Assessment of maximum sustainable yield of <i>Acanthopagrus berda</i> from Pakistani marine waters by applying surplus production models

1410-1416Picnic Sea bream (Acanthopagrus berda) fishery in the Northern Arabian Sea from Pakistani marine waters was analyzed using catch and effort data (1991-2008). Maximum, minimum and average catch was recorded as 1088 mt in 1999, 586 mt in 1991 and 828 mt year-1 respectively. MSY (Maximum sustainable yield) and other key fish population parameters of K (carrying capacity), q (catchability coefficient), r (intrinsic population growth rate) and CV (coefficient variation) values of the calculated MSY were estimated by CEDA (catch and effort data analysis) and ASPIC (a surplus production model incorporating covariates) computer software packages. The fishing mortality at maximum sustainable yield FMSY = 0.114 from logistic model and FMSY= 0.057 from Fox model was estimated by ASPIC. The stock biomass given MSY BMSY = 11990 (CV= 0.083) from Fox model and MSY BMSY = 13630 (CV= 0.037) was estimated in ASPIC. In CEDA the initial proportion (IP) of 0.5 was used, because starting catch was approximately 50% of the maximum catch. The estimated results of MSY using CEDA with three surplus production models Fox, Schaefer and Pella Tomlinson under three error assumptions of Normal, Log-Normal and Gamma were about 620-800 mt, which was lower than the catch of 897 mt in 2008, indicating that the A. berda fishery in the marine waters of Pakistan has been overexploited, therefore it is suggested that measures should be taken to reduce fishing effort for the rational exploitation of the fishery

Growth and mortality parameters of Indian squid Uroteuthis (Photololigo) duvaucelii (D'Orbigny,1835) from Pakistani waters(Arabian Sea) based on length frequency data.

1598-1603Present study was carried out to understand the Growth and Mortality parameters of commercially important Indian Squid Uroteuthis Duvauceli (D’ Orbigny.1985) based on length frequency data from Pakistani waters. The pooled n=1138 pair length-weight data of both sexes combined were used to calculate the length weight relationship as: W=0.278*L2.122 (R2=0.9520) length frequency data n=10008 were used to estimate VBGF growth parameters as =26.25(ML-cm) and K= 0.270 year-1 with goodness of fit model were estimated at Rn=0.335. The t0 value was calculated at t0=-0.442. Length converted catch curve analysis gave a Z value of 1.14 year-1. Natural mortality (M) obtained from Srinath’s method using empirical formula M = 0.4603+1.4753K, M=0.853 year-1. Fishing mortality was calculated as F=Z-M = 0.287 year and the exploitation rate (E) was calculated from F/Z = 0.251 year because the exploitation rate in present study is lower than 0.5

<span style="font-size:15.0pt;line-height:115%;font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";mso-bidi-font-family:"Times New Roman"; mso-ansi-language:EN-US;mso-fareast-language:EN-US;mso-bidi-language:AR-SA" lang="EN-US">Estimation of growth, mortality and exploitation of <span style="font-size:15.0pt;line-height:115%;font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";mso-bidi-font-family:"Times New Roman"; mso-ansi-language:EN-GB;mso-fareast-language:EN-US;mso-bidi-language:AR-SA" lang="EN-GB">lesser tiger toothed croaker <i style="mso-bidi-font-style:normal"><span style="font-size:15.0pt;line-height:115%;font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";mso-bidi-font-family:"Times New Roman"; mso-ansi-language:EN-US;mso-fareast-language:EN-US;mso-bidi-language:AR-SA" lang="EN-US">Otolithes cuvieri</span></i><span style="font-size:15.0pt;line-height:115%; font-family:"Times New Roman";mso-fareast-font-family:"Times New Roman"; mso-bidi-font-family:"Times New Roman";mso-ansi-language:EN-US;mso-fareast-language: EN-US;mso-bidi-language:AR-SA" lang="EN-US"> (Trewavas. 1974)<i style="mso-bidi-font-style: normal"> </i><span style="font-size:15.0pt;line-height:115%; font-family:"Times New Roman";mso-fareast-font-family:"Times New Roman"; mso-bidi-font-family:"Times New Roman";mso-ansi-language:EN-GB;mso-fareast-language: EN-US;mso-bidi-language:AR-SA" lang="EN-GB">in Pakistan</span></span></span></span>

63-68Four demersal trawl surveys were carried out in Pakistani marine waters in 2009-2010.  Length frequency data of 3219 individuals were used to estimate growth, mortality and exploitation, whereas data of 671 individuals were used to estimate length weight relationship in Otolithes cuvieri (Trewavas, 1974).  Length ranges from 3 - 35cm and weight ranges from 1 - 208g.  Length weight relationship parameters were computed as a = 0.014, b = 2.870 and R2 = 0.952. Using the ELEFAN routine of the FiSAT computer package, the calculated von Bertalanffy growth function parameters were L∞= 36.75cm, K= 0.300/year. Total mortality were computed using length-converted catch curve analysis at Z=1.26/year, whereas natural M=0.740/year and fishing mortality F=Z-M= 0.52/year were calculated. The exploitation ratios (E) were computed as Emax = 0.412, E10 = 0.355, E50 = 0.278. The yield per recruit analysis showed that when tc was 1, Fmax was calculated at 0.5 and F0.1 at 0.4. When biological reference point of Fopt was `M (0.740), current fishing mortality rate of 0.52 is smaller than the target biological reference point

Application of Bayesian surplus production model and traditional surplus production model on stock assessment of the southern Atlantic albacore (<i>Thunnus alalunga</i>)

922-928Bayesian surplus Production model (BSP) and traditional surplus Production models (TSP) were used to evaluate the southern Atlantic albacore (Thunnusalalunga) stock. Population parameterswere estimated using CEDA (catch-effort data analysis) and ASPIC (a surplus-production model incorporate covariates) computer software packages. Performance of the BSP model and TSP model were compared by a Bayesian information criterion (BIC). Maximum sustainable yield (MSY) from the TSP model and BSP model were used to verify the MSY estimations by International Commission for the Conservation of Atlantic Tunas (ICCAT). Catch of 2011 (24122 t) was higher than the MSY from BSP (21756t, 23408t), and the relative fishing mortality ratio (F2011/FMSY) of the stock was higher than 1.0, which shows thatthis stock over-exploited. Different harvest strategies were set to assess the risk for this stock, and these estimates were used topredict the biomass and catch in 2025 (B2025, C2025) and other five indexes (B2025 /BMSY, B2025 /K, P (B2025> B2012), P (B2025> BMSY), P (B2025MSY/4)). Evaluated biological reference points (BRPs) from Bayesian model were compared with the results from traditional modeling method on the southern Atlantic albacore (T. alalunga) stock, and results showed that the measures should be taken for the sustainable utilization of this fish stock, and the harvest rate of 0.15 seemed tobe the best management measures

Population dynamics of Randall’s threadfin bream <i>Nemipterus randalli </i> from Pakistani waters, Northern Arabian Sea

551-561The N. randalli fish data consist of 1141 pair of length weight relationship and 24312 length frequencies were measured during 2009 - 2010 survey. The maximum length and weight were 25 cm and 251 g, respectively. The length-weight relationship were a = 0.035, b = 2.744 and R2 = 0.972. The asymptotic length (L∞) and growth coefficient (K) were estimated to 26.25 cm and 0.320 year-1, respectively. The total mortality (Z) was 1.25 year-1. The natural mortality (M) was 0.863, hence the fishing mortality (F) was Z–M = 0.387 year-1 for N. randalli. The yield per recruit analysis indicated that when tc was assumed to be 2, Fmax was estimated at 1.3 and F0.1 at 1.3; while tc was assumed to be 1, Fmax was estimated at 1.1 and F0.1 at 0.95. Currently age at first capture is about 1 year and Fcurrent was 0.387, therefore, Fcurrent was smaller than F0.1 and Fmax. The results during present study indicate that current fishery stock is in sustainable state. However, it is suggested that take some management steps to maintain the stock of N. randalli in Pakistani waters, Northern Arabian Sea

1,2,3,4,6-Pentakis[-O-(3,4,5-trihydroxybenzoyl)]-α,β-D-glucopyranose (PGG) analogs: design, synthesis, anti-tumor and anti-oxidant activities

International audience1,2,3,4,6-Pentakis[-O-(3,4,5-trihydroxybenzoyl)]-α,β-D-glucopyranose (PGG) 12 has been reported for its antioxidant activities, where the free OH groups in PGG seem to be critical for activities. To explore PGG-based compounds as chemotherapeutic agents and to analyze the contribution of specific OH groups in PGG for anti-cancer activities, we designed and synthesized a series of 27 benzoic and cinnamic acid analogs of PGG. These analogs were tested for cytotoxicities against two human lung (A549 and H1299) and two human colon (HCT116 and HT29) cancer cell lines. Compound 12 (PGG) had highest cytotoxicities against HCT116 and A549 cells with IC50 of 1.61 µM and 3.02 µM, respectively. In contrast, the compound 16 (1,2,3,4,6-pentakis[-O-(4-hydroxy-3-methoxybenzoyl)]-α,β-D-glucopyranose, PVG) was most effective at killing HT29 and H1299 cells with IC50 of 1.76 µM and 3.65 µM, respectively, indicating the mutual contribution of m-methoxy and p-hydroxy groups to the observed cytotoxicities. Moreover, cinnamic acid analogs were less active than the benzoic acid analogs evidenced by higher IC50 values. Furthermore, in cinnamic acid analogs the hydrogenation of double bond to saturated 2-C side chain enhance the cytotoxicities in all four cell lines. Compounds also possess good anti-oxidant and reducing activities. Compound 12 and 26 show the highest antioxidant and reducing activities