p1 and p3 equine med

What is the best prevention for AHS?

Destroying the vectors habitat with insecticides

The presence of high fever and pharyngeal or submandibular lymph node abscesses are characteristic signs of:

strangles

 A contagious disease characterized by pneumonia and serial development of ulcerating nodules in the skin and upper respiratory tract

glanders

Abortion in EHV infected animals occurs during _______

late gestation

Which aspect of the inflammatory process are most affected by NSAIDs?

pain response

Which of the following causes abortion in mares, with typical fetal lesion that include hepa.. and bronchiolitis?

 Equine herpesvirus-1 infection

Where does EHV establish its latency?

Trigeminal ganglia

Equine herpesvirus-4 causes

Respiratory disease and abortion

Which of the following is NOT a diagnostic procedure of Strangles?

Esophageal lavage

It is the etiological agent for coital exanthema

EHV-3

What is the most virulent equine herpesvirus with clinical manifestations of respiratory disease, abortion, neonatal death and paralysis?

EHV 1

Which of the following is NOT a lesion related to Equine Viral Arteritis infection?

Interlobular pulmonary edema in the lungs of the aborted fetus

It is the primary mode of transmission of  Equine Viral Arteritis.

Respiratory route

Vasculitis is a common lesion related to EVA. It is related to the endothelial cell hypertrophy leading to fibrinoid necrosis of which layer of the artery wall?

tunica media

It is the principal vector of African Horse

Sickness.

Culicoides imicola

Which of the following is a cardiac lesion in related to African Horse Sickness?

Epicardial and endocardial ecchymosis

It is a gram-positive, capsulated bacteria with B-hemolytic characteristic.

 Streptococcus equi

 Which of the following is TRUE about EVA?

The transportation of the EAV to the bronchial lymph nodes is done by ....... CD3+ T-lymphocytes

Which of the following is a treatment for equine mange?

 2% lime sulphur as spray for 7-10 days interval for 3 or more treatments

Which sample is best for isolation of equine viral arteritis virus from infected horse

Heparinized blood

What is the BEST prevention for horses from ElA?

Quarantining new horse stock will decrease the risk of transmitting the

A 3-year-old Thoroughbred colt is evaluated because of a two-day history of nasal discharge and a decreased appetite. He is housed in a stable with 15 other 2- to 4-year-old horses

Isolate all horses who have fever

A 2-year-old Quarter horse is being evaluated because of pyrexia,anorexia.... examination shows a bilateral nasal discharge and retropharyngeal swelling ...... most likely diagnosis?

Strangles

Which of the following is NOT TRUE about Equine Influenza Virus?

 The virus can spread as far as 50 yards once the infected horse sneeze

Confirmatory testing for Glanders is done by:

 Histopathological study of the nodules, ulcers, and scar formation

In Mallein test, positive result would show which of the following

Swelling of the eyelids in 1-2 days

Crusts reveal parallel rows of Gram-positive cocci resembling “railroad tracks. ” What is the causative organism?

Dermatophilus congolensis

A horse presents with pyrexia, dependent edema, conjunctivitis, photophobia, abortion, and temporary infertility in stallions. What lesion is likely identified microscopically?

Fibrinoid necrosis of small arteries with lymphocytic vasculitis

Three horses from separate farms present with respiratory disease. Horse A Horse B Horse C question

Equine influenza → Equine herpesvirus 1 → Equine viral arteritis

Which finding would most strongly favor equine influenza (EI) compared to equine herpesvirus (EHV) infection?

Short incubation period

During the early pathogenesis of equine viral arteritis (EVA), which type of leukocytes transport the virus from the respiratory tract to the regional bronchial lymph nodes?

CD14+ monocytes and CD3+ lymphocytes

Which lesion best differentiates the cardiac form from the pulmonary form of African horse sickness?

Yellow gelatinous edema of the fascia over the head

 A horse infected with EVA exhibits respiratory signs alongside severe edema of the limbs, ventral abdomen, and scrotum. What microscopic pathology explains the development of this pronounced edema?

 Viral replication inside endothelial cells leads to widespread necrotizing arteritis, compromising vascular walls and increasing permeability

Which parasitic larva is responsible for Summer Sores?

Habronema spp

Which pulmonary lesion would most strongly support

Equine Herpesvirus-5 infection?

Numerous firm, coalescing nodules of fibrosis

A horse develops severe dermatitis after grazing on hepatotoxic plants

Removal of the horse from sunlight

 A 3-month-old foal presents with a high fever, tachypnea, increased respiratory effort, and a harsh cough. what is the diagnosis

Rhodococcus equi

A veterinarian suspects ringworm, but PCR results are negative after samples were collected from chronic lesions. What is the most likely explanation?

Early lesions are preferred

How many days can a horse infected with equine influenza virus (EIV) shed the virus via nasal discharge?

upto 10 days

A horse grazing on lush pasture during summer develops acute sloughing, blistering, and severe necrosis of the skin, restricted exclusively to unpigmented markings on the limbs and face. Explain pathogenesis of pigment spread

Melanin pigments in the dark skin absorb and dissipate ultraviolet radiation, preventing the activation of accumulated circulating photodynamic compounds like phylloerythrin

What are the classic gross pathological features of the pulmonary fibrotic lesions identified in Equine Multinodular Pulmonary Fibrosis (EMPF)?

Numerous pale tan-white, firm, discrete or coalescing nodules ranging from under 1 cm to 10 cm in diameter

What is the recommended vaccination schedule frequency listed for non-pregnant horses under 5 years of age for EIV?

Every 6 months

What best describes the histopathology of afibroblastic sarcoids?

Atypical fibroblasts arranged in interlocking bundles

A 12-year-old gelding presents with progressive weight loss, exercise intolerance, tachypnea, and a harsh, dry cough. Endoscopy shows no active upper airway masses, but thoracic radiography reveals a distinct, diffuse nodular pattern.

EHV-5

A 5-year-old Quarter Horse mare presents during July with intense pruritus, anxiety, and a saw “rat tail” appearance due to vigorous self-trauma and rubbing. which immune pathway

 Type IV hypersensitivity via T-lymphocytes

 A 3-year-old Thoroughbred racehorse performs poorly in a race. Endoscopic examination performed 90 minutes post-exercise reveals a stream of blood in the trachea.

Pulmonary capillary stress failure due to extremely high transmural pressure gradients

A 5-year-old Gelderland gelding presents with severe pruritus, crusting, and alopecia along the dorsum, mane, and tail head that worsens every summer. A skin biopsy confirms a Type I and Type IV hypersensitivity pattern.

Implementing allergen-specific immunotherapy tailored to Culicoides hypersensitivity antigens

 A 6-year-old Quarter Horse stallion presents with hematuria observed exclusively at the end of micturition following strong contractions of the bulbourethral muscle. pathogenesis

Mucosal rupture of the dorsal ischial urethra

Inflammatory lesions of the mitral valve are least likely to be accompanied by:

Pulmonary emboli

A breeding mare presents with mucopurulent vaginal discharge 12 days after natural mating with a valuable stallion. Bacterial culture confirms Taylorella equigenitalis.

Clitoral sinuses/fossa & urethral fossa

During cardiac catheterization in a healthy adult horse, what is the expected physiological pressure within the right ventricle

 19-25mmHg

Fumonisin B1 toxicosis impairs sphingolipid biosynthesis in equine tissues. Which specific enzyme is directly inhibited by Fumonisin B1 to trigger this metabolic disruption?

Ceramide synthase

Which two diagnostic procedures are primary for confirming a clinical diagnosis of infective endocarditis and identifying the underlying causative organism?

Echocardiogram & bacterial culture

A 3-year-old gelding candidate is found to have bilateral abdominal cryptorchidism. What

is the effect of intra-abdominal thermal retention on testicular cellular function?

Loss of spermatogenesis with maintained Leydig cell androgen production

 At therapeutic levels, digoxin causes:

Increased cardiac contractility

How is the Caslick Index calculated to objectively evaluate a mare's anatomical predisposition to pneumovagina?

Multiplying effective vulvar length in centimeters by angle of declination in degrees

Which bacterial pathogen is specifically associated with vegetative endocarditis, jugular vein thrombosis, and intestinal serosal hemorrhagic striae in horses?

Actinobacillus equuli

A horse presents with acute severe colic, congested mucous membranes, sweating, pollakiuria, and an elevated PCV after consuming newly purchased alfalfa hay. Serum biochemistry reveals significant electrolyte imbalances. Which biochemical profile aligns with blister beetle toxicosis?

Hypocalcemia & hypomagnesemia

An owner calls you to examine an 18-year old thoroughbred gelding with a 4- month history of progressive exercise intolerance.
Which statement is most accurate?

The exercise intolerance is probably not due to cardiac disease

An owner calls you to examine an 18-year old thoroughbred gelding with a 4- month history of progressive exercise intolerance.
The most appropriate course of action is to:

Perform a respiratory examination

When evaluating organophosphate exposures in horses, different agents exhibit variable minimum toxic thresholds. Which organophosphate compound has a  minimum reported toxic dose of 25 mg/kg in equids

Dichlorvos

A broodmare presents with edematous swelling of the lips and nose, alongside marked

icterus 6 days after an unseasonal grain change. Blood is collected for a diagnostic serum chemistry panel, revealing: elevated GGT, AST, TBIL. 10 days following blood collection, the patient died.

Fumonisin

Which specific tubular functional defect characterizes Type 1 (Distal) Renal Tubular Acidosis in horses?

 Impaired hydrogen ion secretion in distal tubule intercalated cells

 In the medical management of toxicosis, why is 2-PAM (pralidoxime chloride) explicitly avoided/contraindicated in carbamates poisoning?

Ineffective in carbamate toxicity compared to organophosphate toxicity

You examine a 17-year-old thoroughbred gelding with ventral abdominal & limb edema. The rectal temp is 37.7C, the heart rate is 66 beats/min, and there is a jugular pulsation & distension.

Gelding has heart failure that could be due to valvular disease or myocardial disease

Which medication is identified as the drug of choice (DOC) for the pharmacological conversion of atrial fibrillation to normal sinus  rhythm in horses?

Quinidine sulfate

What is the most common pathological arrhythmia in horses?

Atrial fibrillation

 What is the most common nonpathological arrhythmia in horses?

Second-degree atrioventricular block

A horse evaluated for lethargy, muscle trembling, and tachycardia exhibits hyperchloremia, hypokalemia, and neutral to alkaline urine pH (> 5.5) on laboratory analysis.

Intravenous sodium bicarbonate administration & potassium replacement

A 6-year-old Quarter Horse gelding presents with acute neurological signs including ataxia, depression, head pressing, unilateral blindness, and pharyngeal paralysis, progressing rapidly to recumbency and death within 18 hours.

Fumonisin

An equine patient accidentally exposed to an organophosphate insecticide exhibits profuse

salivation, miosis, frequent urination, watery diarrhea, and severe dyspnea.

Muscarinic acetylcholine receptors

During laparoscopic surgery on a cryptorchid stallion, the surgeon locates the retained undescended testis intra-abdominally adjacent to the deep inguinal ring. In a healthynon-cryptorchid stallion, what anatomical structure normally traverses the inguinal canal into the scrotum?

Spermatic cord

 To confirm a diagnosis of uroperitoneum, which peritoneal fluid finding relative to serum is considered the diagnostic gold standard?

Peritoneal fluid creatinine concentration at least twice that of serum creatinine

Three horses on the same farm develop different clinical syndromes after consuming feed from the same general storage area. Horse ABC again

A—Fumonisin; B—Cantharidin; C— Organophosphate

 Which serum electrolyte profile is characteristic of uroperitoneum in newborn foals?

Hyperkalemia, hyponatremia, hypochloremia

A horse with organophosphate poisoning is treated with atropine. Which clinical effects should the veterinarian primarily expect this drug to counteract?

 Muscarinic effects

 A diagnostic workup yields the following laboratory results: PCV is elevated, hypocalcemia, hypomagnesemia, elevated CK, low urine SG. Which toxin is responsible?

Cantharidin

Which cardiac rhythm disturbance is recognized as the most common physiological (benign) arrhythmia in resting horses that characteristically disappears during walking or light exercise?

Second-degree atrioventricular block

A multiparous broodmare with a sunken anus and a cranially tipped vulva develops chronic endometritis. What primary anatomical defect causes pneumovagina in this horse?

Breakdown of the physical seal dorsal to the pelvic brim

A Quarter Horse stallion presents with post- ejaculatory hematuria. Endoscopy reveals a mucosal defect in the dorsal ischial urethra. Which surgical technique is indicated for managing this condition?

Subischial perineal urethrotomy

A poisoned horse develops muscle fasciculations followed by weakness. The veterinarian recognizes these signs as part of the nicotinic effects of organophosphate poisoning. Which mechanism best explains these signs?

Excessive stimulation of nicotinic acetylcholine receptors

What classic post-mortem brain lesion is diagnostic for equine leukoencephalomalacia caused by Fumonisin  toxicity ("moldy corn poisoning")?

Liquefactive necrosis of the cerebral white matter

When evaluating laboratory diagnostics for a horse suspected of blister beetle (Cantharidin) ingestion, which combination of CBC, urinalysis, and serum chemistry findings provides the strongest diagnostic confirmation?

 Increased PCV, low urine SG, elevated CK, hypocalcemia, hypomagnesemia

Leukoencephalomalacia is caused by:

Ingestion of corn infested with Fusarium spp.

 In horses diagnosed with infective endocarditis, which cardiac valve is most frequently affected by vegetative mass formation?

 Mitral valve

 A gelding presents with dysuria, urine dribbling, and scalding. Urinalysis reveals turbid urine with elevated protein. Which ultrasonographic finding confirms a diagnosis of acute bacterial cystitis?

Diffuse wall thickening with corrugated mucosa

What is the recommended oral Valacyclovir dosing regimen for this stallion?

27 mg/kg q8h for 2 days, 18mg/kg BID for 8 days

A farm's corn is found to contain approximately 15–22 ppm fumonisin B1. The veterinarian warns the owner about the potential risk to the horses. Why is this concentration concerning?

 It falls within the concentration described as toxic

A horse develops hypersalivation, miosis, frequent urination, diarrhea, dyspnea, muscle fasciculations, weakness, and eventually seizures after exposure to an insecticide. What toxicosis is MOST likely?

Organophosphate

A horse accidentally receives excessive exposure to an organophosphorus insecticide. Within hours, it develops hypersalivation, miosis, diarrhea, frequent urination, and dyspnea. What explains these clinical signs?

 Accumulation of acetylcholine due to acetylcholinesterase inhibition

A horse with suspected cantharidin toxicosis develops severe shock and organ failure. Which sequence BEST represents the progression?

Depression → colic → GI distress → shock → organ failure → death

Which parasite is recognized as an etiology of myocarditis in horses due to larval tissue migration and vascular damage?

Strongylus vulgaris

 What is the primary pathophysiological cascade leading to these right-sided clinical

signs?

 Chronic pulmonary disease → increased pulmonary vascular resistance → elevated pulmonary artery pressure → increased right ventricular afterload → right-sided heart failure

Ultrasonography of an older maiden mare reveals an enlarged uterus filled with echogenic exudate exhibiting a 'snowy' appearance. Manual examination identifies cervical stenosis. What structural alteration initiates pyometra in the mare?

 Fibrotic, inelastic cervix with transluminal adhesions

 Which combination of pathological mechanism and pharmacological intervention is correct for managing this specific toxicosis? organophosphate

Inhibition of acetylcholinesterase leading to acetylcholine accumulation; administer Atropine and Pralidoxime chloride (2-PAM)

Gamma-Glutamyl Transferase (GGT): 195 U/L (Severely Elevated) Aspartate Aminotransferase (AST): 780 U/L (Severely Elevated) Total Bilirubin (TBIL): 7.2 mg/dL (Severely Elevated) Correlating the findings with disease progressions, what is the definitive diagnosis?

Fumonisin

An 11-year-old Thoroughbred stallion presents with a low-grade fever, weight loss, a new holosystolic murmur, and intermittent shifting hindlimb lameness. Which pathologic

process best explains the origin of the shifting lameness?

Thromboembolism from vegetative endocarditis