Common Carp Pituitary Extract Research Articles

Induced Spawning of Grass Carp Ctenopharyngodon idella, Using Common Carp Pituitary Extract with Domperidone

To test the efficacy of the technique of using dopamine antagonists with pituitary extracts, experiments were conducted in July, 2022, at Masab Al Sen (Al Sen estuary) Fish Farm and Hatchery, General Commission for Fisheries Resources, Syria. In all, 18 sets (2 female x 4 male in each set) were tried individually. 9 sets were treated with domperidone (DOM) and carp pituitary extract (CPE) and they constituted the experimental sets, while the rest 9 were treated with CPE and formed the control sets. The ovulation ratio, absolute fecundity, relative fecundity (number of eggs/kg), fertilization rate and hatching rate was 92.85%, 384645 ± 70990 eggs, 56853.22 ± 5385.68 eggs/kg, 80.02% and 61.54%, respectively in the experimental sets whereas it was 92.85%, 355172 ± 53008 eggs, 52059.73 ± 3853.71 eggs/kg, 72.50% and 54.46% respectively in case of control sets. Hatching occurred within 20 h and 45 min to 21 h after fertilization in the experimental sets whereas it was 20 h and 45min to 21 h and 20 min in case of control sets at 26-26.5°C. It was observed that body weight has positive influence on absolute fecundity (r = 0.98, 0.99) and relative fecundity (0.97,0.97) in case of experimental sets and control sets respectively.

Propagation of jundia Rhamdia quelen (Siluriformes: Heptapteridae) by applying the ovarian sperm injection method

We compared the effectiveness of the ovarian sperm injection method with that of the traditional one over the artificial propagation of jundia. Three experimental groups were set up containing seven females each. Females in Group 1 received common carp pituitary extract (CPE) homogenized in saline to induce ovulation and the stripped eggs were fertilized with the traditional dry method. In Group 2 ovulation was induced as in Group 1, however, sperm for fertilization was injected to the ovarian cavity of the females. In Group 3, CPE was first homogenized in sperm which was then injected to the ovarian cavity of females. All females received the same dose of 5.0 mg kg−1 bodyweight. Females in Group 2 and 3 were inseminated by a catheter. To fertilize the eggs, sperm samples were pooled from six males and they were used for all groups. There were no significant differences among the three Groups (P < 0.05) in the investigated parameters, such as ovulation ratio, pseudo-gonadosomatic index and fertilization rate. Our results demonstrated that the effectiveness of the sperm injection method was similar to that of the traditional one.

Retracted : Effectiveness of carp pituitary extract and luteinizing hormone releasing hormone analogue administration (by either injection or cholesterol pellet implantation) on spawning performance in female sturgeon, Huso huso

The effectiveness of common carp pituitary extract (CPE), luteinizing hormone releasing hormone analogue (LHRH-A2) injections and LHRH-A2 implants for spawning induction in female sturgeon, Huso huso was examined. In the first trial, fish were injected with 7% physiological saline (control), 50 mg kg−1 CPE or LHRH-A2 at 3.5, 7, 8 or 10 μg kg−1. In the second trial, fish were treated with LHRH-A2 cholesterol pellet implants containing 0, 3.5, 7, 8 and 10 μg kg−1 LHRH-A2. Ovulated eggs were removed using a minimally invasive surgical technique and were artificially fertilized. Injection of CPE and LHRH-A2 at doses of 3.5, 7, 8 and 10 μg kg−1 resulted in the number of ovulated fish more than LHRH-A2 implants (similar doses) or controls, although there was no significant difference at doses of 8 and 10 μg kg−1 (P ≥ 0.05). The latency period of fish receiving CPE and LHRH-A2 injections was approximately 20 h, which was significantly lower than in fish receiving LHRH-A2 implants (P ≤ 0.05). Furthermore, there were no significant differences in rates of fertilization or hatching among the progeny produced in any of the treatment groups (P ≥ 0.05). In conclusion, the data from this study could be useful for artificial propagation of not-fully-matured females of H. huso at sturgeon hatcheries.

Initial development of Prochilodus hartii (Pisces: Prochilodontidae) submitted to induced reproduction.

The Prochilodontidae prepare for reproduction in captivity, but neither ovulation nor spawning occurs, thus requiring induced reproduction for breeding and restocking. This study analyzed for the first time the embryogenesis and larval ontogeny of P. hartii submitted to induced reproduction by hypophysation with crude common carp pituitary extract. The extrusion of oocytes and sperm was performed manually and fertilization was done using the dry method. After fertilization, the eggs were kept in incubators at 23°C. A stereomicroscope was used to measure egg diameter and to monitor embryo development. Samples of larvae were collected daily for 7 days for histological and biometric analyses. The recently extruded oocytes, non-hydrated, are spherical, grey, and non-adhesive with a diameter of 1480 ± 39 μm and after hydration, have a diameter of 2860 ± 120 μm. The positive response to hypophysation was 100% for females and 80% for males. Spawning occurred 7 h after the third hormonal dosage. The fertilization rate was 77% at 23°C. Blastopore closure occurred at 6 h 45 min and embryonic development was completed 36 h 10 min after fertilization. After 204 h post fertilization (hpf) the larvae reached a standard length of 6.56 ± 0.14 mm with the yolk sac completely resorbed. In P. hartii, the oral cavity opening occurred 132 hpf. The results of this study provide knowledge to better understand induced reproduction, breeding, and management of P. hartii, a species with a high potential for pisciculture, and which is commercially important in the Jequitinhonha River basin.

Spawning induction in Kutum, Rutilus frisii kutum (Kamensky), with different hormones: Analysis of hormone profiles and induced spawning success

The objective of this study was to evaluate the effectiveness of different hormones on spawning success and sex steroid changes in Caspian Kutum, Rutilus frisii kutum. Groups of five fish were injected intramuscularly as follows: 2 mg kg -1 common carp pituitary extract (CPE) as the positive -1 human chorionic gonadotropin (hCG), 2 μg kg -1 luteinizing hormone releasing hormone analog (LHRHa2), 10 μg kg -1 synthetic analogue gonadoliberins (sGnRHa), 0.2 mL kg -1 Ovaprim which is a complex of salmon GnRH analogue with a dopamine receptor antagonist (domperidone), a combination of 2 μg kg -1 LHRHa2 and 100 IU kg -1 hCG, a complex of 10 μg kg -1 sGnRHa and 100 hCG IU kg -1 , and saline solution as the negative control. Blood samples were taken simultaneously with injections and after ovulation. The results showed that no fish ovulated in the negative control group. In the CPE treatment group, 4 of 5 fish ovulated. In the other experimental groups; no response was observed in the hCG group, while the females injected with sGnRHa-alone, LHRHa2-alone, and sGnRH+hCG had low spawning percentages. Of the hormones tested, the combination of sGnRHa+domperidone was the most effective spawning inducer and the greatest spawning success was obtained. Significant decreases after injection were observed in plasma concentrations of 17â estradiol, 17a-hydroxy progesterone, and progesterone in all treatments, while plasma testosterone concentrations increased significantly. This study revealed that a combined sGnRHa and dopamine antagonist can improve the effectiveness of artificial reproduction of Kutum. Since the combination of sGnRHa and domperidone is purer than CPE and has the most effective in inducing ovulation, it is preferred for inducing spawning in this species.

Effects of hormonal manipulation on stress responses in male and female broodstocks of pikeperch Sander lucioperca

This study was designed to determine the effects of hormonal manipulation on stress responses in female and male pikeperch. Two-year-old cultured female and male broodstocks with an average weight of 337.4 ± 20.1 (mean ± SE; n = 16) and 318.7 ± 15.1 g (n = 16), respectively, were randomly allocated into four hormonal treatments each containing 4 fish. Two sexual groups of 16 fish for each gender were considered. Sexually mature male and female pikeperch were injected with either physiological saline solution (as control group), common carp pituitary extract (CPE), human chorionic gonadotropin (hCG) and or luteinizing hormone-releasing hormone analog (LHRHa2). The blood samples were taken before hormonal injection and after ovulation and spermiation. Then the plasma levels of stress indices (cortisol, glucose, and lactate) were determined. The results showed that all CPE-, HCG-, and LHRHa2- injected males produced sperm. In females treated with CPE and hCG, three of four ovulated, but none of LHRHa2- and saline-injected fish spawned. Significant changes in cortisol, glucose, and lactate levels were observed among the females injected with different hormones. Plasma cortisol and glucose levels increased significantly in males injected with CPE and females injected with hCG, but no significant change was observed in lactate levels before and after hormonal induction. Comparison of two sexes revealed significant differences in glucose levels for females in some groups before injection, while CPE-injected sexes showed significant changes in cortisol and lactate concentrations. The results indicated that the induction of ovulation or spermiation stimulated stress responses especially in female pikeperch, and therefore, all the procedures should be made to minimize the disturbance during the artificial spawning.

Relative effectiveness of carp pituitary extract, luteininzing hormone releasing hormone analog (LHRHa) injections and LHRHa implants for producing hybrid catfish fry

Adoption of the hybrid catfish (channel catfish, Ictalurus punctatus, female×blue catfish I. furcatus, male) is increasing in the catfish industry. The most effective way to produce fry is hormone induced spawning of females coupled with hand stripping and in vitro fertilization. The success of common carp pituitary extract (CPE), luteinizing hormone releasing hormone analog (LHRHa) injections and LHRHa implants for producing hybrid catfish fry was investigated over the past 15years. Data from 65 studies, 25, 20 and 20 for CPE, LHRHa injections, and LHRHa implants, respectively, were evaluated. Mean fry/kg female body weight (all females) produced was 948, 2483 and 2765 for CPE, LHRHa injections, and LHRHa implants, respectively. LHRHa administered as an injection or implant produced more (P<0.001)fry/kg than CPE. LHRHa implants and CPE (CV=37.5) gave a more consistent result (CV=35.9) than LHRHA injections (CV=49.9). LHRHa is advantageous for ovulating channel catfish for producing hybrid catfish fry compared to CPE. This advantage is even more important if brood fish, space or time are limiting.

Effect of timing of hormonal induction on reproductive activity in lambari (Astyanax bimaculatus)

The objective was to evaluate the influence of the timing of hormonal induction, using gonadorelin or common carp pituitary extract (CPE), on the reproductive activity of female Astyanax bimaculatus. Fish (N = 44) were weighed, measured, and acclimatized to experimental conditions with a photoperiod of 12 h:12 h light:dark (L:D) for 10 days. Ovulation was induced with a single dose of CPE (6 mg/kg) or gonadorelin (80 μg/kg), given at 12:00 (halfway through the light phase (LP) or 24:00 (halfway through the dark phase (DP), in a 2 × 2 factorial design. The time of ovulation was calculated in degree hours and daily motor activity was recorded using a photocell. The fish were killed and the liver and gonads were weighed for calculation of gonadosomatic (GSI) and hepatosomatic (HSI) indexes, respectively. Absolute fecundity (AF), absolute fecundity relative to weight (AFRW) and length (AFRL), diameter of oocytes (mM), and percentage of oocytes with the germinal vesicle in a peripheral position (PPGV) were recorded. All females responded (ovulated). The female Astyanax bimaculatus had twilight motor activity rhythm. Females given CPE at 12:00 had a higher (P < 0.05) percentage of oocytes with the germinal vesicle in a peripheral position compared with the group that received gonadorelin in the same period (95 ± 6 vs. 79 ± 21%, mean ± SD). The absolute fecundity relative to weight was higher in groups induced at 12:00, regardless of the hormone used (LP: 805 ± 448 and 700 ± 214, for CPE and gonadorelin, respectively; dark phase: 580 ± 396 and 529 ± 105, P < 0.05). Both times used for hormonal induction with CPE and gonadorelin were suitable for inducing reproduction in lambari, although induction with CPE in LP had the best results.

The Effect of Luteinizing Hormone Releasing Hormone Analog Regime and Stage of Oocyte Maturity for Induced Ovulation of Channel Catfish, Ictalurus punctatus

This study addresses rapid methods to identify mature channel catfish, Ictalurus punctatus, females for induced spawning with luteinizing hormone releasing hormone analog (LHRHa) and common carp pituitary extract (CPE) and the effects of stage of maturity, hormone dose, season, and cannulation before hormone injection. Hormonal intervention is the most effective method for inducing maturation and spawning in channel catfish × blue catfish, Ictalurus furcatus, hybrids. A total of 80 mature channel catfish were staged for maturity based on secondary sexual characteristics and 20–30 oocytes cannulated to ascertain their maturation stage based on the position of gonadal vesicle. Twenty females were randomly assigned to one of the four hormone regimes (priming + resolving dose): CPE 2 + 8 mg/kg (CPEC); LHRHa 20 + 40 µg/kg (LHRHaL); LHRHa 20 + 60 µg/kg (LHRHaM); and LHRHa 20 + 80 µg/kg (LHRHaH) and a fifth treatment consisted of 20 females selected based on apparent maturity as evidenced by external appearance were injected with CPE, 2 + 8 mg/kg without cannulation (CPEO). Two trials were conducted in early part of the spawning season and two trials in peak season. External methods to identify maturity correlated (r = 0.63) with that of “germinal vesicle position” method to identify the stage of maturity in females. Mean percent of females that ovulated, hatched, and fry produced per kg body weight did not differ (P > 0.05) among the five hormone treatments. The mean percent females that ovulated was higher (P 0.05) with that of non-cannulated catfish. The mean egg quality of hormone-induced females and percent of females ovulated in response to hormone treatment established a weak but significant linear relationship (Y = 3.85 + 0.008 × ovulation, r2 = 0.39, P < 0.05).

Semen characterization and sperm structure of the Amazon tambaqui Colossoma macropomum

Seminal features of tambaqui were evaluated after hormonal induction of spermiation with common carp pituitary extract. Seventeen adult (6.1 ± 0.9 kg, 62 ± 6 cm) males were collected from earthen ponds and transported to indoor concrete tanks. Semen was evaluated according to volume, pH, osmolality, motility, concentration, viability, sperm morphometry and morphological abnormalities. The semen of tambaqui was white and milky. The volume was 10.2 ± 5.1 mL at pH 8.0 ± 0.1, and yielded a concentration of 9.1 × 109 spermatozoa mL−1 while seminal plasma osmolality was 260 ± 7.3 mOsm kg−1. The percentage of viable sperm cells was determined with 97.0 ± 2.0% and 87.0 ± 8.0% using an eosin-nigrosin staining and fluorescent live-dead kit (propidium iodide and SYBR-14), respectively. A negative correlation (−0.65) between semen pH and sperm motility was observed suggesting this feature might influence the tambaqui sperm kinetics. Morphometrically the spermatozoa were on average 35.48 ± 1.55 μm long with a roundish head (mean length: 2.73 ± 0.21 μm; mean width: 2.58 ± 0.18 μm; n = 250 spermatozoa), without an acrosome, and presented a long midpiece (2.90 ± 0.52 μm) and flagellum (29.84 ± 1.63 μm). About 15.8% of the spermatozoa carried morphological abnormalities, with bent tail being the most frequent defect (7.81 ± 3.12%). The characterization of tambaqui semen favors the development of more precise and efficient procedures for its analysis and utilization in controlled breeding.

Use of Prussian carp, &lt;I&gt;Carassius gibelio,&lt;/I&gt; pituitaries in the artificial propagation of female common carp, &lt;I&gt;Cyprinus carpio&lt;/I&gt;

Background. The usage of common carp pituitaries has been associated with very high costs, resulting from sac rificing the valuable broodstock. A close taxonomic proximity between the Common carp, Cyprinus carpio L., and Prussian carp, Carassius gibelio (Bloch, 1782), reflected in the presence of high levels of the homologous carp LH hormone in Prussian carp pituitaries, was recently demonstrated. This prompted the present authors to evaluate the Prussian carp pituitaries as a less expensive alternative to carp pituitaries, for inducing spawning in common carp. Materials and Methods. Prussian carp were fished in Lake Pamvotis (NW Greece) on April 4, 2007 and 204 pituitaries were extracted and processed. Accordingly, the prepared pituitary liquid extract was injected in 30 female common carp (experimental group) in the State Carp Hatchery in Psathotopi, (western Greece). Common carp pituitary extract was used for the hypophysation of female common carp in the control group ( n = 30). In both groups, standard hatchery procedures were followed concerning broodstock handling during the artificial propagation of common carp. Fertilized eggs were incubated in 7-L Zugar jars after removing the sticky substrate and hatching percentage was calculated. Results. Spawning success was 73.3%, total egg yield was 5.94 kg, total relative fecundity was 112.5 g · kg –1 of body weight (150.0 g · kg –1 of body weight based on fertile broodstock), and hatching percentage reached 85.2 %. Statistically, all the above performance values were not significantly different compared to the controls. Conclusion. Taking advantage of a natural resource practically unexploited, the use of Prussian carp pituitaries in the artificial propagation of common carp was equally effective to common carp pituitaries, contributing to lower running costs in the hatchery.

Early development of the silver catfishRhamdia quelen(Quoy &amp; Gaimard, 1824) (Pisces:Heptapteridae) from the São Francisco River Basin, Brazil

The silver cat¢sh, Rhamdia quelen, is endemic to North, Central and South America with high aquaculture potential and wide acceptance in the market. Breeder ¢sh were subjected to induced reproduction through hypophysation using a crude common carp pituitary extract. Egg characteristics, oocyte surface ultrastructure and histology of larval ontogenesis until whole yolk resorption were described for the ¢rst time for this species. Oocytes and semen were obtained by manual extrusion, and fertilization was conducted using the dry method. After fertilization, eggs were kept in incubators at 241C. The embryonic development was monitored using a stereomicroscope every 10 min until hatching. To analyse the larval development, larvae samples were collected from incubators daily until the ¢fth day, ¢xed in Bouin’s £uid and subjected to routine histological techniques. The oocyte extrusion occurred 8 h after the second hormone dose at 261C. The oocytes were spherical, non-adhesive and yellow, with a diameter of 1471.75 � 47.63 mm. Scanning electron microscopy revealed a thin jelly coat covering the zona radiata in the animal pole around the micropyle. The blastopore closure occurred within 8 h after fertilization, and the fertilization rate was 79.9 � 5.2% at 24 1C. Embryonic development was completed within 25 h 30 min after fertilization. The complete resorption of the yolk and the formation of the digestive system organs and the mouth opening occurred on the ¢fth day, indicating a need for exogenous feeding. The results of this study provide information important for improvement in R. quelen culture and management.

Changes along the pituitary-gonadal axis during maturation of the black carp,Mylopharyngodon piceus

The black carp, Mylopharyngodon piceus, is a late-maturing cyprinid reaching sexual maturity at the age of 6-7 years. The present work attempted to define nonfunctional sites along the pituitary-gonadal axis in immature fish utilizing in vivo and in vitro challenge experiments. Two- and 3-year old fish injected with salmon gonadotropin-releasing hormone analog (sGnRHa; 10 microg/kg) and metoclopramide (20 mg/kg) did not reveal any increase in circulating gonadotropin (cGtH) or estradiol (E(2)) level. Furthermore, cGtH release from cultured pituitary cells of fish at these ages did not increase in response to sGnRH (0.1 nM - 1 microM) but was augmented when exposed to TPA (12.5 nM). However, 4-year old female fish did respond to the above treatments both in vivo and in vitro. These results suggest the existence of nonfunctional site(s) proximal to the activation of PKC in the immature black carp gonadotrophs, probably at the level of GnRH receptors. These site(s) start to become functional in 4-year old fish. Two- and 3-year old fish injected with common carp pituitary extract (CPE) containing 350 microg cGtH/kg did not show any increase in circulating E(2). In addition, the estrogen secretion from fragments of the rudimentary gonads did not increase after exposure to CPE containing cGtH (0.5-4 microg/ml) but was elevated dose-dependently by exposure to dbcAMP (0.3-3 mM). However, the ovaries of 4-year old fish did respond to the gonadotropic stimulation, both in vivo and in vitro. These results suggest the existence of other non-functional site(s) in the immature black carp, proximal to the formation of cAMP in the gonads, probably at the level of GtH receptors. These site(s) start to become functional in 4-year old females. Another source of E(2) was discovered in the immature black carp: namely, the fat pad adjacent to the gonads. In contrast to the visceral adipose tissue, the fat pad secretes estrogen in response to cAMP elevation in 2- and 3-year old fish while in 4-year old fish it also responds to gonadotropic stimulation. Due to its large mass and high steroidogenic potency, it is assumed that the gonadal fat pad is involved in the process of puberty in the black carp. J. Exp. Zool. 286:405-413, 2000.

Induced spawning techniques practised at Batu Berendam, Melaka, Malaysia

Techniques of induced spawning as practised at Batu Berendam, Melaka, were developed from 1974 to 1986. Early attempts using salmon gonadotropin SG-G100 were found to be effective but very expensive. Alternatively, the technique of hypophysation, that is, injection of either homoplastic or heteroplastic pituitary gland extract, was adopted. Freshly prepared or acetone-pre-served pituitary extracts from mature bighead and silver carp were administered to bighead and silver carp spawners; the extracts were found to be effective and 30 times cheaper than SG-G100. In addition, the use of acetone-dried common carp pituitary extract produced more consistent results. Using this technique, we were able to induce spawning in local as well as exotic carps. More refined human chorionic gonadotropin administered with homoplastic or heteroplastic pituitary extract proved to be equally effective on local as well as exotic carps and catfish. Some of the dosages have been standardized, in particular for bighead carp, Aristichthys nobilis, silver carp, Hypophthalmichthys molitrix, local carp, Leptobarbus hoevenii, and striped catfish, Pangasius sutchi. The most recent development is the effective administration of luteinizing hormone-releasing hormone analog to P. sutchi, either singly or in combination with homoplastic pituitary extract.