Histological study on the gonadal development of Scatophagus argus

2013 ◽  
Vol 37 (5) ◽  
pp. 696 ◽  
Author(s):  
Dan CUI ◽  
Zhiwei LIU ◽  
Nanxi LIU ◽  
Yingying ZHANG ◽  
Junbin ZHANG
Keyword(s):  
Histological Study ◽  
Gonadal Development ◽  
Scatophagus Argus

scholarly journals Histological study of the developing gonads of endangered freshwater spiny eel, Mastacembelus armatus during the reproductive cycle

2017 ◽  
Vol 14 (2) ◽  
pp. 261-269 ◽  
Author(s):  
MR Ali ◽  
MM Rahman ◽  
MRI Sarder ◽  
MFA Mollah
Keyword(s):  
Reproductive Cycle ◽  
Histological Analysis ◽  
Developmental Stages ◽  
Histological Study ◽  
Gonadal Development ◽  
Yolk Granule ◽  
Immature Stages ◽  
Reproductive Condition ◽  
Nutritive Values ◽  
Mastacembelus Armatus

The spiny eel, Mastacembelus armatus is one of the most common and economically important inland teleost species of Asia having high market and nutritive values. The demand for the fish is almost always exceeds its supply. Histological analysis of developmental stages of both oocytes and sperrnatocytes maturation were undertaken and dimensions of ovarian oocytes were observed to evaluate the annual reproductive condition of M. armatus during August 2012 to July 2013. Monthly sampling of adult individuals of M. armatus was done from haor region of Kishoreganj district, Bangladesh. Both the gonads were paired, elongated and of unequal in length. The colour of ovaries varied from reddish brown to light yellowish; whereas, testes varied from whitish to creamy or dull white. From the histological study, five stages of oocyte development (oogonia, chromatin nucleolar stage oocyte, perinucleolar stage oocytes, yolk vesicle oocyte, and yolk granule stage) were observed upon their changes in nucleus. Female M. armatus having immature stages of oocytes (early and late perinucleolar stage oocytes) were mostly available in the months of November and December. Yolk vesicle stage oocytes appeared during the months of January and February. Early yolk granule stage oocytes appeared during the months of March and April while late yolk granule stage oocytes were observed during the months of May and June. Oocytes and nuclei diameters were observed ranged from 12–1050 ?m and 10–212 ?m, respectively until ovulation. In male gonads, four stages of spermatogenesis (spermatogonia, spermatocytes, spermatids, and spermatozoa) were distinguished during the study period where spermatids were prominent in January to March and spermatozoa in April to July. From this study, the peak gonadal development of M. armatus is found in June and thus, it is clearly indicated that the fish breed during May to June.J. Bangladesh Agril. Univ. 14(2): 261-269, December 2016

Histological study of gonadal development and sex differentiation in Salvelinus fontinalis under Tasmanian climate conditions

2011 ◽  
Vol 59 (5) ◽  
pp. 321 ◽  
Author(s):  
Shafaq Fatima ◽  
Mark Adams ◽  
Ryan Wilkinson
Keyword(s):  
Brook Trout ◽  
Developmental Process ◽  
Histological Study ◽  
Sex Differentiation ◽  
Gonadal Development ◽  
Degree Days ◽  
Climate Conditions ◽  
Androgen Treatment ◽  
Stromal Tissue ◽  
Steroidogenic Cells

This study describes the developmental process of gonads in brook trout from 0 degree days post-hatch (°dph) until completion of sex differentiation (3354°dph). Gonadal development was divided into undifferentiated (0–2013°dph) and differentiated phases (2769–3354°dph). Fertilised eggs (n = 1000) were incubated at 9.5−10°C until hatching at 66 days post-fertilisation (dpf). A total of 20% of alevins sampled on 0°dph were found with unpaired and undifferentiated gonads, indicating that gonadal development commenced before hatch. Initially, undifferentiated gonads contained stromal tissue and few primordial gonadal cells (PGC) (n = 2–5). During the undifferentiated phase, gonads increased in size and proliferative activity of the PGC increased their number (n = 15–22). The differentiated phase commenced with the appearance of sex differentiation at 2769°dph where gonads could be clearly differentiated as ovaries and presumptive testes. Ovaries were identified by the presence of oogonia while presumptive testes contained spermatogonia, vena comittis and a proximal network of cavities. Both ovaries and testes underwent further differentiation until the end of this phase (3354°dph). Oogonia were transformed into primary oocytes while spermatogonial cysts were observed in testes. However, differentiation of steroidogenic cells could not be observed. Direct sex differentiation was found in this study as undifferentiated gonads directly developed into testes and ovaries with anatomical differentiation preceding cytological differentiation. This study confirms previous studies that the prehatch period should be targeted when attempting to produce future monosex populations via indirect sex reversal using androgen treatment.

Histological Study of Human Thyroid Gland Relative Proportion of Parenchyma and Stroma in Thyroid Glands of Bangladeshi People

2013 ◽  
Vol 1 (2) ◽  
pp. 17-20
Author(s):  
Md Enayet Ullah ◽  
Hasna Hena ◽  
Rubina Qasim
Keyword(s):  
Thyroid Gland ◽  
Histological Study ◽  
Relative Proportion ◽  
Age Groups ◽  
Human Thyroid ◽  
Structural Units ◽  
Thyroid Glands ◽  
Group A ◽  
Group B ◽  
Connective Tissue Sheath

Deep cervical fascia forms a connective tissue sheath around the thyroid gland. Delicate trabeculae and septa penetrate the gland indistinctly dividing the gland into lobes and lobules which in turn composed of follicles.1,2,3 These follicles are structural units of thyroid gland which varies greatly in size and shape.4 The number of follicles varies in different age groups. The study was carried out to see the percentage of area occupied by follicles in the stained section of thyroid glands in different age groups. The collected samples were grouped as A (3.5 – 20yrs), B (21- 40yrs) & C (41 – 78yrs). Percentage of area occupied by follicles was (58.55±10.72) in group A, (63.79±12.35) in group B + (63.39±8.29) in group C.DOI: http://dx.doi.org/10.3329/updcj.v1i2.13981 Update Dent. Coll. j. 2011: 1(2): 17-20

ANATOMICAL AND HISTOLOGICAL STUDY OF CEREBRAL IN STURNUS VULGARIS

2013 ◽  
Vol 12 (2) ◽  
pp. 221-227 ◽  
Author(s):  
A Ali ◽  
Sawsan A ◽  
Faleha. H aziz ◽  
Nathum .A.Shehan ◽  
Samira .A.Dhage
Keyword(s):  
Histological Study ◽  
Sturnus Vulgaris
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