The occurrence of Listeria species and antibodies against listeriolysin-O in naturally infected goats

The occurrence of Listeria spp. in bacteriological samples, and antibodies against listeriolysin-O (ALLO) in sera of those aborted, mastitic and apparently healthy goats were studied. Isolation of the organism was attempted from the samples by selective enrichment in University of Vermont Medium and plating onto Dominguez–Rodriguez isolation agar. Pathogenicity of the isolates was tested by Christie, Atkins, Munch Petersen test, chick embryo inoculation and mice inoculation test. Listeria ivanovii was isolated from 7.5, 5.56 and 14.52% goats of those aborted, mastitic and apparently healthy, respectively. Out of the 120 samples each of feacal, nasal and vaginal swabs 5, 1.67 and 2.5% were positive for L. ivanovii. L. ivanovii was also isolated from 0.83% each of 120 milk and blood samples. L. seeligeri was isolated from 1.67% feacal samples from apparently healthy goats. A total of 120 serum samples were tested by listeriolysin-O (LLO) based indirect ELISA of which 19.16% turned out to be seropositive. The percentage of seropositivity was higher in goats those aborted.