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Carolina Paula Bianchi Maria F. Gallelli Juan Manuel Herrera Micaela A. Benavente Liliana Rossetto Marcelo Alfredo Aba 《Reproduction in domestic animals》2023,58(1):3-9
Camelids have many unique reproductive features that considerably differ from those of other domestic species. Females are induced ovulators with subsequent development of a corpus luteum (CL) with a short lifespan. Plasma progesterone concentration starts to increase on day 4, peaks on day 8–9 and, in non-pregnant animals, basal concentration is reached around day 10–11 post-induction of ovulation. Luteolytic pulses of prostaglandin F2α (PGF2α) are firstly detected on day 7 or 8 (approximately on day 5–6 after ovulation), with maximal luteolytic peaks observed between days 9 and 11 post-mating, in coincidence with a high endometrial expression of cyclooxygenase 2, a limiting enzyme in prostaglandins synthesis. Unlike other species, oxytocin seems not to be involved in the luteolytic process in these species. The CL is the main source of progesterone secretion, and its function is required to support pregnancy. Despite constant research efforts, aspects of reproduction and maternal recognition of pregnancy in camelids remain not fully understood. A transient decrease and subsequent recovery in plasma progesterone concentration are observed after day 9 post-mating in pregnant animals in association with a pulsatile release of PGF2α and a transitory decrease in CL vascularization. Thus, embryo recognition should occur between days 8 and 12 post-mating. In camels, conceptus tissues exhibit aromatizing activity with the capacity to synthesize large amounts of oestradiol. Similarly, llama blastocysts secrete oestradiol-17β during the preimplantation stage, with a higher production during the elongation period. An increase in the endometrial expression of oestrogen receptor α is also observed on day 12 post-mating. All these evidences suggest that oestrogen could be the signal released by the embryo at the time of its recognition in camelids. Besides, nearly 98% of pregnancies are carried out in the left horn. A decrease in the endometrial expression of mucin 1 and 16 genes has been reported, suggesting that these changes are crucial for successful embryo implantation; however, no differences have been observed between horns. Thus, maternal recognition of pregnancy in camelids is a particularly complex process that must occur in a concise time to allow the rescue of the CL and embryo survival. 相似文献
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Laura Arru Sara Rognoni Micaela Baroncini Piera Medeghini Bonatti Pierdomenico Perata 《Euphytica》2004,140(1-2):33-38
Summary With the aim to examine its potential as a renewable resource to decontaminate polluted soils, electron microscopy combined with X-ray microanalysis was used to investigate the localization of copper in Cannabis sativa grown in hydroponic copper-rich culture. Cu was found to accumulate preferentially in the upper leaf epidermal cells; it was also detected in spiculae and in abaxial trichomes too. Primary bast fibres seem to be not involved in copper accumulation. 相似文献
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Armbrust EV Berges JA Bowler C Green BR Martinez D Putnam NH Zhou S Allen AE Apt KE Bechner M Brzezinski MA Chaal BK Chiovitti A Davis AK Demarest MS Detter JC Glavina T Goodstein D Hadi MZ Hellsten U Hildebrand M Jenkins BD Jurka J Kapitonov VV Kröger N Lau WW Lane TW Larimer FW Lippmeier JC Lucas S Medina M Montsant A Obornik M Parker MS Palenik B Pazour GJ Richardson PM Rynearson TA Saito MA Schwartz DC Thamatrakoln K Valentin K Vardi A Wilkerson FP Rokhsar DS 《Science (New York, N.Y.)》2004,306(5693):79-86
Diatoms are unicellular algae with plastids acquired by secondary endosymbiosis. They are responsible for approximately 20% of global carbon fixation. We report the 34 million-base pair draft nuclear genome of the marine diatom Thalassiosira pseudonana and its 129 thousand-base pair plastid and 44 thousand-base pair mitochondrial genomes. Sequence and optical restriction mapping revealed 24 diploid nuclear chromosomes. We identified novel genes for silicic acid transport and formation of silica-based cell walls, high-affinity iron uptake, biosynthetic enzymes for several types of polyunsaturated fatty acids, use of a range of nitrogenous compounds, and a complete urea cycle, all attributes that allow diatoms to prosper in aquatic environments. 相似文献
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Giorgi M Cuniberti B Ye G Barbero R Sgorbini M Vercelli C Corazza M Re G 《Veterinary journal (London, England : 1997)》2011,190(1):143-149
Tepoxalin is a non-steroidal anti-inflammatory drug with analgesic, anti-inflammatory, and antipyretic properties and has been recently introduced into veterinary medicine. The aim of this study was to evaluate the pharmacokinetic/pharmacodynamic (PK/PD) profile of tepoxalin to assess whether it would be suitable for clinical use in horses. Six female fasting/fed horses were given 10mg/kg tepoxalin orally in a cross-over study. After administration, tepoxalin underwent rapid and extensive hydrolytic conversion to its carboxylic acid metabolite RWJ-20142. In animals that had been fed, the plasma concentrations of tepoxalin were undetectable, whereas in fasting animals they were close to the limit of quantification of the method. No differences between the fasting/fed groups in RWJ-20142 plasma concentrations were shown. Tepoxalin showed a strong and long-lasting ex vivo inhibitory activity against cyclooxygenase (COX)-1, mainly due to its main metabolite RWJ-20142. Tepoxalin and RWJ-20142 do not seem to possess either COX-2 or 5-lipoxygenase inhibitory activity in the horse. These features suggest that the drug is a selective COX-1 inhibitor in horses, with no significant anti-inflammatory activity. Thus, its long term use in equine practice could be of concern. 相似文献
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Valentina Vitale Rita Balocchi Maurizio Varanini Micaela Sgorbini Alberto Macerata Claudio Sighieri Paolo Baragli 《Journal of Veterinary Behavior: Clinical Applications and Research》2013,8(5):400-403
Analysis of heart rate variability (HRV) is a noninvasive approach for investigating the sympathovagal balance of the autonomic nervous system. In recent years, HRV has been increasingly evaluated in animal research. In horses, it has been suggested that basal resting conditions can be achieved by restraining them. The aim of this study was to verify how restriction of movement influences HRV i2n horses. Ten healthy standardbred mares were used to measure the electrocardiographic signal under 2 conditions: free to move in the stall and restrained in the stock. Results indicate that the restriction of movement is associated with increased nervous system sympathetic activity not consistent with resting conditions. 相似文献
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OBJECTIVE: To identify and quantify ocular fungi from healthy donkeys living in the center of Italy. ANIMALS STUDIED: One hundred and two Amiata donkeys were examined. PROCEDURES: Conjunctival swabs from both eyes were seeded onto Sabouraud dextrose agar (SDA) and malt extract agar (MEA), and incubated at 25 degrees C over a 10-day period. Filamentous fungi identification was achieved to the genus level; yeast colonies were identified for macro-micromorphologic and physiological characteristics. RESULTS: Eighty-one donkeys out of 102 (79.4%) were positive for fungi; 47/102 (46.1%) had positive cultures from both eyes. Most frequently recovered fungal genera were Aspergillus spp., Penicillium spp., Cladosporium spp., Acremonium spp. Different fungal genera and/or species were recovered from the same donkey in 43 cases (42.1%). Yeasts were isolated from five subjects; the yeasts were never associated with molds. The number of colony forming units (CFU) ranged from 1 to 100. CONCLUSIONS: Aspergillus was the most commonly isolated fungal genus (33%). This result agrees with the findings of similar surveys carried out in horses. There was a remarkable presence of fungi and perfect forms. These observations may be explained by the optimal conditions for presence and development of fungi in the conjunctival fornix microenvironment in Amiata donkeys. 相似文献
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BACKGROUND: The worldwide need to produce an inexpensive and abundant food supply for a growing population is a great challenge that is further complicated by concerns about risks to environmental stability and human health triggered by the use of pesticides. The result is the ongoing development of alternative pest control strategies, and new, lower‐risk insecticidal molecules. Among the recent technological advances in agricultural science, nanotechnology shows considerable promise, although its development for use in crop protection is in its initial stages. RESULTS: This study reports for the first time the insecticidal effect of nanostructured alumina. Two species were used as model organisms, Sitophilus oryzae L. and Rhyzopertha dominica (F.), which are major insect pests in stored food supplies throughout the world. Both species experienced significant mortality after 3 days of continuous exposure to treated wheat. Nine days after treatment, the median lethal doses (LD50) observed ranged from 127 to 235 mg kg?1. CONCLUSION: Comparison of these results with recommended rates for commercial insecticidal dusts suggests that inorganic nanostructured alumina may provide a cheap and reliable alternative for control of insect pests. This study expands the frontiers for nanoparticle‐based technologies in pest management. Further research is needed to identify its mode of action and its non‐target toxicity, and to determine the potential of other nanostructured materials as pest control options for insects. Copyright © 2010 Society of Chemical Industry 相似文献
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Rafael Ramírez‐Vasquez Andreina Cesari Micaela B. Greco Adriana Cano Federico Hozbor 《Reproduction in domestic animals》2019,54(12):1621-1629
Seminal plasma (SP) proteins interact with sperm plasma membrane (PM) modulating its functionality. It has been shown that SP proteins can reverse the damage caused by freeze‐thaw; however in these studies, SP has been added to washed sperm (i.e., cells depleted from homologous SP and extender). The aim of the current study was to assess whether the egg yolk‐based extender (EY) modifies SP ability to ameliorate sperm parameters in frozen‐thawed ram spermatozoa. Ejaculates were diluted in EY or soybean lecithin‐based extender (SL) and evaluated before and after freezing to measure the cell damage according to the extender. Even when all classical parameters decreased after freezing, as expected (p < .05), there was no effect of the extender. SP treatment was applied after freeze‐thaw. Sperm were incubated with SP (20% v/v) in the presence of either EY or SL, and sperm parameters were assessed after thawing compared with the same treatments after Percoll sperm selection (washed). Treatments with 20% SP improved sperm total and progressive motility compared with controls regardless of washing and extender (p < .05); however, washed sperm showed higher percentage of total sperm motility compared with those unwashed (p < .05). Moreover, treatment with 20% SP showed significantly higher percentages of PM integrity, sperm with intact acrosomes, integrity of chromatin and non‐capacitated sperm in samples diluted with EY when washed before treatment compared with the other conditions (p < .05). It was concluded that the presence of the extenders and particularly egg yolk alters the SP capacity to reduce the cryodamage. 相似文献