2023: May Flashcards
A flock from a turkey farm is presented with a mysterious illness. Several dead birds are notable, mostly younger animals.
Sick turkeys are listless, with drooping wings, unkempt feathers, yellow droppings. Sick older birds are emaciated.
Necropsy shows a yellowish green, caseous exudate in the ceca, cecal ulcerations, and thickening of the cecal wall. A typical liver looks like the image below.
What is the diagnosis?
(look for photo on email for may 1st 2023)
A - Necrotic enteritis
B - Hemorrhagic enteritis of turkeys
C - Avian spirochetosis
D - Histomoniasis
E - Coronaviral enteritis of turkeys
D - Histomoniasis
This is histomoniasis, the combination of characteristic “bull’s-eye” lesions on liver and cecal changes are pathognomonic. Caused by protozoan Histomonas meleagridis, transmitted in eggs of cecal nematode Heterakis gallinarum. Expect a depression/diarrhea presentation.
Expect to see more sudden death with necrotic enteritis caused by Clostridium perfringens.
Signs of avian spirochetosis are highly variable, may be absent: see listlessness, shivering, increased thirst, green yellow diarrhea with increased rates early on. Caused by a tick-borne Borrelia. Look for characteristic enlarged, mottled spleen with petechial hemorrhages, similar to Marble spleen disease of pheasants.
Expect depression, bloody droppings, substantial mortality with hemorrhagic enteritis of turkeys.
Expect diarrheal presentation with coronaviral enteritis of turkeys but NOT the characteristic cecal/liver lesions described on necropsy above.
An eight-month-old male intact German shepherd dog is presented for poor weight gain, chronic diarrhea, and polyphagia.
Fasting serum trypsin-like immunoreactivity (TLI) measurement is <2.0 µgL (Normal = 5.7-45.2 µg/L).
What is the most likely cause of this dog’s clinical signs?
A - Acute pancreatitis
B - Inflammatory bowel disease
C - Acinar cell atrophy
D - Pituitary dwarfism
E - Small intestinal bacterial overgrowth
C. Acinar atrophy
This dog has exocrine pancreatic insufficency (EPI) due to pancreatic acinar atrophy (PAA). PAA is the most common cause of EPI in GErman shepherd dogs and is considered hereditary. It is also seen in rough-coated collies and eurasians.
In cats and older dogs EPI is most commonly caused by chronic panreatitis.
Serum TLI is the best test for EPI in dogs and cats. A significatly low (<2.5 mg/L) fasting TLI is diagnostic for EPI.
In EPI there is impared synthesis and release of digestive enzymes by pancreatic acinar cells, resulting in maldigestion, weight loss/failure to gain weight, diarrhea, and polyphagia. Concirrent small intestinal dysbiosis and cobalamin deficiency are common.
TReat with oral enzyme replacement and cobalamin supplementation if deficient. Patients with EPI require life-long enzyme replacement. Prognosis is good with appropriate treatment.
Retained placenta and metritis can predispose to which one of the following secondary conditions in horses?
A - Cystic endometriosis
B - Colic
C - Postpartum dysgalactia syndrome
D - Laminitis
E - Contagious equine metritis
In horses, retained placenta and septic metritis can lead to acute laminitis.
There are four main types of laminitis:
sepsis/SIRS related (following septic metritis, pleuropneumonia, colitis, grain overload, etc.; in research they induce this with black walnut (Juglans nigra) or carbohydrate overload)
endocrinopathic (horses with insulin dysregulation/equine metabolic syndrome or equine Cushing’s disease; also associated with lush spring grasses)
traumatic (aka “road founder”)
support-limb (eg severe lameness on one limb requiring over-dependency on opposite leg, which then develops laminitis)
Under what conditions is a very sensitive test used?
A - Rare disease; early diagnosis improves prognosis
B - Common disease; infectious diseases
C - Treatment does not affect prognosis; non-infectious diseases
D - Lethal disease; highly prevalent disease
E - Zoonoses; untreatable diseases
You need a very sensitive test if:
- Disease is rare (eg:BSE)
- Early Dx improves prognosis (eg: HIV in people)
- The disease is higly lethal or consequences of missing a case are severe (eg: rabies, brucellosis, BSE, screw-worm, FMD, EIA)
Remember that a HIGHLY SENESTIVTIVE test will have very FEW false negatives.
That means if a test is highly senesitive, you can TRUST a NEGATIVE TEST.
Sensitivity=a/(a+), “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 NEGATIVE result to be correct.
For the last ten years, your state has had a mandatory vaccination program against “pedunculated giblet disease” in fur-bearing turtles and the prevalence of this terrible disease has decreased markedly.
How does this decrease in prevalence affect the predictive value positive (PVP) of the best serologic test for pedunculated giblet disease?
A - PVP increases as prevalence decreases
B - PVP decreases as prevalence decreases
C - PVP stays the same as prevalence decreases
D - PVP is affected by specificity, not prevalence
E - PVP depends on the number tested, not prevalence
B - PVP decreases as prevalence decreases
Don’t overthink this: As prevelane of a disease goes DOWN, PVP of your serologic test also goes DOWN.
That is, as your disease becomes more and more rare, the predicitve value of your samel old test gets WORSE.
From which animal was this blood sample collected?
What do certain species blood look like?
A - Camelids
B - Psittacines
C - Ferrets
D - Reptiles
E - Chinchillas
A - Camelids
Camelids (llamas, camels, alpacas) normally have ellipsoid red blood cells (RBCs) which lack central pallor.
Birds and reptiles have nucleated, elliptical RBCs.
may 8 2023 NAVLE
A four-month-old filly is presented with a four-day history of lethargy, heavy breathing, cough and decreased appetite.
Value, Normal
104.9°F (40.5°C), 99.0–100.6°F (37.2–38.1°C)
HR=72 bpm, 28-40 bpm
R=44 brpm, 10-14 brpm
On lung auscultation asymmetrically-distributed crackles and wheezes are audible. Some areas have no breath sounds and a dull resonance on thoracic percussion. A lateral chest radiograph shows consolidated nodular lung lesions and mediastinal lymphadenopathy.
Pneumonia due to Rhodococcus equi infection is confirmed based on culture and polymerase chain reaction results on a transtracheal wash.
Which one of following choices is the most appropriate treatment?
A - Chloramphenicol and aminophylline
B - Clarithromycin and rifampin
C - Tilmicosin
D - Procaine penicillin G and gentamicin
E - Vancomycin and atropine (if bronchospasm is observed)
B - Clarithromycin and rifampin
Start this filly on clarithromycin and rifampin.
In this case, a chest radiograph with consolidated nodular lung lesions and mediastinal lymphadenopathy is highly suggestive of Rhodococcus equi in a foal under five months of age.
Polyarthritis, polysynovitis, and diarrhea can also be seen in affected foals.
Combination treatment of rifampin combined with either erythromycin, clarithromycin, or azithromycin is appropriate to treat R. equi pneumonia.
However, in one retrospective study, the combination of clarithromycin and rifampin was shown to be the most effective of the three.
Tilmicosin, while a macrolide, is not very active against R. equi and swelling can occur at injection sites in foals; it is not recommended for treatment of R. equi pneumonia.
A two-year-old beagle is presented with patchy alopecia, papules, and thick crusts, on the ventral abdomen, chest, ears, and elbows.
The owner reports intense pruritus and a positive pinnal-pedal reflex is observed.
A flea comb does not reveal any fleas.
The image below shows what was discovered from a skin scraping.
Which one of the following organisms is depicted in the image?
may 10 email
A - Neotrombicula autumnalis
B - Straelensia cynotis
C - Demodex canis
D - Sarcoptes scabei
E - Cheyletiella yasguri
D - Sarcoptes scabei
This is sarcoptes scabei, a highly contagious mite.
A postiive pinnal-pedal reflex (scratching action with the dog’s hind limb when the examiner fmlyrubs the edge of the dog’s pinna between thumb and forefinger) is seen in 82% of dogs with sarcoptic mange but observed in only 7% of dogs with pruritus caused by other diseases.
Cheyletiellosis (walking dandruff) is another highly contagious mite. Unlike sarcoptes, they have very prominent mouthparts.
A nine-year-old Quarterhorse mare is presented with a right hind limb lameness.
She tends to drag the right toe, and has a stabbing gait in that limb (adducts hindlimb, then suddenly abducts it just before the hoof hits the ground).
Hock flexion of the right hind significantly exacerbates the lameness for 5-6 strides. A radiograph of the hock is taken, shown below.
What is the common name for this problem?
may 11, 2023 email for photo
A - Tarsal hydrarthrosis
B - Osselets
C - Ringbone
D - Splints
E - Bone spavin
E - Bone spavin
This is bone spavin, an osteoarthritis/degenerative joint disease of the distal hock joints, usually affecting the distal intertarsal and tarsometatarsal articulations. The number one hock problem (tarsus) in horse.
If the horse is lame due to bone spavin, it tends to drag toe or have “stabbing” gait in the affect hindlimb. Occaisionally, you may see thickening of the soft tisses over distal hock joints. The problem cab be unilateral or bilateral with various degrees of lameness.
Typical Tx: intro-articular steroids and hyaluronic acid, phenylbutazone as needed, continue with work. Over time, distal hock joints are likley to anylose (fuse) on their own and lameness ends. Additional treatements include shockwave, biophosphanates, alcohol arthrodesis, cunean tenectomy or neurectomy.
Tarsal hydrarthrosis (bog spavin) is a chronic synovitis of tarsocrural joint -look for swelling and distention of the joint capsule.
Cytological evaluation of a blood smear from a sick horse reveals the following (see below).
Which constellation of signs would you expect in a typical acute case of a horse with this disease?
photo on email from may 12, 2023
A - Nystagmus, head tilt, strabismus
B - Weight loss, partial anorexia, poor performance
C - Elevated serum liver enzymes, hyperammonemia, head-pressing
D - Limb edema, ventricular arrhythmias, ataxia
E - Fever, petechiations, hemolytic anemia
E - Fever, petechiations, hemolytic anemia
This cytology shows Babesia caballi, one of the causative agents of equine piroplasmosis (the other is Theileria equi - looks like maltese cross under the microscope) and acute disease is characterized by fever, petechiations, and signs consistent with hemolytic anemia.
Piroplasmosis is characterized by hemolytic anemia and is spread primarily by ixodid ticks or blood contamination. It is endemic in tropical, subtropical, and some temperate regions.
It is REPORTABLE in the USA.
Clinical infectn can be acute, chronic, or inapparent depending on strain, the horse’s health, and geographic region.
Acute clinical signs include those described here along with lethargy, anorexia, pale or icteric mucous membranes, and with the worsening disease, tachycardia, tachypnea, weakness, and hemoglobinuria. Weight loss, poor prformance, and partial anorexia can be seen along with mild anemia in horses with chronic piroplasmosis.
Dx: Demonstrate intra-erythrocytic organisms on blood smear and/or serology.
Rx: Imidocarb diproprionate and supportive care. There is a different duration of Tx depending on whether in edemic or nonendemic region (becasue trying to treat clincical signs in endemic region vs. clear disease in nondemic region).
Limb edema, ventricular arrhythmias, and ataxia (the latter two uncommonly) can be seen with Anaplasma phagocytophila infections in horses, along with fever, petechiations, icterus, and depression.
A finishing farm has pigs that are about 12 weeks old. The farmer is noticing that about 10% of the pigs are failing to thrive, have a yellow watery diarrhea, are becoming emaciated, and dying - even if treated with antibiotics.
Affected pigs are pale to icteric. Examination reveals enlarged inguinal lymph nodes. What is the causative agent?
A - Herpesvirus
B - Manangle virus
C - Parvovirus
D - Paramyxovirus
E - Circovirus
E - Circovirus
Porcine circoirus 2 (PCV2) is a nonenveloped DNA virus first described in Canada in 1991 that is ubiquitous today worldwide. It causes postweaning multisystemic wasting syndrome (PMWS) as it attacks the immune system. It is preventable with vaccination.
The virus is also associated with porcine dermatitis and nephropathy syndrome casued by necrotizing vasculitis, which is mre prominent in the skin, renal pelvis, mesentery, and spleen.
A client presents a 25-pound dog (11.4 kg) who was just observed swallowing a bottle cap.
Which one of the following choices would be the safest approach for this dog.
A - Remove via gastrotomy
B - Administer silicon coated magnet to keep it in stomach until dissolution
C - Remove via endoscopy
D - Administer a proton pump inhibitor to stimulate gastric acid secretion
E - Administer motility modifiers to encourage passage
C - Remove via endoscopy
Endoscopy would be the safest route of removal in this case. The cap is large enough to be lodged in the intestinal tract if allowed to pass.
With endoscopy, you can get it out gently and quickly with minimal anethesia and no suturing. This is preferable to gastrotomy which would require incicsions in both the abdominal wall and the stomach.
may 17, 2023 email
A canine vaginal smear is shown below.
At what stage of the estrous cycle is this dog?
(what are the stages of the estrous cycle?)
A - Diestrus
B - Anestrus
C - Proestrus
D - Cannot tell from this slide
E - Estrus
E - Estrus
This dog is in estrus. Look for >90% cornified superficial cells (angular, sharp edges like cornflakes, tiny pyknotic nuclei or no nuclei) and no neutrophils.
In contrast, during diestrus, vaginal smears have >50% nucleated, round-edges parabasal cells. Look for the reappearance of neutrophils (variable numbers)
Full cornifocation usually coincides with receptivity. Use serial serum progesterone monitoring with vaginal cytology to predict the LH surge and help estimate ovulation.
The initial progesterone rise is considered day 0, breed twice during days 3-6 for maximal breeding success.
