首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 31 毫秒
1.
Reported in this paper are the possible effects of different light regimes on the transformability of lymphocytes in calf blood. The following results were verified against the background of various indices, such as transformation rate, stimulation index, and lymphocyte number, following culturing with the lymphocyte transformation test and morphological evaluation: --The light regimes tested were natural light day, extremely long day with artificial light (24 hours of lighting, 75-100 lx), and divided artificial light day (seven hours light, five hours darkness, seven hours light, five hours darkness, 82-128 lx). The natural and extremely long artificial light days stimulated transformability of lymphocytes in calf blood. --The divided artificial light day tended to depress transformation of calf lymphocytes. Such light-dependent stimulation of lymphocyte transformability is interpreted as an improvement in defence of the animal organism in terms of an unspecific stimulation.  相似文献   

2.
Natural infection of red deer with bovine tuberculosis   总被引：2，自引：2，他引：0  
Six bovine tuberculosis-free red deer hinds were introduced in October 1993 to a 1.8 ha enclosure, within a larger field study site known to contain tuberculous possums, and kept there for 9 months. A Mycobacterium bovis-infected possum was found in the vicinity of the deer enclosure 3 weeks after the introduction. Subsequently, a further eleven infected possums were found in the area. The deer were monitored by repeated composite antibody detection ELISA and lymphocyte transformation assays for tuberculosis, interpreted in parallel, by skin testing and by routine culturing of samples collected from potential excretion sites. Lymphocyte transformation assay evidence of M. bovis infection in four hinds was first observed 4 months after introduction. One other hind became bovine tuberculin lymphocyte transformation assay positive in the 5th month. Positive or equivocal bovine reactivity remained evident at most test episodes. A comparative cervical skin test performed in July 1994, shortly before slaughter, was positive in these five hinds. Mycobacterium bovis was recovered off swabs from the oropharyngeal tonsils of two hinds during routine sampling. Detailed necropsy of the six deer revealed a single typical tuberculous lesion in only one, but culturing of various tissue specimens ascertained that the five blood test and comparative cervical skin test-positive animals were all infected. Mycobacterium bovis was cultured from the oropharyngeal tonsils of four and medial retropharyngeal lymph nodes of two of the deer with no typical gross lesions. Six additional tuberculosis-free hinds were introduced to the enclosure in April 1994 and kept there for 12 months. Four of these animals showed a positive lymphocyte transformation assay response to M. bovis after 9 weeks, but no significant reactivity thereafter. Concurrent observational studies suggest that five of the first six deer probably became infected through close inspection and investigation of the tuberculous possums, although the possibility of deer-to-deer transmission cannot be totally excluded. The likely deer-possum contact, and thus exposure to M. bovis, was related to the curiosity and social ranking of the hinds. The second group appear to have had transient exposure to M. bovis, possibly caused by direct contact with the infected hinds introduced earlier. This group never showed any curiosity toward, or interaction with, possums during the periods of observation.  相似文献   

3.
The function of the immune system was studied in 34 bitches affected by pyometra. The mean age of the animals was 8.1 +/- 2.8 years. Samples of peripheral blood were examined using a battery of immunological tests. Data obtained from four sets of animals, grouped according to the severity of their disease, were compared. Leucocytosis (neutrophilia and partial monocytosis) and lymphopenia were detected in 62 per cent and 35 per cent of the bitches, respectively. The increase in the number of leucocytes was higher in the severely affected bitches. Inhibition of mitogen-driven lymphocyte proliferation was the characteristic feature of the immunological profile in bitches affected by pyometra, and this corresponded with the impairment of the general state of health. Sera from bitches showing functional inhibition of lymphocytes suppressed the activity of lymphocytes isolated from normal dogs. Sera from bitches affected by pyometra also had higher levels of immunoglobulins, lysozyme and circulating immune complexes. It can be concluded that pyometra is associated with an inflammatory response, but also with a marked suppression of immune system activity.  相似文献   

4.
Lambs were used to evaluate the effect of acute heat stress (HS) or restraint and isolation stress (RIS) on endocrinological and immunological functions. In Exp. 1, lambs were exposed to HS (35 degrees C) and control lambs (CN) were exposed to 21 degrees C for 24 h in two replicates (n = 8 lambs total per treatment). Samples of serum were obtained at frequent intervals for evaluation of cortisol; whole blood was obtained for total and differential leukocyte numbers and lymphocyte blastogenic function. The time-trends for cortisol between HS and CN lambs were different following treatment (P less than .005), but neither leukocyte numbers nor lymphocyte blastogenesis in response to mitogens were affected by acute exposure to the elevated ambient temperature. In Exp. 2, lambs (n = 6 per treatment) were given a 6-h RIS treatment and control lambs remained in their home stanchions (CON). Plasma and serum were obtained frequently during treatment and continued until 24 h after the onset of treatment. Plasma was evaluated for adrenocorticotropic hormone (ACTH) and serum was assayed for cortisol. Samples of whole blood also were obtained before and at 6, 12 and 24 h after the onset of treatment for determination of total and differential leukocyte numbers and lymphocyte blastogenic responses to mitogens. Both ACTH and cortisol were elevated in response to RIS; the profiles of these hormones over the 24-h bleeding period differed for RIS and CON lambs (P less than .001).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

5.
Monocytes are important mediators of inflammatory processes and are in the focus of immunological studies. While the preparation of human monocytes is widely established, little is published on the isolation of porcine monocytes for experimental studies. The aim of this study is to establish a cost efficient method of preparing and culturing porcine monocytes of considerable purity and reasonable yield. In our method, we combined and modified different protocols of human monocyte preparation. The blood of a single pig is harvested and treated with EDTA to prevent coagulation. Peripheral blood mononuclear cells are obtained by a density gradient centrifugation using a Bicoll gradient and monocytes are harvested by culturing on serum-treated culture flasks, rinsing and tapping. A high yield is obtained by constant cooling of flasks and tubes. The purity of the culture is evaluated by the expression of CD14, using flow cytometry. Using this method, we reached a purity of 92.6 % (+/? 3.06 %). With this procedure, we established a reliable method to prepare and cultivate porcine monocytes which can be performed cost effectively and does not require special equipment.  相似文献   

6.
An outbreak of bluetongue and the first isolation of the virus in the Sudan are reported. The disease occurred in sheep stressed by walking for five days when biting arthropods were prevalent. Estimates of the morbidity and mortality rates ranged from about 30 per cent and 2 per cent respectively in adult sheep to around 80 per cent and 100 per cent respectively in lambs. The virus was isolated by the inoculation of suckling mice and embryonated eggs with whole blood from febrile sheep. In a gel precipitation test it reacted with specific antiserum to type 10 BT8 strain. No other agent was isolated. Given the relatively mild nature of bluetongue in indigenous sheep, it is believed that the long walking stress coupled with exposure to sunlight might have aggravated the severity of the disease in this particular outbreak.  相似文献   

7.
The concentration of Percoll required for isolating equine peripheral blood mononuclear cells has been reinvestigated. A poor cell yield was obtained at the 60 per cent concentration already reported. It is recommended that workers specifically interested in high yields of mononuclear cells, for investigation of lymphocyte and monocyte functions, use a concentration of 65 per cent Percoll. However, workers wishing to isolate pure populations of equine neutrophils might consider a concentration of 70 per cent in the upper layer of Percoll used to retain the mononuclear cells.  相似文献   

8.
An indirect immunofluorescent test for the rapid detection of infectious bovine rhinotracheitis (IBR) virus in smears of nasal and ocular secretions from infected cattle, was compared with conventional virus isolation procedures using 200 swabs from 107 field outbreaks of suspected IBR. Virus was isolated from 38 per cent of the swabs and the indirect immunofluorescent test detected virus in 14.5 per cent of the positive swabs. Examination of samples from more than one animal increased the confirmation rates of infection during outbreaks to 39 per cent by virus isolation and 21.5 per cent by the immunofluorescent test. Ocular swabs were better than nasal swabs for confirming infection both by virus isolation and immunofluorescence, and agreement between the two tests increased with the number of samples collected during an outbreak.  相似文献   

9.
Pasteurella multocida and P. haemolytica strains contain between 1.5 and three per cent phosphorus, between nine and 14 per cent nitrogen, between two and four per cent DNA, and between five and 18 per cent RNA, the precise figures depending on culturing conditions. High-molecular DNA may be isolated by means of bacteriolysis, using deoxycholate or dodecylsulphate and the usual steps of purification, with yield and purity differing by strains. DNA with sufficient purity can be obtained from Sepharose 2 B by gel chromatography. The isolated DNA yields were characterised, base values being between 37 and 38 per cent GC for P. haemolytica and between 41 and 48 per cent GC for P. multocida. Highly suitable precursors to DNA synthesis for tritium labelling are 3H-thymidine, which is incorporated in excess of 3H-thymine by a factor of 255, as well as 3H-uracil, with its activity being recovered also from the pyrimidine bases of DNA via pyrimidine biosynthesis.  相似文献   

10.
An overview is given about the most common immunological methods for the diagnosis of bovine tuberculosis. These methods are based on cell mediated immune reactions on the one hand (intradermal skin test, interferon-gamma-test, lymphocyte transformation test) or on antibody production against Mycobacterium bovis on the other hand (ELISA). The advantages and disadvantages of the methods as well as their specificity and sensitivity are discussed.  相似文献   

11.
Twelve horses, all of them 10 years old, were vaccinated intramuscularly on 0 and 28 days of the experiment with inactivated vaccine containing only antigens of A-equi-2/Miami/63. Another three unvaccinated horses, each at the age of 10 years, were the negative control group. One, ten-year-old horse was vaccinated with commercial inactivated vaccine containing both antigens of A-equi-2/Miami/63 as well as A-equi-1/Praha/56 as positive control. Three horses were challenged intranasally with homotypic strain of Miami/63, while six other were challenged with heterotypic strains--three with Suffolk/89 and three with Kentucky/86. Three horses vaccinated with vaccine containing only strain A-equi-2/Miami/63 were not challenged. In the group of three unvaccinated horses, each one was challenged intranasally with different strains studied in this experiment. The horse vaccinated with commercial vaccine was not challenged. Replication of each strain was done in chick embryos. During the experiment blood from horses was collected for hematological and immunological examinations (antigen-specific and antigen-nonspecific lymphocyte transformation tests, lymphocyte immunophenotyping, antigen-specific leukocyte migration inhibition test and hemagglutination inhibition test). The statistical analysis showed that the dynamics of lymphocyte immunological reactivity in horses vaccinated with inactivated vaccine containing antigens of A-equi-2/Miami/63 in response to further antigen stimulation (in vitro) was different comparing the homotypic or nearly homotypic challenging with Miami/63 and Suffolk/89 respectively, to the more heterotypic one with the strain Kentucky/86. In horses challenged with classical homotypic strain of Miami/63 no clinical signs were observed. These results confirm that the vaccine shall consist of the strains currently circulating in the horse population.  相似文献   

12.
This experiment was performed utilizing a total of 21 primiparous crossbred sows to determine whether a state of immunological suppression occurs during the latter stages of pregnancy in the pig and whether dichlorvos treatment affects immunological function of sows. Immunological reactivity was monitored by the use of in vitro lymphocyte transformation experiments employing the mitogens phytohemagglutinin (PHA), concanavalin A (Con A), pokeweed mitogen (PWM) and lipopolysaccharide (LPS). The degree of blastogenesis of lymphocytes recovered from animals on this experiment was not affected by dichlorvos treatment. Blastogenesis was not affected by stage of pregnancy except in the case of that induced by LPS, which decreased (P less than .05) with advancing pregnancy. Sera from animals in this experiment were tested in a PHA-induced lymphocyte transformation experiment and it was found that sera from control animals were not inhibitory at any time. On the other hand, sera from dichlorvos-treated sows inhibited (P less than .01) PHA-induced blastogenesis. The possibility exists that dichlorvos may increase fetal survival by inhibiting the ability of the sow to immunologically damage the fetus.  相似文献   

13.
Two culturing recipes were suggested for Pasteurella multocida and Pasteurella haemolytica, one partialy defined nutritive defined nutritive medium with 0.5 per cent yeast extract and one chemically defined medium. Both had been composed on the basis of studies into nutrient demand and into the effects of complex nutritive substrates. Both nutritive media are applicable also to culturing other bacterial species. (Among the strains tested so far were streptococci, staphylococci, Escherichia coli, pseudomonas, protest, Salmonella,, Shigella, and Haemophilus.)  相似文献   

14.
A whole blood lymphocyte transformation test was used to examine cattle with varying degrees of infection with Mycobacterium paratuberculosis. Minimally infected animals characteristically responded to johnin purified protein derivative in the lymphocyte transformation test but did not routinely react on serological and/or skin testing. Heavily infected animals showed considerable variation in their lymphocyte transformation responses to antigen and some of them were consistently unresponsive. Antigen induced lymphocyte transformation reactions were recorded in 7.6 to 41.5% of uninfected animals whose infection status was determined by bacteriology and/or histopathology. The number of positive reactions recorded in uninfected animals depended on the population, the larger percentage being found in a herd with a proven history of paratuberculosis. The potential of lymphocyte transformation as a diagnostic test for bovine paratuberculosis is discussed.  相似文献   

15.
A monoclonal blocking enzyme-linked immunosorbent assay (ELISA) and an indirect haemagglutination assay (IHA) were applied to serum samples from 124 specific pathogen-free (SPF) breeding and multiplying herds, which participate in the routine serological surveillance of the Danish SPF programme. Clinical and pathological observations of the herds and microbiological culturing of Mycoplasma hyopneumoniae were used to calculate herd sensitivity, herd specificity and herd predictive values for the two serological assays. The ELISA was superior to the IHA in herd sensitivity and herd specificity, with values of 93 per cent and 96 per cent, respectively, for the ELISA, and 61 per cent and 92 per cent for the IHA. During the six month period of evaluation 2.5 per cent of the herds were infected with M hyopneumoniae each month. At this level the IHA was found to have a positive herd predictive value of 16 per cent, compared with 39 per cent for the ELISA. The negative herd-predictive value on the same level was 99.8 per cent for the ELISA and 98.9 per cent for the IHA. If the assays were applied to a group of herds with a herd prevalence of M hyopneumoniae infection of 30 per cent (as is the case with the production herds in the Danish SPF programme) the predictive value of a positive herd diagnosis would be 91 per cent for the ELISA and 76 per cent for the IHA, and the predictive value of a negative herd diagnosis would be 97 per cent with the ELISA and 85 per cent with the IHA.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

16.
A method for examining lymphocyte blastogenesis in whole blood cultures of neonatal calves is presented. Considerable variation in magnitude of thymidine incorporation was noted between animals but the general trend of response was uniform. Maximum responses occurred at different culture times for each mitogen. In a standard 0.2 ml micro culture system using 10,000 mononuclear cells per culture incubated for 96 hours in 5 per cent fetal bovine serum maximum mitogenic responses were obtained with 0.8 microgram phytohaemagglutinin per culture, 1 microgram concanavalin A per culture and 0.08 microgram pokeweed mitogen per culture.  相似文献   

17.
The relationship between the optimum concentration of mitogen which induces lymphocyte blastogenic response and the receptor occupancy by mitogen was investigated. The receptor occupancies which induced maximal blastogenic activity in equine, bovine and canine peripheral blood lymphocytes (PBL) were 31.1 per cent, 26.5 per cent and 38.4 per cent with phytohaemagglutinin-P, and 48.2 per cent, 17.9 per cent and 24.5 per cent with concanavalin A, respectively. The data clearly show that each animal species had its own optimum concentration of mitogen for stimulation of PBL. Optimum concentration for blastogenesis and number of binding sites of each mitogen had a good correlation with each other for all three species.  相似文献   

18.
The slide agglutination test for the diagnosis of filariasis in camels   总被引：1，自引：0，他引：1  
The slide agglutination test was adapted for the diagnosis of filariasis in camels, using an antigen prepared from the microfilariae by a simple lytic technique. The preliminary results were satisfactory as the test detected 86 per cent of the infected animals. Only 6 per cent of the healthy camels with no blood parasites or microfilariae in their blood gave positive results and no positive reactions were obtained from 18 animals suffering from Trypanosoma infection.  相似文献   

19.
The SNAP Foal IgG test (IDEXX) as evaluated for its accuracy and usefulness by measuring blood samples collected from 42 foals between 24 and 48 hours after birth. The results were compared with the single radial immunodiffusion (SRID) test as the reference method. The SNAP test was quick and easy to perform, and the results were similar to those obtained by SRID in 64 per cent of the samples. The best results were found with low (< 400 mg/dl) and high (> 800 mg/dl) concentrations of immunoglobulin G, with an accuracy of 80 per cent and 89 per cent, respectively. The intermediate concentrations were usually lower when measured by the SNAP test than by the SRID test, possibly owing to the variable volume of blood added to the test with the sample loop.  相似文献   

20.
The recovery of Sporothrix schenckii from blood samples is rare, and the diagnosis of systemic sporotrichosis is usually made at necropsy. In this report, S schenckii was isolated from two or more internal organs of nine necropsied cats with naturally acquired sporotrichosis. Haematogenous spread was demonstrated in vivo by the isolation of S schenckii from the peripheral blood of 17 (n = 49, 34.4 per cent) cats. Feline leukaemia virus (FeLV) was not detected, and co-infection with feline immunodeficiency virus (FIV), observed in nine cases (n = 43, 20.9 per cent), apparently did not affect the isolation of S schenckii from peripheral blood or from the internal organs.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号