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Summary

Binding of endogenous and exogenous homologous IgG2 and IgM to bovine neutrophils before and after in vitro migration through micropore filters, and in vivo migration through mammary tissues after intramammary injection of endotoxin was evaluated by use of flow cytometry. Immunoglobulin binding to neutrophils at 4 and 37 C was also evaluated. Before and after in vitro migration, neutrophils with endogenously bound IgG2 and IgM averaged 1 and 2% and 23 and 7%, respectively. Before and after in vivo migration, IgG2 and IgM binding averaged 1 and 7% and 26 and 15%, respectively. Before and after in vitro migration, binding of purified IgG2 and IgM averaged 75 and 67% and 8 and 24%, respectively. Before and after in vivo migration, percentage of neutrophils binding purified IgG2 and IgM averaged 92 and 98% and 54 and 70%, respectively. When serum was used as a source of exogenous immunoglobulins, binding of total IgG after in vitro migration increased from 5% to 28% and of IgM from 4% to 20%. After in vivo migration, binding increased from 21% to 47% and from 24% to 56%, respectively. Exogenous binding of IgG2 at 4 and 37 C averaged 75 and 84%, and binding of IgM averaged 8% at either temperature. Endogenous IgG2 was unaffected by temperature; however, binding of IgM decreased from 23% at 4 C to 2% at 37 C. These data indicate that endogenous binding was higher for IgM before migration than after migration, in vitro and in vivo. Furthermore, migration in vivo through cellular matrices induced receptor upregulation for IgG and IgM. Source and concentration of ligand and serum components, other than immunoglobulins, appeared to contribute to receptor expression and availability. Neutrophils that were exposed to endotoxin and migrated into milk expressed more receptors than did unstimulated and nonmigrating neutrophils. The association of IgM with its receptor was temperature-dependent.

Free access
in American Journal of Veterinary Research

SUMMARY

Over periods of 22 and 14 months, IgG antibody concentrations in serum samples obtained monthly from 14 mares and 19 foals, respectively, were measured by use of elisa against antigens of the following environmental microbes: Aspergillus umbrosus, Penicillium brevicompactum, Rhodotorula glutinis, Absidia corymbifera, Aspergillus fumigatus, Humicola grisea, Micropolyspora faeni, and Thermoactinomyces vulgaris. The mares and foals were on pasture from early June until early October, then were stabled during the winter season until the following June. In the mares, increased antibody concentrations against most microbes were observed typically in midwinter and late spring when the horses were stabled; antibody concentrations against R glutinis, however, peaked in August. Concentrations differed between the summer and winter seasons and, in most instances, between 2 consecutive years and correlated with amounts of rainfall during the previous harvest season. In the foals, circulating passively acquired antibodies disappeared within 3 to 4 months after birth. During the first year of life, substantially increased autogenous antibody concentrations were observed only against R glutinis. Antibody concentrations against the other microbes increased gradually toward the end of the indoor season. In a group of foals transferred indoors in autumn, 6 weeks later than the other foals, antibody concentrations were lower when measured in December. Results supported the view that, to minimize exposure to microbial spores during the winter season, horses should be kept outdoors as much as possible and attention should be focused on improving the ventilation in stables and the quality of feeds and beddings.

Free access
in American Journal of Veterinary Research

SUMMARY

Fifty-four neonatal pigs were allotted to 4 groups and reared in an electrically controlled automatic feeding device (autosow). Each group was reared on a different pool of bovine colostrum: fresh, stored 1 month, stored 6 months, and stored 8 years. Bovine and porcine immunoglobulins in the sera of these pigs, and in a group of conventionally reared pigs, were measured periodically during the first 42 days after birth. The maximal concentration of absorbed bovine immunoglobulin was reached between 12 and 18 hours and equaled or exceeded the amount of porcine immunoglobulin absorbed by the conventionally reared pigs. Large differences in the concentrations of the bovine immunoglobulin isotypes among the various pools of colostrum were positively correlated with concentration of these isotypes in the sera of the neonatal pigs fed these pools. Relative to their concentrations in colostrum, approximately 41% of the IgGl, 55% of the IgG2, 29% of the IgM, and 67% of the IgA was absorbed. The IgA was absorbed the best and IgM was least absorbed. Significant trends or differences in absorption were not observed among groups. Neonatal pigs given fresh colostrum, which had a higher fat content, had significantly more weight gain (P < 0.05). This occurred, despite the fact that the fresh colostrum had the lowest concentration of bovine immunoglobulin. Serum half-lives for bovine IgG1 and IgG2 were significantly less than for porcine IgG (P < 0.05), whereas the half-lives for bovine and porcine IgM and IgA were similar.

De novo-synthesized immunoglobulins were detectable in serum after 6 days; IgM concentrations reached a maximum at 15 days in neonatal pigs given stored, but not fresh, colostrum. The IgG and IgA concentrations steadily increased in all groups and were highest on day 42, when the study was terminated. Neonatal pigs ingesting fresh colostrum had significantly lower concentrations of de novo-synthesized IgG and IgA than pigs fed stored colostrum (P < 0.05). Concentrations in these pigs were also lower than those in conventionally reared pigs. This occurred, despite the lower immunoglobulin concentration in fresh colostrum, and correspondingly, the lower amount of bovine immunoglobulin in pigs that received this colostrum and absorbed it into their serum. In most instances, the amounts of immunoglobulin of any isotype absorbed from stored colostrum and the amount of de novo-synthesized immunoglobulin present 6 weeks later, were inversely correlated. Data indicated that a storage-labile, nonimmunoglobulin factor, in bovine colostrum is able to suppress de novo IgG and IgA synthesis by neonatal pigs.

Free access
in American Journal of Veterinary Research

Abstract

Objective—To determine the acute corn-specific serum IgE and IgG, total serum IgE, and clinical responses to SC administration of prophylactic vaccines and aluminum adjuvant in corn-allergic dogs.

Animals—20 allergic and 8 nonallergic dogs.

Procedure—17 corn-allergic dogs were vaccinated. Eight clinically normal dogs also were vaccinated as a control group. Serum corn-specific IgE, corn-specific IgG, and total IgE concentrations were measured in each dog before vaccination and 1 and 3 weeks after vaccination by use of an ELISA. The corn-allergic dogs also had serum immunoglobulin concentrations measured at 8 and 9 weeks after vaccination. Twenty allergic dogs received a SC injection of aluminum adjuvant, and serum immunoglobulin concentrations were measured in each dog 1, 2, 3, 4, and 8 weeks after injection. The allergic dogs were examined during the 8 weeks after aluminum administration for clinical signs of allergic disease.

Results—The allergic dogs had significant increases in serum corn-specific IgE and IgG concentrations 1 and 3 weeks after vaccination but not 8 or 9 weeks after vaccination. Control dogs did not have a significant change in serum immunoglobulin concentrations after vaccination. After injection of aluminum adjuvant, the allergic dogs did not have a significant change in serum immunoglobulin concentrations or clinical signs.

Conclusions and Clinical Relevance—Allergen-specific IgE and IgG concentrations increase after prophylactic vaccination in allergic dogs but not in clinically normal dogs. Prophylactic vaccination of dogs with food allergies may affect results of serologic allergen-specific immunoglobulin testing performed within 8 weeks after vaccination. (Am J Vet Res 2005;66:1572–1577)

Full access
in American Journal of Veterinary Research

calf ingests a sufficient mass of immunoglobulin G (IgG), which is dependent on the volume, and IgG concentration of the colostrum fed; 2 and 2) the efficiency with which this IgG is absorbed which is dependent on the time postpartum at which colostrum

Open access
in Journal of the American Veterinary Medical Association

had been experimentally infected. The purpose of the study reported here was, therefore, to provide additional data to assess the diagnostic use of measuring anti-coronavirus IgG in CSF for the diagnosis of FIP involving the CNS in cats. Special

Full access
in Journal of the American Veterinary Medical Association

Lambs depend on the passive transfer of colostral IgG to provide humoral immunity during the neonatal period, and adequate passive transfer of immunity, determined by measuring serum IgG concentration, is a critical determinant of short

Full access
in Journal of the American Veterinary Medical Association

foals that do not receive adequate amounts of colostral antibodies are at a markedly increased risk for development of an infection, serum or plasma IgG concentrations are routinely measured between 12 and 24 hours of age to determine whether foals have

Full access
in Journal of the American Veterinary Medical Association

because of clinical pessimism or financial constraints. Flow cytometry has been used to diagnose and characterize IMHA in dogs 9–12 and humans. 13–15 This method appears more sensitive than standard agglutination tests for IgG detection. 9–11,13–15 A

Full access
in American Journal of Veterinary Research

discovered in the last century about colostral composition and the physiologic process of absorption from the gastrointestinal tract, relatively little has been done to quantify the effects of different concentrations of IgG1 absorption on subsequent health

Full access
in Journal of the American Veterinary Medical Association