nj dolphin necropsy report

8/20/2019 NJ dolphin necropsy report

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US Postal Services: P.O. Box 330 Trenton, NJ 08625

Street Address: 3 Schwarzkopf Drive Ewing, NJ 08628

Telephone: (609) 406-6999

Billing: (609) 671-6404

Fax: (609) 671-6414

www.jerseyvetlab.nj.gov www.state.nj.us/agriculture

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COMPLETE RESULTS REPORT

Case#: 15-1831 MMSC-15-117Marine Mammal Stranding Center Species: Dolphin3625 Brigantine Blvd Breed:Brigiantine, NJ 08203 Age:Referring Submitter: Marine Mammal Stranding Center Sex: Male

Bill To: Marine Mammal Stranding Center Owner: Marine Mammal Stranding C3625 Brigantine BlvdBrigiantine NJ 08203

Date Received: 08/10/15 Date Reported: 10/22/15

Comments

Case summary:

The most significant lesions in this older male bottlenose dolphin

were in the brain. A lymphohistiocytic meningoencephalitis affected

large areas of the meningeal connective tissue even affecting the

choroid plexus. Molecular testing of brain was negative via PCR for

Cetacean morbillivirus in fresh tissue and Brucella sp. in paraffin

embedded tissue. These tests can be negatively affected by sampling

site variation and decreased DNA yield in paraffin embedded tissue.

It is my opinion based on the microscopic lesions observed, that the

changes in the brain were due to a combined infection with both

Cetacean morbillivirus and Brucella sp., especially since this

dolphin tested positive for both of these infectious agents in other

organs. Fresh lung tested positive for Cetacean morbillivirus and

paraffin embedded testis tested positive for Brucella sp.

Additional significant findings included the lesions in the

forestomach, lung, and testicles. There were rare small mucosal

ulcerations in the forestomach that appeared to be healing. Small

abscesses were identified after serial sectioning of the lung andtesticular parenchyma. Microscopically, the lungworms were not

involved in the lung lesions and were considered incidental.

Brucella sp. was isolated from abscessed testicle and was likely

also the cause of the lung abscesses. Angiomatosis was also

identified within the lung and one thoracic lymph node and is a

common finding in Atlantic bottlenose dolphins. Pulmonary

angiomatosis can be extensive and has been speculated to cause

impaired lung compliance, ventilation, and gas exchange. It was not

clear whether the degree of dense fibrosis cause by the condition

would have led to some degree of reduction in respiratory capacity

in this dolphin.

There was also some question whether this was a costal or offshore

bottlenose dolphin. The criteria outlined in the publication by

Mead and Potter from the Smithsonian Institution used to

differentiate these two populations was based on differences in the

shape of the bones surrounding the nares (pterygoid and palatines)

ase No: 15-1831 Page 1 of 5


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and bony lesions caused by the invasion of Crassicauda. Dissection

of these head regions is typically not performed and was

unfortunately not done on this dolphin.

The skin had occasional areas of hyperplasia and mild inflammation

that were consistent with normal scaring associated with raking.

Several sections were examined microscopically, and there was no

suspicion of an infectious etiology.

Overall, this older male bottlenose dolphin was in extremely poor

body condition with no visible thoracic and abdominal adipose

stores, and the gastrointestinal tract was completely empty except

for small amounts of mucus. These findings indicate an extremely

long duration (presumptively months) of decreased caloric intake, if

not anorexia. The lesions within the brain were extensive and very

chronic in some areas. These lesions were the likely cause of the

erratic swimming and other neurologic deficits noted clinically and

also probably made it difficult for the dolphin to catch fish. The

mild wear observed on most teeth would not have impaired

mastication.

Pathology Section

Test: Gross Pathology Specimen Collected on: 08/08/15Verified by: Dr. Angelique Leone Verified on: 10/05/15

Animal ID Test Specimen Result

MMSC-15-117 Post Mortem Whole Body Dead gross pathologyComment: Date of death: 8/8/2015. Manner of death: Euthanasia.

GROSS NECROPSY FINDINGS:GENERAL EXAMINATION: A necropsy is performed on August 10, 2015.The body is that of a 192kg adult male bottlenose dolphin (Tursiopstruncatus) with adequate musculature and severely depleted adiposedeposits in good postmortem condition. The body length measures285cm and the blubber layer measures 1.8cm (dorsum), 1.8cm (lateralflank), and 2.4cm (ventrum). All organs not described are withinnormal limits.

NTEGUMENT/SUBCUTIS: There are occasional linear indentations (rakemarks) on most skin surfaces. The peripheral skin on the fluke anddorsal fin is mildly irregular.THORACIC CAVITY: The abdomen is filled with a small amount(approximately 1L) of thin, clear, light brown fluid.

LUNGS: The pulmonary parenchyma is mottled pink to red withoccasional 3-6mm diameter firm tan foci that occasionally containsmall amounts of soft tan to yellow material. The majority of medium to small caliper airways in both lobes have moderate numbersof 1mm diameter lung worms that measure between 15 to 20 mm inength.CARDIOVASCULAR: The pericardial adipose tissue is not visible.PERITONEAL CAVITY: The abdomen is filled with a small amount(approximately 1L) of thin, clear, light brown fluid. There is novisible adipose tissue within the mesentery or associated witheither kidney.DIGESTIVE TRACT: The forestomach (non-glandular gastric

compartment) has rare 3-5mm diameter mucosal indentations that areined by small amounts of dark brown discolored tissue. All gastriccompartments are empty. The small and large intestines contain onlysmall amounts of bright yellow mucus.TESTICLES: The testicular parenchyma has occasional 3-8mm diameter yellow to light brown discolored foci that are scattered within both



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testicles. These discolored areas range from firm and granular tosoft and oozing small amounts of tan to white material.URINARY BLADDER: The lumen is filled with approximately 300mL of bright yellow mildly viscous urine.BRAIN: The lateral ventricles are partially filled with anrregularly shaped mass composed of soft, tan to dark red mottledtissue.RETENTION OF TISSUES: Routine. Additional sections of lung andbrain are frozen at -20C.PHOTOGRAPHS are taken of external body and major organs in situ.

GROSS DIAGNOSES:Body as a whole: Emaciated, severe.Lung: Pneumonia, granulomatous, chronic, multifocal, mild.Testicle: Orchitis, granulomatous, chronic, multifocal, mild.Thorax and abdomen: Effusion, serous to serosanginous, mild.Lung: Nematodes, mild to moderate.Stomach: Ulceration, chronic, multifocal, mild, forestomach (non-glandular gastric compartment).

Comment: See case summary.

Pathologist: Angelique Leone, VMD

Test: Histopathology Specimen Collected on: 08/08/15Verified by: Dr. Angelique Leone Verified on: 10/12/15


MMSC-15-117 Histopathology Whole Body Dead Completed HistopathologyComment: Microscopic description: Slides 1-16 and Slides A-F. Sections of brain, trachea, lung, thoracic lymph nodes, heart, liver, spleen,skeletal muscle, tongue, urinary bladder, pancreas, andgastrointestinal and reproductive tracts are examined. Major lesionsare described below. Minor lesions are only noted within the finalanatomic diagnoses.

Brain: The leptomeninges overlying large areas of the cortex,cerebellum, and brainstem are mildly to moderately expanded byymphocytes, histiocytes, and rare plasma cells. The vessels withinthese expanded areas of meningeal connective tissue are frequentlymoderately dilated and congested. This leptomeningeal inflammationrarely also superficially extends into the parenchyma. At the levelof the caudal brainstem, the leptomeningeal inflammation alsoextends within the connective tissue surrounding associated nerve

rootlets. Additionally, the caudal brainstem has large bilaterallysymmetrical areas of vacuolation within white matter tracts. Thesevacuolated areas also have occasional vessels that are surrounded byow numbers of lymphocytes, plasma cells, and occasionalneutrophils.At multiple coronal levels, there are areas of perivascular nflammation within Virchow- Robin spaces composed of primarily lowto moderate numbers of lymphocytes, histocytes, fewer plasma cellsand rare neutrophils. These foci are also frequently associatedwith foci of malacia and neuropil rarefaction, have mild gliosis,and are occasionally infiltrated by low numbers of gemistocyticastrocytes. Occasional necrotic neurons are also incorporated into

the lesional areas with gemistocytic astrocytes. Rare presumptiveastrocytes adjacent to these affect areas have approximately 3-4 µdiameter eosinophilic intracytoplasmic inclusions. The caudatenucleus and thalamus are most prominently affected by the areas of malacia and neuronal necrosis.Choroid plexus: The choroid plexus is frequently bordered by



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markedly inflamed leptomeningeal connective tissue. There is alsomarked interstitial fibrosis. The interstitial vessels are severelydilated and congested.Lung: Large areas of the pulmonary interstitium are markedlyexpanded by increased amounts of connective tissue that has numeroussmall caliper vessels (angiomatosis). This change is especiallyprominent in areas of the alveolar tissue immediately adjacent tothe pleura and large vessels. There are also other areas of parenchyma with large consolidated areas infiltrated by numerousneutrophils centrally that are bordered by low numbers of histiocytes and rare multinucleated cells (abscess). Small clustersof alveolar macrophages and/or eosinophilic granular material(edema) are within occasional alveoli adjacent to the abscesses.Occasional bronchioles are filled with adult nematodes (lung worms).The abscesses and bronchiolar nematodes are not concurrent lesions.

Final anatomic diagnoses:Brain: Meningoencephalitis, lymphohistiocytic, chronic, multifocalto coalescing, moderate to severe, with associated choroid plexushypertrophy.Brain: Encephalitis, lymphohistiocytic, chronic, multifocal,moderate, perivascular, with malacia, gliosis, mild neuronalnecrosis, and rare eosinophilic intracytoplasmic inclusions

(presumptive astrocytes).Body as a whole: Emaciated, severe (gross diagnosis).Lung: Abscess, chronic, multifocal to coalescing, moderate.Testicle: Abscess, with mineralization, chronic, multifocal tocoalescing, moderate to severe, with associated lymphoplasmacytic tohistiocytic orchitis.Spleen: Splenitis, suppurative to histiocytic, chronic, multifocal,mild to moderate, with lymphoid depletion and follicular fibrindeposition.Lung: Pulmonary angiomatosis, chronic, multifocal, moderate, withmild multifocal lymphohistiocytic infiltrates.Thorax and abdomen: Effusion, serous to serosanginous, mild (gross

diagnosis).Lung: Bronchiolar nematodes (lung worms), chronic, multifocal,minimal to mild.Kidney: Interstitial infiltrates, lymphohistiocytic, chronic,multifocal, mild, renal pelvis.Thoracic lymph node #2: Angiomatosis, chronic, peripheral, moderate,with moderate to severe lymphoid depletion and mild medullaryhistiocytosis.Trachea: Tracheitis, lymphoplasmacytic, chronic, diffuse, mild,amina propria and submucosa.Epididymis: Epididymitis, lymphoplasmacytic to suppurative, chronic,multifocal to coalescing, mild to moderate, interstitium.Stomach: Gastritis, ulcerative, lymphoplasmacytic, chronic,

multifocal, mild, forestomach (non-glandular gastric compartment).Skin: Erosive dermatitis, suppurative, acute to subacute,multifocal, mild.Skin: Epidermal hyperplasia, chronic, multifocal, mild to moderate,with areas of dermal fibrosis and rete peg anastomosis.Thoracic lymph node #1: Medullary congestion, acute, diffuse,moderate, with mild hemosiderosis.Liver: Lymphoplasmacytic infiltrates, chronic, periportal, mild.Kidney and liver: Congestion, acute, multifocal, mild to moderate.Spleen: Extramedullary hematopoiesis, mild.

Pathologist: Angelique Leone, VMDComments: See case summary.



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Referral External

Test: referral external results Specimen Collected on: 08/08/15Verified by: Dr. Angelique Leone Verified on: 10/05/15


MMSC-15-117 re external results Whole Body Dead see commentsComment: Morbillivirus PCR is conducted at the University of Georgia, AthensVeterinary Diagnostic Laboratory

MMSC-15-117 - Lung is positiveMMSC-15-117 - Brain is negative

Sequencing of the PCR product revealed a 99% similarity to Cetaceanmorbillivirus GenBank accession KP836003.

MMSC-15-117 re external results Whole Body Dead see commentsComment: Testing at the University of Illinois, College of Veterinary

Medicine, Veterinary Diagnostic Laboratory (Zoological section)Sample submitted: paraffin embedded blocks (brain and testis)

Results: Testis is PCR positive for Brucella spp. Brain is PCRnegative for Brucella spp.

End of Report


nj dolphin necropsy report

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