نشریه پژوهش در تغذیه دام
سال یکم شماره 2 (پاییز و زمستان 1393)

This experiment was conducted to investigate the effect of supplementation of the diet (concentrate, corn silage, and corn silage and concentrate mixture) with different levels of an exogenous enzyme complex on gas production parameters. For each of the three sections, dietary treatments were: 1) basal diet (no mixing enzyme, control), 2) basal diet + 0.50 g of the enzyme mixture / kg DM, and 3) basal diet + 0.75 g of enzyme mixture / kg DM. Pressures recorded by the manometer method used to predict gas produced from the cultures fermented for 2, 4, 6, 8, 16, 24, 36, 48, 72, 96 and 120 hours after incubation. Unsupplemented diets showed a significant increase in the amount of gas produced in the three portions of the diet (P<0.05). Using the enzyme mixture at the level of 0.75 g/kg DM, caused a significant decrease in the amounts of gas produced in the mixture of concentrate and corn silage, and corn silage (P<0.05). Gas production rate was also significantly affected by different levels of the enzyme mixture (P<0.05). It seems that enzyme levels used in this experiment, did not improve the potential of gas production and nutritive value of different portions of ration. Further study is needed to achieve the effect of enzyme supplementation on gas production parameters.

Twenty-five Baluchi castrated lambs were used in a completely randomized design to measure voluntary feed intake and digestibility of corn silage alone (control), corn ensiled with 0.7 and 1.4% urea, and corn ensiled with 20 and 40% dairy cattle manure. Experiment duration was 28 days and contains three stages of adaptation, voluntary feed intake measurement, and digestibility trial. There were significant difference (P<0.05) among pH and chemical composition of different treatments. The highest percentage of natural detergent fiber (NDF), acid detergent fiber (ADF), ash and pH were observed on corn silage ensiled with 40% cattle manure. The results of voluntary feed intake showed that difference among treatments were significant (P<0.05). Among treatments, corn silage treated with 1.4% urea had the highest and corn silage ensiled with 20% dairy cattle manure had the lowest voluntary feed intake. The results also showed that digestibility of all nutrients except ether extract were significant among treatments (P<0.05). Digestibility of dry matter, organic matter, crude protein, crude fiber, NDF and total digestible nutrient were the highest on feed containing corn silage ensiled with 1.4% urea; whilst the feed containing cattle manure had the lowest nutrient digestibility. Results showed that adding urea to corn silage, caused an increase in dry matter digestibility and voluntary feed intake. Adding cow manure increased the amount of crude protein but reduced feed intake and digestibility of nutrients.

The purpose of this study was to examine the effect of probiotic as growth promoters and different nutrient density on the performance, immune response, and some blood parameters of broiler chickens. A total of 400 one-day-old Ross broilers were assigned to 1 of 4 treatments in a 2 × 2 factorial arrangement (5 replicates with 20 broilers per replicate) and fed 1 of 4 diets: two levels of nutrient density [high nutrient density (ME 2950 kJ/kg and CP 21.5 %/kg for 0-10 d; ME 3050 kJ/kg and CP20.3 %/kg for 11-24 d; ME 3150 kJ/kg and CP18.7 %/kg for 25-42 d) or low nutrient density (ME 2850 kJ/kg and CP 20.7 %/kg for 0-10 d; ME 2950 kJ/kg and CP19.6 %/kg for 11-24 d; ME 3050 kJ/kg and CP18.1 %/kg for 25-42 d)] and also two levels of probiotics 0 or 1.5 %/kg (65× 107 viable spores/g of Bacillus subtilis). Probiotic and nutrient density had no significant effect on performance of broiler chickens. Serum cholesterol and triglyceride concentration was decreased by low nutrient density diet (P<0.05). Dietary probiotic increased the blood lymphocyte percentage. Probiotic and density had significant effect on hetrophils and H/L ratio and decreased lymphocytes count at the end of expriments (P<0.05).

Two hundred and forty male day-old broiler chicks (Ross 308) were randomly assigned to five dietary treatments including: a corn-soybean meal basal diet (control); basal diet + 0.25% garlic powder; basal diet + 0.25% fresh ground garlic; basal diet + 0.5% garlic powder; basal diet + 0.5% fresh ground garlic. Feed intake (FI), body weight gains (BWG), and feed conversion ratios (FCR) were recorded periodically. On day 42, two chickens form each replicate were randomly selected, and after blood sample collection via brachial vein, euthanized and visceral organs, abdominal fat pad, heart, right ventricle, and total ventricles were weighed. Blood samples were used for measurement of nitric oxide (NO) and malondialdehyde (MDA) concentrations. Inclusion of garlic powder or fresh ground garlic into diet at the levels used in this experiment had no significant effect on FI, BWG, FCR, and carcass yield (p>0.05). However, Inclusion of 0.5% garlic powder into diet caused a significant increase in relative weight of bursa of Fabricius (p<0.05). Both levels of dietary fresh ground garlic (0.25% and 0.5%) caused a significant increase in serum MDA concentrations compared to control group (p<0.05). Dietary garlic powder at 0.25% inclusion rate caused a significant increase in serum NO concentration compared to control group (p<0.05). Overall, it is concluded that dietary garlic powder at the level of 0.25% would be advisable due to its desirable effects on NO concentrations.

An experiment was conducted with 240 Ross broiler chicks (mixed male and female) to evaluate the effect of ethanolic extract of pennyroyal in comparison with flavomycin antibiotic growth promoter (AGP) on blood biochemical parameters, weight of internal organs and cecal bacterial counts in broilers. The experiment was conducted in a completely randomized design manner with 4 treatments, 3 replicates and 20 chicks in each replicate from 1 to 42 days of age. Treatment 1 was a control basal diet, treatment 2 was the basal diet with 0.45 % AGP and treatments 3 and 4 received 0.1 and 0.05 % pennyroyal ethanolic extract in the basal diet, respectively. The results showed that the ethanol extract of pennyroyal in both used concentrations, reduced harmful bacteria (coliforms, Salmonella and E.coli) in ceca (p<0.05)., No significant effect on the weights of internal organs was observed except for the gizzard. Ethanolic extraction of pennyroyal increased the serum cholesterol concentration and decreased the activity of ALT, when compared with control group.

This study deals with comparison between the efficacy of an immune stimulant herbal compound and a commercial probiotic containing lactobacilli on performance, blood biochemical parameters, Immune response and intestinal bacterial counts in broilers. Two hundred and twenty five unsexed Ross 308 were randomly allotted to 3 groups of 5 replicate and 15 chicks in each replicate and fed with following treatments: 1) Basal diet (no herbal compound and probiotic), 2) Basal diet + 0.025% commercial probiotic and 3) Basal diet + 0.1% of an immune stimulant herbal compound () for 42 days. Results showed that addition of herbal compound decreased feed consumption of broilers compared with control group numericaly and decreased the cholesterol and liver enzymes significantly (P<0.05) compared with probiotic treatment. Antibody titers values get improved by incorporation of herbal compound when compared with other treatments. Total number of salmonella and coliforms were lower in probiotic group, while in herbal compound treatment, salmonella counts was (P<0.05) higher and E.coli counts was lower than other two groups, significantly (P<0.05).