Equine Disease Quiz 1

What are the characteristics that make up the signalment of a horse?

• age

• sex

• breed

• color

• reproductive status

• intended use of the horse

What are the 2 major components that make up the history of a horse when they are presented to a clinic?

History of the current problem and general history

Why are your hands important tools when it comes to performing a physical exam on a horse?

Your hands help you palpate for areas of swelling, erythema, lacerations, changes in mucus membrane color, signs of lameness, increased muscle mass, muscle atrophy, and coldness.

What is the normal temperature for a horse at rest?

99.0 - 101.5 F

Why is it important to auscultate the heart and arterial pulse simultaneously?

It is important because you need to make sure that every heartbeat has a palpable pulse wave. If the heartbeat is not accompanied by a pulse wave, a pulse deficit will occur.

Discuss the significance of a 2nd degree AV block heart murmur.

A 2nd degree AV block is a heart arrhythmia caused by the failure of the electric current generated by the atria to reach the ventricles. It is significant because it is the most common cause of irregularity in horses and results in “dropped” pulses, which occur every 3rd-4th beat. It is also significant because 2nd degree AV blocks are considered a normal finding, but should still be noted on the chart.

What does checking a horse’s CRT help determine?

hydration of the horse and blood perfusion

What are the 2 main things that are looked for while examining the quality of a horse’s teeth?

malocclusion and sharp points or hooks

What are the landmarks used when listening to a horse’s heart sounds?

The landmarks are at the level of the shoulder and the point of the elbow, and may need to be listened to on both sides.

List lung sounds that are abnormal when listening to a horse’s lungs.

• wheezes

• crackles

• gurgling

• moist sounds

• bubbling

• squeaking

List the 4 abdominal quadrants.

• Upper Right (UR): Base of cecum

• Lower Right (LR): Body of cecum

• Lower Left (LL): Large colon

• Upper Left (UL): Small intestines

What are the common areas for local and topical medication applications?

• skin

• eyes

• interal surface of lungs

• rectum

• uterus

• joints

Discuss the difference between ointments and creams when it comes to using them as topical medications.

Ointments do not penetrate the skin, while creams are best for topical skin penetration

When are intradermal injections commonly used?

when performing intradermal skin tessts for allergens

If a horse aspirates medication, what can it potentially cause?

aspiration pneumonia

Define systemic medications

Systemic medications are medications that are administered through injections, either subcutaneously, intramuscularly, or intravenously. They are distributed throughout the entire system via the bloodstream and affect the entire body as a whole rather than a specific area.

List the different forms of systemic medication administrations.

• Subcutaneous (SQ)

• Intramuscular (IM)

• Intravenous (IV)

What are the 3 common sites for intramuscular injections?

• neck

• brisket

• rump

If an IV medication is given in the artery, what can happen to the horse?

This is called intra-arterial injection and can cause adverse reactions such as acute collapse

List the normal resting heart rate for an adult horse and a foal.

• adult horse = 28-44 bpm

• foal = 60-80 bpm

Explain the difference between systole and diastole?

Systole pumps blood out of the ventricles to the body and represents the heart’s contraction phase. Diastole is the relaxation phase of the cardiac cycle, where the heart is able to relax and refill with blood. The systole phase is shorter in duration than diastole and occurs between S1 and S2. The diastole phase is longer in duration than systole and occurs from the end of S2 to the beginning of S1.

Define stroke volume.

Stroke volume is the amount of blood pumped by the heart in one contraction or beat

Which arrhythmia is not associated with underlying heart disease in horses?

atrial fibrillation

Explain the 2 types of heart murmurs.

• Physiologic heart murmurs are not associated with structural abnormalities.

• Pathologic heart murmurs are reflective of heart pathology

Explain the difference between a grade 1 heart murmur and grade 6 heart murmur.

A grade 1 heart murmur is very soft, and extended auscultation is needed for detection. A grade 6 heart murmur is very loud and has a palpable thrill. It can be detected with the stethoscope held off contact.

What is the most common cause of systolic murmurs in horses?

Mitral regurgitation, this is the result of a dysfunctional mitral valve, in which blood is allowed to flow backwards through the valve.

Explain what happens in the lungs to cause bacterial infections.

Colonization of the lungs by opportunistic bacteria because the defense mechanisms are down, and they are immunocompromised.

What are the causative agents associated with viral respiratory infections?

• Equine Herpes Virus (EHV)

• Influenza

• Equine Viral Arteritis (EVA)

What are the clinical signs for Reactive Airway Disease in horses?

small airway constriction and increased mucus production

Define pleuropneumonia in horses

A bacterial infection that involves both the lungs and the pleural space, usually followed by pneumonia. Some predisposing factors for horses include long-distance travel, general anesthesia, and strenuous exercise.

Explain the cause of Exercise-Induced Pulmonary Hemorrhage (EIPH) in horses.

EIPH is most commonly seen in racehorses and sport horses. It is caused by elevated pulmonary vascular pressures during periods of extreme exercise. This causes thickening of the walls of pulmonary vessels, decreased luminal diameter in pulmonary capillaries, in conjunction with elevated intravascular pressure.

Explain what is happening when a horse is experiencing Recurrent Laryngeal Nerve Paralysis.

Recurrent laryngeal nerve paralysis is the paralysis of usually the left arytenoid cartilage and vocal fold, which is caused by loss in fibers in the recurrent laryngeal nerves. This condition causes a resistance in airflow, which in turn causes increased respiratory effort.

What is the most common fungal organism associated with Guttural Pouch Mycosis?

Asperigillus species

What bacterial pathogen causes Strangles in horses?

Streptococcus equi

Explain what Equine Rhinopneumonitis is and how it is transmitted?

Equine rhinopneumonitis is a highly contagious respiratory disease caused by equine herpesvirus type 1 and type 4. It is transmitted through inhalation of aerosolized respiratory secretions and direct contact with fomites.

Explain what dorsal displacement of the soft palate is and the possible causes associated with it.

Displacement of the soft palate occurs when the caudal border of the soft palate moves over the epiglottis, causing an obstruction. Possible causes include upper respiratory inflammation secondary to infection and congenital defects in the epiglottis.

What is the first thing you should do when starting a physical exam on a horse?

start observations from a distance

What are the locations that we can gather a pulse rate from?

• facial artery

• tranverse facial artery

• coccygeal artery

• dorsal metatarsal artery (digital pulses)

What is the respiratory rate for a horse and foal?

• adult horse = 6-16

• foal = 80-90 (newborn)

  • 20-40 (first week)

T or F: It is normal for a horse to breathe from it’s mouth.

False

Blue MM or cyanosis can mean what?

low oxygen

Brick red MM can mean what?

bacterial septicemia or septic shock

Yellow or icterus MM means what?

abnormal hemolysis of red blood cells

T or F: Never ear twitch a horse.

True

What is the skin turgor test?

A way to test the hydration status of a horse. Pinch loose skin over the lateral aspect of the neck. A hydrated animal’s skin will return to normal in approximately 1 second or less.

Which side can heart murmurs be heard on?

right

Normal gut motility is ___ borborygmi per minute in each quadrant.

1-3

Digital pulses of the front legs can be palpated on either side of the _____

sesamoid bone

Where are SQ injections usually given on horses?

the side of the neck

What gauge needle is used for SQ injections?

21-gauge needle

What vein is usually used for IV injections?

jugular

What other veins can be used for IV injections?

• lateral thoracic vein

• cephalic vein

Which gender is most commonly affected by recurrent laryngeal nerve paralysis?

male

Guttural empyema is often secondary to ____ infection

upper respiratory

Myocardial toxicity can be related to the consumption of what?

ionophores

Pre-load is influenced by ___ blood pressure

diastolic

After-load is influenced by ___ blood pressure

systemic

____ - most common, vagally caused arrythmia in resting horses

2nd degree AV block

What is the primary cause of mitral regurgitation?

degenerative valve disease

What is the most common cause of diastolic heart mrmurs in horses?

aortic regurgitaiton

Which heart valves are located on the horse’s left side?

• Pulmonary

• Aortic

• Mitral

What type of murmur is most commonly associated with systole?

mitral regurgitation

What are the factors that determine the type of preventative health program needed for a horse?

• expected exposure

• management styles

• personal preferences of attending veterinarians and horse owners

What is being tested for with a Coggins test?

Equine Infectious Anemia

What factors determine the vaccine schedule for a horse?

• age of the horse

• anticipated exposure

• duration of immunity provided by the vaccine

What is the key factor to a seccussful fly control protocol?

good sanitation

These internal parasites live primarily in the terminal large intestine, and the females protrude from the anus and glue eggs to the skin folds around the anus of a horse.

Oxyuris Equi, also known as pinworm

What parasites are associated with the dewormer Fenbendazole?

• Acarids

• Strongyles

• Pinworms

What parasites are associated with the dewormer Pyrantel pamoate?

• Asscarids

• Small Strongyles

• Tapeworms

What parasites are associated with the dewormer Ivermectin?

• Ascarids

• Strongyles

• Threadworms

• Lungworms

• Stomach worms

• Bots

• Pinworms

What parasites are associated with the dewormer Moxidectin?

• Acarids

• Strongyles

• Bots

• Pinworms

What parasites are associated with the dewormer Praziquantel?

• Ascarids

• Small Strongyles

What structure within the hoof attaches the hoof wall to the coffin bone?

the laminae

What is the average growth of a horse’s hoof on a monthly basis and how often should hooves be trimmed based on this average growth rate?

Horse hoofs grow on average one-quarter inch per month and need to be trimmed every 6-8 weeks

Define thrush.

Thrush is caused by anaerobic bacteria that grow in moist, dark conditions, such as the hoof frog. Cleaning can help dry out the foot and create an aerobic environment where the bacteria can no longer thrive.

What is immunological memory?

This is the immune system’s ability to remember specific microbes or foreign material. This allows the body to mount a more effective defense mechanism to repeated exposures to the same microbe or foreign antigen.

What is the difference between a live vaccine and a modified live vaccine?

Live vaccines contain live agents that are capable of replication in the horse, yet have reduced pathogenicity.

Modified live vaccines contain naturally occurring pathogens that have come from reduced cell culture, from variants of other species, or that have temperature-sensitive mutations.

How often should a tetanus vaccine be given to a previously vaccinated horse?

Tetanus requires a second dose 4-6 weeks after the initial vaccine and then revaccination annually.

How often should a rabies vaccine be given to a previously vaccinated horse?

Rabies requires an annual revaccination after the initial dose

Risk based vaccines are given to a horse based on the anticipated degree of risk, what factors are associated with the degree of risk?

• the horse’s geographical location

• the horse’s use

• the horse’s contact with other equine individuals

What is the causative agent of tetanus?

Clostridium tetani

Starting with the reservoir hosts, how is the west nile virus transmitted to horses?

The reservoir hosts are birds. Mosquitos then bite the bird, become carriers, and transfer the disease to the horses through their bite.

What are the common animal reserviors of rabies in north america?

• skunks

• foxes

• raccoons

• bats

List the common areas that a horse can be bitten to contract the rabies virus.

• muzzle

• face

• lower limbs

Which types of horses have increased risk factors when it comes to the Equine Influenza Virus?

• Younger horses between the ages of 1 and 5 years old

• Horses that have frequent contact with many horses

• Unprotected or unvaccinated horses

How is the Equine Arteritis Virus (EVA) transmitted?

Transmission occurs through infected respiratory secretions and the semen of infected carrier stallions

What is the causative agent of the Potomac Horse Fever, and what is a general symptom associated with this disease?

The causative agent is Neoriskettsia risticii and the general symptom is diarrhea

What is the causative agent of Anthrax?

Bacillus anthracis

What is botulism and what is the causative agent?

Botulism is a highly fatal and progressive neurotoxic disease, and it is caused by Clostridium botulinum

What is Equine Infections Anemia, and what does it cause?

EIA is a persistent viral disease of horses that causes anemia, fever, and weight loss.

What permanent IDs are used on horses that are carriers of EIA?

• tattoos

• brands

• microchips