日粮中蛋白质和纤维水平对仔猪生产性能和健康状况的影响

为了研究日粮的蛋白质和纤维水平对仔猪生产性能和健康状况的互作,特选择96头35日龄的仔猪（体重为9.11±0.60kg）,分32个栏饲养,每栏3头,分成4个日粮处理组,饲喂期21d。在设定的2×2因子处理中,4种日粮以大米、奶制品和大豆粕为基础配制,日粮蛋白质设两个水平（15.4%与19.4%,风干基）,纤维也设两个水平[低水平纤维（LF）为含5.3%中性洗涤纤维,高水平纤维（HF）为含7.15%中性洗涤纤维,风干基]。高水平纤维日粮组在基础日粮中添加了40g/kg的小麦麸和20g/kg的甜菜浆。每周测定动物生产性能,试验第1天和最后一天收集粪样进行微生物学分析,并且按1（液态）到4（硬实）的评分体系对粪便进行评分。在试验最后1d,每栏选1头猪采集血液,分析急性期反应蛋白（acute-phase protein）和主要急性期反应蛋白（major acute-phase prot）（即Pig-MAP）的含量,随后进行屠宰,对消化道（包括内容物）进行称重,并进行结肠组织学分析。饲喂高水平纤维日粮的仔猪具有较大的平均日增重（390g与457g,P≤0.001）和大肠重量（以占体重比例衡量为4.4%与5.4%,P≤0.05）。这与较高的短链脂肪酸浓度（尤其是乙酸和丁酸）、较少的大肠杆菌数量（每克粪便含7.77与6.86logcfu,P≤0.05）和较高乳酸杆菌与肠道细菌比（0.76与1.37,P≤0.05）是相符的。虽然日粮蛋白质水平没有改变猪的生产性能,但是20%的蛋白质水平提高（P≤0.05）了小肠（6.5与7.7）和大肠（3.8与4.3）的相对重量（占体重的百分比）。在大肠内,含20%蛋白质的日粮使仔猪杯状细胞数量增加（4.6/100与5.4/100μm;P≤0.05）,并使肠上皮内淋巴细胞数量减少（1.8/100与1.3/100μm;P≤0.05）。在健康状况方面,提高日粮纤维水平所产生的效果与日粮中的蛋白质含量有关。在含16%蛋白质的日粮中增加纤维水平可降低粪便评分值、增加抗生素治疗次数,然而在?     

Congenital oligodontia of the deciduous teeth and anodontia of the permanent teeth in a cat

This report describes a rare case of congenital oligodontia of the deciduous teeth and anodontia of the permanent teeth in a cat. According to cat's veterinarian, the patient had only two deciduous upper canines and no permanent teeth had ever erupted. Post-mortem evaluation showed a complete absence of teeth in the oral cavity and inflammatory lesions were not found on the gums. Histopathological analysis of serial sections of maxilla and mandible revealed absence of odontogenic epithelium, inflammatory cells and odontoclastic resorptive lesions. Diagnosis was confirmed after both the establishment that there were no remaining dental structures and the exclusion of other relevant diseases that lead to tooth loss, such as periodontal disease, renal fibrous osteodystrophy, odontoclastic resorptive lesions, ectodermal dysplasia and trauma.     

Silica content in soil solution and its relation with phytolith weathering and silica biogeochemical cycle in Typical Argiudolls of the Pampean Plain,Argentina—a preliminary study

Purpose  

Little is known on the silica biogeochemical cycle in terrestrial environments. The aim of this work is to assess phytolith’s role on the biogeochemical cycle of Si in Typical Argiudolls under different vegetation of the Pampean Plain, Argentina.     

玉米花粉寿命及有效控制花粉飘逸的隔离距离研究

花粉是玉米基因飘逸的重要载体。研究了花粉活力的持续时间和有效控制基因飘逸的隔离距离。在花药刚开裂时采集花粉,置于薄膜层上,放在室外自然条件下保存,每隔一定时间对采集的花粉进行目测和授粉．通过对花粉的目测评判和计算结实率评估花粉活力。试验花粉源区域4000m^2,在其周围不同距离的地方种植若干玉米小区,每个小区面积为12．8m^2,以测定隔离距离的有效性。作为花粉源的玉米材料包含可用于测定花粉飘逸的叶色标记或种子标记。由于大气压不同,花粉可在花药开裂后1～2小时内保持活力。假定花粉以当地下午平均最大风速直线传播,并可在2小时内保持花粉活力,且忽略花粉沉降率因素,理论上讲,具有活力的花粉可以传播的最大距离为32km。试验结果是在离花粉源100m发生了一定数量的异花授粉,离花粉源200m处有个别异花授粉发生。离花粉源300m处没有异花授粉发生。试验结果与玉米花粉不耐干燥并具高沉降速率的结论一致。试验结果表明距离隔离是控制玉米因授粉而发生基因飘逸的有效方法。     

Glycosides from Marine Sponges (Porifera, Demospongiae): Structures, Taxonomical Distribution, Biological Activities and Biological Roles

Literature data about glycosides from sponges (Porifera, Demospongiae) are reviewed. Structural diversity, biological activities, taxonomic distribution and biological functions of these natural products are discussed.     

Factors that modify early and late reproductive phases in oilseed rape (Brassica napus L.): Its impact on seed yield and oil content

Oilseed rape yield potential could be improved lengthening the duration of the late reproductive phase by increasing the number of grains per unit area. Photoperiod sensitivity could be used as a tool to manipulate the reproductive phase and thereby the number of grains. The aim of this study was to assess (i) the effects of different combinations of photoperiod on the duration of different phases and (ii) analyze how the changes in that duration affect yield (and its components) as well as oil seed content in oilseed rape. Field experiments were conducted in a factorial combination of three cultivars and three photoperiod regimes: natural photoperiod (NP) which represents the control and extended photoperiod of 6 h over NP (NP + 6) during emergence (E)-flower buds visible (FBV) and FBV-maturity (M) arranged in a randomized complete block design with three replicates, during two years representing three environments. Results showed that oilseed rape evidenced photoperiod responses during vegetative and early reproductive phases. Due to the lack of correlation between the duration of the vegetative and reproductive phases, it is possible to speculate the vegetative period may be altered independently of the modification of the rest of the phases. The positive relationship between grain number per m² and the duration of the late reproductive phase suggests that yield could be increased by lengthening the duration of that phase. Thus, regardless of the effect on the previous phase, the photoperiod sensitivity found in the early reproductive phase opens the possibility to manipulate the relative durations of vegetative and reproductive phases. Therefore, the length of the reproductive phase will be increased at the expense of a reduction in the duration of the vegetative phase, but without changing the whole duration of the crop cycle. This strategy could increase yield in oilseed rape in the future. Variations in yield were mostly explained by changes in the grain number per unit area without significant correlation with grain weight. However, a negative relationship between grain weight and grain number was found, showing a slight counterbalance in yield, by decreasing the grain weight. Since oil concentration appeared to be a more conservative attribute, increases in crop yield through a higher grain number per unit area would be a suitable strategy for improving oil yield as no reductions in oil concentration can be expected.     

Biomarkers of oxidative stress and antioxidant defences as indicators of different disinfectants exposure in the heart of rainbow trout (Oncorhynchus Mykiss Walbaum)

The aim of this study was to evaluate the impacts of different disinfectants' treatment using in aquaculture on the oxidative stress biomarkers such as thiobarbituric acid reactive substrates (TBARS) and carbonyl derivatives of protein oxidative modification, as well as antioxidant defences [superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR) and glutathione peroxidase (GPx) activity] and total antioxidant capacity (TAC) in the heart tissue of rainbow trout (Oncorhynchus mykiss). In the disinfectants exposure, fish were treated to chloramine‐T (final concentration 10 g m^?3), chloride dioxide (5 g m^?3), formalin (200 mL m^?3) and CIP disinfectant based on peracetic acid and hydrogen peroxide (16 mL m^?3) for 20 min and repeated three times every 3 days. Both chlorine dioxide and formalin treatment was indicated by a significant increase in the level of heart TBARS levels and carbonyl derivatives content and decreased SOD activity. Tissue oxidative stress biomarkers were unchanged upon chloramine‐T or CIP disinfectant exposure. Increased oxidative stress could modify antioxidant defences, principally causing increased CAT activity in the heart tissue of formalin‐ or ClO₂^?‐exposed fish. The correlation between oxidative stress biomarkers and GPx activity indicates that enzymes related to glutathione metabolism were responsible to formalin or ClO₂^?‐induced oxidative stress. Hence, TBARS, carbonyl derivatives and antioxidant defences could be used as biomarkers in evaluating the toxicity of formalin and chlorine dioxide using as disinfectants to trout.     

Tissue-specific responses of oxidative stress biomarkers and antioxidant defenses in rainbow trout Oncorhynchus mykiss during a vaccination against furunculosis

The present study was conducted to evaluate the effects of vaccination against furunculosis on responses of oxidative stress and antioxidant defenses in rainbow trout Oncorhynchus mykiss muscle, gills, liver, and brain tissues. The oxidative stress markers (malondialdehyde and carbonyl derivatives of protein oxidative destruction levels), antioxidant defenses (superoxide dismutase, catalase, glutathione reductase, and glutathione peroxidase), and total antioxidant capacity in different tissues of rainbow trout were measured. Our data showed that exposure of trout to vaccine against furunculosis produced changes (either increase or decrease) in oxidative stress and antioxidant enzymes responses, and these responses showed marked organ differences, associated with tissue patterns. Our study demonstrated that vaccinated trout showed alteration in antioxidant defenses and oxidative stress responses, with higher severity in the liver, compared with other tissues. Our data also suggest that vaccination against furunculosis induced lipid peroxidation in gill and liver tissues. However, muscle and brain tissue are capable of restoring its pro- and antioxidant balance after vaccination.     

Isoflurane minimum alveolar concentration sparing effects of fentanyl in the dog

Objective

To characterize the isoflurane-sparing effects of a high and a low dose of fentanyl in dogs, and its effects on mean arterial pressure (MAP) and heart rate (HR).