Now showing items 1-9 of 9

    • Article

      Bacterial flora in the hepatopancreas of pond-reared Penaeus monodon juveniles with luminous vibriosis 

      EM Leaño, CR Lavilla-Pitogo & MG Paner - Aquaculture, 1998 - Elsevier
      Quantification and characterization of bacterial flora in the hepatopancreas (hp) of pond-reared Penaeus monodon juveniles affected with luminous bacteria were conducted in 1994 and 1995. Shrimp samples were taken from 23 grow-out ponds, 14 of which had disease outbreaks. Luminous bacterial (LB) load of the shrimps' hp with (mean=2.4×101 colony forming units (CFU)/hp) and without (mean=0.3×101 CFU/hp) disease outbreaks were comparable during the first 15 days of culture (DOC). During disease outbreaks at 18 to 32 DOC, however, LB load of affected shrimps (mean=9.0×104 CFU/hp) were higher than healthy shrimps (mean=7.0×101 CFU/hp). At 50 to 60 DOC, levels of LB were comparable in older shrimps with or without disease. Total viable and presumptive Vibrio counts were also comparable in both shrimp samples from 1 to 60 DOC. Characterization of the 172 bacterial isolates collected showed that most (90.12%) were Vibrio species dominated by V. harveyi (27.91%), V. splendidus II (13.37%) and V. parahaemolyticus (10.46%).
    • Koi herpesvirus-associated mortalities in quarantined koi carp in the Philippines 

      JR Somga, LD de la Peña, CD Sombito, MG Paner, VS Suarnaba, GC Capulos, PI Santa Maria & GL Po - Bulletin of the European Association of Fish Pathologists, 2010 - European Association of Fish Pathologists
      Illegally imported koi carp were confiscated at the Ninoy Aquino International Airport (NAIA), Manila, Philippines by the Fisheries Quarantine and Inspection Service Officers of the Bureau of Fisheries and Aquatic Resources (BFAR). The confiscated fish were turned over to the BFAR Fish Health Laboratory where they were held for observation at a water temperature of 28 degree C. After 5 days, some fish were showing abnormal swimming behavior and some had died. The most prominent disease signs in the freshly dead and moribund fish were body ulcerations and pale gills showing white necrotic patches, consistent with the clinical signs of KHV infection. Gills were dissected and fixed in 95% ethanol. All of the samples tested positive for KHV in a 1-step PCR assay.

      This paper reports the first case of KHV associated mortalities in illegally important koi carp confiscated by the Fisheries Quarantine and Inspection Service Officers of BFAR. This highlights the importance of the quarantine and inspection service s role in preventing the illegal entry of fish into the country and the introduction of exotic aquatic diseases.
    • Article

      Luminescent vibrios associated with mortality in pond-cultured shrimp penaeus monodon in the Philippines: Species composition 

      LD de la Peña, CR Lavilla-Pitogo & MG Paner - Fish Pathology, 2001 - Japanese Society of Fish Pathology
      Heavy mortalities due to luminescent vibriosis have been observed among pond-cultured Penaeus monodon shrimp in the Philippines. The species composition of luminescent Vibrio associated with mortalities was determined. A total of 189 luminescent bacteria isolated from the hepatopancreas of affected shrimps, rearing water and seawater from different shrimp farms in 11 provinces of the Philippines were examined for their morphological, physiological and biochemical characteristics. Results revealed a varied composition of Vibrio species. The most dominant luminescent Vibrio species was V. harveyi (65.5%) followed by V. logei (7%), Photobacterium sp. (6%) and V. orientalis (1%). Some isolates, based on their characteristics, were identified as V. campbellii (16%), V. mediterranei (3%), V. fluvialis (0.5%), V. cholerae (0.5%) and V. splendidus II (0.5%), which are known as non-luminescent Vibrios. V. harveyi is thought to be the major etiological agent associated with the luminescent vibriosis in pond-cultured P. monodon and its pathogenicity was confirmed through intramuscular injection to shrimp. Experimental infection showed that V. campbellii was also pathogenic to P. monodon.
    • Article

      Mortalities of pond-cultured juvenile shrimp, Penaeus monodon, associated with dominance of luminescent vibrios in the rearing environment 

      CR Lavilla-Pitogo, EM Leaño & MG Paner - Aquaculture, 1998 - Elsevier
      Severe mortalities due to luminescent vibrios occurred in pond-cultured Penaeus monodon juveniles particularly in the first 45 days of culture. Luminescent vibriosis epizootics led to reduced shrimp production due to mortalities and slow growth of affected stocks. Monitoring of bacterial population in the rearing water of several ponds was conducted from the time the ponds were flooded with water until 60 days of culture to understand the course of infection. Results showed that the occurrence of mortalities was preceded by a shift of the bacterial profile of the rearing water in infected ponds, notably the dominance of luminescent vibrios. Comparison of bacterial load in the rearing water and water source (river or open sea) showed elevated luminescent Vibrio counts in the former at 12 days to 3 weeks after initial entry of water. Histopathology of affected shrimps showed the hepatopancreas as the target organ of infection where severe inflammatory responses in the intertubular sinuses were seen.
    • Article

      Prevalence of monodon baculovirus (MBV) in wild shrimp Penaeus monodon in the Philippines 

      LD de la Peña, CR Lavilla-Pitogo, CBR Villar, MG Paner & GC Capulos - Aquaculture, 2008 - Elsevier
      Prevalence of monodon baculovirus (MBV) was determined using polymerase chain reaction (PCR) on deoxyribonucleic acid (DNA) extracts from the hepatopancreas of the wild black tiger shrimp, Penaeus monodon collected from 7 sampling sites in the Philippines. These sites are considered as the primary sources of broodstock and spawners used for hatchery operations. MBV was detected from all sites except Palawan during the dry season and Negros Occidental and Bohol during wet season. The prevalence of MBV showed no seasonal, sex and size variations. These results show that MBV is an established viral infection in wild populations of Penaeus monodon in the Philippines. Broodstock collected from the contaminated sites could serve as a reservoir of the virus which could infect the post-larvae used to stock in grow-out ponds.
    • Article

      Prevalence of white spot syndrome virus (WSSV) in wild shrimp Penaeus monodon in the Philippines 

      LD de la Peña, CR Lavilla-Pitogo, CBR Villar, MG Paner, CD Sombito & GC Capulos - Diseases of Aquatic Organisms, 2007 - Inter Research
      Prevalence of white spot syndrome virus (WSSV) was determined using polymerase chain reaction (PCR) methodology on DNA extracted from the gills of wild black tiger shrimp Penaeus monodon collected from 7 sampling sites in the Philippines. These 7 sampling sites are the primary sources of spawners and broodstock for hatchery use. During the dry season, WSSV was detected in shrimp from all sites except Bohol, but during the wet season it was not detected in any site except Palawan. None of the WSSV-PCR positive shrimp showed signs of white spots in the cuticle. Prevalence of WSSV showed seasonal variations, i.e. prevalence in dry season (April to May) was higher than in the wet season (August to October). These results suggest that WSSV has already become established in the local marine environment and in wild populations of P. monodon. Thus, broodstock collected during the dry season could serve as the main source of WSSV contamination in shrimp farms due to vertical transmission of the virus in hatcheries.
    • Conference paper

      Qualitative and quantitative comparison of bacterial flora associated with hatchery-reared and wild-caught shrimp postlarvae 

      CR Lavilla-Pitogo, LD de la Peña & MG Paner - In Proceedings of the International Workshop: Antibiotic Resistance in Aquaculture Environments, 24-25 February 2005, Chiang Mai, Thailand, 2005 - ASIARESIST
      Because of high mortality recorded in pond-reared shrimps due to luminescent vibriosis infection, a study was conducted to determine if postlarvae (PLs) could be major sources of luminescent bacteria (LB). Batches of hatchery-reared (PL12 to 18) and wild-caught Penaeus monodon PLs were examined to determine their bacterial load. Results show that although all PLs have associated Vibrio spp., not all of them harbored detectable levels of LB. Fifty eight percent of wild-caught postlarval batches did not have associated LB compared with only 23-44% of hatchery-reared postlarvae. A significant difference in quantitative LB load was noted between hatchery reared and wild-caught PLs with the former harboring up to 3.0 x 105 cfu LB/postlarva. Wildcaught PLs had only up to 3.5 x 102 cfu LB/postlarva. Antimicrobial sensitivity tests using disc diffusion method show significant resistance to Chloramphenicol and Oxytetracycline among isolates from hatchery-reared PLs (33 and 44%) compared with bacteria from wild-caught PLs (3 and 6%) and near shore seawater (0 and 12%). The differences between the quantitative and qualitative bacterial flora of hatchery-reared and wild-caught PLs may have contributed to the occurrence of luminescent vibriosis in grow-out ponds, which generally make use of hatchery-reared postlarvae.
    • Conference paper

      Studies on the sources of luminescent Vibrio harveyi in Penaeus monodon hatcheries 

      CR Lavilla-Pitogo, LJ Albright, MG Paner & NA Suñaz - In M Shariff, RP Subasinghe & JR Arthur (Eds.), Diseases in Asian Aquaculture I. Proceedings of the First Symposium on Diseases in Asian Aquaculture, 26-29 November 1990, Bali, Indonesia, 1992 - Asian Fisheries Society, Fish Health Section
      One of the major problems in the otherwise highly successful Penaeus monodon hatchery industry in the Philippines is the occurrence of luminescent bacterial disease due to Vibrio harveyi. The possible sources of the bacteria were investigated. Eggs within the ovaries of stage III and IV wild-caught and ablated female P. monodon harbour no bacteria. On the other hand, the midgut contents of these spawners, as well as of pond-reared juveniles, contained numerous luminescent bacteria. Plate counts of the exoskeleton from all sampled females revealed that V. harveyi is a minor component of the exoskeleton-associated flora. Scanning electron microscopy of the exoskeleton showed no significant attached populations. The bacterial loads of Chaetoceros calcitrans, a marine diatom, and Artemia salina nauplii were likewise estimated. C. calcitrans did not harbour V. harveyi at any phase of its growth. Twenty-four-hour-old A. salina appeared to have no resident V. harveyi, but its culture water contained small populations of these bacteria. These data show that the main source of the luminescent bacteria is the midgut contents of the mother, which are shed into the water almost simultaneously with the eggs during spawning.
    • Conference paper

      Swollen hindgut syndrome (SHG) in hatchery-reared Penaeus monodon postlarvae 

      CR Lavilla-Pitogo, MG Paner & RD Traviña - In CR Lavilla-Pitogo & ER Cruz-Lacierda (Eds.), Diseases in Asian aquaculture IV: proceedings of the Fourth Symposium on Diseases in Asian Aquaculture, 22-26 November 1999, Cebu City, Philippines, 2002 - Fish Health Section, Asian Fisheries Society
      In the course of routine microscopic analysis of hatchery-reared Penaeus monodon postlarvae, several batches were found with hindgut abnormalities not previously described in shrimp postlarvae. The abnormality was named swollen hindgut syndrome (SHG) because it affected mainly the hindgut. Postlarvae with SHG showed enlargement and distention of the hindgut folds and its junction with the midgut, although in some cases swelling also occurred in the midgut of the sixth abdominal segment. Over a five-year period, the yearly prevalence of SHG ranged from 6 to 13% of all batches examined. No seasonal pattern was observed as SHG occurred year-round. Despite the numerous samples obtained, SHG has not been associated with specific predisposing factors in the hatchery. The abnormality caused cessation of the rhythmic movements of the hindgut-midgut junction resulting to failure of affected postlarvae to excrete fecal pellets. Swollen hindgut syndrome, although reversible to some extent, caused mortality and significant size variation within batches of postlarvae resulting in their unsuitability for stocking in grow-out farms.