Enhanced mucosal immunity against Eimeria acervulina in broilers fed a Lactobacillus-based probiotic

Abstract

The effect of feeding a Lactobacillus-based probiotic on intestinal intraepithelial lymphocyte (IEL) subpopulations and subsequent protection against coccidiosis was investigated in broiler chickens. Day-old male broilers were fed standard rations without control (CONT) or with a commercial probiotic (PROB) Primalac. Differences in IEL subpopulations were assessed by flow cytometry at 21 d postprobiotic treatment. At 25 d of age, a group of randomly selected birds from each diet was inoculated orally with 10,000 (per bird) sporulated oocysts of Eimeria acervulina and kept on the same diets. Fecal material, sera, and intestinal washes were collected 10 d postchallenge with E. acervulina. Birds on the PROB diet had more IEL expressing the surface markers CD3, CD4, CD8, and alphabetaTCR than those of the CONT diet. The probiotic-fed chickens produced less oocysts (P < 0.0001) compared to the untreated, control group (368 x 10(6) in CONT vs. 89 x 10(6) in PROB). The interferon-gamma levels in both serum and intestinal secretions were not significantly different between the two groups. However, CONT group showed higher antibody levels against a recombinant coccidial antigen in the intestinal secretions than the PROB group. No significant difference was found in serum antibody levels against the same antigen. These results dearly indicate that the probiotic bacteria impacted the local immune response as characterized by altered IEL subpopulations and increased the birds' resistance to E. acervulina as reflected by reduced oocyst shedding.

Intermittent feeding programme and addition of &lt;i&gt;Bacillus subtilis&lt;/i&gt; based probiotics to the diet of growing broiler chickens: Influence on growth, hepatic enzymes and serum lipid metabolites profile

“…Today, addition of probiotic in diet is a common strategy for animal nutrition, because probiotic is a natural growth promoter instead of feed antibiotic (Rekiel et al 2007). Adding probiotic in the diet improves the animal immune system and the host's resistance to enteric pathogens, affects intestinal morphology as well as intestinal function, feed conversion, weight gain and performance of birds (Dalloul et al 2003, Chichlowski et al 2007, Vila et al 2009, Ohh 2011. Li et al (2006) also reported that addition of Bacillus subtilis culture to the layer diet decreased cholesterol concentration in egg yolk.…”

New probiotic strain Lactobacillus fermentum AD1 and its effect in Japanese quail

“…(Pascual et al, 1999), Campylobacter sp. (Stern et al, 2001) and, more recently, Eimeria acervulina (Dalloul et al, 2003). Proposed mechanisms of pathogen inhibition by the probiotic microorganisms include competition for nutrients, production of antimicrobial conditions and compounds (volatile fatty acids, low pH, and bacteriocins), competition for binding sites on the intestinal epithelium, and stimulation of the immune system (Rolfe, 2000).…”

Adaptive response to Eimeria acervulina in rearing hens is affected by suboptimal incubation temperature and heat exposure in later life

“…The output of oocysts in the faeces is a widely used method in disease diagnosis and also a measure for the infection severity (Chapman and Rayavarapu, 2007). Furthermore, it says something about the chickens' resistance to Eimeria (Dalloul et al, 2003), the higher the oocyst production, the lower the resistance to Eimeria. These observations all indicate that SI chickens had a lower capacity to adapt during the E. acervulina infection than OI chickens.…”