Now showing items 1-18 of 18

    • Article

      Aflatoxin B1 contamination of shrimp feeds and its effect on growth and hepatopancreas of pre-adult Penaeus monodon 

      MN Bautista, CR Lavilla-Pitogo, PF Subosa & ET Begino - Journal of the Science of Food and Agriculture, 1994 - Society of Chemical Industry
      A survey of aflatoxin B1 (AFLB1) levels in commonly used commercial shrimp finisher feeds in the Philippines showed a various range of values from not detected to 120 μg kg−1 using high-performance thin-layer chromatography. Six experimental diets were prepared to contain various levels of AFLB1 based on survey results to determine the effects of such contamination in pre-adult shrimp Penaeus monodon (17.5 ± 0.6 g). Results showed that shrimps fed diets containing AFLB1 greater than or equal to 73.8 μg kg−1 gave comparatively poor growth rate and higher susceptibility to shell diseases. No AFLB1 residues were detected in sampled whole shrimp tissues after 62 days of exposure to AFLB1 containing diets indicating a low potential for transmission of the toxin from edible shrimp tissues to consumers. Histopathological alterations in the hepatopancreas of shrimp chronically exposed to AFLB, were observed in all samples. The degree of alterations correlated with the level of AFLB1. Based on growth performance, pre-adult shrimps can tolerate AFLB1 levels of up to 52.3 μg kg−1 in the feeds although histopathological changes were already evident in the tissues of shrimps given diets with 26.5 μg kg−1 AFLB1.
    • Article

      Agar-digesting bacteria associated with ‘rotten thallus syndrome’ of Gracilaria sp. 

      CR Lavilla-Pitogo - Aquaculture, 1992 - Elsevier
      A condition of the tetrasporophyte stage Gracilaria spp., characterized by white to pinkish discoloration and gradual disintegration of the thallus, has been observed in tank-held stocks. Microscopic observation revealed no fungal or protozoan parasites. Appropriate dilutions of homogenates plated on nutrient agar and bromthymol blue teepol agar showed the presence of bacteria, all of which were agar-digesting, at the rate of 1.42 × 107 cells per g of affected thalli. Colonies on bromthymol blue teepol agar were round and yellow, while those on nutrient agar appeared creamy and round with entire edges, and were rapid agar digesters. The bacteria were Gram negative, fermentative and motile rods. Based on biochemical characteristics, the isolates were classified as belonging to the genus Vibrio. Microscopic observations of thalli cross-sections showed erosion of the pericarp, thus revealing the cortical and the medullary cells. Scanning electron microscopy revealed rod-shaped bacteria, including dividing cells, in affected tissues. Antibiotic sensitivity tests indicated that the bacteria were sensitive to Polymyxin B, nalidixic acid, nitrofurazone and oxytetracycline.
    • Book chapter

      Bacterial diseases 

      EA Tendencia & CR Lavilla-Pitogo - In K Nagasawa & ER Cruz-Lacierda (Eds.), Diseases of cultured groupers, 2004 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Bacteria are very common in the aquatic environment. Most bacterial disease agents are part of the normal flora of the water. They cause disease only when the fish are stressed due to poor environmental conditions, inadequate diet and poor husbandry techniques.

      This chapter focuses on the most common bacterial diseases of groupers.
    • Article

      Bacterial diseases in shrimp (Penaeus monodon) culture in the Philippines 

      CR Lavilla-Pitogo & LD de la Peña - Fish Pathology, 1998 - Japanese Society of Fish Pathology
      The hatchery system for Penaeus monodon evolved from the Japanese community culture system to the modified Galveston method and this shift in culture technique triggered the outbreak of diseases due to opportunistic bacteria. Whereas, sporadic infestation with filamentous bacteria and shell disease were the main bacterial diseases seen in earlier larval culture systems, hatcheries using the modified Galveston method experienced disease outbreaks due to systemic bacterial infection. Although several types of vibrios have been implicated in the epizootics, the dominant species seen were non-sucrose-fermenting vibrios, mainly luminescent Vibrio harveyi. To understand the course of infection, the entry of bacteria in the hatchery was investigated by determining the components and additives which encouraged their growth and dominance. As a result, several approaches to prevent and control bacterial disease have been implemented such as water treatment, hygienic spawning and egg handling, maintaining ecological balance within the system, and chemotherapy. In shrimp grow-out culture, early reports of bacterial problems were limited to shell disease, filamentous bacterial infestation and tail rot. In the last quarter of 1993, however, mass mortality associated with massive bacterial infection in the digestive organ of shrimp started occurring and contributed largely to the collapse of shrimp grow-out activities. An epidemiological study was conducted to understand the spread of infection. Several approaches to prevent or control the problem have been attempted such as the use of reservoirs, water treatment, chemotherapy, maintaining ecological balance within the system through the application of probiotics, and other system modifications.
    • Conference paper

      Bacterial diseases of penaeid shrimps: an Asian view 

      CR Lavilla-Pitogo - In M Shariff, JR Arthur & RP Subasinghe (Eds.), Diseases in Asian Aquaculture II : Proceedings of the Second Symposium on Diseases in Asian Aquaculture, 25-29 October 1993, Phuket, Thailand, 1995 - Fish Health Section, Asian Fisheries Society
      In the past 5 Yr, bacterial diseases have become limiting factors in penaeid culture systems, their effects becoming directly proportional to the growth of the industry in terms of severity and imoact. Although eight bacterial genera have been associated with these problems, only two groups accur quit commonly: filamentous bacteria and vibrios, with the latter beibg more impact. Many Vibrio species have been reported in penaeids: Vibrio alginolyticus, V.cholerae (non-01), V. damsela, V. fluvilis, V.nereis, V. splendidus, V. tubiashii, V. vulnificus, V. parahaemolyticus, and V. harveyi. Interestingly, the last three species, all non-sucrosefermenters, are the most dominat. Diagnosis has beed done mostly through conventional bacteriology and histopathology, although development and use of more rapid detection methods like indirect fluorescent antibody technique, monoclonal antibodies, and other enzyme immunoassays are in demand to improve monitoring and survellance. Because of the conflict between the use of chemotherapeutants and the evironmental hazards that go with it, many researches are now poised on non-medicinal approches to solve bacterial diseases problems.
    • Conference paper

      Bacterial exoskeletal lesions of the tiger prawn Penaeus monodon. 

      GD Lio-Po & CR Lavilla-Pitogo - In R Hirano & I Hanyu (Eds.), The Second Asian Fisheries Forum. Proceedings of the Second Asian Fisheries Forum, 17-22 April 1989, Tokyo, Japan, 1990 - Asian Fisheries Society
      Tank- and pond-reared Penaeus monodon with exoskeletal lesions were examined. The incidence rate was up to 36% for broodstock in concrete tanks and to 20% for pond-reared prawns. The increase in disease incidence was related to prawn age or duration of culture. Bacterial isolation yielded mostly Vibrio spp. Pathogenicity was tested on healthy P. monodon juveniles by a combination of injury and exposure to the test bacteria. Cumulative mortality was 60% within 72 hours in stabbed prawns and 20-40% after 96 hours for superficially-cut prawns. Growth of the bacteria in culture was active in 0.5-8% NaCl and at 12-40 degree C. In-vitro, test isolates were sensitive to chloramphenicol, furazolidone, nitrofurantoin, oxytetracycline and sulfamethoxazole trimethoprim; and resistant to erythromycin, furanace, kanamycin and streptomycin.
    • Conference paper

      Disease management in shrimp farming 

      CR Lavilla-Pitogo - In S Subasinghe & T Singh (Eds.), Production and Marketing of Shrimp: Trends & Outlook. Proceedings of Shrimp 2001 Chennai, The Fourth World Conference on the Shrimp Industry and Trade and Buyer-Seller Meet, 27-29 September 2001, Chennai, India, 2002 - INFOFISH
      Shrimp monoculture systems have been beset with devastating losses due to infectious diseases and environmental deterioration. On a global scale, efforts to make shrimp culture a sustainable industry are warranted because of the high value and demand of shrimp. A Code of Practice for Sustainable Shrimp Farming prepared by the Global Aquaculture Alliance has been adopted by various shrimp producing countries addressing issues like mangroves, site evaluation, design and construction, feeds and feed use, shrimp health management, therapeutic agents and other chemicals, general pond operations, effluents and solid wastes, and community and employee relations.

      Shrimp hatcheries have benefited from technological advances in practically every aspect of rearing including implements to control water quality, eliminate pathogens, and improved nutrition through innovative artificial feeds and supplements. These technologies have made postlarval production very successful, although in many cases, high survival cannot exactly be equated with good quality. Thus a closer look at hatcheries is essential to ensure that rearing protocols match the conditions to which postlarvae will be exposed to upon stocking in ponds. Compiled information on the estimated number of hatcheries and forms in major shrimp growing areas in Asia show a relatively smaller number of small independent hatcheries compared to farms, which demonstrates that effective disease control programmes need to emanate from hatcheries. Presently, three programmes for the hatchery need serious attention. These are (a) the continued implementation of fry analysis procedures, not only as a marketing tool, but so as to exclude pathogenic organisms from ponds, (b) adherence to agreed-upon codes of practice and conformity with accepted guidelines on live transfers to minimise disease spread, and (c) development of a reliable source of domesticated broodstock and incorporating specific pathogen free (SPF) and specific pathogen resistant (SPR) stocks in these programmes to minimise or eliminate dependence on wild broodstock.

      One of the main constraints is the lack of cost-effective and efficient methods to prevent and correct environmental deterioration, and to maintain biosecurity. In addition to providing primary health care, disease control strategies should be a combination of pathogen exclusion and environmental management: the former for primary pathogens such as viruses and the latter for secondary pathogens like bacteria, whose pathogenicity is heightened by environmental degradation and lowered resistance of shrimps. Shrimp forming should start employing systems to manage and lessen waste and the outflow of organic pollutants that could contribute to self-pollution or deterioration of the quality of receiving waters. These include improved feeds and conversion ratios to make feed utilisation more economical and efficient, implementation of recirculating or zero discharge technology, improving the efficiency of aeration systems, improvement of pond siting, understanding of the pond ecosystem and the role of microbes in the environment. In addition to implementing disease control measures and ensuring product quality in various industry sectors, approaches need to be welded together for a holistic approach to health management.
    • Article

      Domestication of the mud crab Scylla serrata 

      ET Quinitio, JJ de la Cruz, MRR Eguia, FD Parado-Estepa, GS Pates Jr. & CR Lavilla-Pitogo - Aquaculture International, 2011 - Springer Verlag
      The significant decrease in wild mud crab population highlights the need to manage the resources and domesticate crabs. This paper presents the initial results of the domestication of mud crab Scylla serrata aimed at producing good-quality captive broodstock. The analysis of the genetic structure of the base population was done as a prerequisite for domestication. Adult S. serrata from the northern to southern parts of the Philippines (Cagayan, Camarines, Samar, and Surigao) were obtained for genetic diversity analysis and domestication. Analysis of molecular variance showed that differences in the genetic variability between the four populations were not significant. Moreover, no significant deviation from Hardy–Weinberg Equilibrium was observed in each sample population and even in pooled populations. Body weight was positively correlated with the carapace width. Second spawning occurred 41–46 days after the first spawning and 34 days from second to third spawning. However, there was a decrease in the number of zoea in repeat spawnings. Twenty-four first-generation (F1) families were produced from the four sites. The duration from spawning of the base population (P0) to attainment of broodstock size F1 was 10–14 months. Four second-generation (F2) families were produced after 11–12 months. Up to the F2, crabs tested negative for six viruses: white spot syndrome virus, infectious hypodermal and hematopoietic necrosis virus, gill-associated virus, yellow head virus, Taura syndrome virus, and infectious myonecrosis virus. The reproductive performance of P0 was comparable to the succeeding generations. Several families were obtained from one population in a year. However, due to the cannibalistic behavior of crabs, more space is required for the nursery and grow-out phase. The domestication of S. serrata is the first study done on any mud crab species in the Indo-west Pacific region. The initial results would serve as guide to understand and eliminate the barriers to mud crab domestication. The breeding technology developed from this study will support the production of good-quality seedstock for farming.
    • Article

      Effects of antioxidants on feed quality and growth of Penaeus monodon juveniles 

      MN Bautista, PF Subosa & CR Lavilla-Pitogo - Journal of the Science of Food and Agriculture, 1992 - Wiley-Blackwell
      Four practical diets were formulated to contain 0.05%, of the following antioxidants: butylated hydroxytoluene (BHT), butylated hydroxy anisole (BHA), propyl gallate (PG) or ethoxyquin (ETHQ). A fifth diet, with no added antioxidant, served as a control. The diets were fed to Penaeus monodon juveniles to determine the effects of antioxidants on feed quality and growth of the animals. The results showed no significant difference (P> 0.05) between the control and the feeds containing antioxidants in 2-thiobarbituric acid values after 0, 30, 60, and 90 days storage, respectively. There was a significant difference by the 120th day of storage, but no signs of physical deterioration were observed in any of the diets. The highest weight gains (704% and 742%) were obtained with shrimps fed diets with BHT and BHA, respectively, as antioxidants. Hepatopancreatic lesion formation was evident with shrimps fed diets containing antioxidants but not with shrimps fed a diet without antioxidant. Shrimps fed with BHT-added feed showed fewest lesions in the hepatopancreas. Although all shrimp samples given feed containing PG and ETHQ showed lesions, these were patchy in nature and did not affect the growth rates of the animals.
    • Article

      L-ascorbyl-2-phosphate Mg as source of vitamin C for juvenile Penaeus monodon 

      MR Catacutan & CR Lavilla-Pitogo - The Israeli Journal of Aquaculture-Bamidgeh, 1994 - Society of Israeli Aquaculture and Marine Biotechnology
      Phosphated ascorbic acid (MAP), a stable vitamin C derivative, was used in practical diets for Penaeus monodon (wet weight, 126-254 mg) as a source of vitamin C. In Experiment I, the levels were from 0 to 1,500 ppm MAP. No significant differences in weight gain, SGR, survival and FCR were observed among treatment means after 92 days of feeding but the lowest values were obtained in the group fed without the MAP dietary supplement. At the start of the experiment shrimps were infected with monodon baculovirus (MBV). However, the histological structure of the hepatopancreas showed improvement in animals fed diets containing 100 ppm MAP and above, after 92 days.

      In Experiment II, shrimps were given different MAP levels (0 to 8,000 ppm) for 81 days. The FCR and survival of shrimps in MAP supplemented diets were significantly higher than those without MAP. In both experiments, shrimps without dietary MAP were weak and developed blackened subcuticular tissues, a symptom of vitamin C deficiency. MAP was utilized by P. monodon as a source of vitamin C. An adequate level in a practical diet would be 100 to 200 ppm MAP, equivalent to 50 to 100 ppm ascorbic acid.
    • Conference paper

      Molecular typing and antimicrobial susceptibility of Vibrio parahaemolyticus strains 

      RP Maluping, CR Lavilla-Pitogo, JL Romalde & K Krovacek - In Diseases in Asian Aquaculture VI, 2008 - Fish Health Section, Asian Fisheries Society
      The aim of the present study was to use three PCR-based techniques for the analysis of genetic variability among Vibrio parahaemolyticus strains isolated from the Philippines. Seventeen strains of V. parahaemolyticus isolated from shrimps and from the environments where these shrimps are being cultivated were analyzed by RAPD, ERIC and REP-PCR. Antimicrobial susceptibility of these strains to selected compounds was investigated using broth microdilution method. Results of this work and analysis of similarity among strains using Dice coefficient and unweighted average pair group method have demonstrated genetic variability within the V. parahaemolyticus strains. The RAPD, ERIC and REP-PCR were found to be suitable typing methods for V. parahaemolyticus. They have good discriminative ability and can be used as rapid means of comparing these strains for epidemiological investigation. However, the REP-PCR analysis yielded a relatively small number of products suggesting that the REP sequences may not be widely distributed in the V. parahaemolyticus genome. Results of antimicrobial susceptibility revealed that resistance among the strains was rare. In conclusion, RAPD, ERIC and REP-PCR techniques are useful methods for molecular typing of V. parahaemolyticus strains. To our knowledge this is the first study of this kind carried out on V. parahaemolyticus strains isolated from the Philippines.
    • Book chapter

      Nutritional diseases 

      CR Lavilla-Pitogo & EC Amar - In GD Lio-Po & Y Inui (Eds.), Health Management in Aquaculture, 2010 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Diagnosis of nutritional diseases is difficult because many signs exhibited by fish are non-specific and most nutritional deficiencies are hard to define. A compilation of data on feed composition and feeding management, as well as husbandry practices, are needed to define a case. Most of data on fish and shrimp nutritional diseases were gathered under experimental conditions. Under farm conditions, most of that definition would be clouded with errors in husbandry practices or secondary infection. Therefore, attempts to diagnose nutritional diseases should be carefully done using every available technique to define the case.
    • 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.
    • 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

      Phylogeographic patterns in the Philippine archipelago influence symbiont diversity in the bobtail squid-Vibrio mutualism 

      RL Coryell, KE Turnham, EG de Jesus Ayson, C Lavilla-Pitogo, AC Alcala, F Sotto, B Gonzales & MK Nishiguchi - Ecology and Evolution, 2018 - Wiley Open Access
      Marine microbes encounter a myriad of biotic and abiotic factors that can impact fitness by limiting their range and capacity to move between habitats. This is especially true for environmentally transmitted bacteria that cycle between their hosts and the surrounding habitat. As geologic history, biogeography, and other factors such as water temperature, salinity, and physical barriers can inhibit bacterial movement to novel environments, we chose to examine the genetic architecture of Euprymna albatrossae (Mollusca: Cephalopoda) and their Vibrio fischeri symbionts in the Philippine archipelago using a combined phylogeographic approach. Eleven separate sites in the Philippine islands were examined using haplotype estimates that were examined via nested clade analysis to determine the relationship between E. albatrossae and V. fischeri populations and their geographic location. Identical analyses of molecular variance (AMOVA) were used to estimate variation within and between populations for host and symbiont genetic data. Host animals demonstrated a significant amount of variation within island groups, while symbiont variation was found within individual populations. Nested clade phylogenetic analysis revealed that hosts and symbionts may have colonized this area at different times, with a sudden change in habitat. Additionally, host data indicate restricted gene flow, whereas symbionts show range expansion, followed by periodic restriction to genetic flow. These differences between host and symbiont networks indicate that factors “outside the squid” influence distribution of Philippine V. fischeri. Our results shed light on how geography and changing environmental factors can impact marine symbiotic associations at both local and global scales.
    • Conference paper

      Shrimp health research in the Asia-Pacific: present status and future directives 

      CR Lavilla-Pitogo - In RP Subasinghe, JR Arthur & M Shariff (Eds.), Health Management in Asian Aquaculture. Proceedings of the Regional Expert Consultation on Aquaculture Health Management in Asia and the Pacific, 1996 - Food and Agriculture Organization of the United Nations
      Shrimp harvests from intensive aquaculture have recently declined in areas which have been productive for many years. Because the most convenient, although not necessarily factual, explanation for these crop failures has been the occurrence of infectious diseases, there is a need to consider shrimp health from a holistic point of view. The classical method used for the study of shrimp disease dealt mainly with identification of the causative organism and the search for methods of prevention and control through chemotherapy. The adverse affects resulting from the use of chemicals in aquaculture have led to a clamor for alternative approaches to disease management. For effective shrimp health maintenance and surveillance, the following components need consideration: development of rapid and sensitive methods for pathogen detection; establishment of shrimp tissue cultures for virology; immunological studies, toxicological studies and drug efficacy evaluation. The epidemiological approach to disease management should augment the classic approach to shrimp pathology, and this calls for multidisciplinary cooperation.
    • Article

      A survey of chemical and biological products used in intensive prawn farms in the Philippines 

      JH Primavera, CR Lavilla-Pitogo, JM Ladja & MR de la Peña - Marine Pollution Bulletin, 1993 - Elsevier
      With attractive prawn export prices and the availability of hatchery fry and commercial feeds, Philippine aquaculture has experienced a shift from milkfish to prawn Penaeus monodon and an intensification from traditional and extensive prawn culture to higher stocking densities. This paper features the results of a survey of intensive prawn farms (n = 21) in Western Visayas and Northern Mindanao conducted in 1990. Average farm size, production, feeding and water management are described. To solve the self-pollution characteristic of intensive ponds, the farms utilized some 40 chemical and biological products; at least another 35 were available in the market at the time of the study. These include therapeutants and disinfectants, soil conditioners, bacteria-enzyme preparations, algicides and piscicides, plankton growth promoters, and feed additives. The possible ecological effects of effluents drained into adjacent marine waters are discussed; some recommendations are given.
    • Conference paper

      Training needs and provision in developing countries of the Asia-Pacific region 

      CR Lavilla-Pitogo - In B Dodet & OIE Scientific & Technical Department (Eds.), The OIE Global Conference on Aquatic Animal Health, Bergen, Norway, 9-12 October 2006, 2007 - Karger
      Training has played a significant role in the development of capacity in aquatic animal health in the Asia-Pacific region where most specialists have fisheries or a background in biology rather than in veterinary medicine. Training courses offered by various organizations, national institutes, universities and the private sector are aimed at providing graduates with skills in disease diagnostics using molecular methods, histopathology, epidemiology, immunology, as well as in disease prevention and control methods. Most training programmes either focus on diseases affecting specific commodities, such as shrimp, marine fish or molluscs, or on diagnostic methods for pathogens such as viruses. Because of the need to train a large pool of geographically dispersed participants, innovative and cost-effective ways of delivery like online and on-site training should be encouraged as well as workshops preceding or following meetings and symposia. One important aspect to be addressed is the translation of training materials to facilitate knowledge transfer to the farm level. Since the inadequate level of aquatic animal health expertise in the Asia-Pacific affects worldwide aquaculture, partnerships between governments, various international organizations and academia should be strengthened in order to fill the training gap.