Week 4 - March 3 Day 4 Flashcards
Topic: Canine GDV
- What imaging procedure, and what position, would you use to confirm a diagnosis of GDV? Explain why
- Abdominal radiograph, right lateral recumbency. Why?
A typical GDV occurs with repositioning of the pylorus to the left dorsal abdomen. A right lateral radiographic image is the best position for revealing a gas filled left dorsally-displaced pylorus with a gas-filled ventral fundus separated by a soft tissue band (compartmented stomach). Although the features of a malpositioned stomach may be observed on the other radiographic views, they are often more difficult to interpret than that represented by the right lateral recumbency view. The severe amount of gas within the GI tract that is associated with GDV would make ultrasound exam interpretation extremely difficult at best.
Phenothiazines cause _________, but do not provide _________. One side effect is __________. They may decrease hematocrit due to splenic sequestration of red blood cells. They decrease the sensitivity of the myocardium to catecholamine-induced arrhythmias.
Phenothiazines cause sedation, but do not provide analgesia. One side effect is hypotension.They may decrease hematocrit due to splenic sequestration of red blood cells. They decrease the sensitivity of the myocardium to catecholamine-induced arrhythmias.
Alpha 2 agonists are ____________-____________. Effects of the drugs include an initial ___________ with _________ bradycardia and _____________ to follow. Respiratory ___________ and _________ (particularly in cats) are other side effects.
Alpha 2 agonists are sedative-analgesics. Effects of the drugs include an initial hypertension with reflex bradycardia and hypotension to follow. Respiratory depression and emesis (particularly in cats) are other side effects.
Topic: Canine Hypoadrenocorticism
Poodles are the poster children for Addison’s disease. Addison’s is a tricky disease to diagnose if you are not looking for it. It is also called “the great imitator” as it can look like renal failure, Gl disease, or acute collapse. The key signs in this case are the poodle in shock after a stressful event (owners were out of town), low heartbeat with cardiovascular collapse, a lack of stress leukogram in what should clearly be a stressed animal (normal white blood cell count in collapsed shocky patient), and Na:K ratio of less then 30 (hallmark for Addison’s), and a USG of less than 1.030.
Addison’s disease is due to lack of endogenous steroid and mineralocorticoid production. Endogenous cortisol is needed by every body system for proper function, and higher glucocorticoids as seen in stressed patients typically leads to a stress leukogram. Mineralocorticoid deficiency leads to the inability of the kidneys to retain sodium and secrete potassium. Remember, “water follows salt”, which leads to hypotonic dehydration due to excessive sodium losses.
Any emergency with acute cardiovascular collapse should immediately be treated with IV boluses of fluids and should not wait while you perform your diagnostics. Once your tentative diagnosis has been found, supplementing with IV dexamethasone will help restore steroids to the patient while you await for an ACTH stimulation test to confirm your diagnosis. Dexamethasone is considered the glucocorticoid of choice with suspected Addison’s, as it will not interfere with confirmatory testing.
This poodle responded within an hour to IV dexamethasone; he was up and alert and responsive. Cortisol levels pre- and post- ACTH gel administration were both low.
Addison’s is a life long disease that is managed with glucocorticoids (typically prednisone after diagnosis and mineralocorticoids.
Topic: Exocrine Pancreatic Insufficiency
- What is the most common cause of EPI in dogs? Explain.
- What is the most common cause of EPI in cats? Explain.
- What concurrent condition do cats typically have coupled with EPI?
- Pancreatic acinar atrophy is the most common cause of EPI in dogs. This is an idiopathic condition where the exocrine cells of the pancreas atrophy with minimal inflammation.
- Chronic pancreatitis is a much more common cause of EPl in cats than dogs. For this reason, dogs with EPI do not usually have concurrent diabetes mellitus because the endocrine cells are spared, whereas cats often do have concurrent DM. Neoplasia and infection are rare causes of EPI.
A 6-year old female spayed English Pointer presents for lethargy and weight gain. The owner notes that the dog is eating and drinking a normal amount, but the dog is still gaining weight. A physical exam reveals weak pelvic limbs, facial nerve paralysis, a symmetrically patchy haircoat, and seborrhea. Lab work reveals a normocytic, normochromic anemia with a PCV of 29% (35-57%), lipemic serum, and cholesterol of 1090 mg/dl
(135-278 mg/dl). What is the most likely diagnosis?
The correct answer is hypothyroidism. The clinical signs, physical exam findings, and lab work abnormalities are classical for hypothyroidism. Other common abnormalities seen with hypothyroidism include pyoderma, neuromuscular signs (ataxia, knuckling, vestibular signs, etc), markedly elevated triglycerides, and a mild normocytic, normochromic anemia. Hyperthyroidism rarely occurs in dogs. You would expect to see polyuria, polydipsia, and polyphagia with hyperadrenocorticism.
Topic: Feline Repro
Estrus in cats, defined as the behavioral receptivity to mating, typically lasts about _____ ________ (usually between _____-____ _________)
Interestrus, the period between one estrus and the next, has a variable duration of ?
Cats are ___________ ovulators. If a queen ovulates but does not become pregnant, a ______________ occurs and __________ ________ develop and secrete ____________. This inhibits ______ release from the hypothalamus and secretion of _____ and _______ from the anterior pituitary, preventing return to estrus (typically for ?. Additional clinical signs of pseudopregnancy are rare in cats.
Estrus in cats, defined as the behavioral receptivity to mating, typically lasts about 7 days (usually between 4-10 days)
Interestrus, the period between one estrus and the next, has a variable duration of 7-21 days.
Cats are induced ovulators. If a queen ovulates but does not become pregnant, a psuedopregnancy occurs and corpora lutea develop and secrete progesterone. This inhibits GRH release from the hypothalamus and secretion of LH and FSH from the anterior pituitary, preventing return to estrus (typically for 45-50 days). Additional clinical signs of pseudopregnancy are rare in cats.
What is the permanent dental formula for a cat?
A. 2(13/3 C1/1 P2/3 M1/3)
B. 2(13/3 C1/1 P3/2 M1/1)
C. 2(13/3 C1/1 P3/3 M1/3)
D. 2(13/3 C1/1 P4/4 M2/3)
The correct answer is 2(13/3 C1/1 P3/2 M1/1).
The most common cause of bacterial conjunctivitis in feline patients is Chlamydophila felis. This disease cannot be distinguished from
feline Herpesvirus-1 based on clinical appearance alone. Frequently, feline patients with these symptoms are infected with both of these
diseases simultaneously. Diagnosis of Chlamydophila felis is made by visualizing typical elementary bodies in the cytoplasm of
conjunctival epithelial cells or obtaining a positive fluorescent antibody (FA) test on a conjunctival scraping. The treatment of
Chlamydophila felis is topical tetracycline QID for one week post resolution of clinical signs.
Which is not a common cause of gastric ulcers in dogs and cats?
A. NSAIDS
B. Corticosteroids
C. Renal Failure
D. Opioids
E. Liver Failure
The answer is opioids. NSAIDS and corticosteroids compromise the mucus-bicarbonate protection of the stomach. Renal disease and the corresponding uremia cause decreased mucosal blood flow and gastric hypersecretion. Liver disease causes gastric ulcers by decreasing mucosal blood flow secondary to portal hypertension and thrombosis. Liver failure is also associated with increased histamine and gastrin levels leading to gastric hypersecretion.
You are treating Molly, an 8-year old feline, for hyperthyroidism. She is currently on methimazole 2.5 mg orally every 12 hours. Her labwork, including renal values, have been stable since diagnosis 2 months ago and her thyroid level is under control. The only concern is that Molly is experiencing extreme facial pruritis leading to excoriations. You believe this is due to a side effect of the medication. What other treatment option would be the best therapy for Molly?
A. Thyroidectomy
B. Tapazole
C. Imidocare
D. Levothyrexine
E. 1-31 therapy
The treatment of choice for hyperthyroidism in a case such as this would be radioactive iodine, or I-131 therapy. Molly would be a good candidate for this procedure since her renal values have remained stable while on methimazole.
Thyroidectomy can be performed, but many times some thyroid tissue is left behind or there is ectopic thyroid tissue, which
A 3-year old male domestic shorthair cat presents for a two day history of lethargy, vomiting and vocalizing progressing to recumbency. On initial evaluation, heart rate is 100 bpm, pulse quality is poor, mentation is obtunded, and there is a large firm bladder on abdominal palpation An intravenous catheter is placed. Which of the following is the most immediately life-saving intervention?
A. IV administration of a balanced electrolyte solution
B. IV administration of dextrose
C. IV administration of calcium gluconate
D. IV administration of sodium bicarbonate
E. Placing a urinary catheter to relieve urethral obstruction
F. IV administration of regular insulin
Calcium gluconate will serve to immediately counter the effects of hyperkalemia-induced bradycardia and cardiovascular collapse in this cat with a most-likely diagnosis of urethral obstruction. The other interventions will help to reduce the level of potassium and could be a part of therapy but may not take effect rapidly enough to address the most life-threatening component of the cat’s illness.
A 3-year-old male intact cat presents with a progressive history of coughing for the past 3 months. The cat lives indoors and outdoors and is not on any medications. Blood work shows a moderately elevated neutrophil count with a mild lymphopenia. Chest radiographs demonstrate a moderate bronchointerstitial pattern. The owners consented to a laryngeal exam, bronchoscopy, and a transtracheal wash. The image below is from the transtracheal wash. What is this organism and what is the treatment for it?
Spirocerca lupi and ivermectin
Strongylus endentatus and fenbendazole
Toxocara cati and fenbendazole
Aelurstrongylus abstrusus and ivermectin
The feline lungworm in cats is Aelurostrongylus abstrusus. Treatment with ivermectin and fenbendazole have been reported to be
Toxocara cati is a roundworm (ascarid) in which cats become infected by ingesting larvated eggs. The life cycle is complicated and involves migration through the liver and lungs. Eventually the larvae come up the mucociliary apparatus and are then swallowed where they develop in the small intestine. Eggs can readily be found in the feces, while adults can be visualized within the small intestine. Clinical signs in the kittens include poor body condition and a pot-bellied appearance. Vomiting may also be present. Diagnosis is best made via a fecal flotation and a transtracheal wash is unlikely to be as rewarding. Treatment options include selemectin, fenbendazole, pyrantel pamoate, milbemycine oxime, and moxidectin. It has been recommended that all kittens be dewormed beginning at 2 weeks of age until they are approximately 8 weeks old, at which point they should be transitioned to a heartworm preventative that is also effective against ascarids.
Strongylus edentatus is one of the large strongyles of horses found in the large intestines. Treatment includes ivermectin, moxidectin, pyrantel, and fenbendazole.
Spirocerca lupi is an esophageal worm found in dogs. They are found in the esophageal, aortic, and gastric walls of dogs that have eaten infected dung beetles, chickens, reptiles, or rodents. Chronic infection may cause neoplastic transformation of the surrounding tissues into sarcomas or rupture and life-threatening hemorrhage of the aorta. Treatment is with ivermectin or doramectin.
A one-month old foal develops fever, icterus, and diarrhea acutely. Bloodwork shows hyperfibrinogenemia, hypoglycemia, and elevated liver enzymes. Which of these conditions is most likely?
A. Herpesvirat hepatitis
B. Tyzzer’s disease
C. Clostridium novyi type B
D. Theiler’s disease
The correct answer is Tyzzer’s disease. This is the most likely cause because of the age of the foal and the acute nature of the disease.
Tyzzer’s disease is caused by Clostridium piliformis, which causes an acute necrotizing hepatitis. It affects only foals from about 1-6 weeks
of age. Theiler’s disease is a condition of adult horses. Clostridium novyi is rare in horses and seen much more in sheep and cattle.
Herpesvirus can cause hepatitis but is usually seen at or very soon after birth.
Which of these findings are most consistent with a diagnosis of chronic obstructive pulmonary disease in the horse?
A. End inspiratory wheezes
B. End inspiratory cracktes
C. End expiratory wheezes
D. Early expiratory wheezes
E. Early inspiratory wheezes
The correct answer is end expiratory wheezes. In chronic obstructive pulmonary disease (COPD), airway diameter is reduced by inflammatory exudate, edema, and bronchoconstriction. As lung volume decreases during expiration, the narrowed bronchioles collapse shut (dynamic airway collapse). This traps air distal to the closure and creates the wheezes heard as the airways narrow towards the end of expiration.
In addition to a routine pre-purchase exam of a 12 year old Thoroughbred mare, an ECG was performed which showed an increase in the P-R interval followed by occasional P waves that are not followed by a QRS-T complex. What does the owner need to know about this finding?
A. This horse is predisposed to developing an electrical-mechanical disassociation and needs further diagnostics before purchasing
B. This mare most likely has a ventricular septal defect and should not be purchased.
C. This is a first-degree atrioventricular block and should be treated immediately with quinidine.
D. This is a second-degree atrioventricular block, which is commonly seen in athletic horses.
The correct answer is this is a second-degree atrioventricular block, which is commonly seen in athletic horses. First-degree and second-degree blocks are considered variations of normal in the horse and are usually associated with high vagal tone. They are not predisposed to electrical-mechanical disassociation. An electrical rhythm is an ineffective method in trying to determine if there is a ventricular septal defect. If such a defect is suspected, the best way to evaluate the horse is by performing a cardiac ultrasound.
You are examining a 13-year old Paint mare for a 2-week history of inappetence and mild weight loss. On closer examination, you observe the following lesions on the white areas of the horse (see image). What condition should you consider?
A. Dermatitis secondary to renal failure
B. Photosensitization secondary to hepatic disease
C. Dermal necrosis secondary to NSAID administration
D. Primary insect hypersensitivity
Horses may demonstrate photosensitization from liver disease because the chlorophyll in the diet is usually converted to phylloerythin and excreted by the liver. With hepatic disease, the phylloerythin is deposited in the skin; UV light reacts with it and results in dermal damage. Skin lesions are not seen with NSAIDs and renal disease, whereas insect hypersensitivity is usually associated with urticaria.
A 24-year old Appaloosa has an increased heart rate, increased respiratory rate, and is pacing while staring at her abdomen. During initial colic work up there was no gastric reflux. On rectal exam, a distended large colon could be palpated. On abdominal ultrasound, large colon was the predominant structure visualized on the left side while the left kidney could not be visualized via ultrasonography. What is the most likely diagnosis?
A. Sand impaction
B. Strangulating lipoma
C. Right dorsal displacement
D. Nephrosplenic entrapment
The correct answer is nephrosplenic entrapment. The kidney is obscured as a result of a left dorsal displacement of the large colon over the nephrosplenic ligament. Additionally, the spleen is pushed away from the body wall, making it difficult to see on ultrasound. Large horses may be predisposed to this. Besides surgical correction, one may try to roll the horse 360 degrees. Pain associated with these types of displacements are usually mild to moderate.
Which of these control measures would be least effective for reducing Culicoides hypersensitivity in horses?
Insect repellents
A. Antitistamines
B. Pyrethrins
C. Placement of ceiling fans
D. Corticosteroid therapy
E. Insect repellants
The correct answer is antihistamines. In general, antihistamines are ineffective at reducing clinical signs associated with cutaneous hypersensitivity diseases in horses. The most important aspect of therapy is reduction of insect exposure. This can be achieved by moving horses away from breeding habitats, frequent bathing, and application of insect repellents. Corticosteroid therapy is required for management of many horses. Short acting corticosteroids should be used first.
A 3-year old Thoroughbred presents for evaluation after pulling up late in a recent race. You perform an ECG, which is shown below. What is the rhythm?
A. Atial fibilaion
B. Atrial tachycardia
C. Ventricular tachycardia
D. Normal sinus rhythm
E. Ventricular premature complexes
The correct answer is atrial fibrillation. The baseline shows coarse fibrillatory waves and the rhythm is irregular. For a base-apex lead in the horse, the deep S waves of the QRS complexes are normal. The other answers are incorrect because of the presence of flutter/fibrillatory waves and irregularity of the rhythm.
Which of the following stallions should definitely not be used for breeding?
A. A stallion with a previous infection with coital exanthema
B. stallion with 180 degree rotation of the testicle
C. stallion with previous infection with Taylorella equigenitalis
D. A stallion with a positive bacterial culture from a pre-ejaculate swab
The correct answer is a stallion with a previous infection with Taylorella equigenitalis. This organism is thought to be eradicated in the United States but is the causative agent of contagious equine metritis, which can lead to infertility (there is usually no clinically apparent disease in the stallion). It is okay to breed a stallion with a history of coital exanthema (Equine herpesvirus-3) as long as all lesions are cleared. A 180-degree rotation of the testicle is common and of no clinical significance as is a positive bacterial culture from a pre-ejaculate swab; however, heavy growth of Pseudomonas or Klebsiella may make you think twice, as they can be associated with causing endometritis in mares.
The owner of a new beef ranch on poor volcanic soil asks you to evaluate 2 steers. They are representative of an ongoing herd problem of chronic diarrhea and respiratory disease that is unresponsive to antibiotic treatment. On physical exam, you notice achromotrichia, ill thrift, and a temperature of 103F (39.4 C) in both steers. You perform a transtracheal wash in one of the steers and it comes back positive for Pasteurella multocida. What is your diagnosis?
Selenium deficiency
Copper deficiency
Pasteurella pneumonia
Bovine viral diarrhea
The correct answer is copper deficiency. The giveaway is achromotrichia or loss of hair color. Dilution of the coat color is due to dysfunction of tyrosinase which converts L-tyrosine to melanin. In addition, copper deficient animals will have spontaneous fractures, secondary respiratory disease, diarrhea, ill thrift, decreased immunity, anemia, and poor reproduction. Selenium deficiency and BVD are actually pretty good differentials and if achromotrichia was not present either of those two are reasonable choices. Molybdenum deficiency would not result in achromotrichia. On the other hand, if there had been excess molybdenum, then the Cu:Mo ratio would be off and copper deficiency could be observed.
You examine a very ill 4-year old Holstein dairy cow on a large commercial dairy. She freshened one week ago and was producing well, until she was found down and unwilling to rise this morning when you were called. T=103F or 39.4 C, HR=90, and RR=35. The scleral vessels are dark are enlarged, her rumen is fairly empty and the motility is poor, and she appears too weak to rise. Rectal exam reveals an involuting uterus which can be retracted, discharging a brownish red mucoid non-odorous lochia through the vagina. The left rear quarter of her udder is swollen, hot, painful, and discolored (see image), and contains a serum-like secretion with clumps of fibrin in it. What is your diagnosis?
A. Coliform mastitis
B. Metritis
C. Grain overload
D. Hypocalcemia (milk fever)
E. Displaced abomasum
This is a case of severe acute coliform mastitis, and the absorbed endotoxin (LPS) is causing many of the systemic signs observed. The cow needs to be aggressively treated with IV fluids, NSAIDS, and supportive nursing. The gland should be frequently milked out. The use of both intramammary and systemic antimicrobial drugs to which most coliforms are susceptible is still controversial, but is often done in cows in a severe state of illness as in this case. While this cow may have secondary hypocalcemia, treatment with calcium needs to be approached cautiously, as endotoxic animals have very sensitive myocardium and arrest may occur if calcium is given IV. If given, preferred routes of calcium administration would be subcutaneous or oral.
Hydroallantois is a disorder of the placenta (chorio-allantois) that results in rapid accumulation of 100-200 liters of watery, clear fluid during the last trimester. The cow develops a rounded appearance to the abdomen and it is usually not possible to palpate the fetus or placentomes. The cow often becomes sick with anorexia, decreased rumen motility, dehydration and weakness. She may go down or rupture the prepubic tendon. The prognosis for the fetus is guarded and even with treatment, the cow will likely be infertile. Induction of parturition or C-section are treatment options but the majority of calves are not viable and the dam rarely has normal colostrum. If the pregnancy is terminated, it is unlikely that the cow will have a productive milk cycle. Usually salvage for slaughter is the preferred option unless the fetus is considered valuable and the cow is near term.
Hydramnios is a disorder of the fetus, and the placenta itself is normal. The condition is typically characterized by gradual accumulation of thick viscous fluid during the later part of gestation. The cow develops a pear shaped caudal view. The fetus and placentomes are usually palpable and the cow is usually clinically well. Pregnancy usually goes to term and a small, deformed fetus is delivered. The cow has a fair to good prognosis for life and fertility. The cow may be induced or allowed to go to term depending on her condition.
The correct answer is right atrial enlargement. This ECG finding is known as P pulmonale and is characterized by tall slender peaked P waves greater than 0.4mV. Many times these patients have a history of chronic pulmonary disease.
Left atrial enlargement on an ECG is known as P mitrale. In this case, an increase in duration of the P wave is seen. Usually they will last at least 0.05 seconds. The reason you see these electrical changes is because of the resulting vectors that are produced by having a certain portion of the heart enlarged.
You are called to a small beef and sheep ranch where the owner is concerned about a 1-year old steer which has cloudy eyes, mucoid nasal discharge, thickened and cracked skin, and diarrhea. You examine the animal and find T=107F or 41.7 C, HR=105, RR=40, corneal opacity and thick white nasal discharge (see photo), thick cracked skin all over the animal, enlarged prescapular lymph nodes, and diarrhea with small amounts of blood in it. There are also some oral erosions.
Based on the PE you tentatively diagnose this condition.
Vesicular stomatitis
Bovine papular stomatitis
Gossypol toxicity
Bovine viral diarrhea (BVD)
Malignant catarthal fever MC
MCF is caused by a herpes virus carried by sheep in North America and called ovine herpesvirus type 2. The virus affects lymphocytes and allows the animal’s own killer cells to attack blood vessels, resulting in arteritis. Arteritis results in multisystemic signs, high fever, and enlarged lymph nodes. The acute severe form such as described here is usually fatal.
While a small number of cattle with BVD may develop corneal opacity, they do not usually have the enlarged lymph nodes and the combination of other signs seen with MCF.
It is March and you are called to a beef ranch because several beef cows on lush pasture have been found dead and another is staggering. according to the rancher. By the time you arrive this cow is down on her side with her legs paddling. The HR=140 and is pounding, while T=103F (39.4 C). The eyelids are fluttering, there is nystagmus, and champing of the jaws. Which of the following disorders fits these signs best?
Lead poisoning
Hypomagnesemia
Hypocalcemia
Copper deficiency
Hypokalemia
Hypomagnesemic tetany (grass tetany) can cause all of these signs. It usually occurs in cold or cool weather in pastured lactating beef or dairy cows. Lush pastures that are high in potassium and nitrogen and low in magnesium and sodium are most often involved.
Hypocalcemia may cause similar signs in periparturient cows (milk fever).
