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101.
Feed handling of lactating crossbred cows maintained in a semi‐arid region during the hot season: physiological parameters,ingestive behavior and performance
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Rafael de Paula Xavier de Andrade Marcelo de Andrade Ferreira Marcílio de Azevedo Emmanuelle Cordeiro da Silva Stela Antas Urbano Maria Gabriela da Conceição Janaina de Lima Silva 《Animal Science Journal》2017,88(1):166-172
The effects of time of feed delivery (14.00 hours; 14.00 and 20.00 hours; 16.00 and 18.00 hours) on the physiological parameters, ingestive behavior, nutrient intake and production of lactating cows maintained in a semi‐arid region during the hot season were evaluated. Regardless of treatment, all animals received the first feeding supply at 06.00 hours. Eight cows with an average body weight of 600 kg, average milk yield of 20 kg/day and 80 days in milk were utilized. The rectal temperature, respiratory rate and sweating rate were not affected (P > 0.05), with average values of 38.5°C, 53.8 movements/min and 104 g/m2/h respectively. There was no effect (P > 0.05) on the eating time (314 min/day), ruminating time (564 min/day), drinking time (61 min/day) and idle time (502 min/day). Similarly, the intake of nutrients and performance of lactating cows were not affected (P > 0.05), with average dry matter intake of 19.8 kg/day, 4% fat‐corrected milk of 20.6 kg/day and milk fat concentration of 4.03 g/100 g. Since the behavior and performance have not altered, any times of feed delivery evaluated could be used to crossbred Holstein × Zebu cows maintained on a feedlot in semi‐arid regions during the hot season. 相似文献
102.
In spite of widespread application of flutamide in the endocrine therapies of young and adult patients, the side effects of this antiandrogen on spermatogenesis and germ‐cell morphology remain unclear. This study evaluates the short‐term androgen blockage effect induced by the administration of flutamide to the testes of pubertal (30‐day old) and adult (65‐ and 135‐day old) guinea pigs, with an emphasis on ultrastructural alterations of main cell types. The testes removed after 10 days of treatment with either a non‐steroidal antiandrogen, flutamide (10 mg/kg of body weight) or a pharmacological vehicle alone were processed for histological, quantitative and ultrastructural analysis. In pubertal animals, flutamide androgenic blockage induces spermatogonial differentiation and accelerates testes maturation, causing degeneration and detachment of primary spermatocytes and round spermatids, which are subsequently found in great quantities in the epididymis caput. In post‐pubertal and adult guinea pigs, in addition to causing germ‐cell degeneration, especially in primary spermatocytes, and leading to the premature detachment of spherical spermatids, the antiandrogen treatment increased the relative volume of Leydig cells. In addition, ultrastructural evaluation indicated that irrespective of age antiandrogen treatment causes an increase in frequency of organelles involved with steroid hormone synthesis in the Leydig cells and a dramatic accumulation of myelin figures in their cytoplasm and, to a larger degree, in Sertoli cells. In conclusion, the transient exposition of the guinea pigs to flutamide, at all postnatal ages causes some degenerative lesions including severe premature detachment of spermatids and accumulation of myelin bodies in Leydig and Sertoli cells, compromising, at least temporarily, the spermatogenesis. 相似文献
103.
A Casao S Vega I Palacín R Pérez‐Pe A Laviña FJ Quintín E Sevilla JA Abecia JA Cebrián‐Pérez F Forcada T Muiño‐Blanco 《Reproduction in domestic animals》2010,45(3):425-432
The effect of melatonin implants administered during non‐breeding season in Rasa Aragonesa rams on sperm motility parameters and other reproductive traits was assessed. In a first experiment, two Rasa Aragonesa rams were implanted (with melatonin group M), remaining other two males as control group (C). Semen of each group was collected from 1 May to 23 June, twice or three times a week, and motility parameters were assessed using a computer‐assisted sperm analysis system. Melatonin increased the percentage of progressive motile spermatozoa, particularly during 46–75 days after melatonin implantation (p < 0.01). In experiment 2, M and C in vitro fertilization ability had been determined by zona‐pellucida binding assays, using spermatozoa from experiment 1, obtained 60–70 days after melatonin was implanted. A significantly higher number of spermatozoa attached per oocyte was observed in frozen‐thawed immature ovine oocytes incubated with sperm from M animals than in those incubated with sperm from the C group (p < 0.01). Finally, a field assay (experiment 3) was performed. In this case, five Rasa Aragonesa rams were implanted with melatonin and three remained as control group. Sperm doses from those animals were used for artificial insemination of 2608 Rasa Aragonesa ewes from 39 different farms at non‐breeding season. Fertility, litter size and fecundity were studied. Semen from melatonin implanted rams seemed to increase both fertility and fecundity in ewes inseminated with spermatozoa obtained 46–60 days after implantation (p < 0.1). Thus, melatonin treatment in rams during non‐breeding season modifies sperm motility parameters and seems to improve the fertilization parameters obtained. 相似文献
104.
Laura P. Rodríguez Virginia González Aníbal Martínez Beatriz Paz Jorge Lago Victoria Cordeiro Lucía Blanco Juan Manuel Vieites Ana G. Cabado 《Marine drugs》2015,13(4):1666-1687
Lipophilic marine toxins pose a serious threat for consumers and an enormous economic problem for shellfish producers. Synergistic interaction among toxins may play an important role in the toxicity of shellfish and consequently in human intoxications. In order to study the toxic profile of molluscs, sampled during toxic episodes occurring in different locations in Galicia in 2014, shellfish were analyzed by liquid chromatography tandem mass spectrometry (LC–MS/MS), the official method for the detection of lipophilic toxins. The performance of this procedure was demonstrated to be fit for purpose and was validated in house following European guidelines. The vast majority of toxins present in shellfish belonged to the okadaic acid (OA) group and some samples from a particular area contained yessotoxin (YTX). Since these toxins occur very often with other lipophilic toxins, we evaluated the potential interactions among them. A human neuroblastoma cell line was used to study the possible synergies of OA with other lipophilic toxins. Results show that combination of OA with dinophysistoxin 2 (DTX2) or YTX enhances the toxicity triggered by OA, decreasing cell viability and cell proliferation, depending on the toxin concentration and incubation time. The effects of other lipophilic toxins as 13-desmethyl Spirolide C were also evaluated in vitro. 相似文献
105.
Donald A Ukeh Michael A Birkett Toby JA Bruce Eunice J Allan John A Pickett A Jennifer Mordue 《Pest management science》2010,66(1):44-50
BACKGROUND: Four‐arm olfactometer bioassays were conducted to assess the behavioural responses of the adult maize weevil, Sitophilus zeamais (Motschulsky) (Coleoptera: Curculionidae), to harvested seeds of host plants, i.e. white maize, yellow maize (Zea mays L.) and winter wheat (Triticum aestivum L.) (Poaceae), and non‐host plant materials, i.e. alligator pepper, Aframomum melegueta (Rosk) K. Schum (Zingiberaceae), rhizomes of ginger, Zingiber officinale (Roscoe) (Zingiberaceae), and West African black pepper, Piper guineense Thonn and Schum (Piperaceae). Additional bioassays with host plant volatiles were conducted in the presence of three doses of non‐host plant materials. RESULTS: Both sexes of the weevil showed strong attraction to maize and wheat seed volatiles, but were significantly repelled (P < 0.001) by odours from A. melegueta, Z. officinale and P. guineense. Furthermore, S. zeamais avoided maize and wheat seeds presented in combination with the non‐host plant material at 10% (w/w) and 33% (w/w) levels. CONCLUSIONS: A. melegueta, Z. officinale and P. guineense have the potential for use in the protection of stored grains by resource‐poor farmers with local access to these plants. Copyright © 2009 Society of Chemical Industry 相似文献
106.
Oliveira L Freire CS Silvestre AJ Cordeiro N 《Journal of agricultural and food chemistry》2008,56(20):9520-9524
The chemical composition of the lipophilic extracts of unripe pulp and peel of banana fruit 'Dwarf Cavendish' was studied by gas chromatography-mass spectrometry. Fatty acids, sterols, and steryl esters are the major families of lipophilic components present in banana tissues, followed by diacylglycerols, steryl glucosides, long chain fatty alcohols, and aromatic compounds. Fatty acids are more abundant in the banana pulp (29-90% of the total amount of lipophilic extract), with linoleic, linolenic, and oleic acids as the major compounds of this family. In banana peel, sterols represent about 49-71% of the lipophilic extract with two triterpenic ketones (31-norcyclolaudenone and cycloeucalenone) as the major components. The detection of high amounts of steryl esters (469-24405 mg/kg) and diacylglycerols (119-878 mg/kg), mainly present in the banana peel extract, explains the increase in the abundance of fatty acids and sterols after alkaline hydrolysis. Several steryl glucosides were also found in significative amounts (273-888 mg/kg), particularly in banana pulp (888 mg/kg). The high content of sterols (and their derivatives) in the 'Dwarf Cavendish' fruit can open new strategies for the valorization of the banana residues as a potential source of high-value phytochemicals with nutraceutical and functional food additive applications. 相似文献
107.
Mírian Peixoto Soares da Silva Marta Simone Mendonça Freitas Paulo Cesar Santos Almy Junior Cordeiro de Carvalho Tiago Silva Jorge 《Journal of plant nutrition》2019,42(5):417-427
This study aims to describe macronutrient and boron deficiencies in pepper grown in a hydroponic system in the presence of a substrate during the vegetative and fruiting phases. The experiments were carried out into a greenhouse, and consisted of a randomized block design with eight treatments: complete solution (control) and nitrogen (-N), phosphorus (-P), potassium (-K), calcium (-Ca), magnesium (-Mg), sulfur (-S) and boron (-B) deficient solutions, with four repetitions for each assay. Visual diagnoses of certain macronutrient and boron deficiencies can be applied by farmers to aid in soil management, since they are observed in leaves, while N, P, Ca, S and B deficiencies led to roots symptoms. Pepper fruits showed nutritional deficiency symptoms when grown under N, K, Ca, Mg, S and B deficits. The appearance of nutrient deficiency symptoms in pepper plants occurs in the following order: N, K, P, Mg, S, Ca and B. 相似文献
108.
Exterkoetter Ronan Rozane Danilo Eduardo da Silva Walquiria Chaves Toci Aline Theodoro Cordeiro Gilcelia Aparecida Benassi Simone Frederigi Boroski Marcela 《Journal of Soils and Sediments》2019,19(5):2240-2250
Journal of Soils and Sediments - Glyphosate is the world’s most used herbicide and monitoring glyphosate in the environment is a relevant topic. The present study aims to develop a... 相似文献
109.
Off-axis crustal thickness across and along the east pacific rise within the MELT area 总被引:1,自引:0,他引:1
JP Canales RS Detrick S Bazin AJ Harding JA Orcutt 《Science (New York, N.Y.)》1998,280(5367):1218-1221
Wide-angle seismic data along the Mantle Electromagnetic and Tomography (MELT) arrays show that the thickness of 0.5- to 1. 5-million-year-old crust of the Nazca Plate is not resolvably different from that of the Pacific Plate, despite an asymmetry in depth and gravity across this portion of the East Pacific Rise. Crustal thickness on similarly aged crust on the Nazca plate near a magmatically robust part of the East Pacific Rise at 17 degrees15'S is slightly thinner (5.1 to 5.7 kilometers) than at the 15 degrees55'S overlapping spreading center (5.8 to 6.3 kilometers). This small north-south off-axis crustal thickness difference may reflect along-axis temporal variations in magma supply, whereas the across-axis asymmetry in depth and gravity must be caused by density variations in the underlying mantle. 相似文献
110.
JR Delaney DS Kelley MD Lilley DA Butterfield JA Baross WSD Wilcock RW Embley M Summit 《Science (New York, N.Y.)》1998,281(5374):222-230
Seafloor diking-eruptive events represent the irreducible, quantum events of upper oceanic crustal accretion. They record events by which a large portion of the oceanic crust has formed through geological history. Since 1993, the U.S. Navy's real-time Sound Surveillance System has allowed location of ongoing acoustic signatures of dike emplacement and basalt eruptions at ridge crests in the northeast Pacific. These diking-eruptive events trigger a sequence of related, rapidly evolving physical, chemical, and biological processes. Magmatic volatiles released during these events may provide nutrients for communities of subseafloor microorganisms, some of which thrive in high-temperature anaerobic environments. Many of the organisms identified from these systems are Archaea. If microorganisms can thrive in the water-saturated pores and cracks within deep, volcanically active portions of our planet, other hydrothermally active planets may harbor similar life forms. 相似文献