Age and growth of flathead, Platycephalus indicus from the Persian Gulf (Bandar Abbas, Iran)

2014 ◽  
Vol 94 (5) ◽  
pp. 1063-1071 ◽  
Author(s):  
Dariush Mohammadikia ◽  
Ehsan Kamrani ◽  
Mohammad Reza Taherizadeh ◽  
Ayoub Soleymani ◽  
Ehsan Farokhi ◽  
...  

In a study of the age and growth of Platycephalus indicus, a total of 1106 fish were collected from May 2011 to March 2012 in the coastal waters of Iran, Persian Gulf. The ages of 279 specimens were determined by sectioned otoliths. The ages of the females were estimated to be between 0+ to 7+ , while the ages of the males were from 0+ to 4+. The von Bertalanffy growth curve was well suited to the age/total length data of males and females as follows: Lt = 43.40{1–exp[−0.45(t + 0.328)]} for males, and Lt = 63 {1–exp[−0.50(t + 0.30)]} for females. linf = 43.40, k = 0.45, t0 = −0.328 for females and linf = 63, k = 0.50, t0 = −0.30 for males. The estimated values of natural mortality (M) were M = 0.886 yr−1 for females and 0.736 yr−1 for males, and the estimated Z values were 1.43 yr−1 for females and 1.62 yr−1 for males. The mean value of the gonadosomatic index for males and females was 0.82 ± 0.25 and 2.48 ± 0.59, respectively, in each year. The mean values of the hepatosomatic index (HSI) were 0.89 ± 0.20 for males and 1.28 ± 0.16 for females. The highest HSI values for this location were observed in January, and the lowest were in April.

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Fábio Mineo Suzuki ◽  
Diego Azevedo Zoccal Garcia ◽  
Mário Luís Orsi

To study the reproductive dynamics of the mandi-beiçudo, Iheringichthys labrosus, in the Capivara Reservoir, Paranapanema River, Parana, Brazil, specimens were captured trimonthly from March 2001 to July 2004 at four sampling sites. The sex ratio showed a predominance of females in most of months sampled and the larger length classes. The majority of the individuals captured showed a standard length between 16 and 22 cm, with a maximal length of 27.5 cm. The size at first maturity was estimated to be 18.1 and 19.7 cm for females and males, respectively. Analysis of the temporal variation of the gonadosomatic index (GSI) and frequency of occurrence of gonadal maturation stages of males and females for the months sampled showed that I. labrosus reproduces during the whole year, with peak reproduction in November and December. There was a positive correlation between the mean values of GSI and variation in rainfall values, suggesting that this abiotic factor can influence the reproduction of this species. The mean absolute fecundity was 67274.5  16562.5 oocytes, and the mean relative fecundity was 350.6  186.3 oocytes per gram of total weight.


2020 ◽  
Vol 70 (2) ◽  
pp. 131-143
Author(s):  
Farideh Mohseni ◽  
Tooraj Valinassab ◽  
Ehsan Ramezani-Fard ◽  
S.M. Reza Fatemi ◽  
Mohammad Seddiq Mortazavi

Abstract Catfish are an important component of demersal fisheries in the Persian Gulf. This study describes reproductive aspects in the four common species of catfish, namely Netuma thalassina (Rüppell, 1837), Netuma bilineata (Valenciennes, 1840), Plicofollis dussumieri (Valenciennes, 1840), and Plicofollis layardi (Günther, 1866) collected from coastal areas of the Persian Gulf during spring and winter 2017. A total of 495 fishes were collected, including 151 N. thalassina, 12 N. bilineata, 212 P. dussumieri, and 120 P. layardi. The four species showed significant differences in total length as a measure of body size. Total length of these four species also differed significantly between the four seasons and between the sexes. Three species, i.e., N. thalassina, P. dussumieri, and P. layardi showed an overall female-biased sex ratio, while the sex ratio of N. bilineata did not differ from the expected equal proportions. The patterns of gonad development, gonadosomatic index, and hepatosomatic index of the four species showed that the breeding season of N. thalassina, P. dussumieri, and P. layardi was probably during winter. N. bilineata showed a different pattern; its breeding season is therefore expected to be spring. The size at first maturity of N. thalassina, P. dussumieri, N. bilineata, and P. layardi, was 44.99, 30.55, 29.60, and 27.01 cm, respectively. This study provides essential information for correct management during the reproductive cycle to maintain a healthy stock of these fishes.


Author(s):  
Hanieh Saeedi ◽  
Aria A. Ardalan

The occurrence of pinnotherid crab Arcotheres tivelae in the bivalve mollusc Amiantis umbonella was investigated for one year on the Bandar Abbas coast (Persian Gulf, Iran). Specimens of A. umbonella were collected monthly from two transects from April 2007 to March 2008 and were investigated for presence of the Arcotheres tivelae. Infestation frequency of A. tivelae was 9.18% in a sample of 893 clams. From a total of 89 specimens of crabs, only eight were male. They were observed in late February and early March, all of them but one in association with female crabs. There was no significant difference between the sexes of the infested clams that pea crabs choose as a host. The mean carapace width of the crab A. tivelae was 7.7 ± 1.7 mm and the mean length of the Amiantis umbonella was 39.84 ± 8.93 mm. Clams in the mid and low tidal zones were more infested. There was no significant relationship between clam length–crab width (R2 = 0.28). The mean fecundity of crabs was 2517 ± 864 eggs. Infection caused a reduction of flesh weight of clams. There was no significant correlation between the frequency of crabs' occurrence and the temporal variability of water temperature, salinity, dissolved oxygen and pH in different months. This study provides the first report of the distribution of pea crabs A. tivelae in A. umbonella, a new clam host record in Iran.


Author(s):  
Hanieh Saeedi ◽  
Shahrokh P. Raad ◽  
Aria A. Ardalan ◽  
Ehsan Kamrani ◽  
Bahram H. Kiabi

Solen dactylus is a razor clam distributed throughout the coast of the northern Persian Gulf. Study on biology of razor clams in this area is important for an essential management where these clams are overfished without any control. This study provides the first estimate of growth rate and an interpretation of the reproductive cycle of S. dactylus on the coast of the Persian Gulf (Bandar Abbas). In this study, 945 razor clams were collected from April 2007 to March 2008 along two transects of Golshahr coast in Bandar Abbas. Von Bertalanffy growth parameters for transects 1 and 2 ranged from 101–108 mm for asymptotic length (L∞), 0.27–0.28 year−1 for growth constant (k), and −0.99–0.94 for age at length zero (t0), respectively. Gonads were stained with haematoxylin and eosin and gametogenic stages were based on seven stages: (Stage 0) sexual rest; (Stage I) proliferation of gonad and start of gametogenesis; (Stage II) advanced gametogenesis; (Stage IIIA) ripeness; (Stage IIIB) start of spawning; (Stage IIIC) restoration; and (Stage IV) emission. The result showed that S. dactylus is a gonochoric clam and both males and females demonstrated synchronism in gonadal development. The gametogenic cycle began in late August and ended in late February. After several minor spawnings, plus a major one in January, the razor clams entered to the sexual rest stage in March.


2004 ◽  
Vol 35 (2) ◽  
pp. 119-137 ◽  
Author(s):  
S.D. Gurney ◽  
D.S.L. Lawrence

Seasonal variations in the stable isotopic composition of snow and meltwater were investigated in a sub-arctic, mountainous, but non-glacial, catchment at Okstindan in northern Norway based on analyses of δ18O and δD. Samples were collected during four field periods (August 1998; April 1999; June 1999 and August 1999) at three sites lying on an altitudinal transect (740–970 m a.s.l.). Snowpack data display an increase in the mean values of δ18O (increasing from a mean value of −13.51 to −11.49‰ between April and August), as well as a decrease in variability through the melt period. Comparison with a regional meteoric water line indicates that the slope of the δ18O–δD line for the snowpacks decreases over the same period, dropping from 7.49 to approximately 6.2.This change points to the role of evaporation in snowpack ablation and is confirmed by the vertical profile of deuterium excess. Snowpack seepage data, although limited, also suggest reduced values of δD, as might be associated with local evaporation during meltwater generation. In general, meltwaters were depleted in δ18O relative to the source snowpack at the peak of the melt (June), but later in the year (August) the difference between the two was not statistically significant. The diurnal pattern of isotopic composition indicates that the most depleted meltwaters coincide with the peak in temperature and, hence, meltwater production.


2021 ◽  
Vol 82 (1) ◽  
Author(s):  
Sana Sharifian ◽  
Vahid Malekzadeh ◽  
Ehsan Kamrani ◽  
Mohsen Safaie

Abstract Background Dotillid crabs are introduced as one common dwellers of sandy shores. We studied the ecology and growth of the sand bubbler crab Scopimera crabricauda Alcock, 1900, in the Persian Gulf, Iran. Crabs were sampled monthly by excavating nine quadrats at three intertidal levels during spring low tides from January 2016 to January 2017. Results Population data show unimodal size-frequency distributions in both sexes. The Von Bertalanffy function was calculated at CWt = 8.76 [1 − exp (− 0.56 (t + 0.39))], CWt = 7.90 [1 − exp (− 0.59 (t + 0.40))] and CWt = 9.35 [1 − exp (− 0.57 (t + 0.41))] for males, females, and both sexes, respectively. The life span appeared to be 5.35, 5.07, and 5.26 years for males, females, and both sexes, respectively. The cohorts were identified as two age continuous groups, with the mean model carapace width 5.39 and 7.11 mm for both sexes. The natural mortality (M) coefficients stood at 1.72 for males, 1.83 for females, and 1.76 years−1 for both sexes, respectively. The overall sex ratio (1:0.4) was significantly different from the expected 1:1 proportion with male-biased. Recruitment occurred with the highest number of annual pulse once a year during the summer. Conclusions The results, which show slow growth, emphasize the necessity of proper management for the survival of the stock of S. crabricauda on the Iranian coast of the Persian Gulf.


Author(s):  
Yuko Komuro ◽  
Yuji Ohta

Conventionally, the strength of toe plantar flexion (STPF) is measured in a seated position, in which not only the target toe joints but also the knee and particularly ankle joints, are usually restrained. We have developed an approach for the measurement of STPF which does not involve restraint and considers the interactions of adjacent joints of the lower extremities. This study aimed to evaluate this new approach and comparing with the seated approach. A thin, light-weight, rigid plate was attached to the sole of the foot in order to immobilize the toe area. Participants were 13 healthy young women (mean age: 24 ± 4 years). For measurement of STPF with the new approach, participants were instructed to stand, raise the device-wearing leg slightly, plantar flex the ankle, and push the sensor sheet with the toes to exert STPF. The sensor sheet of the F-scan II system was inserted between the foot sole and the plate. For measurement with the seated approach, participants were instructed to sit and push the sensor with the toes. They were required to maintain the hip, knee, and ankle joints at 90°. The mean values of maximum STPF of the 13 participants obtained with each approach were compared. There was no significant difference in mean value of maximum STPF when the two approaches were compared (new: 59 ± 23 N, seated: 47 ± 33 N). The coefficient of variation of maximum STPF was smaller for data obtained with the new approach (new: 39%, seated: 70%). Our simple approach enables measurement of STPF without the need for the restraints that are required for the conventional seated approach. These results suggest that the new approach is a valid method for measurement of STPF.


Ocean Science ◽  
2010 ◽  
Vol 6 (4) ◽  
pp. 887-900 ◽  
Author(s):  
M. Ezam ◽  
A. A. Bidokhti ◽  
A. H. Javid

Abstract. A three dimensional numerical model namely POM (Princeton Ocean Model) and observational data are used to study the Persian Gulf outflow structure and its spreading pathways during 1992. In the model, the monthly wind speed data were taken from ICOADS (International Comprehensive Ocean-Atmosphere Data Set) and the monthly SST (sea surface temperatures) were taken from AVHRR (Advanced Very High Resolution Radiometer) with the addition of monthly net shortwave radiations from NCEP (National Center for Environmental Prediction). The mean monthly precipitation rates from NCEP data and the calculated evaporation rates are used to impose the surface salinity fluxes. At the open boundaries the temperature and salinity were prescribed from the mean monthly climatological values from WOA05 (World Ocean Atlas 2005). Also the four major components of the tide were prescribed at the open boundaries. The results show that the outflow mainly originates from two branches at different depths in the Persian Gulf. The permanent branch exists during the whole year deeper than 40 m along the Gulf axis and originates from the inner parts of the Persian Gulf. The other seasonal branch forms in the vicinity of the shallow southern coasts due to high evaporation rates during winter. Near the Strait of Hormuz the two branches join and form the main outflow source water. The results of simulations reveal that during the winter the outflow boundary current mainly detaches from the coast well before Ras Al Hamra Cape, however during summer the outflow seems to follow the coast even after this Cape. This is due to a higher density of the colder outflow that leads to more sinking near the coast in winter. Thus, the outflow moves to a deeper depth of about 500 m (for which some explanations are given) while the main part detaches and spreads at a depth of about 300 m. However in summer it all moves at a depth of about 200–250 m. During winter, the deeper, stronger and wider outflow is more affected by the steep topography, leading to separation from the coast. While during summer, the weaker and shallower outflow is less influenced by bottom topography and so continues along the boundary.


2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 1079.1-1079
Author(s):  
I. Yoshii

Background:Boolean remission criteria is one most popular and stringent criteria in treating patient with rheumatoid arthritis (RA), because it may guarantees a stable clinical course after attaining remission.Objectives:Impact of time span from initiation to achieving Boolean remission on maintaining disease activity, daily activities, and quality of life after attaining Boolean remission was investigated from daily clinical practice data.Methods:685 patients with RA since August 2010 under the T2T strategy were treated. They were monitored for their TJC, SJC, PGA, EGA, CRP, and disease activity indices such as CDAI, SDAI, DAS28, and Boolean criteria at every visit. HAQ-DI score, pain score using visual analog scale (PS-VAS), and EQ-5D were also monitored, and the quality of life score (QOLS) calculated from EQ-5D was determined at every visit from the time of diagnosis (baseline).Of 685 patients, 465 patients had achieved Boolean remission >1 times, and were consecutively followed up for >3 years. These patients were enrolled in the study. Time span from the first visit to first Boolean remission was calculated. The relationship between the time span and each of background parameters, and the relationship between the time span and each of the mean values of the SDAI score, HAQ score, PS-VAS, SHS, and QOLS at the first Boolean remission and thereafter was evaluated statistically.Patients were subsequently divided into the G ≤ 6 and G > 6 groups based on the achievement of first Boolean remission within two groups: time span G ≤ 6 months and G > 6 months. The two groups were compared with regard to the SDAI score, HAQ score, PS-VAS, SHS, and QOLS at first visit and at the time of first Boolean remission, and the mean values of these parameters after remission were evaluated statistically. Moreover, changes of these parameters and the mean Boolean remission rate after the first remission, and SDAI remission rate at the first Boolean remission to thereafter were compared between the two groups statistically.Results:Out of 465 patients, females comprised 343 (73.7%), and the mean age was 67.8 years (range, from 21–95 years). The mean disease duration at first visit was 6.1 years (range, from 1 months–45 years). The mean follow up length was 88.1 months (range: 36–122 months; median: 85 months) and mean time span from the first visit to the first Boolean remission was 8.1 months. The mean SDAI score, HAQ score, PS-VAS, and the QOLS at first visit were 13.3, 0.467, 33.2, and 0.834, respectively. Among the study parameters, PS-VAS and QOLS were significantly correlated with the time span. For parameters at the first Boolean remission, HAQ-DI score, PS-VAS, and QOLS demonstrated significant correlation with the time span, whereas SDAI, HAQ-DI score, PS-VAS, SHS, and QOLS after the Boolean remission demonstrated significant correlation with the time span.The comparison between the G ≤ 6 and the G > 6 groups revealed that the disease duration, HAQ score, and PS-VAS at baseline in the G > 6 were significantly higher than that in the G ≤ 6 group, and QOLS in the G ≤ 6 group was significantly higher than that in the G > 6 group at baseline. Similarly, the HAQ score and PS-VAS at the first Boolean remission in the G > 6 group were significantly higher than that in the G ≤ 6 group, whereas QOLS in the G ≤ 6 group demonstrated no significant difference compared with that in the G > 6 group.The mean value of the SDAI score after the first Boolean remission in the G > 6 group was significantly higher than that in the G ≤ 6 group. Similarly, the SDAI score, HAQ score, and PS-VAS after the first Boolean remission in the G > 6 group were also significantly higher than those in the G ≤ 6 group, and the mean value of the QOLS in the G ≤ 6 group were significantly higher than that in the G > 6 group. The Boolean remission rate and SDAI remission rate after the first Boolean remission were significantly higher in the G ≤ 6 group than those in the G > 6 group.Conclusion:Attaining Boolean remission ≤ 6 months for RA has significant benefit for more stable disease control, that leads good maintenance of ADL.Disclosure of Interests:None declared


Nematology ◽  
2021 ◽  
pp. 1-22
Author(s):  
Azadeh Gharahkhani ◽  
Ebrahim Pourjam ◽  
Daniel Leduc ◽  
Majid Pedram

Summary The Desmodoridae is a diverse and widespread family of free-living nematodes. Here, we provide the first record of the group in the Persian Gulf and describe three new species: Metachromadoroides sinuspersici sp. n., Zalonema iranicum sp. n. and Z. supplementorum sp. n. Metachromadoroides sinuspersici sp. n. is characterised by finely annulated cuticle, short and stout cephalic sensilla, amphidial fovea on cuticular thickening, pharyngeal bulb well developed and partitioned into three sections, absence of precloacal supplements, and presence of 6-8 pairs of rounded postcloacal papillae. Zalonema iranicum sp. n. is characterised by papilliform subcephalic sensilla (best observed with SEM), convex cephalic capsule, large multispiral amphidial fovea with 4-5 turns in both males and females, buccal cavity with one ventrosublateral and two dorsal teeth and posterior body of males with lateral alae extending from the last third of the body to the cloacal aperture and ventral alae extending 1395-2250 μm anterior to the cloacal aperture, and no precloacal supplements. Zalonema supplementorum sp. n. is characterised by four subcephalic sensilla 1-2 μm long, multispiral amphidial fovea with three turns in both males and females, buccal cavity with one dorsal and two ventrosublateral teeth, males with lateral alae present on each side of body from posterior half of body to cloacal aperture, ventral alae extending 942-1257 μm anterior to cloacal aperture, strongly cuticularised spicules 41-43 μm long, and 12-16 precloacal supplements. Near full length SSU and partial D2-D3 LSU sequences are provided for M. sinuspersici sp. n. and Z. iranicum sp. n., and the COI sequence is provided for Z. iranicum. The SSU phylogeny suggests a close relationship between M. sinuspersici sp. n. and Metachromadora and Metachromadoroides species and the monophyly of Zalonema (after currently available data). The LSU phylogeny suggests an affinity between Metachromadoroides and Zalonema with Spirinia and Acanthopharynx, respectively.


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