Sexual Maturity Of Females Research Articles

Age and reproduction of the finless porpoises, Neophocaena asiaeorientalis, in the Yellow Sea, Korea

A total of 116 finless porpoises, Neophocaena asiaeorientalis, were collected in the Yellow Sea off Korea. About 111 specimens were incidentally caught by stow nets on anchors from March to June 2010, and five were stranded in February 2011. Age was determined by counting dentinal growth layer groups (GLGs) in thin-sectioned teeth, and sexual maturity rating (SMR) was classified by investigating ovaries and testis macroscopically and microscopically. Immature females were ranged 1–4 years old and 92.6–141.2 cm in total body length (TBL), pubertal ones were all 5 years old and 125.4–136.0 cm, and mature ones ranged 5–19 years old and 131.6–155.2 cm. Age at attainment of sexual maturity of females was 4–5 years old. Parturition season estimated based on TBL of eight fetuses was from April to August with a peak in April to May. The first age at parturition was 5 years old. Among 62 males, immature males were 1–4 years old and 87.9–154.6 cm, pubertal ones were 3–5 years old and 121.5–134.5 cm, and mature ones were 4–19 years old and 125.3–229.0 cm. Males reached sexual maturity at 4–5 years old. Testicular mass and the diameters of seminiferous tubules were dramatically increased with SMR and regressed in testis of the individuals stranded in February. It suggested that male finless porpoises have aspermatogenic period between October and February. It is presumed that the breeding season would be May–September with a peak in May–June.

Structure of the Loggerhead Turtle Assemblage in Okinawan Waters Estimated from Variation in Body Size and Blood Profile

In order to estimate the structure of the loggerhead turtle assemblage in Okinawan waters, we measured the straight carapace length (SCL) and sexed 35 loggerhead turtles captured by set net between 2007 and 2011. Sexual maturity in females was determined on the basis of plasma triglyceride, cholesterol, total protein, and calcium concentrations. Of the 35 captured loggerhead turtles, 18 turtles were identified as males based on their elongated tails, while 16 turtles were identified as females in the process of vitellogenesis based on highly elevated blood plasma levels. Only one turtle with low plasma measurements was of indeterminate sex. We suggest that blood plasma measurements may serve as a useful indicator of female maturity. SCL means were 865 ± 48 mm (mean ± SD) for all turtles, 865±47 mm for males, and 871±52 mm for females; the turtle of unknown gender had an SCL of 791 mm. The loggerhead turtle assemblage in Okinawan waters was found to be larger in SCL and higher in the frequency of mature individuals than those in conspecific assemblages in other areas of Japanese waters so far studied. We suggest that the loggerhead turtles migrating to Okinawan waters are primarily in active reproductive states in preparation for mating and nesting.

Efficacy of calf:cow ratios for estimating calf production of arctic caribou

Caribou (Rangifer tarandus granti) calf:cow ratios (CCR) computed from composition counts obtained on arctic calving grounds are biased estimators of net calf production (NCP, the product of parturition rate and early calf survival) for sexually-mature females. Sexually-immature 2-year-old females, which are indistinguishable from sexually-mature females without calves, are included in the denominator, thereby biasing the calculated ratio low. This underestimate increases with the proportion of 2-year-old females in the population. We estimated the magnitude of this error with deterministic simulations under three scenarios of calf and yearling annual survival (respectively: low, 60 and 70%; medium, 70 and 80%; high, 80 and 90%) for five levels of unbiased NCP: 20, 40, 60, 80, and 100%. We assumed a survival rate of 90% for both 2-year-old and mature females. For each NCP, we computed numbers of 2-year-old females surviving annually and increased the denominator of CCR accordingly. We then calculated a series of hypothetical “observed” CCRs, which stabilized during the last 6 years of the simulations, and documented the degree to which each 6-year mean CCR differed from the corresponding NCP. For the three calf and yearling survival scenarios, proportional underestimates of NCP by CCR ranged 0.046–0.156, 0.058–0.187, and 0.071–0.216, respectively. Unfortunately, because parturition and survival rates are typically variable (i.e., age distribution is unstable), the magnitude of the error is not predictable without substantial supporting information. We recommend maintaining a sufficient sample of known-age radiocollared females in each herd and implementing a regular relocation schedule during the calving period to obtain unbiased estimates of both parturition rate and NCP.

Using osmotic pumps to deliver hormones to induce sexual maturation of female Japanese eels, Anguilla japonica

This study examines how the continuous administration of various hormones using an osmotic pump, a long-term sustained hormone release system, influences the induction of sexual maturation in females of the Japanese eel, Anguilla japonica. Human chorionic gonadotropin (hCG), salmon pituitary extract (SPE), and gonadotropin-releasing hormone analogue (GnRHa) were tested, and the consequent egg quality was evaluated. The implantation of osmotic pumps loaded with SPE induced vitellogenesis and increased the gonadosomatic index (GSI) at 39–110days. In comparison, pumps loaded with hCG inconsistently induced early vitellogenesis, while those loaded with GnRHa did not exhibit any stimulatory effect. Fewer eels attained full maturity when using the osmotic pump system compared with SPE-injected female eels. However, after the final treatment, the number of eels that ovulated and the time required for ovulation were similar for both the osmotic pump and injection groups. Moreover, more eggs were spawned in the SPE-loaded osmotic pump group than in the SPE-injected group. Egg quality was similar for both experimental groups. Therefore, the implantation of an osmotic pump loaded with SPE represents a reliable method for inducing vitellogenesis and obtaining ovulated eggs from sexually immature Japanese eels.

Sex steroid levels and expression patterns of estrogen receptor gene in the oyster Crassostrea angulata during reproductive cycle

Temporal variations in estradiol-17β (E2) and testosterone (T) levels from initiation to partially spent stages of Fujian oyster, Crassostrea angulata from China were investigated by enzyme-linked immunosorbent assay. E2 concentration varying between 95.97 and 280.98pg/g wet weight in the female gonads was higher than that in the male gonads (P<0.05), while T concentration ranging from 16.06 to 30.09pg/g wet weight in the male gonads was higher than that in the female gonads (P<0.05). Both steroids increased during sexual maturation in females and males respectively, and then decreased markedly after spawning. These findings indicated that the fluctuations in the levels of both steroids were closely related to the reproductive cycle, thus E2 and T could have a role as endogenous modulators in sex determination, development and maturation of C. angulata. In addition, a full-length cDNA (3161bp) encoding a peptide of 744 amino acids of estrogen receptor (ER) from C. angulata was obtained and the similarities of its deduced amino acid sequence to these of other molluscan species were more than 60%. caER mRNA transcript was most abundantly expressed in ovary (P<0.05) and in situ hybridization revealed that the distribution of this gene was expressed exclusively in “auxiliary cells” of ovary. Similar to the variation trends of E2, the expression of caER in the ovary continuously increased from initiation to ripeness stages (P<0.05), and then decreased sharply to the lowest level in the partially spent stage (P<0.05), whereas the caER mRNA transcript of male oyster in the testis maintained a relatively stable low level during the reproductive cycle. These findings suggested that ER may play an important role in the gonad development of oysters.

How the evolutionary theory of aging can guide us in the search for aging genes

It is a stroke of irony that lifespan — the principal phenotype used to search for aging genes — is a terrible phenotype for genetic analysis. Lifespan has relatively low heritability under most conditions, and it is affected by chronic, age-related diseases that confound its use as a biomarker of aging. If the majority of aging genes are pleiotropic, as proposed by the evolutionary theory of aging, an opportunity is provided to identify these genes through the “back door,” using phenotypes that are more amenable to genetic analysis. To choose the pleiotropic phenotype for our studies, we went back more than 50 years to Williams [1], who, in his seminal paper, specified four “physiological expectations that follow from the theory,” two of which we applied: “Rapid individual development should be correlated with rapid senescence,” and, to specify a particular developmental phenotype, “The time of reproductive maturation should mark the onset of senescence.” Therefore, to search for genes that regulate lifespan, we looked in the other direction — for genes that govern reproductive maturation. We started our search for pleiotropic aging genes by evaluating the age of female sexual maturity in the highly diverse, 32-inbred strain panel provided by The Jackson Laboratory Nathan Shock Center. As predicted by the evolutionary theory of aging, age of vaginal patency (VP) correlated positively with lifespan across strains. Interestingly, it also correlated negatively with circulating IGF1. And, because, in the same 32 strains of mice, 6-month IGF1 levels also correlate negatively with lifespan [2], it is likely that IGF1 mediates a significant portion of the linkage of reproductive maturation with aging and lifespan. We tested this idea in a congenic C57BL/6J (B6) mouse that carries a portion of Chr 10 from the C3H/HeJ strain. In congenic females, circulating IGF1 was elevated and as predicted, age of VP was accelerated and lifespan was shortened. (In males, IGF1 was not elevated and lifespan was not shortened.) Thus, the stage was set to begin a search for pleiotropic genes that influence both female reproductive maturation and lifespan in the strain panel. Using haplotype association mapping, we identified three loci (Vpq1 [Chr 4], Vpq2 and Vpq3 [both on Chr 16]) that accounted for 76% of the variance in age of VP across strains. Again, IGF1 may be involved. Age of VP was delayed and circulating IGF1 was diminished in the B6.PWD–Chr 16 consomic strain, in which the PWD/PhJ Chr 16, carrying the late age of VP haplotype at Vpq3, replaces the B6 Chr 16, carrying an intermediate age of VP haplotype. Haplotypes of Vpq 3 also associated with differences in lifespan, strongly supporting the hypothesis that a gene at Vpq3 mediates an antagonistic relationship between age of VP and lifespan. We then used an arsenal of bioinformatic and genetic strategies to query Vpq3 for candidate genes, which ultimately designated nuclear receptor interacting protein 1 (Nrip1) as a strong candidate. NRIP1 is a regulator of nuclear receptors that have broad functions in regulating cell growth, cell death, and metabolism. Nrip1, as a transcriptional repressor of PGC-1α and β, could promote senescence by suppressing mitochondrial biogenesis [3]. Nrip1 null (−/−) mice are smaller and leaner, are resistant to high-fat diet-induced obesity, and show increased glucose tolerance and insulin sensitivity [4,5] — mimicking characteristics found in calorierestricted mice. We compared Nrip1 null mice with their normal littermates. Results verified the hypothesis — generated by genetic and bioinformatic analyses — that knocking out Nrip1 could significantly decrease IGF1 level and delay age of VP. Lifespan studies of Nrip1 null mice are in process. Additional work is necessary to verify Nrip1 as an aging gene that mediates an antagonistic relationship between female reproductive maturation and lifespan. But our present analysis does provide direct support for the hypothesis that genes that regulate IGF1 constitute an entire category of pleiotropic genes that influence both reproductive maturation and aging. Our results also suggest that genes such as Nrip1 — with highly pleiotropic effects on metabolism and cell turnover as well as on cell signaling and life history traits — are the types of genes that have the greatest impact on aging. Our work demonstrates that the utilization of pleiotropy in strategies informed by evolutionary theory is an effective approach in the search for genes that regulate aging.

Vaginal microbicides to prevent human immunodeficiency virus infection in women: Perspectives on the female genital tract, sexual maturity and mucosal inflammation

Topically applied vaginal microbicides to protect against human immunodeficiency (HIV) virus infection offer an important female-controlled prevention strategy. Microbicides have been in development for more than 2 decades, and have included various agents that disrupt cellular and microbial membranes (surfactants), restore the natural acidic protective pH of the vagina (acid buffers), and those that interfere with interactions between HIV envelope proteins and cellular receptors (anionic polymers). Although none of these candidate microbicides have shown significant protection against HIV in clinical trials, a topical gel, including the antiretroviral drug tenofovir (TFV) 1% was the first microbicide to be tested to show some protection against HIV infection. This review explores the effect of female genital tract biology and anatomy, mucosal inflammation, and age on the effectiveness of microbicides to prevent HIV infection.

Male preference and female cues: males assess female sexual maturity and mating status in a web-building spider

Reproductive success relies on communication signals used by females to exert mate attraction and assessment of female reproductive value by males. During mate search males of the spider, Stegodyphus lineatus experience high mortality and low female encounter rate. Females vary in sexual maturity and mating status (virgin and mated) and hence in reproductive value for males, which should influence male mating effort. Due to high costs of remating, only virgin females are expected to signal mate attraction. Males would benefit from mating preferentially with virgins due to the costs of overcoming mated females' resistance, although they gain paternity share. Males should avoid immature females, unless guarding precopulatory to access females on maturation. Low encounter rates predict males to invest also in females of inferior reproductive value. We investigated male ability to discriminate immature, virgin, and mated females by assessing: the number of females males visit in the field; male mating effort and male discrimination of females based on silk cues in laboratory trials. In the field, males were found most frequently with virgin females. Male mating effort, copulation success, and preference based on silk cues were higher with mature compared with immature females. Our data suggest that females signal sexual receptivity and that males are able to discriminate both sexual maturity and mating status, however, males do not exert strong preference for virgins. The combination of high costs of mate search and low encounter rate likely exerts selection on males to mate indiscriminately and overcome female resistance to remating.

Reproductive biology of the tub gurnard Trigla lucerna (linnaeus, 1758), in the Libyan eastern coast of Mediterranean Sea.

The reproductive biology of Trigla lucerna, (family: Triglidae) inhabiting Libyan eastern coast was studied during the period from January to December 2007. There were monthly variation in sex ratio, and a tendency for more females (731 fish, 52.2%) than males (669 fish, 47.8%) for the collected population. Overall sex ratio was 1: 1.09 for males to females. The male of Trigla lucerna attained its first maturity at the total length of 13.9 cm, while the first sexual maturity of female was attained at 15.3 cm. The gonado-somatic indices of males were lower than that of females. Males and females have a definite breeding season which extends from January till March. An increase in oocyte diameter was evident in November (with an average of 225 µ) and this increase continued in the following months till March, with an average value of 498µ. The absolute fecunncldity ranged from 678 to 10047 eggs for fish length ranging from 13.5 to 22.6 cm. Also, the fecundity increased from 755 to 10055 eggs with the increase of weight from 16.7 to 108.2 g.

Temporal Dynamics of Reproduction of the Neotropical Fish,Crenicichla menezesi(Perciformes: Cichlidae)

The reproductive biology and the gonadal development cycle of the Neotropical cichlid fish, Crenicichla menezesi, is described. This species exhibits sexual dimorphism only during the spawning season. First sexual maturity of females is attained earlier than the males. Both macroscopic and histological investigations of ovaries and testes revealed four stages of gonadal maturation. Mean batch fecundity of females was 372 (±10,41) of mature oocytes. This species is a partial spawner, with an extended spawning period. Monthly values of GSI and the condition factor are negatively correlated during the gonadal development cycle of this species.

Reproduction and population dynamics of Cheirodon interruptus (Ostariophysi: Characidae) in El Portugués, a stream in the upper watershed of the Samborombón River, Argentina

The reproductive period of Cheirodon interruptus was determined by analyzing 1658 individuals collected monthly in the stream El Portugués, Argentina, from May 2004 to April 2005. Two prolonged spawning seasons, one in spring and another in autumn, were observed based on the maturity stages and gonadosomatic index (GSI) of female specimens. The mean monthly GSI of males was significantly correlated with depth. In females, the GSI exhibited a significant correlation with photoperiod and depth. The remaining environmental variables, including temperature, pH, conductivity, and monthly rainfall, did not show a correlation with the mean monthly GSI. The first sexual maturity in females and males was reached within the 24-26 mm standard length class. The mean absolute fecundity was 448 oocytes (SD = 217.8), and the mean relative fecundity was 0.33 (SD = 0.097) oocytes per milligram of body weight; this species is a multiple spawner. The oocyte diameter ranged from 0.05 to 0.70 mm, with a mean of 0.48 mm (SD = 0.16).

Why become speckled? Ontogeny and function of speckling in Shark Bay bottlenose dolphins (Tursiops sp.)1

AbstractTo date, color patterns have been used to assess cetacean age and taxonomic status, but few studies have determined precise correlates of coloration with known age or investigated its function. Here, we examine the ontogeny of speckling in 88 bottlenose dolphins (Tursiops sp.) in Shark Bay, Australia, of known age, tracked from birth to age 34. Ventral speckles first appear in the genital area at a mean age of 10.2 ± 0.35 yr (range = 7.6–12.7 yr). Throughout their life span, speckles increase in number and density, particularly along the ventral and lateral sides. The timing of speckle onset does not significantly differ by sex but is related to sexual maturity in females. The age of speckle onset in the genital area correlates with the age of first known parturition. In terms of speckle function, we discuss two hypotheses commonly proffered to explain color variation, concealment, and communication. Concealment from predators or prey is unlikely to explain speckle development in Shark Bay Tursiops because the onset occurs long after peak predation risk and initial hunting success (at 3 mo of age). We suggest that speckle patterns offer reliable cues on reproductive status and/or condition and could, thus, serve a communicative or some other function.

Reproductive delay in the female Cape ground squirrel (Xerus inauris)

Abstract We studied the simultaneous effects of social and environmental factors on the age of sexual maturity to identify the major determinants of reproductive delay in the cooperatively breeding female Cape ground squirrel (Xerus inauris). We verified inhibition of sexual maturity by monitoring reproductive behaviors and hormones (using a noninvasive fecal steroid hormone analysis) in prereproductive and reproductive females from 2 populations of squirrels found in southern Africa. We found that 2 social parameters hold the most influence on the timing of female sexual maturity; specifically, the number of adult breeding female group mates and related adult male group mates were associated with a substantial inhibition of female reproductive maturity. Subadult females in social groups with 0 or 1 adult breeding female became sexually mature significantly earlier than similar-aged females in social groups with ≥2 adult breeding females. Likewise, subadult females in social groups with <2 related adult m...

Reproducción en cautiverio de Crocodylus moreletii en Tabasco, México

Between 1990 and 1993 we studied the Morelet's crocodile reproduction in captivity, with a sample of 27 males and 109 females. Females were larger (60 to 140 cm SVL) than previously known. Most frequent size of nesting females was between 81 and 100 cm of SVL. Sexual maturity in females was attained at a minimum size of 135 cm. The courtship, mating, nesting and hatching occurred between February and September. In the sample of females 8.25% nesting in each one of the 4 years of study, 11% in 3 years, 28.44% in 2, and 52.29% in one. The reproductive events mentioned were related to the highest average environmental temperatures, and nesting to the beginning of the rainy season. The number of eggs per nest fluctuated between 6 and 50 (29.24 ± 8.72). The body size and body mass were not good fine predictors of the reproductive characteristics. There was not correlation between egg characteristics and the clutch size, being different from the expected pattern. The body size and body mass were only slight correlated to clutch size, therefore, environmental factors, the reproductive quality of males, the physical condition of the females, the stocking rates, sex ratios, and territoriality may be influencing the reproductive traits.

Production of Transgenic Mice by Type-A Spermatogonia-Mediated Gene Transfer

Abstract Type-A spermatogonia first appear at between 3-7 d postnatally in mice and are the only immortalized diploid cells that reproduce in adulthood in these animals. In our current study, we explored the feasibility of producing stable transgenic mice using these cells. Enhanced pEGFP-N1 plasmids were suspended in ExGen500 transfection reagent and injected at different angles into the testes of 7-d-old male ICR mice. The resulting type-A spermatogonia-mediated gene transfer (TASMGT) mice were then mated with normal females at different stages of sexual maturity (6, 12, and 24 wk). The integration and expression of the introduced EGFP gene was evaluated in the F 1 transgenic offspring by PCR and Southern blotting analysis. The foreign gene integration rates for a low-dose group (15 μL gene suspension injected into each testis) and a high-dose group (30 μL suspensions injected) at the three stages of female sexual maturity tested were 11.76% (2/17), 14.29% (3/21), and 11.11% (2/18), and 5% (1/20), 5.56% (1/18), and 0 (0/17), respectively. The average integration rates for these two dose groups were 12.5% (7/56) and 3.64% (2/55), respectively, which was a significant difference ( P<0.05). Semi-quantitative RT-PCR analysis further showed that the introduced GFP gene was expressed in 3/9 integration mice. In addition, GFP expression was observed in the sperm cells from the TASMGT mice, and also in the embryos and F 2 pups from the F 1 generation transgenic mice. Hence, although the foreign gene integration rate for TASMGT is not high and the transgenic offspring show as yet unexplained defects, our results indicate that this method is a potentially feasible and reproducible new approach to creating transgenic mice.

Seasonal changes of oestradiol-17β and testosterone concentrations in the gonad of the razor clam Sinonovacula constricta (Lamarck, 1818)

Seasonal variations in oestradiol-17b and testosterone levels of the razor clam Sinonovacula constricta from the Yellow River delta in China were investigated in relation to the reproductive cycle from April 2007 to March 2008. Histological analysis indicated that gametogenesis began in June –July when water temperature was 22.0 –27.08C and ended during September–October when food was abundant. Oestradiol-17b and testosterone concentrations were determined by enzyme-linked immunosorbent assay in the gonad of S. constricta. Oestradiol-17b concentration in the female gonads was higher than that in the male gonads, while testosterone concentration in the male gonads was higher than that in the female gonads during sexual maturation. A positive correlation between oestradiol-17b and mean oocyte diameter was observed during the study period (r ¼ 0.664, P , 0.05), indicating that oestradiol-17b may play an important role in regulating vitellogenesis. Oestradiol-17b and testosterone increased during sexual maturation in females and males, respectively, and then decreased markedly after spawning. These findings indicated that the fluctuations in the levels of both steroids were closely related to the reproductive cycle, thus oestradiol-17b and testosterone could have a role as endogenous modulators in sex determination, development and maturation of S. constricta.

Reproducción y dinámica poblacional de Cheirodon interruptus (Ostariophysi: Characidae) en el arroyo El Portugués, alta cuenca del río Samborombón, Argentina

The reproductive period of Cheirodon interruptus was determined by analyzing 1658 individuals collected monthly in the stream El Portugues, Argentina, from May 2004 to April 2005. Two prolonged spawning seasons, one in spring and another in autumn, were observed based on the maturity stages and gonadosomatic index (GSI) of female specimens. The mean monthly GSI of males was significantly correlated with depth. In females, the GSI exhibited a significant correlation with photoperiod and depth. The remaining environmental variables, including temperature, pH, conductivity, and monthly rainfall, did not show a correlation with the mean monthly GSI. The first sexual maturity in females and males was reached within the 24-26 mm standard length class. The mean absolute fecundity was 448 oocytes (SD = 217.8), and the mean relative fecundity was 0.33 (SD = 0.097) oocytes per milligram of body weight; this species is a multiple spawner. The oocyte diameter ranged from 0.05 to 0.70 mm, with a mean of 0.48 mm (SD = 0.16).

Paired-laser photogrammetry as a simple and accurate system for measuring the body size of free-ranging manta rays Manta alfredi

Morphometrics are useful for describing and managing animal populations, but mea- surements can be difficult to obtain, especially on large free-ranging aquatic animals. The accuracy and precision of paired-laser photogrammetry were tested as a simple and non-invasive remote sens- ing system for measuring the body size of free-ranging, resident manta rays Manta alfredi, a newly described species that is poorly understood. Based on repeated measurements of a pipe of known size, the paired-laser system proved accurate (mean error of 0.39%) and precise (CV = 0.54%). Repeated measurements on 154 different manta rays visiting a cleaning station off Maui, Hawaii, produced a mean CV of 1.46%. Disc length (DL) measurements were more precise than disc width (DW) measurements, and an empirically derived disc ratio (DR) function was applied to convert DL to DW measurements for standard comparison with other studies. Sexual dimorphism was present with the largest female (3.64 m DW) 18% larger than the largest male (3.03 m DW). Sexual maturity in females, based on evidence of pregnancy and mating scars, was conservatively determined to be 3.37 m DW. The DW at which 50% of the males were likely to be mature (based on clasper length) was between 2.7 and 2.8 m. The absence of individuals < 2.5 m DW suggests that age class segrega- tion occurs in this population. Paired-laser photogrammetry proved to be a simple, non-invasive, accurate, and precise method for sizing free-ranging manta rays. Repeated measurements on known individuals over time could provide population growth parameters needed for adequate manage- ment of this poorly understood species.

Gonadosomatic index-based size at first sexual maturity and fecundity indices of the Indian River shad Gudusia chapra (Clupeidae) in the Ganges River (NW Bangladesh)

Summary The present study aims to estimate the size at first sexual maturity and fecundity for female Gudusia chapra from the lower Ganges River, northwestern Bangladesh. A total of 250 female specimens, 3.60–13.70 cm in standard length (SL) and 1.00–43.60 g in body weight (BW), were collected during March–August 2006. The gonadosomatic index (GSI) for females was calculated by the equation, GSI (%) = (GW/BW) × 100. The size at first sexual maturity of females was estimated by the relationship between their gonadosomatic index and standard length. The specimen larger (≥8.00 cm in SL) than first size at sexual maturity was used for the estimation of fecundity. The size at first sexual maturity for female G. chapra was considered to be 8.00 cm SL in the Ganges River. The mean total fecundity was 20200 ± 6500 and ranged from 10800 to 36200. This study should be useful for fisheries biologists/managers to impose adequate regulations for sustainable-fishery management in the Ganges River and elsewhere in Bangladesh.

Feeding habits, sexual dimorphism and size at maturity of the lizard Cnemidophorus ocellifer (Spix, 1825) (Teiidae) in a reforested restinga habitat in northeastern Brazil

The feeding habits, the sexual dimorphism in size and sexual maturity of the actively foraging lizard Cnemidophorusocellifer were analysed in an area of a reforested Restinga habitat located in the municipality of Mataraca, along the northern-most coast of Paraíba State, Brazil. Seventy-five specimens of C. ocellifer were examined (46 males and 29A females). Of this total, only 23 specimens had prey in their stomachs. The most frequent prey consumed items were orthopterans (50%), coleopterans (23.9%) and arachnids (10.9%); termites and insect larvae were less consumed (both with 2.2%). There were no significant differences observed between the numbers of prey consumed by either males or females. There were significant differences in SVL (snout-vent length) between the sexes, with males attaining larger SVL values. When the influence of SVL was removed from the analyses, sexual dimorphism in the form was still reflected in the head size of these lizards. Sexual maturity in females and males was attained with SVL of 42.2 and 49.0 mm respectively. Although no significant difference was observed between the SVL of the females and the number of eggs produced, there was a clear tendency for larger females to produce more eggs. The low structural complexity of the vegetation and the poor soil quality in the reforested restinga area examined does not furnish favourable habitat for insect and termite larvae, contributing to the marked differences in the diet of the population of C. ocellifer observed in the present study in relation to the diet of their conspecifics in undisturbed areas of restinga, cerrado and caatinga.