Upregulation of Oxidative Burst and Degranulation in Chicken Heterophils Stimulated with Probiotic Bacteria

Abstract

The immune system of neonatal chicks is functionally immature during the first week of life. Researchers have previously demonstrated that the avian humoral response can be increased with probiotics. Although the humoral response provides the chick with an effective mechanism to combat pathogens, sufficient antibody titers are not attained until 7 to 10 d postinfection. However, the innate immune system (i.e., heterophils) can respond much more quickly to pathogens. The objective of this study was to determine whether probiotic bacteria can also upregulate heterophil function. Heterophils were isolated from the peripheral blood of neonatal chickens by using a discontinuous density gradient. Oxidative burst and degranulation are bactericidal mechanisms used by heterophils to kill pathogens and were used in this study as indicators of heterophil function. We found that each of the 10 "generally recognized as safe" probiotic isolates (designated G1 to G11) tested in vitro were capable of increasing (P < 0.05) heterophil oxidative burst and degranulation when compared with unstimulated controls. Bacillus subtilis (G3), Lactococcus lactis lactis (G6), and Lactobacillus acidophilus (G8) isolates were determined to elicit the greatest heterophil response in vitro and were subsequently fed to chicks. Phosphate-buffered saline or 1 of these 3 probiotic isolates (approximately 2.5 x 10(8) cfu/chick; 50 chicks/treatment) resuspended in PBS was administered by oral gavage on the day of hatch. Heterophils were isolated from chicks from each of these 4 treatment groups 24 h posttreatment. Significant increases in heterophil degranulation and oxidative burst were observed with the G3-, G6-, and G8-treated chicks when compared with heterophils isolated from birds with no probiotic treatment. These data suggest that probiotic bacteria can significantly improve heterophil oxidative burst and degranulation in broilers. To our knowledge, this is the first study demonstrating a relationship between probiotics and avian heterophil function.

Assessment of a probiotic Containing Bacillus Subtilis on the Performance and Gut Health of Laying Japanese Quails (Coturnix Coturnix Japonica)

“…Most of probiotics benefit the host by immune regulation, particularly through the balanced control of pro-inflammatory and anti-inflammatory cytokines (Li et al, 2009;Foligne et al, 2010;Jobin, 2010). Several studies have provided unequivocal evidence that certain probiotics strains are able to stimulate several aspects of innate (Farnell et al, 2006;Boirivant et al, 2008;Romanin et al, 2010;Weiss et al, 2010) and humoral immunity (Galdeano et al, 2009). Moreover, the extracellular enzymes produced by Bacillus subtilis may boost the general gut immune function (Chen et al, 2009).…”

Probiotics for Human and Poultry Use in the Control of Gastrointestinal Disease: A Review of Real-World Experiences

“…Balanced gastrointestinal microflora and immune-stimulation or regulation of cell mediated or humoral immunity are major functional effects attributed to the consumption of probiotics [18,26,[32][33][34][35][36]. However, several animal and human studies have provided unequivocal evidence that specific strains of probiotics are able to stimulate multiple aspects of innate immunity [3,8,20,[37][38][39][40]. The importance of the intestinal microflora composition in physiological and pathophysiological processes in the GIT, is becoming more evident and has led to new possibilities for prevention and therapy of diseases [4,18,41].…”

“…Extensive laboratory and field research conducted with this defined LAB culture has demonstrated accelerated development of normal microflora in chickens and turkeys, providing increased resistance to Salmonella spp. infections [37,[67][68][69][70][71][72]. Published experimental and commercial studies have shown that these selected probiotic organisms are able to reduce idiopathic diarrhea in commercial turkey brooding houses [73].…”

In ovo and Dietary Supplementation of Probiotics Affects Post-Hatch Expression of Immune-Related Genes in Broiler Chicks

“…The immune system of the neonatal chick is immature and inefficient during the first week of life, rendering the bird extremely vulnerable to infectious threats found in the environment [1]. Immunomodulators are currently being studied and sought after to counteract the inadequacies of the chick immune system and promote host defense during this immunologically liable time.…”