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101.
Ulises Macías-Cruz Ricardo Vicente-Pérez Miguel Mellado Abelardo Correa-Calderón Cesar A. Meza-Herrera Leonel Avendaño-Reyes 《Tropical animal health and production》2017,49(7):1393-1400
To evaluate the effects of pre- and post-conception undernutrition (UN) on fetal and placental development at mid-gestation, 28 Katahdin × Pelibuey multiparous ewes were blocked by weight and assigned to the following four dietary treatments (n = 7 each): ewes fed 100% (control) or 60% of their nutritional requirements 30 days before mating (UNPre), 50 days after mating (UNPost) or during both periods (UNB). Four twin-bearing ewes were selected per treatment at day 50 post-conception and then slaughtered at day 75 of gestation to analyze their fetuses. Control fetuses were heavier (P < 0.05) than UNPost and UNB fetuses in 14.6 and 9.4%, respectively. Organ weights as percentage of the fetal weight (except for liver) and morphometric measurements (except for abdominal girth) were similar between control and UN fetuses (UNPre, UNPost, and UNB). Placental mass was heavier (P < 0.05) in control ewes than UNB ewes, but not relative to ewes of other treatments. The number of placentomes per ewe and placental efficiency were unaffected by UN treatments. Compared to control, only UNB ewes exhibited variations (P < 0.05) in the proportion of placentomes, specifically for type A (+13.8%) and B (?12.6%). Placentomes of type A and B had lower weight, length, and width of placentas in UNPost and UNB ewes than placentas of control ewes (P < 0.05). Overall results indicate that fetal and placental development of ewes carrying twins is mainly altered when nutritional restriction occurs simultaneously before conception and during the first third of pregnancy. 相似文献
102.
Carotenoid production by the marine microalgae Nannochloropsis oculata in different low‐cost culture media
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Wladimir Angelino Faé Neto Carlos Rafael Borges Mendes Paulo Cesar Abreu 《Aquaculture Research》2018,49(7):2527-2535
Nannochloropsis oculata (Eustigmatophyceae) is a marine microalga of great biotechnological interest, mainly due to its large production of lipids containing polyunsaturated fatty acids. In addition, this species presents a wide range of commercial interest pigments, such as zeaxanthin, beta‐carotene, and other xanthophylls, with potential for several industrial applications. However, most of the research concerning pigment production by N. oculata has been conducted by employing high‐cost laboratorial growth media, which makes large‐scale pigment production using these microalgae impractical. Considering the high interest and commercial value in microalgae pigments, this study investigates the feasibility of producing pigments by N. oculata using five different low‐cost growth media (fertilizers and aquaculture effluents). Nutrient (ammonia, nitrite and phosphate) concentrations, cell abundance, biomass, and the concentration/composition of pigments were measured. The pigment profile of N. oculata showed chlorophyll‐a as the dominant pigment, along with violaxanthin, vaucheraxanthin, and lower concentrations of antheraxanthin, zeaxanthin and beta‐carotene. Although the highest biomass (516.4 ± 76.71 mg/L) and pigment content (0.98 mg/g) were achieved in the laboratory media (f/2), the low‐cost media (containing ammonium sulfate, calcium superphosphate and urea) revealed a great potential for the production of pigments, specially chlorophyll‐a, violaxanthin and zeaxanthin, due to the high pigment content per unit of biomass. 相似文献
103.
Effects of live feed containing Panagrellus redivivus and water depth on growth of Betta splendens larvae
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Márcia Valéria Silva do Couto Natalino da Costa Sousa Higo Andrade Abe Joel Artur Rodrigues Dias Juliana Oliveira Meneses Peterson Emmanuel Guimarães Paixão Fernanda dos Santos Cunha Fabrício Menezes Ramos Alexandre Nizio Maria Paulo Cesar Falanghe Carneiro Rodrigo Yudi Fujimoto 《Aquaculture Research》2018,49(8):2671-2675
Panagrellus redivivus is a nematode with a high protein content and low‐cost production. It is successfully used in the larviculture of shrimp, however, it has not yet been evaluated as feed for Betta splendens larvae. Thus, the objective of this study was to evaluate P. redivivus as feed for betta larvae maintained at different depths of water. The experiment was based on a completely randomized 3 × 2 factorial design, represented by two feed types and one alternating feeding regime plus two water depths (2.5 and 5.0 cm). The Artemia feed promoted the highest weight gain, followed by the alternating feeding regime. The single use of the nematode as live feed produced the poorest weight gain. The water depth and the feeding method influenced the specific growth rate (SGR). At a depth of 2.5 cm, the alternating feeding promoted similar SGR compared to fish fed with Artemia only. Furthermore, at the greater water depth an improvement in SGR was observed in fish fed Artemia only, but the similarity to alternating feeding regime remains. Thus, the inclusion of nematode is an appropriate and lower cost feed strategy for the betta larviculture independent of water depths. 相似文献
104.
105.
Pablo Gonzalez-de-Santos Angela Ribeiro Cesar Fernandez-Quintanilla Francisca Lopez-Granados Michael Brandstoetter Slobodanka Tomic Stefania Pedrazzi Andrea Peruzzi Gonzalo Pajares George Kaplanis Manuel Perez-Ruiz Constantino Valero Jaime del Cerro Marco Vieri Gilles Rabatel Benoit Debilde 《Precision Agriculture》2017,18(4):574-614
Feeding the growing global population requires an annual increase in food production. This requirement suggests an increase in the use of pesticides, which represents an unsustainable chemical load for the environment. To reduce pesticide input and preserve the environment while maintaining the necessary level of food production, the efficiency of relevant processes must be drastically improved. Within this context, this research strived to design, develop, test and assess a new generation of automatic and robotic systems for effective weed and pest control aimed at diminishing the use of agricultural chemical inputs, increasing crop quality and improving the health and safety of production operators. To achieve this overall objective, a fleet of heterogeneous ground and aerial robots was developed and equipped with innovative sensors, enhanced end-effectors and improved decision control algorithms to cover a large variety of agricultural situations. This article describes the scientific and technical objectives, challenges and outcomes achieved in three common crops. 相似文献
106.
Roberto G. Chiquito-Contreras Bernardo Murillo-Amador Cesar J. Chiquito-Contreras Jhovana C. Márquez-Martínez Miguel V. Córdoba-Matson 《Journal of plant nutrition》2017,40(18):2595-2601
The habanero pepper is widely used in a variety of commercial food products. The increase in the cultivation area of the habanero pepper has increased the use of agricultural inputs, mainly inorganic fertilizers, which have high economic costs and cause negative effects to the soil and water. In recent years, the use of beneficial soil microorganisms has been studied as an alternative to inorganic fertilizers. In the present study, the effect of three strains of Pseudomonas putida on the growth and productivity of King Pakal hybrid habanero pepper with limited inorganic fertilizer in a greenhouse. It was found that a reduction of inorganic fertilizer application of 25% with P. putida rhizobacteria strains increased or maintained growth and productivity of King Pakal hybrid habanero pepper. Before these rhizobacteria can be used in the field, results will first need to be confirmed under more natural conditions. 相似文献
107.
Nicolas Rispail Péter Kaló György B. Kiss T.H. Noel Ellis Karine Gallardo Richard D. Thompson Elena Prats Estibaliz Larrainzar Ruben Ladrera Esther M. González Cesar Arrese-Igor Brett J. Ferguson Peter M. Gresshoff Diego Rubiales 《Field Crops Research》2010
Faba bean is an excellent candidate crop to provide nitrogen input into temperate agricultural systems. However, its growth is hampered by several factors including environmental stresses and the presence of anti-nutritional factors. To solve these limitations, breeding programs have been initiated that were successful for monogenic traits but not so for multigenic traits. The large genome size of faba bean has slowed down breeding processes. Several other legumes have emerged as model legumes including Medicago truncatula, Lotus japonicus, Glycine max and Pisum sativum. The establishment of these models has already boosted our understanding of important processes such as the nitrogen-fixing symbiotic interaction. The high level of synteny and collinearity existing between legumes makes possible the transfer of key knowledge from model legumes to faba bean. Here we review the most recent knowledge gained from model legumes on grain quality, resistance to biotic and abiotic stresses, nitrogen-fixing symbiosis and how this knowledge can be employed for faba bean breeding. 相似文献
108.
Janice A. Cruz Cardona Heather L. Wamsley Lisa L. Farina Matti Kiupel 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2010,39(3):371-376
Abstract: A 14‐year‐old female spayed Golden Retriever was presented to the University of Florida's Veterinary Medical Center with history of lymphoplasmacytic gastroenteritis, intermittent vomiting, watery diarrhea, and weight loss for over a year. CBC, biochemical profile, and urinalysis were within reference intervals. Abdominal ultrasonographic examination revealed mesenteric and jejunal lymphadenopathy and hyperechoic hepatic nodules. Cytologic examination of the enlarged lymph nodes revealed loosely cohesive cells with moderate nuclear pleomorphism and rare punctate eosinophilic cytoplasmic granules. The cytologic interpretation was metastatic neuroendocrine neoplasia. On surgical exploration, a mass was detected in the right lobe of the pancreas. Histologic evaluation determined the mass to be an islet cell tumor. Approximately 98% of cells were positive by immunolabeling for pancreatic polypeptide (PP), and only rare cells were positive for insulin or somatostatin. All cells were negative for glucagon, gastrin, vasoactive intestinal polypeptide, protein gene product 9.5, synaptophysin, and chromogranins A and B. Pancreatic tumors that primarily produce PP are rare in dogs, and this is the first report of both the cytologic and histologic features of an islet cell tumor predominantly secreting PP. Clinical signs for these tumors are typically absent or nonspecific; signs may include watery diarrhea, as noted in this dog, although the diarrhea may have resulted from lymphoplasmacytic gastroenteritis. Additional case studies are needed to further characterize the cytomorphologic features and clinical presentation of PP‐secreting islet cell tumor, or polypeptidoma, in dogs. 相似文献
109.
W. M. S. Bispo L. Araújo M. B. Bermúdez‐Cardona I. S. Cacique F. M. DaMatta F. A. Rodrigues 《Plant pathology》2015,64(3):627-637
Mango wilt is one of the most important diseases affecting mango production, yet the physiological mechanisms underlying host responses to this fungal infection are poorly known. The disease attenuation displayed by some mango cultivars might be related to higher antioxidant capacities in leaves. To test this hypothesis, the activities of a range of enzymes (e.g. superoxide dismutase and catalase) and metabolites (e.g. ascorbate and glutathione) involved in the antioxidant system, as well as some markers for oxidative stress (e.g. hydrogen peroxide and malondialdehyde equivalents), were evaluated for 30 days after the inoculation of mango plants with Ceratocystis fimbriata. Tommy Atkins plants displayed higher values for the upward, downward and radial fungal colonization of the stem tissues than Ubá plants. In contrast to the working hypothesis, Tommy Atkins plants exhibited more prominent increases in enzyme activities and metabolite concentrations related to oxidative stress responses. These increases were minimal, if any, in Ubá plants. These results suggest that Tommy Atkins plants are less effective at restraining fungal spread through vascular tissues and thus trigger leaf antioxidant defences to cope with the developing stress. 相似文献
110.
Bacterial community of pond's water,sediment and in the guts of tilapia (Oreochromis niloticus) juveniles characterized by fluorescent in situ hybridization technique
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Alessandro Del'Duca Dionéia Evangelista Cesar Paulo César Abreu 《Aquaculture Research》2015,46(3):707-715
Information about bacterial community structure and functioning in fish farming ponds remains scarce, mainly due to methodological difficulties in counting and identifying uncultured bacteria. The main objective of this study was to evaluate the degree of similarity between the bacterial community of the digestive tract of tilapia (Oreochromis niloticus) juveniles and that of the test pond's water and sediment, using the Fluorescent In Situ Hybridization (FISH) technique. Samples of water, sediment and gut content of 30 tilapia juveniles from a single nursery ground were collected in January 2010. Potentially probiotic and pathogenic bacteria of the species Bacillus, Lactobacillus brevis, Lactobacillus collinoides, Lactobacillus coryniformis, Lactobacillus farciminis, Vibrio and Pseudomonas fluorescens were found in different samples using specific fluorescent probes. The similarity between bacterial community environments and gastrointestinal tracts was determined using the Morisita‐Horn index. The fish guts presented higher abundances of Pseudomonas fluorescens, Bacillus, Lactobacillus brevis and Lactobacillus collinoides. The bacterial community composition of tilapia gastrointestinal tract was more similar to the water than the sediment of the pond. The results of this study showed that the FISH technique can be easily used for monitoring of probiotics and pathogen detection in aquaculture systems. 相似文献