MATERIALS AND METHODS

Two hundred day old broiler chicks as a male from commercial strain (Arbor Acres) were utilized for 28 days experimental period in Iran. The chicks were randomly allocated to 20 pens containing 10 chicks each with 4 replicates and assigned to receive one the following dietary treatments: (1) basal diet (control), (2) basal diet + 0.01% Pediococus Acidilactici bacteria (Probiotic), (3) basal diet + 1% whey powder that contained 9% Cp and 75% lactose, (4) basal diet + 0.01% Probiotic and 1% whey powder, (5) basal diet + 0.005% Probiotic and 0.5% whey powder. The chicks were fed a starter diet from day 0 to 14 (Men = 3000 kcal kg^-1, CP = 21.2%) then switched to a grower diet from day 15 to 28 (MEn = 3060 kcal kg^-1, CP = 19%) of the experimental period (Table 1). Birds were fed ad libitum and water was available all times during the experimental period. Feed intake, body weight, feed conversion rate were measured weekly. At the end of experiment, two birds of each replicate were selected. All birds weighted, then decapitated and viscera were collected immediately. One gram of intestinal contents sampled and cultured on Violet Red Bile Agar (VRBA) medium for coli-form counting. Also rate of intestinal lactic acid were detected. Another sample from cecal obtained for pH measurement and number of oocyst counting. Effects of treatments on response variables were determined by Two-way ANOVA using commercially available statistical software SPSS. Significance of difference among source of variance was determined using the Dancan method. Difference among experimental groups were declared to be significant if probability was less than 0.05 throughout the study.

RESULTS AND DISCUSSION

Feed Intake
Results from variance analysis showed that diets used in starter and grower period was significant and mean of results obtained from different treatments are displayed in Table 2. At starter period, all treatments in comparison with control improved feed intake and these treatments as compared with each others did not have any significant difference (p<0.05). During the whole experiment period (0-28 day) broilers receiving Probiotic plus whey powder (0.01+1% and 0.005+0.5%) and also whey powder (1%), showed greatest amount of feed intake (p<0.05).

Table 2:	Effect of Probiotic and Whey powder on performance and gut micro flora of broilers
Mean in the same line with different superscripts are significantly different (p<0.05); *: Significant; **: Highly significant; NS: Non-Significant

Body Weight
Effect of treatments on body weight were significant at the end of starter and grower period. Average comparison (Table 2) showed that either at starter period or grower period, highest body weight belonged to broilers fed Probiotic plus whey powder (0.01+1% and 0.005+0.5%) and also whey powder (1%). These results disagrees with results of Jin et al. (2000) that expressed that adding lactobacillus to broilers diet caused to significant improvement in their weight and feed conversion. In this survey adding only probiotics dose not have any effect on broilers weight gain and it only caused to increase body weight when probiotics were used with whey powder.

Feed Conversion Ratio (FCR)
Feed conversion ratio was not affected significantly by treatment groups at starter period but was affected significantly at the end of grower period. All treatments except probiotic in comparison with control demonstrated best FCR (p<0.05). The obtained results are in accordance with the finding of Jin et al. (2000). In this research, probiotic caused to FC improvement when used with whey powder. Probiotics cause to useful microbes in digestive system overcome harmful microbes and this mechanism brings growth increase and FCR improvement and along with this, whey powder provides suitable condition for probiotic activity.

Escherichia coli
Number of E. coli was affected significantly by treatment (p<0.01). All treatments except control caused a significant decrease in number intestinal e-coli and these treatments as compared with each other did not have any significant difference (p<0.05). We can conclude that using Probiotic plus whey powder together or separately cause to decrease intestinal E. coli bacteria. Jin et al. (2000) announced that using lactobacillus decrease e-coli bacteria in broilers cecum. Lactose of diets contents is in opposite relation to intestinal pH. Increasing lactic acid caused a decrease in E. coli (Chambers et al., 1997). May be probiotic mechanism in decreasing pathogenic micro-organism is because of competitive exclusion or inhibitor production such as organic acid, Bacteriosin and Lactolin (Gardiner et al., 2004).

Lactic Acid
Effect of treatments on intestinal lactic acid were significant (p<0.01). The highest of intestinal lactic acid belonged to broilers that fed Probiotic plus whey powder (0.01+1%) and on the next rank belonged to treatment including Probiotic plus whey powder (0.005+0.5%) and also whey powder (1%). The results of recent research are completely in accordance with Jin et al. (2000) result which expressed adding lactobacillus to broilers diet caused a significant increase in total of cecal volity fatty acid.

Cecal Oocyst
Results from variation analysis indicate significant difference between diets in amount of oocyst in faeces of broilers cecum (Table 2). All treatments except control caused to significant decrease in number of cecal oocyst (p<0.05). Broilers which receive probiotic have much more lymphocyte and less oocyst than control treatment and these results show clearly that probiotic nutrition lead to development of digestive system and increase immunity against coccidosis (Dalloul et al., 2003). So we can conclude that, number of oocyst used as inner parasite in each treatment, has reduced by using of Probiotic and whey powder separately or together.

Cecal pH
Means of data obtained from different treatments are displayed in Table 2. All treatments except control caused a significant decrease in cecal pH (p<0.05). Lowering digestive system pH, because of whey powder intake and lactic acid producing bacteria, reduce activity of harmful organism like E. coli which activate in 8-9 pH (Glusen et al., 2002).

CONCLUSIONS

Using Probiotic plus whey powder show Synergetic effects in improving of broiler performance and decreasing of pathogenic micro-organism in digestive system and we reached to our final objective that it was eliminating antibiotic from poultry diet and producing safety meet.