A total of 720 Ross 308, male broiler chicks were used to study the effect of feed form, corn particle size, and probiotic supplementation as a completely randomized block design with 2*2*2 factorial arrangement (eight treatments and five replications). The factors included the type of feed (pellet or mash), the average size of corn particles (590 and 1220 urn), and the addition or absence of a probiotic (DIPro) to the diet. At the end of the experiment, relative weights (% of BW) of abdominal fat and gizzard were calculated as a percentage of live weight. Using pellets increased the body weight gain (BWG), feed intake (FI), and improved feed conversion ratio (FCR). Feeding coarse corn particles substantially reduced the body weight gain and increased the feed conversion from 1 -10, 25-42, and 1 -42 days of age. Feed intake reduced from 1 -42 d and 42-25 d by consuming coarse corn particles. The use of probiotics increased feed intake and body weight gain from 25-42 and 1 -42 d. The pelleted diet increased gizzard and proventriculus pH, whereas coarse corn particles reduced pH. The pelleted feed decreased the relative weight of the gizzard and increased the abdominal fat percentage. Coarsely ground corn increased the abdominal fat and gizzard percentage. Probiotic supplementation improved feed intake, body weight gain, and feed conversion from 1-42 d. Pelleted feed plus probiotics and a 590-um particle size produced the best performance in broilers.

ABSTRACT The objective of the present study was to evaluate the effects of in ovo infusion of probiotic strains (Bacillus subtilis, Enterococcus faecium, and Pediococcus acidilactici ) on jejunal microbial population and mucin gene expression in broiler chicken. In a completely randomized design, 0.5 ml of mediums containing 107 cfu of different probiotic strains, was administered into amniotic fluid of the 480 Cobb fetus (day 18 of incubation), with four treatments, five replicates with twenty four eggs each. For mucin gene expression, samples from the jejunum were taken on day 21 of incubation and day 3 post-hatch. Microbial profile was determined for total lactobacillus and E. coli by sampling jejunal contents on days 1 and 3 of age. Expression of the mucin gene in the jejunum was higher (p<0.05) in chicks that received Bacillus subtilis in comparison with the control group. Infusion of the probiotic strains had no effect on jejunal E. coli and lactic acid bacteria populations on day 1 post-hatch (p>0.05). There were no significant differences among treatments for performance parameters at different periods and the whole period. It was concluded that infusion of probiotic bacteria during the late of incubation has no effect on feed intake, gain and feed conversion ratio, but has a positive effect on mucin gene expression in the jejunum. The best probiotic strain for mucin gene expression was Bacillus subtilis and for beneficiary bacteria colonization was Bacillus subtilis and Pediococcus acidilactici .

The aim of the present study was to investigate interactions between feed form and dietary inclusion of probiotics (live organisms) and enzymes on growth performance, cellular and humoral immunity, and relative weights of lymphoid organs of broiler chicks fed a triticale-based diet. A total of 640 broiler chicks were allocated to eight treatments when they were one day old, with four replicates (n = 20 chicks in each). The dietary treatments consisted of feed form (pellets or mash) and dietary supplementation with or without a Bacillus-based probiotic (0.03% diet) and enzyme (carbohydrase, 0.05% diet) in a 2 × 2 × 2 factorial arrangement. Feed conversion ratio (FCR) was calculated based on feed intake (FI) and weight gain (WG). The WG of the broiler chicks fed the pelleted diets containing the enzyme and probiotic (alone or in combination) was greater than that of the birds fed the mash diets without these additives. Significant interaction effects of the enzyme and probiotic on FCR and FI were observed in the starter period. The heterophil : lymphocyte (H : L) ratio of the chicks fed the pelleted diet containing the enzyme and probiotic was lower than that of the birds fed the other diets. The cellular immunity of the birds fed this diet increased after 24 hours, as shown by the results of a challenge experiment with dinitrochlorobenzene (DNCB) or an injection of phytohemagglutinin (PHA). In conclusion, feed form and supplementation of a triticale-based diet with feed enzymes and probiotics can greatly improve the growth performance and immunity of broiler chicks.

ABSTRACT An experiment was conducted to determine the effects of the dietary inclusion of different levels of thymoquinone (TQ) of broilers subjected to oxidative stress or not on the antibody titers against Newcastle disease and on the gene expression of interleukine-1 and interferon gamma. A total of 320 one-day-old broilers was randomly assigned to eight treatments with four replicates of 10 birds each, in a 4 × 2 factorial arrangement, consisting of four thymoquinone (TQ) levels (0, 5, 8, or 11 mg/kg body weight) and two levels tert-butyl hydroperoxide (t-BHP) injection (0 or 0.02 mmol/kg of body weight). Blood samples were collected from two birds per replicate to determine antibody titers against Newcastle disease. At the end of experiment, two birds per replicate were randomly selected, sacrificed and their spleens were collected to evaluate the genes expressioninterleukin-1 and interferon gamma (p<0.05). The dietary inclusion of TQ of broilers subjected or not oxidative stress increased antibody production against Newcastle disease (p<0.05). Both individual and combined dietary inclusion of t-BHP and TQ promote the differentiation and proliferation of spleen cells and the gene expression of interleukin-1 and interferon gamma (p<0.05).