Oogenesis and ovarian development cycle of the spiny lobster Panulirus japonicus (Decapoda:Palinuridae)

Oogenesis and ovarian development in female Panulirus japonicus were examined by light and electron microscopy. Eight substages (oogonium, bouquet, chromatin nucleolus, oil globule, pre-yolk platelet, yolk platelet, pre-maturation and maturation) were distinguished in the typical process of oogenesis (multiplication, pre-vitellogenesis, vitellogenesis and maturation stages). Yolk accumulation started at the late pre-yolk platelet substage, when electron-dense granules appeared. Yolk granules seemed to be accumulated in two ways, being produced endogenously by the abundant rough endoplasmic reticulum during vitellogenesis and exogenously by micropinocytosis from the yolk platelet to pre-maturation substages. Ovulation occurred after oocytes became mature (i.e. after the metaphase of the primary maturation division was reached). The diameter of mature oocytes was 465–477 µm. The seasonal ovarian development cycle was divided into seven stages: inactive, developing, ripe, re- developing, re-ripe, spawned and recovery. The morphological characteristics relating to the gonadosomatic index (GSI) of each stage are described (GSI was calculated by the formula I = W × 105/L3, where I represents GSI, W is the gonad weight in grams, and L is the carapace length in millimetres). Estimated GSI values ranged from 11.3 to 12.4 in individuals with mature oocytes, and the 99% confidence intervals for GSI values of adjacent oogenesis substages did not overlap. GSI values at the developing and ripe stages were significantly larger than those at the re-developing and re-ripe stages, respectively.

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Effects of photoperiod and temperature on ovarian development and spawning of the Japanese spiny lobster Panulirus japonicus

Aquaculture ◽

10.1016/s0044-8486(01)00687-1 ◽

2002 ◽

Vol 205 (3-4) ◽

pp. 385-398 ◽

Cited By ~ 27

Author(s):

Hirokazu Matsuda ◽

Taisuke Takenouchi ◽

Takashi Yamakawa

Keyword(s):

Ovarian Development ◽

Spiny Lobster ◽

Panulirus Japonicus

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An Electron Microscope Study of Basophile Substances of Frozen-Dried Rat Liver

The Journal of Cell Biology ◽

10.1083/jcb.4.3.291 ◽

1958 ◽

Vol 4 (3) ◽

pp. 291-300 ◽

Cited By ~ 25

Author(s):

Henry Finck

Keyword(s):

Electron Microscopy ◽

Electron Microscope ◽

Rat Liver ◽

Microscope Study ◽

Electron Microscope Study ◽

Freeze Drying ◽

Light And Electron Microscopy ◽

Enzyme Treatment ◽

Dense Granules ◽

Homogeneous Matrix

Small pieces of liver from rats subjected to different dietary regimes were fixed by freeze-drying, and postfixed by in vacuo heating and denaturation with alcohol. Specimens were digested with ribo- or deoxyribonuclease, and stained with gallocyanin-chromalum, azure II, the Feulgen procedure or alcoholic platinic tetrabromide. Some specimens were reserved as controls of the effects of enzyme treatment. Stained and unstained specimens were embedded in methacrylate and examined by light and electron microscopy. Basophilic and Feulgen-positive substances, after contact with watery reagents, were found by electron microscopy to exist as small dense granules embedded in a less dense homogeneous matrix, forming the walls of submicroscopic vacuoles. These granules were absent after digestion with nucleodepolymerases. In specimens (unstained, or stained with platinic tetrabromide) which had not passed through water, the dense (basophile) substances in nuclei and cytoplasm were found to exist, not as granules, but as ill defined submicroscopic concentrates which blended imperceptibly into the homogeneous matrix of the vacuolar walls. Objections to the use of stains for improving contrast conditions in electron microscopy of tissues are discussed, and it is concluded that the reagents do not necessarily produce the observed increases in contrast by selectively stabilizing certain structures. The concept of microsomes as pre-existing distinct morphological entities in intact (unhomogenized) cells is thought to be inconsistent with the distribution of basophile substances in frozen-dried liver.

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Reproductive period and fecundity of Serrapinnus piaba (Characidae: Cheirodontinae) from the rio Ceará Mirim, Rio Grande do Norte, Brazil

Neotropical Ichthyology ◽

10.1590/s1679-62252003000100007 ◽

2003 ◽

Vol 1 (1) ◽

pp. 61-66 ◽

Cited By ~ 12

Author(s):

Jacira Silvano ◽

Cristina L. C. Oliveira ◽

Clarice B. Fialho ◽

Hélio C. B. Gurgel

Keyword(s):

Gonadosomatic Index ◽

Rio Grande ◽

Total Body Weight ◽

Mature Female ◽

Reproductive Period ◽

Day Length ◽

Maturation Stages ◽

Total Body ◽

Spearman Test ◽

Test Correlation

Specimens of Serrapinnus piaba were collected monthly from April 2001 to April 2002 in the rio Ceará Mirim, Rio Grande do Norte State, Brazil. The reproductive period, determined through the monthly variation of the gonadosomatic index (GSI) and maturation stages, occurred from January to April. Non-parametric Spearman test was performed in order to test correlation of monthly GSI variation in males and females with water temperature, rainfall and day length. Rainfall and Temperature were correlated with GSI variation in females only and day length showed a negative correlation with GSI variation of males only. It was verified the presence of hooks on the anal fin of mature and maturing males along all the period of study. The absolute fecundity mean was 441 (±178.08) oocytes, determined by the number of yolky oocytes counted in 27 mature female gonads. The relative fecundity, estimated by the number of yolky oocytes divided by milligram of total body weight was 0.74 (± 0.19).

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Effects of Photoperiod on Epididymal and Sperm Morphology in a Wild Rodent, the Viscacha (Lagostomus maximus maximus)

ISRN Anatomy ◽

10.5402/2013/128921 ◽

2013 ◽

Vol 2013 ◽

pp. 1-10 ◽

Cited By ~ 5

Author(s):

A. M. Cruceño ◽

J. C. de Rosas ◽

M. Fóscolo ◽

E. M. Chaves ◽

L. Scardapane ◽

...

Keyword(s):

Electron Microscopy ◽

Reproductive Cycle ◽

Sperm Morphology ◽

Structural Parameters ◽

Light And Electron Microscopy ◽

Morphological Characteristics ◽

Activity Period ◽

Epididymal Sperm ◽

Wild Rodent ◽

Lagostomus Maximus

The viscacha (Lagostomus maximus maximus) is a seasonal South American wild rodent. The adult males exhibit an annual reproductive cycle with periods of maximum and minimum gonadal activity. Four segments have been identified in the epididymis of this species: initial, caput, corpus, and cauda. The main objective of this work was to relate the seasonal morphological changes observed in the epididymal duct with the data from epididymal sperm during periods of activity and gonadal regression using light and scanning electron microscopy (SEM). Under light and electron microscopy, epididymal corpus and cauda showed marked seasonal variations in structural parameters and in the distribution of different cellular populations of epithelium. Initial and caput segments showed mild morphological variations between the two periods. Changes in epididymal sperm morphology were observed in the periods analyzed and an increased number of abnormal gametes were found during the regression period. During this period, anomalies were found mainly in the head, midpiece, and neck, while in the activity period, defects were found only in the head. Our results confirm that the morphological characteristics of the epididymal segments, as well as sperm morphology, undergo significant changes during the reproductive cycle of Lagostomus.

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Reproduction and population structure of the sea cucumber Holothuria tubulosa in the Dardanelles Strait, Turkey

Mediterranean Marine Science ◽

10.12681/mms.1360 ◽

2015 ◽

Vol 17 (1) ◽

pp. 47 ◽

Cited By ~ 3

Author(s):

H. DERELİ ◽

S. TÜRK ÇULHA ◽

M. ÇULHA ◽

B. H. ÖZALP ◽

A. A. TEKİNAY

Keyword(s):

Population Density ◽

Gonadosomatic Index ◽

Morphological Characteristics ◽

Environmental Parameters ◽

Population Characteristics ◽

High Positive Correlation ◽

Mediterranean Populations ◽

Reproductive Patterns ◽

First Time ◽

The Relationship

In this study, Holothuria tubulosa Gmelin 1791 was investigated from April 2013 to March 2014 in the Dardanelles Strait, to outline the morphological characteristics, reproductive patterns and the relationship between population characteristics and environmental parameters. Between 15 and 30 individuals of this species were sampled monthly from three stations. There was a negative allometry between length and weight, being gutted weight the most reliable measurement for this species. Reproductive patterns of the species were identified the first time for Turkish coasts. By macroscopic examination of the gonads, smallest sizes (gutted length) were measured as 8.4 and 8.1 cm for female and male, respectively. Sex ratio was calculated as 1: 1.1 with differences between seasons. The reproduction of sea cucumbers occurred between August and September after Gonadosomatic Index (GSI) values reached their maximum in July. The species was found down to 10 m depth with a population density of 0.21 / m2, which was rather low compared to previously reported values for Mediterranean populations of this species. There was a high positive correlation between population density and GSI of the species. The highest population density was observed where the largest sea grass meadows are found.

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Recent findings in oogenesis of Drosophila melanogaster

Development ◽

10.1242/dev.39.1.45 ◽

1977 ◽

Vol 39 (1) ◽

pp. 45-57

Author(s):

F. Giorgi ◽

J. Jacob

Keyword(s):

Drosophila Melanogaster ◽

Acid Phosphatase ◽

Ovarian Development ◽

Superficial Layer ◽

Blood Proteins ◽

Selective Hydrolysis ◽

Internal Lining ◽

Hydrolysis Of ◽

Zinc Iodide ◽

Yolk Platelet

The role played by the vitellogenic oocytes of Drosophila melanogaster in relation to the elaboration of material taken from the haemolymph is examined by ultrastructural cytochemistry. As revealed by the Gomori procedure, acid phosphatase occurs widely over the forming yolk platelets of the cortical and central ooplasm. A number of Golgi apparatuses in thecortical ooplasm are also positively stained with lead precipitates. With the proceeding of the ovarian development it becomes progressively more difficult to demonstrate cytochemically the enzyme over the yolk platelets. In stage 9–10 chambers the acid phosphatase is restricted to the so-called associated body, while the rest of the yolk platelet appears devoid of lead deposits. By using a osmium zinc iodide (OZ1) complex as a preferential staining method for the Golgi apparatus, it has been shown that, apart from the apparatus itself, a number of OZI deposits occur over the superficial layer of the forming yolk platelets. When mature yolk platelets are formed at later stages, the OZI deposits in the yolk platelets come to be restricted to the cap-like region of the superficial layer which contains the associated body. In vitellogenic oocytes, both the internal lining of the limiting membrane of the forming yolk platelets and the associated body of the mature yolk platelets react positively, to cytochemical methods to demonstrate carbohydrates. The present findings are interpreted as indicating the involvement of lysosomal enzymes in the process of maturation of the yolk material. The suggestion is also made that such an involvement is required to accomplish a selective hydrolysis of those blood proteins which have been taken in by vitellogenic oocytes along with yolk precursors.

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Reproductive indicators of the endemic species Astyanax bifasciatus (Teleostei: Characidae) in a tributary of the Lower Iguaçu River Basin, Brazil

Acta Scientiarum Biological Sciences ◽

10.4025/actascibiolsci.v41i1.47720 ◽

2019 ◽

Vol 41 ◽

pp. e47720

Author(s):

Elton Celton de Oliveira ◽

Alexandre Augusto Auache-Filho ◽

Denis Damasio ◽

Nédia de Castilhos Ghisi ◽

Maria Antônia Michels-Souza

Keyword(s):

River Basin ◽

Fish Species ◽

Sexual Maturity ◽

Gonadosomatic Index ◽

Reproductive Period ◽

Maturity Stage ◽

Reproductive Process ◽

Maturation Stages ◽

High Degree ◽

Iguaçu River

The reproductive process promotes morphophysiological and behavioral changes in fish species throughout their life cycle. Its success is vital to define their resilience in the environment. This study aimed to evaluate the reproductive biology of the endemic fish species Astyanax bifasciatus in a tributary of the Lower Iguaçu River Basin, Paraná, Brazil. Fish were collected monthly at four sites along the Jirau Alto River in the city of Dois Vizinhos from October 2015 to September 2016. A standardized catch effort with gill nets and fish traps was used. In the laboratory, standard length and total weight were recorded. After anesthesia, the animals were sectioned to macroscopically determine the sex, sexual maturity stage, and presence of celomatic fat. The gonads and liver were removed to determine the gonadosomatic and hepatosomatic indexes, respectively. A total of 160 individuals (104 females and 56 males) were used. The gonadosomatic index, frequency of the gonadal maturation stages, and condition factor showed a long reproductive period with two investment cycles for both sex. Length at first sexual maturity was 4.57 cm for females and 3.56 cm for males. The reproductive data corroborate the generalist profile of the species and demonstrate a high degree of adaptive capacity, even in smaller tributaries.

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