scholarly journals Dynamics of ovarian maturation during the reproductive cycle of Metynnis maculatus, a reservoir invasive fish species (Teleostei: Characiformes)

2013 ◽  
Vol 11 (4) ◽  
pp. 821-830 ◽  
Author(s):  
Thiago Scremin Boscolo Pereira ◽  
Renata Guimarães Moreira ◽  
Sergio Ricardo Batlouni
Keyword(s):  
Reproductive Cycle ◽  
Ovarian Development ◽  
Gonadosomatic Index ◽  
Ovarian Maturation ◽  
Invasive Fish ◽  
Multiple Spawning ◽  
Adult Females ◽  
The Mean ◽  
Ovulatory Follicles ◽  
Morphometric Evaluation

In this study, we evaluated the dynamics of ovarian maturation and the spawning processes during the reproductive cycle of Metynnis maculatus. Adult females (n = 36) were collected bimonthly between April 2010 and March 2011. The mean gonadosomatic index (GSI) was determined, ovarian and blood samples were submitted for morphometric evaluation and the steroid plasma concentration was determined by ELISA. This species demonstrated asynchronous ovarian development with multiple spawns. This study revealed that, although defined as a multiple spawning species, the ovaries of M. maculatus have a pattern of development with a predominance of vitellogenesis between April and August and have an intensification in spawning in September; in October, a drop in the mean GSI values occurred, and the highest frequencies of post-ovulatory follicles (POFs) were observed. We observed a positive correlation between the POF and the levels of 17α-hydroxyprogesterone. Metynnis maculatus has the potential to be used as a source of pituitary tissue for the preparation of crude extracts for hormonal induction; the theoretical period for use is from September to December, but specific studies to determine the feasibility of this approach must be conducted.

scholarly journals Mobilization of energetic substrates in the endangered catfish Steindachneridion parahybae (Siluriformes: Pimelodidae): changes in annual reproductive cycle in captivity

2018 ◽  
Vol 16 (2) ◽  
Author(s):  
Carlos E. Tolussi ◽  
Aline D. Gomes ◽  
Cristiéle da S. Ribeiro ◽  
Danilo Caneppele ◽  
Renata G. Moreira ◽  
...  
Keyword(s):  
Reproductive Cycle ◽  
Negative Correlation ◽  
Gonadosomatic Index ◽  
Reproductive Period ◽  
Annual Reproductive Cycle ◽  
Plasma Triglycerides ◽  
Glucose Levels ◽  
Adult Females ◽  
In Captivity ◽  
Continuous Feeding

ABSTRACT This study aimed at analyzing the energetic substrate (ES) in the main storage tissues of Steindachneridion parahybae, throughout the reproductive cycle in captivity. Differently from wild, in captivity, feeding is not interrupted during the reproductive period, the females do not spawn spontaneously, and they are sedentary. Adult females were sampled monthly and based on their histology and gonadosomatic index (GSI), ovaries were classified into: previtellogenic (PRV), vitellogenic (VTG), and regression (REG) stages. Ovaries at the VTG stage showed higher protein and lipids levels than at the PRV stage with a positive correlation between these substrates and the GSI. Muscle was the main source of proteins transferred to the ovaries, according to the negative correlation between these organs. Lipids remained unchanged in the liver, which is an important supplier in vitellogenesis, a pattern that probably occurs due to the continuous feeding. Muscular glycogen levels were higher at the VTG and REG than at the PRV stages. Plasma triglycerides were also higher during REG, while glucose levels were more elevated during the VTG stage. These results suggest that with constant food supply, the pattern of deposition of ES in S. parahybae is different from that described for other wild potamodromous species.

Monthly variations in the profile of sex steroids and ovarian development of brook trout (Salvelinus fontinalis Mitchill) during the annual reproductive cycle in Tasmania

2015 ◽  
Vol 63 (3) ◽  
pp. 220 ◽  
Author(s):  
Shafaq Fatima ◽  
Mark Adams ◽  
Ryan Wilkinson
Keyword(s):  
Reproductive Cycle ◽  
Sex Steroids ◽  
Brook Trout ◽  
Ovarian Development ◽  
Gonadosomatic Index ◽  
Annual Reproductive Cycle ◽  
Total Fecundity ◽  
Mature Fish ◽  
Index Value ◽  
Monthly Variations

Control of maturation in all-female salmonid stock can be achieved by manipulating photoperiod. This initially requires an assessment of the annual reproductive cycle under ambient photoperiod. This study therefore describes the seasonal variations in ovarian development and plasma profiles of oestradiol-17β and testosterone during the second year of a population of female brook trout. It was found that fish recruited for maturation following the summer solstice in December. Shortening of photoperiod likely stimulated the brain–pituitary–gonadal axis for vigorous progress of ovarian development, as indicated by increasing levels of oestradiol-17β and gonadosomatic index values. The highest gonadosomatic index value (18.26 ± 1.1%) was observed in June. During July, eggs were released from mature females by manual stripping. Total fecundity was observed as 4266 ± 341 oocytes per mature fish. Profiles of sex steroids observed here were found to be finely entrained within the succession of seasonal photoperiod. This finding indicates that maturation suppression by photoperiod manipulation should be instigated before initiation of oocyte recruitment that commenced during December.

The ovarian development pattern of pond-reared Chinese mitten crab, Eriocheir sinensis H. Milne-Edwards, 1853

Crustaceana ◽  
2017 ◽  
Vol 90 (4) ◽  
pp. 449-470 ◽  
Author(s):  
Xugan Wu ◽  
Meimei Liu ◽  
Jie Pan ◽  
Hao Chen ◽  
Chaoshu Zeng ◽  
...  
Keyword(s):  
Ovarian Development ◽  
Gonadosomatic Index ◽  
Eriocheir Sinensis ◽  
Stage Iii ◽  
Development Pattern ◽  
Hepatosomatic Index ◽  
Ovarian Maturation ◽  
Chinese Mitten Crab ◽  
Mitten Crab ◽  
Ovarian Morphology

Although pond culture is the major culture method for Chinese mitten crab (Eriocheir sinensis) in China, the pattern of ovarian development in pond-rearedE. sinensisremains unclear. This study investigated the changes in ovarian morphology and histology, gonadosomatic index (GSI), hepatosomatic index (HSI), and monthly variation of the ovarian development pattern during the ovarian maturation of pond-reared femaleE. sinensis. Based on the pubertal moult, and ovarian morphology and histology, the ovarian development cycle ofE. sinensiscould be divided into five stages, i.e., Stage I: the ovary appears thin ribbon-like and translucent, dominated by oogonia (OG) and previtellogenic oocytes (PRO); Stage II: the ovary appears milk white or buff, dominated by endogenous vitellogenic oocytes (EN); Stage III: the ovary appears orange or light brown, dominated by exogenous vitellogenic oocytes (EX); Stage IV: the ovary appears crimson red or brown and ovarian lobes occupy most available body cavities. The major oocytes were nearly mature oocytes (NO); Stage V: the ovary appears deep purple and is filled with mature oocytes (MO). During ovarian maturation, the GSI increased significantly and a significant, positive correlation was found between the GSI and the mean long diameter of the oocyte from stage III to stage V. However, a significantly negative correlation was found between GSI and HSI. The ovarian development of pond-reared femaleE. sinensiswas not synchronous, most of the pubertal moults were found until mid-late August. At the end of August, the percentages of females that reached ovarian stages II and III were 55 and 24%, respectively. After that, the ovarian development of pond-reared femaleE. sinensisbecame fast, and females with stage III or more advanced ovaries were found to be in excess of 80% by the end of September and onward. From the end of November to late December, the GSI of femaleE. sinensisdid not increase significantly, which indicated pond-reared females had reached mature or nearly-mature ovaries by the end of November.

Temperature-Regulated Changes in the Ovaries of Overwintering Females of the Queensland Fruit Fly, Dacus Tryoni.

1975 ◽  
Vol 23 (1) ◽  
pp. 91 ◽  
Author(s):  
BS Fletcher
Keyword(s):  
Ovarian Development ◽  
New South ◽  
New South Wales ◽  
Fruit Fly ◽  
Ovarian Maturation ◽  
Developmental Threshold ◽  
South Wales ◽  
The Mean ◽  
Central Eastern

Changes in the ovaries of overwintering D. tryoni females at two localities in central eastern New South Wales were studied during 1969 and 1970. In the ovaries of females from both locations, new follicles were differentiated throughout the winter months but most of them were later resorbed. By the end of the winter most females had at least two and some as many as four resorbed follicles per ovariole. The most advanced follicle in the ovariole was resorbed first, except in ovarioles where mature eggs were present, when the penultimate follicle was the first to be resorbed. In a high proportion of the mated parous females the sperm disappeared from the spermathecae when all the viable mature eggs had been laid. Comparison between the changes in the median stages of ovarian development and the tempera- ture data for the same period indicated that it was the mean number of day-degrees above the developmental threshold (13.5�C) experienced by the females which determined whether the ovaries continued to mature or not. Ovarian maturation continued while the mean number of day-degrees stayed above 1.6 and resorption occurred when it dropped below this. However, when the mean number of day-degrees dropped much below unity the ovaries showed very little change either way. The possible causes of ovarian resorption during the winter months and its possible significance for the survival of the flies is discussed.

Dynamics of fatty acid regulatory genes during ovarian development in Penaeus monodon

Reproduction ◽  
2018 ◽  
Author(s):  
Pacharawan Deenarn ◽  
Punsa Tobwor ◽  
Rungnapa Leelatanawit ◽  
Somjai Wongtriphop ◽  
Jutatip Khudet ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Ovarian Development ◽  
Penaeus Monodon ◽  
Chain Fatty Acid ◽  
Regulatory Genes ◽  
Ovarian Maturation ◽  
Long Chain Fatty Acid ◽  
Eyestalk Ablation ◽  
Regulatory Pathways ◽  
Expression Levels

The delay in ovarian maturation in farmed black tiger shrimp Penaeus monodon has resulted in the widespread practice of feeding broodstock with the polychaetes Perinereis nuntia and their unilateral eyestalk ablation. Although this practice alters fatty acid content in shrimp ovaries and hepatopancreas, its effects on fatty acid regulatory genes have yet to be systematically examined. Here, microarray analysis was performed on hepatopancreas and ovary cDNA collected from P. monodon at different ovarian maturation stages, revealing that 72 and 58 genes in fatty acid regulatory pathways were differentially expressed in hepatopancreas and ovaries respectively. Quantitative real-time PCR analysis revealed that ovarian maturation was associated with higher expression levels of acetyl-CoA acetyltransferase, acyl-CoA dehydrogenase, acyl-CoA oxidase 3 and long-chain fatty acid transport protein 4 in hepatopancreas, whereas the expression levels of 15 fatty acid regulatory genes were increased in shrimp ovaries. To distinguish the effects of different treatments, transcriptional changes were examined in P. monodon with stage 1 ovaries before polychaete feeding, after one-month of polychaete feeding and after eyestalk ablation. Polychaete feeding resulted in lower expression levels of enoyl-CoA hydratase and acyl-CoA synthetase medium-chain family member 4, while the expression level of phosphatidylinositide phosphatase SAC1 was higher in shrimp hepatopancreas and ovaries. Additionally, eyestalk ablation resulted in a higher expression level of long-chain fatty acid-CoA ligase 4 in both tissues. Together, our findings describe the dynamics of fatty acid regulatory pathways during crustacean ovarian development and provide potential target genes for alternatives to eyestalk ablation in the future.

scholarly journals Comparative study of colour Doppler vs. FNNAC findings in WHO grade II thyroid enlargement in adult females

2019 ◽  
Vol 5 (4) ◽  
pp. 1025
Author(s):  
Sudhakar Rao M. S. ◽  
Navneeth T. P. ◽  
John C. J.
Keyword(s):  
Pulsatility Index ◽  
Low Cost ◽  
Resistive Index ◽  
Colour Doppler ◽  
Who Grade ◽  
Predictive Values ◽  
Non Invasive ◽  
Adult Females ◽  
The Mean ◽  
Sensitivity Specificity

<p class="abstract"><strong>Background:</strong> Thyroid gland disorders form one of the most common endocrinal and surgical problems encountered in clinical practice. FNNAC is widely accepted as the primary and better method than FNAC for investigation but has its disadvantages. Colour Doppler is a non-invasive, low cost, easily available and repeatable investigation with least patient discomfort and can be valuable in detection of benign and malignant thyroid enlargements.</p><p class="abstract"><strong>Methods:</strong> Forty cases of adult females with WHO grade 2 thyroid enlargement attending the department of otorhinolaryngology selected on simple random basis were included in this study. Following written consent, Colour Doppler scanning and FNNAC test were done on the thyroid swelling and the results were analysed.  </p><p class="abstract"><strong>Results:</strong> The mean age of patients was 32.44 years. The mean age of malignancy was 44.66 years and showed statistically significant association. The Resistive and Pulsatility index and combination of both were found to have statistically significant results in detecting malignant and benign lesions The sensitivity, specificity, positive and negative predictive values of RI and PI were 83.33%, 94.12%, 71.43%, 96.97% and 50%, 94.12%, 60% and 91.43% respectively. On combining both the indices, the sensitivity was 91.67% and the positive predictive value was 97.06%.</p><p class="abstract"><strong>Conclusions:</strong> Colour Doppler can differentiate between benign and malignant thyroid enlargements using Resistive index (of&gt;0.75) and Pulsatility Index (of&gt;1.5) and can be a complementary diagnostic tool in the thyroid enlargement lesions, considering its accuracy, cost-effectiveness, easy availability and non-invasive repeatable nature.</p>

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