Humoral antibody responses to experimental and spontaneous Salmonella infections in cattle measured by ELISA

Abstract

Summary The humoral IgM and IgG antibody responses to experimental and spontaneous Salmonella infections were followed by ELISA in calves and dairy cattle. Calves orally inoculated with S. dublin SVA47 (O 9, 12) or S. typhimurium SVA44 (O 4, 5, 12) developed fever and diarrhoea. The organisms were excreted almost daily for 12 and 19 days, respectively, and intermittently thereafter. The infected calves responded with significantly (p < 0.05) elevated IgM and IgG antibody titres after about 10–15 days. The increases in antibody titres against S. typhimurium SVA 44 were demonstrated earlier than those against S. dublin SVA 47. A field study of spontaneously S. dublin infected herds, herds with prior Salmonella infection and herds without any detectable, persistent or prior Salmonella infection, demonstrated that the number of ELISA positive sera was significantly higher both in infected herds and in herds with prior Salmonella infection than in the non‐infected control herds during almost the whole twelve‐month period of the study. After the herds were declared free from Salmonella on the basis of bacteriological examinations of faecal specimans, increases in both IgM and IgG titres were recorded, indicating persistence of the infection. Zusammenfassung ELISA‐Test zur Bestimmung humoraler Antikörperbildung bei spontaner und experimentell hervorgerufener Salmonellainfektion des Rindes Die humorale IgM und IgG Antikörperbildung bei spontaner und experimentell hervorgerufener Salmonellainfektion von Kälbern und Milchkühen wurde mit dem ELISA geprüft. Die Kälber wurden per oral mit dem Salmonellastamm S. dublin SVA 47 (O 9, 12) oder S. typhimurium SVA 44 (O 4, 5, 12) infiziert und erkrankten an Fieber und Diarrhoe. Salmonellabakterien wurden in den Kotproben an den ersten 12 bzw. 19 Tagen täglich und danach intermittierend nachgewiesen. Die infizierten Kälber hatten nach 10–15 Tagen einen signifikanten (p < 0,05) IgM‐ und IgG‐Titer. Der Titeranstieg gegen die Salmonella typhimurium‐Infektion (SVA 44) war schneller nachweisbar als derjenige gegen die Salmonella dublin‐Infektion (SVA 47). In Rinderbeständen mit spontaner Salmonella dublin‐Infektion und in Beständen, in denen früher Salmonellainfektionen aufgetreten waren, wurde eine signifikant höhere Anzahl ELISA‐positiver Seren nachgewiesen als in Beständen ohne Salmonellabefall. Nachdem die Rinderbestände aufgrund bakteriologischer Faecesuntersuchungen als “Salmonella‐frei” erklärt wurden, konnten Titeranstiege bei den IgM‐ und IgG‐Antikörpern festgestellt werden was beweist, daß sich noch latent infizierte Tiere in den Beständen befinden. Résumé Test ELISA pour la détermination de la formation d'anticorps lors d'infection à Salmonella spontanée et expérimentale chez le bovin La formation d'anticorps humoraux IgM et IgG lors d'infections spontanées et expérimentales à Salmonella chez des veaux et des vaches laitières a été testée au moyen de l'ELISA. Les veaux furent infectés par voie orale avec la souche S. dublin (O 9, 12) ou S. typhi murium SVA 44 (O 4, 5, 12) et p...

Salmonella in Dairy Cattle

“…In this way, one can measure the humoral immune response as an indicator of current or previous infection. 36,37 Some laboratories report the ELISA result as a semiquantitative percentage value, giving an optical density reading referable to a standard set of controls. In addition, ELISA tests can also be used for individual or bulk tank milk sample screening, 38 and have come to be used quite extensively in countries such as Denmark, where active surveillance programs for this serovar are in effect.…”

Risk Factors and Control Measures for Bacterial Contamination in the Bovine Meat Chain: A Review on Salmonella and Pathogenic E.coli

“…As an alternative to the cultural methods, serological methods that consist in the detection of antibodies specifically directed against some antigens expressed by the pathogen exist. An example is the measurement of immunoglobulins directed against O-antigens from Salmonella Dublin in the blood that was reported to be used as an indicator of Salmonella infection in cattle (Robertsson, 1984). However, further studies indicate that serological tests are indicative on the current and/or previous infection status of the subjects but not on their shedding status (Olopoenia & King, 2000).…”

Within-herd prevalence ofSalmonellaDublin in endemically infected dairy herds

“…The correlation between seroprevalence and faecal culture-positive prevalence within each age group and across all age groups was investigated using Spearman's correlation. Furthermore, the correlation between the faecal culture-positive prevalences at one visit and the seroprevalences at the next visit for each age group and across all age groups were investigated using Spearman's correlation, because it could be expected that the increase in seroprevalence would be delayed by at least 2-4 weeks compared to the point in time of the shedding of the bacteria [17][18][19]. Factors affecting seroprevalence at each herd visit were investigated for each of the age groups using three hierarchical mixed models with seroprevalence as the outcome and season and bacteriological status of the age group on the given visit date as potential risk factors in the model.…”