Equine Flashcards
You have diagnosed a horse with African Horse Sickness with _[test]__. Your next step is _____.
Diagnose with rt-PCR; report the disease.
African horse sickness (AHS) is a reportable, noncontagious, nonzoonotic, arthropod-borne viral disease of equids that is endemic to sub-Saharan Africa. AHS is a life-threatening hemorrhagic disease characterized by respiratory and circulatory impairment. It is transmitted by midges (Culicoides spp). Diagnosis is by real-time PCR assay. Control is centered around vaccination.
Clinical signs typically develop 5-7 days after infection and begin with fever and conjunctivitis. Some may recover, but many go on to develop the pulmonary and/or cardiac forms of AHS. The pulmonary form consists of acute respiratory distress, coughing, sweating, and foaming from the nostrils; this form is usually fatal. The cardiac form consists of edema of the head and neck as well as abdominal pain and depression. A characteristic sign is swelling in the indentation above the eyes (also referred to as swelling of the supraorbital fossa). About 50% of animals with the cardiac from die fo heart failure while the rest gradually recover after about one week.
African Horse Sickness is a [bacteria/virus/fungi/protozoa/helminth] transmitted by _____ and causes primarily ____ signs along with a characteristic ______ edema.
African Horse Sickness is a virus transmitted by midges (culicoides) and causes primarily pulmonary signs along with a characteristic supraorbital edema.
Anaplasma phagocytophilum
Equine Granulocytic Ehrlichiosis (formerly Ehrlichi equi)- clinical signs: fever, lethargy, tachycardia and limb edema. Microscopic observation of a morula within the neutrophil. Diagnosis can be supported via PCR assay. Spread via tick bites. Treat with oxytetracyline.
Anaplasma phagocytophilum is a gram-______ bacteria transmitted by ______ and characterized by ________ in horses.
Anaplasma phagocytophilum is a gram-negative bacteria transmitted by Ixodes spp ticks, it is characterized by fever, lethargy, tachycardia and limb edema in horses.
Name this intracellular pathogen (wright’s stain)
Anaplasma phagocytophilum
Anhidrosis means _____ and can be fatal if not addressed. The most successful treatment is _____
Anhidrosis means the inability to sweat, which can be fatal if not addressed. The cause is unknown. It tends to occur in hot humid climates and may occur in horses raised in the climate or, more commonly, horses brought into the climate. The most successful treatment is to move the horse back to a more favorable climate.
Anoplocephala are__[bacteria/virus/fungi/protozoa/prion/helminth]__in the horse. Anoplocepha magna is usually found in the _____ whereas A perfoliata is usually in the _____. Both are treated with _____. The intermediate host of Anoplocephala spp is _____.
Anoplocephala are tapeworms of horse; magnus usually found in the small intestine; perfoliata in the ileocecal junction.
Treat with pyrantel salts
involves free-living oribatid mites as intermediate hosts
The auriculppalpebral nerve block disrupts ___ to ____ muscle; this is because the auriculopalpebral nerve is part of cranial nerve ____ which is ____ only. This block allows for ____ during ocular exam of an already painful eye.
The auriculopalpebral block disrupts motor to the orbiculoris oculi muscle; this is because the auriculopalpebral nerve is part of CN VII which is motor only (facial nerve). This allows for eyelid akinesis during ocular exam of an already painful eye.
Bog spavin refers to _____ of the _____ joint(s) whereas bone spavin refers to ______, typically at the ______ joint(s).
Bog spavin is edema of the tarsocrural (tibiotarsal) joint whereas bone spavin is osteoarthritis of the lower tarsal joints, usually the
tarsometatarsal and the distal intertarsal joints.
This clinical sign is referred to as
bog spavin
If a flexion test of the hock worsens lameness but blocking the distal tarsal joint improves lameness, this is suggestive of _____
bone spavin
The causative agent of lyme disease is ______, which is a gram-_____ __[shape]____ transmitted by _________. It can be treated with _______
Borrelia burgdorferi; gram negative spirochete; transmitted by Ixodes scapularis (blacklegged tick)
oxytetracycline of doxycycline
Low-grade fever, stiffness and lameness in more than one limb, muscle tenderness, hyperesthesia, swollen joints, lethargy and behavioral changes are all clinical signs of ______
Lyme disease
Burkholderia mallei
Glanders - can be identified on smears make from fresh lesions as mainly extracellular straight gram-negative rods with rounded ends. Diagnostic tests: PCR, ELISA, and western blot but mostly need to know that are used in international trade are complement fixation (CF) serology and the mallein test. Mallein test is considered the most reliable, sensitive and specific. It involves injection of mallein purifies protein derivative intradermally into the lower eyelid. The test is read 24 to 48 hours and a positive reaction is characterized by edematous swelling or purulent discharge. Horse should not be treated; local authorities should be notified if a case is suspected and if disease is confirmed, horses must be humanely destroyed and affected carcasses should be burned and buried. Endemic in regions of the Middle East, Africa, and South America. Affects donkeys, mules, and small ruminants. Horses can become chronic or occult carriers and shed this deadly and potentially zoonotic pathogen.
Pyramidal disease in the horse refers to _____ of the pyramidal process, usually preceded, but sometimes followed by ______ of the process. It is characterized by the thickening of the _____ and _____-like protrusion of the distal hoof wall. Treatment involves _____ removal of small fragments.
Pyramidal disease refers to periostitis and ostitis in the region of the pyramidal process of the coffin bone, usually preceded, but sometimes followed, by fracture of the process. It is characterized by thickening of the coronary band and buttress-like protrusion of the distal hoof wall. via arthroscopy or arthrotomy; arthroscopic removal of small fragments carries a good prognosis.
C. pseudotuberculosis test
internal abscesses, hemagglutination inhibition test
Cerebellar Abiotrophy (age, breeds, clinical signs)
usually observed in foals which are less than one year of age, particularly 1-6 months of age. It is mostly seen in Arabian, Oldenburg, and Gotland breeds. There is no treatment and signs may be progressive. Diagnosis is based on a good history and clinical signs such as intention tremors, lack of a menace, hypermetria, and ataxia.
Cervical vertebral malformations (Wobbler Syndrome) occurs primarily in horses of what age?
Seen primarily in horses under a year of age
Chorioptes equi is a ____ that is usually found around the ____. It can be diagnosed with _____. The lesions are ______. The treatment of choice is _____.
mange mite that is usually found around the foot and fetlock. Diagnosed with skin scraping. It causes pruritic dermatitis that can cause the formation fo papules, crusts, thickened skin, as well as alopecia. The mites are often found in feathered hair around the fetlock of draft horse. Ivermectin is the treatment of choice.
Chronic hepatitis histopathology
hepatocyte, damage, variable fibrosis, inflammatory infiltration, and evidence of biliary hyperplasia with bile stasis
Chronic seborrheic dermatitis aka ____ is thought to occur due to ____
“scratches” due to wet environment
Club foot
Condition seen in horses secondary to contracture of the distal interphalangeal joint leading to steep hoof wall and shortened toe.
Coggin’s test is used to detect ______
Coggins’ is the common name for an enzyme-linked immunosorbent assay (ELISA) which is a blood test used to screen horses, donkeys and mules for the potentially fatal viral disease Equine Infectious Anemia (EIA).
effective in diagnosing infection in chronic asymptomatic carriers
Which equine IM vaccine can cause a reaction? Is there an alternative?
Strangles vaccine is associated with a soft tissue reaction, there is now an intra-nasal vaccine available with local protection
The primary “immune organs” of the horse are the ___ and ___
lungs and colon
Commonly injured when horse flips over backwards
Ruptured longus capitis
Corynebacterium pseudotuberculosis causes what disease in horses?
“Pigeon fever” Causes ulcerative lymphangitis and abscesses in the pectoral region of horses. Treatment is aimed at hot packing the swellings and draining the abscesses. Antibiotic can be administered but have been known to prolong the disease by delay abscess formation.
Culicoides hypersensitivity aka ____ occurs during the ____ months. This is an allergy to _____. Pruritic lesions develop on the ________.
“sweet itch” Diffuse lesions, recurs seasonally in the warmer months and tends to worsen with age. Occurs due to an allergy to the saliva of the gnat. Pruritic and develop lesions on the poll, mane, and tail from self-trauma, ventral midline dermatitis can occur as well. Decrease exposure to gnats and treat with steroids.
Cutaneous glanders
Also known as Farcy. The cutaneous form develops over several months, beginning with cough and dyspnea as well. Eventually nodules develop in subcutaneous tissue along the course of the lymphatics of the legs, costal areas, and ventrum. They can rupture and excrete infectious purulent exudate. Infected lymphatics may form thickened cord-like lesions that sometimes coalesce into a string of beads appearance know as “farcy pipes.” Nodular lesions of other organs may also be found.
Dandy-Walker syndrome
Rare condition seen in Arabians and Thoroughbred foals which results in a midline defect of the cerebellum and cystic dilation of the four ventricle.
Degenerative myeloencephalopathy
Seen primarily in horses under a year of age, causes a symmetrical ataxia.
Dermatophilus congolensis most often causes ____ with ____ along the ____ of a horse. This bacteria is a __[gram stain]__, non-acid fast, facultative anaerobic actinomycete. It enters skin that is weakened by _____. Sometimes the infection is called “____”
Dermatophilus congolensis most often causes crusts with purulent exudate under them on the dorsum of a horse. This bacteria is a gram positive, non-acid fast, facultative anaerobic actinomycete. The bacteria enters the skin when it is weakened by moisture and mechanical irritation. Horses with long, wet haircoats are often affected. Lesions are commonly on the dorsum and pasterns of horses and are classically described as “paintbrush” lesions. Can be diagnosed with a direct smear preparation. Treatment includes keeping the haircoat clean and dry and penicillins if the lesions are severe. Lesions typically heal rapidly.
Infection with this bacteria is also called “mud fever”
Dermatphytosis
Crusting dermal lesions
KOH test
DIC coagulation parameters
Prolongation of the prothrombin time (PT) and the activated partial thromboplastin time (aPTT) reflect the underlying consumption and impaired synthesis of the coagulation cascade.
Fibrinogen level has initially thought to be useful in the diagnosis of DIC but because it is an acute phase reactant, it will be elevated due to the underlying inflammatory condition. Therefore, a normal (or even elevated) level can occur in over 57% of cases. A low level, however, is more consistent with the consumptive process of DIC.
A rapidly declining platelet count
High levels of fibrin degradation products, including D-dimer, are found owing to the intense fibrinolytic activity stimulated by the presence of fibrin in the circulation.
The peripheral blood smear may show fragmented red blood cells (known as schistocytes) due to shear stress from thrombi. However, this finding is neither sensitive nor specific for DIC
Dictyocaulus arnfeldi
Lungworm; donkey definitive host - Baerman test
Dourine
“covering sickness” trypanosomal (protozoa) venereal disease
notifiable, causes paralysis
Can only treat symptoms, no cure and no vaccination
50% mortality
Draschia megastoma
migrating parasite that can cause focal granulomas in the lung
Dry matter protein intake requirement
12%
Eastern Equine Encephalomylitis (EEE)
Arbovirus with zoonotic potential - “sleeping sickness”
transmitted by mosquitos
mortality can be as high at 90%
Ehrlichi equi
neutrophil, Equine Granulocytic Ehrilichiosis, lethargy, anorexia, fever, limb edema and hematology changes such as neutropenia and thrombocytopenia.
Neorickettsia (formerly Ehrlichia) risticii is the causative agent of _______. This disease can cause both ____ and ____ in the summer months. Although a trematode vector is suspected, the exact pathogenesis is still being studied. Treatment involves _____
Neorickettsia (formerly Ehrlichia) risticii is the causative agent of Potomac horse fever. This disease can cause both diarrhea and laminitis in the summer months. Diagnosis requires measurement of paired serum titer via immuno-flourescent antibodies or detection of the organism via PCR in the blood or feces. Treatment is oxytetracycline.
Enterolith in California
Magnesium ammonium phosphate due to alfalfa in California
EPM treatment
Ponazuril, Nitazoxanide, folate inhibitors (Sulfadiazine, pyrimethamine)
Equine Adenovirus
Normally found in the upper respiratory tract of the horse, but can cause a lower respiratory tract infection in immunocompromised individuals, particularly foals with those town conditions, leading to an often fatal pneumonia.
Equine Degenerative Myeloencephalopathy
Associated with a deficiency in Vitamin E. CLincial signs are usually in the form of a wide-based stance, conscious proprioceptive deficits, ataxia, paresis, and spasticity, which is worse in the hindlimbs.
Equine Eosinophilic Granuloma
The lesions are nodular, nonulcerative, and nonpruritic. They often are found in the saddle, central truncal, and lateral cervical areas and may have a gray-white central core. Older lesions may become mineralized. Both insect bites and trauma have been suggested as causes, although the occasional onset during winter in cold climates and in noncontact saddle or tack areas suggests multifactorial causes
Equine Granulocytic Ehrlichiosis
tick-borne
infectious, noncontagious, seasonal disease
rickettsial agent Anaplasma phagocytophilum
Signs may be mild. Horses <1 yr old may have a fever only; horses 1–3 yr old develop fever, depression, mild limb edema, and ataxia. Adults exhibit the characteristic signs of fever, partial anorexia, depression, reluctance to move, limb edema, petechiation, and icterus
Demonstration of the characteristic cytoplasmic inclusion bodies in a standard blood smear is diagnostic
Treat with Oxytetracycline
This disease is characterized by hindlimb ataxia (ie dog sitting), hypotonia of the tail/anus and urinary incontinence, and can affect multiple animals on the same farm. A CSF sample would show xanthochromic CSF with high protein and normal cell count.
Equine Herpes Myeloencephalopathy . Xanthochromic
Virus isolation can be attempted on buffy coat samples, nasal swabs, and/or CSF in an attempt to identify the virus.
*xanthochromic = the yellow discoloration of cerebrospinal fluid (CSF) caused by hemoglobin catabolism
Equine Herpes Virus 3
Causes papules, pustules, and ulcers to the vestibular mucosa, vulvar skin, and the penis and prepuce (balanoposthitis). Less frequently, it can involve the skin of the face. There are no systemic signs or consequences of the infection, although secondary bacterial infections are possible. Spontaneous recovery usually occurs over about 2 weeks, and no treatment is usually required except sexual rest to prevent spread as balanoposthitis is venereally transmitted.
Equine Protozoal Myeloenchephalitis (or myelitis) (EPM) is caused by _____. This organism causes ____ areas of necrosis in the ____ and ____. Therefore clinical signs are often ___ and ___. The horse is usually bright and alert but demonstrates ____, weakness and muscle atrophy. Muscle atrophy often affects ____. It can affect ____ age horses.
Equine Protozoal Myeloenchephalitis (or myelitis) (EPM) is caused by Sarcocystis neurona. This organism causes multifocal areas of necrosis in the brain and spinal cord. Therefore clinical signs are often multifocal and asymmetric. The horse is usually bright and alert but demonstrates asymmetric ataxia, weakness and muscle atrophy. Muscle atrophy often affects the gluteal and quadriceps muscles. It can be seen as any age. Clinical signs include hyporeflexia, spasticity, localized areas of sweating, cerebellar signs, head tilt, facial paralysis, circling, dysphagia, and blindness. This will result in damage of both white and gray matter.
Equine Viral Arteritis
Venereal or aerosol - Nidovirales
Typical cases are characterized by fever, depression, anorexia, leukopenia, dependent edema (especially of the lower hind extremities, scrotum, and prepuce in the stallion), conjunctivitis, supra- or periorbital edema, nasal discharge, respiratory distress, skin rash, temporary subfertility in affected stallions, abortion, and infrequently, illness and death in young foals
Symptomatic treatment
Fistulous withers
inflammation of the supraspinous bursa. This bursa is variable in size and location but is usually found between the second and fifth thoracic vertebrae and can extend ventrolaterally to the margin of the scapular cartilage. The etiology is thought to be infectious. Clinical signs are pain, heat, and swelling in the region of the bursa. After days to weeks, the bursa can rupture resulting in draining of fluid. Brucella abortus has been identified in up to 80% of clinical cases by serology and culture. Treatment consists of flushing the fistula and appropriate antibiotics.
Fluid calculation
(deficit x BW) + maint (60 ml/kg/day)
Foal pneumonia can be caused by
Streptococcus zooepidemicus and Rhodococcus equi
Fracture of basilan bone in foal
Cranial nerves VII and VIII located on proximal boarder
Galvayne’s groove
appears at 9 years of age
Gasterophilus intestinalis is the horse ____ fly which can cause ____-itis due to the the attachment of larvae in the ____. There will also be eggs in on the horse’s ___ where the adults deposit them. Management consists of administering ____ twice per year, typically ____ and ___.
Gasterophilus intestinalis is the horse bot fly which can cause gastritis due to the the attachment of larvae in the stomach. There will also be eggs in on the horse’s front legs where the adults deposit them. Management consists of administering avermectins twice per year, typically early summer and again in fall.
Glanders
caused bacteria Burkholderia mallei and causes 3 different forms of disease; nasal glanders, pulmonary glanders, and cutaneous glanders (also referred to as Farcy)
Glanders - test
Mallein test
Glomerulonephritis
Treatment options: plasma transfusion, low protein diet, corticosteroids
Gonadal dysgenesis
Chromosomal abnormality, the mare would not have been able to have had a normal pregnancy previously.
congenital developmental disorder of the reproductive system characterized by a progressive loss of germ cells on the developing gonads of an embryo.
Grain overload treatment
goals of treatment are to prevent further development of laminitis, reduce pain, and reduce other complications from laminitis. Acute laminitis is considered a medical emergency and treatment should be initiated as soon as possible. Administer mineral oil by stomach tube acts as a laxative and decreases absorption of toxic material from the GI tracts. IV fluids, parenteral antimicrobials, anti-inflammatory drugs, hyperimmune serum or plasma. Place horse in stall with soft flooring. Other options include heparin, phenoxybenzamine, and heart-bar shoeing. Some practitioners recommend cold packs, but there is conflicting evidence that hot packs may be more beneficial.
Granulosa cell tumor
Usually, 1 ovary is large and the other small; unless there are bilateral tumors, which is uncommon. Causes aggression in mares due to increases levels of testotsterone.
Guttural pouch empyema
infection and accumulation of purulent material within the guttural pouch, usually secondary to strangles
Guttural pouch mycosis
Aspergillus nidulans, Cranial nerves 7, 9, 10, 11, & 12 all cross the medial pouch as well as the sympathetic trunk and internal carotid artery. The external carotid artery crosses the lateral pouch.
Guttural pouch tympany
air - Guttural pouch tympany is seen in horses ranging from birth to 1 yr of age and is more common in fillies than in colts
The affected guttural pouch is distended with air and forms a characteristic nonpainful swelling in the parotid region
Tympany may result from inflammation or malformation of the pharyngeal orifice of the eustachian tube, which then acts as a one-way valve by allowing air to enter the pouch but preventing its return into the pharynx
Habronema muscae
internal stomach parasite
Treat with Ivermectin
Habronemiasis
Larvae of the stomach worm that emerge from flies feeding on pre-existing wounds or genitalia or eyes, then migrate into the tissue and cause a granulomatous reaction. Inside the granulomas, you can find dead larvae. Bigger problem in cattle but can occur in horses and typically creates nodules on the back that have a pore on top.
Haematobia irritansa
Bigger problem in cattle, but can affect horses especially if cattle are nearby. Ventral midline dermatitis with wheals with a central crust the progress to alopecia and ulceration with fairly focal lesions.
Hyperammonemia
Associated with intestinal disease in horses. Exact cause of neurologic signs and disease process is unknown, bit it is presumed to result from excessive ammonia production within the intestinal tract. This overwhelms the ability of the liver to metabolize ammonia, and subsequently causes the development of encephalopathic signs.
Lawsonians
in foals - equine proliferative enteropathy
L. intracellularis infections cause diarrhea, depression, fever, inappetance (anorexia), weight loss, edema (fluid swelling) on the abdomen or lower limbs, a poor hair coat, and intermittent colic due to thickening of mucosal lining in the small and large intestine. While any age of horse can be infected, weanling foals 4 to 7 months old are most susceptible
Fecal PCR to confirm
Treat with erythromycin or tetracyline
Length of estrous cycle
19-26 days
Length of estrus
2-10 days, but on average 6 days
Leukoencephalomalacia
fumonisin toxicity…
Limb contracture correction
Distal check desmotomy relieves the deep digital flexor contracture while proximal check desmotomy relieves superficial digital flexor contracture. I the contracture is severe, it may recur 2-4 months after surgery. As such time, a suspensory desmotomy is an option but subluxation at the proximal interphalangeal joint is a common consequence.
Mare Reproductive Loss Syndrome
caused by Eastern tent caterpillars
Maxillary sinusitis
generally due to tooth root abcess
Myotonia
inability to relax voluntary muscle after vigorous effort “dive bomber” sound on EMG -
The ‘dive bomber’ sound heard on EMG is produced by repetitive firing after contraction of affected muscle fibers and is essentially pathognomic for myotonia.
Nasal glanders
presents with high fever, loss of appetite and labored breathing with cough. VIscour mucopurulent discharge or crusting may present around the nares. There may be ulceration of the upper respiratory passages that resolve in the form of star-shaped cicatrices (“stellate scars”). Regional lymph nodes may be enlarged and indurated and may rupture or adhere to deeper tissues.
Neonatal Isoerythramlysis antigens
Aa & Qa
What lesions are see with Onchocerca (Onchocera cervicalis equine)
Cause non-seasonal, non-pruritic dermatitis and uveitis in horses due to hypersensitivity to dying microfilariae. Lesions include alopecia and scaling of the ventral midline, face and pectoral region, often diamond-shaped and may have a “bull’s eye” lesion on the top of the head. Not pruritic. Ocular lesions can occur; uveitis, conjunctivitis, and keratitis. Uveitis is caused by aberrant migration of the microfilariae; when they die, an inflammatory response is generated. Ivermectin is used to treat the larvae.
Oxyuris equi
pin worm, infest the perineal region and results in perineal irritation after eggs are laid. A frequent diagnostic test performed when visualizing damaged perineal regions is a scotch tape preparation.
Paranoplocephala mamillana
Tapeworm usually found in small intestine
Treat with Praziquantel
Parascaris equoum causes colic due to _____
causes intestinal impaction in foals (concern of perforation), can cause diarrhea, lethargy, depression, and respiratory signs (migrates through lungs). Diagnosis by demonstration of eggs in the feces.
Pemphigus foliaceus
autoimmune skin disease which results in vesicles, erosions and ulcerations, especially around mucocutaneous junctions.
Autoimmune disease in which antibodies are formed against the intercellular adhesin proteins. In horses, this disease causes crusting lesions of the head, limbs, and ventrum. Definitive diagnosis is found on biopsy of the skin showing acantholysis. There are two forms of the disease in horses. The juvenile form may result in spontaneous remission and carries a good prognosis. The adult form of the disease carriers a worse prognosis.
Peroneus tertius rupture
allows extension of the hock while the stifle is flexed, which means that as the limb moves forward, the hock joint does not flex. The horse will usually bear weight and pain is not a feature.
Persistent corpus luteum
Progesterone made by the corpus luteum prevents estrus. There will be follicles in the ovaries, and the horse may still ovulate but is non-receptive to stallions. The corpus luteum is usually not palpable.
Persistent superficial and deep digital flexor tendon contracture treatment
Distal check desmotomy and proximal check desmotomy. The distal check desmotomy relieves the deep digital flexor contracture while proximal check desmotomy relieves superficial digital flexor contracture. If the contracture is severe, it may recur 2-4 months after the surgery. At such time, a suspensory desmotomy is an option but subluxation at the proximal interphalangeal joint is a common consequence.
Pigment nephropathy
Occurs as a result of myositis (tying up). Nephrosis and subsequent renal failure is caused by large amounts of myoglobin being filtered by the kidney. This usually occurs in horses that have been subjected to extreme conditions such that the animal breaks down a substantial amount of muscle. The same condition can occur with intravascular hemolysis.
Potomac Horse Fever
Gram-negative bacterium Neorickettsii risticii. Disease usually occurs in the summer. High fever, diarrhea, and presence of laminitis. Dehydration and profound leukopenia. Treat with oxytetracycline. Diagnose with PCR (takes several days - treat empirically until results come through)
Pregnancy check at 30 days
Palpate for chorionic vesicle
Psoroptes
Clinical signs: pruritus of the ear, head shaking. Diagnosis from skin scrape and otoscopic exam. Psoroptic mange is a reportable disease.
Pulmonary glanders
The pulmonary form often develops over several months, beginning as a fever with dyspnea and cough. Lung lesions commence as light colored nodules surrounded by hemorrhage or as diffuse pneumonia. The nodules may become caseous or calcified and discharge contents to the upper respiratory tract. Nodules may also be found in other organs.
Purpura hemorrhagica
complications of strangles, occurs weeks after infection or can occur after a bacterin is given. Exact reason why some horses develop purpura is unknown.
caused by bleeding from capillaries which results in red spots on the skin and mucous membranes together with oedema (swelling) of the limbs and the head.[1] Purpura hemorrhagica is more common in younger animals
The liver histopathologic changes associated with Pyrrolizidine alkaloid toxicity are:
megalocytosis, periportal fibrosis, and biliary hyperplasia
Senecio sp, Crotolaria sp and Heliotropium sp contain _____. When a horse ingests this compoud, it is metabolized to ____ in the liver which _____ and cause a _____ effect. Since hepatocytes cannot ____ due to the toxin, ____ form and subsequently _____. Clinical signs include weight loss, icterus and photosensitization.
Senecio sp, Crotolaria sp and Heliotropium sp contain pyrrolizidine alkaloids. When a horse ingests this compoud, it is metabolized to pyrroles in the liver which cross link DNA and cause an anti-mitotic effect. Since hepatocytes cannot divide due to the toxin, megalocytes form and subsequently die and are replaced by fibrosis. Clinical signs include weight loss, icterus and photosensitization
Quittor refers to an infection of the ____ associated with the bone _____
An infection of the alar cartilage of P3
Retained placenta
>3 hours
Rift Valley Fever
viral disease primarily of ruminants causing influenza-like signs and hepatic lesions
Rodoccocus equi is the most common cause of pnuemonia in foals ____. The characterized lesion is ____ noted on ____. The clinical presentation is typically ____ and characterized by _____. The treatment is ____ plus ____. Complications include _____. Prevention invovles _____.
Rhodococcus equi (gram-positive) is the most common cause of pnuemonia in foals from 1-6 months of age. The characteristic lesion is pulmonary abscess formation that may be noticed on thoracic ultrasound. On U/S you should notice the capsular structure with an anechoic center which represents a fluid-filled abscess. The presentation is typically a slow insidious onset characterized by some or all the following signs: weight loss, fever, cough, nasal discharge, increased respiratory effort, and ill-thrift. The treatmetn is a macrolide (erythromycin, clarithromycin, azithromycin - gram positive ribosomal protein synthesis inhibitor) and rifampin. Possible complications include internal abscesscation, osteomyelitis and septic arthritis. Prevention involves limiting exposure to dusty environments and administration of hyperimmunized plasma.
Rupture of Achilles tendon in horse
Gastrocnemius + superficial flexor tendon rupture
just gastrocnemius would drop the hock and curl the toe, both drop the hock.
Salmonella in horses causes ____ and is treated via ____
causes diarrhea and leukopenia, occurs at any time of the year. Several clinical presentations including subclinical infection, self-limiting diarrhea, and acute diarrhea. Diagnosis requires serial cultures of feces 3-5 days.
Supportive care with fluids and electrolytes replacement
What parasite is shown and how is it treated?
Strongyloides westeri egg is shown, it is transmitted to foals through mare’s milk, treat the post-partum mare with ivermectin. Associated with diarrhea in foals but not adults. Diagnosis by demonstration of eggs in the feces
cause of foal heat diarrhea and can migrate through the lung causing damage
This image depicts the _____ block which desensitizes ____
palmar nerve block; desensitizes 50-70% of the palmar/plantar aspect of the foot including most of the distal interphalangeal (coffin) joint and the entire sole.
What block is this?
Palmar digital
The needle is in the ____ joint
fetlock
The needle is in the _____ joint
pastern
The image shows the ____ block which desensitizes the _____ and can be used for _______
Abaxial sesamoid block; desensitizes skin over the palmar pastern and distal dorsal pastern along with the foot and
proximal interphalangeal (pastern) joint are desensitized. Partial desensitization of the palmar fetlock (carpometacarpal/tarsometatarsal) may
also occur. Can be used for laminitis.
The image depicts the _____ block which desensitizes the _______
Low four-point block (palmar/plantar); desensitizes entire metacarpophalangeal (fetlock) joint and structures distal to this joint.
Melanomas occur in up to ____% of gray horses. They typically occur on the ____ and ____. ___ is not involved in the development of equine melanomas, as opposed to in humans. Treatment involves surgery or ____.
Melanomas occur in up to 80% of gray horses. They typically occur on the perineum and tail base. UV light is not involved in the development of equine melanomas, as opposed to in humans.Treatment involves surgery or cryosurgery.
The ability to flex the stifle while extending the hock indicates rupture of the _____
peroneus tertius
____ is a lay term for cunean bursitis
Jack spavin
What parasite is this egg found in a foal fecal? (~100um)
parascaris equorum
What is this and how do you prevent it?
Strongylus vulgaris; ivermectin
___ are the cause of “summer sores” in horses. The adult worms live in the _____ but don’t cause signs there.
Habronema cause summer sores (Granulomatour dermal lesions). Adults live in the stomach but don’t cause signs there. Treat with ivermectin.
