ABSTRACT
The present study was conducted on 80 pregnant buffalo dams and their neonates, of which 20 pregnant dam were injected s/c two times, at 8 weeks before the expected time of calving and again 4 weeks later with tetravalent vaccine [Lactovac vet.] to control neonatal calf diarrhea. The rest of dams were used as a control group. Immunoglobulin [IgM and IgA] concentration levels and some biochemical parameters [total protein, albumin and globulin] were measured in serum of buffalo dams prior to vaccination and after calving and compared with those of non vaccinated dams. The means of serum immunoglobulins and [total protein, albumin and globulin] of vaccinated dams after calving were increased when compared to those of control non vaccinated dams after calving. A high significant difference was noticed between serum IgM of vaccinated and non vaccinated dams after calving. High significant differences were observed between 36-48 h old calves of both groups with regard to serum IgG, IgM and IgA. High significant differences were observed between colostral IgG, IgM and IgA of vaccinated and non vaccinated dams. High significant reverse correlations were noticed between serum IgM of vaccinated dams and their calves as well as between colostral IgG of non vaccinated dams and serum of their calves. A significant positive correlation between colostral IgA of vaccinated dams and serum of IgA of their calves was observed. The previous results of immunization of pregnant buffalo dams with [lactovac vet] revealed that there was a striking increase in the level of both serum and colostral immunoglobulins of vaccinated dams in comparison with non vaccinated dams as well as in serum of 36-48 h old calves born to vaccinated darns in comparison to those born to non vaccinated darns. Clinical observations of neonates [test and control groups] clearly demonstrated that [Lactovac vet] induced a pronounced decrease in the incidence of diarrhea, pneumonia and mortality rates. It is highly recommended that a program depending on vaccination of darns during late gestation with [Lactovac-vet.] could successfully be used to protect neonates against the most prevalent diarrhoegenic agents and minimize a great economic loss