Now showing items 2183-2202 of 3378

    • Article

      Observation on the host-parasite relationship of Epipenaeon ingens Nobili (Epicaridea: Bopyridae) and Penaeus semisulcatus De Haan. 

      FJ Palisoc - Philippine Journal of Science, 1987 - Science and Technology Information Institute
      Sample of Penaus semisulcatus or Tiger Shrimp ("hipong bulik") from Manila Bay and Tayabas bay, and from waters off Palawan, Cebu, Samar and Capiz were obtained from Navotas Fishery Port during the period from March, 1978 to Febuary, 1979. The prevalence of Epipenaeon ingens in P. semisulcatus is 4.83/1000. No significant difference (P>0.05) in the prevelence of infection between the sezes was found. The parasites (E. ingens) was lodged on either side of the host's carapace and there was no significant difference in the regression analyses of the tumor size on carapace length wheter tumor is on the left or right side of the carapace of either male or female host. Despite the homogenity of regression lines in the comparative analyses of length-weight relationship of infected and uninfected P. semisulcatus, the slope of the regression of the infected sample are always higher than the value for the uninfected ones.
    • Article

      Observations on artificial fertilization of eggs and embryonic and larval development of milkfish, Chanos chanos (Forskal) 

      H Chaudhuri, JV Juario, JH Primavera, R Samson & R Mateo - Aquaculture, 1978 - Elsevier
      Hydrated eggs obtained from a female milkfish, Chanos chanos, were artificially fertilized with the milt collected from a male injected with acetone-dried pituitaries of salmon. The fertilized eggs (1.1–1.25 mm in diameter) developed normally in seawater in basins and petri dishes at a salinity of 30–34‰, and successfully hatched in 25–28.5 hours at a temperature of 26.4–29.9°C. The yolk was completely absorbed in about 2.5 days and during this period many postlarvae died. A few larvae were reared up to 5 days but all died on the 6th day. Attempts were made to feed the postlarvae with freshly hatched trochophore larvae of oysters obtained from eggs artificially fertilized in the laboratory.
    • Article

      Observations on the artificial fertilization of eggs and larval rearing of the grey mullet, Mugil cephalus L. 

      JV Juario, M Natividad, V Duray, J Nacario, J Almendras & J Canto Jr. - SEAFDEC Aquaculture Department Quarterly Research Report, 1978 - Aquaculture Department, Southeast Asian Fisheries Development Center
      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.
    • Oral presentation

      Observations on the nauplii production from wild, cultivated and mixed populations of the blue shrimp (Penaeus stylirostris) 

      RA Mendoza - In Y Taki, JH Primavera & JA Llobrera (Eds.), Proceedings of the First International Conference on the Culture of Penaeid Prawns/Shrimps, 4-7 December 1984, Iloilo City, Philippines, 1985 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Due to low nauplii production from cultivated broodstock and to minimize dependence on wild stock, an experiment was run in which four treatments, consisting of combinations of 400 adult blue shrimp (Penaeus stylirostris) from wild and cultivated (F6) populations, were applied (wild females and males, wild females and cultivated males, cultivated females and wild males, and cultivated females and males). Females were inspected every third day. Those observed with spermatophores were captured and transferred to individual 100-ℓ spawning tanks. Water was treated with EDTA and erythromycin phosphate. More than 300 individual spawns were evaluated within a 180-day period. To evaluate the nauplii production per female, an analysis of variance for a factorial arrangement (43 × 2) was conducted. The factors considered were: the abovementioned treatments, different ovarian maturation stages, adhesion of the spermatophore, and kind of spawning (complete or partial). The mixed populations had higher nauplii production than the cultivated broodstock. All the females were tagged around an eyestalk and examined for rematuration. Up to six rematurations per female were registered as well as a minimum of four days between successive spawnings for the same female. The effect of rematuration on the quantity of nauplii is discussed. Gonadosomatic index for wild and cultivated females is compared. Selective criteria for spawners are given.
    • Article

      Occurrence and distribution of milkfish larvae, Chanos chanos off the western coast of Panay Island, Philippines 

      T Bagarinao & S Kumagai - Environmental Biology of Fishes, 1987 - Springer Verlag
      The occurence and distribution of milkfish larvae (∼3–17 mm TL) off western Panay Island, Philippines are reported based on 594 plankton net tows made in April and May 1980. Forty-two tows yielded 44 larvae, together with 1149 milkfish eggs by 98 tows. About 70% of the larvae of all stages came from stations less than 100 m deep and 1–2 km from land. Younger larvae up to 6 mm and about 1 week old occurred at stations of various distances from shore, while older larvae occurred only near shore. About 48% of larvae of all stages were caught by surface tows; younger larvae occurred also in deeper layers (20 and 30 m). Larval abundance increased towards May. Younger larvae tended to occur during the quarter moon periods and older ones during the full and new moon periods.
    • Article

      Occurrence and histopathogenesis of a didymozoid trematode (Gonapodasmius epinepheli) in pond-reared orange-spotted grouper, Epinephelus coioides 

      ER Cruz-Lacierda, RJG Lester, PS Eusebio, HS Marcial & SAG Pedrajas - Aquaculture, 2001 - Elsevier
      A didymozoid trematode encapsulated in the gills of orange-spotted grouper, Epinephelus coioides Hamilton, was observed in October 1997 and September 1999 among pond-reared fish in the Philippines. Capsule prevalence was 33% and 18% and mean intensity 2 and 1, respectively. The opaque-white and yellowish capsules were found only on the first gill arch and were attached lengthwise along the posterior surface of the primary gill filaments. When the capsules were opened, long thread-like worms were revealed, which were identified as Gonapodasmius epinepheli Abdul-Salam, Sreelatha and Farah. The parasites were encapsulated between the basement membrane of the epithelium and the efferent artery of the gill filament. The response of the host included mild hyperplasia of the interlamellar epithelium and an increase in the number of mucous cells.
    • Article

      Occurrence and pathology of an Amyloodinium-like protozoan parasite on gills of grey mullet, Mugil cephalus 

      MCL Baticados & GF Quinitio - Helgolander Meeresuntersuchungen, 1984 - Biologische Anstalt Helgoland
      In cultured grey mullets, Mugil cephalus L., mortalities caused by a dinoflagellate-like parasite were observed under normal rearing conditions. Moribund fish were abnormally swimming near the water surface and exhibited haemorrhagic areas on the head, around the mouth and on the body surfaces. Their gills displayed whitish spots as well as haemorrhagic areas and showed excessive mucus production. Microscopic examination of these whitish spots revealed structures highly resembling the trophonts of Amyloodinium attached to the gill filaments. The most consistent feature of this parasitic infestation was lamellar disintegration or degeneration. Early stages of the infestation showed epithelial lifting and lamellar detachment, eventually leading to the disruption of the lamellae and lamellar tissue degeneration. The parasites were associated with large necrotic areas in the gills and caused degeneration of the gill ray tissues. Hyperplasia of the gill epithelium and lamellar fusion were also observed, with the parasites enclosed by the fused lamellae. These structural alteration may have caused osmoregulatory and respiratory difficulties which ultimately led to the observed mortalities.
    • Article

      Occurrence and pathology of Penaeus monodon baculovirus infection in hatcheries and ponds in the Philippines. 

      MCL Baticados, CL Pitogo, MG Paner, LD de la Peña & EA Tendencia - The Israeli Journal of Aquaculture-Bamidgeh, 1991 - Society of Israeli Aquaculture and Marine Biotechnology
      Samples from Penaeus monodon hatcheries (2-3 day old larvae or Zoea 1 to 34 day old post larvae or PL34) and ponds (15 to 159 days old in the pond) were histologically examined for the presence of eosinophilic occlusion bodies in hypertrophied nuclei of the hepatopancreas which is indicative of P. monodon baculovirus infection. The earliest stage found infected in the hatcheries was PL3. Infected shrimp from ponds had slow growth rates and generally pale yellow to reddish brown hepatopancreata. The infection was also characterized by the necrosis and degeneration of the hepatopancreatic tubules with secondary bacterial invasion.
    • Conference paper

      Occurrence of aberrant spermatids in the freshwater sculpin, Cottus nozawae Snyder 

      GF Quinitio & H Takashi - In LM Chou, AD Munro, TJ Lam, TW Chen, LKK Cheong, JK Ding, HW Khoo, VPE Phang, KF Shim & CH Tan (Eds.), The Third Asian Fisheries Forum. Proceedings of the Third Asian Fisheries Forum, 26-30 October 1992, Singapore, 1994 - Asian Fisheries Society
      Light and electron microscopic investigation were conducted on the spermatogenic cell in the testis of the freshwater sculpin, Cottus nozawae. Light microscopic examination showed that two types of spermatids, normal and aberrant, qxisted in the seminal lobule during the regular testicular activity. Both spermaids were mononucleate but the aberrant spermatids ha mor basophilic nucleus than the normal. Aberrant spermatids enlarged and were than released into lumen of the seminal lobules. Ultrastucturally, highly electron-bense granules occurred in the nuclear chromatin of aberrant spermatids. These increased in size becoming the core of chromatin globules which then filled the enlargeed nucleus. The aberrant spermatids when released into the lobule lumen underwent further degeneration.
    • Article

      Occurrence of luminous bacterial disease of Penaeus monodon larvae in the Philippines 

      CR Lavilla-Pitogo, MCL Baticados, ER Cruz-Lacierda & LD de la Peña - Aquaculture, 1990 - Elsevier
      Larval mortalities associated with luminescence have been observed in epizootic proportions in black tiger prawn (Penaeus monodon) hatcheries in Panay Island, Philippines. Luminescent vibrios, identified as Vibrio harveyi and V. splendidus, were isolated from infected larvae but not from uninfected ones. These bacteria were also recovered readily from seawater samples from nearshore areas, the main source of hatchery rearing water. Thus, it is possible that the nearshore seawater is one major source of infection. Pathogenicity tests resulted in significant mortalities of larvae and postlarvae of P. monodon within 48 h of immersion challenge. Scanning electron microscopic observations show that colonization by the bacteria occurred specifically on the feeding apparatus and oral cavity of the larvae, suggesting an oral route of entry for the initiation of infection.
    • Conference paper

      The occurrence of milkfish Chanos chanos fry in Pandan Bay, Antique, from 21 May to 25 June, 1975 

      S Kumagai, AC Villaluz, LB Tiro Jr. & WE Vanstone - In Proceedings of the International Milkfish Workshop Conference, May 19-22, 1976, Tigbauan, Iloilo, Philippines, 1976 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Milkfish fry were collected at the Pandan shoreline and 500 meters offshore. While shore-caught fry were uniform in size those captured offshore varied in size and stage of development.
    • Conference paper

      Occurrence of milkfish eggs in the adjacent waters of Panay Island, Philippines 

      T Senta, S Kumagai & L Ver - In Proceedings of the International Milkfish Workshop Conference, May 19-22, 1976, Tigbauan, Iloilo, Philippines, 1976 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Location of spawning grounds of milkfish is one of the most important steps towards gaining knowledge on the spawning habits of the fish as well as the early life history and nature of its eggs and larvae. The present study is an attempt towards this objective. Surveys were made in selected areas in the sea around the Panay Island and milkfish eggs were collected on several occasions from surface to 20 m depth water by towing with larval nets. The eggs floated in the water in a glass jar. The eggs and newly hatched larvae had the same characteristics as described by Delsman (1929). A comparative study has been made to distinguish milkfish eggs from other more or less similar size pelagic eggs of fishes occurring in the same waters at the same time.
    • Article

      Occurrence of milkfish, Chanos chanos (Forsskal) eggs around Panay Island, Philippines 

      T Senta, S Kumagai & N Castillo - SEAFDEC Aquaculture Department Quarterly Research Report, 1979 - Aquaculture Department, Southeast Asian Fisheries Development Center
    • Article

      Occurrence of milkfish, Chanos chanos (Forsskal) eggs around Panay Island, Philippines 

      T Senta, S Kumagai & NM Castillo - Bulletin of the Faculty of Fisheries, Nagasaki University, 1980 - The Faculty of Fisheries, Nagasaki University
      A total of 551 milkfish eggs was collected by horizontal tows with a fish larval net in the waters around Panay island during the period from April 1976 to June 1979. The maximum number obtained by a single tow was 33 eggs. Most of the eggs were collected from Cuyo East Pass, with some from the waters around the Cagayan Islands and a single egg from the Sibuyan Sea. Almost all the eggs were collected during the period frim March to June, with a peak in April, one month ahead of the peak of fry occurrence.

      Very often milkfish eggs occurred in shallow waters around islands or close to the coasts, while they were sometimes found at locations remote from land and as deep as 900 m. Water temperatures and salinities at locations shere milkfish eggs were found ranged from 26.7 to 30.8°C and from 32.9 to 34.5 ppt. The eggs were rather evenly distributed from the surface to at least 20 m down. The eggs found in the early morning collections were in the early stages of development; those found later in the day were more advanced. It seems that spawning of mikfish takes place at midnight, and that the incubation period of eggs in the wild is about 20 hours.
    • Article

      Occurrence of Polysiphonia epiphytes in Kappaphycus farms at Calaguas Is., Camarines Norte, Phillippines 

      AQ Hurtado, AT Critchley, A Trespoey & GB Lhonneur - Journal of Applied Phycology, 2006 - Springer Verlag
      This paper describes the occurrence of an epiphyte infestation of Kappaphycus farms in Calaguas Is. Camarines Norte, Philippines. In particular, percentage cover of ‘goose bump’-Polysiphonia and ‘ice-ice’ disease, and some environmental parameters that influence the thallus condition of Kappaphycus alvarezii in Calaguas Is. were assessed during 3 separate visits and are discussed.

      Commercial cultivation of Kappaphycus at Calaguas Is. began in the early 1990s. After five years of farming, the stock was destroyed by a strong typhoon. The area was re-planted the following year and production increased annually and reached its peak in 1998–1999. However, the following year, the first occurrence of a Polysiphonia epiphyte infestation occurred concurrently with an ‘ice-ice’ disease. Consequently, annual production and the number of seaweed planters declined rapidly, and this situation persists to the present time. This paper highlights the etiological factors and their consequences.

      Results show that farm-site selection is critical for the success of Kappaphycus production. Characteristics of water movement and light intensity in farming areas contributed to the occurrence and detrimental effect of the phenomenon described as ‘goose bumps’: a morphological distortion of the host seaweed due to the presence of a Polysiphonia sp. epiphyte. A strong inverse correlation was observed between the occurrence of Polysiphonia and water movement: areas with low water motion registered a higher % cover (65%) of Polysiphonia than those in more exposed areas (17%). Although ‘goose bump’-Polysiphonia infestation and ‘ice-ice’ disease pose a tremendous problem to the seaweed farmers, the results of this limited assessment provide a useful baseline for future work.
    • Article

      Occurrence of Vibrio sp. infection in grouper, Epinephelus suillus 

      CR Lavilla-Pitogo, AR Castillo & MC de la Cruz - Journal of Applied Ichthyology, 1992 - Blackwell Publishing
      Vibrio sp., was consistently isolated from grouper, Epinephelus suillus, with bacterial infection. Fingerlings, which were challenged with the bacterium by injection, were highly susceptible. Immersion challenge resulted in 100% mortality within 48 hrs in fish subjected to combination of injury and exposure to the bacterium. Mortality in uninjured fish was observed in the long bath subgroup, but not in the short bath subgroup. These results are correlated with the present practices in the grouper fingerling industry in the Philippines.
    • Article

      Occurrence, characterisation and detection of potential virulence determinants of emerging aquatic bacterial pathogens from the Philippines and Thailand 

      RP Maluping, CR Lavilla-Pitogo, A DePaola, JM Janda & K Krovacek - The New Microbiologica, 2004 - Luigi Ponzio e Figlio Editori
      Strains of Aeromonas spp., 'non-cholera vibrios' (NCVs) and Plesiomonas shigelloides isolated from aquatic environments, fish and human diarrhoeal cases in the Philippines and Thailand were characterised for potential virulence markers. Thus, the production of cytotoxin, cell-associated and cell-free haemolysin and their capacity to adhere to human intestinal (Henle 407) cells in vitro was investigated. In addition, the occurrence of tlh and tdh haemolysin genes and urease activity among V. parahaemolyticus strains was investigated. The results showed that strains recovered from clinical sources (human and fish) produced these virulence factors, whereas these are absent in environmental strains.
    • Article

      Occurrence, histopathology and experimental transmission of hepatopancreatic parvovirus infection in Penaeus monodon postlarvae 

      ES Catap, CR Lavilla-Pitogo, Y Maeno & RD Traviña - Diseases of Aquatic Organisms, 2003 - Inter-Research
      Hepatopancreatic parvovirus (HPV) was detected in samples of Penaeus monodon postlarvae (PL-13, PL-18, PL-19, PL-26) from 2 hatcheries in 2 provinces (Samar and Iloilo) in the Philippines. The percentage of infection was 20 to 100% in postlarvae obtained from the hatchery in Samar in August 2001. Postlarvae from the hatchery in Iloilo, sampled in October and November 2001, had 70 to 99% HPV infection. Wet mounts of squashed hepatopancreatic tissue stained with malachite green (wet-mount technique) and histopathology revealed the presence of large, usually single, basophilic intranuclear inclusion bodies in the distal tubules, which led to displacement of the nucleoli. Light microscopy showed ovoid to spherical inclusion bodies, 5 to 11 µm in diameter. Transmission electron microscopy revealed that the inclusion bodies were composed of electron-dense granular material and virions. The virions appeared roughly spherical and averaged 18 to 22 nm in diameter. An experiment was undertaken to induce HPV infection by feeding P. monodon postlarvae with virus-infected postlarvae. P. monodon postlarvae (PL-16), initially determined as free from HPV, were found HPV-positive 24 h after being fed with infected material. The percentage of infection ranged from 30% at Day 1 post-infection (p.i.) to 100% at Day 7 p.i. determined by the wet-mount technique and by histopathology. This is the first report of a successful horizontal transmission of HPV in P. monodon postlarvae.
    • magazineArticle

      Offshore fish farming 

      Southeast Asian Fisheries Development Center, Aquaculture Department - Aqua Farm News, 1994 - Aquaculture Department, Southeast Asian Fisheries Development Center
      The article discusses about offshore fish farming that is commonly practiced in some countries in Asia, North and South America, and Europe. Environmental factors such as the exposure of the cage to wind and waves, and its management are also discussed.
    • Conference paper

      OIE initiatives on acute hepatopancreatic necrosis disease (AHPND) and other aquatic animal diseases in Asia 

      H Kugita - In RV Pakingking Jr., EGT de Jesus-Ayson & BO Acosta (Eds.), Addressing Acute Hepatopancreatic Necrosis Disease (AHPND) and Other Transboundary Diseases for Improved Aquatic … Diseases for Improved Aquatic Animal Health in Southeast Asia, 22-24 February 2016, Makati City, Philippines, 2016 - Aquaculture Department, Southeast Asian Fisheries Development Center
      The World Organization for Animal Health (OIE) is an intergovernmental organization established in 1924 responsible for improving animal health and welfare worldwide to facilitate safe international trade of animals and animal products while avoiding unnecessary impediments to trade. OIE, as a reference organization of the World Trade Organization (WTO), works to set and update its international standards (OIE Codes and Manuals) regularly through transparent and democratic procedures. The Aquatic Code defines an OIE list of notifiable aquatic animal diseases according to the criteria for listing, which comprise consequences, spread and diagnosis. To be listed, a disease should meet the criteria of each characteristic defined in the Aquatic Code. The acute hepatopancreatic necrosis disease (AHPND) has been officially included in the OIE-listed diseases since May 2015 and officially enforced since 1 January 2016. To fulfill its overall vision which can be summarized by its slogan Protect animals and Preserve our Future, the OIE Regional Representation in Tokyo, Japan and Sub-Regional Representation in Bangkok, Thailand, are working in concert to provide regionally adapted services to OIE Members so that surveillance and control of animal diseases in the region may be strengthened.