IAAAM Conference and Workshop Abstracts
IAAAM Archive
IAAAM Workshop

(Ed. Note: The following are the abstracts from the technical presentations delivered on April 24 and 25, proceeding the State of the Art session.)

"Friday," the Hawaiian Monk Seal: A Case History

J.F. Allen, D.B. Mackay, L.R. Taylor, T.R. Sawa, W.G. Gilinartin and G.C. Whittow

A Hawaiian Monk seal, Monachus schauinslandi, was kept in captivity at the Waikiki Aquarium from December 13, 1963, till his death on December 13, 1978. Results of various clinical tests are presented and postmortem findings, including organ weights and measurements, are discussed. While diagnoses of subacute nephritis and hepatitis were made, general senescence is suspected.

The Partially-Consensual Pupillary Light Reflex of the Dolphin

M.C. Barris; W.W. Dawson; C.K. Adams; C.A. Litzkow

Humans and other primates exhibit a consensual pupillary light reflex, i.e., when a light is presented to one eye, the pupils of both eyes constrict equally. Rodents and birds, however, do not have a consensual pupillary light reflex, i.e., the pupil of one eye is not affected by light presented to the other eye. We have simultaneously imaged the pupils of both eyes of two dolphins (Tursiops truncatus) with two independent infrared-sensitive videotape systems. When a light is presented to one eye, the pupil of the stimulated eye constricts more than the pupil of the contralateral eye. This partially-consensual pupillary light reflex has never been reported in other animals. We correlate this reflex with the unusual anatomy of the dolphin midbrain (Jacobs, M. S., Morgane, P. J. and McFarland, W. L. Degeneration of visual pathways in the bottlenose dolphin. Brain Research, 1975, 88, 346-352). This research was supported by NSF grant no. BNS -0147-AOI and NIH training grants I T32 EY 07012 and I F32 EY 05180.

J.E. Beal, Jr.; P.T. Cardeilhac

Ceruloplasmin (CP) is a blue copper containing plasma protein with oxidase activity. Plasma CP levels decrease in humans due to low copper absorption, intestinal and renal protein loss, chronic copper poisoning, Wilson's disease and abnormalities of protein metabolism. CP levels increase in a wide variety of pathological conditions and pregnancy. A radial immunodiffusion (RID) assay was developed by preparing a CP isolate from pilot whale serum and raising an antiserum to it in a rabbit. The antiserum showed no cross reaction with sera from chicken, fish, manatee, elephant seal, human, bovine, equine, porcine, caprine, ovine, lapine, or Brydes (baleen) whale. The antisera did cross react with Pacific pilot whale, Atlantic bottlenose dolphin, pigmy sperm whale, and Pacific white-sided dolphin indicating specificity for odontocete cetacea. Precision of the procedure was measured by running RIDs in quadruplicate for 8 samples; the standard deviations were less that 7% of the sample CP level. Serum samples were obtained from 2 aquariums. Of 61 samples, 32 were considered to be from normal, healthy animals and the mean CP level was 86 mg/dl with a standard deviation of 23 mg/dI. Serum samples were collected from a pilot whale with gastritis (assigned cause of death) believed to be chronic in nature. CP levels were elevated in all samples (mean 130 mg/dl; s.d. 24). (Aided by Marineland of Florida.)

Results and Progress of a Salvage Program Directed Toward Trichechus Manatus

D.J. Black; D.J. Forrester; C.P. Spencer

The West Indian Manatee, Trichechus manatus, is an endangered species with fewer than 1,000 animals remaining in Florida. The information reported here is generated from a salvage program designed to utilize free ranging manatees which are found dead to not only determine cause of death, but gain information regarding some of the animals' biological functions. Topics such as anatomy, developmental osteogenesis, and gross and microscopic pathology will be addressed.

Radiographs of the right flipper have demonstrated the progressive ossification of the bones of the manus, carpals, radius, ulna, and humerus as the manatee increases in length. The interaction of man and manatee accounts for many of the lesions observed, which include superficial scars and collision-related trauma. Infectious diseases, congenital deformities, as well as parasitism may also be the cause of some deaths. The production of a pictorial anatomical guide as well as a tissue reference set will be presented.

P T. Cardeilhac

Cupric ion (copper) is added to marine culture systems to control parasitic protozoans and algae. Mass fish kills from copper poisoning have occurred and the safe upper limit of copper concentration is reported to be 0.2 ppm. Mechanisms of intoxication, other than hypoxia, have been proposed but not identified. In an accidental copper poisoning, 6-10 cultured pinfish and other marine teleosts were exposed to an average copper concentration of 3.3 ppm over a 23 hour period. Signs of intoxication began 6 hours after introduction of copper. Deaths stopped 11 hours after copper concentration decreased to 0.2 ppm, and signs of intoxication stopped 6 hours after the last death. High K+ levels with failure of osmoregulation were found in dying fish. The possibility that potassium intoxication followed copper poisoning was further investigated in a controlled experiment by exposing sheepshead to 8.5 ppm copper for 12 to 17 hours. Stages of intoxication were defined based on behavior and posture. Fish were sacrificed at different stages of intoxication and blood and tissues collected. Twenty-one clinical values were measured and correlated with severity of intoxication.

Increases in serum K+, PO and total intracellular ion values correlated best, and the intoxication appears to be a potassium intoxication produced by cell damage and failure of osmoregulation by gills and kidneys. (Aided by Marineland of Florida.)

Parasitic Diseases of the Hawaiian Monk Seal (Monachus Schauinslandi) from the Northwest Hawaiian Islands

Murray D. Dailey

During the period of 20 April to 17 May 1978 an investigation on Hawaiian Monk Sea] mortality was conducted.

This report concerns the findings dealing with the parasites of this investigation.

Necropsy material was examined from sixteen animals. Two animals were necropsied during the island visit while the remainder (fourteen) were in the form of preserved material recovered previously by two National Marine Fisheries Service Observers (Brian and Patti Johnson).

A total of five species of helminths and one species of acarine were recovered. The helminths were represented by one acanthocephalan (Corynosoma rauschi), three Cestodes (Diphyllobothrium cameroni, D. elegans, D. hians) and one Nematode (Contracaecum turgium). The single species of acarine (under study for identity at present was recovered from a single host infesting the nasal and throat area. Heavy infections of all helminths were found with C. turgium being the most prevalent (in fourteen of sixteen animals) followed by D. cameroni (nine), D. hians (eight), C. rauschi (seven) and D. elegans (three). In addition, thirty-nine stool samples were collected and examined from six of the islands. The ova found were representative of the adults identified with the exception of a capillarid nematode-type egg from Lisianskiis.

Beverly Goven; Donald L. Dawe

Anaphylactic type reactions occurred in channel catfish (Ictalurus punctatus R) and goldfish (Carassius auratus) following immunization and challenge with several protein antigens. The reactions were specific for the sensitizing antigen and could be passively transferred to non-sensitized recipients with serum from sensitized fish. In channel catfish the reaction consisted of disorientation, vertical swimming, increased opercular movement and gasping. In the goldfish the reaction consisted of clamping of the fins except the pectorals, loss of equilibrium, and increased defecation. Some deaths occurred in the channel catfish, but none occurred with the goldfish.

Some Specializations of the Dolphin Eye

W. W. Dawson

Specializations were found in the cornea, ciliary body, lens, retina and optic nerve of the Tursiops eye. Light and interference contrast microscopy disclosed cornea thickness nearly 2 x human. Zonular insertions on the lens capsule are more complex than in human, but specific stains disclosed no significant accommodative musculature in the area of the ciliary body. Golgi stain disclosed both "rod" and "cone" receptor types in the retina] outer layer. Complex specializations of the amacrine cells provide "feedback" pathways across the plexiform layers. Most unusual are giant ganglion cells and their giant axons as seen in optic nerve cross section. These provide for unusually rapid communication between the eye and brain. This research was supported by National Science Foundation grant BNS 75-20147-A01.

Do We Need Vitamin/Mineral Supplementation?

W.H. Dudok van Heel

After more than ten years of consistent vitamin/mineral supplementation, supplementation was suspended in three dolphinaria in March 1978. The hematological results in particular in November '78 and February '79 are the same or better than before, the Killer Whale included. The recovery of a beached Harbour Porpoise is remarkable. The only supplementation is Vitamin B1 and Calcium. It is argued that the addition of this mineral is essential. The animals are fed five different species of fish including squid.

M.P. Dulin

This slide presentation is designed to give the audience a brief panorama on the subject of fish medicine. Representative cases of the more prevalent diseases of marine and freshwater tropical fishes will be projected. Of the infectious diseases afflicting exotic fishes, the following six categories will be discussed: 1. Bacterial, 2. Viral, 3. Fungal, 4. Protozoan, 5. Helminthic and 6. Crustacean. Of the non-infectious or environmental diseases, cases will be projected that depict anoxia, nitrite toxicity, malnutrition, gas-bubble disease and a few examples of poisoning such as cyanide toxicity and ichthyoacanthotoxism. Some basic therapeutic concepts will be mentioned and the importance of ante- and postmortem diagnostic procedures will be emphasized.

Parasites of Manatees (Trichechus manatus) in Florida

D.J. Forrester, D.J. Black, D.K. Odell, J.E. Reynolds, C.A. Beck and R.K. Bonde

From October 1974 to February 1979, 48 East Indian Manatees (Trichechus manatus latirostris) were examined for parasites. Most of these animals represented single strandings and originated from both coasts of Florida, primarily during the winter months. The purpose of this study was to qualitatively and quantitatively characterize the parasite fauna of manatees and to assess the impact of parasitism on manatee populations. The fauna was comprised of four types of parasites: Nasal flukes (Opisthotrema cochleotrema) occurred in 50% of the animals with numbers per animal ranging from 2 to 250. Paramphistome flukes (Chiorchis fabaceous) were found in the intestines and cecae of 76% of the manatees with total numbers as high as 24,000 per animal. A third type of fluke (representing several species in the family Microphallidae) was found in the intestines of a number of animals with up to 132,000 being found per manatee. A fourth parasite, the ascaroid nematode Plicatolabia hagenbecki, was present in the stomachs in numbers ranging from 1 to over 1,600 per animal. The potential impact of these parasites on manatees will be discussed.

Jeannine P. Gilbert; J.B. Gratzek

The objective of this research is to determine the effectiveness of a closed system in fish culture. The system consists of 36 20-gallon tanks whose water is filtered centrally by means of passing rotating biological contactors through a diatomaceous earth filter and finally past a UV sterilizing light before being returned to the tanks. Fish used for the study were channel catfish fingerlings. Selected water quality parameters were measured twice weekly. The expected nitrification cycle was demonstrated. To determine the effectiveness of the central filtration unit and UV light, Ichthyophthirius was added to selected tanks within the system. The parasite spread to all other tanks. This experiment remains to be repeated along with further experiments using virus and bacteria. An infestation of Costia was treated using malachite green and formalin with no ill effects on the biological filter. Further work on all phases of this closed system needs to be done before any conclusions can be drawn.

Fatal Hepatoencephalopathy in a Group of California Sea Lions

W.G. Gilmartin; J.C. Simpson Mary F. Platter-Rieger; Maeve E. Kimball; P.R. Helms

During a period of six days during July 1978, a group of over 40 adult California sea lions came ashore on beaches in Ventura County, California. All of the animals were located from the surf wash zone to the high tide line. They displayed identical symptom-, including paralysis, excessive lacrimation and salivation, absence of a corneal reflex, and occasional severe tonic convulsions. The animals died from a few hours to three days after they beached. Necropsy of seven seals revealed them to be in good flesh and without gross lesions indicating cause for the observed syndrome. Similar histopathology was observed in all cases, believed to be lesions in varying stages of the same disease. The common changes of most significance were in: a) heart myocarditis and edema, b) liver-periportal inflammation and congestion, c) brain changes including satellitosis and neuronophagia and d) lung and kidney congestion. Selected viral and bacteria] cultures were negative. Tissues were not exceptionally high in metals, organochlorine or organophosphate residues. Pathology and symptoms are consistent with a viral hepatoencephalopathy.

Donald E. Griffin

Northern elephant seal stranglings of a particular age group appear to have a high incidence of a debilitating skin disease. This disease has been seen in stranglings received at the California Marine Mammal Center at Fort Cronkhite, California, over the past 3 years. It is characterized by a progression of visible lesions beginning with multiple, elevated, epidermal blebs -- hair loss and hyperkeratization over the bleb area -- cracking and breaking of epidermal integrity over area of lesion -- subcutaneous abscess formation -- sloughing of epidermal and upper dermal tissues. Bacteriology on biopsies obtained in the earlier sequences of the syndrome consistently yields a beta-hemolytic Gp. G streptococcus. In the later sequences, many opportunistic organisms are present, also. These include Candida sp., Pseudomonas sp., and coliforms. Slide documentation will be presented and therapy regimens will be discussed.

Serum Vitamin E Levels in Bottlenose Dolphins: Health Relationships and Functions of the Vitamin

R.D. Gunnels; G.W. Harvey

After encountering low serum vitamin E levels in some captive bottlenose dolphins in Hawaii, a large number of animals were screened to evaluate these levels. Prior to oral supplementation of 900 IU of dl alpha tocopheryl acetate, a group of nine male and female dolphins had mean serum levels of 9.67 ug/ml and 9.20 ug/ml, respectively approximately 6 months of supplementation the mean serum level males was 15.1 ug/ml and the females, 15.3 ug/ml. The average serum level is 11 ug/ml with deficiency syndromes evident at 5 ug/ml. Simultaneously, total serum lipids were determined to evaluate relationship to the serum vitamin E, but these levels were not cantly changed in either sex by supplementation. Analysis for iron was conducted to determine its relation to serum vitamin E. Prior to supplementation the mean serum iron concentrations were 250 ug/dl in males and 303 ug/dl in females. The post supplementation serum concentrations rose slightly to 269 ug/dl in the male group and 322 ug/dl in the female group.

Nicholas R. Hall; Robert D. Schimpff

A relatively high incidence of neuropathology has been found during the course of a five-year study of brain disease in stranded cetaceans. Cerebrovascular, parasitic and non-parasitic infectious processes have been found in a variety of species. The role that such disease plays in causing stranding is difficult to ascertain without knowing the incidence of these disorders in the normal, non-stranded population. Furthermore, whether or not certain types of lesions even result in serious impairment is not resolved. To gain a better understanding of the incidence of parasitic infections involving the brain and auditory system of non-stranded cetaceans, the survey has been expanded to include animals that are caught as a result of the small scale whaling industry continued in St. Vincent by tradition and necessity.

Supported in part by grants from the National Geographic Society and from St. Georges University College of Medicine, Grenada, West Indies.

Mycotic Pneumonia in Green Sea Turtles in Aquaculture

Elliott R. Jacobson; Jack M. Gaskin; Robert P. Shields; Franklin H. White

Juvenile 4-5 month old green sea turtles (Chelonia mydas) were presented with a respiratory disease manifested by buoyancy abnormalities as seen by swimming at an angle to the horizontal. Most animals were thin with consistent plastrona lesions. Necropsy revealed an emphysematous left lung and a consolidated nodular right lung. Histologic examination of the right lung showed multifocal granulomas with a central core of caseated material. GMS staining demonstrated branching septate hyphae within the central core of the granulomas. Sporotrichium sp., Cladosporium sp., and Paecilomyces sp. were cultured from lung tissue of several turtles.

P.T. Cardeilhac; C.M. Walker; R.L. Jenkins; J.M. Popp; D.J. Forrester; F.J. White; R.T. Smith

Attempts were made to formula-rear two abandoned male Florida manatees. Formula consisted of dairy cream supplemented with protein, fat and carbohydrates by adding vegetables, egg yolk and cereal (commercial baby foods), cod liver oil, Sustagen (Mead Johnson) and Casamino-acid (Difco) to provide a calculated composition of 3.5% carbohydrate, 15% fat and 5% protein. Composition of the formula was based on analysis of manatee milk. One infant survived 80 days in captivity and had a mean daily weight gain of 0.86% of body weight over a 5 week period of gain with a mean daily consumption of 900 ml of formula. During this period the infant appeared to be in good condition and clinical values were similar to those found in other apparently normal adult animals; therefore, the formula was considered to be nutritionally adequate. Seventy-five days after capture the infant had a sudden sharp drop in food consumption and died 5 days later. Salmonella heidelberg was isolated from chronic inflammatory lesions of the small intestine. The second infant died 24 days after capture. The animal had numerous ulcers of the skin and acute pneumonia. Both infants were free of parasites. Multiple inflammatory lesions suggested bacteria] infections. Dermatoses and other bacteria] infections are frequently observed in captive manatee, particularly following stress. Antibiotics in the formula may be important to successful rearing.

Thymus Gland in the Harbor Seal (Phoca vitulina): Relationship to Age and Disease

Murray L. Johnson; Steven J. Jeffries; Larry Cargo; M.J. Wicks

The thymus glands of over 70 wild-collected harbor seals were examined to determine what correlation existed between age, sex, season, presence of disease, and other conditions. Collection was by fire-arm. Complete evaluations including gross and histopathology examinations, blood counts and chemistries were done. Aging was done by tooth section. The presence of disease was determined by the presence of gross or microscopic evidence of parasites and other abnormalities, and this correlated with the weight of the thymus glands. Thymus glands were found to be large in comparison with usual mammalian norms. A high degree of parasitism, especially heart worms, was found. Lipogranulomatosis of the liver was very common. Despite some positive correlations, the reasons for persistently enlarged thymus were not satisfactorily explained.

G.W. Jones

The use of a biological filter to help control water quality and an antifungal drug Ketoconazole has been successful in controlling and treating Candidiasis in a group of Tursiops truncatus. The biological filter reduced the amount of chlorine needed to maintain acceptable water quality. It was felt that chlorine in the system encouraged Candidiasis by altering the normal bacterial flora of the animal's skin and caused additional stress on the animals. A discussion of how the biological filter was adapted to the system and how well it functioned will be presented. Ketoconazole proved to be effective in treating active cases of cutaneous Candidiasis. The case reports of two animals that received Ketoconazole will be discussed.

Exotic Fish Problems in the U.S.

James A. McCann

In August 1977 the Secretary of Interior authorized the U.S. Fish and Wildlife Service to establish a Research Laboratory in Gainesville, Florida to develop a national research program on exotic fishes which have been or are likely to become established in U.S. waters. A preliminary survey in 1977 found that 43 species of exotic fish have established viable self-sustaining populations in the U.S. Twenty-six of them are presently established in Florida with 5 species showing a major expansion in distribution during the last 6 years. Some of these species have created or are likely to create adverse impacts on the native fishes or their habitats. The laboratory will support the Service's efforts to stop further introductions of injurious species, determine the behavior and life histories of all established species, evaluate their actual or potential impact on the nation's aquatic ecosystems and develop a series of protocols to fully evaluate the beneficial or harmful characteristics of any new exotic fish being considered for introduction into this country. Research contracts are presently being funded to inventory the native and nonnative fishes in North America and to determine the status, distribution and impacts of the non-native fishes presently found in the open waters of Florida.

S. Nakeeb; B. Babus; D. Velle

Candidiasis is a common problem in captive bottlenose dolphins and often fatal. Available treatment methods are not successful. A new medicine, "Ketoconazole," (PM3-41,400) was used in treating a progressive case of cutaneous candidiasis in a three year old female bottlenose dolphin. A daily oral dosage of 20 mg per kg body weight given in four divided doses for five days showed remarkable recovery. No clinical manifestation of toxic effect was noticed in the eighteen day course of treatment. Pre and post treatment hematology and blood chemistry did not reveal significant changes. Ketoconazole is a very promising drug for the control of candidiasis in dolphins.

Nasal Passage of Stomach Tubes in West Indian Manatees

F.C. Neal; A.B. Irvine

Five sonic thermistors (14x57 mm, weighing 9.1 gms) were inserted into the gastrointestinal tract of 3 captive manatees (Trichechus manatus) to monitor core body temperature during metabolic studies. Preliminary attempts at oral passage using an equine balling gun were met with vigorous resistance by the manatees and damage to one thermistor. Subsequent nasal passage of a stomach tube (19 mm OD x 12 mm ID) was accepted without a struggle by the manatee. A thermistor, held in the tip of the tube, was passed through a nostril into the esophagus (total distance 40 cm). The thermistor was gently forced from the tube by passing a probe through the lumen of the tube. Thermistors were swallowed and passed through the gastrointestinal tract in 6 to 20 days. Manatees appeared to have normal respiration while the tube was in place.

Stomach tube passage through nostrils preferred to the oral route for introducing materials (thermistors, drugs, etc.) into the gastrointestinal tract of manatees.

Clinical Data from Free-Ranging and Captive West Indian Manatees (Trichechus manatus)

F.C. Neal; A.B. Irvine; K.C. Bachman; R.L. Jenkins

Brief discussions on the following subjects will be presented:

 Blood and urine values in free-ranging and captive manatees.

 Body temperature responses to cold environments.

 Composition of manatee milk during late lactation.

 Skin lesions in captive manatees.

 Freeze branding of manatees for identification in field studies.

Antibiotics and Aquatic Bacteria

K.E. Nusbaum; E.B. Shotts, Jr.; Deborah Talkington

The minimum inhibitory and minimum bacteriocidal concentrations (MIC, MBC) of four common aquatic bacteria (F. columnaris, A. hydrophila, A. salmonicida, and P. fluorescens) were determined for four commonly used antibiotics (tetracycline (TC), chloramphenicol sodium succinate (CH), erythromycin (ER), and Furanace (FU). While the authors concluded TC and FU to be the most effective, they also found that the pharmacological preparation and environmental influences are crucial in the selection of an appropriate antibiotic. The need for identification and sensitivity testing previous to antibiotic administration is illustrated by resistant agents and plasmid testing.

Use of Synthroid® to Reduce and Prevent Goiter in Sharks

John B. Sciarra

A brief observational study was made to determine if Synthroid® synthetic hormone, could reduce and prevent goiter in two species of elasmobranchs. Four sharks showing swelling in the pharyngeal region and one not were injected intramuscularly with dosages of Synthroid from .2 - .45 mg arbitrarily according to estimated weights. Each of the sharks showing swelling were reduced or eliminated within weeks following treatment. The shark not showing swelling in the same system has not shown signs of developing goiter.

Emmett B. Shotts; Jr.; Wayne Jones; F. Deborah Talkington

A study was made of the microflora associated with the spiracles of a group of twenty captive dolphins. The results of this investigation indicate that a number of both Gram-positive and negative organisms may be found at this anatomical site. Coagulase positive Staphylococci (60%) were the most common organism isolated. Other organisms included alpha streptococci (2.5%), Pseudomonas aeruginosa (5%), Pseudomonas putrifaciens (5%), Corynebacteria (2.5% and Candida spp (47%). These flora will be discussed as they re late to comparable flora from similar sites in domestic animals.

Ecological Investigations of Petroleum Production Platforms in the Central Gulf of Mexico: Histopathology of Marine Fish

R.F. Sis; N.H. McArthur; G.G. Stott; R.J. Tarpley; V.L. Jacobs; W.E. Haensly

Six tissues (muscle, liver, stomach, gonad, kidney, gill) from each of 2 species of benthic or platform associated fish were examined microscopically for histopathologic conditions. A total of 1440 specimens (6 tissues x 5 fish x 2 species x 24 stations) were collected from 20 oil producing platforms and 4 control stations in the north-central Gulf of Mexico. The objectives were to describe pathologic conditions and to ascertain any correlation with their proximity to production platforms. This work was part of a broad project which also included studies of hydro-graphy, hydrocarbons, sediments and biota trace metals, microbiology and invertebrate histopathology. The following conditions were observed in all six tissues: protozoa, helminths and acidophilic granular cells. Less frequent observations were: hyperplasia of the gill filaments, vasocongestion (gill), edema (gill), leukocytosis (liver, gill), fatty, infiltration (liver) and chromatophores (liver, kidney, stomach). These are preliminary observations, the final data synthesis has not been reported.

Problems in Farming Ornamental Fish in Florida

Ross B. Socolof

Mr. Ross Socolof is one of the leading ornamental fish culturists in .the world. He has been asked by the IAAAM program committee to review selected major problems in the production of ornamental fish in Florida. Mr. Socolof is active in the day to day operation of Four Star Fish Farm in Bradenton, Florida.

L.R. Udey

Eubacterium tarantellus was previously shown to be associated with fish kills in Biscayne Bay and the Texas Gulf Coast. The organism was primarily isolated from the brains of dead and moribund fish. We postulated that the anaerobe was harbored in a carrier state in the brains of fish and that clinical manifestations were stress associated.

Twenty-four fish species from Biscayne Bay and the surrounding ocean waters were sampled to determine the incidence of E. tarantellus in the brain, liver, kidney, spleen and intestines of clinically healthy specimens. In addition, the number of E. tarantellus per gram of brain tissue was determined for one species.

Thirteen of the species harbored the anaerobe in the brains. Although some specimens had the anaerobe in other organs, the incidence was low; no fish had the organism in other organs if its brain was not infected. Juvenile Eucinostomus gulu brains contained only 20 to 250 bacteria per gram of tissue.

Function of the Skin and Fatty Acids of the Northern Fur Seal (Callorhinus ursinus) as a Natural Barrier to Fungal Penetration

N.A. Vedros; Alayn Waldorf; .W. Smith

Fungi are ubiquitous in the Pribilof Rookeries but Frank Dermatophyte infections are rare. A detailed examination of the skin by Histology, depot fat by GLC, and in vitro inhibition of selected dermatophytes by certain fatty acids was made. The deep stratum corneum, interlamellar lipids, and tight collar of keratinized cells in the follicle shaft appear to aid in preventing fungal penetration. The fat contains greater proportions of C:15 and short chain fatty acids than other seal species. The short chain fatty acids were capable of inhibiting Autochthonous Dermatophytes in vitro. The role of various factors which might interfere with this balanced parasitism is discussed.

Linda Werner; R. Halliwell; D. Buesse

Recently, an immune potentiating drug, levamisole phosphate, has proven efficacious in achieving regression of skin lesions in dolphins with Candida Albicans (CA) infection suggesting that immune deficiency might contribute to the patho-etiology of this disease. Immunocompetence was evaluated in 5 groups of dolphins using lymphocyte transformation (LT), and skin test challenge with CA extract. The test groups included normal dolphins in captivity, normal dolphins medicated with levamisole, dolphins with CA lesions, dolphins in remission from previous CA -infection and dolphins procured from natural habitat. Intradermal challenge with CA extract resulted in positive delayed hypersensitivity reaction in all dolphins except those procured from natural habitat. LT experiments showed normal responses in all groups tested when fetal calf serum (FCS) was used in the nutrient media. Serum from dolphins with disseminated CA suppressed LT completely, while serum from a dolphin who's disseminated CA was eliminated with systemic antifungal therapy was no longer suppressive to LT. These results indicate that immune deficiency may be acquired with chronic CA infection, and not necessarily a primary or predisposing factor. Immune suppression constitutes a rationale for the Use of levamisole in conjunction with specific antifungal therapy. Environmental factors must not be ignored. Skin test results and the increased incidence of CA infection in artificial environments indicate that there is greater exposure, and perhaps increased susceptibility compared to the natural environment. The above conclusions are convincing evidence that the etiology of CA infection in dolphins is multifactorial, that altered environment may introduce predisposing factors and that acquired immune deficiency may account for disseminated infections refractory to conventional modalities of therapy.

Use of Electron Microscopy to Study Spermatogenesis in an Estuarine Fish (Lagodon rhomboides)

J. Winstead

The fine structure of germ cells from the pinfish, L. rhomboides, is described. Mature pinfish testis were fixed in phosphate buffered glutaraldehyde and osmium tetroxide and examined with electron microscopy. Spermatogenesis in L. rhomboides is similar to other teleosts and resembles spermatogenesis in mammals. Germ cells proliferate from the walls of seminiferous-like tubules in the normal mitotic and meiotic sequence common to all vertebrates. Spermatogenesis in Lagodon occurs within cysts created by cyst epithelial or Sertoli cell homologues. Germ cells progress through the maturation cycle with all cells in the same stage of development. Cyst epithelia] cells maintain the germinal environment and phagocytize cast out debris from maturing germ cells. Attention is being given to the morphological processes involved in cellular organization, growth and differentiation in normal and abnormal development. Ultrastructural studies of fish reproductive systems could give researchers and aquaculturists better understanding of the mechanisms responsible for important fishery related phenoma such as hybrid vigor, sterility, early stage survival and population stability.

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