The Seminal Thinning Response of Carp (Cyprinus carpio) and Rainbow Trout (Salmo gairdnerii) after Injections of Pituitary Extracts

Clemens, Howard P.; Grant, F. Blake

doi:10.2307/1440720

Cited by 77 publications

(24 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Later, between weeks 6 and 12, sperm production was more closely correlated with the plasma GTH level. This agrees with data in the literature stating that gonadotropin is involved in sperm release (Clemens and Grant, 1965 ;Yamazaki and Donaldson, 1968 (Schreck, Lackey and Hopwood, 1972 ;Idler, Horne and Sangalang, 1971). Androgens could also be involved in spermiation, and high levels may be required to stimulate sperm release ( fig.…”

Section: Discussionsupporting

confidence: 92%

The spermiation period in the rainbow trout (Salmo gairdneri). Plasma gonadotropin and androgen levels, sperm production and biochemical changes in the seminal fluid

Sánchez-Rodríguez¹,

Escaffre²,

Marlot³

et al. 1978

Ann. Biol. anim. Bioch. Biophys.

View full text Add to dashboard Cite

Summary. Plasma immunoreactive t-GTH and androgens, sperm production and biochemical changes in seminal fluid were studied during the spermiation period in rainbow trout. The volume of sperm collected by hand-stripping was very low (< 0.1 ml) at the onset of spermiation, increased slowly during the next 4 weeks and sharply thereafter. Plasma t-GTH was high (6 ng/mi) at the onset and then decreased ; the sharp rise in sperm production started when circulating androgens had reached maximum values. In a second phase (b-12 weeks), the elevation in sperm production was strongly correlated wth plasma t-GTH, while plasma androgens fluctuated. Spermatocrit did not vary significantly during the period studied so that increased sperm production corresponded to an elevation in spermatozoal production. During spermiation Na + ionic concentration in the seminal fluid increased sharply and that of K + only slightly. Total protein in the seminal fluid decreased significantly after 8 weeks.Introduction.

show abstract

Section: Discussionsupporting

confidence: 92%

The spermiation period in the rainbow trout (Salmo gairdneri). Plasma gonadotropin and androgen levels, sperm production and biochemical changes in the seminal fluid

Sánchez-Rodríguez¹,

Escaffre²,

Marlot³

et al. 1978

Ann. Biol. anim. Bioch. Biophys.

View full text Add to dashboard Cite

show abstract

“…The hydration-induced increase in intratesticular pressure facilitates the movement of the spermatozoa stored in the testis to the vas deferens, thus increasing the amount of expressible milt. Therefore, a decrease in sperm density is often associated with GnRHa-or GTH-induced enhancement of milt production [62]. Although a sperm dilution was observed here in the first 4 days after GnRHa treatment, subsequently the sperm density increased to values greater than pretreatment ones.…”

Section: Discussionmentioning

confidence: 47%

Changes in Plasma Gonadotropin II and Sex Steroid Hormones, and Sperm Production of Striped Bass after Treatment with Controlled-Release Gonadotropin-Releasing Hormone Agonist-Delivery Systems1

Mylonas

Scott

Vermeirssen

et al. 1997

Biology of Reproduction

View full text Add to dashboard Cite

Spermiating striped bass, a perciform fish, were treated with two controlled-release gonadotropin-releasing hormone agonist (GnRHa)-delivery systems, and the resulting changes in plasma gonadotropin II (GTH II), testosterone (T), 11-ketotestosterone (11-KT), 17,20beta-dihydroxy-4-pregnen-3-one (17,20beta-P), and 17,20beta,21-trihydroxy-4-pregnen-3-one (17,20beta,21-P) were correlated with changes in milt production and sperm density. GnRHa-delivery systems induced a sustained elevation of plasma GnRHa and GTH II for 14 days. Plasma T levels were unchanged after GnRHa treatment, while 11-KT levels increased significantly. Plasma 17,20beta-P also increased after GnRHa treatment and remained elevated compared to levels in controls, while plasma 17,20beta,21-P levels were unaffected. Both GnRHa-delivery systems induced many-fold increases in total expressible milt, lasting throughout the 14 days of the study. Sperm density decreased 2 days after GnRHa treatment, with a subsequent increase by Day 7. This study demonstrates that GnRHa-delivery systems induce a sustained elevation of plasma GTH II levels in striped bass, resulting in a long-term enhancement of milt production. The endocrine changes observed suggest that 11-KT and 17,20beta-P, but not 17,20beta,21 -P, are mediating the effects of GTH II on spermiation.

show abstract

“…In Group A, the observed decrease was continued. The observed increase in spermatozoa concentration late in the spawning season was probably due to reduced semen dilution rather than increased sperm production (Clemens and Grant 1965;Garcia 1991;Shangguan and Crim 1999).…”

Section: Discussionmentioning

confidence: 87%

Sperm quality in male Barbus barbus L. fed different diets during the spawning season

Alavi¹,

Pšenička²,

Policar³

et al. 2009

Fish Physiol Biochem

View full text Add to dashboard Cite

Sperm quality of Barbus barbus L. was compared among the three following dietary regimes: Group A, fed 100% commercial diet (Karpico containing 33% crude protein and 6% fat), Group B, fed 78% commercial diet and 22% frozen chironomid (Chironomus plumosus) larvae, and Group C, fed 56% commercial diet and 44% frozen chironomid larvae. Concentrations of polyunsaturated fatty acids (PUFAs) in Group A, B, and C were 39.1, 42.0, and 44.6, respectively, as a percentage of total fatty acids. Sperm morphology, volume, concentration and motility, total number of spermatozoa, and osmolality of the seminal plasma were compared during the spawning season. Dietary regime did not influence sperm volume, concentration, or total number of spermatozoa, osmolality of seminal plasma, or the percentage of motile sperm, but significantly affected sperm morphology (except for anterior and posterior parts of the midpiece) and sperm velocity (P < 0.05). Groups B and C showed similar sperm characteristics during the spawning season compared to Group A. Almost all parameters changed either among or within groups during the spawning season, suggesting differences in terms of the optimal time for sperm collection. The best time for sperm collection was March for Group A, but April for Groups B and C, when the osmolality of the seminal plasma measured 289 mOsmol kg(-1) and sperm motility was maximal. Spermatogenesis, hydration, and cell decomposition were confirmed as the three major parameters controlling sperm characteristics during the spawning season. The possible correlation between sperm morphology and motility requires further study.

show abstract

The Seminal Thinning Response of Carp (Cyprinus carpio) and Rainbow Trout (Salmo gairdnerii) after Injections of Pituitary Extracts

Cited by 77 publications

References 3 publications

The spermiation period in the rainbow trout (Salmo gairdneri). Plasma gonadotropin and androgen levels, sperm production and biochemical changes in the seminal fluid

The spermiation period in the rainbow trout (Salmo gairdneri). Plasma gonadotropin and androgen levels, sperm production and biochemical changes in the seminal fluid

Changes in Plasma Gonadotropin II and Sex Steroid Hormones, and Sperm Production of Striped Bass after Treatment with Controlled-Release Gonadotropin-Releasing Hormone Agonist-Delivery Systems1

Sperm quality in male Barbus barbus L. fed different diets during the spawning season

Contact Info

Product

Resources

About