups (early, semiearly, and late) to characterize the expression of antixenosis resistance. To this end, free-choice tests of attractiveness and food preference were performed under laboratory conditions. The early genotypes PI 171451 and D 75-10169, the semiearly genotypes IAC 78-2318, “IAC 100”, IAC 74-2832, PI 227687, and “IAC 24” and the late genotypes PI 274454, PI 274453, and L 1-1-01 expressed significant levels of antixenosis against adult D. melacanthus. These results will be useful for soybean breeding programs focusing on the stink bug resistance complex. 相似文献
424.
H D Blackburn J L Rocha E P Figueiredo M E Berne L S Vieira A R Cavalcante J S Rosa 《Veterinary parasitology》1992,44(3-4):183-197
Weaned wether goats (n = 144) approximately 6 months of age were placed in a 2 x 3 factorial experiment to test the effects and interaction of two levels of nutrition (growth+maintenance, NUT1; and twice growth+maintenance, NUT2) and three levels of Haemonchus contortus burden (0, 500, and 2000 larvae administered every 2 weeks; W0, W500, and W2000, respectively) on packed cell volume, red blood cell count, total serum protein and leukocytes. The statistical analysis revealed clear and proportionate differences among levels of infection for all variables. A significant (P < 0.05) nutritional effect was also found associated with all the variables except leukocytes. Nutrition by worm load interactions were found for packed cell volume and leukocytes. The neutrophil/lymphocyte ratio was higher in the NUT1-infected animals, leading to the nutrition by worm load interaction for leukocytes. An analysis for the different leukocyte types revealed significant (P < 0.05) differences among infection levels for lymphocytes, while nutrition level was found to be a significant effect for basophil count and immature white cells. Several significant correlations were observed between pairs of variables. Faecal egg output could be predicted from actual worm count in three of the four necropsy periods. The clear differences observed for blood parameters were not present in production traits, suggesting that physiological thresholds may play an important role in framing the metabolic activity of biological organisms. Total serum protein was the best indicator of these effects on production parameters. 相似文献
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Objective To assess the effectiveness of cobalt pellets in maintaining adequate vitamin B12 in beef cows on pasture of low cobalt content.
Design A field experiment in a herd grazing cobalt deficient pasture.
Animals Mature Murray Grey cows.
Procedure Cows were given a single oral dose of 0, 1, 2 or 4 cobalt pellets (30 g pellets containing 30% by weight cobaltic oxide) with a selenium pellet and a grub screw. Samples of blood, liver, faeces and milk for chemical analyses were collected at intervals over a period of 2 years after treatment.
Results A single cobalt pellet raised liver vitamin B12 concentration of cows above that of untreated cows for at least 28 weeks, and 2 or 4 pellets for 57 weeks. Plasma vitamin B12 concentration was an unreliable indicator of the effectiveness of cobalt pellet therapy. Milk vitamin B12 and faecal cobalt concentrations increased in response to cobalt pellet therapy.
Conclusion These studies show that one cobalt pellet will prevent vitamin B12 inadequacy in beef cows for between 28 and 57 weeks; two or four pellets will prevent inadequacy for 57 to 75 weeks. Milk vitamin B12 concentration may be a useful indicator of the effectiveness of cobalt pellets in increasing the vitamin B12 supply in lactating cows. 相似文献
Design A field experiment in a herd grazing cobalt deficient pasture.
Animals Mature Murray Grey cows.
Procedure Cows were given a single oral dose of 0, 1, 2 or 4 cobalt pellets (30 g pellets containing 30% by weight cobaltic oxide) with a selenium pellet and a grub screw. Samples of blood, liver, faeces and milk for chemical analyses were collected at intervals over a period of 2 years after treatment.
Results A single cobalt pellet raised liver vitamin B
Conclusion These studies show that one cobalt pellet will prevent vitamin B
427.
Protein G expression and cell-to-cell fusion of cells transfected with the G gene of viral haemorrhagic septicaemia virus (VHSV) has been characterised. The presence of protein G in the membrane of transfected cells was confirmed by staining with Abs (Abs) and FACS. The subsequent formation of syncytia by membrane fusion of transfected cells required transfection with a wild type G gene and a low pH step. Mice Abs made against the protein G regions involved in fusion and neutralising monoclonal Abs (MAbs) as well as MAbs against some linear epitopes inhibited syncytia formation, thus confirming that syncytia formation was G-dependent. Similarly, Abs from trout immunised with purified VHSV or protein G inhibited syncytia formation whereas Abs from non-immunised or non-infected animals did not. Abs from mice or trout with the highest neutralisation titres also showed the highest percentage of inhibition of syncytia. While the main utility of these observations might be to further the understanding of the complex trout antibody response against VHSV and in the follow up of VHSV immunisation attempts, they may also have some future diagnostic potential for countries were work with VHSV is not allowed. 相似文献
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Rocha TA Mauldin GN Patnaik AK Bergman PJ 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2000,14(5):486-490
Medical records and biopsy specimens were retrospectively reviewed from 25 dogs diagnosed with unresectable urinary bladder carcinoma and treated with chemotherapy. Our intention was to identify clinical, histologic, and immunohistochemical indicators of prognosis. Immunohistochemical stains for P-glycoprotein, glutathione-S-transferase pi, and factor VIII-related antigen were applied to archived tissue. There were more spayed female dogs than castrated male dogs (76% versus 24%). Transitional cell carcinoma was the most common tumor (88%, n = 22), followed by undifferentiated carcinoma (8%, n = 2) and squamous cell carcinoma (4%, n = 1). Overall median survival was 251 days. Histologic diagnosis and immunohistochemical characteristics did not correlate with prognosis. Spayed females survived significantly longer than castrated males (358 days versus 145 days, P = .042). Dogs that received either doxorubicin or mitoxantrone in addition to a platinum-based chemotherapeutic (either cisplatin or carboplatin) lived significantly longer than those that received only a platinum compound (358 days versus 132 days, P = .042). 相似文献