Food Ani. Med- Cardiovascular and Hemolymphatics 2

drraythe's version from 2016-04-29 15:41


Question Answer
if you see an anemic ruminant, think ___(extra or intra) vascular hemolysis first? (Which is more common)EXTRA
where does extravascular hemolysis happen?spleen, liver, BM
which is hemoglobinuria/hemoglobinemia- extra or intravascular hemolysis?INTRA
common parasitic causes of hemolytic anemia? (6)anaplasmosis, babesiosis, haemobartonellosis (now known as Hemotropic Mycoplasmas aka hemoplasmas), eperythrozoonosis, theileriosis, trypanosomiasis
2 bacterial causes of hemolysis?Lepto (toxins) and bacillary hemoglobinuria (C. novyi type D, C. haemolyticum)
3 toxins which cause heinz bodies--> hemolysis?Onion (oxidizing compounds, oxidize and denature Hb--> heinz bodies--> deform RBCs, lysis), Red Maple (when wilted. reactive oxidants, affect RBC glutathione reducing system), phenothiazines (like Acepromazine)
Misc causes of hemolysis which are not parasites, bacteria, or toxins?water intox, postparturient hemoglobinuria (onset of milk production, possibly due to dec P which inc osmolar fragility), Cu toxicity
mycoplasma hemolytica: intra or extravascular hlysis?extra
red water (bacillary hemoglobinuria): extra or intra? (causative agent? why does it cause hlysis?)intra, clostridium hemolyticum (or c. noyvi type D), via BETA TOXIN (Can vx)
which anaplasma causes hlysis in cattle? how does it do this? is it extra or intravascular hlysis?Anaplasma marginale, vector borne (ticks) or iatrogenically transmitted protozoan which infects RBCs directly and causes hlysis... extravascular
what determines if a anaplasma marginale infection is mild or severe?AGE! calf=mild (gain natural immunity), adult is severe (fever, serious hypoxia, icterus, constipation, yellow urine, abortion)
can you dx a. marginale with a blood smear? only useful in acute cases(same for PCR). cELISA good for outbreaks or chronic/carriers
tx for a. marginale?(in endemic areas, calfhood exposure-->life long subclinical carriers) TX with tetracyclines (chemosterilization very difficult, oral chlortetracycline)
so A. marginale is extravascular hemolysis and it lives in the RBCs. Why isnt it always easy to detect A. marginale, and why can the rate of lysis be really fast?because it is an UNDULATING event, esp the presentation of the antigens. However, Abs might be misinformed and recognize normal RBCs and so rate of hlysis might be really fast
what are the two kinds of babesia which affect rumis? which is more virulent? how do cows get it?It is a tick-borne intraerythrocytic protozoa. there is Babesia Bigemina (large and common) (bigemina, large protozoa and large amount of times seen), and Babesia Bovis (small and virulent) (bovis is a LITTLE bitch)
explain transmission of babesiapreg female rhipicephalus tick ingests infected blood- transmission is transovarial and transstadial. ALL stages can transmit pathogen to host. Can also be spread with blood products or contaminated equipment (rip you a new one, babe)
are adults or calves more suseptible to babesiosis?calves more resistant, post infection become persistent carriers, asymptomatic carrier status can be overcome by stress, etc. Naive infected adults show severe CS
does babesia cause intra or extravascular hemolysis?INTRAVASCULAR (escaping merozoites)
anaplasma vs babesia- intra or extra vascular hemolysis?Anaplasma is extra (anaplasma antigen presenting so in the spleen) Babesia is intra (babesia in the blood)
how severe of a dz is babesiosis?death can occur 2-3wk after a tick bite! (naive adult)
CSs of babesiosis?death, fever, inc HR inc RR, PROFOUND metabolic ACIDOSIS (parasite metabolic products) abortion, anemia, hgemia hguria
what kinda environment do babesia like, what implications does this have?they like anaerobic situations so they can block small capillaries--> sludgeing
Babesa CNS signshyperexcitable, seizure, coma, death. (brain anoxia bc they like anaerobic enviro and block capillaries bc of that)
what kinda blood smear gives you a better chance of seeing the babesia organisms?peripheral (remember they like to be in capillaries which are more peripheral)
what are some preventative methods for avoiding babesia? esp in endemic areas?CALVES have colostral immunity for 9 mo (and also are less affected than adults, can become subclinical carriers remember) endemic areas LET calves get exposed before 6mo old so they can develop immunity. Try to avoid tick stuff.
What can you use to treat babesiosis? what is important to know about treatment? what is prog?You can use diminazene aceturate or imidocarb dipropionate to treat, but it is important to know that if you completely sterilize (get rid of infection) of cow, it can get re-infected. You will need a higher dose to treat a carrier animal. Consider vaccination and controlled exposure for calves/adults. Severe dz has poor prognosis
WHO is most prone to getting copper toxicosis? Who has some resistance?Growing stock-- sheep more than goats. marino have some resistance
how much copper do they need? how much is toxic?there is a very NARROW theraputic window- they need 4-6ppm, but 10-20ppm can cause tox (damn)
which substances change the bioavailability of Cu? (and how)TOO MUCH molybdonum, sulphates, zinc, and iron will DEC the amount of copper in the body
Dont confuse Cu tox and Cu deficiencyDeficiency means not enoguh Cu for enzymes, leads to demyelination (enzootic swayback)/anemia/epiphysitis/diarrhea/change in coat color. TOxicity= accumulate in liver, stress to liver or lysosomes exceed holding capacity-->hemolytic crisis
What is the best ratio of Cu:Mo?6:1
explain pathophys of Cu ToxCHRONIC subclinical accumulation of Cu in hepatocyte--> liver damage. If lysozymes exceed holding capacity OR hepatocytes stressed there is a SUDDEN release of Cu--> hemolytic crisis
What kinda hemolysis does Cu tox cause, and how?Sudden release of lots of Cu, Cu has potent oxidizing properities--> intravascular hemolysis (I mean, its not like toxic oxidizing is gonna wait to be in the spleen or sthing)
what other organ can be 2* affected by Cu tox?Cu tox--> Intra hlysis--> hgburia--> RENAL FAILURE bc damage to renal tubular epithelium by hgb and other filtered substances.
CSs of Cu tox? Prog?***DARK URINE, icterus, anemia, methhgbemia (forms when iron is oxidized-- remember nitrate poisoning from tox?), hepatocellular damage, CSs 2* to renal dz. OFTEN FATAL in sheep
clin path with Cu tox?PCV low, TP high, liver enzymes elevated (high Cu causes hepatocellular damage), azotemia (2* kidney damage from hgb in tubular epithelium), methhemoglobinemia (Cu oxidized Fe to methhgb)
PM findings with Cu tox?icterus, large spleen, friable liver, swollen, dark gun metal kidneys. dark urine in bladder
how can you tx for cu tox?CHELATING AGENTS: (1) Ammonium Molybdate + Sodium thiosulfate (2) Ammonium tetrathiomolybdate (3) Sodium molybdate +/- gypsum calcium sulfate (sooooo basically give them some molybdenum), also give D-penicillamine (also a chelating agent), and support kidneys
what is anthrax, who is most suseptible?G- rod bacillus anthracis, RUmis and humans very suseptible.
what enviro supports anthrax? how dangerous? what usually triggers an outbreak?100% mortality, soils with favorable conditions support spore development. HIGH ph (alkaline), high Ca and Mg. Drought then rain preceeds outbreaks
how does rumi get infected with anthrax?ingest/inhale spores, or wounds/blood sucking parasites, dehorning, castration
explain pathogenesis of anthraxenter body (ingested, wound, etc)--> phagocytized by macrophage and go to LNs--> sudden death with endotoxemia
virulence factors of anthrax?capsule, toxins (protective factor, lethal factor, edema factor)
CSs of toxemia from anthrax?fever, depression, resp distress, bloody diarrhea, bloody exudates, hematuria, tissue edema, incomplete rigor mortis (so blood and edema everywhere and weird half rigor mortis)
if you think you have encountered anthrax, what should you do?CALL STATE VET--> double bagged iced sample of un-clotted blood and slides to lab, and/or the tip of their ear. QUARANTINE THE FARM. BURN TO ASHES OR BUSY (but careful of ashes flying/water table)