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31.
Determination of the genetic compatibility between self-incompatible cultivars is crucial in agriculture. The Rosaceae family carries the S-RNase-mediated gametophytic self-incompatibility (GSI) system. Each haplotype is conferred by an S-locus. The S-locus contains two highly polymorphic genes, S-RNase and SFB, which are characteristic of each haplotype and therefore these genes are ideal markers for molecular S-genotyping. In this study 43 Japanese plum cultivars grown in Israel were S-genotyped based on their S-RNase gene sequences. Four alleles, Sb, Sc, Se and Sh are widespread and together are responsible for 87% of the S-haplotypes therefore many of the cultivar combinations are semi-compatible. In Israel semi-compatibility was shown to correlate with low yield. However, two cultivars, ‘Wickson’ SfSk and ‘Shiro’ SfSg carry rare S-haplotypes and, therefore, are fully compatible with most of the analyzed cultivars.  相似文献   
32.
This study aimed to evaluate the effect of virginiamycin on the metabolism and performance of growing Nellore bulls under low and high gain rates on pasture. In experiment 1, 80 Nellore bulls (age = 12 ± 2 months, body weight = 258 ± 15 kg) were assigned to 16 paddocks in a 2 × 2 randomized block factorial arrangement. In experiment 2, 12 cannulated Nellore bulls were assigned to three 4 × 4 balanced Latin squares. The factors were: (1) mineral salt without or with virginiamycin, and (2) low or high gain rate. No interaction was noted between factors (> .10). Animals fed virginiamycin had greater average daily gain (14%, < .01), body weight (11 kg, = .05), plasma nonesterified fatty acid (20%, < .01), serum calcium concentration (2.62%, = .04), and total protozoa (= .03) and had the same bacterial proportion (> .27). Animals with a low gain rate had greater serum urea concentration (19.6%, < .01) and ruminal ammonia nitrogen (62%, < .01). Thus, virginiamycin increases the performance and changes the metabolism of growing Nellore bulls under low and high gain rates on pasture.  相似文献   
33.
This report describes an alternative surgical technique for performing scrotal ablation and orchiectomy in the adult male sugar glider (Petaurus breviceps) using electrosurgery. Eight animals from a local small mammal shelter group that presented for routine surgical castration for population control measures were included in this study. Mean surgical time was 4.37 ± 2.13 seconds. Mean anesthesia time was 12.32 ± 5.63 minutes. Mean recovery time was 8.37 ± 3.68 minutes. Mean total procedure time was 22.24 ± 5.69 minutes. No perioperative complications were reported. All animals appeared to have sufficient pain management with an analgesia and anti-inflammatory protocol using butorphanol and meloxicam. No over grooming and or self-injurious behaviors were reported by the local shelter during both the 24-hour and 14-day recheck examinations. Electrosurgery scrotal ablation and orchiectomy therefore offers an alternate route for the practicing veterinarian to perform safe and efficient castrations in male sugar gliders. Histologically, in the epididymis, 3 of the 8 sugar gliders had evidence of a well-defined region in the head, between the efferent ducts and the remaining epididymis. The lining cells differed morphologically from those constituting the remaining epithelial lining. The presence of eosinophilic vacuoles in the cytoplasm of the cells in this region suggests a secretory activity.  相似文献   
34.
Front-face fluorescence spectroscopy, directly applied on honey samples, was used for the authentication of 11 unifloral and polyfloral honey types (n = 371 samples) previously classified using traditional methods such as chemical, pollen, and sensory analysis. Excitation spectra (220-400 nm) were recorded with the emission measured at 420 nm. In addition, emission spectra were recorded between 290 and 500 nm (excitation at 270 nm) as well as between 330 and 550 nm (excitation at 310 nm). A total of four different spectral data sets were considered for data analysis. Chemometric evaluation of the spectra included principal component analysis and linear discriminant analysis; the error rates of the discriminant models were calculated by using Bayes' theorem. They ranged from <0.1% (polyfloral and chestnut honeys) to 9.9% (fir honeydew honey) by using single spectral data sets and from <0.1% (metcalfa honeydew, polyfloral, and chestnut honeys) to 7.5% (lime honey) by combining two data sets. This study indicates that front-face fluorescence spectroscopy is a promising technique for the authentication of the botanical origin of honey and may also be useful for the determination of the geographical origin within the same unifloral honey type.  相似文献   
35.
Sporotrichosis is a mycosis caused by Sporothrix schenckii. The most affected animal is the cat; it has played an important role in the zoonotic transmission of this disease, especially in Rio de Janeiro, Brazil, since 1998. In order to evaluate the treatment of feline sporotrichosis with potassium iodide, an observational cohort was conducted in 48 cats with sporotrichosis at Instituto de Pesquisa Clínica Evandro Chagas, Fiocruz. All cats received potassium iodide capsules, 2.5 mg/kg to 20 mg/kg q24h. The cure rate was 47.9%, treatment failure was 37.5%, treatment abandonment was 10.4% and death was 4.2%. Clinical adverse effects were observed in 52.1% of the cases. Thirteen cats had a mild increase in hepatic transaminase levels during the treatment, six of them presented clinical signs suggestive of hepatotoxicity. Compared to previous studies with itraconazole and iodide in saturated solution, potassium iodide capsules are an alternative for feline sporotrichosis treatment.  相似文献   
36.
Breeding value evaluation for UK Limousin beef cattle data was carried out by multiple-trait linear–threshold animal model with variance components assumed to be known. Polychotomous calving ease with five categories was analysed with two continuous traits: birth weight and gestation length. Field data consisted of 220,799 animals with observations with every possible combination of traits, and 270,035 animals in the pedigree. The threshold model was solved either with Newton Raphson or Expectation Maximisation algorithm, and solutions were compared to evaluation by a linear model with original and normalised scores. There were insignificant differences in solutions between the two algorithms for threshold model analyses. Furthermore, solutions of the continuous traits were similar by the threshold and linear models. For the categorical trait, correlations for random effects from the threshold and linear models were high. In case of normalised scores (original scores case in brackets) correlations with solutions from the threshold and linear model were 0.97 (0.94) and 0.97 (0.93) for direct and maternal genetic effects and 0.95 (0.89) for permanent maternal effects. Even so, at least one third of the top 1% ranking of bulls differed between the linear and the threshold models. Predictive abilities as correlations between estimated breeding values and pedigree indices were almost equal between the linear and threshold models for both continuous and categorical traits. In conclusion, despite the higher computational demand, the linear–threshold animal model can be seen worthwhile in the genetic evaluation of the national UK beef cattle data set.  相似文献   
37.
The advantages of using cryopreserved semen in equine reproduction are well known. During cryopreservation, spermatozoa undergo many changes that lead to a decrease in fertility. There is no agreement on the ideal sperm dose and concentration to maximize fertility rates. Thus, the objectives of this experiment were to evaluate sperm motion by computer-assisted analysis (CASA), sperm membrane integrity and function with fluorescence probes of cryopreserved sperm at three concentrations: 100 (C100), 200 (C200) and 400 × 106 sperm/mL (C400), and two straw volumes (0.50 and 0.25 mL). There was no interaction between sperm concentration and storage volume (P > .05). Sperm motion characteristics were influenced by concentration (C100 > C200 > C400; P < .05). Curvilinear velocity (VCL) in 0.25-mL straws had higher average values (P < .05). Membrane integrity and function were not changed by straw volume (P > .05). However, sperm concentration changed the percentage of cells with intact plasma membrane (C100 > C200 > C400; P < .05) and the percentage of cells with high mitochondrial membrane potential (C100 = C200; P > .05 and C400 < C100 and C200; P < .05). According to this experiment, the best freezing method was that involving 100 × 106 sperm/mL, regardless of straw volume.  相似文献   
38.
Water, Air, & Soil Pollution - Laboratory snow melting experiments were conducted with actual late-winter snow samples, collected just before the final snowmelt, in two similar northern Swedish...  相似文献   
39.
Fisheries management requires knowledge on the population dynamics of exploited stocks. To that end, the present study used a mark–recapture approach to characterise the population demographics of roundjaw bonefish Albula glossodonta (Forsskål) and their interaction with a data‐limited fishery on Anaa Atoll in the Tuamotu Archipelago of French Polynesia. Over the course of the study, 2,509 bonefish were tagged and 12.3% were recaptured. The L of bonefish was estimated at 71 cm fork length (FL) with a K of 0.17, based on changes in FL between capture events. Artisanal fish traps located in the migratory corridors of the atoll accounted for 94% of recaptures and these movements occurred during the waning moon. Fishing mortality increased as bonefish reach sexual maturity, recruiting to the trap fishery at age 4 with the onset of spawning behaviour. Bonefish abundance between ages 3 and 5 was estimated to be 29,079 individuals. This case study demonstrated the utility of mark–recapture in filling knowledge gaps that impede the management of data‐limited fisheries. Ultimately, these results supported the creation of an Educational Managed Marine Area and the resurgence of rahui (seasonal closure) to manage this fishery.  相似文献   
40.
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