Bovine Viral Diarrhea Virus in Swine: Characteristics of Virus Recovered from Naturally and Experimentally Infected Swine          下载免费PDF全文

A. L. Fernelius  W. C. Amtower  G. Lambert  A. W. McClurkin    P. J. Matthews 《Canadian journal of veterinary research》1973,37(1):13-20

A noncytopathogenic field strain of bovine viral diarrhea virus (BVDV) was isolated from an Iowa farm brood sow and from her hysterectomy-derived, colostrum-deprived (HDCD) piglets. This field isolant was fully virulent for a neonatal calf. The NADL strain of BVDV was passaged through a series of HDCD piglets with no resultant loss of virulence for neonatal calves. Most of the BVD viral isolants recovered from pigs had been changed from a cytopathogenic biotype to a noncytopathogenic biotype. Circumstantial evidence points to swine as “carrier” hosts of BVDV.  相似文献   

Prédiction de l''ovulation chez le bovin par dosage rapide de la LH plasmatique et observation de l''ovulation par laparoscopie.          下载免费PDF全文

C Bernard  J P Valet  R Béland    R D Lambert 《Canadian journal of veterinary research》1984,48(1):97-101

The last hours of intrafollicular maturation are important to preserve the potential of oocytes for fertilization and development. To collect mature oocytes it is consequently essential to predict accurately the time of ovulation. Therefore we have modified a regular and specific plasma LH radioimmunoassay to a convenient assay providing reliable results within four to five hours. Using this technique we have been able to detect the LH peak with a delay small enough to predict the moment of ovulation; then we have been able to observe and photograph ovulation. The antigen-antibody reaction takes place during a two hour incubation at 37 degrees C. The immune complex is precipitated by addition of a rabbit anti-gamma-globulin and incubation at 22 degrees C for 30 minutes. The variation between fast and regular assays is lower than 15%. From a study of 25 cycles in 12 animals we suggest intervals of approximately 27 hours between the beginning of the LH peak and ovulation and of about 17 hours between the end of the peak and ovulation. Intervals between the beginning of heat and ovulation appear irregular and cannot be used with certainty as a reference point to predict ovulation. Five ovulations were observed closely and in the five cases, the formation of an apex was noted Our results clearly show that with the technique mentioned above we can predict rapidly and precisely bovine ovulation.  相似文献   

Detection of rotavirus in faecal specimens with a monoclonal antibody enzyme-linked immunosorbent assay: Comparison with polyclonal antibody enzyme immuno-assays and a latex agglutination test     

M Sneyers  C Thiriart  C Buryns  A.-F Lambert  C Collignon  A Schwers  P Coppe  H Antoine  J.D Franssen  J Urbain  L Karelle-Bui  P.-P Pastoret 《Comparative immunology, microbiology and infectious diseases》1989,12(4):95-104

Monoclonal antibodies have been produced against the 81/36F strain of rotavirus. One of them, was chosen as diagnostic reagent: it showed high ELISA reactivity with all the bovine, human and porcine rotavirus strains tested and reacted with VP6, structural protein product known to support the common rotavirus antigen.

A sandwich ELISA procedure using the chosen monoclonal as “capture and detecting” antibody was performed to detect rotavirus in faecal samples from experimentally inoculated newborn calves: it always gave a negative response with meconium and a positive response for the stool specimens which rotavirus have been isolated. This assay was compared with Enzygnost and Slidex Rota Kit tests and with a non-commercial sandwich ELISA test using polyclonal antibodies: it showed more sensitivity than the agglutination test and was as sensitive as the other two tests to detect rotavirus in routine diagnostic material. The test evaluated showed no equivocal results.  相似文献   

Histopathological studies of the heart in three lines of broiler chickens     

M. Gesek  I. Otrocka-DomagaŁa  R. SokóŁ  K. PaŹdzior-Czapula  B. D. Lambert  A. M. WiŚniewska 《British poultry science》2016,57(2):219-226

1. The aim of this study was to analyse the morphological lesion pattern of the heart of broiler chickens (Cobb 500, Hubbard F15 and Ross 308) during fattening with no clinical signs of disease and to determine the most susceptible period for the occurrence of morphological lesions.

2. The most frequently diagnosed lesions in each genetic line were degeneration of the fibres with vacuolation, congestion of cardiac muscle, oedema and vacuolisation of the Purkinje cells.

3. The highest numbers of morphological lesions were observed on d 38, 31 and 10 of life. The lesions were most numerous in the septum, followed by the left and right ventricles.

4. Ischaemic cardiomyocytes were also most numerous on d 38 of life and in the left ventricle.

5. Overload of cardiac muscle, prolonged hypoxia and increasing body weight on d 38 are the likely reasons for the largest number of lesions and ischaemic fibres, which may lead to heart failure.

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Benzothiadiazole‐primed defence responses and enhanced differential expression of defence genes in Vitis vinifera infected with biotrophic pathogens Erysiphe necator and Plasmopara viticola     

M. C. Dufour  C. Lambert  J. Bouscaut  J. M. Mérillon  M. F. Corio‐Costet 《Plant pathology》2013,62(2):370-382

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Effects of soil fumigation with Telone-C on the field inoculum potential of tobacco rattle virus and potato yields     

C. H. Livingston  R. Lambert  M. Kaufmann  K. Knutson 《American Journal of Potato Research》1976,53(3):81-86

Two Julesburg sandy-loam fields in Weld County, Colorado, with a history of Corky Ringspot (CRS) caused by tobacco rattle virus (TRV) were injected with Telone-C as fall or spring applications and planted to potatoes. Deep soil sample cores taken from the experimental fields were planted toNicotiana tabacum L. var. Samsun serving as TRV bait and indicator plants. Systemic infection of bait plants and assay of the bait plant roots for TRV indicate that potential TRV inoculum was present which escaped the effects of fumigation treatments. TRV was found to be widely but erratically distributed throughout the experimental fields. The low incidence of CRS in tubers harvested from the treated fields suggests that fumigation may have short term benefits but potential inoculum exists which could lead to infection after the effects of fumigation have dissipated. The total yield of tubers was increased in the two cultivars planted (Norgold and Norland) in the fumigated fields receiving spring or fall applications. The yield of U.S. No 1 Grade potatoes in the Norland cultivar was increased significantly by both fall and spring fumigation. These yield increases were directly related to the reduced incidence ofVerticillium wilt observed in the fumigated soils and reported as a personal communication from unpublished data.  相似文献   

Colonization and survival capacities underlying the multifaceted life of Rhodococcus sp. PBTS1 and PBTS2     

Danny Vereecke  Elizabeth J. Fichtner  Paul Q. Lambert  Peter Cooke  James Kilcrease  Rio A. Stamler  Yucheng Zhang  Isolde M. Francis  Jennifer J. Randall 《Plant pathology》2021,70(3):567-583

Little is known about the epidemiology of the newly emerged disease on pistachio rootstock designated pistachio bushy top syndrome (PBTS). Here, we analysed the survival and colonization capacities of the two causative agents, Rhodococcus corynebacterioides-like PBTS1 and R. fascians PBTS2, in the different habitats they occupy. Additionally, we examined their chromosomal sequences for genes that would support their ecology and provide experimental evidence for some of their predicted functions. We demonstrate that the soil competence of PBTS2 is better than that of PBTS1 and that both bacteria behave chemotactically, allowing them to translocate from soil to the rhizoplane. Once on the rhizoplane and the phylloplane, the PBTS bacteria form extensive epiphytic biofilms, probably aided by exopolysaccharide production. From these biofilms, the bacteria colonize the plant's interior tissues through the formation of ingression sites, likely created by the localized activity of cell wall-degrading enzymes. The observed systemic spreading of the PBTS strains throughout the plant tissues is probably mediated by surface motility and agrees with the occurrence of symptoms in both the aerial and root parts of the plant host. Based on all available information, we provide a working model on this pathosystem to be used as a conceptual framework for future research.  相似文献   

Comparison of In Vitro Developmental Competence of Cloned Caprine Embryos Using Donor Karyoplasts from Adult Bone Marrow Mesenchymal Stem Cells vs Ear Fibroblast Cells     

PJ Kwong  HY Nam  WE Wan Khadijah  T Kamarul  RB Abdullah 《Reproduction in domestic animals》2014,49(2):249-253

The aim of this study was to produce cloned caprine embryos using either caprine bone marrow‐derived mesenchymal stem cells (MSCs) or ear fibroblast cells (EFCs) as donor karyoplasts. Caprine MSCs were isolated from male Boer goats of an average age of 1.5 years. To determine the pluripotency of MSCs, the cells were induced to differentiate into osteocytes, chondrocytes and adipocytes. Subsequently, MSCs were characterized through cell surface antigen profiles using specific markers, prior to their use as donor karyoplasts for nuclear transfer. No significant difference (p > 0.05) in fusion rates was observed between MSCs (87.7%) and EFCs (91.3%) used as donor karyoplasts. The cleavage rate of cloned embryos derived with MSCs (87.0%) was similar (p > 0.05) to those cloned using EFCs (84.4%). However, the in vitro development of MSCs‐derived cloned embryos (25.3%) to the blastocyst stage was significantly higher (p < 0.05) than those derived with EFCs (20.6%). In conclusion, MSCs could be reprogrammed by caprine oocytes, and production of cloned caprine embryos with MSCs improved their in vitro developmental competence, but not in their fusion and cleavage rate as compared to cloning using somatic cells such as EFCs.  相似文献   

Chemical form of dietary l‐Carnitine affects plasma but not tissue Carnitine concentrations in male Sprague–Dawley rats     

B. D. Lambert  C. M. Dobson  N. M. Cherry  M. G. Sanderford 《Journal of animal physiology and animal nutrition》2009,93(2):174-180

In Experiment 1, rats (n = 54) were randomly assigned to control or one of the four sources of l ‐Carnitine supplemented at either 100 or 200 μmol/kg/day and were allowed to acclimate for 14 days. Following a 12‐h fast, plasma samples were obtained at 0, 5, 10, 15, 30, 60, 120, 240, 480 and 720 min after l ‐Carnitine feeding and assayed for free l ‐Carnitine concentration. Plasma‐free l ‐Carnitine levels were affected by time after treatment intake (p < 0.0001) and l ‐Carnitine source (p < 0.0001). The time × source interaction was not statistically significant (p = 0.99). In Experiment 2, rats (n = 54) were randomly assigned to control or one of the four sources of l ‐Carnitine at either 100 or 200 μmol/kg/day and were acclimated as in experiment 1. Rats were sacrificed 120 min after feeding. Samples of liver and skeletal muscle were obtained and assayed for free l ‐Carnitine concentration. Neither skeletal muscle (p = 0.44) or liver (p = 0.59) tissue concentrations of l ‐Carnitine were affected by any l ‐Carnitine source as compared with the control. We conclude that some differences exist in plasma concentrations of free l ‐Carnitine following ingestion of different chemical forms of l ‐Carnitine. It is unclear if these differences in the circulating concentration of free l ‐Carnitine translate into any physiological differences for the animal. In this study, chemical form of l ‐Carnitine had no effect on skeletal muscle or liver tissue concentrations of l ‐Carnitine in young male Wistar rats.  相似文献   

Cellular model for induction of drip loss in meat   总被引：5，自引：0，他引：5  

Lambert IH  Nielsen JH  Andersen HJ  Ørtenblad N 《Journal of agricultural and food chemistry》2001,49(10):4876-4883

Drip loss from porcine muscle (M. longissimus dorsi) contained high concentrations of K(+) ( approximately 135 mM) and organic osmolytes, for example, taurine ( approximately 15 mM), as well as significant amounts of protein ( approximately 125 mg.mL(-1)). Thus, the drip reflects release of intramuscular components. To simulate events taking place at the time of slaughter and leading to release of osmolytes and subsequent formation of drip loss, C2C12 myotubes were exposed to anoxia and reduction in pH (from 7.4 to 6.0). Anoxia and acidification increased the cellular Ca(2+) concentration ([Ca(2+)](i)) at a rate of 22-32 nM.min(-)(1). The anoxia-induced increase in [Ca(2+)](i) was mainly due to influx via sarcolemmal Na(+) channels. As mammalian cells swell and release lysophospholipids during anoxia, C2C12 cells and primary porcine muscle cells were exposed to either hypotonic shock or lysophosphatidylcholine (LPC) and the release of taurine was followed. The swelling-induced taurine efflux was blocked in the presence of the anion channel blocker (DIDS), the 5-lipooxygenase inhibitors (ETH 615-139 and NDGA) but unaffected by the presence of vitamin E. In contrast, the LPC-induced taurine release was unaffected by DIDS but abolished by antioxidants (butylated hydroxytoluene and vitamin E). Thus, stress-induced taurine release from muscles may precede by two different mechanisms, one being 5-lipooxygenase dependent and the other involving generation of reactive oxygen species. A model for the cellular events, preceding formation of drip in meat, is presented.  相似文献