فصلنامه زیست شناسی جانوری تجربی
سال نهم شماره 4 (پیاپی 36، بهار 1400)

This experiment was conducted to investigate the effects of different levels of prebiotic (Fermacto) on performance and some blood parameters of broiler chicks under induced ascites. 240-old chicks from Ross 308 strain were randomly divided into three treatments and each treatment was divided into four replicates. The dietary treatments included: control and two levels (2 and 4 g/kg feed) of prebiotic (Fermacto). For ascites induction, all birds received 1.5 grams salt per liter from day 6 to day 13. The relative weight of the intestines was measured relative to the body weight at end of experiment. The birds of the negative treatments were subjected to an induction program. Prebiotic supplements were added to the feed from the 12th day of the experiment. Both prebiotic levels significantly reduced feed intake & reduced feed conversion and increased weight gain in comparison with control treatment (P<0.05). Both prebiotic levels significantly decreased the hemoglobin, red blood cells, protein and hematocrit in birds were induced ascites (P<0.05). Both prebiotic levels significantly decreased ascites and RV / TV index (P<0.05). The results of intestinal morphology indicated that the weight of the intestines (dissected from below the gizzard to the ileal cecal junction) was not significantly different between the experimental groups. in Conclusion, it is possible to successfully use a 2gg/kg diet of prebiotic (Fermacto) in broiler chickens as an effective factor in reducing functional problems and ascites mortality.

In this study, the effect of iron oxide nanoparticles on the structure, thermal stability and activity of bovine pancreatic trypsin was investigated. Various spectroscopic techniques including UV absorption, circular distortion, thermal stability, fluorescence and kinetics at pH 8 were used to achieve this goal. Thermodynamic and kinetic results showed that trypsin stability decreased in the presence of iron oxide nanoparticles and increased its activity. Fluorescence spectroscopy showed that the nanoparticles can reduce trypsin fluorescence through static quenching. Based on the thermodynamic parameters, the process of binding the nanoparticles to trypsin is performed as a spontaneous reaction which the electrostatic forces play the main role in. Circular dichroism studies showed changes in the secondary structure of trypsin as an increase in α-Helix l content and a decrease in β-sheets. UV spectroscopy showed that iron oxide nanoparticles bind to trypsin and cause changes in protein structure. The interaction studies of Fe3O4 nanoparticles and trypsin show that not only water and solvent molecules can affect on 3D structure of trypsin and protein but also play an important role in adsorption nanoparticles.

Rice stem borer, Chilo suppressalis Walker (Lepidoptera: Crambidae) is the key pest of paddy fields in northern Iran which the overwintering larvae look for shelters after rice harvesting. Since these natural shelters are the main infestation centers for the next crop year, an investigation included two experiments was conducted in 10 localities of Mazandaran province (including, Mahmud-Abad, Fereydon-Kenar, Babolsar, Hassan-Abad, Naej, Babolkan, Haraz, Bandpey, Nezam-Abad, Amol Rice Research Institute) for three years. The conducted experiments were: Appointment of population transportation process of overwintering larvae and appointment of rice infestation to the larvae in cultural season. The results indicated that the highest density of living larvae was determined in the first stage of sampling (after crop harvesting) in Babolsar, Fereydon-Kenar and Amol, and the lowest one was obtained in the last stage of sampling (February) in Haraz region. The highest (%1.25) and the lowest (%0.87) percent of dead heart were obtained in Fereydon-Kenar and Haraz, and the highest (%1.3) and the lowest (%0.88) percent of white head in Babolsar and Bandpey, respectively. The results of faunistic surveys indicated that there is a diverse fauna of natural enemies (predators and parasitoids) of C. suppressalis in paddy fields of Mazandaran province. In total, 30 species of predators (Aves: 4 species; Chilopoda: 3; Araneae: 5; predator insects: 18), and 28 species of parasitoids of Acari (one species) and parasitoid insects (27 species) were collected and identified.

Praying mantis are a small order of insects,that consisting of 2452 species of 446 genera and 15 families worldwide. They are active predator and feed on the different types of insects such as locusts and the other insects and even the vertebrates like snakes and lizard. The present study was carried out to investigate the faunistic of mantis in Lahijan and suburbs during the years of 2018-2019. In this regard, the city of Lahijan was divided into 10 stations based on different ecological factors. Sampling were done directly and manually at equal times during spring, summer and autumn seasons. The collected samples were transferred to biosystematic laboratory of Shahid Beheshti University and were identified up to the level of genus and species with the help of stereo microscope and valid identification key such as Medditerranean Eurozone (Battiston.etal., 2010), Four species among 120 species were identified. Which are: Mantis religiosa, Hierodula transcaucasica, Empusa fasciata, Bolivaria brachyptra were Identified.All the species were approved by professor Battiston and reported for the first time from Lahijan city, Guilan Province.

This study was conducted to investigate life history characteristics of Hircan crested loach (P. hircanica). A total of 150 specimens collected using electro-shocker from December 2015 to May 2016.  Results showed that the sex ratio of male to female is 1:0.65 indicating significant difference of males and females abundance in the studied population (χ2=6.83). The maximum observed total length and weight were 87 mm and 5.30 g for females, 104 mm 7.31 g for males. The weight - length relationship of female was W= 0.0085 TL2.89, of male W= 0.0109 TL2.74 and of the studied population was W= 0.0099 TL2.80. The growth model was isometric for females and negative allometric type for males and the population (t-test, tmale= 6.31, tfemale=1.61, tpopulation= 5.03, P<0.05). The average absolute fecundity was 328.86 per female and the relative fecundity was 110.56 eggs/g of females’ weight. Eggs diameters ranged from 0.45 to 1.79 mm with a mean value of 0.99 mm. The highest mean Gonadosomatic index (GSI) of the females was recorded in April, and of the males in May, indicating the highest reproductive activity of females and males occurs in June and May respectively.

This study was conducted to determine habitat connectivity and road crossing area for the Persian wild ass (Equus hemionus onager) in the Bahram-e-Goor Protected Area. In this research, habitat suitability modeling was carried out using 57 presence points of the species and six environmental layers implemented in the Biomod2 package in the R software based on four species distribution models. Then, the ensemble map obtained from the distribution models was used for habitat connectivity modeling using electrical-circuit method. Finally, the coincidence rate of road crossing with road collision points was assessed. Ourresults revealed that distance from moderate rangelands, distance from roads and slope had the greatest impact on habitat suitability of the Persian wild ass. Furthermore,results of the connectivity modeling revealed that there were high current movements of Persian wild ass individuals between Qatruiyeh National Park and western parts of the Bahram -e- Goor Protected Area. Eventually, seven road collisions were found to be in high coincidence with the modeled current movement along the west border of the Bahram -e- Goor Protected Area.This research highlights the necessity of provision of road crossing facilities (i.e., warning signs and lights, and speed control for vehicles) for conservation of the Persian wild ass by the Department of Environment in the study area.

Nigella sativa is an annual herbaceous plantthat has various pharmacological effects. In this research study, anti–microbial and anti–Alzheimer effects of aqueous and hydro–alcoholic extracts of N. sativa were evaluated. After identification of hydro–alcoholic extract compounds by GC–MS, anti–microbial activity indices including well diffusion, MIC and MBC for E. coli and S. aureus, were carried out by tube and agar dilution methods. In Anti–Alzheimer's effects of hydro–alcoholic extract of N. sativa on bovine serum albumin were examined using Congo–red spectrophotometry and transmission electron microscopy. Oleic acid (52.18%) followed by palmitic (19.77%) and linoleic acid (14.96%) were the major fatty acids in the extract. The amounts of MIC and MBC for both E. coli and S. aureus were 30.6 and 61 mg.ml-1 respectively in hydro–alcoholic extract. Well diffusion method showed highest antimicrobial activity against S. aureus with inhibition zone diameter of 22.67±0.29 mm, but aqueous extract did not any effects on bacteria. Congo–red spectrophotometry results showed that the absorbance of the protein sample (as a measure of amyloid fibril presence) was reduced by increasing the concentration of N. sativa extract and the lowest percentage of adsorption, compared to the control (extract less), was observed at the highest concentration of extract (20 μL). These results were confirmed by transmission electron microscope. The present study shows that the N. sativa seed, as a natural and valuable source, can be used for controlling the microbial infections and reducing symptoms in patients with Alzheimer's disease.