مجله پژوهشهای جانوری (زیست شناسی ایران)
سال سی و چهارم شماره 2 (تابستان 1400)

In the present study, the morphometric and meristic characteristics of 363 specimens of Rutilus kutum (Kamensky, 1901) collected from the Chelvand, Khalehsara, Sefid, Khoshk, Shir rivers and Anzali wetland, Chalous and Torkeman shores in the south Caspian Sea Basin were compared. All caught specimens were freshly transferred to the laboratory. In the Lab some 36 morphometric and nine meristic characters were measured and recorded. After standardization all data were analyzed using One-Way ANOVA, Duncan test, Canonical variate Analysis (CVA) and Cluster Analysis (CA). The results showed significant differences in 30 morphometric and two meristic traits between the studied populations (p < 0.05). The CVA was able to separate the studied populations and CA placed the Chalous populaion in a cluster separately from the others. Generally, the performance of the morphometric traits was superior to meristics in discrimination populations.Generally, the performance of the morphometric traits was superior to meristics in discrimination populations.

The Arsanjan county has various habitat types (grasslands, mountains, rocky and shrubbery areas) that is located northeast of Fars Province, Iran. The herpetofauna of Arsanjan county is unclear and there is no biosystematic study so far. The aim of the present study is to investigate the lizard’s fauna of Arsanjan. The study area is located between the coordinates as follow: 29°38' _ 30°00' N and 53°07' _ 53°43' E. All the specimens were collected in different regions of Arsanjan county during this survey from 2018 to 2020. Specimens were identified according to the valuable resources. The collected specimens represented ten species, nine genera and four families including: Large scaled rock agama (Laudakia nupta), Brilliant ground agama (Trapelus agilis) and Horny scaled agama (Trapelus ruderatus) (Agamidae); Keeled rock gecko (Cytopodion scabrum) (Gekkonidae); Snake-eyed Lizard (Ophisops elegans), Persian long tailed lizard (Mesalina watsonana), Persian racerunner (Eremias persica) and Zagrosian lizard (Timon princeps) (Lacertidae); Schneider Skink (Eumeces schneiderii) and southern grass skink (Heremites septemtaeniatus) (Scincidae). Among the identified species Timon princeps is a new record from the area.

Climate change is a major driver of species extinction, shifts in species’ phenology, distribution and morphology. Considering global warming impacts on different aspects of bird’s biology, especially on resident species living in lowland and warm areas, in this study, contemporary distribution points of Green Bee-eater in Fars province were combined with climate variables. Models were constructed using the maximum entropy algorithm implemented in MaxEnt 3.3.3 software. We evaluated the impacts of climate change using the General circulation model CCSM4 along with the concentration pathways RCP 2.6, RCP 4.5, RCP 6.0, RCP 8.5 from the IPCC Assessment Report 5. Climate suitability maps were constructed based on the average of ten replications by cross validation method. Modelling shows the distribution of this species is restricted to the lowlands of southern, central and western parts of Fars province and there are relatively large climatic potential areas in the southern half. Estimates of relative contributions of the climate variables to the Maxent models show that min temperature of coldest month is the most important variable, and areas with very cold winters are apparently not favorable for this species. To estimate the potential impacts of climate change on the species, the predicted potential areas in the future scenarios were compared with the current potential areas. Results predicted decline in climate suitability but no poleward range expansion. Therefore the responses of each species to future climate change is different and depends on various factors.

Although substantial studies are available as regards the abundance, richness and composition of freshwater fish along altitudinal slops, the impact of human factors such as dam construction are rarely considered. In this study, the effects of the environmental and human factors on longitudinal patterns of fish faunal changes, species richness and fish abundance from upstream to downstream in the southern profile of the central Alborz Protected Area were examined using Redundancy Analysis (RDA) and Generalized Linear Models (GLM). The Karaj River was divided into three zones based on habitat structure, physicochemical variables and species composition. The results indicate that chemical variables can be more effective in some conditions including small changes in habitat structure and physical variables along the altitudinal slope and can be a justification for the abundance, richness and composition of species. Typically, in highly polluted rivers, chemical agents can be a good explanation for the presence or absence of species. Human disturbances, such as dams, change the expected distribution patterns of fish along the altitudinal slope by decreasing outlet water temperature and also creating homogeneous and simple habitats. Therefore, the implementation of conservation programs should be a priority for the Karaj River fishes, especially in the middle areas which are affected by these threats.

The Eurasian Otter (Lutra lutra) is one of the mammals of the inland waters of Iran. This species is at the top of the food chain and at the risk of extinction. Eurasian Otter aquatic habitats are very vulnerable to man-made changes. So that, this species is in the near threatend (NT) category of the IUCN Red List. This study aimed at habitat quality evaluation for the Eurasian Otter in Markazi Province by using MCDA. In this regard, we used Analytical Network Process (ANP) method by using Super Decisions software, with 4 alternative, 4 criteria and 8 sub-criteria. The results showed that criteria of Economic and Social (0.33) and Biological (0.25) and sub-criteria of Local Conflict (0.18) and IRWQI (0.16) and Food availability(0.15) had the highest weight. Moreover Al-Ghadir Dam in Saveh and Ghar-Chai River (0.42) had the highest weight. Therefore, there is a need to preparation and implementation of extensive improvement and restoration program for the Eurasian Otter habitat in the Markazi Province especially the Shara River.

Damage due to thermal stress in the testicles is one of the causes of infertility in men and most of the mammals. Bioactive peptides have potent antioxidant activity against free radicals and reactive oxygen species. In this study, animals were randomly categorized into 6 groups; group 1 served as a control(22 ◦ C), group 2 was a bioactive peptide(10 mg kg-1 day, oral gavage, respectively) , group 3 was a heat-stressed (43 ◦ C), groups 4,5 and 6 were heat-stressed(43 ◦ C) along with bioactive peptides (5, 10 and 20 mg kg-1 day, oral gavage, respectively). After treatment (45 days), the testes were separated for histological and biochemical studies. Histopathological analysis revealed severe testicular damage following heat stress induction. Heat stress increased nitric oxide significantly(P 0/05). In the heat-stressed rats treated with 5 and 10 mg / kg bioactive peptide, no improvement was observed. Treatment of animals with 20 mg / kg showed positive effects on spermatogenesis and seminiferous tubules structure. The results of nitric oxide analysis showed a decrease in this biochemical factor following peptide treatment at a dose of 20 mg / kg(P 0/05). The results of this study showed the antioxidant effects of sardine-derived bioactive peptide on tissue and biochemical markers of testicular tissue.