BACKGROUND: Extracts rich in phenolic compounds have an important role in antioxidant and antimicrobial effects, and pistachio green hull extract is rich in polyphenolic compounds. OBJECTIVES: The aim of this study was to evaluate the effect of green peel of Kalleqouchi and Fandoghi pistachio extract on performance, relative weight of carcass components, blood indices and intestinal microbial population of broiler chickens challenged with Staphylococcus aureus. METHODS: A total 168 one-day-old broiler chicks were randomly divided into six treatments, four replications and seven chicks. Experimental treatments included unchallenged groups (negative control) and chickens challenged with Staphylococcus aureus and fed 0, 200 and 400 mg / kg of aqueous extract of Kalleqouchi pistachio and 200 and 400 mg/ kg of pistachio Fandoghi green extract. All infected chicks were inoculated with oral solution containing 3 x 109 CFU of Staphylococcus aureus. Performance characteristics, immunity, blood indices and microbial population of the intestine were determined. RESULTS: The aqueous extract of green pistachio inhibited the growth of Staphylococcus but the ethanolic extract inhibited the growth of lactobacilli. Growth performance of chicks was not affected by the experimental treatments except at day 24, when aqueous extract of 200 mg / kg led to higher body weight gain as compared to control (0.049). Kalleqouchi extract at 400 mg/kg level increased abdominal fat (P = 0.0005) and had no effect on relative weight of other carcass components. The 400 mg/kg Fandoghi green extract and 200 mg/kg kalleqouchi extract increased enzyme activity of alanine aminotransferase activity and decreased the concentration of blood total protein (P <0.01). The pistachios extracts at all levels increased total antibody titer compared to control (P <0.02). Pistachio extract reduced total bacterial population of jejunal area compared to negative control (P = 0.008). CONCLUSIONS: Application of aqueous extract of pistachio extract improves immune response, decreases blood lipids and intestinal microbial population of broiler chickens challenged with Staphylococcus aureus.

BACKGROUND: Heat stress declines the performance through physiologic changes of the poultry. OBJECTIVES: This experiment was conducted to evaluate the effects of different levels of L-carnitine on performance, carcass characteristics and some blood parameters of broiler chickens fed with high fat diets under heat stress. METHODS: Two hundred one-day-old broiler chicks (Ross 308) were used in a completely randomized design by four treatments and five replicates (pen) 10 birds in each replicate. The chickens of experimental treatments were fed with basal diet (control group) and the diets plus the different levels of 100, 200 and 300 mg/kg L-carnitine. The experimental diets were used during the finisher period (day 24 to 42 of age) and under heat stress (32±1ºC as cyclic from 9.00 AM to 5.00 PM). RESULTS: The results showed that the chicks fed with the highest L-carnitine had the higher weight gain during the finisher period as compared to control and the lower L-carnitine fed chicks (p<0.05). Furthermore, the feed conversion ratio of birds fed with the medium and high L-carnitine levels (100 and 300 mg) was lower than that of control birds (p<0.05). In orthogonal contrasts, L-carnitine supplementation caused the improvement in weight gain and feed conversion ratio during both the finisher and whole experimental periods (p<0.05). The consumption of highest L-carnitine decreased the abdominal fat as compared to control (p<0.05). In orthogonal contrasts, L-carnitine consumption caused the higher glucose and lower abdominal fat in comparison to control (p<0.05). CONLUSIONS: Totally, the results of recent experiment show that consumption of 300 mg/kg L-carnitine improves the performance of broiler chickens through the increase in dietary fatty acids and energy.