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Lauren G Chukrallah Aditi Badrinath Kelly Seltzer Elizabeth M Snyder 《Journal of animal science》2021,99(3)
Ruminants are major producers of meat and milk, thus managing their reproductive potential is a key element in cost-effective, safe, and efficient food production. Of particular concern, defects in male germ cells and female germ cells may lead to significantly reduced live births relative to fertilization. However, the underlying molecular drivers of these defects are unclear. Small noncoding RNAs, such as piRNAs and miRNAs, are known to be important regulators of germ-cell physiology in mouse (the best-studied mammalian model organism) and emerging evidence suggests that this is also the case in a range of ruminant species, in particular bovine. Similarities exist between mouse and bovids, especially in the case of meiotic and postmeiotic male germ cells. However, fundamental differences in small RNA abundance and metabolism between these species have been observed in the female germ cell, differences that likely have profound impacts on their physiology. Further, parentally derived small noncoding RNAs are known to influence early embryos and significant species-specific differences in germ-cell born small noncoding RNAs have been observed. These findings demonstrate the mouse to be an imperfect model for understanding germ-cell small noncoding RNA biology in ruminants and highlight the need to increase research efforts in this underappreciated aspect of animal reproduction. 相似文献
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A biological simulation model and a linear programming model were interfaced to determine production efficiencies and the optimal carrying capacity of a cow-calf producer in East Texas and to compare net returns to the model farm, given alternative tame forage systems and management practices. Experimental data both on forage systems and on livestock were used to verify and validate the simulated herds. The results showed that (1) of the three tame forage systems analyzed, warm-season perennial forages provided a relatively higher carrying capacity/ha, whereas a mix of both warm- and cool-season forages that allows year-round grazing gave relatively higher net returns/ha to management; (2) nutritional stress during winter months decreased animal performance proportionately more than it decreased feed costs; and (3) although spring-calving herds included more animals than corresponding fall-calving herds on the same land area, fall-calving herds produced more liveweight sales and generally higher net returns. 相似文献
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Vivek Ahluwalia Ritu Sisodia Suresh Walia Om P. Sati Jitendra Kumar Aditi Kundu 《Journal of pest science》2014,87(2):341-349
Essential oils from inflorescences and roots of Eupatorium adenophorum Spreng (Asteraceae) have been investigated for their antimicrobial, phytotoxic and antioxidant activities. Based on GC–MS, the oil from inflorescences is dominated by sesquiterpenes (55.9 %) with γ-cadinene (18.4 %), γ-muurolene (11.7 %), 3-acetoxyamorpha-4,7(11)-diene-8-one (7.4 %) and bornyl acetate (6.3 %) as the major constituents. The oil obtained from the roots contained both sesquiterpenes (34.3 %) and monoterpenes (32.5 %) in almost equal proportions with E,E-cosmene (19.9 %), γ-muurolene (10.1 %), isothymol (7.5 %), β-cadinene (7.0 %) and α-phellandren-8-ol (5.9 %) as the major constituents. Both oils exhibited significant antifungal activity against five phytopathogenic fungi. The inflorescence oil showed higher antibacterial activity against Klebsiella pneumoniae, while the root oil was more effective against Staphylococcus aureus. The oils strongly inhibited or delayed germination and seedling growth of the weed Phalaris minor in a dose-dependent manner. As evidenced by a DPPH assay, the essential oils also exhibited significant free radical scavenging activity. 相似文献
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Kar A Jacquier JC Morgan DJ Lyng JG McKenna BM 《Journal of agricultural and food chemistry》2005,53(21):8259-8264
The influence of the lipid extraction process on both macroscopic and microscopic characteristics of nonwaxy rice starch gelatinization in excess water was examined. Surface lipids extraction did not change the thermodynamics of starch gelatinization but lead to a significant reduction (33%) in the enthalpy of starch-lipid complex melting at high temperature, resulting in less viscous dispersions. Internal lipid extraction using hot aqueous alcoholic solutions resulted in an irreversible increase in starch granule diameter (50% increase in D[4,3]) and a dramatic change in cooking characteristics of the starch. Instead of the bimodal swelling observed for native nonwaxy rice starch, only one broad transition in swelling, solubility, granule size, and viscosity was observed in the case of the totally defatted starch. While the total removal of lipids resulted in a slight increase in starch swelling at intermediate temperatures, the harshness of the process caused irreparable changes leading to notably lower swelling at high temperatures. 相似文献
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Giovani Trevisan Aditi Sharma Phillip Gauger Karen M. Harmon Jianqiang Zhang Rodger Main Michael Zeller Leticia C. M. Linhares Daniel C. L. Linhares 《Journal of veterinary diagnostic investigation》2021,33(5):920
The genetic diversity of porcine reproductive and respiratory syndrome virus (PRRSV) increases over time. In 1998, restriction-fragment length polymorphism (RFLP) pattern analysis was introduced to differentiate PRRSV wild-type strains from VR2332, a reference strain from which a commercial vaccine (Ingelvac PRRS MLV) was derived. We have characterized here the PRRSV genetic diversity within selected RFLP families over time and U.S. geographic space, using available ISU-VDL data from 2007 to 2019. The 40,454 ORF5 sequences recovered corresponded to 228 distinct RFLPs. Four RFLPs [2-5-2 (21.2%), 1-7-4 (15.6%), 1-4-4 (11.8%), and 1-8-4 (9.9%)] represented 58.5% of all ORF5 sequences and were used for cluster analysis. Over time, there was increased detection of RFLPs 2-5-2, 1-7-4, 1-3-4, 1-3-2, and 1-12-4; decreased detection of 1-4-2, 1-18-4, 1-18-2, and 1-2-2; and different detection trends for 1-8-4, 1-4-4, 1-26-1, 1-22-2, and 1-2-4. An over-time cluster analysis revealed a single cluster for RFLP 2-5-2, supporting that sequences within RFLP 2-5-2 are still relatively conserved. For 1-7-4, 1-4-4, and 1-8-4, there were multiple clusters. State-wise cluster analysis demonstrated 4 main clusters for RFLP 1-7-4 and 1-8-4, and 6 for RFLP 1-4-4. For the other RFLPs, there was a significant genetic difference within them, particularly between states. RFLP typing is limited in its ability to discriminate among different strains of PRRSV. Understanding the magnitude of genetic divergence within RFLPs helps develop PRRSV regional control programs, placement, herd immunization strategies, and design of appropriate animal movements across borders to minimize the risk of PRRSV transmission. 相似文献
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Aditi Shenoy Jill F. Johnstone Eric S. Kasischke Knut Kielland 《Forest Ecology and Management》2011,261(3):381-390
There has been a recent increase in the frequency and extent of wildfires in interior Alaska, and this trend is predicted to continue under a warming climate. Although less well documented, corresponding increases in fire severity are expected. Previous research from boreal forests in Alaska and western Canada indicate that severe fire promotes the recruitment of deciduous tree species and decreases the relative abundance of black spruce (Picea mariana) immediately after fire. Here we extend these observations by (1) examining changes in patterns of aspen and spruce density and biomass that occurred during the first two decades of post-fire succession, and (2) comparing patterns of tree composition in relation to variations in post-fire organic layer depth in four burned black spruce forests in interior Alaska after 10-20 years of succession. We found that initial effects of fire severity on recruitment and establishment of aspen and black spruce were maintained by subsequent effects of organic layer depth and initial plant biomass on plant growth during post-fire succession. The proportional contribution of aspen (Populus tremuloides) to total stand biomass remained above 90% during the first and second decades of succession in severely burned sites, while in lightly burned sites the proportional contribution of aspen was reduced due to a 40-fold increase in spruce biomass in these sites. Relationships between organic layer depth and stem density and biomass were consistently negative for aspen, and positive or neutral for black spruce in all four burns. Our results suggest that initial effects of post-fire organic layer depths on deciduous recruitment are likely to translate into a prolonged phase of deciduous dominance during post-fire succession in severely burned stands. This shift in vegetation distribution has important implications for climate-albedo feedbacks, future fire regime, wildlife habitat quality and natural resources for indigenous subsistence activities in interior Alaska. 相似文献
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P Guichard A Desfosses A Maheshwari V Hachet C Dietrich A Brune T Ishikawa C Sachse P Gönczy 《Science (New York, N.Y.)》2012,337(6094):553
Centrioles and basal bodies are essential for the formation of cilia, flagella, and centrosomes. They exhibit a characteristic ninefold symmetry imparted by a cartwheel thought to contain rings of SAS-6 proteins. We used cryoelectron tomography to investigate the architecture of the exceptionally long cartwheel of the flagellate Trichonympha. We found that the cartwheel is a stack of central rings that exhibit a vertical periodicity of 8.5 nanometers and is able to accommodate nine SAS-6 homodimers. The spokes that emanate from two such rings associate into a layer, with a vertical periodicity of 17 nanometers on the cartwheel margin. Thus, by using the power of biodiversity, we unveiled the architecture of the cartwheel at the root of the ninefold symmetry of centrioles and basal bodies. 相似文献
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Aditi Jana Sonali Sinha Manivannan Jothiramajayam Anish Nag 《Archives of Agronomy and Soil Science》2017,63(10):1443-1453
Leaching of heavy metals from coal fly ash dumpsites is an environmental threat often polluting both groundwater and surface water. This led to a detailed investigation on the cyto-genotoxicity and oxidative stress associated with the fly ash leachate (FL). Allium cepa L. bulbs were exposed to three concentrations of FL. Response to FL resulted in a reduction of root growth, inhibition of cell viability by up to 50%, and decrease in mitotic indices (control: 10.27; FA:water 1:4–4.52) with increased frequency of chromosome aberrations (5.7 fold) and bi-nucleate cells. Results of comet assay indicated that approximately sixfold increase in genotoxicity of FL was congruent with the endpoints of oxidative stress evaluated. The malondialdehyde content, superoxide dismutase, guaiacol peroxidase and glutathione-S-transferase activities were elevated in the treated plants in a dose dependent manner. The elemental analysis of FL showed the presence of heavy metals like cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), cadmium (Cd), nickel (Ni), lead (Pb) and zinc (Zn). The study demonstrated that FL can cause adverse effects to the plants. Therefore, the disposal of coal fly ash should be handled with caution and prevented from contaminating the surroundings. 相似文献
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