Outbreak of rabbit hemorrhagic disease virus 2 in the southwestern United States: first detections in southern California     

Javier Asin  Akinyi C. Nyaoke  Janet D. Moore  Viviana Gonzalez-Astudillo  Deana L. Clifford  Emma L. Lantz  Andrea B. Mikolon  Kimberly A. Dodd  Beate Crossley  Francisco A. Uzal 《Journal of veterinary diagnostic investigation》2021,33(4):728

An outbreak of rabbit hemorrhagic disease virus 2 (RHDV2)-associated disease occurred in the southwestern United States following its first detection in New Mexico in March 2020. The disease spread throughout several states and was diagnosed for the first time in California on May 11, 2020, in a black-tailed jackrabbit (Lepus californicus). The following day, the California Department of Food and Agriculture (CDFA) issued an order banning the entrance into California of several lagomorph species and their products from any state in which the disease had been detected in the last 12 mo. RHDV2 is a threat to wild lagomorph species in California, including the endangered riparian brush rabbit (Sylvilagus bachmani riparius). Therefore, the California Department of Fish and Wildlife (CDFW) started tracking any mortality event in wild lagomorph populations. As of August 9, 2020, RHDV2 had been detected in wild and domestic lagomorphs of several counties in southern California that were submitted to the California Animal Health and Food Safety laboratory system by the CDFA or the CDFW. These positive cases included 2 additional black-tailed jackrabbits and 3 desert cottontail rabbits (Sylvilagus audubonii). In addition, the infection spilled over to domestic populations, whereby it was confirmed on July 10, 2020, in a domestic rabbit (Oryctolagus cuniculus).  相似文献   

A de novo reciprocal chromosomal translocation t(3;6)(p14;q26) in the black Lucano pig     

Viviana Genualdo  Cristina Rossetti  Alfredo Pauciullo  Petra Musilova  Domenico Incarnato  Angela Perucatti 《Reproduction in domestic animals》2020,55(6):677-682

In the past two decades, several cytogenetic screening programmes identified different chromosome rearrangements in pig, most of which represented by reciprocal translocation (rcp). This chromosome abnormality does not involve the variation in the number of chromosomes, but only the rearrangement of genetic material, resulting in phenotypically normal carriers with fertility problems. During an occasional cytogenetic screening, a new reciprocal translocation was detected in the black Lucano pig native breed. We analysed 15 animals reared by a family-run piggery in Basilicata region (Southern Italy). After karyotyping, four pigs (two boars and two sows) revealed two unpaired chromosomes. Analysis of the RBA karyotype and the dual-colour FISH technique confirmed that these pigs showed the same reciprocal translocation involving the chromosomes SSC3 and SSC6. The precise location of breakpoints was identified by RBH-FISH t(3;6)(p14;q26), whereas the analysis of the pedigree showed a case of Mendelian inheritance within a family, after the de novo occurrence of the new rcp. Considering the consequences of the rcp on the fertility, this study points out the importance of the cytogenetic screening in the native breeds for the safeguard of the genetic biodiversity and the sustainability of the rural areas.  相似文献   

Maize response to broadcast flaming at different growth stages: Effects on growth,yield and yield components     

Santiago M. Ulloa  Avishek Datta  Chris Bruening  Brian Neilson  Jared Miller  George Gogos  Stevan Z. Knezevic 《European Journal of Agronomy》2011,34(1):10-19

Weed management is a major constraint in organic crop production. Propane flaming could be an additional tool for weed control in organic maize (Zea mays L.) production. However, tolerance of maize to broadcast flaming must be determined first to optimize the use of propane. Field experiments were conducted at the Haskell Agricultural Laboratory of the University of Nebraska, Concord, NE in 2008 and 2009 to determine maize response to five propane doses applied at three growth stages of V2 (2-leaf), V5 (5-leaf) and V7 (7-leaf). The propane doses tested were 0, 13, 24, 44 and 85 kg ha^?1. Flaming treatments were applied utilizing a custom built research flamer mounted on the back of a four-wheeler moving at a constant speed of 6.4 km h^?1. The response of maize to propane flaming was evaluated in terms of visual crop injury (1, 7, 14 and 28 days after treatment—DAT), effects on dry matter (14 DAT), yield components (plants m^?2, ears plant^?1, kernels cob^?1 and 1000-kernel weight) and grain yield. The response of different growth stages of maize to propane doses was described by log–logistic models. Overall, maize response to broadcast flaming varied among growth stages and propane doses. In general, maize at V5 was the most tolerant stage for broadcast flaming, whereas V2 stage was the most susceptible to flaming resulting in the highest visual crop injury ratings, dry matter reductions and the largest loss of yield and its components. At 28 DAT, the maximum visual crop injury rating of 7% was estimated for flaming done at V5 stage compared to significantly higher injuries of 43% and 12% for V2 and V7 growth stages, respectively. An arbitrarily assigned 2.5% yield reduction was evident with 33, 16 and 11 kg ha^?1 of propane for V5, V2 and V7 growth stages, respectively, suggesting that maize flamed at V5 stage can tolerate higher dose of propane for the same yield reduction compared to other growth stages. Moreover, the maximum yield reductions with the highest propane dose of 85 kg ha^?1 were 3% for V5, 11% for V7 and 17% for V2 stage. Based on these results, flaming has a potential to be used effectively in organic maize production when conducted properly at V5 stage. However, there are both benefits and concerns associated with the use of flame weeding. The preservation of the soil from erosion and the protection of the surface and underground water from chemical pollution can be seen as benefits, while the concerns include higher energy use, and the release of greenhouse gasses.  相似文献   

Impacts of atmospheric anthropogenic nitrogen on the open ocean   总被引：3，自引：0，他引：3  

Duce RA  LaRoche J  Altieri K  Arrigo KR  Baker AR  Capone DG  Cornell S  Dentener F  Galloway J  Ganeshram RS  Geider RJ  Jickells T  Kuypers MM  Langlois R  Liss PS  Liu SM  Middelburg JJ  Moore CM  Nickovic S  Oschlies A  Pedersen T  Prospero J  Schlitzer R  Seitzinger S  Sorensen LL  Uematsu M  Ulloa O  Voss M  Ward B  Zamora L 《Science (New York, N.Y.)》2008,320(5878):893-897

Increasing quantities of atmospheric anthropogenic fixed nitrogen entering the open ocean could account for up to about a third of the ocean's external (nonrecycled) nitrogen supply and up to approximately 3% of the annual new marine biological production, approximately 0.3 petagram of carbon per year. This input could account for the production of up to approximately 1.6 teragrams of nitrous oxide (N2O) per year. Although approximately 10% of the ocean's drawdown of atmospheric anthropogenic carbon dioxide may result from this atmospheric nitrogen fertilization, leading to a decrease in radiative forcing, up to about two-thirds of this amount may be offset by the increase in N2O emissions. The effects of increasing atmospheric nitrogen deposition are expected to continue to grow in the future.  相似文献   

Timing and propane dose of broadcast flaming to control weed population influenced yield of sweet maize (Zea mays L. var. rugosa)     

Santiago M. Ulloa  Avishek Datta  Goran Malidza  Robert Leskovsek  Stevan Z. Knezevic 《Field Crops Research》2010

Farmers are interested to produce sweet maize under organic production systems and propane flaming could be a potential alternative tool for weed control in organic sweet maize production. Therefore, the objective of this study was to investigate the response of sweet maize to broadcast flaming as influenced by propane dose and crop growth stage. Field experiments were conducted at the Haskell Agricultural Laboratory of the University of Nebraska, Concord, NE in 2008 and 2009 using five propane doses applied at three different growth stages of V2 (2-leaf), V5 (5-leaf) and V7 (7-leaf). The propane doses were 0, 13, 24, 44 and 85 kg ha⁻¹. The response of sweet maize to propane flaming was evaluated in terms of visual crop injury, effects on plant height, yield components (plants m⁻², tillers plant⁻¹, number of ears plant⁻¹, cob length and number of seeds cob⁻¹) and fresh marketable yield. The response of different growth stages of sweet maize to propane doses was described by log-logistic models. Based on most parameters tested, V7 was the most tolerant while V2 was the least tolerant stage for broadcast flaming. The maximum yield reductions with the highest propane dose of 85 kg ha⁻¹ were 22%, 12% and 6% for V2, V5 and V7 stages, respectively. Furthermore, a 5% yield reduction was evident with 23, 25 and 36 kg ha⁻¹ of propane for V2, V5 and V7 growth stages, respectively, suggesting that plants flamed at V7 stage can tolerate higher dose of propane for the same yield reduction compared to the other growth stages. We believe that flaming has a potential to be used effectively in organic sweet maize production if properly used.  相似文献   

Cholinergic interneurons control local circuit activity and cocaine conditioning     

Witten IB  Lin SC  Brodsky M  Prakash R  Diester I  Anikeeva P  Gradinaru V  Ramakrishnan C  Deisseroth K 《Science (New York, N.Y.)》2010,330(6011):1677-1681

Cholinergic neurons are widespread, and pharmacological modulation of acetylcholine receptors affects numerous brain processes, but such modulation entails side effects due to limitations in specificity for receptor type and target cell. As a result, causal roles of cholinergic neurons in circuits have been unclear. We integrated optogenetics, freely moving mammalian behavior, in vivo electrophysiology, and slice physiology to probe the cholinergic interneurons of the nucleus accumbens by direct excitation or inhibition. Despite representing less than 1% of local neurons, these cholinergic cells have dominant control roles, exerting powerful modulation of circuit activity. Furthermore, these neurons could be activated by cocaine, and silencing this drug-induced activity during cocaine exposure (despite the fact that the manipulation of the cholinergic interneurons was not aversive by itself) blocked cocaine conditioning in freely moving mammals.  相似文献   

The effect of urea on refractometric total protein measurement in dogs and cats with azotemia          下载免费PDF全文

Kelsey P. Legendre  Mary Leissinger  Viviana Le Donne  Britton J. Grasperge  Stephen D. Gaunt 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2017,46(1):138-142

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Hydraulic properties and embolism in small-diameter roots of five temperate broad-leaved tree species with contrasting drought tolerance   总被引：1，自引：0，他引：1  

Paul K?cher  Viviana Horna  Ingo Beckmeyer  Christoph Leuschner 《Annals of Forest Science》2012,69(6):693-703

? Context

It has been estimated that about half of a plant??s total hydraulic resistance is located belowground, but it is not well known how temperate tree species differ in root hydraulic properties and how these traits vary with the species?? drought tolerance.

? Aims

We examined root anatomical and hydraulic traits in five broad-leaved tree species with different drought tolerance, analyzed the relation between root anatomy and hydraulic conductivity and root embolism, and investigated the relation of these traits to the species?? drought tolerance.

? Methods

In small-diameter roots (2?C6?mm), we measured vessel diameters and vessel density, specific hydraulic conductivity, and the percental loss of conductivity (??native?? embolism) during summer in a mixed forest.

? Results

Specific conductivity was positively related to vessel diameter but not to vessel density. Drought-tolerant Fraxinus showed the smallest mean vessel diameters and drought-sensitive Fagus the largest. Specific conductivity was highly variable among different similar-sized roots of the same species with a few roots apparently functioning as ??high-conductivity roots??.

? Conclusion

The results show that coexisting tree species can differ largely in root hydraulic traits with more drought-sensitive trees apparently having larger mean vessel diameters in their roots than tolerant species. However, this difference was not related to the observed root conductivity losses due to embolism.  相似文献   

Status of the USA cotton germplasm collection and crop vulnerability     

T. P. Wallace  D. Bowman  B. T. Campbell  P. Chee  O. A. Gutierrez  R. J. Kohel  J. McCarty  G. Myers  R. Percy  F. Robinson  W. Smith  D. M. Stelly  J. M. Stewart  P. Thaxton  M. Ulloa  D. B. Weaver 《Genetic Resources and Crop Evolution》2009,56(4):507-532

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Thermophysiological,haematological, biochemical and behavioural stress responses of sheep transported on road          下载免费PDF全文

M. Pascual‐Alonso  G. C. Miranda‐de la Lama  L. Aguayo‐Ulloa  M. Villarroel  M. Mitchell  G. A. María 《Journal of animal physiology and animal nutrition》2017,101(3):541-551

The study was conducted to evaluate the thermophysiological, haematological, biochemical and behavioural stress responses of sheep transported on road. A total of 44 Chamarita breed adult ewes were randomly allotted to one of two groups, one control group (untransported) and transported group (journey of 4 h), and blood stress indicators were measured 1 day before transport and at four time points post‐transport (0, 4 and 24 h). Thermophysiological profiles of ewes were measured by temperature buttons (iButton Thermochron^®) and placed in intravaginal sponges. Direct observations, with a combination of scan and behaviour sampling, were carried out to collect information on individual behaviour and the time it took the ewes to drink water, eat and rest after returning to their pen respectively. Transported ewes lost approximately 1 kg live weight compared to controls and had higher body temperatures until 12 h post‐transport. Cortisol, glucose, non‐esterified fatty acid (NEFA) concentrations as well as the neutrophil–lymphocyte ratio (N/L) and other physiological indicators were higher immediately after unloading in transported ewes but mostly returned to normal after 4 h, with complete recovery after 24 h. Behavioural analysis post‐transport demonstrated that transported ewes chose to eat before drinking and spent less time resting than controls in the first 3 h after unloading. The study demonstrates that transportation even under short‐journey conditions induced behavioural, physiological and thermophysiological responses indicative of the induction of significant stress, leading to live weight shrinkage that may jeopardize farmer's incomes. Finally, results of this study validated the use of iButton Thermochron^® data loggers for monitoring the stress response during transport.  相似文献