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Introduction to Koi Medicine and Surgical Techniques. Dr. Kari Nugent Dr. Katie Waters. All about Koi. NOT COY Cyprinus carpio , the “ornamental carp” Developed by the Japanese over 200 years ago.
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Introduction to Koi Medicine and Surgical Techniques Dr. Kari Nugent Dr. Katie Waters
All about Koi.. • NOT COY • Cyprinus carpio, the “ornamental carp” • Developed by the Japanese over 200 years ago. • Selectively bred for color, pattern, size and confirmation
Koi are NOT big goldfish! Goldfish Koi
Not here… Spring Break 2002: BAHAMAS
Koi fish are becoming a popular “hobby pet” Koi ponds help relieve stress Great addition to natural ponds “Fun to feed” Why Koi?
Basic Needs • Ideal water temperature is 20 degrees Celsius (68 degrees Fahrenheit) • Good water quality • Proper filtration system • Adequate oxygenation • Proper Diet • Don’t overcrowd!
Common causes of stress include Poor water quality High ammonia levels Crowding Parasites / Predators Wrong temperature Poor diet Toxic chemicals Koi don’t handle stress well…
Koi can blush! • Koi show stress by blushing red in their fins and on their bodies. • Common sites include the front spines of dorsal fins, the caudal fin, and under the scales.
The Basics of Koi Medicine • A good history is critical in every species!
Important Koi Questions • How long have you been keeping koi? • What are the problems with the fish today? • When did you first notice these problems? • How long have you owned the sick koi and where did they come from? • Are there other fish in the same tank or pond with the sick fish, and if so, how are they doing?
History, continued • What is the size of the pond and how is it heated, filtered, and aerated? • Do you have a water test kit? • How often do you test the water? Current results? • What and how often do you feed your fish? • Have the fish already been treated? If so, with what medications? • Any risk of toxic exposure?
Testing the water… • A good water testing kit should determine: • Water temperature • Ammonia levels • Nitrate / nitrite levels • pH • Dissolved O2 content • Total alkalinity • Other levels (copper, chlorine, etc)
Common Koi diseases • Bacterial infections • Mostly Gram – organisms • Aeromonas or Pseudomonas • Commonly present as • Mouth or fin rot • Body sores • “Redbelly” • Sudden death • Bulging eyes • Dx: Blood tests and/or necropsy • Treat with antibiotics? “Dropsy” Red Mouth Rot
Common Koi diseases (cont’d) • Parasite Infections • Often found concurrent with a bacterial infection • Easy to diagnose with a microscope • Requires a skin/fin scrape – not so easy… • Sample collection often requires anesthesia • Often easy to treat
Common Koi Parasites • Skin / Gill Flukes • Cause ulcer disease • Treat with potassium permanganate • “Ich” (Ichthyophthirius multifilis) • Protozoal killer of very small fish • “Redskin” disease • Not the usual “white spot” syndrome • Clears easily with salt
Other Koi parasites • Trichodina • “flashing” – spiderweb skin lesions • Chilodonella • Springtime killer • Visible parasites • Anchor worm • Argulus (aka “fish lice”)
Koi Fungal Infections • External, often secondary to break in epidermis and mucus coating • Dx: skin or fin biopsy • See hyphae / spores with microscope • Treat with supportive care, topical antibiotics and/or disinfectants • Good water quality is key! • High water temperatures, nitrate levels, and crowding promote infection!
Common diagnostic procedures • Blood collection • Culture, CBC, serum chemistries • Caudal vein site • Biopsy • Requires sterile scalpel blade, scissors and forceps • May require anesthesia • Must consider size/condition of fish • Fecal exam • Useful to detect internal parasite problems
More diagnostic procedures • Radiology • Often no anesthesia required • CT scans, bone scans, contrast studies • Necropsy • Allows thorough examination of tissues • Any/all organs available • Caution – dead fish autolyze rapidly, so best to perform necropsy immediately after euthanasia
Surgical Procedures on Fish • biopsies (liver and kidney) • mass removals • swim bladder surgery • egg impaction • celiotomy • enucleation • gonadectomy
Surgery? Avoid surgical procedures in fish that: • Have scales raised all over their body • Have not eaten in 6-8 weeks • Have scoliosis • Display generalized weakness • Have chronic water quality issues “Dropsy” – the pinecone look
Special Considerations • careful handling to maintain protective cutaneous coating • fish skin is easily damaged • constant mucus production • Makes asepsis difficult • fish should be kept moist during surgery – DUH!
Surgical Preparation • withhold food for 24-48 hours (no need to withhold water) • Administer anesthesia to a surgical plane • Sponge mucus from surgical sight • Drape fish with a soft, absorbent, moistened drape. • Monitor patient with a pulse Doppler or ECG leads
Anesthesia delivery • Immersion • Injection into the musculature • Injection into the peritoneal cavity
Available Anesthetics • MS 222 • urethane • haltothane • isoflurane • clove oil • butorphenol Most tooth ache remedies are 85% Eugenol (clove oil) –use three drops/gallon
MS 222 • FDA approved for consumable fish • 21 day withdrawal • sodium channel blocker • 25-100mL/1L of water • induction time 1-3 minutes • recovery time 3-15 minutes • excellent maintenance • may contribute to hypoxemia, hypercapnia, resp. acidosis in some species
Eugenol (clove oil) • practical alternative to MS222 • readily available • 25-50mg/L water • recovery may be prolonged • dilute 1:10 in 95% ethanol • similar complications as MS222, slightly lower safety margin
Isoflurane • bubbled through anesthetic chamber to effect • induction time 1-3 minutes • recovery time 3-15 minutes
Butorphanol • given IM • dosage 0.4mg/kg • administer prior to recovery • insures better recovery
Post Operative Care • place fish in untreated water in holding tank • move gently and slowly to enhance opercular movement • avoid moving too quickly • Monitor for at least 24 hours
Induction Chamber • Anesthesia – Isoflurane, 5cc/2gallons of water. • Patient’s own water was used in the induction chamber.
Egg Impacted Female • Dilute induction water to 1cc/gallon • Pump water from induction chamber over the gills.
Groucho Before surgery the weight of the mass on Grouchos head made swimming and eating difficult.
Groucho before surgery • large mass on dorsal thorax • diagnosis – fibroma • presented to Oklahoma State University Aug. 15,2001 • physical exam findings: large, round mass, with tremendous blood vessel infiltration.
Groucho during surgery Anesthesia was maintained by infused water flow through the mouth and over the gills.
Groucho at Home Three weeks after his surgery
Laser surgery? • Lymphoma on the dorsal fin • Treatment option – laser removal.
References • http://www.koivet.com/ • http://www.ulam.umich.edu/UCUCA/anesthesia_fish.doc • http://www2.okstate.edu/pio/Groucho.html • http://www.cvm.okstate.edu/Depts/VCS/ZEW/ZEW%20Goldfish%20Case.htm • http://www.welbornpet.com/Presentation/FishTumor/fishp6.htm • http://www.geocities.com/Tokyo/4468/swmbldr.html • http://www.vcnet.com/coi_net/ • http://www.coloradokoi.com • http://www.nwkg.tripod.com/