Decrease In Gonadosomatic Index Research Articles

Contraceptive-Pill-Sourced Synthetic Estrogen and Progestogen in Water Causes Decrease in GSI and HSI and Alters Blood Glucose Levels in Climbing Perch (Anabas testudineus)

The present study was conducted to understand the changes in gonads and hematological parameters in climbing perch (Anabas testudineus) exposed to synthetic estrogen and progestogen [mixture of ethinylestradiol (EE2) and desogestrel (DES)]. Climbing perch were exposed to four different concentrations of EE2/DES mixtures, viz. 0 ng of EE2 and DES/L (T0), 3 ng EE2 and 15 ng DES/L (T3), 30 ng EE2 and 150 ng DES/L (T30), and 300 ng EE2 and 1500 ng DES/L (T300) for 60 days. On days 45 and 60, samples were taken to assess changes in somatic indexes, gonad histology, and hematological parameters. The gonadosomatic index (GSI) increased in both females and males with increasing concentrations of estrogen mixtures except for T30 females, which was the lowest among all\four treatments. The hepatosomatic index (HSI) was observed to be increased in males as estrogen content increased. However, compared to fish at T0, HSI in female individuals did not vary in T30 fish, where the value was the highest among all the treatments. On day 45, histological observations showed no feminization or intersexuality but several germ-cell deformities in the ovary (adhesion, degenerated oocyte wall, degenerated granulose layer, increased interfollicular space, atretic follicle, and cytoplasmic clumping) and testes (increased interstitial area, focal loss of spermatocyte, dilation of the lumen, breakage of tubular epithelium, and elongated seminiferous tubule) were observed in fish exposed to EE2 and DES. Fish reared at T30 had lower RBC count, hemoglobin (Hb), glucose, and hematocrit levels. On day 60, fish reared at T30 had the highest Hb content compared to fish raised in other treatment conditions. WBC was progressively higher with increasing EE2/DES concentrations. Significant erythrocyte cytoplasmic abnormalities and erythrocyte nuclear abnormalities were observed in fish exposed to higher EE2/DES concentrations. The present study provides insights into the adverse impacts of synthetic estrogens sourced from human contraceptive pills on fish physiology.

Structural damage in liver, gonads, and reduction in spawning performance and alteration in the haematological parameter of Anabas testudineus by glyphosate‐ a herbicide

The increasing demand for herbicides in agricultural fields affected aquatic environments as they entered into water bodies by agricultural runoff. Glyphosate (GLY), an organophosphate herbicide, is widely used in India for weed control. This study aimed to evaluate the toxic effects of GLY on climbing perch Anabas testudineus by studying its effects on the gonadosomatic index (GSI), hepatosomatic index (HSI), gonad and liver histology, spawning performance, and haematological parameters (RBC, WBC, haemoglobin). In this study, Anabas testudineus were exposed to three sub-lethal concentrations of GLY such as T1: 2.6 ppm (1/30th of 48h LC50), T2: 3.9 ppm (1/20th of 48h LC50) and T3: 7.8 ppm (1/10th of 48 hr LC50) for 45 days with 12 fish in each tank. Results indicated a significant decrease in GSI, HSI, structural alterations in testis, and ovary on 30th and 45th days of exposure. Vacuolation in tissue, dilution of sinusoid, altered tissue architecture in the liver, reduction in spawning performances (fertilization and hatching rate), increase in WBC count, decrease in RBC number and haemoglobin content were observed in all treatment groups on the 45th day exposure. Thus, the outcome of the present study revealed that the herbicide could deleteriously impair reproductive fitness, alter the liver structure, and haematological parameter of A. testudineus with a possible reduction in growth and population size.

Effect of exposure to palm oil mill effluent on reproductive impairment of male Nile Tilapia (Oreochromis niloticus, Linnaeus 1758)

One of the negative impacts arising from the existence of palm oil mill industries is the increase of pollution from Palm Oil Mill Effluent (POME), particularly for the aquatic environment. This study was conducted to investigate the reproductive impairment of male Nile tilapia (Oreochromis niloticus Linnaeus 1758) after exposed to POME. An experiment of a chronic test was carried out using a completely randomized design consisting four treatments with five replication: control (0 mg/L POME), treatment A (1.565 mg/L POME), treatment B (2.347 mg/L POME), and treatment C (3.130 mg/L POME). The exposure of POME was performed for 45 days. Reproductive hormone concentration, gonadosomatic index and spermatocrite value in each treatment statistically analyzed by using one-way analysis of variance (ANOVA). Results showed that the POME exposure had no significant impact on estradiol and testosterone concentrations (p>0.05), but, it triggered a decline in the progesterone concentration (p<0.05). Progesterone concentration decreased significantly from 0.57 ± 0.24 ng/mL in control to 0.28 ± 0.04 ng/mL in treatment C. The hormonal decline resulted in a significant decrease in gonadosomatic index and spermatocrite of male Nile Tilapi (p<0.05). In conclusion, exposure to POME induced reproductive impairment in male Nile Tilapia.

Knockout of MCT1 results in total absence of spermatozoa, sex hormones dysregulation, and morphological alterations in the testicular tissue.

Lactate is a key metabolite for the normal occurrence of spermatogenesis. In the testis, lactate is produced by the Sertoli cells and transported to germline cells. Monocarboxylate transporters (MCTs) are key players in that process. Among the family of MCTs, MCT1 is at least partly responsible for lactate uptake by the germ cells. We aimed to perform a first assessment of the role of MCT1 in male reproductive potential. Mct1 conditional knockout (cKO) mice were used for morphometric evaluation, testicular morphology, and sperm parameter assessment. Serum steroid hormones levels were also measured. cKO animals showed a decrease in gonadosomatic index, testis weight, and seminiferous tubular diameters. Deletion of MCT1 also causes morphological changes in the organization of the seminiferous tubules and on Sertoli cell morphology. These changes resulted in failure of spermatogenesis with depletion of germ cells and total absence of spermatozoa. MCT1 cKO animals presented also hormonal dysregulation, with a decrease in serum 17β-estradiol levels. In conclusion, MCT1 is pivotal for male reproductive potential. Absence of MCT1 results in maintenance of undifferentiated spermatogonia pool and compromised sperm production.

Recovery of gonadal development in tiger puffer Takifugu rubripes after exposure to 17β-estradiol during early life stages

The aim of the present study was to investigate the long-term effects of 17β-estradiol (E2) exposure on gonadal development in the tiger puff er (Takifugu rubripes), which has a genetic sex determination system of male homogametic XY-XX. Tiger puff er larvae were exposed to 1, 10 and 100 μg/L E2 from 15 to 100 days post-hatch (dph) and then maintained in clean seawater until 400 dph. Changes in sex ratio, gonadal structure and gonadosomatic index (GSI) were monitored at 100, 160, 270 and 400 dph. Sex-associated single nucleotide polymorphism (SNP) markers were used to analyze the genetic sex of samples, except those at 100 dph. Exposure had a positive effect on the conversion of genetically male gonads into phenotypically female gonads at 100 dph. However, gonads from 60% of genetic XY males in the 1-μg/L E2 group and 100% in the 10-μg/L E2 group developed intersexual gonads at 160 dph; gonads of all genetic XY males in the two treatment groups reverted to testis by 270 dph. While 38%, 57% and 44% of gonads of XY fish in the 100-μg/L E2 group reverted to intersexual gonads at 160, 270 and 400 dph, respectively, none reverted to testis after E2 treatment. In addition, E2 exposure inhibited gonadal growth of both genetic sexes, as indicated by the clear dose-dependent decrease in GSI at 270 and 400 dph. The results showed that exposure to E2 during the early life stages of tiger puff er disrupted gonadal development, but that fish recovered after migration to clean seawater. The study suggests the potential use of tiger puff er as a valuable indicator species to evaluate the effects of environmental estrogens on marine fish, thereby protecting valuable fishery resources.

Histopathological Effects on Testis of Adult Male Carp, <i>Cyprinus carpio carpio</i>, Following Exposure to Graded Concentrations of Water-Borne Bisphenol A

Purpose: To evaluate the estrogenic effect of Bisphenol A (BPA), an endocrine disruptor on the histological features in carp testis Methods: Adult male fish, koi carp, Cyprinus carpio carpio, were exposed to three graded concentrations of BPA (10, 100 and 1000 µg/L) for a period of 21 days. A single dose of 17-β estradiol (1 ng/L) was used as positive control. The end points assessed at the end of the exposure period were condition factor, hepatosomatic index (HSI), gonadosomatic index (GSI), histopathological changes in the testis and lobular diameter. Results: BPA caused a significant decrease in gonadosomatic index (GSI) of the fish at the median concentration of 100 µg/L. The major alterations observed in the gonad structure were a significant decrease (p ≤ 0.001) in the lobular diameter (65.1 ± 12.2 µm) compared with control (211.7 ± 36.60 µm) and complete loss in lobular structure with degenerating spermatozoa in some carps. The histopathological effects also include delayed sperm maturation and impaired spermatogenesis. Conclusion: The findings clearly show marked adverse histopathological effects of gonads of adult carps when exposed to BPA.

Kolaviron protects against benzo[a]pyrene-induced functional alterations along the brain-pituitary-gonadal axis in male rats

Exposure to benzo[a]pyrene (B[a]P) is well reported to be associated with neurological and reproductive dysfunctions. The present study investigated the influence of kolaviron, an isolated biflavonoid from the seed of Garcinia kola, on functional alterations along the brain-pituitary-gonadal axis in male rats exposed to B[a]P. Benzo[a]pyrene was orally administered at a dose of 10mg/kg alone or orally co-administered with kolaviron at 100 and 200mg/kg for 15 consecutive days. Administration of B[a]P significantly (p<0.05) decreased plasma levels of pituitary hormones namely follicle-stimulating hormone (FSH) and prolactin but increased luteinizing hormone (LH) by 47%, 55% and 20.9%, respectively, when compared with the control. The significant decrease in gonadosomatic index (GSI) was accompanied by significant decrease in testosterone production and sperm functional parameters in the B[a]P-treated rats. Moreover, B[a]P-treated rats showed significant elevation in the circulatory concentrations of pro-inflammatory cytokines and oxidative stress indices in the brain, testes and sperm of B[a]P-treated rats. Light microscopy revealed severe necrosis of the Purkinje cells in the cerebellum, neuronal degeneration of the cerebral cortex, neuronal necrosis of the hippocampus and testicular atrophy in B[a]P-treated rats. Kolaviron co-treatment significantly ameliorated B[a]P mediated damages by suppressing pro-inflammatory mediators and enhancing the antioxidant status, neuroendocrine function, sperm characteristics and improving the architecture of the brain and testes in B[a]P-treated rats. The findings in the present investigation highlight that kolaviron may be developed to novel therapeutic agent against toxicity resulting from B[a]P exposure.

Molecular signatures in rainbow darter (Etheostoma caeruleum) inhabiting an urbanized river reach receiving wastewater effluents

Rainbow darter (Etheostoma caeruleum) is a small benthic fish species found in North America that are abundant and distributed throughout the Grand River watershed, ON, Canada. Rainbow darter exhibit intersex in males at sites adjacent to municipal wastewater effluents (MWWE). In October 2010, female and male rainbow darter were collected at 3 sites (1 upstream reference and 2 downstream exposed sites) in the Grand River near the cities of Kitchener and Waterloo. The primary objectives of this research were (1) to characterize the responses of whole organism endpoints (i.e. condition factor (K), liversomatic (LSI) and gonadosomatic index (GSI), histopathology) to MWWEs and (2) to identify transcripts showing altered steady state abundance with exposure to MWWE in fish inhabiting municipal wastewater effluent-exposed areas. Genes measured in this study included vitellogenin, Sry-box containing protein 9 (sox9), forkhead box L2 (foxl2), doublesex and mab-3 related transcription factor 1 (dmrt1), cytochrome P450, family 11, subfamily A, polypeptide 1 (cyp11a) as well as estrogen (esr1, esrb) and androgen (ar) receptors. There were no changes in condition factor; however, there was a significant increase in LSI and a decrease in GSI in fish inhabiting downstream environments when compared with fish collected from the reference site. Males had a high incidence (∼70%) of intersex in downstream sites; characterized by the presence of oocytes within the testis. In the gonad, there were sex specific differences for genes related to sexual differentiation; dmrt1 was only expressed in males whereas foxl2 and sox9 were highly expressed in females compared to males. Expression levels of ar and esr1 were higher in females than males. Conversely, esrb was not differentially expressed between sexes or among sites. There were no differences detected for the genes investigated within sex among sites. This study is the first to report on gene expression changes in the rainbow darter, with emphasis on the differences in transcript abundance between sexes and how these changes relate to exposures to MWWEs. Molecular approaches are being investigated for their potential application to field ecotoxicology, and molecular bioassays for relevant, sentinel species in environmental monitoring programs are required to better understand the impact of anthropogenic impacts on species at risk in river systems.

Reproductive Mode of Fejervarya limnocharis (Anura: Ranidae) Caught from Mae Sot, Thailand Based on Its Gonadosomatic Indices.

Amphibians show a variety of reproductive modes and strategies. The cyclicity and continuity of reproduction can often be predicted from the annual gonadosomatic index trends in a species specific manner. This research aims to document the female and male gonadosomatic index profiles and to ascertain the reproductive cyclicity or continuity of Fejervarya limnocharis (Anura: Ranidae) caught in Mae Sot, Tak Province, Thailand. Frogs were collected monthly between November 2007 and October 2009 in rice fields and their surrounding areas in the study site. For each frog, total weight and ovarian/testicular weight were measured to obtain the female and male gonadosomatic index. The number of female individuals with mature eggs (postvitellogenic eggs) was also counted. The results showed that female frogs had two main surges of increased GSI in March and September of 2008. Alternatively, male frogs showed a more gradual increase and decrease in gonadosomatic index, thus the index remaining high throughout the year. This study concluded that while F. limnocharis in this area is essentially a continuous breeder, it is more optimized for a cyclic reproduction mode with two breeding cycles during the rainy season.

Effect of cadmium on the ovarian development in the freshwater prawn Macrobrachium rosenbergii (De Man)

In this investigation, effect of cadmium chloride (25 μg/l) on oogenesis of freshwater prawn, Macrobrachium rosenbergii was studied. In vivo experiments were performed with both intact and eyestalk ablated prawns. The intact, cadmium-exposed prawns exhibited decrease in Gonado Somatic Index (GSI) and ovarian development compared to controls. Whereas, ablated treated ovary showed reduction of yolk material and oocyte membrane thickness at the end of 15 days exposure. Interestingly, the control prawn showed normal cellular architecture of gills, hepatopancreas and ovary with mature oocytes. But, the gills of treated prawns showed lamellar hypertrophy, cuticular dystrophy and irregular arrangement of epithelial cells. Hepatopancreas showed reduction in both tubular diameter and basement membrane thickness. Conspicuously, ovary showed hypertrophied primary oocytes with more vacuoles in intact-treated group. Cadmium had increased gonad inhibiting hormone (GIH) secretion and decreased gonad stimulating hormone (GSH) release as evident with the retardation of gonadal maturation in the intact prawns.

Influence of environmental variables and reproduction on the gonadal fatty acid profile of tropical scallop Nodipecten nodosus

We examined the influence of the reproductive cycle and environmental variables on the gonadal fatty acid profile in the tropical scallop Nodipecten nodosus. Individuals from a natural population in north-eastern Venezuela (Caribbean Sea) were sampled monthly during one year. The gonadosomatic index (GSI) and a visual assessment of gonadic status are also reported. The environmental conditions characterized by chlorophyll a, temperature and seston concentration were measured in parallel. The highest reproductive activity, with a GSI of 13-18%, was observed from November 2003 to April 2004, and a decrease in GSI, taken as an indication of three spawning periods, was recorded in October, January and May-June. The GSI was 5-8% outside these intervals. A similar trend was observed in maturity stage frequency. Statistical analysis (MDS-ANOSIM) established two different periods; one dominated by upwelling (January to July) and the other characteristic of non-upwelling conditions (August to December). The fatty acids 16:0, 22:6n-3, 20:5n-3 and 16:1n-7 were responsible for the differences between two periods and explained 50% of the observed variance. Accordingly, during the upwelling period, fatty acids such as 22:6n-3 were positively correlated with temperature, organic seston and bivalves in the spent sexual stage and inversely related to the GSI. Furthermore, individuals in the ripe sexual stage were positively related to 20:5n-3 and 18:3n-3, whereas chlorophyll a was directly related to 18:1n-7 and 16:1n-7. In the non-upwelling period, a significant and positive correlation was obtained between fatty acids such as 20:5n-3 and 22:6n-3 and the GSI and the bivalves in the ripe sexual stage, whereas these acids were inversely correlated with the spent sexual stage. In addition, chlorophyll a was positively related to 18:1n-9 and 18:2n-6. Changes in the gonadal fatty acid profile of N. nodosus were influenced by the environmental variables (exogenous factors) during the upwelling and non-upwelling periods and by reproductions (endogenous factors).

Reduction in the estrogenic activity of a treated sewage effluent discharge to an english river as a result of a decrease in the concentration of industrially derived surfactants

As a result of the introduction of tighter discharge limits and effluent treatment processes at source, the concentration of alkylphenol ethoxylates and nonylphenol present in the final effluent discharge from a sewage treatment works that treats trade effluent from the textiles industry was reduced. The estrogenic effects of the final effluent discharge to the Aire River were compared over a four-year period during which various treatment measures were introduced. Male rainbow trout exposed to the effluent on four occasions in consecutive years (1994-1997) showed a reduction in the level of induced vitellogenesis between 1994 and 1997. A marked decrease in gonadosomatic index (GSI) and increase in heptaosomatic index (HSI) was measured in fish exposed to the effluent in 1994. In successive years, these differences diminished, and in the case of the GSI no measurable difference was observed between fish exposed to the final effluent or those in the control group in 1997. However, an increase in HSI was still measurable in 1997 in fish exposed to the final effluent and at sites farther downstream. The reduction in the effects of the effluent paralleled the reduction in the concentration of nonylphenol as well as its mono- and diethoxylates, which have been demonstrated to produce estrogenic effects in trout exposed to these compounds in the laboratory. This study demonstrates that the setting of more restricted discharge limits for known estrogenic chemicals of industrial origin can lead to significant reductions in the estrogenic activity of the watercourses into which the effluents are discharged.

REDUCTION IN THE ESTROGENIC ACTIVITY OF A TREATED SEWAGE EFFLUENT DISCHARGE TO AN ENGLISH RIVER AS A RESULT OF A DECREASE IN THE CONCENTRATION OF INDUSTRIALLY DERIVED SURFACTANTS

As a result of the introduction of tighter discharge limits and effluent treatment processes at source, the concentration of alkylphenol ethoxylates and nonylphenol present in the final effluent discharge from a sewage treatment works that treats trade effluent from the textiles industry was reduced. The estrogenic effects of the final effluent discharge to the Aire River were compared over a four-year period during which various treatment measures were introduced. Male rainbow trout exposed to the effluent on four occasions in consecutive years (1994–1997) showed a reduction in the level of induced vitellogenesis between 1994 and 1997. A marked decrease in gonadosomatic index (GSI) and increase in heptaosomatic index (HSI) was measured in fish exposed to the effluent in 1994. In successive years, these differences diminished, and in the case of the GSI no measurable difference was observed between fish exposed to the final effluent or those in the control group in 1997. However, an increase in HSI was still measurable in 1997 in fish exposed to the final effluent and at sites farther downstream. The reduction in the effects of the effluent paralleled the reduction in the concentration of nonylphenol as well as its mono- and diethoxylates, which have been demonstrated to produce estrogenic effects in trout exposed to these compounds in the laboratory. This study demonstrates that the setting of more restricted discharge limits for known estrogenic chemicals of industrial origin can lead to significant reductions in the estrogenic activity of the watercourses into which the effluents are discharged.

Gonadosomatic index (GSI) of female whitefish ( Coregonus lavaretus) in Lake Constance

From 1991 to 1997 the gonadosomatic index (GSI) of pelagic spawning female whitefish ( Coregonus lavaretus, local name “Blaufelchen”) in Lake Constance-Obersee was determined. Average GSI increased from low values in summer to a maximum of about 24% immediately before spawning (end of November/beginning of December). The coefficient of variation of GSI ranged from 14–35% of the mean in summer and autumn and decreased to values between 9 and 16% immediately before spawning. The seasonal increase in GSI was similar for all years investigated, except in 1995, when after an exceptionally mild autumn spawning took place at a water temperature of about 9.4°C. In this year, the post-August development of GSI was retarded compared to the other years of the investigation, but immediately before spawning GSI was at a value of about 24% body weight, i. e. in the same range as in the other years of the study. Despite continuing re-oligotrophication of Lake Constance no decrease in GSI was found during the study period.

SOME ASPECTS OF THE REPRODUCTION BIOLOGY OFLABEO CAPENSIS(SMITH, 1941) (PISCES, CYPRINIDAE) IN RELATION TO EXPLOITATION AND EXTREME ENVIRONMENTAL CONDITIONS IN HARDAP DAM, NAMIBIA

Summary The sex ratio of Labeo capensisdid not differ significantly at a 95% confidence level from a 1♂:1♀, ratio during the study period. The smallest sexually mature male and female L. capensis were 20 cm and 21 cm FL, respectively. Fifty percent of the males matured at 23 cm FL whereas females matured at 26 cm FL. In large ripe females (> 38 cm FL) the ovaries were as much as 15% of body mass. The males and females are two to three years old when they reach the minimum length at maturity. A linear relationship between fish mass and fecundity was obtained. The gonads of the males and females started enlarging during August, reached a peak during December to January and gradually decreased in size by February. Water temperature correlates with the development of the gonads in both male and female L. capensis, and the decrease in gonado-somatic index shows that spawning is not dependent on flooding.

Effect of dexamethasone and ACTH on oocyte growth and recruitment in the frog Rana cyanophylyctis during the prebreeding vitellogenic phase

The effects of 5, 25, 50 and 75 μg of dexamethasone and 0.1 or 0.5 IU ACTH on oocyte growth and recruitment were studied in Rana cyanophlyctis during prebreeding vitellogenic phase (May). Injections (ip) were given 6 days a week for 31 days and frogs were killed on the 32nd day. Treatment with 5 μg dexamethasone had no effect on gonadosomatic index (GSI) or on the number and percentage of different oocytes. Administration of 25 μg dexamethasone caused a significant ( P < 0.05) increase in both number and percentage of medium second growth phase (MSGP) oocytes and atretic follicles (AF), and a numerical reduction in number and percentage of large second growth phase (LSGP) oocytes. Frogs which received 50 or 75 μg dexamethasone exhibited a significant ( P < 0.05) decrease in GSI, ovarian weight, and number and percentage of LSGP oocytes, while those of MSGP oocytes and AF increased. There was no effect of dexamethasone on first growth phase (FGP) oocytes. The administration of 0.1 IU ACTH had no effect on GSI, percentage of different oocytes, or MSGP and LSGP number. There was a numerical increase in number of FGP oocytes. Treatment with 0.5 IU ACTH caused a significant ( P < 0.05) decrease in GSI, ovary weight, and number and percentage of LSGP oocytes, while those of AF increased. The above findings suggest that lower doses of dexamethasone (5 or 25 μg) and of ACTH (0.1 IU) have no effect on oocyte recruitment and growth, but that higher doses (50 or 75 μg dexamethasone and 0.5 IU ACTH) impair vitellogenic growth of oocytes and increase follicular atresia. Further, they suggest that glucocorticoids act as negative effectors on ovarian growth in R. cyanophylyctis during the prebreeding vitellogenic phase.