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1.
To obtain basic information on the state of proinflammatory cytokines in newborn calves, we determined the kinetics of 5 cytokines (IL-1beta, IL-6, TNF-alpha, IFN-gamma and IL-1 receptor antagonist) in sera of newborns during the first 4 weeks of life. At birth, none of the 5 cytokines were detected in almost all serum samples, but the cytokines became detectable within 12 hr after being fed colostram. The mean concentrations of the cytokines reached peak levels by 24 hr and then gradually decreased and became undetectable by 4 weeks after birth. Cytokine mRNA expressions in peripheral blood mononuclear cells of newborns were observed without reference to the cytokine concentrations in sera. Serum cytokines detected in newborn calves are probably colostral origin.  相似文献   

2.
Lactoferrin (LF) is a cationic iron-binding glycoprotein that is abundantly expressed and secreted from glandular epithelial cells and a prominent component of the secondary granules of polymorphonuclear neutrophils. Various in vitro and in vivo experiments demonstrate anti-microbial, -viral, -mycotic and -inflammatory effects of LF, associated with modulations of the immune system. Effects of oral administered LF on selected immune system parameters were studied in calves. Five calves were fed LF beginning on day 3 of life with colostral milk and starting on day 6 of life milk replacer enriched with 0.16% LF was fed. The average daily intake of LF per calf was 1.5-1.6 g/day. Additional five calves served as control group with identical treatment except for the LF supplementation. At the end of the study (day 61 of life), all calves were slaughtered and various tissues were sampled for histological and gene-expression studies. LF given orally was shown to act as an immunomodulatory agent by enhancing the size of Peyer's patches in the ileum and increasing blood serum immunoglobulin G levels. In addition, the number of peripheral blood leucocytes increased and mRNA levels of various interleukins (IL) such as IL-1beta, IL-8, IL-10 and interferon gamma (IFNgamma) in those cells in response to LF treatment were enhanced. In blood, the mRNA expression of the pro-inflammatory marker genes IL-1beta and IFNgamma decreased over 10-week treatment. Additionally, LF feeding decreased villus sizes in the jejunum. Together these findings emphasize the ability of LF to stimulate prominent immune system parameters and that it has the capacity to modulate the immune responses in a positive way.  相似文献   

3.
OBJECTIVE: To determine the amount of colostral IgG required for adequate passive transfer in calves administered colostrum by use of oroesophageal intubation and evaluate the impact of other factors on passive transfer of colostral immunoglobulins in calves. ANIMALS: 120 Holstein bull calves. PROCEDURES: Calves were randomly assigned to specific treatment groups on the basis of volume of colostrum administered and age of calf at administration of colostrum. Colostrum was administered once by oroesophageal intubation. Equal numbers of calves received 1, 2, 3, or 4 L of colostrum, and equal numbers of calves received colostrum at 2, 6, 10, 14, 18, or 22 hours after birth. Serum samples were obtained from calves 48 hours after birth for IgG determination by radial immunodiffusion assay. Effects of factors affecting transfer of colostral immunoglobulins were determined by use of a stepwise multiple regression model and logistic regression models. RESULTS: A minimum of 153 g of colostral IgG was required for optimum colostral transfer of immunoglobulins when calves were fed 3L of colostrum at 2 hours after birth. Substantially larger IgG intakes were required by calves fed colostrum > 2 hours after birth. CONCLUSIONS AND CLINICAL RELEVANCE: Feeding 100 g of colostral IgG by oroesophageal intubation was insufficient for adequate passive transfer of colostral immunoglobulins. At least 150 to 200 g of colostral IgG was required for adequate passive transfer of colostral immunoglobulins. Use of an oroesophageal tube for administration of 3 L of colostrum to calves within 2 hours after birth is recommended.  相似文献   

4.
Experimental, subclinical acidosis was induced by oral administration of sacharose during the last 2 months of pregnancy in 15 cows. Seven cows and their newborn calves were used as a control group. The liver enzyme activities in the serum and the blood acid-base status were determined in the 15 calves from the cows in the experimental group. Mannitol was administered orally to 8 calves from the experimental group to induce osmotic diarrhoea. It was concluded that subclinical acidosis in pregnant cows alters the biochemical liver profile of their newborn calves, affecting the aspartate aminotransferase, alanine transaminase, beta glucuronidase, glutamate dehydrogenase and bilirubin activities in the serum, which are associated with oedematous changes to the hepatocytes. Diarrhoea was accompanied by an increase in the alkaline phosphatase and gammaglutamyl transferase activities and a decrease in the total protein concentration in the serum. These changes were apparently related to the numerous necrotic foci in the liver and the proliferation of the Kuppfer cells. It would appear from these results that the liver damage in the newborn calves was associated with the subclinical, metabolic acidosis in their dams and that osmotic diarrhoea occurring in the neonatal period additionally impaired the liver function.Abbreviations ALP alkaline phosphatase - ALT alanine transaminase - AST aspartate aminotransferase - GR betaglucuronidase - bw body weight - ELISA enzyme-linked immunosorbent assay - GD glutamate dehydrogenase - GGT gammaglutamyl transferase - IU international unit  相似文献   

5.
The objective was to examine whether the administration of colostrum by a drencher is a safe method to achieve satisfying immunoglobulin concentrations in newborn Holstein Friesian (HF)-calves. Twenty-one calves were fed 1 h postnatum with 2 l colostrum from their dam using a nipple bottle (group I); 15 calves were drenched with 4 l colostrum from their dam 1 h postnatum (group II). Thereafter, all calves were fed milk replacer exclusively. Serum concentration of total immunoglobulin [analysed by Sandwich-enzyme-linked immunosorbent assay (ELISA)] 24 h postnatum was higher in drenched calves (25.2 g/l; 12.8/52.2; median and 10/90 percentiles) compared with bottle-fed calves (14.1 g/l; 9.2/24.7). To characterize the kinetics of immunoglobulin absorption, 17 blood samples were taken frequently within 72 h postnatum using a jugular catheter in five calves fed 2 l colostrum by nipple bottle and five calves drenched with 4 l colostrum 1 h postnatum. A slightly delayed increase of serum immunoglobulin concentration (approximately 3 h) was obvious in drenched calves compared with bottle-fed calves, but drenched calves reached significantly higher immunoglobulin concentrations compared with bottle-fed calves. It is concluded that the proper application of colostrum by a drencher is a useful method for adequate colostral supply in newborn calves. The failure of the oesophageal groove reflex in drenched calves caused no clinical consequences.  相似文献   

6.
To investigate the effects of oral administration of an interferon (IFN)-alpha drug on the immune reaction of healthy Japanese Black (JB) calves, peripheral leukocyte populations and their ability to produce cytokine mRNA were analyzed after oral administration of IFN-alpha. Fourteen calves fed in one herd were divided into two groups; seven calves were orally administered 0.1 g/day of IFN-alpha from the day of birth to day 5 on each day (group 1, N=7), and the other seven calves were used as the control (group 2, N=7). Blood samples were collected from the jugular veins of all calves before administration and in weeks 1, 2, 4, 8, and 16 after birth. The number of MHC class II+CD14+ monocytes in the leukocytes population of group 1 increased gradually after birth, and significantly higher numbers were detected in week 4 compared with group 2. MHC class II-CD14+ monocytes in group 1 peaked in week 1, and a significant increase was detected compared with group 2. The level of IL-12 in the cytokine mRNA of group 1 increased gradually between weeks 1 and 2, and a significantly higher level of IL-12 was found compared with group 2. These results suggest that oral administration of IFN-alpha induces activation of the monocyte functions in JB calves.  相似文献   

7.
Transfer of immunoglobulins and survival of newborn calves   总被引：1，自引：0，他引：1  
The survival of 405 newborn calves in a large Central Florida dairy was monitored for a period of 20 weeks. Post-colostral serum samples were obtained from 234 newborn calves 2 to 7 days postpartum and assayed for total serum protein concentration using a refractometer. In the dams, the concentration of colostral immunoglobulins (Ig) at the first postpartum milking was determined by a colostrometer. Season of calving, sex, and breed of the newborn calves were recorded. The likelihood a calf would have satisfactory serum protein (greater than or equal to 5.5 g/dl) given its breed, season of calving, dam's colostral Ig, and dam's calving body condition score were determined using logistic regression analysis. Factors affecting the survival of these calves, up to 20 weeks of age, were studied using the Cox's proportional hazard model. Newborn calves' serum proteins ranged from 3.0 to 8.3 g/dl with a mean of 5.1 g/dl. Calves born to dams with satisfactory colostral Ig (greater than or equal to 50 mg/ml) were unlikely to have satisfactory serum proteins (odds ratio = 0.4) after adjustment for season of calving, parity, breed and dam's body condition score. Calves born from October to January were 3 times more likely to have satisfactory serum proteins compared to calves born during the period of February to July. However, there was no difference in serum proteins between calves born in August and September compared to the ones born in February to July. The survival rate of calves born to dams with satisfactory levels of colostral Ig was poor compared to ones born to dams with low colostral Ig.  相似文献   

8.
The influence of colostral leukocytes on the concentration of immunoglobulins and antibodies against an enterotoxigenic strain of E. coli in the sera of newborn calves was investigated for four weeks using four experimental groups. The calves received either complete colostrum (COL-, n = 16), cell-supplemented milk substitute (MS+, n = 7) or pure milk substitute (MS-, n = 6) during the first three days of life. The cows were not specifically immunized. The sera of the COL+ calves had significantly higher concentrations of antibodies against E. coli mainly of IgG1 specificity on the second day of life as compared to those of the COL-. The sera of the COL+ calves contained significantly more IgM on days 2 and 5 and slightly more IgA during the first week. Both COL groups had equal concentrations of serum IgG. It appears that colostral leukocytes which are an integral part of the colostrum enhance the passive immunity of the neonatal calf, especially in regard of antibodies and immunoglobulin classes which are essential for intestinal immunity. The concentration of IgM in the sera of the MS+ calves was reduced, that of IgG did not rise to appreciable amounts; the IgA synthesis started one week later as compared to the MS- group. The administration of isolated colostral cells led to an impairment of the natural active immunization.  相似文献   

9.
Clinical pharmacokinetics of five oral cephalosporins in calves   总被引：1，自引：0，他引：1  
The minimal inhibitory concentrations (MIC) of cephalexin, cephradine, cefaclor, cefatrizine and cefadroxil for Salmonella species, Escherichia coli and Pasteurella multocida isolated previously from young calves were determined. The MIC90 values for cephalexin, cephradine and cefadroxil ranged between 3.12 micrograms ml-1 and 12.5 micrograms ml-1, whereas those of cefatrizine and cefaclor were 3.12 micrograms ml-1 and 0.78 microgram ml-1, respectively. Each drug was administered intravenously and orally to groups of pre-ruminating calves and orally to early ruminating calves. Although the pharmacokinetic characteristics of the drugs after intravenous injection were similar to other beta-lactam antibiotics, significant differences between the cephalosporins examined were found in respect of certain kinetic parameters. The drugs showed rapid absorption into the systemic circulation after oral administration to pre-ruminating calves but the elimination half-life values (t1/2 beta) varied between three hours (cefaclor and cefadroxil) and nine hours (cefatrizine). The bioavailability of the drugs was about 35 per cent of the administered dose. Co-administration of probenecid with each antibiotic caused a twofold or greater increase in peak serum drug concentrations (Cmax) but the effect on t1/2 beta was variable. Cephalexin, cephradine and cefaclor given to the ruminating calves resulted in very low serum or plasma concentrations and their use should be restricted to younger calves. Cefadroxil was found to give the highest serum concentrations in this age group but had significantly lower bioavailability when compared with the unweaned calves. Provisional oral dosage regimens were computed for each cephalosporin on the basis of the MIC data and the kinetic parameters derived from intravenous and oral drug administration.  相似文献   

10.
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   

11.
Newborn calves were subjected to cold stress and made hypothermic by immersion in water at 15 to 17 degrees C. Cold stress delayed the onset and significantly decreased (P less than 0.05) the rate of absorption of immunoglobulins (IgM, IgG1 and IgG2) up to 15 hours after first feeding of pooled colostrum. However, the net absorption of colostral immunoglobulins was not affected. The possible deleterious effect of cold stress on absorption of colostral immunoglobulins by newborn calves under range conditions is discussed.  相似文献   

12.
Twenty-seven newborn Holstein bull calves were bottle-fed 2 litres of pooled colostrum which had been stored at -20 degrees C. Blood gas analysis before feeding showed a partially compensated respiratory acidosis in most of the calves, although they all appeared to be clinically normal. Mean venous blood pH was 7.346, carbon dioxide tension (PCO2) was 57.5 mmHg (7.6 kPa), bicarbonate was 30.6 mmol/l and base excess was 3.82 mmol/l. Mean serum IgG1 increased to 8.1 g/l after feeding colostrum. Several significant positive correlations were observed between post-absorptive serum protein, IgG1, IgM, gamma-glutamyltransferase (gamma GT) and D-xylose. Calves with either low serum albumin, high serum CK or low serum gamma GT before feeding tended to have less absorption of colostral protein. It was concluded that reduced absorption of IgG1 from colostrum is associated with hypercapnia in apparently healthy newborn calves.  相似文献   

13.
125I-labeled immunoglobulin (Ig)G1 in colostral whey was used to determine the region of maximum absorption of Ig from the small intestine of the neonatal calf and the variation in Ig absorption among calves at the intestinal level. In experiment 1, 5 segments (approx 5%, 35%, 60%, 80%, and 95% of the duodenocecal length) were formed in the small intestine of 9 colostrum-deprived calves shortly after birth. These segments were injected with colostral whey containing 125I-IgG1 4 hours after birth, and uptake, transfer, and absorption (defined as uptake plus transfer) were determined for each segment 2 hours later. Raw data were adjusted for the milligrams of IgG1 injected per gram of intestinal tissue to obtain the least squares mean (LSM) value. The LSM values for absorption of IgG1 from distal segments 3, 4, and 5 were significantly greater (P less than 0.05) than those values for proximal segments 1 and 2. The region of the maximum IgG1 absorption was the lower small intestine, 60% to 80% of the duodenocecal length. There was also an indication of independence between uptake and transfer in each of the segments. Significant differences (P less than 0.05) were present among calves in the LSM values for uptake and absorption, but not for transfer. In experiment 2, thoracic ducts of 8 newborn calves were cannulated 4 to 5 hours after birth. At 6 hours after birth, colostral whey with 125I-IgG1 was injected into an intestinal segment (approx 60% to 80% of the duodenocecal length).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

14.
The role of colostral immunoglobulins for the protection of newborn calves has been studied extensively, but little is known about the importance of colostral leukocytes. To study the uptake of colostral leukocytes in the intestine of calves and to determine preferential sites for this uptake, FITC-labelled colostral cells derived from the respective dams were injected into intestinal loops with/without Peyer's patches of three male Holstein Frisian calves about 5h post natum. In adjacent loops, PBS was injected as control. Loops were excised after an exposure of 1.5-2h. FITC-labelled material and cells were detected by the direct immunoperoxidase method in paraplast sections. Twenty-five consecutive sections were evaluated from each localization. Uptake of labelled material and cells was observed in all three calves in the jejunal Peyer's patch and in two calves in the ileal Peyer's patch as well. In the jejunal Peyer's patch, labelled material and cells were present in epithelium, domes and sinuses around lymphoid follicles, whereas in the ileal Peyer's patch, they were found in the sinuses only. These findings confirm that uptake of colostral leukocytes through the intestinal barrier is possible and that the preferential route of uptake is through follicle-associated epithelium of Peyer's patches.  相似文献   

15.
The influence of colostral leukocytes on lymphocyte counts in the blood of calves and on lymphocyte responses, in particular the Concanavalin A-induced blastogenic response in vitro and the formation of antibodies against sheep erythrocytes, was investigated for four weeks postnatum using four experimental groups. The calves received either complete colostrum (COL+, n = 16), cell-depleted colostrum (COL-, n = 16), colostral cell-supplemented milk substitute (MS+, n = 7) or pure milk substitute (MS-, n = 6) during their first three days of life. In contrast to the calves fed with cell-depleted colostrum (COL-) the calves fed with complete colostrum (COL+) showed no decrease of lymphocyte numbers in the blood on the second day of life, uniform blastogenic responses to two different Concanavalin A concentrations, slightly enhanced antibody formation against sheep erythrocytes and a high spontaneous proliferation of mononuclear cells during the first week of life. In the calves fed with milk-substitute supplemented with colostral cells (MS+) a higher blastogenic response to Concanavalin A and an intensified formation of antibodies against sheep erythrocytes was observed as compared to the MS- calves. A passage of vital colostral lymphocytes through the intestinal wall is postulated. They seem to stimulate and regulate the blastogenic response and enhance the T-helper cell-dependent formation of antibodies against sheep erythrocytes in calves.  相似文献   

16.
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   

17.
Pairs of newborn calves were exposed to bovine leukemia virus (BLV) when they were given their 1st colostrum feeding. Calves that were given 10(6) BLV-infected lymphocytes in colostrum free of BLV-specific antibody became infected. Calves that were fed 10(7), 10(8), or 10(9) infected lymphocytes in colostrum that contained BLV-specific antibody did not become infected. One of 2 calves inoculated intradermally with 250,000 infected lymphocytes was protected by colostral antibody, but the other was not. Colostral antibody titers in the unprotected calf decreased normally until the calf was 4 months old and then increased markedly; this pattern indicates that the presence of colostral antibody may have prolonged the latent period of the BLV infection.  相似文献   

18.

Objective

To evaluate the effect of orally administered cisapride, bethanechol, and erythromycin on the absorption of colostral IgG in dairy calves.

Animals

Twenty‐four healthy neonatal Holstein‐Friesian calves.

Procedures

Calves were randomly assigned to one of the following treatments: 0.9% NaCl solution (2 mL, PO; negative control); erythromycin lactobionate (20 mg/kg BW, PO; anticipated to be a positive control); cisapride (0.5 mg/kg BW, PO); bethanechol chloride (0.5 mg/kg BW, PO). Calves were fed 3 L of pooled bovine colostrum containing acetaminophen (50 mg/kg) by suckling and oroesophageal intubation 30 minutes after each treatment was administered. Jugular venous blood samples were obtained periodically after the start of feeding and plasma total IgG, protein, acetaminophen, and glucose concentrations determined. Abomasal emptying rate was assessed by the time to maximal plasma acetaminophen concentration.

Results

Oral administration of cisapride facilitated the absorption of colostral IgG and protein. The effect of cisapride on abomasal emptying rate could not be evaluated because cisapride appeared to interfere with acetaminophen metabolism. Based on the total IgG and total protein concentration‐time relationships, the beneficial effects of cisapride appeared to occur early after oral administration and were transient.

Conclusions and Clinical Importance

Additional studies appear indicated to characterize the effect of cisapride dose on the magnitude and duration of its effect on facilitating the absorption of colostral IgG and protein. Identification of a nonantimicrobial method for increasing abomasal emptying rate, such as cisapride, will potentially provide a practical and effective method for facilitating transfer of passive immunity in colostrum‐fed dairy calves.  相似文献   

19.
Three main factors underlying the immunity state of newborn calves are evaluated. During the absorption of colostral immunoglobulins the immunoprotein profile of a newborn calf is influenced by the following factors (arranged according to importance): volume of the first colostrum taken in, time of the first drinking, and immunoglobulin concentration (IgG and IgM) in colostrum. When given 1.1 or 2.0 litres of colostrum of about the same quality (as to immunity), the calves of the compared groups had significantly different levels of total serum Ig measured 24 hours after birth: 10.7 and 18.6 U ZST (P less than 0.05) and 48 hours after birth: 11.7 and 19.7 U ZST (P less than 0.01). A significant difference in total serum proteins was observed only in the 48th hour post partum (54.4 and 63.6 g per litre; P less than 0.05). At the intake of 1.5 litres of colostrum within two and five hours after birth, with the same total intake of the sum of IgG and IgM in the groups, the calves exhibited, in the 24th hour, total serum Ig levels of 14.4 and 12.4 U ZST (P greater than 0.05) respectively, and 56.0 and 47.9 g per litre (P greater than 0.05) of total serum protein, respectively. With a different concentration of colostral IgG (122.0 or 77.0 g per litre) the statistically significant Ig absorption into blood was adequately different (17.2 and 10.0 U ZST, respectively, P less than 0.05). The differences in the concentration of total serum Ig and total proteins between the 24th and 48th hour after birth were only very small and statistically insignificant. Regression analysis proved a significant relation (P less than 0.01) between the level of total serum Ig 24 and 48 hours after birth and the total amount of IgG and IgM taken in with the first colostrum. The calves coming from primiparae had a lower immunity (P less than 0.01) in comparison with the calves of multiparae. A similar relation in the absorption of colostral Ig was observed when the spontaneously born calves were compared with those born by the Caesarean section (P less than 0.01).  相似文献   

20.
The effect of postnatal acid-base status on the absorption of colostral immunoglobulins by calves was examined in 2 field studies. In study 1, blood pH at 2 and 4 hours after birth was related to serum IgG1 concentration 12 hours after colostrum feeding (P less than 0.05). Decreased IgG1 absorption from colostrum was associated with respiratory, rather than metabolic, acidosis, because blood PCO2 at 2 and 4 hours after birth was negatively related to IgG1 absorption (P less than 0.05), whereas serum bicarbonate concentration was not significantly related to IgG1 absorption. Acidosis was frequently observed in the 30 calves of study 1. At birth, all calves had venous PCO2 value greater than or equal to 60 mm of Hg, 20 of the calves had blood pH less than 7.20, and 8 of the calves had blood bicarbonate concentration less than 24 mEq/L. Blood pH values were considerably improved by 4 hours after birth; only 7 calves had blood pH values less than 7.20. Calves lacking risk factors for acidosis were examined in study 2, and blood pH values at 4 hours after birth ranged from 7.25 to 7.39. Blood pH was unrelated to IgG1 absorption in the calves of study 2. However, blood PCO2 was again found to be negatively related to colostral IgG1 absorption (P less than 0.005). Results indicate that postnatal respiratory acidosis in calves can adversely affect colostral immunoglobulin absorption, despite adequate colostrum intake early in the absorptive period.  相似文献   

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