EXPERIMENTAL ANIMAL BIOLOGY
Year:2015 | Volume:4 | Issue:1 (13)|Papers Count:9

Increase in the use of nano zinc oxide in medicine, manufacturing cosmetic products and research, have raised the questions about their toxicity. Zinc has direct role in growth, maturation and ovulation through influence on production of estradiol and progesterone. In this study the effects of nano zinc oxide on oogenesis of adult NMRI mouse strain have been investigated. The adult female mice were randomly divided into six groups, including control, sham and four experimental groups. Experimental groups were injected nano-ZnO (50-100-150-300 mg/kgbw) Intraperito-neally, respectively for 3 days. After 7 day, histological changes of ovaries were studied. Data indicated increase of numbers of Graafian follicles and corpora lutea in 100 and 150 mg/kg bw doses. Increase in estradiol and progestron levels with increase on dose was observed. Data indicated increase of numbers of atretic follicles with decreased body weight in higher doses. Results indicated oogenesis under 100 and 150 doses nano-Zno has improved with enhancing the number of Graafian follicles and corpora lutea, and decrease of body weight and increase of number of atretic follicles under higher doses. The results also indicated that nano-Zno has toxic effects on reproductive organs in female animal.

Background & aim: Recent increase of hormonal disorders in human may be correlated to the increased exposure to electromagnetic fields produced by various instruments, including cell phones. Thyroid gland is one of the organs most likely to be exposed to cell phone radiation. Whereas garlic is known as reducing risk factors for various diseases. The aim of this study is to assess the adverse effects of cell phone radiation along with the protective effects of garlic on thyroid tissue.5 groups of rats (n=8) were used: control, sham (exposed to 900 MHz wavelength), experimental1 (receiving 400 garlic extract), experimental2 (receiving 200 garlic extract and microwaves) and experimental3 (receiving 400 garlic extract and microwaves). After a month, Thyroid glands were removed and their probable histological changes were studied. Histological examination of thyroid revealed a reduction in the number of cubic cells and disorder among them, as well as a reduction in the amount of follicular fluid and follicular diameter in groups exposed to radiation and received garlic extract. As a result, exposure to radiation can cause damage to the thyroid gland, and garlic consumption are not always beneficial in reducing deleterious effects of cell phones.

Different factors such as the quality of ova and sperm are involved in propagation process. Mobility percentage, pH, mobility duration, compaction and osmolarity of sperm which affect the quality of sperm were tested in this research. This study was carried out in April 2011 in Shahid Ansari Bony Fishes Propagation and Rearing Center. According to the results, mean and standard deviation of ions in 3 and 4 years old fish were (329.6±11.9) and (343.4±11.9) osmolarity, (47.2±7.4 and 44.5±2.99) spermatocrit, (60.5±12) and (66.3±6.1) mobility duration, (80±6.7) and (83.5±3.9) mobility percentage, (17828750±3199657.8) and (18000000±2090454.5) compaction of sperm and 7.79±0.51 and 7.61±0.26 pH of sperm. The correlation between osmolality, mobility percentage, mobility duration, and compaction of sperm with parameters of artificial propagation efficiency (fertilization percentage and hatching rate) was investigated positive and direct (p<0.05).

In respect to nano-technological studies and physiological and biochemical lesions of these materials on aquatic animals, in this study we examine the toxicity effects of nano-zinc oxide (ZnO NPs) on hematological indices of common carp (Cyprinus carpio). LC50 of nano zinc oxide was determined according to the mortality at 24, 48, 72 and 96 hours, respectively. During separate experiment based on the LC50 levels, hematological parameters were studied with induction of the sub-lethal concentrations of nano zinc oxide. In this study, lethal toxicity concentration of nano-ZnO (LC50) for common carp was 3.120 ± 0.23 ppm. when the fish were exposed to sub lethal concentrations (50% of LC50) for 7days, the results showed that the nano-particles causes various changes in the blood parameters of the fish that these changes was affected by the nano-particles in blood indices by reducing the level of red blood cells (RBC), Hemoglobin, Hematocrit and increase in white blood cells (WBC) (P<0.05). In comparison of fish exposed to sub-lethal concentrations of the nano-particles compared to the control group MCHC showed a significant increase (P<0.05)but during experiment MCV and MCH didn’t show significant changes (P>0.05) in the exposed nano-ZnO. The results of this study showed that the sub-lethal toxicity of nano-particles could have a negative impact on hematological indices of Common carp, so we should prevent the entrance of such substances to the aquatic ecosystems.

900 rainbow trout (mean weight 25 gr) were obtained from a local fish farm in Urmia city and After acclimatization for 10 days, the fish were randomly divided into four groups (with three replication) and fed for 8 weeks with 0 (control), 2.5, 5 and 10 g chitosan/kg feed, respectively. Finally treatments were fed the control diet (without any chitosan) for another 3 weeks. Body weight, Total Length, Food Conversion Rate, Special Growth Rate, Condition Factor and Daily weight gain were determined every two week and at the end of the trial. Data were analyzed using SPSS ver.20. Results depicted no positive effects of chitosan on growth and nutritional parameters of rainbow trout, however, treatment four considerably (10 g chitosan/kg feed) inhibited live weight gain, total length increment and deteriorated food conversion rate (FCR) and specific growth rate (SGR) in comparison to control group and third treatment (5 g chitosan/kg feed).

The Syrphidae family (Known as hover flies or flower flies) is one of the largest families of Diptera with almost 6000 species. Adult flies feed on nectar and pollen of flowers and they are crucial agent in pollinating process. The larvae of many species of Syrphidae are predators of Aphids and play an important role in biological control of pests. In the following faunestic investigation, some ecological indices of Syrphidae family was carried out in Torbat-e Heydarie, Roshtkhar & Khaf cities (Razavi Khorasan Province) during 2010-2011and the most dominant species has been identified in each station of the study area. Adult species were collected randomly with entomological net and transferred to animal biosystematics lab in Shahid Beheshti University. The specimens have been identified by valid identification keys. After identification of species in 987 specimens, they have been sent to prof. Barkalov from institute of animal systematics and ecology, Siberian, Russia to confirm the obtain results and specimens were stored in the insect museum of bioscience faculty of Shahid Beheshti University. After survey of Iranian Syrphidae checklist, three species; Eumerus ornatus, Pipizella virens, Platycheirus fulviventris are new recorded from Razavi Khorasan Province. Two genus Pipizella and Platycheirus, are added to genus reported ofRazavi Province’s fauna. So far, the report of Platycheirus fulviventris from Guilan Province, Pipizella virens from north of Iran and Eumerus ornatus from Damavand city show that wider the range extension of this species in Iran.

Effects of stress due to transportation on the common carp (Cyprinus carpio) broodstock from ponds to the hatcheries in three intervals include immediately after the catching, 2 hours for transfer and 24 hours after transportation on changes in levels of cortisol, glucose, sex steroids (testosterone and estradiol) and blood factors were analyzed with sampling from 30 broodstock. Results showed that cortisol levels rose quickly after the catching (625 ng per ml) and significantly decreased after 24 hours (409 ng per ml) (P<0.05). Over time, the trend of the glucose variations was increased, however, no significant differences were observed at different times (from 81.7 to 98.5 g per dL) (P>0.05). Testosterone and estradiol levels were significantly different among the three intervals, in which the highest values were observed after the catching and significantly decreased with time (P<0.05). The amounts of red blood cells, hemoglobin, hematocrit, mean corpuscular volume, mean hemoglobin and mean cell hemoglobin concentration were significantly different between after the catching and other treatments (P<0.05), which may be affected by the stress caused by fishing. Levels of white blood cells, lymphocytes, monocytes, eosinophils and neutrophils showed no significant differences among treatments (P>0.05). Also, 24-hour maintenance of breeder’s improved the blood parameters. Based on the results, the transportation of common carp broodstock had negative effects on cortisol, steroid hormones and some blood parameters (erythrocyte and hemoglobin values), thereby it is necessary to the maintenance of broodstock (even in the short-term transfer) in hatcheries ponds.

At the present study effects of salinity were studied on growth and feeding performance, survival rate and blood biochemical parameters of pre on-growing rainbow trout (Oncorhynchus mykiss) with initial weight 93.22±4.11 g for 60 days. After adaptation for 10 days to water salinity, 450 fish were distributed in 5 treatments and 3 replicates according to completely randomized design. Before adaptation to water salinity and 1, 10, 25 and 50 days after introduction to different salinity (10, 20, 30 and 40 ppt), growth and feeding parameters and some blood biochemical parameters were investigated. According to the obtained results from this study, salinities up to and including 20 ppt significantly decreased growth and feeding parameters including daily growth rate, specific growth rate, feed conversion efficiency between salinity groups and control group (P<0.05) and higher salinities (30 and 40 ppt), caused gregarious mortality. During the experiment, blood biochemistry parameters including osmolality, chlorine, sugar, cortisol, tri-iodo thyronin (T3), and Tetra–iodo– thyronin (T4) significantly increased with increasing in water salinity (P<0.05). Overall, the obtained results indicated that rainbow trout with initial weighing 90 g could be cultured successfully in water with salinity up to 20 ppt, although fish growth rate is lower than that in the fresh water.

Balantidium coliis a ciliate intestinal protozoan with a wide host range in vertebrates, e.g. pigs, cattle, chimpanzees, and more rarely, dogs, cats, sheep, horses, and camels. This parasite causes clinical manifestation from asymptomatic to serious dysenteric forms. A total of 200 cattle were randomly selected from traditional farms of Darab city for a period of six month from January 2012 to July 2013. Feacal samples were prepared directly from rectum of these cattle. These samples were transferred to laboratory and were examined for the detection of Balantidium coli after concentration with formal-ether method and trichorme staining. The prevalence of Balantidium coliin the studied samples was 41.5%. The infection rate ofBalantidim coli among female and male cattle was 57 (43.2%) and 26 (38.2%) respectively. The highest and lowest prevalence ofBalantidium coli was in more than 3 years old cattle (47.6%) and 1 to 3 years old cattle (25.6%) respectively. There was statistical significant difference between prevalence and age groups (P<0.05). Out of examined samples 12 (6%) were positive for trophozoite, 48 (24%) for cyst and 23 (11.5%) for (cyst & trophozoite). Finally present study revealed that the cattle of Darab city were infected byBalantidium coli. Because of zoonotic important of this protozoan parasite, the measures should be taken to control and prevent this parasite.