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Flashcards in Past Exams 2008/2010 Deck (115)
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____________________ is a clostridial organism that causes enteric infections subsequent to antimicrobial therapy.

Clostridium difficile


__________________________ is an organism that causes rhinitis, tracheobronchitis and occasionally pneumonia in cats (probably in association with a viral agent).

Bordetella bronchiseptica


___________________________ is a cause of contagious epididymitis in rams and abortion and decreased fertility in ewes.

Brucella ovis


___________________________________ is a common cause of enteritis in humans and abortions in sheep

Campylobacter jejuni


___________________________________ is a facultative anaerobic organism that causes granulomatous, tumor like lesions primarily in the head and neck area of cattle.

Actinobacillus lignieresii


___________________________________ is an organism that causes acute inflammation of the nasal turbinates, acute air-sacculitis, swelling of the head and wattles, decreased food intake and a marked loss in egg production in egg-laying chickens.

Haemophilus paragallinarum


___________________________________ is a difficult to culture organism that is transmitted venereally but which has been eradicated from the U.S. horse population

Taylorella equigenitalis


___________________________________ is an organism that causes tracheobronchitis and chronic paroxysmal coughing and toxemia in humans. It is most damaging to infants under 1 year of age.

Bordetella pertussis


___________________________________ occasionally infects wounds and is a cause of Apitting edema@.

Clostridium septicum


___________________________________ is a cause of enteritis and focal hepatic necrosis in laboratory rodents

Clostridium piliformae


________________________ is the name of the flaccid paralysis syndrome commonly observed subsequent to infection with Campylobacter jejuni

Guillain-Barre syndrome


___________________________________ and ___________________________________ are the two main causes of bacterial meningitis in humans.

Neisseria meningitidis

Haemophilus influenzae


___________________________________ and ___________________________________ are two organisms that cause disease in ruminants in association with swampy areas and liver fluke migration

Clostridium novyi type B

Clostridium hemolyticum


________________________________ is an organism that usually enters via a wound, tick bite, or through the conjunctiva of humans. It spreads from the regional lymph nodes to the liver, spleen, bone marrow, and lymphoid tissues, forming granulomatous nodules which tend to ulcerate.

Francisella tularensis`


___________________________________ is the cause of Aforage poisoning@ in horses.

Clostridium botulinum


___________________________________ is a cause of persistent bacteremia, epididymitis and testicular atrophy in dogs

Brucella canis


___________________________________ is the substance supplied to some Haemophilus species by a Staphylococcus nurse colony.



___________________________________ is an organism that causes ulcerative enteritis of the lower 1/3 of the intestine of a variety of wild and domestic avian species.

Clostridium colinum


____________________________________ is the currently used vaccine for prevention of brucellosis in cattle.



_____ is a clostridial toxin that produces liquefactive necrosis, edema and hemorrhage in the brains of sheep.

Clostridium perfringens epsilon toxin


________________________________ is the major toxin involved in infections with Fusobacterium necrophorum.



___________________________________ is the most pathogenic species of Brucella for humans.

Brucella melitensis


___________________________________ is the cause of undulant fever in humans.

Brucella abortus


______________________ is the test used to screen milk samples for Brucella abortus infected cows.

Milk Ring Test


Why do we not routinely perform bacterial cultures for Fusobacterium necrophorum?

It is almost always in mixed cultures, ie., it is difficult to isolate in pure culture. Also, most of the infections are reasonably characteristic and there is no need to identify specific bacterial agents involved. (It actually isn=t hard to grow, just hard to isolate; Grows on anaerobic blood agar plates).


List three diseases in which Pasteurella multocida is not primarily a respiratory tract pathogen. Also list the capsular type and host animal involved

Disease Capsular type Host animal

Fowl cholera A Domestic and wild birds

Cat and dog bite wounds D Cats and dogs

cHemorrhagic septicemia B&E Water buffalo, bison, cattle


Briefly describe the mechanism by which the leukotoxin of Mannheimia haemolytica causes a marked increase in the inflammatory reaction in pulmonary tissues

The leukotoxin is an RTX (pore forming cytolytic toxin) that is able to damage or lyse phagocytic cells which releases the hydrolytic enzymes of those cells onto the surface of pulmonary tissues


Briefly explain on an immunologic basis, why some of the clostridial immunizing products are toxoids and some are formalinized whole cells?

Formalinized whole cell products are used to protect against infection. Toxoids may only generate antibody to neutralize toxins that are produced by an organism. In some cases, antitoxic immunity is more important than protecting against infection because some of the toxins produce disease when present in very small quantities. In other cases it is most important to protect against infection, often because there might be multiple virulence factors or toxins produced.


Describe the pathogenesis of Adescending tetanus@.

Clostridium tetani is introduced into a wound in spore form. The spores germinate and the organism produces tetanospasmin (tetanus toxin). The toxin is absorbed by the blood and lymph and transported throughout the body. It acts as a protease and blocks neurotransmitter release (specifically glycine and gamma aminobutyric acid) at the level of the spinal cord and brain stem. It selectively acts on the inhibitory nerve network and results in spastic paralysis. The nerves supplying the muscles of the head and neck are affected first followed by the respiratory muscles


Explain briefly how you would generate Clostridium botulinum polyvalent antitoxin.

(NOTE: This one gave the class fits because nobody seemed to know what polyvalent means and many students couldn=t explain how to even get antitoxin at all. There are several different toxins, A, B, C, D, E, F, etc., that are all immunologically distinct. Since the disease is very acute and we don=t have time to do the necessary tests to determine the exact toxin involved, one needs antitoxin to neutralize all of them.

Polyvalent antitoxin has antibodies to all the common toxins.) Answer: Probably the best method would be to hyperimmunize one or more horses with toxoids representing each of the main Clostridium botulinum toxin types. Bleed the horses and titer the serum antibody against the toxins to make sure you have high titers against each of the toxins. Then combine the different antibodies into a single polyvalent antitoxin. Alternatively, one could hyperimmunize one or more horses with toxoids representing all the main toxin types (a mixture of toxoids).