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71.
In mined dune areas, revegetation with manured seedlings of native species is a common practice. Establishment of mycorrhized Tocoyena selloana seedlings in the mined coastal sand dunes of Northeast Brazil was tested. In greenhouse, seedlings were grown in substrates with 0, 5, 10, 15 or 20% cattle manure proportions and inoculated with Acaulospora longula, a mixture of native arbuscular mycorrhizal fungi (AMF) or uninoculated. The seedlings responded positively to the inoculation, but growth was limited in the absence of manure, independently of inoculation, and was higher with fertilizing doses ≥10%. The seedlings transplanted to the field were grown in a substrate with 16.5% manure and inoculated with A. longula or Gigaspora albida. After 13 months, 19 AMF species were identified in the rhizosphere and the inoculated plants were more colonized than those uninoculated. Plants associated to G. albida were taller and those associated to A. longula had a tendency of higher biomass than the uninoculated ones. Even though this tendency was not statistically significant, considering the effect on height and the low cost of inoculation it may be a feasible practice to maximize environment restoration.  相似文献   
72.
Different protocols to evaluate teat skin status under field conditions based on scoring and on the measurement of pH and hydration of teat skin were evaluated. After determination of the teat score for all eligible animals in a commercial dairy herd, 50 of them were chosen, based on their pre-trial average teat score, and separated in two groups. Two different post-dipping products with the same amount of disinfectant, but with a different concentration of emollient were applied. All four teats were assessed with the corneometer and pH probes. A digital picture of each teat skin and teat orifice was taken with a digital camera. Hydration and pH data were analysed by anova with repeated-measurement factors, while teat skin and apex score patterns, were assessed by the means of Mann-Whitney test; between- and within-group changes were assessed by the mean of Mantel-Haenzel chi-square statistic. Data showed that teat skin pH and hydration could be assessed under field conditions and they were influenced by teat conditioning. The approach based on evaluating odds for scores, stratified for sampling and for treatment, was found to be a sensitive and informative way to compare the changes between and within treatment groups.  相似文献   
73.
The morphologically small Babesia species isolated from naturally infected dogs in Europe, Japan, and US are described as Babesia gibsoni despite the fact that molecular techniques show that they should be assigned to two or three separate taxons. The morphologically large Babesia isolated from dogs in Europe, Africa, and US were generally classified as B. canis until it was proposed to distinguish three related, albeit genetically distinct subspecies of this genus, namely B. canis canis, B. canis rossi, and B. canis vogeli. The insight into the molecular taxonomy of canine piroplasms is, however, limited because only partial small subunit ribosomal RNA (ssrRNA) sequence data exist for two species from the B. canis group. In this work, we molecularly characterised natural Babesia infections in 11 dogs from Croatia, France, Italy, and Poland. These infections were diagnosed as caused by B. canis canis and B. canis vogeli based on the analysis of the complete sequence of the ssrRNA genes. Phylogenetic analysis confirmed that the large Babesia species of dogs belong the to the Babesia sensu stricto clade, which includes species characterised by transovarial transmission in the tick vectors and by exclusive development inside the mammalian host erythrocytes. The new data facilitate the reliable molecular diagnosis of the subspecies of B. canis.  相似文献   
74.
Globally, the area of land cultivated with genetically modified (GM) crops has increased a thousand-fold over the last two decades. Although this technology has become important for food production, the regulatory frameworks that underpin these outcomes are based on a list of requirements for a risk assessment that differ from country to country. In recent years, policymakers have had the opportunity to learn from the controversies over transgenics to create effective regulatory milestones for emerging technologies, allowing them to reach their potential for a more sustainable agriculture, ensuring food security. In Brazil, Law No. 11.105 of 24 March 2005 established a framework with four main organizations responsible for risk assessment and management. However, most of new breeding technologies did not exist at that time and were not considered in this law. In 2016, Normative Resolution No. 16 of the National Biosafety Technical Commission (CTNBio) was established to address this gap based on the evaluation of the products obtained through these techniques (termed Innovative Precision Improvement Techniques in the resolution), in a case-by-case consultation system. Briefly, if the product is designated to be a GM, the developer will have to go through the biosafety requirements and will be approved only after CTNBio risk assessment. If the product is designated not to be GM (for the purposes of the legislation), then it can be registered using the existing procedures. Currently, 152 GM products are commercially approved in Brazil. In 2018, CTNBio assessed the first consultation on commercial release of plants generated using the new breeding technologies and has subsequently approved six products. It is expected that many institutions would be able to participate in Brazilian and world markets, developing and introducing new biotechnological solutions and products through a more sustainable approach and without facing public disapproval, a common issue for GM crops.  相似文献   
75.
This study evaluated the use of microalgae (Aurantiochytrium sp.) meal as a substitute for fish oil in the diet of juvenile Pacific white shrimp (Litopenaeus vannamei) reared in a clear‐water system. Dietary treatments at five replacement levels (0%, 25%, 50%, 75%, 100%) were performed in triplicate. After 46 days, only a slight difference in shrimp final weight was observed among treatments (0.61 g). An increase in final weight was observed with replacement of up to 50% fish oil for microalgae meal, while the optimal percentage of replacement estimated was 44.7%. Feed conversion rate (FCR) of animals fed a diet of Aurantiochytrium sp.meal to replace up to 50% fish oil decreased, and the optimal percentage of replacement estimated was 49.3%. The fatty acids profile in shrimp muscle tissue demonstrated an increase in docosahexaenoic acid (DHA) from 10.03% to 14.28% with increased replacement of fish oil by microalgae meal in the diet. Therefore, the partial replacement of fish oil by microalgae meal resulted in improved shrimp growth and FCR, and total replacement of dietary fish oil had no negative effects on these parameters. In addition, inclusion of microalgae meal raises the level of DHA in shrimp muscle.  相似文献   
76.
Changes in prevalence in intramammary infection, by pathogen type, in herds applying a stringent contagious mastitis control programme was studied. Enrollment of 1651 lactating cows and collection of milk samples was made in this ancillary study to a cohort study of the dynamics of mastitis prevalence after adoption of a strict contagious mastitis control programme that targeted the elimination of mastitis caused by Staphylococcus aureus. Nine commercial dairies in Italy were used. Aseptic collection of milk samples from all lactating cows was performed at the time of enrollment, from all cows within 7-14 days of entering the lactating herd after the date of enrollment, and from all lactating cows at 2, 4, 7, 10 and 14 months after the date of enrollment. Prevalence of intramammary infection by pathogen type was determined from culture of milk samples. Application of the strict contagious mastitis programme did not lead to an increased risk of non-contagious mastitis. The risk of coliform, environmental streptococcal and coagulase-negative staphylococcal intramammary infections decreased after adoption of the programme. The data reported herein indicate that the overall risk for any intramammary infections decreases with adoption of a strict contagious mastitis programme, and that such a programme therefore does not necessarily lead to an increase in environmental mastitis.  相似文献   
77.
78.
As concerns heighten over links between biomass production and land grabs in the global south, attention is turning to understanding the role of governance of biofuels systems, whereby decision-making and conduct are not solely determined through government regulations but increasingly shaped by non-state actors, including multi-stakeholder initiatives (MSI). Launched in 2005, Bonsucro is the principal MSI that focuses on sustainability standards for sugar and sugarcane ethanol production. Bonsucro claims that because it is free from government interference and draws on scientific metrics, their standards transcend localized, political–economic contexts. In this paper, we illustrate how the local context shapes the prospects for Bonsucro sustainably certified biofuel production in relation to land and water grabs. To accomplish this, our case focuses on Colombia, which has used a range of national policy mandates to establish itself as one of the larger producers of agrofuels in Latin America. We draw on interviews with stakeholders in the sugar and ethanol industries, paired with an examination of Bonsucro principles on land rights and water use, to illustrate how the sugar industry is framing their participation in Bonsucro, and the effects of the increasing intensification of sugarcane for ethanol production on land and water access for communities. We find that within the context of Colombia, efforts such as Bonsucro provide a veil of legitimacy and authority to a system that is premised on deeply entrenched historical patterns of inequitable land ownership patterns and access to natural resources.  相似文献   
79.
To determine the accuracy of Doppler blood pressure measurement in anaesthetised pigs eight large white pigs (Sus scrofa) were anaesthetised with zolazepam and tiletamine as Zoletil 100 (4 mg/kg) and xylazine (2 mg/kg) by intramuscular injection followed by isoflurane in 100% oxygen. Blood pressure measurements were recorded using a Doppler probe on the radial artery and a catheter in the femoral artery connected to a transducer. The sample mean of the Doppler measurements were compared with the sample mean of the invasive systolic arterial blood pressure while accounting for the heart rate, end-tidal CO2 and temperature. The predicted error of the Doppler was greatest when pigs were hypotensive and normothermic: 11 mmHg (CI: 6–15). Doppler measurements should be interpreted with caution in anaesthetised pigs that are hypotensive and normothermic.  相似文献   
80.
Calorie restriction extends life span in organisms ranging from yeast to mammals. Here, we report that calorie restriction for either 3 or 12 months induced endothelial nitric oxide synthase (eNOS) expression and 3',5'-cyclic guanosine monophosphate formation in various tissues of male mice. This was accompanied by mitochondrial biogenesis, with increased oxygen consumption and adenosine triphosphate production, and an enhanced expression of sirtuin 1. These effects were strongly attenuated in eNOS null-mutant mice. Thus, nitric oxide plays a fundamental role in the processes induced by calorie restriction and may be involved in the extension of life span in mammals.  相似文献   
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