FAMS Exam 2 Flashcards
What is the term for the disease caused by Trichophyton verrucosum?
(Ringworm/dermatophycosis)
What is the most common causative agent of ringworm?
(Trichophyton verrucosum)
Why is it important to know that Trichophyton verrucosum is spore forming?
(This is the causative agent for ringworm, spore forming indicates that it will live in the environment for a long time)
(T/F) You cannot write a health certificate for an animal with ringworm.
(T, both transmissible and zoonotic)
Why do ringworm lesions typically pop up on the head and neck in cattle?
(Bc they communicate with each other and the world with their heads → rub on stuff, lick stuff, etc.)
Are ringworm lesions typically pruritic?
(No)
What should you assess in a cow with extensive ringworm lesions?
(Immune function, could indicate there is immune compromise such as BVDV PI, chronic lymphoma, etc.)
(T/F) Ringworm is not associated with any production losses in cattle.
(T)
Using topical clotrimazole is an option for treatment of ringworm in cattle, what is the meat withdrawal period?
(24 hours/1 day)
What will indicate if a ringworm lesion is no longer infected and is healing?
(When hair is growing back in the middle of the lesion)
What is the pathophysiology behind primary photosensitization?
(Animal obtains a photodynamic agent (from ingestion, injection, or absorption) which then reacts to UV light in the skin, free radicals are released which damage cell and lysosomal membranes of skin cells causing ulceration, necrosis, and edema)
Why does primary photosensitization only affect the non-pigmented skin of cattle?
(Because pigmented skin contains melanin which is protective against the UV light needed to react with the photodynamic agents)
Photosensitization is more likely to affect dairy/beef (choose) cattle and why.
(Beef, they are out on pasture and exposed to the sun)
What two forages primarily cause primary photosensitization?
(Legumes and Brassica)
What antibiotic does Dr. Guynn suggest for use in cases of primary photosensitization that she usually doesn’t use in beef cattle?
(Excede → works on skin lesions and lasts a long time)
Why is the prognosis poor for secondary photosensitization when it is good for primary photosensitization?
(Because secondary is associated with liver damage, not a lot to do to fix the liver in cattle)
Why is bovine ulcerative mammilitis associated with cold weather?
(Because the virus that causes it (bovine herpes virus II and IV) replicates at lower temperatures)
The use of what type of PPE is important for preventing the spread of pseudocowpox from cattle to humans?
(Gloves)
What are cow related risk factors for teat-end hyperkeratosis?
(Teat conformation (long and pointy is no good), age (older), being later in lactation, longer milking time (higher production or slow milker), and questionably genetics)
What are the two etiologies of the impaired blood and lymph circulation that leads to udder edema?
(Pressure from the fetus and/or the decrease in protein oncotic pressure as IgG is being diverted to the udder)
Why should you perform a skin scrape on udder cleft dermatitis lesions?
(They have an associated with sarcoptic mange)
What are the three causes of polioencephalomalacia?
(1- Ingestion of plants containing thiaminases; 2 - rumen acidosis from eating too much high starch grain with secondary lack of production of thiamine (rare cause); 3 - eating a lot of corn gluten or distillers grain which will contain more that 0.4% sulfur)
What are the main clinical signs of polioencephalomalacia in cattle?
(Blindness, staggering, down, and seizures)
A deficiency in what vitamin reduces the energy available for sodium/water transport mechanisms in the cells of the brain which leads to PEM?
(Thiamine → cofactor for enzymes associated with energy production in the brain)
How does the response to thiamine supplementation for the treatment of PEM differ between if the PEM is non-sulfur or sulfur induced?
(Non-sulfur → up and running around in 15 minutes after giving thiamine versus sulfur induced → you look for 50% improvement in the first 24 hours after starting tx, takes days for 100% improvement and there is a good chance for relapse if thiamine tx is stopped too early)
What is the number one source of lead poisoning in cattle?
(Batteries, have you ever put your tongue on a 9v battery just to feel alive?)
Lead intoxication is acute/chronic (choose).
(Tricky me, cattle may develop signs of lead intoxication from ingestion of a single dose of lead (400-800 mg/kg) or low levels of lead (6 mg/kg) for longer periods of time)
What is the best treatment for lead intoxication?
(Calcium EDTA at various doses → binds lead)
Why is it controversial to treat lead intoxication?
(Hard to establish an appropriate withdrawal time and there is a possibility for future release of lead from the rumen, Dr. Currin usually goes with a 12 month minimum slaughter withdrawal)
Thrombotic meningoencephalitis (TME) is a fulminant neurological disease of cattle caused by what bacteria?
(Histophilus somni)
What is the causative agent of sleeping sickness in cattle?
(Histophilus somni, sleeping sickness is a trade name for thrombotic meningoencephalitis)
What is the antibiotic of choice for treatment of TME?
(Florfenicol → good penetration into brain tissue)
What is the most common way that listeria is obtained in cattle?
(Ingesting poorly ensiled feed → pH > 4.5 or moldy edges)
Listeria unilaterally affects which cranial nerve in cattle?
(The trigeminal nerve)
What are the four things that are needed to make appropriately ensiled feed?
(Moisture, anaerobic environment, bacteria, and a substrate for the bacteria to eat (usually starches))
Why should you not allow water deprived cattle to drink as much water as they want?
(Because salt has been packed away into the cells of the brain making them hyperosmolar and when they ingest a bunch of water, that water rushes into the cells and causing them to swell → brain edema, increased ICP, encephalopathy)
A sodium value of what or greater on a chemistry panel indicates salt intoxication?
(> 160 mEq/L)
At what rate should water be reintroduced to water deprived cattle?
(1-3 gallons every 6 hours for 24 hours)
What are the clinical signs associated with radial nerve paralysis?
(Dropped elbow and inability to extend the affected leg)
Radial nerve paralysis occurs secondarily to what issue?
(Prolonged lateral recumbency → why you usually limit time in tilted chutes to 30 minutes especially for larger cattle)
What is a cattle specific rabies clinical sign?
(Tenesmus)
How long does it take Trichostrongylus spp. to develop once eggs are passed in the manure?
(5-7 days to get to L3, if its cooler it will take longer)
Once L3 Trichostrongyles become adults in their hosts, how long does it take them to start laying eggs?
(3 weeks)
What are the two main important Trichostrongylus spp. that affect cattle?
(Ostertagia and Cooperia, there are other species present that contribute to parasitic gastroenteritis but rarely are the primary pathogens)
(T/F) Most strongylid eggs in the manure of young cattle are Cooperia spp.
(T)
The macrocyclic lactone dose for the treatment of Cooperia spp. in cattle is higher/lower (choose) than that needed to treat Ostertagia.
(Higher)
Why are Trichostrongyle infections greatest in younger cattle?
(Bc immunity develops over several years)
What results from subclinical Trichstrongyle infections?
(Decreased weight gain and growth from anorexia and gastric disturbance)
Trichostrongylus spp. infections typically are subclinical but when they become clinical, what signs do you typically see?
(Diarrhea, weight loss, unthriftiness, and hypoproteinemia)
What dewormer drug class is available in pour on formulas?
(Macrocyclic lactones → ivermectin, doramectin, eprinomectin, and moxidectin all have pour on formulas (as well as injectable))
What dewormer drug classes are available in oral formulas?
(Benzimidazoles (fenbendazole, albendazole, oxfendazole) and nicotinics (levamisole, morantel))
Parasite impact is higher on dairy/beef (choose) productions.
(Beef)
Anthelmintic resistance is an issue for all three of the major drug classes but is particularly bad for which drug class?
(Macrocyclic lactones → it is heavily used d/t pour on convenience and low cost)
How is anthelmintic resistance tested for in cattle?
(Fecal egg count reduction test → looking for drug efficacy over 90%)
How long should you wait before taking your comparison fecal egg count reduction test sample when testing a macrocyclic lactone? What about a benzimidazole?
(ML → 14-17 days (moxidectin 17-21), BZD → 10-14 days)
If your reduction in fecal egg count is 90% after using an anthelmintic, would you say that drug has:
A - Full efficacy
B - Possible resistance
C - Likely resistance
D - Highly likely resistance
(B, 95% and above is full efficacy, 90-95% is possible resistance, 80-90% is likely resistance, and <80% is highly likely resistance)
What is the main way producers are getting around anthelmintic resistance in their cattle?
(Combination treatment with two different drug classes)
(T/F) Oral administration is the most effective treatment route for intestinal parasites.
(T)
What practices can be put in place to minimize resistance to extended release eprinomectin?
(Do not use year after year as a sole method, consider combination treatment, leave a refugia, and use other methods of parasite control such as pasture management)
What is the main strategy used to maintain refugia in cattle?
(Selective non-treatment → leave 10-20% of the animals untreated; cannot easily ID animals that need tx bc fecal egg counts are not predictive and neither are using their weights)
Haemaphysalis longicornis is the vector for which disease?
(Theileria orientalis)
When is Haemaphysalis longicornis active during the year?
(March-November)
How does Haemaphysalis longicornis reproduce?
(Parthenogenetically)
What are the three locations that an esophageal obstruction is likely to occur in cattle?
(Thoracic inlet, right after the pharynx, and base of the heart)
Why would a cow with an esophageal obstruction have an increased lactate?
(Bc she is unable to swallow her saliva which contains sodium bicarb, could also be d/t dehydration)
Why would a cow with an esophageal obstruction be hypokalemic and hypophosphatemic?
(Hypokalemia → not eating but still losing potassium, hypophosphatemia → not swallowing her saliva which contains phosphorus)
What can you do to aid in your decision to treat potential aspiration pneumonia after an esophageal obstruction case?
(Listen to the lungs, if sounds are harsh go ahead and treat, if not tell producer to keep an eye on them)
Esophageal obstruction is more likely to occur in what time period after you clear the initial obstruction?
(Within 24 hours)
When checking the pH of rumen fluid, you should make sure it is definitely rumen fluid and not what other substance that can throw off your pH results?
(Saliva)
Why should you auscultate the lungs in a bloat case?
(If there is pneumonia and subsequent swelling of the bronchial lnn, they could be pushing on the esophagus and preventing eructation, there could also be aspiration pneumonia after bloating)
You should especially palpate the esophagus of calves if they bloated, why is that?
(Checking for a thymoma)
What are your treatment options for frothy bloat? 4 answers.
(Poloxalene, mineral oil, dish washing soap, or a permanent trocar)
Optimally after administering a surfactant in a case of frothy bloat, you would tube the gas out of her rumen instead of depending on her to eructate on her own, why is that?
(Bc she is less likely to eructate on her own due to the distension)
You are called about a cow/heifer with a prolapse of unknown origin coming out the back end, what are your prolapse location options?
(Rectal, vaginal, uterine → uterine is an emergency)
When you receive a call about a potential prolapse in a cow/heifer, what is a primary question you should ask?
(Is she pregnant or has she calved recently?)
You have established that a cow/heifer has a prolapse coming from her vagina and she has recently calved, what do you need to know next?
(If it is long (uterus) or short (vagina) and smooth (vagina) or bumpy (uterus))
What are risk factors for rectal prolapses? 8 answers :).
(Straining d/t tenesmus or dysuria, neuropathy (tail docking, alcohol epidural, spinal lymphoma), chronic coughing, genetics, neoplasia, diet (estrogenic feedstuff), obesity, and hormone treatments)
(T/F) Rectal prolapses are an emergency.
(F, urgent rather than an emergency, see it the next day if call overnight)
How can you gauge the prognosis of a rectal prolapse?
(By grading it (read grades in powerpoint), grade I and II good prognosis with prompt treatment, grade III and IV associated with risk for severe vascular injury to descending colon, requires surgical resection, poor prognosis)
What can be performed if you are attempting to fix a rectal prolapse but the animal is continuing to strain?
(An epidural, caudal in cattle and lumbosacral in other species)
What does it mean that an alcohol epidural is a salvage procedure?
(You are just trying to get them to slaughter at this point)
What does injecting lidocaine or oxytet around the rectum cause to aid in preventing rectal prolapses?
(Adhesions)
What are the complications associated with amputating a rectal prolapse if replacement is not an option?
(Strictures, peritonitis, and abscesses)
One of the risk factors for vaginal prolapses is advanced stage pregnancy d/t increased abdominal pressure, this is especially true for what species in what time of gestation?
(Multiparous ewes in the last 3 weeks of gestation)
Why should you increase concentrate consumption and reduce hay consumption in late gestation ewes with vaginal prolapses?
(That will decrease abdominal filling and hopefully decrease abdominal pressure)
A caslick’s procedure is best performed in what animals for treatment of Grade I vaginal prolapses?
(Non-pregnant animals that experience Grade I eversion during estrus → embryo donors)
Of your short-term retention techniques for vaginal prolapse, which is better for advanced grade and chronic prolapses?
(Buhner stitch, must untie at parturition)
Uterine prolapses are associated with which stage of labor?
(3rd stage, placental expulsion)
What are the risk factors for uterine prolapse? 5 answers.
(Multiparous animals, exposure to estrogenic substances, extreme weather changes and pasture composition changing mineral availability, uterine inertia/hypocalcemia/recumbency, and dystocia/retained fetal membranes/uterine tears)
Why are uterine prolapses an emergency? Be specific.
(Risk of middle uterine artery rupture)
(T/F) Uterine prolapses are not associated with a genetic risk.
(T)
What should you tell a producer to do if you suspect they are calling about a uterine prolapse?
(Do not transport that animal, restrain her, and place a bag over the uterus)
Why might you not reach for sugar in the case of a uterine prolapse?
(It can be irritating and could potentially affect her future fertility, can try glycerol or chlorhexidine ointment with a pressure bandage instead)
You should begin a uterine prolapse reduction with the non-gravid/gravid (choose) horn.
(Non-gravid)