فهرست مطالب

  • Volume:2 Issue: 2, 2018
  • تاریخ انتشار: 1397/02/11
  • تعداد عناوین: 6
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  • Fatemeh Gholizadeh Pages 186-197
    Introduction

    The Effect of different levels of algae (Spirulina platensis) on growth performance, intestinal morphology, gut microflora and some blood parameters in broiler chickens was investigated in this study.

    Materials and methods

    Experimental diets included control diet (with no additive), 3 levels of algae (1, 1.5, 2 g/kg diet), and one level of prebiotic (1 g/kg diet) as a positive control were fed to birds from 1 to 42 d of age.

    Results

    The results showed that adding Spirulina algae to diet increased body weight gain and decreased feed conversion ratio during starter (1-10 d), grower (11-28 d) and whole period of rearing (1- 42 d) in comparison with other groups (P<0.05). The concentration of white blood cells, IgY, IgM, Ca and P in blood serum of broilers fed with 2 g alga/ kg diet was higher than other groups, however, the concentration of malondialdehyde (MDA) was lower (P<0.05). Supplementation of diet with alga increased the number of lactobacillus in gut (P<0.05). Also, villus height and the ratio of villus height/crypt depth in duodenum, jejunum and ileum of broilers fed with 2 g alga/kg was higher than other groups (P<0.05).

    Discussion and conclusion

    In conclusion, Spirulina algae supplementation improved growth performance, villus height, WBC count and decreased MDA in serum of broiler chickens, so it can be considered as a useful additive in broiler chickens diet.

    Keywords: Spirulina, intestinal morphology, gut microflora, broiler chicken
  • Fereidun mohebbi, Masoud seidgar, Ali Nekuiefard, zhaleh Alizadeh Pages 198-210

    This study was performed to determine relationship between dam reservoir physico-chemical parameters and the phytoplankton structure in 7 reservoirs of west Azarbaijan province. Samplings were carried out during July 2016. Samples were collected for phytoplankton identification and enumeration, chemical analyses at each sampling site. Principal component analysis (PCA), Detrended Correspondent Analysis (DCA) and two-way unweighted pair group method with arithmetic mean (UPGMA) were performed to determine the environmental variables affecting phytoplankton community dynamics. Seventy-three species belonging to five divisions were determined during this study. The result of PCA and DCA was confirmed by UPGMA analysis, in which three main groups were clustered on the basis of their correlation with phytoplankton community changes and environmental parameters. Totally, highly disturbed reservoirs contained different phytoplankton community than undisturbed ones.

    Keywords: PCA, DCA, reservoirs, phytoplankton, west Azarbaijan
  • Maryam Ameri, Najme Gord Noshahri, Razieh Ghazi Birgandi, Behrouz Jalali Ghassam Pages 211-217

    C-Phycocyanin is a natural pigment that has several applications in food and cosmetic industry. Recent studies have also revealed the medicinal effects of this natural blue dye. In this study, Comparison effect of mechanical (freezing and thawing, sonication and bead milling) along with chemical (inorganic acid, buffers and sea salt) extraction methods were carried out on C-Phycocyanin concentrations to achieve the optimum conditions of phycocyanin extraction from Spirulina platensis . Our result authenticated that repeating temperature cycles obtained higher phycocyanin concentration which could observed clearly by unaided eye. The optimum condition for extraction is freezing and thawing method under -20 °C condition in five repeated cycles in comparison with liquid nitrogen at the same condition. The best solvent was determined sea salt solution then distilled water, PBS and TE buffer, respectively. Under optimize condition phycocyanin was extracted with a concentration of 0.29 mg/ml and purity ratio (A620/A280) of 3.42.

    Keywords: Spirulina, C-phycocyanin, freeze-thaw extraction, sonication, solvent
  • faedeh Amini, Hossein Riahi, Hossein zolgharnien Pages 218-236

    Padina is a marine brown macro-algal genus, comprising of about 37 species. Information about the representatives of this genus along the Persian Gulf coast is limited to a few floristic surveys. The present work presents the results of a discussion about the Padina along the Persian Gulf coast, with emphasis on the molecular taxonomy. Sequences of the large subunit of RUBISCO (rbcL) have been used in the molecular analysis of species and for phylogenetic purposes. Based on the rbcL sequences, four species are recognized along the Persian Gulf coast: Padinasp.FA, Padina sp.PG,Padina sp.INDEGRO32 and Dictyota ciliolata.A new species, Padina sp.PG nov. is described based on morphology and molecular analyses. Twelve new sequences were generated among the samples examined.

    Keywords: Macroalgea, Padina sp.PG nov., Systematic, molecular
  • Maedeh Davari, Zakieh Modaressi, Zeinab Aghashariatmadari Pages 237-253

    Floristic study of cyanobacteria in the terrestrial habitats of Iran, revealed several taxa belonging to seven genera. Soil samples were collected from natural habitats of medicinal plant, Tanacetum parthenium, located in four provinces of Iran (Qom, Isfahan, Lorestan, Razavi Khorasan Provinces). All provinces studied are located in semi-arid regions of the country. The results of this study indicated the presence of 13 species belong to three families of cyanobacteria. Among these families, Nostocaceae with four genera and eight species showed the highest diversity, whereas Rivulariaceae with one genera and one species exhibited the lowest diversity. Among several heterocystous and non heterocystous taxa, Nostoc and Oscillatoria were found to be the most dominant genera in almost all the studied sites. Two reported species of genera Wollea and Cylindrospermum in present study, also have limited distribution in terrestrial habitats of Iran. Therefore, part of the current systematic study has been done with emphasis on these two specific taxa. A distribution of local area and camera lucida pictures of identified taxa is subjected in this study.

    Keywords: Blue-green algae, Diversity, Iran, Nostocaceae, Terrestrial habitat, Tanacetum parthenium
  • Javid Imanpour Namin, Saeedeh Ghassemi, Zohreh Ramezanpour, Fatemeh Ghanbari Pages 254-263

    Effects of photoperiod, light intensity and nitrate levels on growth (cell number) and biomass of Scenedesmus dimorphus was studied. Three levels of photoperiod 12:12, 8:16 and 16:8 hours dark: light, light intensity of 3000, 5000 and 7000 lux and nitrate levels of 1.47, 2.94 and 4.41 mmol/l were set up. Algae culture was performed at 28±2 °C in BBM culture medium. Algae cells were counted every three days for one month. By the end of experiments the lowest cell concentration (93×105 cell/l) was observed at 12:12 photoperiod, 1.47 mmol/l nitrate and 3000 lux light intensity and the highest cell concentration at 8:16 photoperiod, 2.97 mmol/l nitrate and 3000 lux light intensity. Increase in photoperiod correlated with significant increase in cell concentration. Higher light intensity with lower nitrate levels resulted in higher cell concentrations. The lowest algal biomass (1.38 gr.) was observed at 12:12 photoperiod, 3000 lux light intensity and 1.47 mmol/l nitrate levels while the highest biomass (5.2 gr.) at 8:16 photoperiod, 7000 lux light intensity of and 2.94 mmol/l nitrate level.

    Keywords: Scenedesmus dimorphus, light intensity, photoperiod, growth rate, fatty acids