83 resultados para nitrogenous fertilization
em Aquatic Commons
Resumo:
ENGLISH: The anchoveta, Cetengraulis mysticetus (Günther), is an important bait fish used to capture tunas in the Eastern Tropical Pacific Ocean. Contributions to the early life history of this species in the Gulf of Panama were made by Simpson (1959), who was able to identify deductively the planktonic egg of the anchoveta from 10 other anchovy eggs concurrently present. He also reared these planktonic eggs in the laboratory and described the resultant larvae to the age of 48 hours after hatching. Because of the lack of differences among the anchovy larvae, this description does not permit the identification of anchoveta larvae from those of other engraulid species. Furthermore, while adult specimens are easily recognized, up to the present it has not been possible to extend the identification of the juvenile anchoveta to specimens smaller than about 25 mm. The purpose of this study, therefore, was to identify anchoveta from the time of hatching to about 25 mm. SPANISH: La anchoveta, Cetengraulis mysticetus (Günther), es un importante pez de carnada que se emplea en la captura de los atunes en el Océano Pacífico Oriental Tropical. Simpson (1959) logró identificar deductivamente el huevo planctónico de la anchoveta al separarlo de otros diez huevos de anchoas que se encuentran al mismo tiempo, contribuyendo de esta manera a conocer los primeros estados de la historia natural de esta especie en el Golfo de Panamá. El también estableció un criadero en el laboratorio con estos huevos planctónicos y describió las larvas resultantes hasta la edad de 48 horas después de la eclosión. Debido a que no hay diferencias entre las larvas de las anchoas, esta descripción no permite identificar las larvas de la anchoveta de las otras especies de engráulidos. Más aun, a pesar de que los especímenes adultos son fácilmente reconocibles, hasta ahora no ha sido posible identificar la anchoveta juvenil de menos de unos 25 mm. Consecuentemente, el propósito del presente estudio ha sido el de identificar al anchoveta desde el momento de la eclosión hasta que tiene unos 25 mm.
Resumo:
The success of induced spawning for the production of fish seed depends on many factors which affect hatchery conditions. This paper discusses the results of an investigation on the effects of six different levels of salinity on the fertilization and hatching of Heterobranchus bidorsalis eggs. The results indicate that spermatozoa of H. bidorsalis can survive under a wide range of saline concentrations, with survival increasing with an increase in salinity from 0 to 0.4% and then decreasing as the level of salinity increases. Survival was optimum of 0.4% saline concentration.
Resumo:
A study on mixed culture of mirror carp (Cyprinus carpio Lin.), tilapia (Oreochromis niloticus Lin.), silver carp (Hypophthalmicthys molitrix Val.) and Thai sharpunti (Puntius gonionotus Bleeker) in the ratio of 1:2:2:5 was conducted in 12 seasonal mini ponds (30 m² each) for 105 days. There were six treatments each with two replicates and each pond was stocked with a total of 100 fishes. Rice bran and mustard oil cake were used as supplemental feed either in combination or alone in presence or absence of fertilizer. Fertilizers were used in the form of organic, inorganic or both. The best growth performance of mirror carp, tilapia and Thai sharpunti was obtained in treatment III which received both fertilizer (organic+inorganic) and rice bran while the highest growth of silver carp was obtained in treatment VI receiving only inorganic fertilizer. However, the overall best production (2450 Kg/ha) and economic return for the culture period was obtained in treatment VI followed by treatment III. The results are discussed in the light of water quality parameters.
Resumo:
A 120-day long experiment was conducted to find out the effects of urea plus triple super
phosphate (UT), cow manure (CM) and poultry manure (PM) having iso-nil:rogen
content on pond productivity and fish yield. Three fertilizer treatments, with three
replicates each, were randomly assigned into nine earthen ponds of 100 m2 each. The
stocking fish were rohu (Labeo ruhita), catla ( Catla catla) and mrigal ( Cirrhinus
mrigala) in each treatment pond at the rate of 10000/ha with the ratio of 1:1:1. All ponds
were fertilized fortnightly at the rate of 125 kg/ha urea plus 100 kg TSP/ha, 7000 kg/ha
cow manure and 3500 kg/ha poultry manure for the treatment of UT, CM and PM,
respectively, having an iso-nitrogen content of 56 kg in each. Though the physicochemical
water quality parameters were more or less similar in all treatment ponds, the
chlorophyll-a content and abundance of total plankton were significantly higher (P <
0.05) in the ponds receiving the treatment PM. Final growth as well as per unit
production of fish was significantly higher (p
Resumo:
A 120 day long experiment was conducted to find out the effects of cow manure with urea and triple super phosphate (CUT), poultry manure with urea and triple super phosphate (PUT) and cow manure with poultry manure (CP) having similar quantities of nitrogen and phosphorus on pond productivity and fish yield. The stocking fish were rohu (Labeo rohita), catla ( Catla catla) and mrigal ( Cirrhinus mrigala) in each treatment pond at the rate of 10000/ha. All ponds were fertilized fortnightly at the rate of 4000 kg/ha cow manure with 62 kg/ha urea and 65 kg/ha TSP, 2700 kg/ha poultry manure with 62 kg/ha urea and 16 kg/ha TSP, and 4000kg/ha cow manure with 2700 kg/ha poultry manure for the treatment CUT, PUT and CP respectively. Each treatment contained an iso-nitrogen and iso-phosphorus of 56 kg and 46 kg respectively. Though the physico-chemical parameters were more or less similar in all ponds, the chlorophyll-a content and abundance of total plankton were significantly higher (P< 0.05) in the ponds receiving the fertilizer treatment of PUT than those of other treatments. Final growth as well as per unit production of fish of treatment PUT (1773 kg/ha) was significantly higher (P< 0.05) than that of treatment CP (1528 kg/ha) followed by that of treatment CUT (1336 kg/ha). The over all results showed that poultry manure with urea and triple super phosphate proved to be superior to cow manure with urea and triple super phosphate, and poultry manure with cow manure, even when nitrogen and phosphorus content was similar, in carp polyculture system under prevailing conditions.
Resumo:
A water soluble hygroscopic powder has been isolated from squilla in good yield, ranging from 3.5 to 5.0% of the fresh raw material, by a simple direct method. The process consists of homogenising squilla with an equal quantity of water, removal of chitinous matter from the slurry by filtration, heating the filtrate at 0.7 kg/sq.cm steam pressure for 15-20 minutes, removal of the precipitated protein by filtration and concentration and final drying in vacuum of the filtered cooled liquor. The pale brown powder so obtained consists mainly of peptones and proteoses and has been found to be comparable to BDH peptone for growth of bacteria, ability to serve as source for tryptophan for indole production and to provide substrate for the production of hydrogen sulphide. Comparative studies have been made on similar water soluble fractions from two species of prawns, namely, Metapenaeus affinis and Parapenaeopsis stylifera.
Resumo:
Oil sardines in prime condition were subjected to onboard chilling. Two lots were chilled in CSW (samples C and CI), a third lot was chilled in crushed ice (sample I) and a fourth lot left not iced on deck (Sample AI). Upon landing sample AI was iced and sample CI was removed from the CSW and iced. All the four samples were kept in a chilled room for storage studies. The fish chilled and stored in CSW recorded the least, and the fish subjected to delayed icing, the highest values for all the indices of spoilage namely, free amino nitrogen, trimethylamine (TMA) and total volatile base nitrogen (TVBN). The total psychrophilic bacterial number also showed a similar trend. The organoleptic assessment of the cooked samples revealed C I, CI, AI to be the order of preference throughout the storage. This assessment was found to hold good for the rest of the parameters as well. The CSW held fishes were found to be distinctly superior to the iced ones for the first five days of storage. Such a marked prevalence in quality for five days would suffice for the fish to fetch a premium in the market over other landings of the same fish whether chilled or not chilled. Chilling on board in CSW and icing the same after landings, did not show encouraging results.
Resumo:
The results are presented of attempts to artificially fertilize Mugil cephalus eggs in the Philippines. Embryonic development is outlined and rearing of the larvae described. Mass mortality occurred during week 3 of rearing.
Resumo:
Brood catfish, Heteropneustes fossilis were collected from Tamirabarani river basin of Tamil Nadu, India and kept in cement tanks. Three inducing hormones viz, Ovaprim, Ovatide and WOVA-FH were injected at the rate of 0.5, 1.0, 1.5 and 2.0 ml/kg body weight in order to induce oocyte maturation and ovulation. After 10-13h of injection at a water temperature of 27±-0.5°C, stripping of eggs and in vitro fertilization was done. Ovaprim gave maximum (94.67%) hatching rate followed by Ovatide (90.33%) and WOVA-FH (77.33%).
Resumo:
During a two years research hydrogen peroxide efficacy evaluated for Persian sturgeon, Chinese carps and common carp eggs. These series of the experiments conducted in various conditions different concentration of hydrogen peroxide include 250, 500, 750, 1,000 1,500 2,000 3,000 and 9,000 PPM used as ten and fifteen minutes baths, compared with Malachite green and natural control . In the next phase effect of Levaemisole hydrochloride as an immunostimulator which applied as 5 mg/I in twenty minutes baths from day sixth after hatch evaluated by daily mortality rate and leukocytes counts. The results shown that according fertilization percent and temperature condition hydrogen peroxide at 1,000 and 1,500 PPM concentrations is a effective antifungal agent during incubation periods of Persian sturgeon and even sometimes increasing hatching rates significantly comparing with natural controls and Malachite green. In Chinese carps although hydrogen peroxide controls water molds but it is not recommended in high temperatures because it make shortened incubation time and mold infections will decrease. Also the results shown 750 PPM concentration of hydrogen peroxide in common carp eggs controls water moulds infections and increase hatching rate significantly comparing with Malachite green and natural control. Daily mortality rates accessing of Persian sturgeon fries show that 20 minutes baths of 5mg/1 levamisole hydrochloride decreases daily mortality rate during yolk sac absorption. Nitrogenous compounds: nitrate and ammonium differ significantly between treated tanks with control. Blood leucocytes concentrations as an immune index was different significantly in treated fishes by levamisole hydrochloride comparing with controls. In Chinese carps because yolks sac absorption time is short there is not necessary to use the levamisole hydrochloride. Although treated larvae were more active than controls. As a result our suggestions is to use hydrogen peroxide in Persian sturgeon and common carp artificial propagation and also suggest the use levamisole hydrochloride for Persian sturgeon beside management method in stress and pollution condition
Resumo:
Report of Opening Session (pdf 0.07 Mb) Report of Governing Council (pdf 0.2 Mb) Report of the Finance and Administration Committee (pdf 0.07 Mb) Reports of Science Board and Committees Science Board inter-sessional meeting (pdf 0.07 Mb) Science Board (pdf 0.1 Mb) Biological Oceanography Committee (pdf 0.2 Mb) Fishery Science Committee (pdf 0.04 Mb) Marine Environmental Quality Committee (pdf 0.06 Mb) MONITOR Technical Committee (pdf 0.05 Mb) Physical Oceanography and Climate Committee (pdf 0.06 Mb) Technical Committee on Data Exchange (pdf 0.04 Mb) Reports of Sections, Working and Study Groups Section on Ecology of harmful algal blooms in the North Pacific (pdf 0.03 Mb) Section on Carbon and Climate Working Group 18 on Mariculture in the 21st century - The intersection between ecology, socio-economics and production (pdf 0.06 Mb) Working Group 19 on Ecosystem-based management science and its application to the North Pacific (pdf 0.03 Mb) Reports of the Climate Change and Carrying Capacity Program Implementation Panel on the CCCC Program (pdf 0.04 Mb) CFAME Task Team (pdf 0.04 Mb) MODEL Task Team (pdf 0.04 Mb) Reports of Advisory Panels Advisory Panel on Iron Fertilization Experiment in the Subarctic Pacific Ocean (pdf 0.04 Mb) Advisory Panel on Marine Birds and Mammals (pdf 0.03 Mb) Advisory Panel on Micronekton Sampling Inter-Calibration experiment (pdf 0.05 Mb) Summary of Scientific Sessions and Workshops (pdf 0.2 Mb) Membership List (pdf 0.07 Mb) List of Participants (pdf 0.07 Mb) List of Acronyms (pdf 0.03 Mb)
Resumo:
Report of Opening Session (pdf 0.07 Mb) Report of Governing Council (pdf 0.2 Mb) Report of the Finance and Administration Committee (pdf 0.08 Mb) Reports of Science Board and Committees Science Board inter-sessional meeting (pdf 0.05 Mb) Science Board (pdf 0.1 Mb) Biological Oceanography Committee (pdf 0.1 Mb) Fishery Science Committee (pdf 0.04 Mb) Marine Environmental Quality Committee (pdf 0.04 Mb) Physical Oceanography and Climate Committee (pdf 0.04 Mb) Technical Committee on Data Exchange (pdf 0.04 Mb) Reports of Sections, Working and Study Groups Harmful Algal Blooms Section (pdf 0.03 Mb) Working Group 17 on Biogeochemical data integration and synthesis (pdf 0.03 Mb) Working Group 18 on Mariculture in the 21st century - The intersection between ecology, socio-economics and production (pdf 0.06 Mb) Study Group on Ecosystem-based management science and its application to the North Pacific (pdf 0.04 Mb) Reports of the Climate Change and Carrying Capacity Program Implementation Panel on the CCCC Program (pdf 0.04 Mb) BASS Task Team (pdf 0.04 Mb) CFAME Task Team (pdf 0.04 Mb) MODEL Task Team (pdf 0.04 Mb) MONITOR Task Team (pdf 0.03 Mb) REX Task Team (pdf 0.04 Mb) Reports of Advisory Panels Advisory Panel on Continuous Plankton Recorder Survey in the North Pacific (pdf 0.4 Mb) Advisory Panel on Iron Fertilization Experiment in the Subarctic Pacific Ocean (pdf 0.03 Mb) Advisory Panel on Marine Birds and Mammals (pdf 0.04 Mb) Advisory Panel on Micronekton Sampling Inter-Calibration experiment (pdf 0.04 Mb) Summary of Scientific Sessions and Workshops (pdf 0.2 Mb) Membership List (pdf 0.07 Mb) List of Participants (pdf 0.09 Mb) List of Acronyms (pdf 0.03 Mb)