BCSE 20 Days Fot Test Day Flashcards
Which two drugs are BOTH contraindicated for use as injectable antibiotics in pigs?
Tilmicosin, Chloramphenicol
Lincomycin, Procaine Penicillin G
Tilmicosin, Lincomycin
Lincomycin, Oxytetracycline
Chloramphenicol, Oxytetracycline
Answer: Tilmicosin, Chloramphenicol
Chloramphenicol has been associated with bone marrow suppression/aplastic anemia in exposed humans, and is BANNED IN FOOD ANIMALS.
Tilmicosin (Micotil®) is a macrolide contraindicated in pigs (injection may kill them. May kill YOU too). Remember that tilmicosin should not be used in an automatically powered syringe because an accidental self-injection can be FATAL to humans.
Tilmicosin IS approved for use a s a feed additive in swine.
Which of the following suture patterns would be appropriate to secure a drain to the body wall (for example, for indwelling thoracic drainage)?
Ford interlocking
Aberdeen knot
Purse string
Finger-trap
Gambee
Answer: Finger-trap
The finger-trap technique or a double-clove hitch pattern is used to secure a drain to the body wall. These sutures tighten circumferentially if the tube is pulled on, so it works well to keep the drain in place.
This website from the University of Guelph Vet Surgery Online has a nice video showing the finger-trap suture.
The Gambee and Ford interlocking are appositional patterns. A purse string is used to make an orifice smaller (such as for rectal prolapse). The Aberdeen knot is used at the end of a continuous line of suture.
Synthetic pheromones are used to treat feline elimination disorders. Which one of the following types of pheromones do they mimic in the cat?
Facial
Urine
Mammary
Paw
Anal gland
Answer: Facial
Facial pheromones are thought to act at the level of the hypothalamus to decrease anxiety and effectively decrease urine spraying. Feliway ® and Felifriend ® are brand names of products containing synthetic feline facial hormones.
Some cats may not respond well to pheromones or develop worsening behavior. The best results have been seen when the underlying anxiety disorder is treated with management changes, behavior modification, and medication.
Which of the following accurately describes proper storage of an unstained blood smear prior to staining and evaluation?
Keep in cabinet with formalin to allow slight cellular preservation
Store at room temperature, stain within 48 hours
Slides cannot be stored unstained due to immediate alterations in cellular appearance
Heat-fix the slide and then keep it in the freezer
Should be kept in refrigerator
Answer: Store at room temperature, stain within 48 hours
Blood smears should be kept at room temperature and must be stained within 48 hours or else there is inadequate staining. Ideally should be stained within several hours to minimize artifacts in red blood cell appearances.
Blood smears are prepared to confirm cell counts, evaluate cellular morphology, and look for infectious agents or neoplasia.
Check out this video on how to evaluate a blood smear, courtesy of Vet Clinpath.
Unstained slides should be stored at room temperature because condensation in the refrigerator or freezer damages cells. They should also be stored away from formalin because exposure to formalin inhibits appropriate staining.
https://eclinpath.com/hematology/hemogram-basics/blood-smear-examination/
https://youtu.be/wIZtvTGJL6M?si=gvlyLPXovgrXe9os
Stationary anode radiology machines are used for which one of the following kinds of procedure?
Contrast studies
Computerized tomography (CT)
Magnetic resonance imaging (MRI)
Fluoroscopy
Dental imaging
Answer: Dental imaging
Stationary anodes are used primarily in dental units as well as in portable machines used for large animals.
Stationary anode units have a smaller capacity for x-ray production compared to rotating anodes. They are not practical for most larger body parts because they cannot produce strong enough x-ray beams to penetrate them.
Cats have how many permanent teeth?
40
26
30
32
42
Answer: 30.
In cats there are 30 permanent teeth and 26 deciduous (baby) teeth. Ruminants have 32. Dogs have 42 permanent teeth. Food-loving pigs have the most teeth at 44. Horses vary between 36-44.
Here is a diagram of cat permanent dentition from the Royal Veterinary College and a dental formula table for large and small animals.
Refs: Bassert, Beal, and Samples, McCurnin’s Clinical Textbook for Veterinary Technicians, 9th ed., p. 1117.
https://www.merckvetmanual.com/digestive-system/dental-development-and-anatomy/dental-development-in-animals?autoredirectid=14174
Which one of the following choices most correctly describes the acid-base status of patients with diabetic ketoacidosis (DKA)?
High anion gap metabolic acidosis
Strong ion respiratory acidosis
Hyperchloremic non-anion gap acidosis
Normal anion gap metabolic acidosis
Mixed respiratory and metabolic acidosis
Answer: High anion gap metabolic acidosis
A high anion gap metabolic acidosis occurs in diabetic ketoacidosis (DKA) due to increased ketones and lactic acid/lactate.
Anion gap = (Na + K) - (HCO3 + CI)
Anion gap is a way to assess the difference between unmeasured cations and unmeasured anions in the blood. Ketones and lactate are both examples of unmeasured anions so an increase in either can result in an increased anion gap (as seen in DKA).
Lactic acid/lactate is a byproduct of anaerobic metabolism that develops due to dehydration/hypovolemia and poor perfusion.
Visit the Cornell University eClinPath website for more info on acid-base status and ketosis.
https://www.merckvetmanual.com/emergency-medicine-and-critical-care/monitoring-the-critically-ill-small-animal/monitoring-the-critically-ill-small-animal-using-the-rule-of-20
Which part of the camelid GI tract secretes hydrochloric acid and is most similar to a monogastric animal’s stomach?
Glandular portion of the duodenum
Caudal 20% of third compartment
Ventral half of second compartment
Cranial sac of first compartment
Abomasum
Answer: Caudal 20% of third compartment
Gastric glands in the caudal 20% of the third compartment (C3) of camelids, which most closely resembles a monogastric animal’s stomach, secrete hydrochloric acid and proteases.
Camelids rely on their forestomach for microbial digestion, much like ruminants. They have three compartments - the first two (C1 and C2) make up 10-15% of an adults camelid’s body weight and occupy over 50% of the space in the abdomen. Fermentative digestion occurs both here and in the cranial 80% of the smaller third compartment.
Click here to see a diagram of camelid digestive anatomy.
C1 is divided into cranial and caudal sacs by a large transverse pillar. C1 and C2 are lined by stratified squamous mucosa and C1 contains glandular saccules while C2 contains glandular cells. These specialized structures facilitate rapid absorption of water, electrolytes, and VAs similar to the function of papillae of the ruminant rumen. It is not well understood how these saccules facilitate absorption so efficiently.
The remainder of the camelid Gl tract is similar to ruminants - small intestine, relatively small cecum, ascending colon with spiral loops (centripetal and centrifugal portions), transverse colon with smaller spiral loops, and descending colon to the rectum.
Sodium phosphate-containing enemas are specifically contraindicated in which group?
Animals with megacolon
Geriatric animals
Cats
Pot-belly pigs
Dogs weighing more than 20 kg
Answer: Cats
Enemas containing sodium phosphate (like Fleet® enemas, a human product) are contraindicated in cats and small dogs because they can cause severe hyperphosphatemia and subsequent hypocalcemia.
Avoid administration of phosphate-containing enemas to:
Cats
Small dogs (under 10 kg)
Patients with severe obstipation or compromise of the colonic wall
Patients with compromised renal function
Patients with hypernatremia, hyperphosphatemia, or hypocalcemia
Also, do not administer more than two per 24-hour period to neonatal foals for the same reasons.
Sodium biphosphate or sodium phosphate enemas are hyperosmotic cathartics that draw fluid into the intestine by osmosis.
https://www.merckvetmanual.com/pharmacology/systemic-pharmacotherapeutics-of-the-digestive-system/cathartic-and-laxative-drugs-used-in-monogastric-animals?autoredirectid=21576
What is the purpose of a curette?
Cauterize blood vessels
Highly absorbent surgical sponge
Hold intramedullary bone pins
Scrape hard tissues
Answer: Scrape hard tissues
A curette is like a tiny, sharp ice-cream scooper, used to scrape hard tissues like bone or cartilage.
Curettes are also often used to retrieve cancellous bone from a medullary bone cavity (like in the tibia, humerus or ilium of the pelvis) for a bone graft to help in fracture repair.
What is the purpose of a curette?
Cauterize blood vessels
Highly absorbent surgical sponge
Hold intramedullary bone pins
Scrape hard tissues
Answer: Scrape hard tissues
A curette is like a tiny, sharp ice-cream scooper, used to scrape hard tissues like bone or cartilage. Curettes are also often used to retrieve cancellous bone from a medullary bone cavity (like in the tibia, humerus or ilium of the pelvis) for a bone graft to help in fracture repair.
Which group can all cause cardiomyopathy in ruminants?
Vitamin E deficiency, Claviceps spp., arsenic
Cassia occidentalis (coffee senna), lead, amprolium
Lasalocid, polioencephalomalacia, copper toxicity
Gossypol (cottonseed), lymphosarcoma, monensin
Clenbuterol, sarcocystis, aflatoxin
Answer: Gossypol (cottonseed, lymphosarcoma, monensin.
Cardiomyopathy in cattle is caused by gossypol (cottonseed), lymphosarcoma, and monensin (as well as lasalocid-both are ionophore feed additives).
In addition, can see cardiomyopathy with selenium/vitamin E deficiency. (white muscle disease), copper deficiency (myocardial fibrosis) and Cassia poisoning (coffee senna).
Link: Gossypol Poisoning in Animals
https://www.merckvetmanual.com/toxicology/gossypol-poisoning/gossypol-poisoning-in-animals?mredirectid=948
Link: Bovine Leukosis
https://www.merckvetmanual.com/generalized-conditions/bovine-leukosis/bovine-leukosis?autoredirectid=20435
Link: Nutritional Myopathies in Ruminants
https://www.merckvetmanual.com/musculoskeletal-system/myopathies-in-ruminants-and-pigs/nutritional-myopathies-in-ruminants-and-pigs
The organism shown under magnification below was found on a cat’s fur. What is it?
Answer: Cheyletiella
Link: Mange in Dogs and Cats
https://www.merckvetmanual.com/integumentary-system/mange/mange-in-dogs-and-cats?redirectid=24977
This is the clinical and cytologic appearance of blastomycosis, a common fungal disease of dogs in the river valleys of the central United States. Young, male, large-breed dogs are most commonly affected. Blastomycosis typically presents with respiratory signs, fever, lameness, peripheral lymphadenopathy, skin lesions, and ocular disease.
Cytology reveals 8-25 micrometer, thick-walled, basophilic, round/ovoid structures with refractile, double-contoured walls and surrounding intense inflammatory infiltrate.
Histoplasmosis is a primary differential diagnosis, presenting similarly but with smaller organisms (1-4 micrometers) and chronic diarrhea.
Coccidioidomycosis is another differential in dogs from the arid Southwestern U.S., Mexico, and Central America. Aspergillosis and cryptococcosis are also possible differentials, each with distinct presentations and organism characteristics.
A two-year-old male neutered Irish setter from the Ohio river valley basin is presented with a six-week history of coughing, weight loss and lethargy. Exam reveals peripheral lymphadenopathy and multiple draining cutaneous nodules. Cytology from a smear of an aspirated skin nodule is shown below. Cytology reveals 8-25 micrometer, thick-walled, basophilic, round/ovoid structures with refractile, double-contoured walls and surrounding intense inflammatory infiltrate.
What is the diagnosis?
Answer: Blastomycosis
This is the clinical and cytologic appearance of blastomycosis a common fungal disease of dogs from the river valleys of the central United States. Young, male, large-breed dogs are most commonly affected.
Blastomycosis typically presents with respiratory signs, also look for fever, lameness, peripheral lymphadenopathy, skin lesions, and ocular disease. 85% of cases have pulmonary involvement. Look for blastomyces organisms on cytology of draining cutaneous nodules. Organisms are typically round - ovoid, pale pink, and have a double-contoured wall with broad-based budding.
Histoplasmosis is the primary DDX. Histoplasmosis has a similar distribution in the river valleys of the central United States.
Dogs with histoplasmosis typically present with chronic diarrhea, weight loss, and respiratory signs; cats typically present with respiratory signs. Note that histoplasma organisms are much smaller (1-4 micrometers for histo vs. 8-25 micrometers for blasto), and unlike blasto, they are difficult to detect with routine H&E stain. Use fungal-specific stains to identify histoplasma yeast forms in phagocytes. Look for small yeast organisms that may show narrow-based budding with a thin cell wall and a thin, clear zone between the cell wall and cytoplasm.
Think of coccidioidomycosis in dogs from the arid and semiarid Southwestern U.S., Mexico, and Central America (think dusty desert). Spores are carried on dust and inhaled. Epidemics may occur after dust storms or excavation.
Organisms are difficult to identify on cytology and are typically identified on histopathology. Organisms vary in size (20-80 micrometers to 200 micrometers) and appears as spherules with a double-contoured wall. Mature organisms contain tiny endospores (sporangiospores) 2-5 micrometers in diameter.
Because it is ubiquitous, positive culture results for Aspergillus should be supported by demonstration of narrow, hyaline, septate, branching hyphae in tissues. Usually a nasal presentation in dogs.
Disseminated aspergillosis is seen most commonly in female
German shepherds.
Think of cryptococcosis in cats with granulomatous rhinitis and sinusitis. In cats look for a swollen “roman nose” appearance. Seen in other species (cows, dogs) with varying presentations.
Link: Blastomycosis in animals
https://www.merckvetmanual.com/generalized-conditions/fungal-infections/blastomycosis-in-animals?autoredirectid=21098
Link: Histoplasmosis in Animals
https://www.merckvetmanual.com/generalized-conditions/fungal-infections/histoplasmosis-in-animals?autoredirectid=21090
Link: Coccidioidomycosis in Animals
https://www.merckvetmanual.com/generalized-conditions/fungal-infections/coccidioidomycosis-in-animals?autoredirectid=21094
Link: Aspergillosis in Animals
https://www.merckvetmanual.com/generalized-conditions/fungal-infections/aspergillosis-in-animals?autoredirectid=21102
Link: Cryptococcosis in Animals
https://www.merckvetmanual.com/generalized-conditions/fungal-infections/cryptococcosis-in-animals?autoredirectid=21100
What is the function of dermatophyte test media?
Answer: identifies fungal pathogens
Dermatophyte test media (DTM) is used to identify fungal pathogens like ringworm.
A few hairs are plucked from the affected area and incubated in DTM.
Fungal cultures usually grow slowly and at room temperature, so results will not be known for a few days or up to two weeks.
DTM cultures should be incubated in a darkened area, such as inside a closed cabinet or drawer. If the culture is positive for fungi, the DTM media changes color.
Which one of the following choices is most likely to confirm diagnosis of salmonellosis in pigs?
Answer: Culture cut surface of mesenteric lymph node
Salmonellae is most reliably isolated from enlarged mesenteric lymph nodes in pigs. Mucosae and feces may also be successfully cultured.
The cut surface of an enlarged lymph node is streaked directly on a selective medium like brilliant green agar or by inoculation of enrichment media.
Histologic exam of affected intestine and liver is a valuable adjunct test to distinguish salmonellosis from two other hemorrhagic diarrheal diseases of grower pigs - proliferative enteritis and swine dysentery.
Link: Intestinal Salmonellosis in Pig
https://www.merckvetmanual.com/digestive-system/intestinal-diseases-in-pigs/intestinal-salmonellosis-in-pig
Link: Porcine Proliferative Enteropathy
https://www.merckvetmanual.com/digestive-system/intestinal-diseases-in-pigs/porcine-proliferative-enteropathy?autoredirectid=16618
Link: Swine Dysentery
https://www.merckvetmanual.com/digestive-system/intestinal-diseases-in-pigs/swine-dysentery
A birnavirus causes which one of these avian diseases?
Answer: Infectious bursal disease
Infectious bursal disease (IBD) is caused by a birnavirus.
Click here to see an enlarged, balloon-like hemorrhagic bursa of Fabricius, characteristic of IBD.
IBD is shed in feces and transferred barn to barn via fomites. Very stable. Difficult to eradicate from premises.
Signs include clinical picture given above in older birds, or MORE IMPORTANT subclinical form in young birds, which causes immunosuppression via destruction of immature lymphocytes in bursa, thymus, spleen.
Immunosuppressed birds do not respond well to vaccination and are predisposed to infections with normally nonpathogenic viruses and bacteria.
Common diseases usually exacerbated by IBDV infections. See large economic losses.
Ref: The Merck Veterinary Manual online edition.
A routine CBC, serum biochemistry panel, and urinalysis are ordered on a 12-year-old female spayed Shi Tzu who has been lethargic with poor appetite for several days. She is not used to leaving the house and was very stressed during the exam. The BUN and creatinine are mildly increased, the glucose is moderately increased, and the urine specific gravity is low. What could be causing these laboratory abnormalities?
Answer: Renal disease
Azotemia (increased BUN and creatinine) in the face of a decreased or normal urine specific gravity indicates renal disease.
In a dehydrated animal with azotemia, the urine should be more concentrated as the kidneys try to maintain hydration.
Stress and excitement can increase serum glucose. To help determine if the hyperglycemia is clinically significant, the test can be repeated when the animal is calm.
Alternatively, serum fructosamine levels can be measured.
What is a male pig called when it is castrated before puberty?
Answer: Barrow.
A male pig castrated before puberty is called a barrow. A boar is an intact male pig.
A young female pig that has not had a litter yet is called a gilt. A sow is an adult female pig that has had a litter of piglets.
A wether is a castrated male sheep, while a ram is an intact male sheep. A ewe is a female sheep.
A female ferret is called a jill and a male is called a hob.
A horse is presented with a dropped fetlock and the toe is lifted off the ground. Which structure has most likely been significantly damaged/ severed?
Answer: Deep digital flexor tendon.
Significant injury to the deep digital flexor tendon (DDFT) leads to a dropped fetlock with the toe lifted off the ground because the DDFT inserts on the palmar/plantar/solar surface of the third phalanx.
Rupture or severing of the superficial digital flexor tendon leads to a dropped fetlock with no change in toe position because it inserts on the distal aspect of the proximal phalanx and the proximal aspect of the second phalanx.
Damage to both branches of the suspensory ligament would lead to a dropped fetlock with the toe on the ground.
The impar ligament runs between the distal border of the navicular bone and the palmar/plantar surface of the third phalanx. Damage to it would not cause a dropped fetlock.
Link: Equine Trauma and First Aid
https://www.merckvetmanual.com/emergency-medicine-and-critical-care/equine-emergency-medicine/equine-trauma-and-first-aid
An adult horse is presented for moderate colic of a couple hours’ duration. After a thorough physical exam, the horse is sedated to facilitate abdominal palpation per rectum and passage of a nasogastric tube. The clients asks, “Doc, why do you always have to pass a tube when a horse colics?” and you respond “Well, horses cannot vomit and it’s a good way to rehydrate them…” Why can’t horses vomit?
Answer: Strong lower esophageal sphincter
Horses cannot vomit for a variety of reasons, including a very strong lower esophageal sphincter, the low location of the entrance of the esophagus into the stomach at the cardia (so a distended stomach really clamps it down), and poorly developed neural pathways for vomiting.
In rare cases of severe gastric distention (typically near death) food can be regurgitated up and out. Remember that regurgitation is the passive movement of food up and out of the stomach vs. vomiting is an active, forceful expulsion of gastric contents.
The equine stomach typically only holds about 8-10 L of contents, though can stretch to 20-25 when maximally distended. Gastric dilatation, rupture, and death can occur with gastric impactions (less common) or conditions that prevent the aboral movement of ingesta through the small intestine (more common). Thus, the passage of a nasogastric tube into the stomach is an important component of every colic examination to rule out gastric dilatation (and to administer fluids and therapy!).
Link: Overview of Colic in Horses
https://www.merckvetmanual.com/digestive-system/colic-in-horses/overview-of-colic-in-horses
An adult horse is presented for moderate colic of a couple hours’ duration. After a thorough physical exam, the horse is sedated to facilitate abdominal palpation per rectum and passage of a nasogastric tube. The clients asks, “Doc, why do you always have to pass a tube when a horse colics?” and you respond “Well, horses cannot vomit and it’s a good way to rehydrate them…” Why can’t horses vomit?
Answer: Strong lower esophageal sphincter
Horses cannot vomit for a variety of reasons, including a very strong lower esophageal sphincter, the low location of the entrance of the esophagus into the stomach at the cardia (so a distended stomach really clamps it down), and poorly developed neural pathways for vomiting.
In rare cases of severe gastric distention (typically near death) food can be regurgitated up and out. Remember that regurgitation is the passive movement of food up and out of the stomach vs. vomiting is an active, forceful expulsion of gastric contents.
The equine stomach typically only holds about 8-10 L of contents, though can stretch to 20-25 when maximally distended. Gastric dilatation, rupture, and death can occur with gastric impactions (less common) or conditions that prevent the aboral movement of ingesta through the small intestine (more common). Thus, the passage of a nasogastric tube into the stomach is an important component of every colic examination to rule out gastric dilatation (and to administer fluids and therapy!).
Link: Overview of Colic in Horses
https://www.merckvetmanual.com/digestive-system/colic-in-horses/overview-of-colic-in-horses
Which of the following complications can occur due to hypothermia during the anesthetic and post-anesthetic periods?
Hight gastrointestinal motility
Lower gastric pH
Increased nausea
Delayed drug metabolism
Excessive upper airway secretions
Answer: Delayed drug metabolism.
Hypothermia, typically defined as a body temperature less than 98°F (37°C), causes delayed drug metabolism and prolonged recovery.
Expect anesthesia-induced hypothermia, particularly with small animal patients. Take steps to reduce heat loss and maintain body temperature, such as avoiding excessive wetting of fur, limiting contact with cold surfaces, and providing heat support such as circulating warm water blankets.
Monitor body temperature every 15-30 minutes during anesthesia and in the post- anesthetic period until normothermia is reached.
Ref: Bassert, Beal and Samples, McCurnin’s Clinical Textbook for Veterinary Technicians, 10th ed., p. 952.
What kind of cell is indicated by arrow?
Band neutrophil
Foamy macrophage
Platelet
Activated lymphocyte
Basophil
Answer: Band neutrophil
This is a band neutrophil with its distinctive curved or U-shaped nucleus.
Band neutrophils are immature cells that were released prematurely into circulation due to overwhelming demand. The presence of many band neutrophils in circulation is called a “left shift.” It indicates significant inflammation or infection within the body.
For more info and images, see the Cornell Clin Path website: Neutrophils, Normal leukocytes.
Refs: Bacha and Bacha, Color Atlas of Veterinary Histology, 3rd ed. Image courtesy of Dr. Seth Chapman. Bassert, Beal and Samples, McCurnin’s Clinical Textbook for Veterinary Technicians, gthed, pp. 383.
What part keeps exhaled gasses moving away from the patient in a circular rebreathing anesthetic delivery system?
Answer: One-way valves help direct gas flow. Expired gasses pass through a CO2 scavenger canister to remove CO2.
STRATEGY HINT: See how the word “valve” occurs in 3 choices? Chances are that the correct answer contains this word.
In a circular rebreathing anesthetic system, one-way valves are crucial for directing the flow of gases, ensuring that exhaled gases move away from the patient. These gases pass through a CO2 scavenger canister, effectively removing carbon dioxide, thereby maintaining a clear pathway for fresh gas to reach the patient while preventing rebreathing of expired gases. This system optimizes the efficiency and safety of anesthesia delivery.
A four-year-old beef cow in East Africa is presented with weight loss, intermittent fever, and pale mucous membranes. The top differential diagnosis in the case is trypanosomiasis. What vector transmits this disease in sub-Saharan Africa?
Answer: Tsetse fly.
The tsetse fly transmits protozoa in the genus Trypanosomas to a variety of animal species. The fly resides only in sub-Saharan Africa thus trypanosomiasis is seen only in this region.
Use environmental insecticides and/or topical insecticides to control the tsetse fly population and reduce disease prevalence.
Mosquitoes and biting midges are important vectors for viral diseases world-wide. Ticks transmit protozoal diseases such as anaplasmosis and theileriosis.
T. congolense is the most common species to affect cattle but trypanosomiasis affects all mammals (including humans). There is no available vaccine for any trypanosoma species.
Link: Trypanosomiasis in Animals
https://www.merckvetmanual.com/circulatory-system/blood-parasites/trypanosomiasis-in-animals
A 15-year-old Quarter horse mare is presented for right front lameness grade 3/5 on the AAEP lameness scale (lameness consistently visible at the trot). She becomes sound after an abaxial nerve block. Radiographs of the distal limb look like this: What is the top differential diagnosis?
Exostosis of the second metacarpal
High ringbone
Pedal osteitis
Chronic proliferative synovitis
Spavin
Answer: High ringbone
This is an example of high ringbone (periostitis & osteoarthritis of the proximal interphalangeal joint leading to exostoses).
Very common in horses. Can be due to chronic wear and tear, overuse, or secondary to a traumatic episode.
Radiograph of arthrodesis of the proximal interphalangeal joint to resolve high ringbone.
Osselets are traumatic arthritides of the metacarpophalangeal joints.
Pedal osteitis is demineralization of the solar margin of the distal phalanx, usually due to inflammation.
Bone spavin is osteoarthritis of the distal intertarsal, tarsometarsal, and less commonly, the proximal intertarsal joints.
Ref: Pasquini and Spurgeon’s Anatomy Dom An 11t ed. pp. 88, 100.
Link: Osteoarthritis of the Proximal Interphalangeal Joint in Horses
https://www.merckvetmanual.com/musculoskeletal-system/lameness-in-horses/osteoarthritis-of-the-proximal-interphalangeal-joint-in-horses
Link: Pedal Osteitis in Horses
https://www.merckvetmanual.com/musculoskeletal-system/lameness-in-horses/pedal-osteitis-in-horses
Link: Osteoarthritis of the Distal Tarsal Joints in Horses
https://www.merckvetmanual.com/musculoskeletal-system/lameness-in-horses/osteoarthritis-of-the-distal-tarsal-joints-in-horses
Link: Lameness Exams Evaluating the Lame Horse
https://aaep.org/horsehealth/lameness-exams-evaluating-lame-horse
Which one of the following choices is the most common cause of enamel hypoplasia in cattle?
Hypermagnesemia
Copper toxicosis
Fluorosis
Distemper virus
Fescue poisoning
Answer: Fluorosis.
Chronic excessive ingestion of fluoride by cattle during the critical periods of tooth development, amelogenesis (enamel formation) and dentinogenesis (dentin formation) causes enamel hypoplasia. Exposure to excessive fluoride after teeth are fully formed does not result in dental lesions.
Dental fluorosis is commonly diagnosed by examining the incisiors, although all teeth may be affected. Dental lesions observed: staining, mottling, excessive erosion, hypoplasia, hypocalcification.
Osteofluorosis and lameness may also be observed.
Refs: Gibbons, Bov Med & SX, p. 288-300.
Link: Congenital and Inherited Anomalies of the Teeth
https://www.merckvetmanual.com/digestive-system/congenital-and-inherited-anomalies-of-the-digestive-system/congenital-and-inherited-anomalies-of-the-teeth
Congenital and Inherited Anomalies of the Teeth in Animals
1. Diseases:
• Anodontia, Hypodontia, Oligodontia: Missing teeth.
• Hyperdontia (Polyodontia): Extra teeth.
• Retained Deciduous Teeth: Persistence of baby teeth.
• Tooth Displacement/Rotation: Misaligned teeth.
• Enamel Hypoplasia, Hypomineralization, Dysplasia: Defects in enamel formation.
2. Symptoms and Clinical Presentations:
• Malocclusion, Crowding: Difficulty eating, weight loss.
• Discomfort: Head shaking, inappetence.
• Dental Disease: Plaque, tartar, caries, enamel discoloration.
3. Drugs:
• Dentin Sealant, Bonding Agents: For enamel defects.
• Resin Restoration: Enamel repair.
4. Infectious Agents:
• Canine Distemper, Bovine Viral Diarrhea: Associated with enamel hypoplasia.
5. Diagnostic Methods:
• Clinical Examination, Radiographs: To assess teeth and bone structure.
6. Treatment Protocols:
• Extraction, Dental Cleaning: For retained teeth, dental disease.
• Orthodontic Devices: To correct malocclusions.
7. Prevention and Control:
• Regular Dental Check-ups: Early detection and management.
• Proper Nutrition: To support healthy tooth development.
8. Other Relevant Information:
• Breed Predisposition: Some breeds are more prone to dental anomalies.
• Genetic Counseling: Advisable for breeding animals with known dental defects.
On a farm visit, a calf is noted to have its head lowered and extended forward. Which one of the following conditions is suggested by this appearance?
Cryptosporidiosis
Tetanus
Otitis media/interna
Pneumonia
Polioendephalomalacia
Answer: Pneumonia.
A calf with its head held low and extended is a typical posture of a calf with pneumonia.
Pneumonia can be viral, bacterial, or multifactorial (as in shipping fever).
Otitis media/interna would cause the head to tilt toward the side of the lesion
Refs: The Merck Veterinary Manual online edition. Image courtesy, Nottingham Vet School.
Link: Enzootic Pneumonia of Calves and Shipping Fever Pneumonia
https://www.merckvetmanual.com/respiratory-system/respiratory-diseases-of-cattle/enzootic-pneumonia-of-calves-and-shipping-fever-pneumonia
Link: Otitis Media and Interna in Animals
https://www.merckvetmanual.com/ear-disorders/otitis-media-and-interna/otitis-media-and-interna-in-animals?autoredirectid=14210&autoredirectid=219
Which one of the following choices correctly explains how dobutamine increases blood pressure?
Beta-1 receptor stimulation, increasing myocardial contractility
Decreases release of norepinephrine, producing vasoconstriction
Inhibits dopamine secretion in the vasomotor center of the brain
Alpha - 1 blockade peripherally to increase venous return to the heart
Cardiac muscarinic receptor activation increases heart rate
Answer: Beta-1 receptor stimulation, increasing myocardial contractility.
A beta-1 agonist, dobutamine increases the strength of myocardial contraction to increase blood pressure.
Dobutamine is a very potent inotrope with a short half-life. It must be diluted and administered as an infusion to improve cardiac function in anesthetized and critical care patients.
Decreased release of norepinephrine is the mechanism of action of alpha-2 receptor agonists such as xylazine and medetomidine.
Muscarinic M2 receptor blockade in the heart inhibits cardiac parasympathetic tone, allowing sympathetic tone to have a greater effect and heart rate increases. See this with anti-cholinergics such as atropine and glycopyrrolate.
Antagonism of alpha-1 receptors produces vasodilation and sometimes hypotension. This effect is seen with acepromazine.
Refs: Grimm, Tranquilli, and Lamont’s Essentials of Anes and Analgesia in SA, 2nd ed. pp. 232-3.484 Plumb’s Veterinarv Drup Handbook. 7thed.. nn. 465-7
This adult male rat is presented for evaluation of a mass that the owner noticed recently. What is the most likely cause of this mass?
Mammary fibroadenoma
Enlarged peripheral lymph node
Chronic self-trauma
Squamous cell carcinoma
Chromodacryorrhea
Answer: Mammary fibroadenoma.
Benign mammary tumors (fibroadenomas) are the most common subcutaneous tumors in rats.
They can occur in males or females anywhere from the inguinal area to the neck due to rats’ extensive mammary tissues.
Prognosis is good with surgical removal, but tumors can recur in previously unaffected mammary tissue.
Chronic mechanical self-trauma on the cage is associated with alopecia and dermatitis.
Chromodacryorrhea (or “red tears”) occurs in stressed or diseased rats when the Harderian glands behind the eyes secrete increased porphyrins.
Squamous cell carcinoma is uncommon in rats.
Ref: Quesenberry, Carpenter. Ferrets, Rabbits and Rodents Clinical Medicine and Surgery, 3rd ed. p. 362. Image courtesy of Youngamerican.
Which one of the following live vaccines for cattle against Brucella abortus is preferred because of its increased safety profile and ability to differentiate vaccinated from infected animals?
Strain 19
Strain 104-M
Strain RB51
Strain H38
Rev-1
Answer: Strain RB51
Strain RB51 is a live vaccine against B. aborts that is less virulent than other available vaccines in humans and less abortigenic in cattle.
It also does not generate antibodies that cause a positive response in typical serological diagnostic tests.
Strain 19 is an effective vaccine but is more virulent and results in antibodies that may confuse diagnostic testing.
Rev-1 is a live vaccine used to vaccinate small ruminants against B. melitensis.
Strain H38 is a killed vaccine against B. melitensis.
Strain 104-M is a spontaneously attenuated vaccine against B. abortus that has been used for many years in humans in China.
Link: Brucellosis in Cattle
https://www.merckvetmanual.com/reproductive-system/brucellosis-in-large-animals/brucellosis-in-cattle
Brucellosis in Cattle
1. General Concepts and Diseases:
• Brucellosis: Caused by Brucella abortus, leading to abortion, stillbirths, retained placentas, and reduced milk production.
2. Symptoms and Clinical Presentations:
• Abortion storms, stillborn or weak calves, retained placenta, decreased milk production, orchitis, epididymitis in bulls, arthritis in chronic cases.
3. Possible Drugs Used:
• No practical treatment; focus is on detection and prevention.
4. Infectious Agents:
• Bacteria: Brucella abortus.
5. Diagnostic Methods:
• Serologic Tests: Serum agglutination, ELISA, complement fixation.
• Culture: From placenta, udder secretions, fetal tissues.
6. Treatment Protocols:
• No treatment; culling of infected animals, vaccination of young heifers (Strain 19 or RB51).
7. Prevention and Control:
• Regular testing, culling of reactors, vaccination, isolation of new animals.
8. Other Relevant Information:
• Control relies heavily on biosecurity and management practices to prevent spread.
Which of these forceps is used to clamp intermediate-sized blood vessels?
Halsted forceps
Crile forceps
Allis forceps
Brown - Adson forceps
Answer: Crile forceps.
Kelly and Crile forceps are medium-sized hemostats, used to clamp off intermediate-sized blood vessels.
Halsted “mosquito” forceps are tiny hemostats used to clamp small bleeding vessels.
Adson and Brown-Adson forceps are so-called “thumb forceps” (held in a pencil grip, like chop sticks) used to hold tissue.
Allis tissue forceps have teeth on the gripping end, like a horse’s teeth, and can cause trauma to delicate tissue.
Refs: Bassert and Thomas, McCurnin’s Clinical Textbook for Veterinary Technicians, 8th ed. pp. 1139-40 and Tighe and Brown, Mosby’s Comprehensive Review for Vet Techs, 2nd ed. pp. 349-53
Which of these forceps is used to clamp intermediate-sized blood vessels?
Halsted forceps
Crile forceps
Allis forceps
Brown - Adson forceps
Answer: Crile forceps.
Kelly and Crile forceps are medium-sized hemostats, used to clamp off intermediate-sized blood vessels.
Halsted “mosquito” forceps are tiny hemostats used to clamp small bleeding vessels.
Adson and Brown-Adson forceps are so-called “thumb forceps” (held in a pencil grip, like chop sticks) used to hold tissue.
Allis tissue forceps have teeth on the gripping end, like a horse’s teeth, and can cause trauma to delicate tissue.
Refs: Bassert and Thomas, McCurnin’s Clinical Textbook for Veterinary Technicians, 8th ed. pp. 1139-40 and Tighe and Brown, Mosby’s Comprehensive Review for Vet Techs, 2nd ed. pp. 349-53
A 4-month-old terrier cross presents for inability to eat. The puppy is bright, alert, and responsive on exam. Heart rate is 148, respiratory rate is panting, and temperature is 101.8 F (38.8 C). The puppy is extremely painful when his lower jaw is palpated, and cries and pulls away when you attempt to open his mouth. Sedated oral exam is unremarkable. Radiographs are available for review (see image). What do you tell the owner about prognosis?
Chemotherapy can prolong quality of life for few of months, however prognosis is grave
This will regress within a year, and symptomatic support is needed for discomfort
This can be cured with antibiotics bases on culture and sensitivity. NSAIDs can be used for discomfort
Surgical removal of detigerous cysts will likely be curative, however long term dental disease is common
Answer: This will regress within a year, and symptomatic support is needed for discomfort.
Craniomandibular osteopathy (CMO) is seen in young dogs and is exemplified in this radiograph. Terrier breeds predominate, but CMO can be seen in any breed. The disease is usually self-limiting and typically regresses by 1 year old, although not always. It is thought to be a type of hypertrophic osteodystrophy (HOD) and occurs mostly in the mandible but can also affect the tympanic bulla, temporal bones, and temporomandibular joints. Treatment is supportive with nonsteroidal anti-inflammatories to control pain, similar to HOD. Prognosis is highly dependent upon whether the patient is able to open/close the mouth, prehend and chew food, and generally sustain themselves through the course of the disease. Radiographic signs will also regress with time.
Minimum alveolar concentration (MAC) is the minimum concentration of anesthetic in the alveolar gas that prevents a physical response in 50% of animals exposed to a surgical stimulus. It is a measure of anesthetic potency. Which of the following inhalant anaesthetic has the lowest MAC?
Propofol
Guaifenisin
Desflurane
Sevoflurane
Isoflurane
Answer:Isoflurane.
Isoflurane has the lowest minimum alveolar concentration (MAC) of 1.2 in dogs, 1.63 in cats, and 1.31 in horses.
Sevoflurane has an intermediate MAC of 2.1 in dogs, 2.58 in cats, and 2.31 in horses.
Desflurane has the highest MAC at 7.2 in dogs, 9.8 in cats, and 7.6 in horses.
Propofol and guaifenesin are not inhalant anesthetics.
Inhalants with high potency have a lower MAC (need less drug to achieve anesthetic plane). These are also more soluble in blood and tissues; e.g., isoflurane is more soluble, desflurane is less soluble.
The requirement (%) for less soluble drugs is greater, but induction is much faster.
Anesthesia occurs only when the concentration of inhalant in the blood and alveoli are equal. Less soluble drugs achieve this equilibrium faster.
Since there is less drug in the tissues, recovery is also faster compared to more soluble drugs. When the vaporizer is turned off, alveolar levels drop rapidly, followed by blood and tissue levels.
Refs: Bassert, Beal and Samples, McCurnin’s Clinical Textbook for Veterinary Technicians, 9th ed., p. 1018 and Fossum’s Small Animal Surgery, 5th ed., pp. 125-39, and Auer and Stick Equine Surgery, 5th ed., p. 301.
Which of these gross pathology findings would be highly suggestive of African horse sickness?
Necrotic Peyer’s patches, abdominal aortic thrombus
Anemic infarct in the liver, salivary hyperplasia
Excessive, grey-yellow, turbid synovial fluid without joint erosion
Cerebral cavitation, swelling of the spinal column
Supraorbital fossa edema, hydopericardium
Answer: Supraorbital fossa edema, hypropericardium.
Swelling of the supraorbital fossa and hydropericardium would be highly suggestive of the cardiac form of African horse sickness (AHS). Click here to see supraorbital fossa swelling.
Additional necropsy findings for the cardiac form might include endocardial and epicardial petechiae and ecchymoses; flaccid or edematous lungs; and yellow, gelatinou: infiltrations of the subcutaneous and intramuscular tissues.
AHS is a viral foreign animal disease characterized by acute, subacute, or subclinical pulmonary and/or cardiac clinical signs. The principle vector is Culicoides spp.
Refs: Merck Veterinary Manual online edition.
Link: African Horse Sickness
https://www.merckvetmanual.com/generalized-conditions/african-horse-sickness/african-horse-sickness?autoredirectid=16664
A 4-year-old female dachshund is presented with a caudal mammary mass. Thoracic radiographs are taken to rule out the possibility of metastasis. Which one of the following choices is the most likely diagnosis?
Left ventricular enlargement
Normal radiographs
Pulmonary hypertension / vascular pattern
Left atrial enlargement
Metastatic lung disease
These are normal thoracic radiographs. In barrel-chested dogs, the heart appears to take up more of the thoracic volume than in deep-chested dogs.
Click here to see more normal canine thoracic radiographs.
https://vetmed.illinois.edu/imaging_anatomy/canine/thorax/ex02/thorax02.html
Refs: Thrall, Textbook of Veterinary Diagnostic Radiology 6th ed. pp. 474-88 Radiographic interpretation and images courtesy, Dr. A. Zwingenberger and Veterinary Radiology.
Link: Radiography of Animals
https://www.merckvetmanual.com/clinical-pathology-and-procedures/diagnostic-imaging/radiography-of-animals?redirectid=4195?ruleredirectid=30&autoredirectid=12769
Link: Normal Thorax
http://mirc.veterinaryradiology.net/storage/ss1/docs/20081210114727215/MIRCdocument.xml
What is a dermoid sinus?
A cystic structure most frequently located just ventral to the ear of dogs
A tubular skin lesion on the dorsal midline of dogs
A space occupying mass located in the dermis overlying the philtrum of dogs
A fistulous tract over the tail of dogs affected with flea allergy dermatitis
An adenoma in the frontal sinus of dogs
Answer: A tubular skin lesion on the dorsal midline of dogs.
Dermoid sinuses are congenital neural tube defects most frequently observed in Rhodesian Ridgeback dogs, in which they are believed to be hereditary.
The sinus may be a blind-ended sac terminating just beneath the skin, or, in more serious cases, may communicate with the dura mater. Meningitis (and associated neurologic deficits) may occur in cases of infected sinuses communicating with the dura mater.
Additional information about the extent of the sinus may be gathered via fistulography and myelography if necessary. Treatment involves complete surgical excision of the sinus tract.
Click here to see a good summary on dermoid sinus or pilonidal sinus with images, courtesy of the American College of Veterinary Surgeons (ACVS).
https://www.acvs.org/small-animal/dermoid-sinus/
What pathologic process is evident in the canine radiograph below?
Answer: Neoplasia.
This is a classic image of osteosarcoma, a common, aggressive bone tumor typically found in the appendicular skeleton. Common sites include the distal radius and proximal humerus (away from the elbow), and distal femur and proximal tibia (towards the knee), but these tumors can occur in any bones, including the mandible, maxilla, and vertebrae.
Dx: Bone biopsy is typically required to differentiate between infection and neoplasia. Fine needle aspirate cytology may provide an answer in some cases
Usually, does not cross the joint (unlike osteomyelitis, which usually does cross joint if bone involved is close to the joint). Look for soft tissue swelling, periosteal proliferation, sunburst periosteal reaction (33%), +/- pathologic fractures.
Link: Bone Tumors in Dogs and Cats
https://www.merckvetmanual.com/musculoskeletal-system/osteopathies-in-small-animals/bone-tumors-in-dogs-and-cats`\
A five-year-old male neutered domestic shorthair cat is presented with a two-week history of lethargy, anorexia, and weakness. Exam reveals pale mucous membranes, thin body condition, and moderate splenomegaly. What is the treatment of choice?
Answer: Doxycycline
This is the anemia of Mycoplasma haemofelis (a.k.a. hemotropic mycoplasmosis, feline infectious anemia), Tx with doxycycline (or a fluroquinolone) +/- prednisolone if severe hemolysis. Look for a regenerative anemia, hyperbilirubinemia and cocci/rings on edges of red blood cells on blood smear.
Tx: Doxycycline for a minimum of 14 d, but will not completely eliminate infection and treated cats may remain PCR positive without clinical signs. Doxycycline can cause esophagitis/ esophageal stricture in cats, always following pilling with food/ water or use a liquid formulation.
Link: Hemotropic Mycoplasma Infections in Animals
https://www.merckvetmanual.com/circulatory-system/blood-parasites/hemotropic-mycoplasma-infections-in-animals?autoredirectid=17928
A group of 12-week-old feeder pigs are presented with mild lethargy and keratinized skin lesions. They are not pruritic. One severely affected animal is depressed and anorexic. Exam of a severely affected pig reveals symmetrically distributed areas of excessive keratinization with horny scale that is easy to remove and fissures all over the body. A few pigs have brown spots and papules around their tails and on the ventrolateral abdomen and inner thighs. What treatment is most appropriate for the presumptive diagnosis?
Copper sulphate bath or sprays
Supplement dietary zinc
Spray with malathion (0.05%)
Ivermectin SQ now, repeat in 2 weeks
Answer: Supplement dietary Zinc
Supplement these pigs with zinc to resolve clinical signs. Zinc deficiency causes parakeratosis. Starter diets should contain 125 ppm zinc (and 0.9% calcium). Grower diets should contain 75 ppm zinc (and 0.60-0.65% calcium). Finisher diets should contain 50 ppm zinc (and 0.45 to 0.50% calcium).
Parakeratosis may resemble exudative epidermitis (“greasy pig disease”), caused by Staphylococcus hyicus. Exudative epidermitis is more typically seen in younger piglets (one to ten weeks old) and is treated with antimicrobials.
Sarcoptic mange (Sarcoptes scabiei var suis) is typically pruritic and treated with antiparasitics like ivermectin or pigs may be sprayed with lindane (0.05-0.1%) or malathion (0.05%).
https://www.merckvetmanual.com/integumentary-system/parakeratosis/parakeratosis-in-pigs?autoredirectid=16692
https://www.merckvetmanual.com/integumentary-system/exudative-epidermitis/exudative-epidermitis-in-pigs?mredirectid=836
https://www.merckvetmanual.com/integumentary-system/mange/mange-in-pigs
Parakeratosis in Pigs
Definitions and Causes:
• Parakeratosis: Nutritional deficiency disease in pigs, characterized by superficial epidermal lesions.
• Causative Agents: Zinc deficiency or poor absorption due to excess calcium, phytates, or other chelating agents in the diet. Rapid growth and malabsorption due to gastrointestinal disease are predisposing factors.
Physiopathology:
• Zinc is crucial for proper keratinization. Deficiency leads to abnormal keratinization and epidermal lesions.
Symptoms and Clinical Changes:
• Lesions: Symmetrical, excessive keratinization, horny scales, fissures. Lesions start as brown spots or papules on the ventral abdomen, inner thighs, and legs.
• Additional Signs: Mild lethargy, anorexia, delayed growth. Rarely pruritus.
Diagnosis:
• Clinical Signs: Visible skin lesions.
• Laboratory Tests: Low serum zinc, decreased alkaline phosphatase activity.
• Differential Diagnoses: Sarcoptic mange, B vitamin deficiency, iodine deficiency.
Treatment and Medications:
• Dietary Adjustment: Increase zinc intake, reduce calcium levels.
• Nursery pig diets: 0.8%-0.85% calcium, 100 mg/kg zinc.
• Grower diets: 0.6%-0.65% calcium, 60 ppm zinc.
• Finisher diets: 0.45%-0.5% calcium, 50 ppm zinc.
• Sow/boar diets: 0.9% calcium, 150 ppm zinc.
Prognosis:
• Rapid recovery with dietary correction.
Which one of the following choices is the most likely source of the yellowish-white 1-2 mm eggs found on the hairs of this horse’s forelimb?
Blowfly
Screw-worm
Harvest mite
Gasterophilus spp.
Forage lice
Answer: Gasterophilus spp
These are the eggs from botflies (Gasterophilus spp.). The fly lays eggs on the hairs of the horses forelimbs or shoulders and are stimulated to hatch by the horse licking. The larvae (bots) become embedded in the horse’s mouth for a month then pass to the stomach. The bots can be asymptomatic or cause a mild gastritis.
Harvest mites (trombiculidiasis), or chiggers, cause pruritus, papules, and wheals. Pruritus can be treated with glucocorticoids, and repellents may also be useful.
https://www.merckvetmanual.com/digestive-system/gastrointestinal-parasites-of-horses/gasterophilus-spp-infection-in-horses?redirectid=27858
https://www.merckvetmanual.com/integumentary-system/mange/mange-in-horses
An eight-year-old Tennessee Walker mare is presented for evaluation. She was accidentally turned out with a stallion a couple of times about three or four weeks ago. Transrectal ultrasound of the uterus reveals the following. What can the owner be told?
Endometritis with endometrial cysts
There was uterine trauma
Twin fetuses present
Normal estrus uterus
Mare is pregnant
Answer: Mare is pregnant
The mare is pregnant - this ultrasound image shows a 25-day-old conceptus. The yolk sac (dorsal) and allantoic cavity (ventral) are nearly the same size, divided by the embryo.
The heart beat is visible beginning at day 25 (and was visible here on video).
A 2-week pregnancy is imaged as a small, round, anechoic structure with bright hyperechoic dashes on the dorsal and ventral aspect of the yolk sac (called “specular reflectors”),
located within the lumen of the uterus.
This image is not consistent with uterine trauma, endometritis, or a twin pregnancy.
https://www.merckvetmanual.com/management-and-nutrition/management-of-reproduction-horses/pregnancy-determination-in-horses
What does the following image of a horse illustrate?
Normal teats
Mastitis
Contagious agalactia
Normal sebaceous plugs
Waxing
Answer: Waxing
These are the waxing teats of a mare about to foal in 6 to 48 hours. “Waxing” happens in about 95% of mares before foaling. This can fall off or get knocked off so it’s possible to miss seeing it.
In the final two to three days of pregnancy, the teats of most mares distend with colostrum. Colostrum drips and dries on the nipples to make a waxy coating at each teat orifice.
In approximately 85% of bitches the body temperature drops to 99ºF (37.2°C) about 24 hrs before the onset of stage Il labor. Take a bitch’s temperature at a consistent time each day for this to be a reliable indicator.
Will see relaxation of the pelvic ligaments associated with impending parturition in mares and cows - this gives the newborn more space to pass through the pelvic canal.
Most mammals (including sows) become restless and show signs of nesting. Often the respiratory rate increases.
Queens will often experience a decrease in appetite prior to parturition.
https://www.merckvetmanual.com/management-and-nutrition/management-of-reproduction-horses/parturition-in-horses
https://www.merckvetmanual.com/management-and-nutrition/management-of-reproduction-dogs-and-cats/whelping-and-queening-in-dogs-and-cats
https://www.merckvetmanual.com/management-and-nutrition/management-of-reproduction-dogs-and-cats/labor-and-delivery-in-dogs-and-cats
A birnavirus causes which one of these avian diseases?
Answer: Infectious bursal disease
Infectious bursal disease (IBD) is caused by a birnavirus.
Click here to see an enlarged, balloon-like hemorrhagic bursa of Fabricius, characteristic of IBD.
IBD is shed in feces and transferred barn to barn via fomites. Very stable. Difficult to eradicate from premises.
Signs include clinical picture given above in older birds, or MORE IMPORTANT subclinical form in young birds, which causes immunosuppression via destruction of immature lymphocytes in bursa, thymus, spleen.
Immunosuppressed birds do not respond well to vaccination and are predisposed to infections with normally nonpathogenic viruses and bacteria.
Common diseases usually exacerbated by IBDV infections. See large economic losses.
Ref: The Merck Veterinary Manual online edition.
Link: Infectious Bursal Disease in Poultry
https://www.merckvetmanual.com/poultry/infectious-bursal-disease/infectious-bursal-disease-in-poultry
Infectious Bursal Disease (IBD) in Poultry
Definition:
• IBD: A viral disease affecting young chickens, also known as Gumboro disease.
Causative Agent:
• Infectious Bursal Disease Virus (IBDV): Double-stranded RNA virus, Avibirnavirus genus, family Birnaviridae.
Symptoms:
• Clinical Signs: Listlessness, watery diarrhea, ruffled feathers, dehydration, severe prostration, incoordination, soiled vent feathers, vent picking, inflammation of the cloaca.
• Lesions: Enlarged, edematous cloacal bursa with possible hemorrhages.
Diagnosis:
• Observation: Gross and microscopic lesions in cloacal bursa.
• Molecular Testing: RT-PCR for viral RNA, virus isolation.
Treatment and Control:
• No Treatment: Focus on control through rigorous disinfection and vaccination.
• Vaccination: Live attenuated and vectored vaccines for active immunity, vaccination of breeder flocks to induce maternal immunity in chicks.
Important Points:
• IBDV causes immunosuppression by targeting immature B lymphocytes.
• High morbidity, variable mortality depending on strain and breed.
What is initially recommended for horses who suffer from uncomplicated intermittent delayed release of the patella (blue arrow) from its position over the medial trochlear ridge of the femur?
Answer: Controlled exercise program.
A controlled conditioning exercise program is often the first recommendation in horses with intermittent delayed patellar release (a.k.a. intermittent upward fixation of the patella).
This helps strengthen the quadriceps (and biceps femoris) muscles of the thigh and therefore removal of the patella from its “locked” position over the medial trochlear ridge.
This condition occurs when the medial patellar ligament stays hooked over the medial trochlear ridge of the femur, thereby locking the reciprocal apparatus with the limb in extension. Horses with intermittent delayed patellar release are slow to release the patella during limb protraction, which is visible when transitioning from canter to trot.
Horses with severe disease stand with the hind limb in extension and fetlock flexed. Those horses may not be able to move forward, or only do so with a sudden jerking flexion of that limb.
Tx for horses who do not respond to conservative therapy, are lame, or who have severe disease: medial patellar ligament desmotomy or medial patellar ligament splitting procedures.
It is important to provide good farriery care to ensure the foot is well balanced. Shoes with a beveled edge (and possibly a lateral heel wedge) may be helpful.
Arthroscopy would not be an initial treatment for this condition.
The tibial plateau leveling osteotomy is performed in dogs with cranial cruciate injuries.
Link: Intermittent Upward Fixation of the Patella and Delayed Patella Release in Horses
https://www.merckvetmanual.com/musculoskeletal-system/lameness-in-horses/intermittent-upward-fixation-of-the-patella-and-delayed-patella-release-in-horses
Link: Cranial Cruciate Ligament Disease.
https://www.acvs.org/small-animal/cranial-cruciate-ligament-disease/
Intermittent Upward Fixation of the Patella and Delayed Patella Release in Horses - Comprehensive Veterinary Information
Definitions and Terminology:
• Intermittent Upward Fixation of the Patella: Medial patellar ligament locks over the medial trochlear ridge of the femur, causing the hind limb to remain extended.
• Delayed Patella Release: Jerky movement of the patella during limb protraction, often seen in young, poorly muscled horses or older horses with stifle trauma.
Physiopathology:
• Mechanism: Medial patellar ligament fails to release, causing the limb to be locked in extension.
Clinical Findings:
• Symptoms: Sudden locking of the hind limb, jerky patellar movement, low-grade lameness, reluctance to work on soft surfaces or inclines.
Diagnosis:
• Clinical Signs: Observation of limb fixation, induced by pushing the horse backward or manually manipulating the patella.
• Radiography: Used if there is effusion or lameness to identify secondary pathology.
Treatment:
• Non-surgical: Conditioning program (daily lungeing or riding), good nutrition, balanced foot trimming, shoeing.
• Surgical: Medial patellar ligament desmotomy for severe or non-responsive cases.
Prognosis:
• Generally Good: With conservative treatment or surgery, although recurrence is rare after desmotomy.
Which drug will make a cat’s eyes look like this?
Tripicamide
Pilocarpine
Atropine
Diazepam
Dentrolene
Pilocarpine is a topical miotic agent (pupil constrictor) used mainly to diagnose cranial nerve lil lesions. It is also used in the treatment of glaucoma to open the iridocorneal angle and decrease intraocular pressure. It is a muscarinic receptor agonist.
Expect mydriasis (dilated pupils) with atropine and glycopyrrolate. These anticholinergic drugs are primarily used as preanesthetics to prevent bradycardia and decrease airway secretions. Topical atropine is used in the treatment of anterior uveitis and painful corneal diseases.
Tropicamide is a topical mydriatic agent.
Dantrolene is a muscle relaxant used for post-anesthesia myositis in horses and in dogs and cats with functional urethral obstruction.
Refs: Cote, Clinical Veterinary Advisor: Dogs and Cats, 4th ed., pp. 846-47, and Plumb’s Veterinary Drug Handbook, online edition; Pilocarpine. Image courtesy of Fedor Leuhkin.
Link: Treatment of Glaucoma in Animals
https://www.merckvetmanual.com/pharmacology/systemic-pharmacotherapeutics-of-the-eye/treatment-of-glaucoma-in-animals
Link: Systemic Treatment of Inflammatory Airway Disease in Animals
https://www.merckvetmanual.com/pharmacology/systemic-pharmacotherapeutics-of-the-respiratory-system/systemic-treatment-of-inflammatory-airway-disease-in-animals?autoredirectid=17111#v12763244
