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排序方式: 共有170条查询结果,搜索用时 15 毫秒
31.
32.
Analytical validation of a flow cytometric protocol for quantification of platelet microparticles in dogs
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33.
Supplementation with sunflower seeds in beef cattle did not impact on oocyte and in vitro embryo production
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AL Baltazar GM de Mattos BM Ropelli SMG Firetti C Castilho G Pugliesi MBC Maldonado M Binelli JOF Silva GC Lupatini BS Lafuente CMB Membrive 《Reproduction in domestic animals》2018,53(3):801-808
Supplementation with compounds rich in linoleic acid, including sunflower seed supplementation, promotes increase in conception rates in cows. We aimed to evaluate whether the sunflower seed (linoleic acid source) supplementation in beef donor females alters the plasma concentrations of cholesterol, triglycerides, HDL and LDL, increases the number and quality of oocytes, increases the cleavage rates and determines an improvement in number and quality of in vitro produced blastocysts. Thus, Nelore females were divided into two groups of 15 animals to receive supplementation with or without sunflower seed for 57 days. Females underwent follicular aspiration and the oocytes were subjected to in vitro embryo production. There was no difference (p > .1) between control group and group supplemented with sunflower seed on the number of displayed follicles; number of aspired oocytes; recovery rate; cleavage rate; number of embryos; number of blastocysts; embryos number of grades I and II; plasma concentrations of total cholesterol, triglycerides; HDL and LDL. Therefore, sunflower seed supplementation in oocyte donors did not increase the number and quality of oocytes, cleavage rates and the number and quality of blastocysts produced in vitro. 相似文献
34.
Effect of body condition score and reuse of progesterone‐releasing intravaginal devices on conception rate following timed artificial insemination in Nelore cows
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LL Pereira AP Ferreira WG Vale LR Serique KAL Neves AC Morini BM Monteiro AHH Minervino 《Reproduction in domestic animals》2018,53(3):624-628
This study had the aim of investigating the efficiency of timed artificial insemination (TAI) through the progesterone‐releasing intravaginal device (PRID), used in new condition and for the second and third times in Nelore cows. The effects of device reuse and body condition score (BCS) on the conception rate (CR) were evaluated in 1,122 multiparous Nelore cows (mean BCS of 2.7 ± 0.4), which were randomly distributed into three groups that received new (n = 330), once (n = 439) and twice used (n = 353) PRID. Among the 1,122 females that underwent TAI, 573 became pregnant, thus representing an overall CR of 51.06%. Cows with BCS between 2.75 and 4.0 had greater (p < .0001) CR (69.75%) than cows with BSC of 2.0–2.5 (32.98%). It was observed that the CR through using PRID was 60.00%, 51.71% and 41.93% for new, once and twice used PRID, respectively, with difference between all groups (p < .0001). Under tropical conditions, animals with BCS greater than 2.5 had a higher CR, and the CR decreased proportionally with the number of times that the PRID had been used. 相似文献
35.
Long‐term crop rotation trials were designed to assess sustainability of alternatives to traditional fallow and monocropping. The trial described here (6 years) involved wheat (Triticum aestivum L.) in rotation with lentil (Lens culinaris L.), forage vetch (Vicia sativa), pasture medic (Medicago spp.), fallow and watermelon (Citrullus vulgaris). Barley (Hordeum vulgare L.) was compared with wheat for an additional 2 years. Cereal grain and straw yields were highest with fallow and watermelon followed by vetch, lentil and medic; the latter showed no differential effect of variable grazing intensity. Fertilizer N increased yields except in the low‐rainfall years (less than 250 mm). Barley out‐yielded wheat in terms of grain, but not straw. Medic yielded highest in dry matter, whereas lentil produced highest seed yield. Despite the difficulty of assessing crop and animal‐oriented rotations because of non‐commonality of outputs, economic considerations are foremost, but other benefits of rotations (soil quality, water‐use relations) are also relevant to the overall assessment of cereal‐based Mediterranean rotations. The study suggested barley rather than wheat as the desired cereal in rotation with legumes in this marginal‐rainfall (350 mm) environment and provided support for the viability of vetch and lentil in the cropping system. Given the importance of sheep in the region’s farming system, vetch is likely to have a major role in crop rotations. 相似文献
36.
Conifers have evolved constitutive and inducible defense mechanisms to help in both wound healing and defense against attack by bark beetles and other organisms. These defenses include oleoresin, phenolics, and static structures in secondary phloem, such as lignified cells and calcium oxalate crystals, that create physical barriers. We used a phylogenetic approach to investigate the defense anatomy of conifer stems of 13 species from five families following treatment with methyl jasmonate (MJ), a compound that induces defense responses in stems of several Pinaceae species. Methyl jasmonate induced a response similar to wounding except that the response was not accompanied by lesion formation, necrosis or a hypersensitive response. In the Pinaceae species studied, MJ induced polyphenolic parenchyma (PP) cell activation and xylem traumatic resin duct (TD) formation. Members of the Taxodiaceae, which are not known to produce large quantities of resin, showed massive xylem TD formation and surface resinosis following MJ treatment. Treatment with MJ caused members of the Araucariaceae and Cupressaceae to form axial phloem resin ducts but not xylem ducts, whereas Podocarpaceae species showed no induction of resin-producing structures. All species treated with MJ showed phenolic deposition in PP cells, and early lignification of phloem fibers was observed in most of the non-Pinaceae species. We conclude that, although evolution of resin-producing structures occurred independently in conifer lineages, MJ seems to induce resin production regardless of tissue location, as well as inducing deposition of phenolic compounds. Co-evolution of conifer defensive strategies and bark beetle pests is discussed. 相似文献
37.
The main goal of our work is to quantify differences in the rate of ossification in post-cranial Iberian ibex skeletons, related to sex. Another objective is to improve criteria for assessing the sex of post-cranial bones by combining the degree of ossification of the distal epiphysis and biometrical data. Forty Capra pyrenaica skeletons were examined in order to determine the degree of ossification by means of an Ossification Index. Our results evidence that sexual differences in the rate of ossification become visible at 6 months of age. On average, females complete their bone development 2 years before males do. Finally, by means of lineal classification functions which take into account both biometrical and anatomical criteria, we can achieve, in average, a 95.5% of correct sex discrimination within a sample consisting of ibex metacarpi and metatarsi from individuals aging from <1 to 12 years. Therefore, we conclude that the rhythm of ossification in the post-cranial skeleton of C. pyrenaica may be used as a criterion for assessing the sex of skeletal remains and could be applicable to other dimorphic ungulates. Nevertheless, the results obtained for specimens belonging to a particular population may have limited application to other populations with different medium sizes and living at particular densities within habitats with variable quality. 相似文献
38.
Grossmann K Christiansen N Looser R Tresch S Hutzler J Pollmann S Ehrhardt T 《Pest management science》2012,68(4):494-504
BACKGROUND: For novel herbicides identified in greenhouse screens, efficient research is important to discover and chemically optimise new leads with new modes of action (MoAs). RESULTS: The metabolic and physiological response pattern to a herbicide can be viewed as the result of changes elicited in the molecular and biochemical process chain. These response patterns are diagnostic of a herbicide's MoA. At the starting point of MoA characterisation, an array of bioassays is used for comprehensive physiological profiling of herbicide effects. This physionomics approach enables discrimination between known, novel or multiple MoAs of a compound and provides a first clue to a new MoA. Metabolic profiling is performed with the use of treated Lemna paucicostata plants. After plant extraction and chromatography and mass spectrometry, changes in levels of approximately 200 identified and 300 unknown analytes are quantified. Check for known MoA assignment is performed by multivariate statistical data analyses. Distinct metabolite changes, which can direct to an affected enzymatic step, are visualised in a biochemical pathway view. Subsequent target identification includes metabolite feeding and molecular, biochemical and microscopic methods. CONCLUSION: The value of this cascade strategy is exemplified by new herbicides with MoAs in plastoquinone, auxin or very‐long‐chain fatty acid synthesis. Copyright © 2011 Society of Chemical Industry 相似文献
39.
S Nandi V Girish Kumar HS Ramesh BM Manjunatha PSP Gupta 《Reproduction in domestic animals》2009,44(1):74-79
Studies were conducted to examine the effects of the cyclicity and the presence of a dominant follicle (DF) in ovary on the recovery and in vitro growth of pre-antral follicles (PFs) in sheep and buffalo. Small pre-antral follicles (SPFs, 100–250 μm) and large pre-antral follicles (LPFs, 250–450 μm) were isolated from slaughterhouse ovaries in the breeding seasons by a mechanical and enzymatic method. The sheep and buffalo PFs were cultured in vitro for 6 and 15 days, respectively, and examined for their growth, survival and antrum formation rates and growth rates of oocytes in cultured pre-antral follicles. The follicles of the sheep and buffalo were recovered and cultured simultaneously within replicates. The recovery rates (number per ovary) of both SPFs and LPFs were significantly (p < 0.05) higher in cyclic ewes (SPFs: 22.0 ± 3.3 vs 12.1 ± 2.6 and LPFs: 16.0 ± 3.6 vs 9.2 ± 1.8) and buffaloes (SPFs: 9.2 ± 1.3 vs 4.1 ± 1.0 and LPFs: 10.3 ± 2.7 vs 5.4 ± 0.7) compared with those recovered from acyclic ones. Presence of a DF in ovary significantly (p < 0.05) reduced the recovery rates of LPFs in ewes (9.06 ± 2.7 vs 16.4 ± 3.8) but had no effect in buffalo. Cyclicity of animals or follicular dominance had no effects on in vitro growth, survival and antrum formation rates and growth rates of oocytes in cultured PFs of SPFs and LPFs in both sheep and buffalo. The in vitro growth, survival and antrum formation rates of LPFs and growth rates of oocytes in cultured LPFs were significantly (p < 0.05) higher than those observed in SPFs in both sheep and buffalo. The overall recovery and growth rates of the PFs were lower in buffaloes compared with ewes. 相似文献
40.
Björgólfur Hávardsson Albert K. Imsland Rune Christiansen 《Journal of the World Aquaculture Society》1999,30(2):208-218
The aim of this study was to investigate the long term development of carotenoid concentration in gonads and gonad development of green sea urchins reared at different temperatures and fed formulated feed containing dwerent levels of astaxanthin. Urchins, sampled from a natural population, were reared under two different temperature regimes (7 C and 12 C) and fed formulated feed containing 0, 100 and 500 mg astaxanthin/kg feed, respectively. The study lasted 112 d. Astaxanthin was detected in the groups fed feed containing astaxanthm, but in low quantities. No effect of temperature was observed on the retention of astaxanthin. Echinenone values declined throughout the study, probably due to the lack of suitable metabolic precursor for production of echinenone. Water and lipid concentration in the gonads increased throughout the study indicating the progressions of gametogenesis and the generally improved nutritional status of the animals. No significant difference in gonad index (GI) due to treatment was observed but GI varied between the sexes with male GI increasing significantly faster compared to females. 相似文献