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Ecto and Endoparasites in Tilapia, Oreochromis Niloticus, in Lake Buluan, Tumbao, Sultan Kudarat

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Submitted By katz1443
Words 7437
Pages 30
Chapter I
INTRODUCTION

Background of the Study

One of the major sources of protein in human diet is fish. In fact, marine animals were assumed by ancient writers to be symbols of good health. However, nowadays, marine animals are far from being representatives of good health. They are subjected to diseases just as much as their terrestrial counterparts. Disease, in fishes, is closely linked to environmental stress. In the wild, they generally have some degree of freedom to modify their environment. They can move to more suitable conditions if faced with a negative environmental change such as a reduction in oxygen level. In culture conditions, on the other hand, they have limited opportunity to choose their external environmental conditions.
Most individual fish, may it be in wild or cultivated populations are infected with parasites. The number of parasites necessary to cause harm to the fish varies considerably with the species and size of the host and its health status. Many parasite species are host-specific to at least some degree and are capable of infecting one or only a limited number of host species.
Parasites disease of fish (and livestock) reduces the amount of food available to people around the globe. This is why many researchers mention that it is imperative to investigate the relationship between the environmental factors which affects the parasites that affect production and quality. Even today, it remains difficult to convince governments and other sponsors of research that restriction to species of commercial interest is insufficient in comprehending essential ecological dynamics of life in oceans and coastal waters, developing sound measures of environmental protection, and understanding the principles of biotic diseases.
This study was, therefore, conducted to provide information on the ectoparasites and endoparasites of tilapia in Lake Buluan because of their importance in the artisanal fisheries of Tumbao, Sultan Kudarat.

Objectives of the Study

The study aims to investigate and identify the endoparasites and ectoparasites found inhabiting tilapia in Lake Buluan in Tumbao, Sultan Kudarat at genus level. Specifically, it includes: 1. Identification of the endoparasites and ectoparasites found inhabiting tilapia at Genus level, 2. Observation of weight, length and the common manifestation of ectoparasites Genera and endoparasites Genera, 3. Assessment of the ecto and endo parasites found in tilapia in terms of: 4.1. its physical manifestation, 4.2. clinical signs.

Importance of the Study

Parasite-caused diseases of fish reduce the amount of food available for consumption. For this reason, it is imperative to investigate the types of ectoparasites and endoparasites that is hosted by tilapia found in Tumbao, Sultan Kudarat.
Significantly, this study was conducted for the purpose of investigating and identifying the present parasites inhabiting the tilapia in Lake Buluan in Tumbao, Sultan Kudarat in order to assess its effects to the production and quality of tilapia.

Scope and Limitation of the Study

The study focused on the identification of the endoparasites and ectoparasites inhabiting tilapia from Lake Buluan in Tumbao, Sultan Kudarat.
The study was limited to the observation of 40 tilapias of random sizes from Lake Buluan in Tumbao, Sultan Kudarat.

Time and Place of the Study

The study was conducted in Tumbao, Sultan Kudarat from July 26 to September 13, 2014. Appendix 1 shows the profile and vicinity map of Lake Buluan, Tumbao, Sultan Kudarat.

DEFINITION OF TERMS

To make this research comprehensible, the researcher includes the meaning of the following terminologies:

Area refers to the part of the fish being investigated
Dissect refers to the cutting open of the investigated part of the fish.
Ectoparasite refers to the parasites found in the gills, scales, skin and fins of the fish
Endoparasite refers to the parasites found in the intestines of the fish
Lake refers to Lake Buluan in Tumbao, Sultan Kudarat
Length refers to the measurement of the fish from the tip of the mouth to the tip of tail fin.
Location refers to a part of the fish being dissected
Parasite refers to either endoparasite or ectoparasite or both
Section refers to a part of the fish
Tilapia refers to Oreochromis Mossambicus. The name was adapted from its local name.
Weight refers to the weight of the fish

Chapter II
REVIEW OF RELATED LITERATURE AND STUDIES

This chapter presents the information gathered from related studies and researches, books, encyclopedias, dictionary, articles from internet and handbooks. These gathered information aided the researcher in the formulation of the research problem and the methods to be used for this study.

Parasitism
Parasitism is a relationship between two organisms wherein one organism benefits while the other organism is harmed. The organism which benefits from this relationship is called a parasite while the harmed organism is called the host (Roberts & Janovy 2005). More than half of the millions of species that can be found on Earth are symbionts, which means that most of them live in or on other organisms. Majority of the symbionts are parasites. A parasite consumes the tissues or body fluids of the organism on or within its host. Some of these parasites are pathogenic, meaning that they cause diseases. Parasites typically harm but they do not immediately kill their host. Harm to the host can be caused by tissue damage during the parasite’s various life cycle stages, which in themselves are detrimental to the host, but can also make the host more susceptible to other diseases. At the same time, parasites can also harbor bacteria or viruses and transmit them to the host organism (Lasee 1995). Some parasites are zoonetic, which means that they can be passed from animals to human. This can occur if the animals and human are living closely in the same environment, as well as, human consumption of animal products (Rosas-Valdez & Perez-Ponce de Leon 2011).
Parasites are divided into two distinct groups: ectoparasites and endoparasites. They are categorized according to their physical characteristics, life cycle, and host infection site. Parasites can range in body size from microscopic organisms, such as bacteria and single-celled organisms, to large organisms, such as tapeworms and copepods.
Ectoparasites are located on the external surfaces of the host organism which includes the skin or scales, depending on the fish species, fins and other structures which are considered external, such as the gills, gill rakers, and the oral cavity.
Endoparasites are parasites located within the flesh and cavities of the host organism. These can be found within the muscles, organs, and membrane linings of the cavities in the host organism (Roberts & Janovy 2005).
There is an increased potential on infecting humans with fish endoparasites since tapeworms and roundworms can be passed to humans who eat undercooked or raw meat (Hoffman 1998).

Common Fresh Water Fish Parasites and Its Life Cycle
Water provides the ideal medium for the survival, dispersal and proliferation of disease-causing organisms. Fishes, in particular, are one of the important hosts of parasites in the aquatic ecosystems, harbouring a wide variety of adult and immature forms, acting either as the sole host in a parasite’s life cycle or as one in a series of hosts. Since some parasites are responsible for acute, economically important outbreaks of disease in fish populations, there are some aspects in fish parasitology that is relevant to every modern fish biologist.
Parasitic diseases of fish have a superior position, receiving significant attention in subtropical countries (Eissa, I. et al. 2000). Aside from the parasite’s direct damage on fish tissues, parasitic agents may act as stress factors, rendering the fish to become more susceptible to other diseases (Hoffman et al. 1990). Some parasites reduce the productivity through nutritional effects; others may be responsible for chronic long-term changes in population structure. Infection-associated changes to host phenotype may influence the outcome of intraspecific or interspecific interactions and have important consequences for individual performance, whether measured by an ecologist in terms of evolutionary fitness or by a fisheries manager as reductions in stock biomass. Finally, since some fish parasites are transmittable to humans, and others reduce the market value of fish products by either spoiling host tissues or reducing the demand for fish as food, infections may have socioeconomic or human health importance.
Protozoans
Most of the commonly encountered fish parasites are protozoans. With practice, these can be among the easiest to identify, and are usually among the easiest to control. Protozoans are single-celled organisms, many of which are free-living in the aquatic environment. Typically, no intermediate host is required for the parasite to reproduce (direct life cycle). Consequently, they can build up to very high numbers when fish are crowded causing weight loss, debilitation, and mortality. Five groups of protozoans are described in this publication: ciliates, flagellates, myxozoans, microsporidians, and coccidians. Parasitic protozoans in the latter three groups can be difficult or impossible to control as discussed below. The most devastating fish parasite of all is lchthyophthirius.

Ciliates
Most of the protozoans identified by aquarists will be ciliates. These organisms have tiny hair-like structures called cilia that are used for locomotion and/or feeding. Ciliates have a direct life cycle and many are common inhabitants of pond-reared fish. Most species do not seem to bother host fish until numbers become excessive. In aquaria, whichare usually closed systems, ciliates should be eliminated. Uncontrollable or recurrent infestations with ciliated protozoans are indicative of a husbandry problem. Many of the parasites proliferate in organic debris accumulated in the bottom of a tank or vat. Ciliates are easily transmitted from tank to tank by nets, hoses, or caretakers’ wet hands. Symptoms typical of ciliates include skin and gill irritation displayed by flashing, rubbing, and rapid breathing.
Ichthyophthirius Multifiliis
The disease called “Ich” or “white spot disease” has been a problem to aquarists for generations. Fish infected with this organism typically develop small blister-like raised lesions along the body wall and/or fins. If the infection is restricted to the gills, no white spots will be seen. The gills will appear swollen and be covered with thick mucus. Identification of the parasite on the gills, skin, and/or fins is necessary to conclude that fish has an “ich” infection. The mature parasite is very large, up to 1000 μm in diameter, is very dark in color due to the thick cilia covering the entire cell, and moves with an amoeboid motion. Classically, I. multifiliis is identified by its large horseshoe-shaped macronucleus. This feature is not always readily visible, however, and should not be the sole criterion for identification. Immature forms of I. multifiliis are smaller and more translucent in appearance. Some individuals have suggested that the immature forms of I. multifiliis resemble Tetrahymena. Fortunately, scanning the preparation will usually reveal the presence of mature parasites and allow confirmation of the diagnosis. If only one parasite is seen, the entire system should be treated immediately. “Ich” is an obligate parasite and capable of causing massive mortality within a short time. Because the encysted stage is resistant to chemicals, a single treatment is not sufficient to treat “Ich.”
Chilodonella
Chilodonella is a ciliated protozoan that causes infected fish to secrete excessive mucus. Infected fish may flash and show similar signs of irritation. Many fish die when infestations become moderate (five to nine organisms per low power field on the microscope) to heavy (greater than ten organisms per low power field). Chilodonella is easily identified using a light microscope to examine scrapings of skin mucus or gill filaments. It is a large, heart-shaped ciliate (60 to 80 m) with bands of cilia along the long axis of the organism.
Tetrahymena
Tetrahymena is a protozoan commonly found living in organic debris at the bottom of an aquarium or vat. Tetrahymena is a teardrop-shaped ciliate that moves along the outside of the host. The presence of Tetrahymena on the body surface in low numbers (less than five organisms per low power field) is probably not significant. It is commonly found on dead material and is associated with high organic loads. A common site of internal infection is the eye. Affected fish will have one or both eyes markedly enlarged (exophthalmia).
Trichodina
Trichodina is one of the most common ciliates present on the skin and gills of pond-reared fish. Low numbers (less than five organisms per low power field) are not harmful, but when fish are crowded or stressed, and water quality deteriorates, the parasite multiplies rapidly and causes serious damage. Typically, heavily infested fish do not eat well and lose condition. Weakened fish become susceptible to opportunistic bacterial pathogens in the water. Trichodina can be observed on scrapings of skin mucus, fin, or on gill filaments. Its erratic darting movement and the presence of a circular, toothed disc within its body easily identify it.
Ambiphrya
Ambiphrya, previously called Scyphidia, is a sedentary ciliate that is found on the skin, fins, or gills of host fish. Its cylindrical shape, row of oral cilia, and middle bank of cilia identify Ambiphrya. It is common on pond-reared fish, and when present in low numbers (less than five organisms per low power field), it is not a problem. High organic loads and deterioration of water quality are often associated with heavy, debilitating Ambiphrya infestations.
Apiosoma
Apiosoma, formerly known as Glossatella, is another sedentary ciliate common on pond-reared fish. Apiosoma can cause disease if their numbers become excessive. The organism can be found on gills, skin, or fins. The vase-like shape and oral cilia are characteristic.

Epistylis
Epistylis is a stalked ciliate that attaches to the skin or fins of the host. Epistylis is of greater concern than many of the ciliates because it is believed to secrete proteolytic (“protein-eating”) enzymes that create a wound, suitable for bacterial invasion, at the attachment site. It is similar in appearance to Apiosoma except for the non-contractile long stalk and its ability to form colonies.
Capriniana
Capriniana, historically called Trichophyra, is a sessile ciliate that attaches to the host’s gills with a sucker. They have characteristic cilia attached to an amorphous-shaped body. In heavy infestations, Capriniana can cause respiratory distress in the host.

Flagellates
Flagellated protozoans are small parasites that can infect fish externally and internally. They are characterized by one or more flagella that cause the parasite to move in a whip-like or jerky motion. Common flagellates that infest fish are given below.
Hexamita/Spironucleus
Hexamita is a small (3–18 m) intestinal parasite commonly found in the intestinal tract of freshwater fish. Sick fish are extremely thin and the abdomen may be distended. The intestines may contain a yellow mucoid (mucus-like) material. Recent taxonomic studies have labeled the intestinal flagellate of freshwater angelfish as Spironucleus. The flagellates can be seen where the mucosa (intestinal lining) is broken. They move by spiraling and in heavy infestations, they will be too numerous to be overlooked.

Ichthyobodo
Ichthyobodo, formerly known as Costia, is a commonly encountered external flagellate. Ichthyobodo-infected fish secrete copious amounts of mucus. Mucus secretion is so heavy that catfish farmers popularly refer to the disease as “blue slime disease”. Infected angelfish also produce excessive mucus that can give dark colored fish a gray or blue coloration along the dorsal body wall. Infected fish flash and lose condition, often characterized by a thin, unthrifty appearance. Ichthyobodo can be located on the gills, skin, and fins, however, it is difficult to identify because of its small size. The easiest way to identify Ichthyobodo is by its corkscrew swimming pattern.
Piscinoodinium
Piscinoodinium is a sedentary flagellate that attaches to the skin, fin, and gills of fish. The common name for Piscinoodinium infection is “Gold Dust” or “Velvet” Disease. The parasite has an amber pigment, visible on heavily infected fish. Affected fish will flash, go off feed, and die. Piscinoodinium is most pathogenic to young fish. The life cycle of this parasite can be completed in 10–14 days at 73–77°F, but lower temperatures can slow the life cycle. Also, the cyst stage is highly resistant to chemical treatment.
Cryptobia
Cryptobia is a flagellated protozoan common in cichlids. They are often mistaken for Hexamita as they are similar in appearance. However, Cryptobia are more drop-shaped, with two flagella, one on each end. Also, Cryptobia “wiggles” in a dart-like manner, whereas Hexamita “spirals”. Cryptobia typically is associated with granulomas, in which the fish “walls off” the parasite. These parasites have been observed primarily in the stomach, but may be present in other organs. Fish afflicted with Cryptobia may become thin, lethargic and develop a dark skin pigmentation. A variety of treatments are presently being studied with limited success. Nutritional management has proven to take an active role in its control.

Myxozoa
Myxozoa are parasites that are widely dispersed in native and pond-reared fish populations. Most infections in fish create minimal problems, but heavy infestations can become serious, especially in young fish. Myxozoans are parasites affecting a wide range of tissues. They are an extremely abundant and diverse group of organisms, speciated by spore shape and size. Spores can be observed in squash preparations of the affected area at 200 or 400x magnification or by histologic sections. White or yellowish nodules may appear on target organs. Chronic wasting disease is common among intestinal myxozoans such as with Chloromyxum. “Whirling disease” caused by Myxobolus cerebralis has been a serious problem in salmonid culture. Elimination of the affected fish and disinfection of the environment is the best control of myxozoans.

Microsporidia
Microsporidians are intracellular parasites that require host tissue for reproduction. Fish acquire the parasite by ingesting infective spores from infected fish or food. Replication within spores (schizogony) causes enlargement of host cells (hypertrophy). Infected fish may develop small tumor-like masses in various tissues. Diagnosis is confirmed by finding spores in affected tissues, either in wet mount preparations, or in histologic sections. Clinical signs depend on the tissue infected and can range from no visible lesions to mortalities. In the most serious cases, cysts enlarge to a point that organ function is impaired and severe morbidity and/or mortality results. A common microsporidian infection is Pleistophora, which infects skeletal muscle.

Coccidia
Coccidia are intracellular parasites described in a variety of wild-caught and cultured fish. Their role in the disease process is poorly understood, but there is increasing evidence that they are potential pathogens. The most common species encountered in fish are intestinal infections. Inflammation and death of the tissue can occur, which can affect organ function. Other infection sites include reproductive organs, liver, spleen, and swim bladder. Clinical signs depend on target organ affected but may include general malaise, poor reproductive capacity, and chronic weight loss. A definitive diagnosis of tissue coccidia should be completed with histologic or electron microscopy. Several compounds have been used to control coccidiosis with some success; however, consultation with an experienced fish health professional is recommended. Maintaining a proper environment and reducing stress appear to be important in preventing coccidia outbreaks in cultured fish.

Monogenean Trematodes
Monogenean trematodes, also called flatworms or flukes, commonly invade the gills, skin, and fins of fish. Monogeneans have a direct life cycle (no intermediate host) and are host- and site-specific. In fact, some adults will remain permanently attached to a single site on the host. Freshwater fish infested with skin-inhabiting flukes become lethargic, swim near the surface, seek the sides of the pool or pond, and their appetite dwindles. They may be seen rubbing the bottom or sides of the holding facility (flashing). The skin where the flukes are attached shows areas of scale loss and may ooze a pinkish fluid. Gills may be swollen and pale, respiration rate may be increased, and fish will be less tolerant of low oxygen conditions. “Piping”, gulping air at the water surface, may be observed in severe respiratory distress. Large numbers (>10 organisms per low power field) of monogeneans on either the skin or gills may result in significant damage and mortality. Secondary infection by bacteria and fungus is common on tissue with monogenean damage. Gyrodactylus and Dactylogyrus are the two most common genera of monogeneans that infect freshwater fish. They differ in their reproductive strategies and their method of attachment to the host fish. Gyrodactylus have no eyespots, two pairs of anchor hooks, and are generally found on the skin and fins of fish. They are live bearers (viviparous) in which the adult parasite can be seen with a fully developed embryo inside the adult’s reproductive tract. This reproductive strategy allows populations of Gyrodactylus to multiply quickly, particularly in closed systems where water exchange is minimal. Dactylogyrus prefers to attach to gills. They have two to four eyespots, one pair of large anchor hooks, and are egg layers. The eggs hatch into free-swimming larvae and are carried to a new host by water currents and their own ciliated movement. The eggs can be resilient to chemical treatment, and multiple applications of a treatment are usually recommended to control this group of organisms.

Digenean Trematodes
Digenean trematodes have a complex life cycle involving a series of hosts. Fish can be the primary or intermediate host depending on the digenean species. They are found externally or internally, in any organ. For the majority of digenean trematodes, pathogenicity to the host is limited. The life stage most commonly observed in fish is the metacercaria, which encysts in fish tissues. Again, metacercaria that live in fish rarely cause major problems. However, in the ornamental fish industry, digenetic trematodes from the family Heterophyidae, have been responsible for substantial mortalities in pond-raised fish. These digeneans become encysted into gill tissue and respiratory distress is eminent. Another example of a metacercaria that could cause problems in cultured fish is the genus Posthodiplostonum or the white grub. This has caused mortalities in baitfish, but usually the only negative effect is reduced growth rate, even when the infection rate is high. In cases where mortalities occur, there are unusually high numbers in the eye, head, and throughout the visceral organs. Another fluke is Clinostonum, often called yellow grub. It is a large trematode and although it does not cause any major problems for fish, it is readily seen and will make fish unmarketable for aesthetic reasons.

Nematodes
Nematodes, also called roundworms, occur worldwide in all animals. They can infect all organs of the host, causing loss of function of the damaged area. Signs of nematodiasis include anemia, emaciation, unthriftiness and reduced vitality. Three common nematodes affecting fish are described.

Camillanus
Camillanus is easily recognized as a small thread-like worm protruding from the anus of the fish. Control of this nematode in non-food fish is with fenbendazole, a common antihelminthic. Fenbendazole can be mixed with fish food (using gelatin as a binder) at a rate of 0.25% for treatment. It should be fed for three days, and repeated in three weeks.
Capillaria
Capillaria is a large roundworm commonly found in the gut of angelfish, often recognized by its double operculated eggs in the female worm. Heavy infestations are associated with debilitated fish, but a few worms per fish may be benign.
Eustrongylides
Eustrongylides is a nematode that uses fish as its intermediate host. The definitive host is a wading bird, a common visitor to ponds. The worm encysts in the peritoneum or muscle of the fish and appears to cause little damage. Because of the large size of the worms, infected fish may appear unsuitable for retail sales. Protecting fish from wading birds and eliminating the intermediate host, the oligocheate or Tubifex (soft-bodied worms), are the best means to prevent infection.

Cestodes
Cestodes, also called tapeworms, are found in a wide variety of animals, including fish. The life cycle of cestodes is extremely varied with fish used as the primary or intermediate host. Cestodes infect the alimentary tract, muscle or other internal organs. Larval cestodes called plerocercoids are some of the most damaging parasites to freshwater fish. Plerocercoids decrease carcass value if present in muscle, and impair reproduction when they infect gonadal tissue. Problems also occur when the cestode damages vital organs such as the brain, eye or heart. One of the most serious adult cestodes that affect fish is the Asian tapeworm, Bothriocephalus acheilognathi. It has been introduced to the United States with grass carp and has caused serious problems with bait minnow producers.

Parasitic Crustacea
Parasitic crustacea are increasingly serious problems in cultured fish and can impact wild populations. Most parasitic crustacea of freshwater fish can be seen with the naked eye as they attach to the gills, body and fins of the host. Three major genera are discussed below.
Ergasilus
Ergasilus are often incidental findings on wild or pond-raised fish and probably cause few problems in small numbers. However, their feeding activity causes severe focal damage and heavy infestations can be debilitating. Most affect the gills of freshwater fish, commonly seen in warm weather.
Lernaea
Lernaea, also known as anchor worm, is a common parasite of goldfish and koi, especially during the summer months. The copepod attaches to the fish, mates, and the male dies. The female then penetrates under the skin of the fish and differentiates into an adult. Heavy infections lead to debilitation and secondary bacterial or fungal infections.

Argulus
Argulus or fish louse is a large parasite that attaches to the external surface of the host and can be easily seen with the unaided eye. Argulus is uncommon in freshwater aquarium fish but may occur if wild or pond-raised fish are introduced into the tank. It is especially common on goldfish and koi.

Leeches
Leeches are occasionally seen in wild and pond-raised fish. They have a direct life cycle with immature and mature worms being parasitic on host’s blood. Pathogenesis varies with number and size of worms and duration of feeding. Heavily infested fish often have chronic anemia. Fish may develop secondary bacterial and fungal infections at the attachment site. Leeches resemble trematodes but are much larger and have anterior and posterior suckers.

Fungal Diseases of Fish
Fungi are a group of organisms called heterotrophs that require living or dead matter for growth and reproduction. Unlike plants, they are incapable of manufacturing their own nutrients by photosynthesis. Fungi are present in saltwater or fresh water, in cool or warm temperatures. In most cases, fungi serve a valuable ecological function by processing dead organic debris. However, fungi can become a problem if fish are stressed by disease, by poor nutrition, or are injured. If these factors weaken the fish or damage its tissue, fungus can infest fish. Fungi can also prevent successful hatching when it invades fish eggs. Fungi are grouped by the morphology of various life stages. All fungi produce spores – and its these spores which readily spread disease. The fungal spore is like a seed which is resistant to heat, drying, disinfectants and the natural defense systems of fish. the three most common fungal diseases are Saprolegniasis, Bronchiomycosis, and Ichthyophonus disease.
Saprolegniasis is a fungal disease of fish and fish eggs most commonly caused by the Saprolegnia species called “water molds”. They are common in fresh or brackish water. Saprolegnia can grow at temperatures ranging from 32⁰ to 95⁰F but seem to prefer temperatures of 59⁰ to 86⁰F. the disease will attack an existing injury on the fish and can spread to healthy tissue. Poor water quality (for example, water with low circulation, low dissolved oxygen, or high ammonia) and high organic loads, including the presence of dead eggs , are often associated with Saprolegnia infections. The presence of Columnaris bacteria or external parasites are also common with Saprolegniasis. Saprolegniasis is often first noticed by observing fluffy tufts of cotton-like material – colored white to shades of gray and brown – on skin, fins, gills, or eyes of fish or on fish eggs. These areas are scraped and mounted on a microscope slide for proper diagnosis. Under a microscope, Saprolegnia appears like branching trees called hyphae.
Branchiomyces demigrans or “Gill Rot” is caused by the fungi Branchiomyces sanguinis and Branchiomyces deigrans. Branchiomycosis is a pervasive problem in Europe, but has only been occasionally reported by U.S. fish farms. Both species of fungi are found in fish suffering from an environmental stress, such as low pH (5.8 to 6.5), low dissolved oxygen, or a high algal bloom. Branchiomyces sp. grow at temperatures between 57⁰ and 95⁰F but grow best between 77⁰ and 90⁰F. The main sources of infection are the fungal spores carried in the water and detritus on pond bottom. Branchiomyces sanguinis and B. demigrans infect the gill tissue of fish. Gills appear striated or marbled with pale areas representing infected and dying tissue. Gills should be examined under a microscope by a trained diagnostician for verification of the disease. Damaged gill tissue with fungal hyphae and spores will be present. As the tissue dies and falls off, the spores are released into the water and transmitted to other fish. high mortalities are often associated with this infection.
Ichthyophonus disease is caused the fungus, Ichthyophonus hoferi. It grows in fresh and saltwater, in wild and cultured fish, but is restricted to cool temperatures (36⁰ to 68⁰F). the disease is spread by fungal cysts which are released in the feces and by cannibalism of infected fish. Because the primary route of transmission is through the ingestion of infective spores, fish with a mild to moderate infection will show no external signs of the disease. In severe cases, the skin may have a “sandpaper texture” caused by infection under the skin and in muscle tissue. Some fish may show curvature of the spine. Internally, the organs may be swollen with white to gray-white sores.

Chapter III
METHODOLOGY

This chapter presents the materials that was used for this study. It also presents the proposed conduct of the study and the statistical treatment and analysis to be used in interpreting the data that was gathered during the conduct of the study.

Study Area. The researcher took into account the profile of Buluan Lake provided by the Municipality of Tumbao, Sultan Kudarat. A brief profile of Tumbao, Sultan Kudarat was also taken account. A vicinity map of the study area was also provided. Images of the lake and the fish port was provided, as well, for this study. Sampling. Forty (40) fish samples was bought fortnight, ten (10) fishes per fortnight, for four fortnights from local fishermen at the lake site as soon as they landed and was transported to the laboratory in cool boxes containing ice block. Length and weight was measured.

Examination of Fish for Parasites. A hand lens was used to examine the skin smear of the fish for parasites. The smear was made by scrapping the skin and was observed under the microscope at x40 magnification. The gills was dissected and removed and was examined under the microscope. The cavity of the fish was cut open ventrally. The alimentary canal was also cut opened separately. The contents were washed in a small amount of distilled water into Petri dishes. The samples were examined under the microscope for parasites and the distribution was determined.

Parasite Identification. Parasite identification keys for ectoparasites and endoparasites was created. They were adapted from cited sources. All larval stage parasites were excluded in this study.
An internet search, utilizing educational and governmental institutions, for parasite species names was done to see if the parasite names have changed. If they had been changed, then the new name was listed and dual entries were eliminated. An internet search for images, utilizing the same criteria as for the parasite names, was done and a list of clinical signs was supplied for each of the images. The name of the parasite, clinical signs, and images was gathered and identified for this study.

Data Gathering

For this study, the data observed was gathered and tabulated using the tables below:

Distribution, locations and number of ectoparasites and endoparasites tilapia recovered in Lake Buluan. Parasite | Taxonomic group | Location | No. (%) of fish infected | No. of parasites | range | | | | | | | | | | | | | | | | | | | | | | | | |
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TYPE OF PARASITE:______________________________________
Observed frequency of infected and uninfected males and females tilapia in Lake Buluan. Sex/size | Number infected | Uninfected total | Total | % infected | % uninfected | Males | | | | | | Females | | | | | | Total | | | | | |
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Prevalence of ectoparasites and endoparasites in tilapia by their body weight in Lake Buluan. Body weight (gram) | No. (%) examined | No. (%) infected | Total No. (%) of parasites recovered | | | | | | | | | | | | | | | | |

Chapter IV
PRESENTATION, ANALYSIS, AND INTERPRETATION OF DATA

This chapter presents the results of the investigation, observation and data gathered and the discussion of thee analysis of the data which was useful in achieving the objectives of the study.

Table 1. Distribution and location of ectoparasites and intestinal endoparasites in relation to the weight and length of tilapia recovered in Lake Buluan. PARASITE | TAXONOMIC GROUP | LOCATION | NO. (%) OF | AVERAGE | AVERAGE | | | | INFECTED FISH | WEIGHT (grams) | LENGTH (cm) | ENDOPARASITES | Capillaria | Nematode | Large Intestine | 6 (15.0%) | 140.83 | 17.25 | Camallanus | Nematode | Large Intestine | 3 (7.5%) | 266.67 | 19.67 | AVERAGE | 4.5 {11.25%) | 203.75 | 18.46 | ECTOPARASITES | Clinostomum | Digenea | Gills | 4 (10.0%) | 152.50 | 18.63 | Saprolegnia | Fungus | Gills | 8 (20.0%) | 325.63 | 22.13 | Branchiomyces | Fungus | Gills | 16 (40.0%) | 187.19 | 18.48 | Ichthyopthirius | Protozoa | Gills, Fins | 2 (5.0%) | 162.50 | 19.88 | Flavobacterium | Bacteria | Scales, Gills | 3 (7.5%) | 96.67 | 17.00 | AVERAGE | 6.6 (16.5%) | 184.90 | 19.22 | FINAL AVERAGE | 6 (15.0%) | 190.28 | 19.00 |

Table 1 shows the distribution of the ectoparasites and intestinal endoparasites that was found in the tilapia recovered in Lake Buluan. Among the 40 fishes observed and dissected, 6 fishes at an average weight of 140.83 grams and average length of 17.25cm were infested with Capillaria and 3 fishes with an average weight and length of 266.67 and 19.67, respectively, were infested with Camallanus. Both of the parasites belong to the nematode family and are found in the large intestine area. At an average of 4.5 fishes, an average percentage of 11.25% of the recovered tilapia in Lake Buluan were found to be infested with endoparasites for this study. This means that at a ratio of 40 fishes, 4 to 5 fishes with an average weight of 203.75 grams and average length of 18.46cm will most likely be found to be infested with endoparasites.
Table 1 also shows that 4 fishes which averagely weighs 152.50 grams and averagely measures 18.63cm were infested with Clinostomum of the Digenea family. 8 fishes with an average weight and length of 325.63 grams and 22.13cm respectively were infested with Saprolegnia and 16 fishes averagely weighing 187.19 grams and measures an average of 18.48cm in length were also infested with Branchiomices. Both the Saprolegnia and Branchiomices belong to the taxonomic group Fungus. Clinostomum, Saprolegnia and Branchiomices were located in the gills section of the fish. 2 fishes weighing an average of 162.50 grams and measures an average of 19.88cm in length were infested with Ichthyopthirius, a protozoa, in the gills and skin parts while 3 fishes with an average of 96.67 grams weight and with an average length of 17.00cm were found to be infested with Flavobacterium, a bacteria, in the gills and scales section. This shows that at an average of 6.6 fishes, an average percentage of 16.5% were found to be infested with ectoparasites. This means that at a ratio of 40 fishes, 6 to 7 fishes with an average weight of 184.90 grams and an average length of 19.22cm will most likely be found to be infected with ectoparasites.
Generally, at an average of 6 fishes, a final average percentage of 15% were found to be infested with endo and ectoparasites. This means that at a ratio of 40 fishes, 6 fishes with an average weight and length of 190.28 grams and 19cm respectively will most likely be infested with endo and ectoparasites. With a 15% infestation rate, this indicates that the tilapia population in Lake Buluan in Tumbao, Sultan Kudarat is not heavily infested with parasites.

Figure 1. Capillaria

The Capillarids as a group can infect a wide variety of fish hosts. Capillaria pterophylli is a relatively common nematode seen in the intestines of cichlids. Capillaria species are also seen in cyprinids, gouramis, tetras and other species of fish. One species in particular, C. phillipinensis, found in the intestines of freshwater fish, may cause human intestinal capillariasis if raw or undercooked infected fish is ingested. Capillaria species have direct life cycles, and can spread from one fish to another by ingestion of infective larvae.

Figure 2. Camallanus

Camallanus species infect the gastrointestinal tract of cichlids, live-bearers, and other species of freshwater fish. Camallanus oxycephalus is often seen as a bright red worm extending from the anus. The life cycle of all species that have been investigated involve a cyclopoid copepod crustacean as intermediate host. Development proceeds to maturity in the intestine of the vertebrate with no tissue migration. The worms bear live young which infect the next fish host. Camallanus species are not transmissible to humans or other mammals.

Figure 3. Branchiomyces

The fungus Branchiomyces are found in fish suffering from an environmental stress such as low pH (5.8 to 6.5), low dissolved oxygen, or a high algal bloom. Branchiomyces sp. grow at temperatures between 57⁰ and 95⁰F but grow best between 77⁰ and 90⁰F. The main sources of infection are the fungal spores carried in the water and detritus on pond bottom. Branchiomyces sanguinis and B. demigrans infect the gill tissue of fish. Gills appear striated or marbled with pale areas representing infected and dying tissue. As the tissue dies and falls off, the spores are released into the water and transmitted to other fish.

Figure 4. Saprolegnia

Saprolegnia is a fungus that causes the disease Saprolegniasis in fishes. They are common in fresh or brackish water. Saprolegnia can grow at temperatures ranging from 32⁰ to 95⁰F but seem to prefer temperatures of 59⁰ to 86⁰F. Saprolegniasis is often first noticed by observing fluffy tufts of cotton-like material – colored white to shades of gray and brown – on skin, finss, gills, or eyes of fish or on fish eggs.

Figure 5. Clinostomum

The fluke Clinostonum is often called yellow grub. It is a large trematode and although it does not cause any major problems for fish, it is readily seen and will make fish unmarketable for aesthetic reasons. It is present in freshwater fishes as a larval fluke which forms cream-colored cysts on the gills and under the skin in the mouth.

Figure 6. Ichthyophthirius

A species from this genus, Ichthyophthirius multifiliis, is a common pest in freshwater aquaria and in fish farming. It attacks the epidermis, cornea and gill filaments. It is the largest known parasitic protozoan found on fishes. Adult organisms are oval to round and measure 0.5 to 1.0 mm in size. Grayish pustules form wherever the parasites colonize in the skin. Epidermal cells combat the irritation by producing much mucus. When many parasites attack the gill filaments, they interfere with gas exchange. Fish infected with this organism typically develop small blister-like raised lesions along the body wall and/or fins.

Figure 7. Flavobacterium

The genus Flavobacterium includes pigmented, strictly aerobic, non motile bacteria. They are common in soil and in water. Flavobacterium columnare causes columnaris disease in fish. Fish with columnaris usually have brown to yellowish-brown lesions on their gills, skin and/or fins. The bacteria attach to the gill surface, grow in spreading patches, and eventually cover individual gill filaments. Skin lesions produced by columnaris initially are very shallow and may appear as an area that has lost its natural shiny appearance.

Chapter V
SUMMARY, FINDINGS, CONCLUSIONS AND RECOMMENDATIONS

Summary
The study focused on the identification of endo and ectoparasites found in Oreochromis Mossambicus in Lake Buluan, Tumbao, Sultan Kudarat.
This study was conducted to investigate and identify the endoparasites and ectoparasites found inhabiting tilapia in Lake Buluan in Tumbao, Sultan Kudarat at genus level, to individually observe the weight and length of the fish and the common manifestation of ectoparasites Genera and endoparasites Genera, to assess the ecto and endo parasites found in tilapia in terms of its physical manifestation and clinical signs.
Forty (40) fish samples was bought fortnight, ten (10) fishes per fortnight, for four fortnights from local fishermen at the lake site as soon as they landed and was transported to the laboratory in cool boxes containing ice block. Length and weight was measured. The skin smear of the fish and the dissected gills and the alimentary canal were observed under the microscope at x40 magnification.
The study was evaluated using the identification key for freshwater parasites which was compiled by the researcher from cited sources. Its physical manifestation and clinical signs were also taken into account.

Findings 1. Nematode Capillaria was found to be manifested in the large intestine in 6 fishes with an average weight of 140.83 grams and average length of 17.25cm with no clinical signs other than its presence. 2. Nematode Camallanus was found to be manisfested in the large intestine in 3 fishes with an average weight of 266.67 grams and average length of 19.67cm with no clinical signs other than its presence. 3. Trematode Clinostomum at larval stage was found to be manifested in the gills in 4 fishes with an average weight of 152.5 grams and average length of 18.63 cm with no clinical signs other than its presence. 4. Fungus Saprolegnia was found to be manifested in the gills in 8 fishes with an average weight of 325.63 grams and average length of 22.13 cm with observed clinical signs of fluffy tufts of cotton-like material colored white to shades of gray and brown on the gills. 5. Fungus Branchiomyces was found to be manifested in the gills in 16 fishes with an average weight of 187.19 grams and average length of 18.48 cm with observed clinical signs of striated or marbled gills with the pale areas representing infected and dying tissues. 6. Protozoa Ichthyophthirius was found to be manifested in the gills and fins in 2 fishes with an average weight of 162.5 grams and average length of 19.88 cm with observed clinical signs of small white spots on the gills and fins. 7. Bacteria Flavobacterium was found to be manifested in the gills and scales in 3 fishes with an average weight of 96.67 grams and average length of 17 cm with observed clinical signs of brown to yellowish-brown lesions on their gills, and scales.

Conclusions
Based on the findings, the following conclusions were drawn: 1. Intestinal endoparasites Capillaria and Camallanus were found to be inhabiting the large intestines of an average of 4 to 5 fishes or an average percentage of 11.25% of the recovered tilapia in Lake Buluan with an average weight of 203.75 grams and average length of 18.46cm. 2. Ectoparasites Clinostomum, Saprolegnia, Branchiomyces, Ichthyopthirius and Flavobacterium were found to be inhabiting the gills, fins, and scales of an average of 6 to 7 fishes or an average percentage of 16.5% of the recovered tilapia in Lake Buluan with an average weight of 184.90 grams and an average length of 19.22cm. 3. Parasites Capillaria, Camallanus, Clinostomum, Saprolegnia, Branchiomyces, Ichthyopthirius and Flavobacterium were found to be inhabiting an average of 6 fishes or a final average percentage of 15% of the recovered tilapia in Lake Buluan with an average weight and length of 190.28 grams and 19cm respectively. 4. With a 15% infestation rate, this indicates that the tilapia population in Lake Buluan in Tumbao, Sultan Kudarat is not heavily infested with parasites.

Recommendations
Based on this study, the researcher recommends the following:
1. The residents of tumbao must be fully informed of the presence of the parasites in tilapia as well as the disease it may cause to human health.
2. The local government should further enhance their understanding on the effects of pollution to the parasite infection on the local fish production.
3. The local government should further develop a program on the proper care and culturing of tilapia to reduce the parasite infestation and gain a production of better quality and quantity.
4. For further studies, the researcher would like to recommend on the conduct of a survey on the endo and ectoparasites in milkfish in Lake Buluan.
5. For further studies, the researcher would also like to recommend on the investigation of muscle and tissue endoparasites of tilapia in Lake Buluam.

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