Food Animal Medicine- Diarrheal Diseases of Ruminants 2

wilsbach's version from 2016-02-13 15:03


Question Answer
what IS salmonella?Gram negative bacterium which is a Facultative intracellular anaerobe
most salmonella dz is...(clinical/acute/subclinical/chronic...pick a word)subclinical
what are the two most common strains of salmonella which cause dz in cattle?Salmonella Typhimurium and Dublin are the most common types in cadle
which salmonella strain is host adapted to cattle, and which is able to attack many hosts and is a potential zoonosis?HOST ADAPTED: Dublin (think dubliner cheese- and you can only make that cheese from cows, not humans). POTENTIAL ZOONOTIC: Typhimurium
just a little small mention, but whats up with salmonella newport?she said there has been an inc in freq. often multidrug resistant-- so kinda scary
which salmonella can be transmitted vertically?S. dublin (bc it's host adapted, its more into the hosts ways of getting hostly sick of hostness)
how is salmonella transmitted?(1) **fecal-oral (animal to animal or from contaminated feed/pasture/water). (2) IF S. DUBLIN: vertical xmission
explain the pathophysiology behind salmonellosisOrganisms attach to enterocytes (if there is GI stasis or disruption of normal flora, it makes it even easier for them to attach), and then they penetrate the penetrate the microvilli and tight junctions. This stimulates an inflammatory response in the lamina propria, and the bacteria are engulfed by macrophages and neutrophils which then travel to the mesenteric LNs and Peyer's patches. They develop Secretory and malabsorptive diarrhea, and can cause thrombi which can lead to tissue damage. They also release endotoxins
WHO is most likely to get salmonella?Disease tends to occur in young, old, or debilitated animals....Or transitioning fresh cows (recently calved)
incubation for salmonella is how long?1-9 days (Or recrudescence from carrier state)
what is the duration (and average duration) of salmonella infection? is it eliminated?Duration 3-20 days (avg 5d). 10-20% become chronic or latent shedders
what is a good way to differentiate salmonella diarrhea from johne's diarrhea?SALMONELLA FECES HAS BLOOD AND FIBER IN IT. johnes doesnt
what are the clinical signs of acute salmonellosis?Endotoxemia, Bacteremia in severe cases, Watery, fetid diarrhea (blood, mucus, fibrin casts), abortion, dec milk production
what are the clinical signs of a chronic salmonella infection?Weight loss, ill-thrift, intermittent fever/diarrhea
which salmonella can cause PNEUMONIA in calves?S. Dublin (host adapted= can go more places in host)
how do clinical signs in calves vary between S. Dublin and S. Typhimurium?(remember dublin is host-adapted) DUBLIN: (6 weeks): pneumonia, bacteremia, diarrhea..... S. Typhimurium (2 weeks): enteric lesions
what does clinpath look like with a salmonella infxn?Neutropenia and lymphopenia (bc endotoxemia), Hyperfibrinogenemia (this is inflammatory response in rumis!)
what is the gold standard dx for salmonellosis?Fecal culture- but you should do at least 3x because Carriers may only shed intermidently. might also need selective enrichment
what are some ways you can dx salm.?(1) GOLD STANDARD= FECAL CULTURE. (2) Fecal PCR (3) ID of serotype (NVSL) (4) ELISA
tx: what is some supportive care you can provide?Intravenous fluid therapy, Endotoxemia
*when do you give antimicrobials for salm.? what can you give?***IMPORTANT: antimicrobials will not clear a carrier state and are not given to treat Salmonella!!!* they are given for For bacteremia/translocation only. you can give Ceftiofur, florfenicol
what are some prevention and control methods you can do for salmonella?Maintain a closed herd, Minimize stress, Separate maternity and sick pens, Separate calf housing from adults, BIOSECURITY, Beware water and feed sources, Detection of carriers: ELISA, culture, PCR
is there a vx for salmonella?yes
what should you know about the salm vx?Does not stop infection!!!! but Can reduce the severity of infection. *Need to use with other preventive measures. Use colostrum from vaccinated dams!
what is MDR salmonella, why do we care?this is MULTIDRUG RESISTANT salm. (MDR S. Newport present in 27 states!) Cattle often primary host reservoir (horses esp sensitive). It is a Nosocomial (originating in hospitals) disease, it is a Zoonotic disease, and is an issue with Food contamination (Higher in ground beef and pork)

Clostridium perfringens

Question Answer
CP type A is what dz?Possible causative agent of hemorrhagic bowel syndrome, yellow lamb dz
CP type B is what dz?Lamb dysentery (Britain, South Africa)
CP type C is what dz?Neonatal hemorrhagic enterotoxemia, necrotic enteritis, struck
which CP is a neonatal dz, and why?--* LESS THAN 10D OLD Type C (Neonatal hemorrhagic enterotoxemia, necrotic enteritis, struck) and it only really affect neonates bc this one is degraded by trypsin so once the stomach is acidified like in adults, this one can't survive and cause dz
CP type D is what dz?Enterotoxemia, Overeating disease, Pulpy kidney disease
enterotoxemia is caused by which type of CP? how does it infect animals/what are it's toxins?Clostridium perfringens type D, which is a NORMAL INHABITANT OF THE GI TRACT! it makes both Epsilon (and alpha) toxin which is ACTIVATED BY TRYPSIN which is why it is seen in mature animals
which rumis are most prone to enterotox (CPD)Sheep > goats, cattle
which clostridium affects adults and why?CP D because the epsilon toxin it produces is ACTIVATED by trypsin (interesting, because CP C only affects neonates bc it is ACTIVATED by trypsin)
what is the typical hx of a C. perfringens enterotoxemia?Well-fed rapidly-growing lamb acutely deteriorates in a matter of hours (very peracute)
what is the pathophys of CP enterotox (which strain is this again?)strain D. Heavy grain feedings or very rich pasture-> Type D prototoxin elaborates and is activated (basically cleaves it and turns it on)-->Epsilon toxin increases intestinal permeability--> Edema of lungs, kidney, brain
which CP is epsilon toxin?CP D (enterotox)
"pulpy kidney dz" is?CP D (enterotox, epsilon toxin)
If you see an animal that is just found acutely dead, you should think..clostridium sp!
clinical signs of enterotoxemia?(CP D) Animals are often found dead. Live animals may have signs relating to disease of...GI, renal, neuro
(enterotoxemia) clinical dz in SHEEP usually presents as..Lethargy, neurologic signs, death, minimal diarrhea
(enterotoxemia) clinical dz in YOUNG GOATS presents like..usually peracute with diarrhea, severe colic, fever, death
(enterotoxemia) clinical dz in MATURE GOATS (or if there is a feeding change) presents like..usually acute (young is peracute) with diarrhea, colic, dehydration
how is clinpath looking with enterotoxemia?Dehydration, azotemia, leukocytosis, Hyperglycemia, glucosuria
what is a huge hallmark sign of enterotoxemia?GLUCOSURIA!! because CP D damages the kidneys with epsilon toxin (pulpy kidney dz) and also stress hyperglycemia
what will you find on necropsy with enterotoxemia?enterocolitis, pulpy kidney, hydropericardium, encephalomalacia
is it useful to culture CP D?no....bc normal animals can have this in their GI
what is the best way to test for CP D/enterotoxemia?ELISA for the epsilon toxin (the actual cause of the systemic dz) or PCR for toxin-producing bacterial genes
how do you tx enterotox?IV fluids, bicarbonate, electrolytes, Type C & D antitoxin (5-100 mL parenterally (15-20 mL/goat) ), NSAIDs, antibiotics (Parenteral penicillin, Oral sulfas)
which abx for enterotox?Parenteral penicillin, Oral sulfas
prog of enterotoxemia?guarded
how can you try to PREVENT CP D?(enterotoxemia) Avoid high grain feedings (esp rapid inc in them)
is there a vx for enterotox?yes
who is the vx for enterotox best in?More protective in sheep than goats. CD-T vaccine better protection than multivalent