10 research outputs found
The life cycle of green tiger prawn in the northern part of the Iranian water, Persian Gulf Phase 1: the identification of migration route and determination of the spawning areas and nursery grounds
Shrimp fisheries in the Persian Gulf have a long history. Since 1960 trawl fishery for Penaeid shrimp developed in the middle part of the northern coasts of the Persian Gulf (Bushehr waters). From 1998 to 2004 landing of shrimp have fluctuated between 480t and 2700t per year. The major species of penaeid shrimp (more than 80 percent) in the Persian Gulf and Bushehr waters is Penaeus semisulcatus. More than 2000 vessels and 33000 fishermen in Bushehr area were involving of shrimp catch (August and September) in study area in the recent decade. This species has an economical important role in the region. The present study was carried out in Bushehr coastal waters from 2003-2005. This study are described the bio-dynamic and life history of Penaeus semisulcatus in Bushehr area. Monthly samples of shrimp were collected by R/V LavarII from January 2003 to March 2004 for 15 months in 50 fixed stations. The carapace length frequency data were used to estimate the growth, mortality and exploitation rates by FiSAT program for males and females. The Von Bertalanffy growth parameters were estimated as K = 1.6 Year-1 and 2.2 Year-1 and L = 38mm and 50.4mm for male and female respectively. The results of mortality rates for males are Z = 6.4 per year F=4.3 per year and M = 2.11 per year. These results for female are Z = 8.2 per year, F=5.8 per year and M 2.41 per year. The exploitation rates for male and female are E=0.67 and E = 0.70 respectively. Relatively high values of total mortalities and exploitation rates were obtained which indicate that this species is overexploited. The maximum age was calculated 15 months for females and 18 months for males. Gonad maturity results were shown, the major spawning periods of green tiger prawn in the study area is in winter and early of spring and also there is a minor peak in autumn. Therefore two peaks of spawning were happened during this study. These periods are the main rainy seasons in the Bushehr area. The size at 50 percent mature (L50%) is 40.6mm and less than 5% of females were smaller than 24mm CL. Mature shrimps were aggregated in 20-30m depth of middle and southern part of study area. Imam Hassan, Genaveh and Helleh areas were the most important spawning grounds in Bushehr waters. The sex ration (male/female) of 0.84 was found during study period. This ratio was calculated in different months and the number of females were increased in spawning months. The number of 2571 shrimp were tagged and released by a green color polyethylene steamer tag during 15 months of survey and also before shrimping season (June and July) in 2005. The recaptures were done in two shrimp seasons in August and September 2004 and 2005 and 68 tagged shrimp recaptured that 4 recaptures were omitted due to inconsistencies information. Maximum recapture depths were 16-20m and 26-30m for males and females respectively. The majority of shrimp had a speeds of less than 2 Km/day, but maximum speed was recorded 3-4 Km/day in males and 2 Km/day in females. Only 10 percent of shrimp moved more than 50Km in study area and majority of shrimps, about 70 percent, were recaptured within 20Km of released area. The maximum recorded distance was 127Km after 95 days liberty in a female shrimp, but another female shrimp had only 20Km movement after 381 days and it was the maximum time between release and recaptured date. Tagged shrimp mostly moved to the northern part (Bahrekan area) of study area and recaptured shrimps pattern described stronger movement to the deeper waters. In the shallow waters of study area, sampling of juveniles of P. semisulcatus was carried out from July 2003 to March 2005. The survey was done after spawning months of this species and sampling were carried out in July, November and December 2003 and January, February, April, June, July 2004 and February and March 2005. Some stations in less than 10m depths were trawled by a small boat, equipped with a small beam trawl and the prawns (P. semisulcatus) less than 15mm carapace length were collected as juvenile. In this study 748 individuals shrimp were collected during study period. These juveniles were observed in July and November 2003 and April and June 2004. The carapace length of juveniles ranged from 3mm to 15mm and minimum of mean of carapace length were 4.5mm in November and maximum 9.6mm in July. The juveniles were observed around southern part (Mottaf) and middle part (Helaileh) of vegetated sites. A few juveniles were observed in non-vegetated areas. In the nursery grounds 47% of marine organisms were included other species that Sparidae, Platycephalidae, crabs, shells and other penaeid shrimp species such as Metapenaeus af inis and M. stebbingi were observed in nursery ground of green tiger prawn. Very few juveniles were caught during the colder months and seasonal abundance of juveniles was observed in the warmer months. Present study was shown that mature shrimp are dominant from December till March and juvenile stages were mostly observed in April to July. Spawning was occurred through the year, with two peaks minor in autumn and major in winter and spring. Fishing activity should be controlled in spawning and nursery ground of shrimp
A Case Report of Malignant Peripheral Nerve Sheath Tumor of the Breast
BACKGROUND AND OBJECTIVE: Breast sarcomas may be primary or secondary. Primary sarcoma of the breast is one of the extremely rare cases of breast malignancies whose possibility of occurrence is estimated to be 0.5 of all types of breast cancers and less than 5 of the all sarcomas .In this study, we present a woman with a malignant peripheral nerve sheath tumor in the brest. CASE REPORT: A 40-year old woman with a painless palpable mass in the right breast refered to imam khomeini hospital of one year ago. According to mammography and cytology and with the possibility of breast cancer patient undergoing surgery and the mass was removed. Histopathology feature and positive immunohistochemical markers such as S100 and vimentin confirmed malignant peripheral nerve sheath tumor of the breast (Triton type).Patient after mastectomy , radiation and chemotherapy regimen received and now, after 12 months no recurrence or metastasis has been seen. CONCLUSION: In breast cancer tumors, early diagnosis and appropriate therapeutic such as surgery , radiotherapy and chemotherapy are recommended to incrase overall survival and improve their quality of life
Monitoring green tiger prawn stock in Bushehr Province waters
The results of 30 months of trawl sampling on P. semisulcatus, De Hann 1848, obtained through operational phase of MONITORING GREEN TIGER PRAWN RESOURCES project, along with results of another available 28 months of the data of the same structure prior to this, has formed an invaluable time series of data as a proper basis for the further analysis. The survey area is located at North-west of the Persian Gulf from Bahrekan to Dayer waters. The ultimate goal of this study is to come to a better understanding of behavioral pattern of Green Tiger Prawn in its exploited phase after recruitment to the fishery. In this study, the confirmation of the life cycle of P. semisulcatus, to the general life pattern of Penaeidae shrimps was observed. Of the peculiarities of this pattern are the yearly bi-modal spawning and two corresponding peaks of recruitment. There exist two spring and autumn generations, which the major spawning in autumn produces the main recruitment in summer and the autumn generations stem from spring spawning. The spatial and temporal distribution of shrimp is highly variable by month and year. Depending on the year, higher shrimp densities are often found in early summer between Lavar and Rostami and/or Rostami to Bushehr and extend north and south in August. This result can be used in better design of sampling scheme for nursery studies. The main recruitment, which the fishery is depended upon, is in July to August and a second one occurs December-February. The timing and strength of both recruitments vary inter-annually. The proportion of prerecruits in southern area is always higher and the modes more prolonged than in northern area. The period of major recruitment starts earlier and lasts longer in the south than the north. A consistent pattern is not seen for the secondary recruitment, which, usually occurs in December-January. It is hypothesized that 1- the secondary recruitment might occur in Kuwait and/or Saudi Arabia waters, 2- insufficient number of spawners in spring or 3- high mortality in summer could cause the weakness of secondary recruitment. The spatial distribution of the mature female shrimps in spawning months indicates that the northern part of study area is an aggregation ground. It is also found that this aggregation grounds are close to two main fresh water sources (Helleh and Mond rivers), and these phenomena can be somehow related. The average length at 50% maturity varies inter- annually and is estimated to be 15.3 Cm. Length-frequency distribution of shrimps by sex reveals 1 to 3 modes depending on the month and year. In southern part a more complicated and less consistent pattern of recruitment and growth between years was observed. There is multiple or/and continuous recruitment especially during summer months. The von Bertalanffy growth parameters were estimated. The Findings are used to design new sampling schemes to cover the whole life cycle of this species enabling one to explain the variations in their response to the environment and fishery. The results of this study, lead us in building appropriate assessment and management models