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Production of common bean(Phaseolus vulgaris)is limited by the occurrence of damping off(rhizoctoniosis),which is caused by the fungus Rhizoctonia solani.However,the co-inoculation of plant growth-promoting rhizobacteria(PGPR)involved in biological control along with diatomic nitrogen(N2)-fixing rhizobia can enhance N nutrition and increase production.In this context,finding microorganisms with synergistic effects that perform these two roles is of fundamental importance to ensure adequate yield levels.The aim of this study was to evaluate the effects of co-inoculation of nodule endophytic strains of the genera Bacillus,Paenibacillus,Burkholderia,and Pseudomonas with Rhizobium tropici CIAT 899,an N2-fixing rhizobial strain,on the biocontrol of damping off and growth promotion in common bean plants.Greenhouse experiments were conducted under axenic conditions using the common bean cultivar Pérola.The first experiment evaluated the potential of the 14 rhizobacterial strains,which were inoculated alone or in combination with CIAT 899,for the control of R.solani.The second experiment evaluated the ability of these 14 rhizobacterial strains to promote plant growth with three manners of N supply:co-inoculation with CIAT 899 at low mineral N supply(5.25 mg N mL^-1),low mineral N supply(5.25 mg N mL^-1),and high mineral N supply(52.5 mg N mL^-1).The use of rhizobacteria combined with rhizobia contributed in a synergistic manner to the promotion of growth and the control of damping off in the common bean.Co-inoculation of the strains UFLA 02-281/03-18(Pseudomonas sp.),UFLA 02-286(Bacillus sp.),and UFLA 04-227(Burkholderia fungorum)together with CIAT 899 effectively controlled damping off.For the common bean,mineral N supply can be replaced by the co-inoculation of CIAT 899 with plant growth-promoting strains UFLA 02-281/02-286/02-290/02-293.Nodule endophytes UFLA02-281/02-286 are promising for co-inoculation with CIAT 899 in the common bean,promoting synergy with rhizobial inoculation and protection against disease.  相似文献   
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The present work reports a characterization of mean wet weight and moisture, the lipid class and fatty acid (FA) composition from the total lipids (TL), of both culture and wild eggs of the cuttlefish, Sepia officinalis , throughout the embryonic development. Additionally, reproductive data, such as the number of spawnings, number and mean weight of eggs and duration of spawning period of cultured cuttlefish is provided. Both types of eggs were similar in mean wet weight, moisture content, TL content and lipid composition throughout embryonic development. Females from the cultured group spawned 13 times and laid 8654 eggs in 64 days, with a mean weight of 0.607 ± 0.179 g. A sex ratio of 1.57 (11♀ for 7♂) promoted an individual fecundity of 787 eggs/♀ (the biggest until now on our culture facilities), which might be related to increased bottom areas. The TL increased with day/stage of embryonic development ( P  < 0.05) only in the cultured egg group. However, no differences were found on TL between culture and wild eggs at the same day/stage ( P  > 0.05). Eggs displayed predominant levels of phosphatidylcholine, phosphatidylethanolamine (PE), cholesterol and triacylglycerol at the end of embryonic development. Polar and neutral lipids of both eggs groups remained consistently proportional (∼50% for each lipid fraction) and a significant increase ( P  < 0.05) was observed in phosphatidylserine, PE and free FA throughout the embryonic development. In either egg type and day, 16:0, 18:0, 20:5n-3 and 22:6n-3 accounted for approximately 70 g Kg−1 of all FA and saturated and n-3 totals seemed to have the same proportion in the cuttlefish eggs. The present results suggest that lipids are not used as energetic substrate but as structural components in cuttlefish egg.  相似文献   
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In order to identify the factors influencing adoption of technologies promoted by government to small-scale dairy farmers in the highlands of central Mexico, a field survey was conducted. A total of 115 farmers were grouped through cluster analysis (CA) and divided into three wealth status categories (high, medium and low) using wealth ranking. Chi-square analysis was used to examine the association of wealth status with technology adoption. Four groups of farms were differentiated in terms of farms' dimensions, farmers' education, sources of incomes, wealth status, management of herd, monetary support by government and technological availability. Statistical differences (p < 0.05) were observed in the milk yield per herd per year among groups. Government organizations (GO) participated little in the promotion of the 17 technologies identified, six of which focused on crop or forage production and 11 of which were related to animal husbandry. Relatives and other farmers played an important role in knowledge diffusion and technology adoption. Although wealth status had a significant association (p < 0.05) with adoption, other factors including importance of the technology to farmers, usefulness and productive benefits of innovations together with farmers' knowledge of them, were important. It is concluded that the analysis of the information per group and wealth status was useful to identify suitable crop or forage related and animal husbandry technologies per group and wealth status of farmers. Therefore the characterizations of farmers could provide a useful starting point for the design and delivery of more appropriate and effective extension.  相似文献   
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Cassia occidentalis is a bush from the Leguminosae family, subfamily Caesalpinoideae, and is a toxic plant of veterinary interest due to the occasional contamination of animal rations. This report describes the clinical and histopathological findings of an outbreak of C. occidentalis poisoning in horses. Twenty mares were poisoned after consuming ground corn contaminated with 8% of C. occidentalis seeds. Of the 20 animals affected, 12 died: 8 mares were found dead, 2 died 6 h after the onset of clinical signs compatible with hepatic encephalopathy and the 2 other animals were subjected to euthanasia 12 h after the onset of the clinical signs. The remaining 8 mares presented with mild depression and decreased appetite, but improved with treatment and no clinical sequelae were observed. In 6 animals that underwent a necropsy, an enhanced hepatic lobular pattern was noted and within the large intestine, a large number of seeds were consistently observed. Hepatocellular pericentrolobular necrosis and cerebral oedema were the main histological findings. In one mare, there was mild multifocal semimembranosus rhabdomyocytic necrosis and haemorrhage. Seeds collected from intestinal contents and sifted from the culpable feedstuff were planted. Examination of the leaves, flowers, fruits and seeds of the resultant plants identified C. occidentalis. Horses poisoned by C. occidentalis seeds demonstrate clinical signs associated with hepatoencephalopathy and frequently die suddenly. Lesions primarily involve the liver and secondarily, the central nervous system. Cassia occidentalis poisoning should be considered a differential diagnosis in horses with hepatoencephalopathy and special caution should be taken with horse rations to avoid contamination with seeds of this toxic plant.  相似文献   
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Tropical Animal Health and Production - The use and management of native grassland for dairy production during the rainy season was studied on two small-scale dairy farms in the highlands of...  相似文献   
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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   
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The effects of feeding three natural frozen diets, grass shrimp (Palaemonetes sp.), crayfish (Procambarus clarkii) and fish (Sardina pilchardus) and two semi‐humid artificial diets (based on fish or shrimp powder) to the cuttlefish, Sepia officinalis, were analysed. Growth rate and feeding rate [FR; % body weight (BW) day?1] and food conversions (FC, %) were determined. Cuttlefish fed shrimp grew larger (3.8% BW day?1) and had the highest FC, followed by those fed crayfish, and sardine. The highest FR was obtained for cuttlefish fed crayfish (10.5% BW day?1). Although both artificial diets were accepted, none produced growth. Digestive gland‐to‐body weight ratio (DG/BW ratio) was calculated for animals fed each diet. A positive correlation (r = 0.94) between cuttlefish ingestion FR and DG weight was obtained. Mortality occurred mainly during the last week, and some cannibalism occurred among cuttlefish fed artificial diets. Finally, lipid composition of diets, DG and mantle of each group were analysed. Sardine diet was characterized by high levels of triacylglycerol (TG), whereas the main difference between shrimp and crayfish was the higher n‐3/n‐6 ratio found in shrimp. Changes in the lipid composition of DG were related to diet, but did not correlate with growth data. A strong loss of TG in the DG of artificial diets groups was notable. No differences in mantle lipid composition among the natural diets were found, but artificial diet groups showed higher contents of neutral lipids in their mantle respect to natural diets. According to results obtained, crayfish (P. clarkii) could be used as an alternative prey for rearing S. officinalis compared with shrimp. Artificial diets showed the worst effects in growth and mortality as well as the stronger influence on DG and mantle lipid composition of cuttlefish.  相似文献   
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