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Abstract

Objective—To determine sensitivity and specificity of a cow-side immunoassay kit for assessing IgG concentration in colostrum.

Design—Prospective study.

Animals—76 dairy and 11 beef cows of various parities.

Procedure—Colostrum from first, second, and third milkings and milk samples were collected, and IgG concentration was determined by means of radial immunodiffusion. The immunoassay was performed according to the manufacturer’s instructions, and sensitivity and specificity were calculated by comparing results of the immunoassay (positive vs negative) with results of immunodiffusion (< 50 g/L vs ≥ 50 g/L).

Results—135 colostrum or milk samples were collected. Mean ± SD colostral IgG concentrations, determined by means of radial immunodiffusion for dairy and beef cows were 65.4 ± 51.4 g/L and 114.8 ± 42.7 g/L, respectively. Mean IgG concentrations for first-, second-, and third-milking colostrum samples and for milk samples were 92 ± 49.0 g/L, 74.6 ± 45.1 g/L, 47.5 ± 32 g/L, and 6.8 ± 3.8 g/L, respectively. Sensitivity of the immunoassay (ie, percentage of samples with IgG concentration < 50 g/L with a positive immunoassay result) was 93%, and specificity (ie, percentage of samples with IgG concentration ± 50 g/L with a negative immunoassay result) was 76%.

Conclusions and Clinical Relevance—Results suggested that the immunoassay kit was an acceptable cow-side test to identify colostrum samples with IgG concentrations < 50 g/L. The immunoassay kit should be useful in screening colostrum for adequate IgG concentration before feeding to calves or storage. (J Am Vet Med Assoc 2005;227:129–131)

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To evaluate effects of colostral cells on the ability of neonatal leukocytes to respond in a mixed leukocyte response (MLR) as a means of evaluating specific immune responsiveness.

Animals—10 Holstein calves, their respective dams, and 10 unrelated adult Holstein cows.

Procedure—Soon after birth, their calves were fed maternal whole colostrum or colostrum after cells were removed by centrifugation. Responses for leukocytes obtained from calves during the first 5 weeks after birth, their dams, and unrelated cows were measured by use of 1-way MLR as an indicator of immune development. An internal control treatment, proliferation of lymphocytes stimulated with Staphylococcus enterotoxin B (SEB), was also measured.

Results—Transfer of colostral leukocytes had a significant effect on the MLR and SEB-induced response in calves. Calves receiving whole colostrum had enhanced responses to maternal and unrelated leukocytes 24 hours after ingestion of colostrum. These responses decreased quickly, indicating direct modulation of the neonatal immune response. Calves receiving whole colostrum effectively stimulated the MLR by 24 hours after ingestion of colostrum. In contrast, calves receiving acellular colostrum did not effectively stimulate the MLR until 2 to 3 weeks after birth.

Conclusions and Clinical Relevance—Ingestion of maternal colostral leukocytes immediately after birth stimulates development of the neonatal immune system. These maternal leukocytes enhance development of antigen-presenting capacity as indicated by their ability to stimulate the MLR and SEB response. The influence of ingested maternal cells on neonatal immunity was also indicated by a reduction in reactivity of neonatal cells to maternal alloantigens. (Am J Vet Res 2005;66:1854–1860)

Full access
in American Journal of Veterinary Research

Abstract

Objective

To determine antibody titer against bovine respiratory syncytial virus (BRSV) in dairy calves on farms and to investigate whether passively acquired antibody titers differ in calves born in various seasons.

Sample Population

Serum samples from 129 colostrum-fed replacement calves in 8 dairy herds.

Procedure

A standard ELISA was used to determine BRSV-specific antibodies in serum samples obtained monthly, and antibody titers for calves born in various seasons were compared.

Results

BRSV-specific antibody titer in colostrum-fed dairy calves decreased to undetectable values at 3 to 4 months old. Calves born in winter generally had lower titers, compared with those for calves born in other seasons (P< 0.05). Titers in calves born in seasons other than winter did not differ.

Conclusions and Clinical Relevance

Calves born in winter generally have lower BRSV-specific antibody titers, which may be caused by generally lower antibody titers in colostrum or by factors influencing colostrum intake. (Am J Vet Res 1999;60:1098-1101)

Free access
in American Journal of Veterinary Research

Summary

Failure to obtain passive transfer of immunity via colostrum can be detrimental to the health and survival of a young pup. It has been stated that pups that do not receive colostrum in the first 2 days after birth, be given adult dog serum as a source of protective immunoglobulins. Twenty-five Beagle pups were obtained by cesarean section from 6 Beagle bitches. The pups were allotted to 3 groups at birth. Group 1 was a control group and was allowed to suckle colostrum. Group-2 pups received 22 ml of pooled adult dog serum/kg of body weight (10 ml/lb) sc at birth. Group-3 pups were given 22 ml of pooled adult dog serum/kg by stomach tube at birth. Pups from groups 2 and 3 were separated from the bitch for 48 hours to prevent colostral antibody absorption and were fed a commercially available milk replacer by stomach tube. After 48 hours, all pups were returned to the bitch until they were weaned at 6 weeks of age. Blood samples were collected from all of the pups at birth and on days 1, 2, 7, 14, 21, 28, and 35. The concentration of IgA, IgG, and IgM in serum was determined by radial immunodiffusion and compared by use of a one-way analysis of variance. The control pups had significantly higher serum concentrations of IgA and IgG, than the pups in groups 2 and 3 on days 1 and 2 and 2 and 7, respectively. Group-2 pups had significantly higher serum IgM concentrations on day 1 than either group 1- or group-3 pups.

Free access
in American Journal of Veterinary Research

Summary

A study was conducted to investigate whether aspiration of amniotic fluid is associated with a deleterious effect on absorption of colostral immunoglobulins or on blood gas and acid-base values of healthy newborn calves. Fourteen calves purchased from commercial sources were transported to a research facility immediately after birth and fed colostrum with known concentrations of immunoglobulins. Blood samples for gas analyses were collected within 5 hours of birth, 24 hours later, and prior to euthanasia. Between 3 and 5 days of age, calves were euthanatized by an overdose of barbiturates. Eleven calves had evidence of bronchoaspiration of amniotic fluid, as determined by presence of meconium, squamous epithelium, or keratin in histologic sections of fixed lung or by cytologic analysis of bronchoalveolar lavage fluid. Blood gas tensions and pH were within reference ranges in 11 of 14 calves. Aspiration of amniotic fluid could not be linked to any specific changes in blood gas tensions, add-base status, or absorption of colostral immunoglobulins. Presence of keratin and meconium in the lungs often was accompanied by mild exudative alveolitis and focal atelectasis. It was concluded that aspiration of small amounts of amniotic fluid with or without meconium is common in calves and is not associated with hypoxemia, respiratory acidosis, or failure of passive transfer.

Free access
in American Journal of Veterinary Research
in American Journal of Veterinary Research

Summary

Six foals were deprived of colostrum for the first 36 hours after birth and, instead, received reconstituted powdered milk. Five control foals suckled their dams naturally. Blood samples were obtained from all the foals after birth and at approximately weekly intervals until at least 5.5 months of age. Sera were analyzed for hemolytic complement activity, complement component C3, and correlating IgG concentration. Hemolytic complement (P = 0.0145) and C3 (P = 0.0002) values were significantly higher in colostrum-deprived foals (cdf) than in naturally nursed foals at 2 to 5 days of age. In addition, significantly (P = 0.0149) higher IgG concentration was found in cdf than in naturally nursed foals between 3 and 5.5 months of age. It was concluded that the observed high complement activity in cdf within 2 to 5 days of age may provide an alternative in immune defense for IgG-deprived foals after failure of colostral transfer.

Free access
in American Journal of Veterinary Research

SUMMARY

Immunoglobulin values were determined in fetal and kitten sera. In the fetal and precolostral kitten sera, only IgG was detected, except in 1 case in which IgM was detected. The IgG, IgA, and IgM were transferred to the kittens through colostrum ingestion with some selectivity. Concentration of the transferred IgG, IgA, and IgM decreased significantly with half-lives of 4.15 ± 1.29 days, 2.03 ± 0.33 days, and 2.2 ± 1.2 days, respectively. As a result of this decrease and increase of de novo immunoglobulin synthesis, IgG, IgA, and IgM were at their lowest values when kittens were 20 to 25 days, 14 to 20 days, and 8 to 10 days old, respectively. After their nadir was reached, IgG values increased gradually, IgA slowly, and IgM rapidly, as a result of de novo immunoglobulin synthesis. When the kittens were 90 days old, their immunoglobulin values were 80% (IgG), 7% (IgA), and 100% (IgM), compared with those of adult cats. These findings suggest that kittens that receive inadequate colostrum from their mothers will be particularly susceptible to infection after they are 5 weeks old.

Free access
in American Journal of Veterinary Research

Summary

The infectivity and pathogenic potential of a cell culture-adapted simian rotavirus was evaluated in colostrum-deprived newborn and infant cynomolgus macaques (Macaca fascicularis). Intragastric challenge exposure with the simian rotavirus strain SA11 on postpartum day 2 induced diarrhea in 5 of 5 colostrum-deprived newborn monkeys. Compared with sham-inoculated controls, 3 of the 5 inoculated monkeys also manifested reduced body weight gain during the initial 5 days after challenge exposure. Rotavirus was detected in feces of 3 challenge-exposed monkeys for up to 2 days after inoculation. Evaluation of antibody response after rotavirus inoculation was obscured by high but variable prechallenge-exposure serum titers of rotavirus-specific antibody. Preexisting serum titer of neutralizing antibody in newborn monkeys was not predictive of clinical response to inoculation with rotavirus SA11. Two 90-day-old infant monkeys with low serum neutralizing antibody titer did not have diarrhea, reduced weight gain, or antibody response after oral inoculation with rotavirus SA11. Results of these challenge-exposure studies in newborn cynomolgus monkeys were consistent with a heterologous host-rotavirus model and indicate that neonatal serum antibody of maternal origin may not be associated with resistance to rotavirus-induced disease.

Free access
in American Journal of Veterinary Research

Summary

The effects of alkalinizing agents, administered prior to feeding colostrum, on blood-gas and acid-base values and on absorption of IgGl were determined in 40 newborn Holstein calves. Two treatments, sodium bicarbonate (3 mEq/kg of body weight, IV) and doxapram HCl (2 mg/kg, IV), were evaluated, using a randomized complete-block experimental design. These treatments resulted in significant (P< 0.01) alteration of blood-gas and acid-base values, generally in the direction of normal values for adult cattle. Significant least squares mean effects were detected for sodium bicarbonate treatment on blood pH ( + 0.04 units, P < 0.01), Pco2( + 4.1 mm of Hg, P <0.01), and HCO3 concentration ( + 4.4 mEq/L, P < 0.01). Significant least squares mean effects were detected for doxapram HC1 treatment on blood pH ( + 0.06 pH units, P <0.01) and Pco2(–5.2 mm of Hg, P <0.01). Absorption of colostral IgGl was not affected by the treatments given or by the altered blood-gas and/or acid-base status.

Free access
in American Journal of Veterinary Research