Application of combination, immunomagnetic separation plus multiplex PCR for the detection and identification of salmonella enterica subspecies enterica serovar typhimurium in bovine diarrhoeic fecal samples

A total of 400 bovine diarrhoeic fecal specimens were obtained and conventional microbial culture, immunomagnetic separation and multiplex PCR were simultaneously carried out on samples. For detection of Salmonella at genus level, inv-A universal primer was selected. In order to identifiing of Salmonella typhimurium, specific primers of Rfbj, Fljb and Flic related to gene sequence of O4, H2:1,2 and H1: i were used, respectively. Results showed, 33[8.5%]were culture positive for Salmonella serotypes. However, Salmonella typhimurium with[66.7%], Salmonella dublin[9.1%], Salmonella virchow[6.1%], Salmonella gloucester[6.1%], Salmonella enteritidis[3%], Salmonella georgia[3%], Salmonella augustenborg[3%]and Salmonella lindenburg[3%], were the most common isolated serovars, respectively. In the IMS+Multiplex PCR four amplified products[663,526,284 and 183 bp] were found in all specimens which had typhimurium serovar[1,4,5,12:i:1,2]from rfbj,fljb,inv-A and flic genes, respectively. Results showed that detection and identification of Salmonella typhimurium using specific primers of O4, H2:1,2 and H1: i antigens can be useful

effect of egg derived specific antibody and probiotic on prevention of salmonella enteritidis infection in broiler chickens

To evaluate the effect of probiotic [Primalac] and Salmonella enteritidis-specific IgY on prevention of Salmonella enteritidis infection in broiler chickens, four 33 week-old Single Comb White Leghorn hens were hyperimmunized with Salmonella enteritidis [SE] whole cell antigens obtained by ultrasonication and administrated at a protein concentration of 500 microg/ml after centrifugation. Primary immunization was performed with 250 micro g of the antigen prepared in equal volume of Freunds complete adjuvant and saline. Booster injections were done each 14 days for twice, using incomplete Freunds adjuvant. Bleedings were performed 20 days after first injection and eggs were collected. The presence of anti-Salmonella antibody IgY and IgG in egg yolk and serum respectively, was monitored by ELISA, during the immunization period. Body weight, feed intake and feed conversation were determined. Then two hundred forty male "Ross "day-old chicks were randomly assigned to 8 groups and 3 replications of 10 birds were grown for 56 days of experiment. Eight experimental groups identified with, S, P, A, SP, SA, AP, SPA, C. Four birds from four challenged groups [S], were orally inoculated with 0.5 Ml of S. enteritids that contained 1X10[6] cfu/ml on day 7. The groups that supplemented with antibody [A], received 15 ml of yolk contained antibody [1.5 ml/bird/day], from day 1 to end of the experiment. The probiotic treated groups [P] were received probiotic, 0.1% of feed and 0.5% of feed, during 1-21 and 22-56 days of experimental period respectively. One group as control [C] did not receive any treatment of probiotic and antibody. The test was completely randomized designed. In this project the SAS statistical program for parameter data and chi[2] test for non- parameter data. The results indicated that high titer polyclonal antibody may be obtained 20 days and 55 days after first immunization, in serum and egg yolk respectively. A-treated, P-treated and A-Ptreated groups had significantly lower fecal shedding [P < 0.01]. The antibody alone and A-P treated groups had a significantly lower concentration of SE cecal colonization. Antibody alone and A-Ptreated groups had a lower isolation of SE from the liver, spleen and ileume. There were no significant differences [P > 0.05] in the mean body weight, mean daily feed intake, feed conversation ratio and mortality rate among the experimental groups at any period of experiment, but in the A-, P-, and A-P treated groups, daily weight gain significantly increased during finisher period and at day 49 [p < 0.05]

Bronchoalveolar lavage and bacteriological findings in calf pneumonia

This study was done for identification of bacterial agents in calf pneumonia and determination of their antimicrobial susceptibility. Bronchoalveolar lavage was done on fourteen pneumonic and seven normal Holstein calves between 1-3 month old. In bacteriological examination on the fluid of bronchoalveolar lavage, Mycoplasma spp. were isolated from 4 [28.6%] pneumonic calves and 1 [14.3%] healthy calf. Furthermore, Arcanobacterium pyogenes was isolated from 3 [21.5%] pneumonic calves and 1 [14.3%] healthy calf. However, Fusobacterium necrophorum, Actionobacillus [Pasturella] urea, Neisseria mucosa, Staphylococcus aureus, Cardiobacterium hominis were isolated from one pneumonic calf. This is the first report of Cardiobacterium hominis from the lung of a pneumonic calf. All of the isolated bacteria had the highest susceptibility to florfenicol