Effects of dill powder (Anethum graveolens dhi) on performance and biochemical traits, immune response, blood cells and microbial population of cecum broilers after stress induced with dexamethasone were investigated. Two hundred and forty broilers were arrayed in completely randomized design with six experimental groups, five replications and eight broilers per replication. The experimental groups consisted of G1: control diet without additives, G2: control diet supplemented with 1.5% dill powder, G3: control diet supplemented with 1.5% dill powder under dexamethasone stress, G4: control diet supplemented with 3% dill powder, G5: control diet supplemented with 3% dill powder under dexamethasone stress, and G6: control diet under dexamethasone stress. After 31, 33, 38 and, 40 days, 2 mg/kg bodyweight (BW) dexamethasone was injected in right chest muscle in groups 3, 5, 6, and samples were taken after 35 and 42 days. Use of 3% dill powder reduced cecum microbial population significantly. Under dexamethasone oxidative stress conditions dill powder improved biochemical traits and the number of white blood cells significantly. Without stress induced by dexamethasone injection, use of 3% dill powder improved internal organs, increased the length of the digestive tract, improved weight gain, reduced FCR and improved antibody titers to Newcastle disease (ND) and avian influenza (AI) viruses. All levels of dill powder prevented negative impacts of dexamethasone on functional and biochemical traits. Thus, 3% dill powder has beneficial effects on performance, immune response, blood cell and microbial population, and could be used as a growth promoter and to prevent oxidative stress.

ABSTRACT The current study was conducted to examine the effects of an herbal compound, a probiotic and an antibiotic growth promoter (AGP) on the performance, intestinal bacterial population, antibody titers, and morphology of the jejunum and ileum of broilers. A number of 240 male Ross 308 broilers were distributed into four treatments, with five replicates of 12 bird each. The experimental period was 42 days. Treatments includes: 1) basal diet; 2) basal diet supplemented with an AGP (phospho-flavomycin at 450 mg/kg of diet); 3) basal diet supplemented with a Lactobacillus-containing probiotic (250 mg/kg of diet); and 4) basal diet supplemented with an herbal compound (containing thyme, oregano, chamomile, and peppermint essential oils at 1 g/kg of diet). Body weight (BW) and cumulative feed intake (CFI) were measured weekly. Blood parameters, intestinal morphology, vaccine immunity titers, and intestinal microbial population were measured on day 42. The results showed that probiotic and herbal compound supplementation significantly increased body weight (BW) and decreased feed conversion ratio (FCR) (p<0.05), in comparison with the basal diet. A significant increase in vaccine titers against Avian Influenza, Newcastle disease, and Infectious Bursal Disease were achieved with the treatment with herbal compound supplementation. Herbal compound significantly reduced triglycerides, cholesterol, LDL concentration and ALP, AST and ALT activities and increased the HDL levels in blood serum of chicks (p<0.05). The bacterial load of E. coli, Salmonella and coliforms of the AGP-fed group was significantly lower than those fed the control diet. Significant increases in villus height and decrease in crypt depth and goblet cells were seen in the ileum and jejunum of probiotic-fed broilers (p<0.05). In conclusion, better overall immune status and blood biochemical parameters were obtained with the herbal compound than with the probiotic; however, the performance of broilers fed the probiotic was better than that of the broilers fed the herbal compound and the AGP.

The aim of this study was to compare the effects of a new multispecies probiotic containing four Bacillus species and Saccharomyces boulardii (Microguard®) with a commercial probiotic (Protexin®) and a commonly used antibiotic in broilers. Six hundred one-day-old male Ross 308 broilers were randomized to six experimental treatments, with five replicates of 20 chicks each, for 42 days, receiving an ad libitum corn-soybean basal diet. Treatments were added to the basal diet and consisted of tetracycline as an antibiotic growth promoter (500 g/ton), three dosages of Microguard (50, 100 and150 g/ton) or Protexin (100 g/ton). The control group received the basal diet with no additive. The group fed with Microguard at 150 g/ton showed increased final bodyweight, weight gain, high density lipoprotein, triglyceride, and antibody titres against Newcastle disease (ND) and avian influenza (AI) levels. Improved feed conversion ratio, increased villus height, and villus highest crypt depth ratio, along with lower plasma gamma-glutamyl transpeptidase, alkaline phosphatase, alanine aminotransferase, were found in probiotic-supplemented broilers. Carcass yield, liver weights, breast muscle values, and abdominal fat weights were reduced in groups fed with 100 or 150 g/ton of Microguard. Caecal coliforms, Salmonella and Escherichia coli numbers decreased in groups fed with 100 or 150 g/ton of Microguard. These results show that Microguard at 150 g/ton is a promising probiotic to replace antibiotics in broiler feed as a growth-promoter while enhancing immune system responses and inducing beneficial modulations in the caecal microflora.

ABSTRACT The present study was carried out to determine the effects of the inclusion of a spore-forming probiotic (Bacillus subtilis) in laying Japanese quail diets as an alternative to growth-promoting antibiotics to help produce healthy eggs and meat. This experiment was conducted as a completely randomized design with three treatments (control, 0.05% bacitracin methylene disalicylate (BMD), or 0.1% Bacillus subtilis) of five replicates of 11 quails each. Feed intake and egg production were recorded daily on cage basis. Body weight was determined at the beginning and end of the trial (36 and 42 weeks). At the end of the experiment (42 weeks), antibodies against Newcastle disease and avian influenza, egg components, Haugh units, eggshell quality and breaking strength, blood parameters, cecal microbial population, villus length, and crypt depth were measured. The dietary inclusion of Bacillus subtilis and BMD significantly (p≤0.05) increased egg production and egg weight; however, eggshell thickness and breaking strength, Haugh units, and eggshell percentages were not affected. The dietary addition of both products significantly (p≤0.05) decreased plasma cholesterol levels and increased LDL levels, as well as antibody levels against Newcastle disease and avian influenza (p≤0.01). In birds fed Bacillus subtilis and BMD, crypt depth was reduced, but villus height and villus to crypt ratio were significantly increased (p≤0.001) compared with those fed the basal diet. Cecal coliforms, E. coli, and Salmonella counts were reduced (p≤0.01) in quails fed the diets containing Bacillus subtilis and BMD compared those quails fed the non-supplemented diet. The results of this study demonstrated that in absence of AGPs, the inclusion of a spore-forming probiotic partially improves the performance of laying quails.