Nothing. Extreme accentuation of sinus arrhythmia (bradycardia), markedly slower during expiration is a normal finding in brachycephalic breeds. No treatment needed if dog is not symptomatic.
SYMPTOMATIC animals would present with fainting, weakness. If respond to an atropine test, consider Med Rx with Glycopyrrolate, Propantheline (Pro Banthine ®), Isoproterenol. If poor response, may need a pacemaker.
Refs: Blackwell's 5-Min Vet Consult Canine Feline, 4th ed. pp.1262-3, Pasquini's, Tschauner's Guide to Small Animal Clinics, vol 1, 2nd ed. pp. 255-6 and the Merck Veterinary Manual online edition.
It is 89%. Remember: you are comparing TWO TESTS here. PVP means "Of the turtles my test says are positive (27), how many are truly positive?" (27-3=24, this # goes in the "a" box)
Here is how you do it: First, draw a 2x2 table, and label the boxes a,b,c,d. PVP = a/(a+b). Click here to see a Basic 2X2 table. Now, add in the TOTAL number of animals (100), the total positive by YOUR test (27) and the total negative by YOUR test (73), like this diagram: 2x2 with totals.
Now the (slightly) tricky part. Add in the numbers that YOUR test got WRONG according to the gold standard test. (3 false pos in box b, 10 false neg in box c): Click here to see 2x2 with b and c cells.
Last, subtract to fill in your "d" box (73-10=63) and do the math to calculate PVP = a/(a+b)=24/27=0.89 or 89% : Click here to see the final 2x2 with all cells filled and PVP calculated.
FYI: You can calculate sensitivity a/(a+c), specificity d/(b+d), Predictive Value POS (PVP) a/(a+b) and Predictive Value NEG (PVN) d/(c+d) with the same 2x2 table.
Path we said:
Unkempt coat: parasitic, metabolic, allergens, autoimmune, weather, husbandry
Patchy alopecia - parasites, fungus, bacteria, endocrine/metabolic
Pruritis - parasites, bacterial, fungal, allergies, neurogenic, metabolic
Crusting of extremities - see above list, extremities! Important.
Parapoxvirus - crusting around the mouth, teat and distal extremity, not itchy
Bluetongue- virus spread by insects, lesions on feet and a blue tongue
Punch biopsy and skin scraping - both work, but skin scraping is less infective
You need a very sensitive test if: 1. Disease is rare (ie: BSE), or 2. Early Dx improves prognosis (ie: HIV in people), or 3. The disease is highly lethal or consequences of missing a case are severe. (ie: Rabies, Brucellosis, BSE, Screw-worm, FMD, EIA)
Remember that a HIGHLY SENSITIVE test will have very FEW false negatives. That means if a test is highly sensitive, you can TRUST a NEGATIVE TEST. This sounds contradictory, but it makes more sense if you review this sensitivity diagram.
Sensitivity=a/(a+c). "a" are true positives. "c" are false negatives. If sensitivity is HIGH then "c" (FALSE negs) must be small. Therefore, high sensitivity means you can really trust a NEGATIVE result to be correct.
PVP is 84%. The trick with this kind of question is to pick an imaginary number of animals that you test, like 1000, and fill out your 2x2 table from there. Follow the links to see diagrams step by step.
If prev is 10% then there must be 100/1000 dogs with heartworm and 900 dogs that are disease-free.
A 96% sensitive test will correctly call 96/100 positive (box "a"), and IN-correctly call 4/100 negative, (box "c": these are the false negs).
If 100/1000 animals are infected, then 900/1000 are disease-free. Your 98% specific test will correctly call 882/900 disease-free (box "d": 0.98 X 900=882) and IN-correctly call 18/900 positive, (box "b": these are the false pos).
Now your a,b,c,d boxes are all filled, it is easy to calculate PVP=a/(a+b)=96/(96+18)=84%
Which three nerve blocks will correctly isolate the majority of equine lamenesses?
A - Heel, High 4-point, Proximal metacarpal
B - Suspensory ligament infiltration, Coffin, Proximal metacarpal
C - Low 4-point, Fetlock, Peroneal
D - Median/Ulnar, Low volar, Navicular bursa
E - Palmar digital, Abaxial sesamoid, Low palmar
This is the classic "Valentine heart" of feline Hypertrophic Cardiomyopathy (HCM).Note the very high RR and HR. Typically see HCM in cats 5-7 years old, more often in males.
Cause unknown. Look for thickened L. ventricle wall on echocardiography. Follow this link to see thickened L ventricle on necropsy
May see secondary pulmonary hypertension, edema, pleural effusion. DDX includes hyperthyroidism, systemic hypertension, acromegaly, congenital aortic stenosis.
Systolic murmur loudest on L betw 5th-6th suggests MITRAL valve insufficiency (left AV). Aortic insufficiency is DIASTOLIC. Tricuspid valve murmurs (right AV) are loudest on the RIGHT (See Blackwell's, p. 905, Tschauner p. 212 for excellent murmur DDX tables).
Taurine deficiency is associated with DILATED cardiomyopathy (DCM) in cats. Think more of LARGE BREED DOGS with DCM.
Technically, HCM is a form of congestive heart failure, but the "Valentine" radiograph points you to the much more specific diagnosis of HCM.
A stress leukogram is characterized by:
A - Neutropenia, lymphocytosis, eosinophilia
B - Neutrophilia, lymphocytosis, eosinopenia
C - Neutrophilia, lymphopenia, eosinophilia
D - Neutropenia, lymphopenia, eosinopenia
E - Neutrophilia, lymphopenia, eosinopenia
his is Trichomoniasis , caused by Trichomonas gallinae, and diagnosed by microscopic smear exam of the caseous oral exudates. Look for trichomonads. More a problem in PIGEONS, but can cause disease in chickens.
Remember Trichomonas foetus in cattle causes infertility (early embryonic death actually, 1st 2 months pregnancy). Infected bulls are mechanical carriers to cows.
Candidiasis is a fungal disease that can look SIMILAR to trichomonas in chickens. Follow this link to see a Merck image of Candidiasis.
Caused by Pasteurella multocida, Fowl Cholera causes sudden onset septicemia with VARIABLE signs. (Sudden death, anorexia, depression, mucoid beak discharge, ruffled feathers, diarrhea, increased RR.
Aspergillosis presents as respiratory disease. See fungi on microscopic smear, may see granulomatous lumps in lungs.
See sudden death with Necrotic enteritis, caused by Clostridium perfringens. Follow this link to see the so-called "Turkish towel" intestinal pseudomembrane of Necrotic enteritis.
This is Infectious Coryza.
Think acute respiratory disease with nasal discharge, sneezing, and SWELLING UNDER THE EYES. Caused by Avibacterium (Haemophilus) paragallinarum, infected flocks are a constant threat to uninfected flocks; farms with multiple-age flocks can perpetuate disease.
In the USA, "All-in/all-out" management has essentially eliminated infectious coryza from many commercial poultry farms. Follow this link to see original Merck image of Infectious Coryza.
Infectious Laryngotracheitis (ILT) look for gasping, coughing, blood stained beaks, blood occluding trachea on necropsy. A highly contagious herpesvirus infection, severe forms of ILT, can have 50% mortality. In most states ILT is REPORTABLE. Follow this link to see an image of ILT.
Infectious Bronchitis is characterized by respiratory signs, decreased egg production and poor egg quality. Classically may see "wrinkled eggs" with inf Bronchitis.
Pasteurella multocida causes Fowl Cholera. Think sudden onset septicemia. Signs vary greatly. In acute fowl cholera, dead birds are first indication of disease. May see fever, depression, anorexia, oral mucoid discharge, ruffled feathers, diarrhea, increased respiratory rate.
Follow this link to see an image of Fowl Cholera.
Another name for Candidiasis is thrush. Think Candida albicans, thickened mucosa, whitish, raised pseudomembranes in crop, mouth and esophagus. Follow this link to see an image of Candidiasis.
Encephalomyocarditis virus (EMCV) is caused by a cardiovirus in the family picornaviridae. Confusingly, the virus is named for its effects on mice.
Think of rodents and exotic zoo mammals with EMCV.
Pig-to-pig contact, contamination of swine feed and water by rodents or ingestion of dead rodents may cause disease. See pulmonary edema and copious transudate in the respiratory tract, causing cardiac failure.
Zoo outbreaks of EMCV have included lions, African elephants, rhinos, hippos, sloths, llamas, antelope and nonhuman primates. An outbreak of lion deaths at a Florida zoo in the USA occurred after feeding them the carcass of an African elephant that had died of EMCV.
Edema disease is a neurologic disease caused by a hemolytic Escherichia coli producing Shiga toxin e2 and F18 pili resulting in high mortality in recently-weaned pigs.
Glasser's Disease, caused by Hemophilus parasuis is usually an acute disease of 6 to 8 week-old pigs which causes fibrinous arthritis, polyserositis, and meningitis.
Porcine Reproductive and Respiratory Syndrome (PRRS), is an arterivirus causing reproductive failure and post-weaning respiratory disease.
Pseudorabies is a herpesvirus: infection causes CNS disease in neonates, respiratory disease in weaned pigs, and fever in all ages.
Which three diseases are on the differential diagnosis list when encountering sudden death in a young, fast-growing calf?
A - Lasalocid toxicity, Salmonellosis, Lymphosarcoma-juvenile form
B - Salmonellosis, Colibacillosis, Enzootic Calf Pneumonia
C - White muscle disease, Enterotoxemia, Colibacillosis
D - Bovine Viral Diarrhea, Lasalocid toxicity, White muscle disease
E - Winter dysentery, Enterotoxemia, IBR-encephalitic form
Senecio spp. (ragwort).
Common plants containing pyrrolizidine alkaloids (PA) are: Senecio vulgaris, S. jacobea, Amsinckia intermedius, Heliotropium europaeum, Crotolaria spectabilis.
Although generally not palatable, livestock will eat these plants when baled in hay or on pasture when forage is scarce. Chronic ingestion allows accumulation of toxic levels of PA, resulting in hepatic fibrosis.
Poisoning is most common in horses and cattle, sheep and goats are more resistant to toxic effects.
Persea spp. (avocado leaves) contain persin. Signs of toxicity are: noninfectious mastitis, abrupt cessation of milkflow, heart failure.
Nerium spp (oleander) contain cardiac glycosides. Signs of toxicity are: sudden death, weakness, diarrhea, cardiac arrhythmias.
Lupinus spp. (lupine) contain alkaloids. Signs of toxicity are: birth defects (ingestion at 40-70 days in cattle), abortion, tremors, incoordination, head pressing, seizures.
Astragalus and Oxytropis spp. (locoweed) contain alkaloids (swainsonine). Signs of toxicity are: excitability, incoordination, difficulty eating, exaggerated mouth movements, depression.
Bluetongue is almost exclusively a sheep disease, (but cattle and deer can get it).
Rinderpest mainly affects cattle and is reported to be eliminated as of October 2010 by the United Nation's Global Rinderpest Eradication Program. Because it is a classic severe and reportable vesicular disease, vets will likely need to keep rinderpest on their mental DDX list for years to come.
Pseudorabies is basically a pig pathogen. Can affect cows, but horses (and humans) are resistant
Vesicular Stomatitis (VS) can occur in horses, pigs, cows. Remember the big 8 vesicular diseases: BVD, IBR, BPS, MCF, Bluetongue, VS, FMD, Rinderpest)
Refs: Pasquini's Guide to Bovine Clinics, 4th ed. pp 8-11, 247, Pasquini's Guide to Equine Clinics, 3rd ed. pp. 289, 302 and the Merck Veterinary Manual online edition.
A 12-year old male neutered cat weighing 14 pounds is presented with a 2-month history of PU/PD, increased appetite, lameness, weight gain, exercise intolerance and dyspnea.
Physical exam shows a systolic heart murmur with a gallop rhythm, a lateral chest radiograph shows pulmonary effusion and a large heart.
A CBC shows
PCV=48 %.............[N=24-45%], WBC=14,850..[N=3800-19,500]
Neuts=88%............[N=35-75% ], Lymphs=4%..[N=20-55%]
Blood chemistry reveals the following
Total protein=10.1..[N=5.7-8.0], Glucose=350..[N=63-132]
Alk Phos=200.........[N=3-65], Cholesterol=250..[N=95-130]
BUN=47 mg/dL.......[N=10-30], Creatinine=3.4 mg/dL..[N=0.8-2.0 ]
U Sp. G= 1.018........[N=1.020-1.040]
Glucose +++, WBC ++, RBCs +, protein +++
Which one of the following choices is the most likely diagnosis?
A - Hyperthyroidism complicated by renal disease
B - Acromegaly
C - Pancreatic exocrine insufficiency
D - Hyperadrenocorticism
E - Diabetes insipidus complicated by cardiomyopathy
After 28 days. According to the Compendium for Rabies Control, a peak rabies virus antibody titer is reached 28 days after initial vaccination and immediately after booster vaccination.
Here are some thoughts on rabies:
When in doubt, it is never wrong to check with your local health department.
Basically all potential rabies exposures boil down to 2 questions:
1. Who is involved?
Animal-Animal exposure (less alarm bells)
Animal bites/exposes human (more alarm bells)
2. Was animal vaccinated/up to date on vaccination?
Up to date on vaccs (less alarm bells, shorter observation)
Vaccinated, but not up to date (Handle on case-by-case basis)
Un-vaccinated pet (more alarm bells, euthanize or long observation period)
Wild animal, esp. bats, raccoon, skunk (euthanize, send head to state lab)
When dealing with rabies questions, ask yourself if this seems like a HIGH-risk exposure (ie: wild raccoon bites a child)
or a LOWER risk exposure (ie: Up-to-date vaccinated dog messes with woodchuck but no bite wounds on dog).
For high risk lean towards euthanasia/testing or long quarantine. For low risk lean towards short observation period (10 days) and a rabies booster.
Signs of hepatic encephalopathy (ataxia, disorientation, vomiting, diarrhea) beginning after weaning combined with polyuria/polydipsia ("drink and pee alot") in a cryptorchid male Yorkshire terrier says Congenital Portosystemic Shunt.
Seen most in pure-breeds. Think SMALL Maltese, Yorkshire terrier, Min. Schnauzer. (But can see in Old English sheepdog, Irish Wolfhound)
Usually in YOUNG animals, especially after weaning. 50% of males are CRYPTORCHID.
Lead poisoning can cause vomiting, diarrhea and CNS signs (blind, hyperactive, seizures). Can see PU/PD in older animals but Hx here puts a shunt first on DDX.
This is the clinical picture of multiple cartilaginous exostosis (MCE-scroll down for details) also called osteochondroma, a benign proliferative disease of bone and cartilage typically seen in the metaphyseal region. Can be on any bone, including ribs, long bones, vertebrae (especially thoracic spinous processes).
See in YOUNG dogs, cats, horses, humans. Stops when growth plates close.
Often asymptomatic, but can see pain, lameness if compress overlying nerves, tendons. Can see neurological signs if compress spine.
Follow this link to see the original Merck image with explanatory text.
Do not confuse osteochondroma with OsteochonDROSIS (OC) or Osteochondrosis dissecans (OCD). Primarily a JOINT problem, (especially SHOULDER, stifle) in 4-10 month old rapidly-growing large breeds.
Hypertrophic pulmonary osteopathy is a paraneoplastic disease middle-aged-older dogs/cats, secondary to mass in thorax, abdomen- see swollen distal limbs.
Chondrosarcoma, Fibrosarcoma are older animal diseases typically > 6 years.
Horses with cauda equina neuritis (also called polyneuritis equi) have a progressive symetric LMN paresis of the tail, bladder, rectum, anal sphincter. Look for urinary incontinence, fecal retention and a weak or paralyzed tail. May see hind limb paresis if lumbosacral spinal cord is affected.
Cranial nerves can also be affected, but typically cranial involvement is asymetric. May see temporal or masseter atrophy (Cranial Nerve 5), facial paralysis and exposure keratitis (Cranial nerve 7), head tilt or other CNS signs.
Cause is unknown, may be an autoimmune process. Grave prognosis. Eventually euthanized.
Herpesvirus myeloencephalopathy (EHV-1) may also present with urinary incontinence, but this is an uncommon manifestation of equine rhinopneumonitis. You would expect to hear a history of the more common EHV signs in other horses from the same farm, like respiratory disease ("snots") in foals and abortions in mares.
It is 48%. The trick with this kind of question is to pick an imaginary number of animals that you test, like 1000, and fill out your 2x2 table from there. Follow the links to see diagrams step by step.
If prev is 5% then there must be 50/1000 cats with FeLV and 950 cats that are disease-free.
A 90% sensitive test will correctly call 45/50 positive (box "a"), and IN-correctly call 5/50 negative, (box "c": these are the false negs).
If 50/1000 animals are infected, then 950/1000 are disease-free. Your 95% specific test will correctly call 902/950 disease-free (box "d": 0.95 X 950=902) and IN-correctly call 48/950 positive, (box "b": these are the false pos).
Now your a,b,c,d boxes are all filled, it is easy to calculate PVP =a/(a+b)=45/(45+48)=48%
A poultry operation has experienced sudden die-off of 5% of its' birds. Another 10% are sick with cyanosis and edema of the head, comb, and wattle. Many have subcutaneous ecchymotic hemorrhages on the shanks, feet and head.
Some have a greenish diarrhea. On necropsy, petechial hemorrhages are visible on visceral organs and in muscles and there are blood-tinged oral and nasal discharges. A few birds that survived illness have developed torticollis, opisthotonos, and appear incoordinated.
What test is most appropriate to confirm the presumptive diagnosis?
A - Virus isolation from tracheal or cloacal swab
B - Hemagglutination test on acute plasma
C - Biopsy brain, spinal cord, proventriculus, gizzard
D - Bacterial culture and isolation from visceral lesions on 5% blood agar
E - Demonstration of toxin in serum, liver homogenates, or crop washings
Newborn calves with arthrogryposis ("crooked calf") have ankylosed, rigid limbs, scoliosis, kyphosis, and sometimes a cleft palate.
The most common toxic cause of arthrogryposis in the calf or lamb is consumption of toxic alkaloids (anagyrine) in Lupine spp plants by pregnant dams. Click here to see a Lupine plant.
Adults that eat lupine may display inappetence, dyspnea, convulsions or death from respiratory paralysis. If lupines become infected with a fungus (Phomopsis leptostromiformis), mycotoxic lupinosis can cause hepatic damage.
Infectious causes of congenital arthrogryposis include in-utero infection with Bluetongue virus or Akabane virus.
Sorghum (Sudan grass, Johnson grass, Milo) can cause a neurologic toxicity, primarily in horses, or cyanide toxicity.
Wide marginal excision. Think of mast cell tumors when you see round cells with intracytoplasmic granules on a fine-needle aspirate. Follow this link to see mast cell cytology.
Wide marginal surgical excision offers the best chance for a cure of mast cell tumors especially if the cell type is well differentiated, if margins are clear and there is no evidence of spread to local lymph nodes.
The location of the mass on the lateral hock is a challenge in this case, because it may not be possible to make wide and deep margins without skin grafts or healing by second intention.
Benign neglect is a good treatment option for masses confirmed on cytology to be cutaneous histiocytoma (pleomorphic round cells with clear blue cytoplasm-no granules).
Histiocytomas are benign and usually resolve on their own within three months.
Doxycycline is an antibiotic often used to treat tick-borne diseases. In acute Ehrlichia canis infections, light blue intracytoplasmic inclusion bodies, morulae, may rarely be found within peripheral white blood cells.
Itraconazole is an antifungal drug used treat infections such as Aspergillosis, Cryptococcus, blastomycosis, histoplasmosis and coccidioidomycosis.
In these cases, cytology would demonstrate dark staining fungal elements (hyphae, sperules, etc) extracellularly, and these elements would be much larger than the cells themselves.
Which choice lists these species in order of gestation length, from longest to shortest pregnancy?
A - Cow, Horse, Pig, Dog, Goat
B - Cow, Horse, Pig, Goat, Dog
C - Llama, Pig, Sheep, Ferret, Cat
D - Horse, Cow, Goat, Pig, Dog
Here is a list of gestation length for the major species, in order: Llama 1 year (350d), Horse 11 mo (330d), Cow 9 mo (~280 d, same as PEOPLE), Sheep/goats 5 mo (150d), Pig 4 mo (114d), Dog/ Cat 2 mo (60d), Ferret 1.5 mo (42d.).
Basic questions on estrus cycle and gestation come up over and over, so commit them to memory for the major species at LEAST (Cow, Horse, Dog, Cat, Sheep/Goat, Pig). Merck has two excellent tables:
In general, the BIGGER the beast, the LONGER the gestation ie: Mice are about 20 days, elephants are TWO YEARS (660 days)!
This is copper deficiency, which presents with "Ain't Doin' Right" ( ADR ) signs : ACHROMOTRICHIA (depigmented hair, especially around the eyes= "SPECTACLES") rough coat, decreased milk yield, lameness and decreased fertility, libido and "Peat Scours" also called "Teart" (severe scours with gas bubbles).
Molybdenum toxicosis causes a secondary DEFICIENCY in Copper.
Oak poisoning is more a gradual, multisystemic disease (nephrotoxic, hepatotoxic), can see PU/PD, hematuria, weight loss.
Tetany is the classic presentation of Hypomagnesemia in cattle, along with hyperexcitability, ataxia, convulsions and death.
Selenium toxicosis has many presentations depending on species, dose and length of time exposed.
This is an aortic thromboembolism, secondary to feline hypertrophic cardiomyopathy (HCM) the most common heart disease of cats.
Physical signs of aortic thromboembolism include hindlimb paresis or paralysis, cyanotic nail beds, toe pads and cold extremities, decreased or absent pulses, contracted and painful hindlimb muscles, relentless crying.
Don't confuse this presentation with the nonpainful plantigrade stance of diabetic neuropathy in cats, an uncommon sequella of diabete mellitus.
Often, cats with HCM are asymptomatic and the problem is discovered on physical exam, with auscultation of a systolic murmur, evident in 80% of cats with HCM. Physical signs in cats with clinical HCM may include tachypnea, dyspnea, anorexia, vomiting and lethargy
Whipworms, (Trichuris spp) are typically found in the cecum and large intestine. Mainly in dogs, rare in cats. Trichuris suis in pigs can cause unthriftiness in younger animals.
If clinical, look for signs of large bowel diarrhea (frequent urgent defecation of loose watery feces, possibly with mucus or fresh blood). Can be associated with a hypoadrenocorticism-like syndrome (hyponatremia, hyperkalemia, azotemia, metabolic acidosis).
Whipworm infection has been suggested as one cause of cecocolic intussusception.
Physaloptera spp (Stomach worms) may cause vomiting, anorexia, dark feces.
Spirocerca lupi makes nodules in the esophageal, gastric, or aortic walls. Typically asymptomatic.
Roundworms (Toxocara canis) may cause visceral and ocular larva migrans.
Hookworms (Ancylostoma spp) may cause cutaneous larva migrans.
This is one of the 5 classic "anemia / edema " presentations of horses. (Remember "Big 3 are PEE" Purpura, EIA, EVA; 2 minors are Babesia, ehrlichia (now renamed Anaplasma).
Inclusion bodies in the neutrophils of a California horse with icterus and petechiae and an undulating fever says Equine granulocytic ehrlichiosis (EGE).
Originally classified as Ehrlichia equi, but is NOW called ANAPLASMA phagocytophila due to DNA sequencing studies. EGE is a seasonal necrotizing vasculitis (edema, icterus, petechiae) seen in N. California, suspected to be tick borne.
See dependent edema with Equine viral arteritis (EVA), but also should see respiratory presentation (conjunctivitis/pinkeye, rhinitis) +/- abortions.
Equine infectious anemia (EIA) is rarely seen today because of testing programs, but could present this way. Less likely because 92% cases seen around the Gulf of Mexico states (Texas to Florida), Mississippi river valley AND no inclusion bodies.
Purpura hemorrhagica is a type III Antigen/Antibody/Complement complex disease causing vascultis, petechia, purplish discoloration, usually afebrile, with Hx of recent Strangles (Strep equi equi) or bacterin vaccination.
Equine Babesiosis presents more as a hemolytic anemia: seen in the S. USA, endemic in Southern FLORIDA