904 resultados para Somatolactin hormone
Resumo:
Based on the recovery rates for Thalassia testudinum measured in this study for scars of these excavation depths and assuming a linear recovery horizon, we estimate that it would take ~ 6.9 years (95% CI. = 5.4 to 9.6 years) for T. testudinum to return to the same density as recorded for the adjacent undisturbed population. The application of water soluble fertilizers and plant growth hormones by mechanical injection into the sediments adjacent to ten propellor scars at Lignumvitae State Botanical Site did not significantly increase the recovery rate of Thalassia testudinum or Halodule wrightii. An alternative method of fertilization and restoration of propellor scars was also tested by a using a method of “compressed succession” where Halodule wrightii is substituted for T. testudinum in the initial stages of restoration. Bird roosting stakes were placed among H.wrightii bare root plantings in prop scars to facilitate the defecation of nitrogen and phosphorus enriched feces. In contrast to the fertilizer injection method, the bird stakes produced extremely high recovery rates of transplanted H. wrightii. We conclude that use of a fertilizer/hormone injection machine in the manner described here is not a feasible means of enhancing T. testudinum recovery in propellor scars on soft bottom carbonate sediments. Existing techniques such as the bird stake approach provide a reliable, and inexpensive alternative method that should be considered for application to restoration of seagrasses in these environments. Document contains 40 pages)
Resumo:
89 ripe female brooders of the catfish, Clarias anguillaris (Body wt. Range 150g-1, 200g) were induced to spawn by hormone (Ovaprim) induced natural spawning technique over a period of 10 weeks. Matching ripe males were used for pairing the females at the ratio of two males to a female. Six ranges of brood stock body weights were considered as follows; <200g; 200g-399g; 400g-599g; 600-799g; 800g-999g; > 1000g and the number of fry produced by each female brooder was scored/recorded against the corresponding body weight range. The number of fry per unit quantity of hormone and the cost of production a fry based on the current price of Ovaprim (hormon) were determined so as to ascertain most economic size range. The best and most economic size range was between 400g-599g body weight with about 20,000 fry per ml of hormone and N0.028 per fry, while the females above 1000g gave the poorest results of 9,519 fry per ml of hormone and N0.059 per fry. For optimum production of Clarias anguillaris fry and maximum return on investment female brooders of body weights ranging between 400g-599g are recommended for hormone induced natural breeding exercises
Resumo:
89 ripe female brooders of the catfish, Clarias anguillaris (Body wt. Range 150g-1, 200g) were induced to spawn by hormone (Ovaprim) induced natural spawning technique over a period of 10 weeks. Matching ripe males were used for pairing the females at the ratio of two males to a female. Six ranges of brood stock body weights were considered as follows; <200g; 200g-399g; 400g-599g; 600-799g; 800g-999g; > 1000g and the number of fry produced by each female brooder was scored/recorded against the corresponding body weight range. The number of fry per unit quantity of hormone and the cost of production a fry based on the current price of Ovaprim (hormon) were determined so as to ascertain most economic size range. The best and most economic size range was between 400g-599g body weight with about 20,000 fry per ml of hormone and N0.028 per fry, while the females above 1000g gave the poorest results of 9,519 fry per ml of hormone and N0.059 per fry. For optimum production of Clarias anguillaris fry and maximum return on investment female brooders of body weights ranging between 400g-599g are recommended for hormone induced natural breeding exercises
Resumo:
This investigation has resulted in the chemical identification and isolation of the egg-laying hormone from Aplysia californica, Aplysia vaccaria, and Aplysia dactylomela. The hormone, which was originally identified as the Bag Cell-Specific protein (BCS protein) on polyacrylamide gels, is a polypeptide of molecular weight ≈ 6000, which is localized in the neurosecretory bag cells of the parietovisceral ganglion and the surrounding connective tissue sheath which contains the bag cell axons. All three species produce a hormone of similar molecular weight, but varying electrophoretic mobility as determined on polyacrylamide gels. As tested, the hormone is completely cross-reactive among the three species.
Although the bag cells of sexually immature animals contain the active hormone, sexual maturation of the animal results in a 10-fold increase in the BCS protein content of these neurons.
A seasonal variation in the BCS protein content was also observed, with 150 times more hormone contained in the bag cells of Aplysia californica in August than in January. This correlates well with the variation in the animals' ability to lay eggs throughout the year (Strumwasser et al., 1969). There are some indications that the receptivity of the animal to the available hormone also fluctuates during the year, being lower in winter than in swmner. The seasonal rhythm of the other species, Aplysia vaccaria and Aplysia dactylomela, has not been investigated.
A polyacrylamide gel electrophoresis analysis of water-soluble proteins in Aplysia californica revealed several other nerve-specific proteins. One of these is also located in the bag cell somas and stains turquoise with Amido Schwarz. The function of this protein has not been investigated.
Resumo:
Two hormone preparations viz. Human Chorionic Gonadotropin (HCG) and pituitary gland (PG) suspension were compared for their comparative efficacy on the breeding performance of a air breathing catfish Clarias batrachus. It was found that HCG induced fish gave better ovulation response than PG. Both fertilization and hatching of eggs were significantly (p
Resumo:
Effects of age and season on the developmental capacity of oocytes from unstimulated and FSH-stimulated rhesus monkeys were examined, Immature cumulus-oocyte complexes were matured in vitro in modified CMRL-1066 medium containing 20% bovine calf serum and
Resumo:
The growth hormone (GH) gene family represents an erratic and complex evolutionary pattern, involving many evolutionary events, such as multiple gene duplications, positive selection, the birth-and-death process and gene conversions. In the present study, we cloned and sequenced GH-like genes from three species of New World monkeys (NWM). Phylogenetic analysis strongly suggest monophyly for NWM GH-like genes with respect to those of Old World monkeys (OWM) and hominoids, indicating that independent gene duplications have occurred in NWM GH-like genes. There are three main clusters of genes in putatively functional NWM GH-like genes, according to our gene tree. Comparison of the ratios of nonsynonymous and synonymous substitutions revealed that these three clusters of genes evolved under different kinds of selective pressures. Detailed analysis of the evolution of pseudogenes showed that the evolutionary pattern of this gene family in platyrrhines is in agreement with the so-called birth-and-death process.
Resumo:
Pituitary growth hormone (GH) evolves very slowly in most of mammals, but the evolutionary rates appear to have increased markedly on two occasions during the evolution of primates and ruminants. To investigate the evolutionary pattern of growth hormone receptor (GHR), we sequenced the extracellular domain of GHR genes from four primate species. Our results suggested that GHR in mammal also shows an episodic evolutionary pattern, which is consistent with that observed in pituitary growth hormone. Further analysis suggested that this pattern of rapid evolution observed in primates and ruminants is likely the result of coevolution between pituitary growth hormone and its receptor.
Resumo:
Growth hormone is a classic molecule in the study of the molecular clock hypothesis as it exhibits a relatively constant rate of evolution in most mammalian orders except primates and artiodactyls, where dramatically enhanced rate of evolution (25-50-fold) has been reported. The rapid evolution of primate growth hormone occurred after the divergence of tarsiers and simians, but before the separation of old world monkeys (OWM) from new world monkeys (NWM). Interestingly, this event of rapid sequence evolution coincided with multiple duplications of the growth hormone gene, suggesting gene duplication as a possible cause of the accelerated sequence evolution. Here we determined 21 different GH-like sequences from four species of OWM and hominoids. Combining with published sequences from OWM and hominoids, our analysis demonstrates that multiple gene duplications and several gene conversion events both occurred in the evolutionary history of this gene family in OWM/hominoids. The episode of recent duplications of CSH-like genes in gibbon is accompanied with rapid sequence evolution likely resulting from relaxation of purifying selection. GHN genes in both hominoids and OWM are under strong purifying selection. In contrast, CSH genes in both lineages are probably not. GHV genes in OWM and hominoids evolved at different evolutionary rates and underwent different selective constraints. Our results disclosed the complex history of the primate growth hormone gene family and raised intriguing questions on the consequences of these evolutionary events. © 2005 Elsevier B.V. All rights reserved.
Resumo:
A study was conducted to determine the effects of single injections of human chorionic gonadotropin (HCG) and Durandron Forte 250 on sperm motility, vitality and density and also on the consistency of milt in newly caught, wild, mature milkfish (Chanos chanos). In contrast to HCG, single injections of Durandron Forte 250 were effective not only in inducing spermiation but also in maintaining newly caught mature males in good running condition for a maximum of 7 days, despite daily handling and collection of approximately 3ml milt.
Resumo:
This paper describes the optimization of dose of methyltestosteronei (MT) hormone for masculinization of tilapia (Oreochromis niloticus). Five treatments (i.e. T1 T2, T2, T4 and T5) with different doses such as 0, 40, 50, 60 and 65 mg of MT hormone were mixed with per kg of feed for each treatment and fed the fry four times a day up to satiation for a period of 30 days. The stocking density was maintained 10 spawn/liter of water. The growth of fry at different treatments was recorded weekly and mortality was recorded daily. At the end of hormone feeding the fry were reared in hapas fixed in ponds for another 70 days and at the 100th day the fish were sexed by the gonad squashing and aceto-carmine staining method. The analysis of growth data did not show any significant variation in length and weight of fish among the different treatments. High mortality of fry ranging 66% to 81.6% was observed in different treatments and highest mortality was observed during the first twelve days of the experiment. The sex ratio analysis showed that T2 (40 mg/kg) and T5 (65 mg/kg) produced 93.33% of sex reversed male and T3 (50 mg/kg) and T4 (60 mg/kg) produced 96.66% sex reversed male, and these ratios were significantly (p<0.05) different from 1:1 male: female sex ratio. The control, T1 (0 mg/kg) contained 43.33% male progeny. From these results it is suggested that either 50 mg/kg or 60 mg/kg of MT with a feeding period of 30 days could be considered as an optimum dose for masculinization of tilapia (O. niloticus).
Resumo:
An attempt was made to breed goldspot mullet, Liza parsia in captivity through hormone induction. The fish started spawning 35-36 hours after a single dose of 2ml ova prim per kg body weight. Hatching of fertilized eggs completed within 42-48 hours after spawning. The mean hatching rate (%) was 71.33±12 corresponding to the fertilization rate (%) of 64±12. The larvae started its first external feeding on the third day and attained a length 2.5±0.25 mm. The salinity of both breeding and rearing cisterns was 20‰ and temperature was maintained at 22-23°C.