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21.
Thiago Luiz Da Mata Monique Inês SegerenAline Segeren Fonseca Carlos Augusto Colombo 《Scientia Horticulturae》2009
Genetic diversity was evaluated by RAPD markers and morpho-agronomic characters for a total of 42 accessions of Barberton daisy (Gerbera jamesonii) consisting of 29 commercial and 13 wild accessions. A total of 74 polymorphic bands were obtained employing a set of 12 primer pairs. The average genetic similarity coefficient for the 42 accessions, evaluated by Jaccard index was 0.55 ranging from 0.28 to 1.00. The genetic structure found among Barberton daisy accessions was evaluated by hierarchic classification analyses and UPGMA modeling, revealing six clusters of genotypes where two of them include the wild accessions and the remaining four including commercial material, except for wild genotype number 9. Shannon (H′) index was calculated using the molecular markers to investigate the genetic variation among the Gerbera accessions and showed higher values for the commercial cluster in comparison to the values obtained for the individuals from the non-commercial cluster, namely 0.34 versus 0.27, respectively. Therefore, both calculated indices (Jaccard and Shannon) indicated the presence of higher genetic variation among commercial accessions in comparison to the cluster representing non-commercial accessions, suggesting that genetic breeding programs may focus on commercial accessions to recombine interesting genotypes with commercially important and marketing-desired characteristics. 相似文献
22.
Cezinande Meira Valsair Matos Pessoa Jo?o Carlos Pinheiro Ferreira Gustavo Henrique M. Araujo Marilu M. Gioso Sony Dimas Bicudo Eunice Oba Cassia Orlandi 《Journal of veterinary science (Suw?n-si, Korea)》2006,7(4):387-390
The present study was conducted in order to verify the efficacy of lower doses and alternative routes of a prostaglandin F2α analogue, luprostiol (PGF), for the induction of luteolysis and the precipitation of estrus in nonlactating Nelore cows (Bos taurus indicus). A conventional dose (15 mg) of PGF was compared to doses lower than the conventional dose, which ranges from 10 to 50%, that were administered intramuscularly (IM), intravulvosubmucosally (IVSM), or in the Bai-hui acupuncture site located within the lumbosacral area. The cows were administered PGF 8 day after estrus in the presence of a corpus luteum, and randomly assigned to the following groups: G1 (positive control), 15 mg, IM (n = 23); G2, 7.5 mg, IM (n = 23); G3, 3.75 mg, IM (n = 24); G4, 7.5 mg, IVSM (n = 25); G5, 3.75 mg, Bai-hui acupoint (n = 24); and G6, 1.5 mg, Bai-hui acupoint (n = 25). The results indicated that 50% of a conventional dose of PGF (7.5 mg) resulted in a complete luteal regression (plasma progesterone <1 ng/ml) at Hour 48, and hastened estrus, regardless of whether or not PGF was administered IM or IVSM. Comparatively, 10 or 25% of the conventional dose, even when administered to the Bai-hui acupoint, resulted in an initial reduction in the concentration of progesterone at Hour 24, followed by an increase observed at Hour 48. In conclusion, 25% of a conventional PGF dose administered via the Bai-hui acupoint proved inadequate to induce a complete luteal regression, whereas 50% of a conventional dose administered IM or IVSM was found to be the minimal dose required to induce effectively a complete luteal regression, and to precipitate the onset of estrus in nonlactating Nelore cows. 相似文献
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24.
Assessment of regional systolic and diastolic myocardial function using tissue Doppler and strain imaging in dogs with dilated cardiomyopathy 总被引:1,自引:0,他引:1
Chetboul V Gouni V Sampedrano CC Tissier R Serres F Pouchelon JL 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(4):719-730
BACKGROUND: Tissue Doppler Imaging (TDI) or strain (St) imaging could provide sensitive indices for early detection and treatment follow-up of canine dilated cardiomyopathy (DCM). Analysis of TDI and St features in dogs with overt DCM is a prerequisite before using these new criteria in prospective screenings of predisposed families or in clinical trials. HYPOTHESIS: Radial and longitudinal right and left myocardial motion, assessed by TDI and St variables, is altered in dogs with DCM. ANIMALS: Case records for 26 dogs; 14 with DCM and 12 healthy controls of comparable age and weight were reviewed. METHODS: A retrospective analysis was conducted of conventional echocardiography, 2-dimensional color TDI, and St imaging data. RESULTS: The DCM group was characterized by decreases in radial and longitudinal systolic velocity gradients of the left ventricular free wall (LVFW), radial and longitudinal absolute values of peak systolic St of the LVFW, and longitudinal systolic right ventricular (RV) velocities (all P < .001 versus control) associated with longitudinal postsystolic contraction waves in 7/14 dogs. Early diastolic LVFW velocities also were decreased for longitudinal (P < .01) and radial (P < .05) motions. All radial LVFW, longitudinal basal LVFW, and RV systolic velocities were negatively correlated with heart rate (P < .01). CONCLUSIONS AND CLINICAL IMPORTANCE: LV contractility along both the short and long axes is impaired in dogs with spontaneous DCM, as is systolic RV and diastolic LVFW function. These myocardial alterations are associated with an inverse force-frequency relationship. Studies now are needed to determine the comparative sensitivity of TDI and St variables for the early detection of canine DCM. 相似文献
25.
Three cases of equine subcutaneous pythiosis with dissemination to the internal organs were investigated. The subcutaneous lesions were observed on the mammary gland, nostrils and limbs of the infected horses. Histopathological analysis of the infected tissues revealed a strong eosinophilic reaction, with macrophages, mast cells and giant cells. Sparsely septated hyphal filaments of 4-6 microm diameter were identified in the center of the eosinophilic areas. Specific fluorescent antibody against Pythium insidiosum confirmed the hyphae in the infected tissues in three examined horses. In one of the three cases, the DNA sequences amplified from the infected subcutaneous tissues and internal organs, revealed that P. insidiosum's 18S SSU rDNA amplicons shared 100% identity with those sequences deposit in GenBank. This is the first report confirming by immunochemical and genetic techniques that P. insidiosum can disseminated from superficial to deep structures. 相似文献
26.
Natalia Sevane Hubert Leveziel Geoffrey R Nute Carlos Sanudo Alessio Valentini John Williams Susana Dunner the GeMQual Consortium 《畜牧与生物技术杂志(英文版)》2014,(2):154-162
Background: Consuming moderate amounts of lean red meat as part of a balanced diet valuably contributes to intakes of essential nutrients, in this study, we merged phenotypic and genotypic information to characterize the variation in lipid profile and sensory parameters and to represent the diversity among 15 cattle populations. Correlations between fat content, organoleptic characteristics and lipid profiles were also investigated. Methods: A sample of 436 largely unrelated purebred bulls belonging to 15 breeds and reared under comparable management conditions was analyzed. Phenotypic data -including fatness score, fat percentage, individual fatty acids (FA) profiles and sensory panel tests- and genotypic information from 11 polymorphisms was used. Results: The correlation coefficients between muscle total lipid measurements and absolute vs. relative amounts of polyunsaturated FA (PUFA) were in opposite directions. Increasing carcass fat leads to an increasing amount of FAs in triglycerides, but at the same time the relative amount of PUFAs is decreasing, which is in concordance with the negative correlation obtained here between the percentage of PUFA and fat measurements, as well as the weaker correlation between total phospholipids and total lipid muscle content compared with neutral lipids. Concerning organoleptic characteristics, a negative correlation between fiavour scores and the percentage of total PUFA, particularly to n-6 fraction, was found. The correlation between juiciness and texture is higher than with flavour scores. The distribution of SNPs plotted by principal components analysis (PCA) mainly reflects their known trait associations, although influenced by their specific breed allele frequencies. Conclusions: The results presented here help to understand the phenotypic and genotypic background underlying variations in FA composition and sensory parameters between breeds. The wide range of traits and breeds studied, along with the genotypic information on polymorphisms previo 相似文献
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28.
Evaluation of the Lime-Cooking and Tortilla Making Properties of Quality Protein Maize Hybrids Grown in Mexico 总被引:1,自引:0,他引:1
Serna-Saldivar SO Amaya Guerra CA Herrera Macias P Melesio Cuellar JL Preciado Ortiz RE Terron Ibarra AD Vazquez Carrillo G 《Plant foods for human nutrition (Dordrecht, Netherlands)》2008,63(3):119-125
Eleven experimental and three commercial white quality protein maize (QPM) hybrids and two regular endosperm controls were planted at Celaya, Guanajuato, Mexico with the aim of comparing grain physical characteristics, protein quality, lime-cooking and tortilla making properties. All genotypes were planted under irrigation using a density of 80,000 plants/ha and fertilized with 250 kg N-60 P-60 K per hectare. When compared with the controls these QPM genotypes had lower test (77.4 vs. 76.5 kg/hL) and 1,000 kernel weights (327 vs. 307 g), softer endosperm texture (2.5 vs. 1.8 where 1 = soft, 2 intermediate and 3 hard endosperm), lower protein (10.0 vs. 8.0%), higher nixtamal water uptake after 30 min lime-cooking (50.0 vs. 53.1% moisture) and lower pericarp removal scores. The lower thousand-kernel weight and softer endosperm texture observed in the QPM genotypes lowered the optimum lime-cooking time as estimated with regression equations. Most QPM genotypes had higher amounts of lysine, tryptophan and albumins/globulins when compared with the controls. QPMs HEC 424973, HEC 774986 and HEC 734286 had the best grain traits for nixtamalization and therefore the best potential for industrial utilization. The commercial use of these QPM hybrids should benefit Mexicans who depend on tortillas as the main staple. 相似文献
29.
A. P. Nicolle V. Chetboul H. Namba F. Crespeau A. Tidholm C. Carlos V. Gouni J. L. Pouchelon 《Veterinary radiology & ultrasound》2005,46(3):230-233
A 6-year-old female cat developed pleural and abdominal effusion. Cardiac ultrasound and 2D color tissue Doppler imaging revealed restrictive cardiomyopathy with severe biatrial dilatation and hypertension. This cardiomyopathy was associated with atrial septal aneurysm and a patent foramen ovale. The atrial septal aneurysm involved the entire atrial septum. Necropsy and histological examination confirmed all these findings. ASA is a rare malformation and, as in this cat, it generally occurs concomitantly with congenital or acquired heart disease and may be explained by greater pressure in one atrium, leading to controlateral protrusion of the atrial septum. 相似文献
30.
Renal handling of calcium and phosphorus in experimental renal hyperparathyroidism in dogs 总被引:3,自引:0,他引:3
García-Rodríguez MB Pérez-García CC Ríos-Granja MA Cano-Rábano MJ Peña-Penabad M Gallego-Morales D García-Partida P Diez-Prieto I 《Veterinary research》2003,34(4):379-387
Twenty-four hour urinary excretion, fractional excretion and the filtered load of calcium and phosphorus were monitored as hyperparathyroidism evolved in a model of progressive canine renal failure. Thirteen beagles of both sexes aged four and a half months were used. Nine of them were subjected to a renal damaging schedule (neomycine, 60 mg/kg/48 h, IM, 32 weeks) in order to induce chronic renal failure leading to secondary hyperparathyroidism (2HPT group). The remaining four were kept as the control group. The experiment was conducted over 32 weeks. Blood and 24 h urine were collected every four weeks. Calcium, phosphorus and creatinine were analyzed. Plasma parathormone and calcitonin were determined at weeks 0, 12, 24 and 32. The level of renal function in the 2HPT animals was reduced to 25% of that of the controls (endogenous creatinine clearance was 0.45 +/- 0.22 mL/min/kg as opposed to 1.81 +/- 0.54 mL/min/kg). Hyperparathyroidism was confirmed by a progressive increase in the levels of the parathyroid hormone. Calcitonin levels were not modified. A tendency to hypocalcaemia was observed, reaching statistically significant levels from the twenty-eighth week of the study, when hyperphosphataemia also became significant. Daily urinary excretion of calcium and phosphorus remained at values considered normal throughout the experiment with no alteration imputable to the impaired renal function. This is explained by the decrease in the filtered load of these elements (in both cases statistically significant from the 24th week on) being associated with an increase in their fractional excretion. Thus, calcium and phosphorus urinary excretion values could be maintained in a normal range up to the end of the experiment, showing that renal calcium handling in dogs with experimentally induced renal failure seems to differ from that observed in human patients. 相似文献