Contrasting effects of heat shock during in vitro maturation on development of in vitro‐fertilized and parthenogenetic bovine embryos     

Luiz Sergio Almeida Camargo  Fernanda Queiros Costa  Michele Munk  Sabine Wohlres‐Viana  Raquel Varela Serapio  Bruno Campos Carvalho  Paulo Henrique Campos  Alex Cabral Vieira  Luiz Altamiro Garcia Nogueira  Joao Henrique Moreira Viana 《Reproduction in domestic animals》2019,54(10):1357-1365

This study investigated the influence of heat shock during in vitro maturation on embryo development following in vitro fertilization (IVF) or parthenogenesis (Part). Immature bovine cumulus–oocyte complexes were exposed to heat shock (41.0°C) during the first 12 hr of in vitro maturation (IVM), followed by 12 hr at 38.5°C. Control group consisted of in vitro maturation for 24 hr at 38.5°C. Oocytes were in vitro‐fertilized or activated with ionomycin and cultured in vitro for 192 hr post‐in vitro insemination or parthenogenetic activation (hpia). There was an interaction (p < .01) between temperature of IVM and method of oocyte activation (IVF or Part) for cleavage at 48 hpia. Heat shock had a negative impact (p < .01) on cleavage of IVF embryos, whereas no (p > .05) effect was found in the Part embryos. Embryo development towards blastocyst stage at 168 and 192 hpia decreased in both IVF and Part embryos derived from heat‐shocked oocytes. Heat shock increased (p < .05) the apoptotic index in Part blastocysts, but no effect (p > .05) was found in IVF counterparts. Heat shock also down‐regulated the expression of AQP3 (p < .01) and up‐regulated the expression of HSP70.1 (p < .01) in Part blastocysts, whereas it down‐regulated the expression of ATP1A1 (p < .05) in IVF blastocysts. In conclusion, the effects of heat shock during IVM on early embryo cleavage and blastocyst apoptosis are influenced by the method of oocyte activation and expression of some genes can be disturbed in embryos derived from heat‐shocked oocytes.  相似文献   

Reproductive seasonality in Saanen goats kept under tropical conditions     

Balaro  Mario Felipe A.  de Mello  Samuel Guaraná Valverde  da Silva Santos  Alex  Cavalcanti  Luiza Mattos  Almosny  Nádia Regina Pereira  Fonseca  Jeferson F.  Brandão  Felipe Z. 《Tropical animal health and production》2019,51(2):345-353

Tropical Animal Health and Production - This study aimed to verify the reproductive seasonality in Saanen goats from distinct parity orders (nulliparous, primiparous, and pluriparous) throughout an...  相似文献   

Weather-Centric Rangeland Revegetation Planning     

Stuart P. Hardegree  John T. Abatzoglou  Mark W. Brunson  Matthew J. Germino  Katherine C. Hegewisch  Corey A. Moffet  David S. Pilliod  Bruce A. Roundy  Alex R. Boehm  Gwendwr R. Meredith 《Strength and Conditioning Journal》2018,71(1):1-11

Invasive annual weeds negatively impact ecosystem services and pose a major conservation threat on semiarid rangelands throughout the western United States. Rehabilitation of these rangelands is challenging due to interannual climate and subseasonal weather variability that impacts seed germination, seedling survival and establishment, annual weed dynamics, wildfire frequency, and soil stability. Rehabilitation and restoration outcomes could be improved by adopting a weather-centric approach that uses the full spectrum of available site-specific weather information from historical observations, seasonal climate forecasts, and climate-change projections. Climate data can be used retrospectively to interpret success or failure of past seedings by describing seasonal and longer-term patterns of environmental variability subsequent to planting. A more detailed evaluation of weather impacts on site conditions may yield more flexible adaptive-management strategies for rangeland restoration and rehabilitation, as well as provide estimates of transition probabilities between desirable and undesirable vegetation states. Skillful seasonal climate forecasts could greatly improve the cost efficiency of management treatments by limiting revegetation activities to time periods where forecasts suggest higher probabilities of successful seedling establishment. Climate-change projections are key to the application of current environmental models for development of mitigation and adaptation strategies and for management practices that require a multidecadal planning horizon. Adoption of new weather technology will require collaboration between land managers and revegetation specialists and modifications to the way we currently plan and conduct rangeland rehabilitation and restoration in the Intermountain West.  相似文献   

Failure mode and bending moment of canine pancarpal arthrodesis constructs stabilized with two different implant systems     

Wininger FA  Kapatkin AS  Radin A  Shofer FS  Smith GK 《Veterinary surgery : VS》2007,36(8):724-728

Objective— To compare failure mode and bending moment of a canine pancarpal arthrodesis construct using either a 2.7 mm/3.5 mm hybrid dynamic compression plate (HDCP) or a 3.5 mm dynamic compression plate (DCP).
Study Design— Paired in vitro biomechanical testing of canine pancarpal arthrodesis constructs stabilized with either a 2.7/3.5 HDCP or 3.5 DCP.
Sample Population— Paired cadaveric canine antebrachii (n=5).
Methods— Pancarpal arthrodesis constructs were loaded to failure (point of maximum load) in 4-point bending using a materials-testing machine. Using this point of failure, bending moments were calculated from system variables for each construct and the 2 plating systems compared using a paired t-test. To examine the relationship between metacarpal diameter and screw diameter failure loads, linear regression was used and Pearson' correlation coefficient was calculated. Significance was set at P <.05.
Results— HDCP failed at higher loads than DCP for 9 of 10 constructs. The absolute difference in failure rates between the 2 plates was 0.552±0.182 N m, P =.0144 (95% confidence interval: −0.58 to 1.68). This is an 8.1% mean difference in bending strength. There was a significant linear correlation r=0.74 ( P -slope=.014) and 0.8 ( P -slope=.006) between metacarpal diameter and failure loads for the HDCP and 3.5 DCP, respectively.
Conclusion— There was a small but significant difference between bending moment at failure between 2.7/3.5 HDCP and 3.5 DCP constructs; however, the difference may not be clinically evident in all patients.
Clinical Relevance— The 2.7/3.5 HDCP has physical and mechanical properties making it a more desirable plate for pancarpal arthrodesis.  相似文献   

Update on the diagnosis of Haemophilus parasuis infection in pigs and novel genotyping methods   总被引：1，自引：0，他引：1  

Olvera A  Segalés J  Aragón V 《Veterinary journal (London, England : 1997)》2007,174(3):522-529

Haemophilus parasuis causes Gl?sser's disease as well as a number of other diseases in pigs. The diagnosis of H. parasuis-associated disease is usually established by clinical signs, pathological findings and bacterial isolation but diagnosis is complicated by the existence of non-virulent strains and the early colonisation of the upper respiratory tract of healthy piglets. Moreover, several strains can be found on a farm and even within a single animal so it is important to determine the specific strain that is causing the clinical outbreak. Recently, genotyping methods have been developed with the goal of correlating genotype with the degree of virulence of H. parasuis strains. The association between genotype and virulence in H. parasuis is challenging due to the lack of knowledge of the complete genomic sequence and virulence factors of this bacterium.  相似文献   

Combining ability analysis of earliness and yield of potato (<Emphasis Type="Italic">Solanum tuberosum</Emphasis> L.) genotypes in Uganda     

Prossy Namugga  Julia Sibiya  Rob Melis  Alex Barekye 《Euphytica》2018,214(7):116

Potato (Solanum tuberosum L.) is a major food and cash crop mainly grown by small-scale farmers in the highland regions of Uganda. Changing global weather patterns require varieties that are able to grow within the short rainfall cycles and yield optimally under the prevailing conditions. The objectives of this study were to estimate the combining ability effects for early maturity, yield and yield related traits in potato. Eighteen F¹ families generated from two sets of 12 parents using a North Carolina Design II were evaluated for days to 50% flowering, leaf senescence, yield and yield related traits in two different locations. Both additive and non-additive genetic effects influenced the expression of traits. However, additive genetic effects were predominant over the non-additive for most of the traits. The GCA/SCA ratios were 0.68 and 0.78 for days to 50% flowering and average tuber weight. Broad sense heritability estimates were 0.70 for total tuber weight and 0.78 for days to 50% flowering. The predominance of additive genetic effects imply that, genetic gains can be achieved through different selection methods and traits transferred to the respective progenies. Parents Rwangume, 396,038.107, 395,011.2, NKRK19.17, 393,077.54, Kimuri, and 392,657.8 had desirable GCA effects for the number of days to flowering and yield related traits. Families of Rwangume?×?NKRK19.17, 393,077.54?×?395,011.2, 396,038.107?×?Rwangume and 396,038.107?×?395,011.2 had desirable SCA effects for yield and number of days to 50% flowering. The selected parents and families will be subjected to further clonal evaluation and selection.  相似文献   

Environmental influences on Atlantic bluefin tuna (Thunnus thynnus) catch per unit effort in the southern Gulf of St. Lawrence     

Angelia S. M. Vanderlaan  Alex R. Hanke  Joël Chassé  John D. Neilson 《Fisheries Oceanography》2014,23(1):83-100

The Atlantic bluefin tuna (Thunnus thynnus) population in the western Atlantic supports substantial commercial and recreational fisheries. Despite quota establishment and management under the auspices of the International Commission for the Conservation of Atlantic Tunas, only small increases in population growth have been estimated. In contrast to other western bluefin tuna fisheries indices, contemporary estimates of catch per unit effort (CPUE) in the southern Gulf of St. Lawrence have increased rapidly and are at record highs. This area is characterized by the Cold Intermediate Layer (CIL) that is defined by waters <3°C and located at depths of 30–40 m in September. We investigated the influence of several in situ environmental variables on the bluefin tuna fishery CPUE using delta‐lognormal modelling and relatively extensive and consistent oceanographic survey data, as well as dockside monitoring and mandatory logbook data associated with the fishery. Although there is considerable spatial and temporal variation of water mass characteristics, the amount of available habitat in the southern Gulf of St. Lawrence (assuming a > 3°C thermal ambit) for bluefin tuna has been increasing. The percentage of the water column occupied by the CIL was a significant environmental variable in the standardization of CPUE estimates. There was also a negative relationship between the spatial extents of the CIL and the fishery. Properties of the CIL account for variation in the bluefin tuna CPUE and may be a factor in determining the amount of available feeding habitat for bluefin tuna in the southern Gulf of St. Lawrence.  相似文献   

State-of-the-art review of goat TSE in the European Union, with special emphasis on PRNP genetics and epidemiology     

Gabriele Vaccari  Cynthia H. Panagiotidis  Cristina Acin  Simone Peletto  Francis Barillet  Pierluigi Acutis  Alex Bossers  Jan Langeveld  Lucien van Keulen  Theodoros Sklaviadis  Juan J. Badiola  Olivier Andr��oletti  Martin H. Groschup  Umberto Agrimi  James Foster    Wilfred Goldmann 《Veterinary research》2009,40(5)

Scrapie is a fatal, neurodegenerative disease of sheep and goats. It is also the earliest known member in the family of diseases classified as transmissible spongiform encephalopathies (TSE) or prion diseases, which includes Creutzfeldt-Jakob disease in humans, bovine spongiform encephalopathy (BSE), and chronic wasting disease in cervids. The recent revelation of naturally occurring BSE in a goat has brought the issue of TSE in goats to the attention of the public. In contrast to scrapie, BSE presents a proven risk to humans. The risk of goat BSE, however, is difficult to evaluate, as our knowledge of TSE in goats is limited. Natural caprine scrapie has been discovered throughout Europe, with reported cases generally being greatest in countries with the highest goat populations. As with sheep scrapie, susceptibility and incubation period duration of goat scrapie are most likely controlled by the prion protein (PrP) gene (PRNP). Like the PRNP of sheep, the caprine PRNP shows significantly greater variability than that of cattle and humans. Although PRNP variability in goats differs from that observed in sheep, the two species share several identical alleles. Moreover, while the ARR allele associated with enhancing resistance in sheep is not present in the goat PRNP, there is evidence for the existence of other PrP variants related to resistance. This review presents the current knowledge of the epidemiology of caprine scrapie within the major European goat populations, and compiles the current data on genetic variability of PRNP.  相似文献   

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Alex Dugdale  Nicki Grint  & John Burford 《The Journal of small animal practice》2009,50(7):378-379

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Statistical analysis of the effect of multi-stage hot drawing on the thermal shrinkage and crystallographic order of biodegradable aliphatic-aromatic co-polyester fibres     

Basel Younes  Alex Fotheringham  Robert Mather 《Fibers and Polymers》2011,12(6):778-788

Using statistical experimental design, the effects of multi-stage hot drawing process on thermal shrinkage and crystallographic order of linear aliphatic-aromatic co-polyester fibres were statistically analyzed. Thermal shrinkage and fullwidth half-maximum (FWHM) of an X-ray scattering profile of the fibres have been quantitatively assessed, and the direction of increasing or decreasing the significant process parameters has been characterized. It has been found that the number of drawing stages, drawing temperature and relaxing stage ratio affect the shrinkage and crystallographic order together. Plate temperature and the interaction between drawing stages and drawing temperature or drawing ratio have an effect on thermal shrinkage; Spin finish application and relaxing temperature have an effect on crystallographic order. The data analysis has been characterized with regard to the relationship between the studied factors statistically analyzed and the scientific reasons suggested. Factorial statistical analysis simulates the combination of drawing process parameters and the selected as-spun environmentally friendly biodegradable fibre.  相似文献