Experimental infection of commercial layers using a Salmonella enterica serovar Gallinarum strain: Leukogram and serum acute-phase protein concentrations

Abstract

The aim of the present study was to evaluate white blood cell counts and serum protein profiles of commercial layers experimentally infected with Salmonella Gallinarum (SG) in order to better understand the pathophysiology of the disease caused by this bacterium. 180 five-day-old commercial layers were divided into 3 groups (G); G1 and G2 received 0.2 mL of inoculate containing 3.3x10(8) CFU or 3.3x10(5) CFU SG resistant to nalidix acid (Nal r)/mL, respectively, directly into their crops. G3 group did not receive the inoculum. Birds were sacrificed 24 hours before (T1) and 24 hours after the infection (T2), and three (T3), five (T4), seven (T5), and ten (T6) days after the administration of the inoculum. White blood cell counts were carried out in a Neubauer hemocytometer and in blood smears. Serum protein concentrations, including acute-phase proteins, were determined using sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Data were submitted to analysis of variance, and means were compared by Tukey's test (P <0.05). G1 and G2 groups presented higher leukocyte counts on T4 and T5, respectively, due to the increase of circulating lymphocytes and heterophils, with a significant difference relative to G3. In electrophoresis, an increase in the serum levels of ceruloplasmin, haptoglobin, and hemopexin and a decrease in transferrin, which are acute-phase proteins, was verified. IgA serum levels did not change; however, IgG concentration increased during the infection. In conclusion, the results provide information for the better understanding of the pathophysiology of fowl typhoid

Recovery of Salmonella Gallinarum in the Organs of Experimentally-Inoculated Japanese Quails (Coturnix coturnix)

“…Several studies with chickens have reported some of the clinical signs that were observed in the present study, such as closed eyes (Freitas Neto et al, 2007), ruffled feathers and diarrhea (Alvarez et al, 2003), and apathy (Garcia et al, 2010). Also, some of the gross changes observed during necropsy were consistent with those found in chickens, including hepatomegaly and hemorrhagic ovarian follicles , as well as deformed and congested liver (Hossain & Islam, 2004).…”

Molecular and Cellular Characterization of a Salmonella enterica Serovar Paratyphi A Outbreak Strain and the Human Immune Response to Infection

“…In humans, an acute inflammatory disease, particularly due to bacterial infection, is often associated with a high WBC count (39,44). An accumulation of circulatory leukocytes has been documented in several Salmonella-infected animals, including monkeys (11), fowl typhoid in chickens caused by S. Gallinarum (16), and in murine typhoid mediated by S. Typhimurium infection (10). To examine whether paratyphoid patients demonstrate increased WBC levels (leukocytosis) during their acute infection, peripheral WBC counts of 24 hospitalized paratyphoid patients were compared to those of a control group of 23 patients with invasive E. coli infections.…”

Dietary Bacillus subtilis B2A strain in laying hens challenged with Salmonella gallinarum: effects on egg production, egg quality, blood haptoglobin and targeted intestinal Salmonella shedding

“…Groups of commercial layers in a S. gallinarum challenge experiment showed an increase in the serum levels of haptoglobin, which is an acute-phase protein, as compared to the control group (Garcia et al 2009). Reduced concentration of haptoglobin due to B. subtilis feeding in these Salmonellachallenged laying hens could be attributed to reduction in infection-induced stress and the related injuries.…”