A 3-year-old mixed breed dog is presented with a 1-week history of fainting and lethargy.

On physical exam the dog appears shocky and weak with a slow capillary refill time.

An ECG shows the following image.

The history, bradycardia, shock, and ECG that lacks P-waves all point towards persistent atrial standstill, likely due to hyperkalemia.

Which conditions are on the differential diagnosis list for high potassium associated with atrial standstill?

While conducting a routine physical on a 4 year old male intact bulldog, an irregular heart rhythm with a slow rate that is markedly slower on expiration is audible during auscultation.

What should be done next?

What test is indicated in a dog that presents with sinus bradycardia, sinus arrest or sinoatrial block?

A 5-month old English sheepdog with unilateral periocular alopecia is presented for a routine vaccination visit.

A skin scrape shows the following.

What is the treatment plan?

A 5-year-old lactating Holstein dairy cow is being evaluated for a 2-month history of watery diarrhea, weight loss, and decline in milk production.

On examination, the cow is bright, alert and responsive, but unthrifty and very thin, with a soft intermandibular swelling.

Which one of the following diseases is the most likely diagnosis?

A five-year old lactating Holstein dairy cow is being evaluated for a two-month history of watery diarrhea, weight loss, and decline in milk production.

On examination, the cow is bright, alert and responsive, but unthrifty and very thin, with a soft intermandibular swelling.

What is the most appropriate management of this herd?

A 7 year-old neutered male Rottweiler-mix dog from the Southern U.S. in poor body condition presents with a 1-month history of exercise intolerance, non-productive cough and heavy breathing.

The dog lives outside the house, last received routine vaccinations 4 years ago, and does not receive any other medications. Physical exam reveals mild cyanosis, ascites, temperature of 102.1 ºF, (38.9 ºC).

What is the most appropriate test to do to support the presumptive diagnosis?

140 wallabies are serologically tested for a disease.

35 wallabies test seropositive and 105 test seronegative.

However, postmortem data reveals 5/35 of the seropositive wallabies are disease free and 4/105 of the seronegative wallabies are diseased.

What is the predictive value positive of this serologic test?

Hint: If you have no idea how to start, pick any answer and follow the calculation steps given in the explanation.

140 wallabies are serologically tested for a disease.

35 wallabies test seropositive and 105 test seronegative.

However, postmortem data reveals 5/35 of the seropositive wallabies are disease free and 4/105 of the seronegative wallabies are diseased.

What is the predictive value negative (PVN) of this serologic test?

140 wallabies are serologically tested for a disease.

35 wallabies test seropositive and 105 test seronegative.

However, postmortem data reveals 5/35 of the seropositive wallabies are disease free and 4/105 of the seronegative wallabies are diseased.

What is the sensitivity of this serologic test?

140 wallabies are serologically tested for a disease.

35 wallabies test seropositive and 105 test seronegative.

However, postmortem data reveals 5/35 of the seropositive wallabies are disease free and 4/105 of the seronegative wallabies are diseased.

What is the specificity of this serologic test?

You serologically test 100 Siberian box turtles for galloping halitosis.
27 turtles test seropositive and 73 test seronegative.
However, molecular testing reveals 3/27 of the seropositive turtles are disease free and 10/73 of the seronegative turtles are diseased.

The entire fur-bearing turtle industry depends on your answer: What is the specificity of your serologic test?

Under what conditions is a very sensitive test used?

Under what conditions is a very specific test used?

For the last 10 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?

You serologically test 100 Siberian box turtles for galloping halitosis.
27 turtles test seropositive and 73 test seronegative.
However, molecular testing reveals 3/27 of the seropositive turtles are disease free and 10/73 of the seronegative turtles are diseased.

The entire fur-bearing turtle industry depends on your answer: What is the Predictive Value Negative (PVN) of your serologic test?

A practice is using an FeLV test with a sensitivity of 90% and a specificity of 95%.

Assuming the prevalence of feline leukemia in the area is 5%, what is the predictive value positive (PVP) of the test?

A practice is using an FeLV test with a sensitivity of 90% and a specificity of 95%.

Assuming the prevalence of feline leukemia in the area is 5%, what is the predictive value negative (PVN) of the test?

A SLAP® heartworm antigen test with a reported sensitivity 96% and specificity of 98% is being used.

Assuming the prevalence of heartworm in the area is 10%, what is the predictive value positive (PVP) of the test?

What statement is most correct regarding a highly sensitive test?

What statement is most correct regarding a highly specific test?

What is the primary factor associated with pregnancy toxemia in ewes and goats?

Which of these is safe for pets to eat?

A 4-year-old Saanen goat is presented that is off feed and feverish, with a swollen and draining abscess associated with her left prescapular lymph node.

Caseous lymphadenitis (CLE) is suspected. What is the causative organism?

Several piglets in a group weaned 10 days ago in the nursery facility of a large commercial swine operation were found dead.

On evaluation, some weaners have swelling around the eyes and forehead.

Some are in lateral recumbency and dyspneic.

Necropsy of the dead piglets reveals subcutaneous and submucosal edema.

The most likely causative organism is…