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1.
Innate immunity plays an important role in preventing (barrier function) or combating infection (effector function). An important humoral component of innate immunity is formed by natural antibodies (NAb). The objectives of this study were to determine presence, variation among cows and repeatability within cows over time of total NAb titers directed to the pathogen-associated molecular patterns lipopolysaccharide, lipoteichoic acid (LTA) and peptidoglycan, and titers of NAb directed to the glycoprotein keyhole limpet hemocyanin in milk and plasma of individual cows. Furthermore in milk the antibody isotypes IgG1, IgG2, IgM and IgA binding LTA were analyzed. Ten milk and blood samples were obtained from each of 20 clinically healthy dairy cows from first to seventh parity during a period of 3 weeks. Total NAb binding lipopolysaccharide, LTA, peptidoglycan, and keyhole limpet hemocyanin were detected in milk and plasma, with titers considerably higher in plasma than in milk. Total NAb titers showed significant variation among cows, and repeatability within cows over time (ranging from 0.60 to 0.93). Titers of NAb in milk and plasma were positively correlated (correlation ranging from 0.69 to 0.91). Natural antibodies in milk binding LTA were of all 4 isotypes tested, although IgG2 was on average only present at low titers. All 4 isotypes in milk binding LTA also showed variation among cows, and repeatability within cows over time (ranging from 0.84 to 0.92). We conclude that NAb can be measured in a consistent and repeatable manner in bovine milk and blood plasma.  相似文献   

2.
An immunocompetence profile has been developed for Holstein-Friesian cattle. In vitro and in vivo immunoassays were used to determine (1) the percentage of peripheral blood lymphocyte (PBL) subpopulations bearing surface-membrane receptors for sheep erythrocytes, complement, or surface immunoglobulin; (2) the PBL blastogenic response to leukoagglutinin, concanavalin A, or pokeweed mitogen, (3) the serum immunoglobulin concentrations of IgG, IgM, and IgA, (4) the humoral antibody response to keyhole limpet hemocyanin, and (5) the in vitro blastogenic response and in vivo delayed hypersensitivity skin reaction to purified protein derivative in cattle immunized with BCG.  相似文献   

3.
Oral inoculation of approximately 1.2 x 10(9) viable Escherichia coli to pregnant cows resulted in increased blood serum and colostral whey titers to the "O" antigen. The antibody titers were more pronounced in colostral whey and were correlated with the inoculum strain of Escherichia coli. There was no correlation between antibody titers of the colostrum ingested and the resulting serum antibody titers of the calves. The incidence of diarrhea in calves did not correlate with the antibody titer in the colostrum. The occurrence of diarrhea was significantly greater in calves that did not ingest colostrum until they were 12 hours old, compared with calves that had free access to their dams and suckled within an hour of birth.  相似文献   

4.
Nine pregnant cows were laparotomized and their fetuses were immunized with tetanus toxoid, killed Brucella abortus, and killed Mycobacterium bovis. Blastogenesis assays and total leukocyte and differential counts were done when the calves were 1, 2, 3, 7, 14, 21, 28, and 60 days of age. Initial blastogenesis responses to antigens, phytohemagglutinin, and concanavalin A were not positive as frequently as were the responses obtained when the calves were 2 to 3 weeks of age. The probability of obtaining a positive response to an antigen was positively correlated with the magnitude of the response, as determined by delayed-type hypersensitivity skin reactions. Leukocyte and differential WBC counts in immunized calves were similar to those of unimmunized calves. The mean leukocyte count for the immunized calves remained near 16,000 cells/mm3; blood obtained in the first few days after birth contained a greater number of neutrophils than lymphocytes, whereas lymphocyte-to-neutrophil ratio gradually approached those of adult cattle, in which lymphocytes predominate.  相似文献   

5.
Effects of colostral antibody on susceptibility of calves to Cryptosporidium parvum infection were examined. Six calves were fed pooled colostrum that contained C parvum antibody, 6 times daily (at 4-hour intervals) for 7 days and then milk replacer for 7 days. Colostrum was obtained from healthy cows or cows inoculated parenterally with C parvum oocysts before parturition. Antibody content was determined in serum and colostrum whey, using an ELISA for anticryptosporidia immunoglobulin. Six calves were fed colostrum from healthy cows 1 time, and then milk replacer 6 times daily for 14 days. On day 1, all calves were challenge exposed with C parvum, PO, and were monitored daily for diarrhea and oocyst shedding. Bovine colostrum containing specific antibody to C parvum, at ELISA titers up to 10,240, was not effective in protecting calves against challenge exposure to C parvum.  相似文献   

6.
Holstein calves were used to investigate the effects of immunization procedures against somatostatin (SRIF) on growth and concentrations of somatotropin in plasma. In Trial 1, eight heifers 37 weeks of age were inoculated with cyclic-SRIF conjugated to human alpha-globulin. Final body weight, average daily gain, and measurements of body size were not significantly different between control and SRIF-immunized calves. Apparent total tract nutrient digestibilities and efficiency of feed utilization also were not significantly different between treatments. Plasma concentrations of somatotropin were increased and plasma concentrations of urea nitrogen were decreased in calves immunized against SRIF compared to controls, but these mean differences were not significant. In Trial 2, eleven bull calves seven weeks of age were inoculated with cyclic-SRIF conjugated to keyhole limpet hemocyanin. Calves immunized against SRIF had larger average daily gains (P less than .06) than did control calves. Body size, efficiency of feed utilization, and concentrations of somatotropin in plasma were not significantly different for SRIF immunized calves and control calves. Urea nitrogen in plasma was lower (P less than .04) for calves immunized against somatostatin than for control calves. Data indicate that Holstein calves can produce auto-antibodies against SRIF; however, additional research will be required before such immunization techniques can be effectively used to improve weight gains in cattle.  相似文献   

7.
A 2-yr study was conducted to examine the effects of nutritional restriction of beef cows during the last 90 d of gestation on neonatal immunity and production. Cows were fed corn silage, soybean meal diets; dietary treatments consisted of 1) control (CO), 100% of the NRC (1984) requirements for protein and energy, or 2) restricted (RS), 57% of the NRC requirements for energy and protein. All cows received adequate amounts of this diet postpartum. Each year, 26 Angus cows were grouped by age and weight:height ratio (WT:HT) and allotted randomly to treatments. Calves born to dams within each nutritional treatment group were allotted to one of two colostral treatments: 1) colostrum from their dam, or 2) colostrum from a cow from the other nutritional treatment group. Calves from restricted dams had higher cortisol (33.8 vs 26.1 ng/ml) and lower triiodothyronine (T3) (3.82 vs 4.01 ng/ml) concentrations (P less than .05). Maternal nutrition did not affect either colostrum immunoglobulin G (IgG) concentration (43.0 vs 39.5 mg/ml for RS and CO, respectively) or the calves' serum IgG concentration (19.06 vs 20.17 mg/ml IgG at 24 h for RS and CO, respectively). Yet, calves fed colostrum from restricted cows tended to have lower serum IgG concentration (17.2 vs 22.0 mg/ml IgG at 24 h).  相似文献   

8.
用不同培养基制备的精制破伤风类毒素,加入福氏不完全佐剂免疫豚鼠,测血清中抗体效价。结果表明,加强免疫后,以酪蛋白培养基制备的精制破伤风类毒素,其免疫原性为最强,抗体的效价均值达326IU/ml,与其他各组相比差异显著,这为制备抗原用的培养基的筛选,提供了依据  相似文献   

9.
Concanavalin A (conA) blast proliferation as a quantitative measure of lymphoblast proliferative capacity by blood mononuclear cell supernatants was measured in cattle naturally infected with Mycobacterium paratuberculosis and in healthy control cattle. Blast cell proliferation was significantly reduced in infected animals, compared with control cattle when blood mononuclear cells were stimulated with conA. Proliferation was significantly greater than media control when M bovis purified protein derivative and johnin were used to stimulate cells from the infected group. After sensitizing control and affected cattle with M paratuberculosis bacterin (live M bovis and keyhole limpet hemocyanin in Freund's incomplete adjuvant), infected animals had no difference in blast cell proliferative capacity with the mycobacterial antigens and conA stimulation, whereas healthy animals had significantly increased blast proliferation in response to all the sensitizing antigens. The blast cell proliferative capacity in infected animals with keyhole limpet hemocyanin stimulation was increased significantly after sensitization; however, it remained significantly less than that in the sensitized control group. These data indicate that cattle naturally infected with M paratuberculosis probably produce suboptimal interleukin-2 (IL-2) activity in response to a potent IL-2 inducer (conA) and fail to optimize IL-2 activity when sensitized with a potent immunogen (keyhole limpet hemocyanin).  相似文献   

10.
Immunoglobulin (Ig) G and natural antibody (NAb) IgM are passively transferred to the neonatal calf through bovine colostrum. Maternal IgG provides pathogen- or vaccine-specific protection and comprises about 85% of colostral Ig. NAb-IgM is less abundant but provides broad and nonspecific reactivity, potentially contributing to protection against the dissemination of pathogens in the blood (septicemia) in a calf’s first days of life. In the dairy and beef industries, failure of passive transfer (FPT) of colostral Ig (serum total protein [STP] <5.2 g/dL) is still a common concern. The objectives of this study were to: (1) compare colostral IgG concentrations and NAb-IgM titers between dairy and beef cows; (2) assess the effect of beef breed on colostral IgG; (3) compare passive transfer of colostral Ig in dairy and beef calves; and (4) estimate the heritability of colostral IgG and NAb-IgM. Colostrum was collected from Holstein dairy (n = 282) and crossbred beef (n = 168) cows at the University of Guelph dairy and beef research centers. Colostral IgG was quantified by radial immunodiffusion and NAb-IgM was quantified by an enzyme-linked immunosorbent assay. In dairy (n = 308) and beef (n = 169) calves, STP was estimated by digital refractometry. Beef cows had significantly greater colostral IgG (146.5 ± 9.5 standard error of the mean [SEM] g/L) than dairy cows (92.4 ± 5.2 g/L, P <0.01). Beef cows with a higher proportion of Angus ancestry had significantly lower colostral IgG (125.5 ± 5.8 g/L) than cows grouped as “Other” (142.5 ± 4.9 g/L, P = 0.02). Using the FPT cutoff, 13% of dairy and 16% of beef calves had FPT; still, beef calves had a significantly larger proportion with excellent passive transfer (STP ≥6.2 g/dL, P <0.01). The heritability of colostral IgG was 0.04 (±0.14) in dairy and 0.14 (±0.32) in beef. Colostral NAb-IgM titers in dairy (12.12 ± 0.22, log2 [reciprocal of titer]) and beef cows (12.03 ± 0.19) did not differ significantly (P = 0.71). The range of NAb-IgM titers was 9.18–14.60, equivalent to a 42-fold range in antibody concentration. The heritability of colostral NAb was 0.24 (±0.16) in dairy and 0.11 (±0.19) in beef cows. This study is the first to compare colostral NAb-IgM between dairy and beef cows. Based on the range in NAb-IgM titers and the heritability, selective breeding may improve colostrum quality and protection for neonatal calves in the early days of life.  相似文献   

11.
乳胶凝集试验快速检测副猪嗜血杆菌   总被引:1,自引:0,他引:1  
利用原核表达并经过纯化的副猪嗜血杆菌TbpB N端蛋白及人工合成的特异性多肽制备单克隆抗体,经碳化二亚胺(EDC)将纯化后的单克隆抗体IgG与羧化乳胶共价偶联,并对偶联乳胶的IgG含量及偶联时间等条件进行合理选择,建立了快速检测副猪嗜血杆菌的乳胶凝集试验方法.利用LAT方法检测148株副猪嗜血杆菌疑似菌株,参考16 S rRNA-PCR方法的结果,符合率为83.1%,且致敏乳胶不与临床常见菌株发生凝集反应.结果表明,此检测方法具有操作简便、快速、特异性高的特点,便于在基层推广使用,为副猪嗜血杆菌的诊断和有效防治提供了参考和依据.  相似文献   

12.
The objective of this study was to analyze the influence of colostral quality on serum proteins in calves. Samples were collected from visited farms in Kasetsart University Veterinary Teaching Hospital at Kamphaeng Saen and Nong Pho Animal Hospital. In total, 35 dairy farms contributed 80 dams and calves’ samples. Colostrum samples from 80 dairy cows and blood samples from their calves were taken to evaluate colostral immunoglobulins (Ig) and immunoglobulin G (IgG), and calf serum protein and IgG. Total colostral Ig, colostral and serum IgG, and serum protein were measured by a colostrometer, single radial immunodiffusion, and refractrometer, respectively. Immunoglobulin G and serum protein concentrations increased in the 1st day after birth, and maximum concentrations were seen in the 2nd day and then decreased in the 7th and 14th days. Average?±?SD total colostral IgG concentrations at calving date and at 1 and 2 days after calving were 93.85?±?33.89, 37.11?±?23.51, and 17.23?±?9.4 mg/mL, respectively. The profile of total Ig and IgG concentrations in colostrum had a similar pattern, with the maximum concentrations obtained in calving date and rapidly decreased thereafter. Low IgG concentrations were seen in the 7th and 14th day after calving. The calves that were fed with high quality colostrum had higher serum protein at 1 day of age, 7.49?±?1.01 g/dL, than calves fed with low quality colostrum, 6.40?±?0.86 g/dL (P?<?0.01). The increase in serum protein after first colostrum feeding of high and low quality colostrum was 1.55?±?1.07 and 0.81?±?0.69 g/dL, respectively (P?=?0.02).  相似文献   

13.
OBJECTIVE: To determine whether mammary gland or colostral characteristics at calving could be used to predict colostral immunoglobulin G1 (IgG1) concentration or intramammary infection (IMI) and whether leakage of colostrum affects IgG1 concentration. DESIGN: Prospective study. ANIMALS: 113 multiparous Holstein cows. PROCEDURE: Cows were examined within 3 hours of calving, and mammary gland and colostral characteristics, colostral volume, somatic cell count, and concentrations of IgG1, fat, and protein were determined. Bacteriologic culture of mammary secretions was performed approximately 14 and 7 days before calving and at calving. Associations of gland and colostral characteristics with colostral IgG1 concentration, colostral volume, and IMI were examined. RESULTS: Thick or thin colostrum had higher IgG1 concentration than colostrum of intermediate viscosity. Colostrum from mammary glands that were firm had low IgG1 concentration. Colostral IgG1 concentration was weakly correlated with volume. Intramammary infection was likely to be detected if colostrum contained clots or blood or if the California Mastitis Test (CMT) score was > or = 2. Somatic cell count was higher for glands with IMI than for uninfected glands, and CMT score was correlated with cell count. CLINICAL IMPLICATIONS: Mammary gland and colostral characteristics were of little value in predicting IgG1 concentration. Our findings do not support recommendations that first milking colostrum that is thin (watery) or that is from cows producing large volumes not be fed to dairy calves. Colostral characteristics, particularly CMT score, were of value for predicting IMI.  相似文献   

14.
Antibodies to P. haemolytica were detected in colostral sera of cows and blood sera of calves by means of indirect haemagglutination (IHA) and ELISA. The ELISA titres of the colostral sera of the dams and of the blood sera of the calves showed a significantly positive correlation. There is a positive correlation between the titres of the two serological methods. The results of the challenge infection with P. haemolytica A 1 do not show a correlation between the titres and the severity of the disease. Heifer calves, however, developed more severe pneumonias than calves from older cows.  相似文献   

15.
Dairy cows from five herds were assigned to receive a commercial Pasteurella haemolytica vaccine or no vaccine at all, administered at six and three weeks before parturition. Vaccination was associated with increased leukotoxin neutralizing serum antibody titers in the dams (p < 0.001), and with increased titers in colostrum (p < 0.001). Vaccination of dams also had a significant association with increased passive leukotoxin neutralizing antibody titers in their calves (p < 0.001). Vaccination was also associated with increased indirect agglutinating antibody titers in serum of the dams (p < 0.001). In the analysis of agglutinating antibody titers in colostral whey the interaction "vaccination*herd" was found to be significant (p < 0.001), indicating that the effects of vaccination on colostral titers were not consistent from herd to herd. The analysis was repeated, stratifying by herd. Vaccination was associated with increased agglutinating antibody titers in colostrum (p < 0.05) in three herds of the five in the study. In two of these three herds there were significant increases in passive neonatal titers associated with vaccination. In the remaining herd the mean IgG1 level in the calves was consistent with failure of passive transfer of immunoglobulins (IgG1 < 8.0 g/L). These results suggest that preparturient vaccination of dairy cows can induce modest increases in passive antibody titers to antigens of Pasteurella haemolytica in their calves, but the antigen of interest and the population being studied can affect the outcome.  相似文献   

16.
抗α-INF卵黄抗体的制备与鉴定   总被引:7,自引:0,他引:7  
用人抑制素 ( 1 -2 6 )Tyr.Gly与KLH连接作免疫原 ,免疫本地良种母鸡 ,旨在获得大量抗抑制素卵黄抗体 (eIgY)。实验中 ,收集鸡蛋 ,观察了血清及卵黄中特异性抗体的应答 ,结果经免疫的鸡有免疫应答 ,所产卵的卵黄中可检出大量的有高度活性的抗体。综合运用pH值 ,非球蛋白沉淀法和球蛋白沉淀法 ,制得纯度较高的抗抑制素eIgY。采用阻断ELISA法证实所获得的eIgY具有高度的特异性。用eIgY被动免疫未成年昆明鼠 ,子宫重量明显增加。由此得出结论可以用鸡做生物反应器大量生产抗抑制素抗体 ,用于被动免疫家畜来提高家畜繁殖率  相似文献   

17.
Three pregnant cows were inoculated intramuscularly with inactivated vaccine to bovine rotavirus (BRV) serotype 1 (BRV-1) and serotype 2 (BRV-2). Serum neutralizing antibody (NA) titers against both serotypes increased significantly after immunization. NA titers of colostrum obtained from immunized cows against BRV-1 and BRV-2 were 29286 and 38109, respectively, which were significantly higher than those from non-immunized control cows. Nine and 6 colostrum deprived calves were orally challenged with BRV-1 and BRV-2, respectively, and monitored for clinical manifestation and viral shedding. Five calves of them, 3 with BRV-1 and 2 with BRV-2, received 2 l of milk replacer supplemented with 10% immune colostrum 2 hr before challenge and twice daily for the first 5 days after challenge. Other 10 calves, 6 with BRV-1 and 4 with BRV-2, were fed only milk replacer as controls. All control calves developed severe diarrhea and shed a large amount of BRV in feces, beginning from 24 to 48 hr after challenge inoculation. On the contrary, all calves but one fed colostrum supplement remained clinically healthy after challenge, and BRV was not detected in their feces during feeding immune colostrum. The possibility that continuous feeding of immune colostrum is capable of preventing newborn calves from diarrhea associated with BRV and viral shedding was suggested.  相似文献   

18.
Two experiments were conducted to evaluate two carrier proteins and nine adjuvants in promoting antibody production in heifers immunized against LH. The anti-LH antibody response was evaluated in heifers immunized against LH conjugated to either ovalbumin or keyhole limpet hemocyanin (KLH) (Exp. 1). In Exp. 2, an LH-ovalbumin conjugate was used to evaluate effectiveness of nine different adjuvants in antibody production. Weekly blood samples were collected from all heifers throughout the 23-wk study to determine LH antibody binding activity. In Exp. 1, heifers immunized with the LH-ovalbumin (LH-oval) conjugate had greater LH antibody binding activities (P less than .001) than those immunized with the LH-KLH conjugate. In Exp. 2, nine groups of heifers were immunized with LH-oval suspended in one of nine adjuvants; a 10th group was immunized against ovalbumin alone (control). Only adjuvants that contained at least 40% oil resulted in LH antibody binding activity that differed (P less than .01) from control. These results show that ovalbumin was a superior carrier protein to KLH in enhancing antibody production; adjuvants with greater than 50% oil were superior to those with less oil in promoting LH antibody production.  相似文献   

19.
OBJECTIVE: To determine the effects of moderate feed restriction, single or twin pregnancy, and subclinical pregnancy toxemia (PT) on immune responses of ewes. ANIMALS: 16 Sardinian ewes. PROCEDURE: Six weeks before lambing, ewes were assigned to 1 of 2 groups (n = 8/group) matched for number of fetuses, body condition score, and plasma glucose, non-esterified fatty acids (NEFA), and beta hydroxybutyrate (BHBA) concentrations, and feed intake was restricted for 1 of the groups. Cell-mediated immunity was evaluated in vivo and in vitro. Humoral immunity was evaluated in vivo by determining production of IgG antibodies against keyhole limpet hemocyanin (KLH). RESULTS: Four ewes developed subclinical PT (plasma BHBA concentration > 0.86 mmol/L without any clinical signs of disease). Whether feed was restricted and type of pregnancy (single vs twin) did not have any significant effects on cell-mediated and humoral immune responses. Ewes with subclinical PT had significantly lower in vitro proliferation of phytohemagglutinin-stimulated peripheral blood mononuclear cells and significantly lower values for KLH-specific IgG than did healthy ewes. Plasma BHBA and NEFA concentrations were negatively correlated with in vitro proliferation of peripheral blood mononuclear cells; plasma NEFA concentration was negatively correlated with values for KLH-specific IgG. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that subclinical PT may be associated with impairments in cell-mediated and humoral immune responses in sheep.  相似文献   

20.
New-born calves, artificially fed colostrum or native colostral whey, either dried or preserved by another method, had good health and good weight gains (between 0.05 and 0.60 kg). No greater differences were observed between the groups of calves given three times the colostrum of their mothers, calves given mixed colostrum, and calves fed colostral whey powder. In all groups only individual differences in IgG content in the blood serum were observed after 48 hours from birth. Hypogammaglobulinaemia occurred in individual cases both in calves given small amounts of colostrum or colostral whey and in calves given sufficient quantities. The time that had elapsed from birth to the first drinking did not exert any greater influence upon the IgG level in the blood; the decisive factor was the amount of colostrum taken in by the calf in the first dose. The rate of the absorption of IgG1, IgG2, IgA, and IgM from colostrum and the concentration of the immunoglobulins in the serum depended on the quantity of colostrum in the first dose and were not influenced to any greater degree by the amount of colostrum given to the calves in further doses. The amount of IgG in the blood serum of calves corresponded approximately to the level of colostral antibodies to the virus PI-3. The antibodies to the virus PI-3 and small quantities of IgG were observed also in the serum to new-born calves before drinking colostrum.  相似文献   

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