JOURNAL OF BIOLOGY SCIENCE
Year:2008 | Volume:2 | Issue:1 (SERIES NO. 4)|Papers Count:9

Fungal infections may decrease the hatching rate of Salmonid eggs. In hatcheries center of Iran, Malachite green is still in use to control of fungus. However because of its teratogenicity, it is necessary to use other favorable chemicals such as Formalin. In this research Formalin concentrations of 1000 and 1500 m1/1, Malachite Green with usual concentration (1.5 mg/1) and natural control treatments were examined to evaluate the antifungal effects of the chemicals on Rainbow Trout eggs. Formalin and malachite Green treatments performed after 48 hours after fertilization in every other days until  4 days before hatch, each time for 15 minutes. The fungal infection was minimal in Malachite Green treatment and was significant different with other treatments (p£0/05). The  ratio of eyed eggs treated with 1500 m1/1 Formalin treatment was significantly higher than Malachite Green and control treatments ( p£0/05) but it was not significantly difference with 1000 m1/1 Formalin treatment (p>0/05) . The hatch rate in 1500 m1/1 Formalin treatments showed significant difference with other treatments (p£0/05). At last deformities rate have no significant difference in all treatments (p>0/05).

According to confirmations of commission on aquatic bioresources of the Caspian Sea and insist of convention on international trade in endangered species of wild fauna & flora (CITES), all Caspian littoral states assigned to participate in sturgeon stock assessment survey in order to study and determine the sturgeon stocks, their absolute abundance, percentage of catch composition and relative abundance of different sturgeon species. Following this confirmation, the experts of Iranian Fisheries Research organization and KaspNIRKh Institute, prepared the proposal & decided to apply trawl. In this regard, a common survey carried out during summer 2004 and 2005 with cooperation of Caspian littoral states in north, middle and southern parts of Caspian Sea (except Azerbaijan Republic) by trawling. The number of stations was 234 and 204 stations in 2004 and 2005, respectively. Selection of sampling stations in Iran was carried out through stratified random design and in Russia, KaspNIRKh Institute had stable stations. Two types of bottom trawls were used for sampling (9m trawl for depth under l0m and 24.7m trawl for above 10m depth). In 2004 summer survey, 1208 specimens captured which contained 889 Persian sturgeons, 234 Russian sturgeons and 58 stellate sturgeons, 14 Beluga and 3 Ship sturgeons. In 2005 summer survey totally 436 sturgeon captured which includes 341 Persian sturgeon, 57 Russian sturgeon and 30 Stellate sturgeon, 7 Beluga and 1 Ship sturgeon. Catch composition in 2004 summer survey comprised 74.42% Persian sturgeon, 19.37% Russian sturgeon, 4.8% stellate sturgeon, 1/16% Beluga and 0.25% Ship sturgeon. In 2005 summer survey, catch composition was 78.21% Persian sturgeon, 13.07% Russia sturgeon, 6.89% stellate sturgeon, 1.6% Beluga and 0.23% Ship sturgeon.

Rumen Microbial ecosystem mainly consists of bacteria, protozoa and fungi population and their main function in the rumen is fermenting consumed feedstuff. The objective of this experiment was determining the effect of complete elimination of protozoa, on rumen microbial protein supply. In this experiment four rumen fistulae and castrated male sheep and four rumen fistulae goats were used in a Latin square design. Four diets consist of: 1) all forage diet, 2) diet with 20% concentrate, 3) diet with 40% concentrate and 4) diet with 60% concentrate, performed in faunated and defaunated stages, respectively. Defaunating the rumen of sheep and goat was performed by two stage procedure of emptying and washing method. Determination of rumen microbial supply was calculated by measuring daily purine derivatives excreted via urine. This method is based on measurement of total uric acid, allantoine, xanthine and hypoxanthine excreted from urine. The results of this survey indicated that diets had no significant effect on microbial protein (MP) supply in rumen of both sheep and goat, but defaunation of sheep rumen increased MP synthesis (11.18 vs. 7.73 g/day) and elimination of protozoa form goat rumen increased MP supply, too (7.82 vs. 6.05 g/day), and there was a significant statistical difference between faunated and defaunated stages (p<0.05).

The Oshmak River is one of the most important rivers for agriculture in Guilan province; Tat has originated from south of Kochesfahan city and by crossing from Lashtnesha, Zibakenar City and west of Boojagh wetland, enter to Caspian Sea. This river transfers pesticides to Caspian Sea, for the rice paddy in its watershed. From this pesticide, Hinosan (Fungicide), Machete (Herbicide) and Diazinon (Insecticide) are used too in the last years as a pesticide in agriculture forms. Therefore, survey and measurement of these pesticides in the Oshmak River in from spring 2006- winter 2007 was necessary. Then, in 8 stations, we took sample and measured pesticides, seasonally. From station token 2 liter water and transfer to laboratory immediately. Then were measurement pesticide by Gc.mass. According to result mean ± SD of Hinosan was 1.27± 1.26 ppb (0.10-6.20ppb), Machete was 2.79±3.02 (0.50-12ppb) and Diazinon was 0.29±0.33 (0.10-1.10ppb) annually.

Environment stress may be abiotic or anthropogenic. Biotic factors such as insect and fungal diseases and weeds are responsible for losses representing less than 20% of the potential harvest of most species, abiotic factors including high irradiation chilling frost, drought, flooding, salinity and nutrient imbalances are responsible for most crop losses. Drought commonly being the most destructive factor. Some of these stress factors slowly and gradually affect plant growth conditions. Science plants are sessile organisms for stress avoidance; they need flexible organisms and have only limited mechanisms for stress avoidance. Author pogenic actives have caused air and soil pollution acid precipitation, soil degradation, uv-B radiation, climate change and etc. the present study has been undertaken to study how various abiotic stresses affect the metabolism of tea plant. Among the abiotic stresses, drought salinity, temperature been considered. Following the various treatment, leave were sampled and analyzed for phenolic compound, protein and prolin content. In the present investigation response to temperature stress (45, 50,55oc), phenol contents, decreased gradually whereas in all other two stresses there was an intial increase in phenol contents followed by a decrease. Proline content showed increased accumulation following the various stress. In temperature stress after 45°c, there was a decrease in proline content. Protein content on the other hand decreased flowing temperature stress, and in other stresses too there was a decrease flowing an initial increase. For statistically research was used of SPSS. In conclusion it might be standed that tea plants tolerate the various abiotic stresses to agreed degree by alterations in their metabolic pathway and shifting to production at metabolites most suitable to the plant for with sternding the stress.

One hundred Bacillus spp. were isolated from different soil samples of Guilan province including cattle and birds composts manure. Among the isolates, 60 Bacillus spp. were a-amylase producers in semiquantiative screening method. Amongst the amylase producers, Bacillus sp. BC18 showed the highest a-amylase activity according to quantitative screening method. The immobilization of Bacillus sp. BC18 cells was performed using various matrices, such as: calcium alginate, agar- agar and gelatin in order to compare a-amylase production with free cells. The enzyme production with immobilized cells in all of the three matrices reached a maximum level by 24 hours. Whereas the maximum enzyme production was observed by 48 hours in the case of free cells. All of the matrices were selected for repeated batch fermentation. Optimum level of the enzyme activity was maintained for 8 days using calcium alginate matrix. But it was maintained 5and 3 days using agar-agar and gelatin respectively. Calcium alginate was found to be an effective and suitable matrix for higher a-amylase productivity compare to the other matrices studied. Also, The influence of alginate concentration and initial cell loading (ICL) on the enzyme production with immobilized cells in calcium alginate were investigated. The production of a-amylase was improved significantly with increasing alginate concentration and reached a maximum enzyme yield at 30 g/l alginate concentration. Increasing ICL in the form of the number of beads could increase enzyme production. The results revealed that increasing the number of alginate beads up to 300 was accompanied by increased activity of a-amylase.

Polyhydroxyalkanoates (PHAs) polyesters, naturally produced by many species of microorganisms, are being considered as a replacement for conventional plastics. Unlike petroleum-derived plastics that take several decades to degrade, PHAs can be completely biodegraded within a year by a variety of microorganisms. This biodegradation results in carbon dioxide and water, which return to the environment. The aim of this study was isolation of betaketothiolase gene (bktB) from Ralstonia eutropha strain H16 which will be used for modification of biodegradable plastics properties. The gene bktB encodes an enzyme which controls a key step in biodegradable copolymers formation. Specific DNA primers were designed for isolation of bktB. Then its entire ORF was amplified by PCR using R. eutropha genomic DNA as template. Accuracy of gene isolation was initially confirmed by Nested PCR and then was revealed by sequencing. Because of positive physical properties of copolymers in industry such as stability, flexibility and biodegrability; the isolation of this gene could efficiently be used towards production of bioplastics with enhanced properties.

In this experiment the effect of using newly hatched Artemia and n-3HUFA enriched Artemia as starter food for rainbow trout larvae were investigated and compared with artificial food. Larvae with absorbed yolks sock having 92.2±3.3 mg initial weight were reared for 20 days using the following 4 different treatments with 3 replicate in 12 tanks: artificial food (control), newly hatched Artemia, enriched Artemia and mixed of 50% enriched Artemia and 50% artificial food. At the end of experiment, highest percentage of weight gain (104.4±9.4%) was observed in treatment 3(p< 0.05) and highest percent of survival (96.5±1.69 %) occurred with larvae reared using treatment 4 (p<0.05). So, using of unsaturated fatty acids in diet of rainbow trout larvae increases the weight gain and survival.