Reproductive biology of the common torpedo, Torpedo torpedo (Linnaeus, 1758) (Pisces, Torpedinidae) from the coast of Senegal (Eastern Tropical Atlantic)

Among the five species of genus Torpedo recorded from the coast of Senegal, the common torpedo, Torpedo torpedo is that most cornrnonly caught in the area. Adult males and fernales studied were over 300 mm and 310 mm total length (TL), respectively, with the largest male and the largest female recorded being 445 mm and 550 mm TL respectively. Size at birth was between 102 and 125 mm TL (mean 112.12 mm; s.e.m. 5.58). Weight of eggs ranged frorn 6.2 to 8.0 g (rnean: 7.07; s.e.m. 0.5). Gestation lasts longer, from 6 to 8 rnonths, than in the Mediterranean specimens. A calculated chernical balance of development based on rnean dry weights of the fully developed fetuses and ripe oocytes was 1.58 for T. torpedo. This value shows that this torpedinid is not a pure lecithotrophic species, and the role of the rnother during gestation is not negligible. The fecundity (s.1.) of T. torpedo ranges from 5 to 28 in Senegalese specimens as cornpared to 1 to 9 in Mediterranean specirnens. Male ernbryos and fully developed fetuses are more nurnerous than fernales. Among the free-living specimens, nurnber of males and fernales is practically the same. The cornrnon torpedos from the coast of Senegal are larger and the eggs are heavier than Mediterranean specirnens. Key words: Pisces, Torpedinidae, Torpedo torpedo, Reproductive biology, Senegal, Eastern Tropical Atlantic.Among the five species of genus Torpedo recorded from the coast of Senegal, the common torpedo, Torpedo torpedo is that most cornrnonly caught in the area. Adult males and fernales studied were over 300 mm and 310 mm total length (TL), respectively, with the largest male and the largest female recorded being 445 mm and 550 mm TL respectively. Size at birth was between 102 and 125 mm TL (mean 112.12 mm; s.e.m. 5.58). Weight of eggs ranged frorn 6.2 to 8.0 g (rnean: 7.07; s.e.m. 0.5). Gestation lasts longer, from 6 to 8 rnonths, than in the Mediterranean specimens. A calculated chernical balance of development based on rnean dry weights of the fully developed fetuses and ripe oocytes was 1.58 for T. torpedo. This value shows that this torpedinid is not a pure lecithotrophic species, and the role of the rnother during gestation is not negligible. The fecundity (s.1.) of T. torpedo ranges from 5 to 28 in Senegalese specimens as cornpared to 1 to 9 in Mediterranean specirnens. Male ernbryos and fully developed fetuses are more nurnerous than fernales. Among the free-living specimens, nurnber of males and fernales is practically the same. The cornrnon torpedos from the coast of Senegal are larger and the eggs are heavier than Mediterranean specirnens. Key words: Pisces, Torpedinidae, Torpedo torpedo, Reproductive biology, Senegal, Eastern Tropical Atlantic.Among the five species of genus Torpedo recorded from the coast of Senegal, the common torpedo, Torpedo torpedo is that most cornrnonly caught in the area. Adult males and fernales studied were over 300 mm and 310 mm total length (TL), respectively, with the largest male and the largest female recorded being 445 mm and 550 mm TL respectively. Size at birth was between 102 and 125 mm TL (mean 112.12 mm; s.e.m. 5.58). Weight of eggs ranged frorn 6.2 to 8.0 g (rnean: 7.07; s.e.m. 0.5). Gestation lasts longer, from 6 to 8 rnonths, than in the Mediterranean specimens. A calculated chernical balance of development based on rnean dry weights of the fully developed fetuses and ripe oocytes was 1.58 for T. torpedo. This value shows that this torpedinid is not a pure lecithotrophic species, and the role of the rnother during gestation is not negligible. The fecundity (s.1.) of T. torpedo ranges from 5 to 28 in Senegalese specimens as cornpared to 1 to 9 in Mediterranean specirnens. Male ernbryos and fully developed fetuses are more nurnerous than fernales. Among the free-living specimens, nurnber of males and fernales is practically the same. The cornrnon torpedos from the coast of Senegal are larger and the eggs are heavier than Mediterranean specirnens. Key words: Pisces, Torpedinidae, Torpedo torpedo, Reproductive biology, Senegal, Eastern Tropical Atlantic

Atypical characteristics in the longnosed skate Dipturus oxyrinchus (Linnaeus, 1758) from the coast of Syria (Eastern Mediterranean)

EnA specimen of sharpnosed skate Dipturus oxyrinchus (Linnaeus, 1758) presenting snout and tail abnormalities was captured off the Syrian coast. It is an adult female with a shortened and rounded snout, lack of second dorsal fin and a reduced and rounded caudal fin. This abnormal specimen is described in the present note, and it appears that both snout and tail abnormalities did not affect their development and they reached similar parameters and swimming activities than the normal ones

Occurrence of an Intersexual Blacktip Shark in the Northern Gulf of Mexico, with Notes on the Standardization of Classifications for This Condition in Elasmobranchs

An intersexual Blacktip Shark Carcharhinus limbatus with a testis, immature female reproductive tracts (embedded), and claspers was caught in the Gulf of Mexico. Histology of the single gonad revealed that all stages of spermatogenesis were occurring; however, the absence of ovaries and a male duct system suggests that neither sex would have been functional in this individual. Intersexuality has been reported in 17 families and 36 species of elasmobranchs. The degree to which the different sexes are present in a given individual is often difficult to categorize by normal hermaphroditic standards, as this is typically an anomalous presentation in elasmobranchs. Therefore, this report provides three categories for classification (basic, incomplete, and complete intersexuality) to standardize terminology and allow for more precise comparisons to be made among elasmobranch examples. Basic intersexuals have gonadal tissue of only one sex and a combination of other male and female characters with neither or only one sex being complete. Incomplete intersexuals have gonadal tissue of both sexes and a combination of other male and female characters; however, neither or only one sex is complete. Complete intersexuals have claspers as well as gonadal tissue and tracts for both sexes. The majority of the reported intersexual elasmobranchs, including the shark described here, are basic intersexuals

Reproductive Strategy of the Giant Electric Ray in the Southern Gulf of California

The objective of the present study was to describe and characterize macroscopic and microscopic aspects of the reproductive biology of the Giant Electric Ray Narcine entemedor, a viviparous elasmobranch targeted by commercial fishers in Mexico. A total of 305 individual rays were captured (260 females, 45 males); all males were sexually mature. The median size at maturity for females was estimated to be 58.5 cm TL, the median size at pregnancy was 63.7 cm TL, and the median size at maternity was 66.2 cm TL. The range of ovarian follicles recorded per female was 1–69; the maximum ovarian fecundity of fully grown vitellogenic oocytes was 17, and uterine fecundity ranged from 1 to 24 embryos per female. The lengths of the oblong ovarian follicles varied significantly among months, and the largest ovarian follicles were found in July, August, and September. Median embryo size was largest in August, and the size at birth was between 12.4 and 14.5 cm TL. Histological evidence of secretions from the glandular tissue of the uterine villi indicate that this species probably has limited histotrophy as a reproductive mode. Vitellogenesis in the ovary occurred synchronously with gestation in the uterus. The Giant Electric Ray has a continuous annual reproductive cycle; a period of ovulation occurs between May and September and two peaks of parturition, one in January and one in August, occur, suggesting that embryonic diapause occurs in some individuals. These results provide useful information for the management of this important commercial species in Bahía de La Paz, Mexico, and will allow possible modification of the current Mexican regulations to enable better protection of this species

Obesity is associated with insulin resistance and components of the metabolic syndrome in Lebanese adolescents

adolescents has been reported to range between 18–42%, depending on country of origin, thus suggesting an ethnicbased association between obesity and MS. Aim: This study aims to investigate the magnitude of the association between obesity, insulin resistance and components of MS among adolescents in Lebanon. Subjects and methods: The sample included 263 adolescents at 4 th and 5 th Tanner stages of puberty (104 obese; 78 overweight; 81 normal weight). Anthropometric, biochemical and blood pressure measurements were performed. Body fat was assessed using dual-energy X-ray absorptiometry. Results: According to International Diabetes Federation criteria, MS was identified in 21.2 % of obese, 3.8 % of overweight and 1.2 % of normal weight subjects. The most common metabolic abnormalities among subjects having MS were elevated waist circumference (96.2%), low HDL (96.2%) and hypertriglyceridemia (73.1%). Insulin resistance was identified in all subjects having MS. Regression analyses showed that percentage body fat, waist circumference and BMI were similar in their ability to predict the MS in this age group. Conclusions: MSwas identified in asubstantial proportion of Lebanese obese adolescents, thus highlighting the importance of early screening for obesity-associated metabolic abnormalities and of developing successful multi-component interventions addressing adolescent obesity

Metabolic syndrome in overweight children from the city of Botucatu - São Paulo State - Brazil: agreement among six diagnostic criteria

<p>Abstract</p> <p>Background</p> <p>The metabolic syndrome has been described in children; however, a standard criterion has not been established for its diagnosis. Also, few studies have been conducted to specifically observe the possible existence of agreement among the existing diagnostic criteria. The purpose of the study is to evaluate agreement concerning prevalence rates of the metabolic syndrome diagnosed by six different criteria in overweight schoolchildren in the city of Botucatu - SP -Brazil.</p> <p>Methods</p> <p>This is a cross-sectional study on 128 overweight schoolchildren. Clinical examination included anthropometry, pubertal staging evaluation, and blood pressure. Triacylglycerol, glycemia, HDL-cholesterol, insulin levels, and HOMA-IR were determined. The Kappa index, the Mann-Whitney test and the chi-square test were used for statistical analysis.</p> <p>Results</p> <p>The prevalence of the metabolic syndrome varied from 10 to 16.5% according to different diagnostic criteria. Results were similar for boys and girls and pubertal stage. Great agreement was observed among the six different diagnostic criteria for the metabolic syndrome.</p> <p>Conclusions</p> <p>Different diagnostic criteria, when adopted for subjects with similar demographic characteristics, generate similar and compatible prevalence. Results suggest that it is possible to adopt any of the analyzed criteria, and the choice should be according to the components available for each situation.</p