المحاضرات التأهيلية لاختبارات الوظائف الحكومية اليوم الاول

1. Differential diagnosis
A-Bacterial infection
1-Johne’s disease
Caused by an acid fast bacillus (Johne’s bacillus)
ccc. by much thickening and corragation of the
intestinal mucous membrane
The condition is locally confined to the affected intestine
and mesenteric l.ns with out purulent or caseous foci
Johne’s bacillus can not inoculated into G. pig or rabbits
and vica versa in T.B

2. Differential diagnosis
2-actinomycosis or actinobacillosis
It is difficult to differentiate two conditions from T.B., if no
lesions in tongue or maxilla.
Early lesions appear as shot like ,glistening hard
projecting nodules at the prephary of the node
L.ns are firmer…………. white fibrous C.T.

3. Differential diagnosis
3-bacillary necrosis of the liver
ccc. by absence of lesions from portal L.ns.
4-metastatic suppurative foci in the organs due to
pyaemia
*ccc. by absence of caseation and calcification
*absence of T.B lesion in L.n & presence of pyaemic
symptoms

4. Differential diagnosis
5-Brucella suis infection in pigs
Ccc. by originate in the inter –vertebral space
as sacro-lumber regions and extend to bodies of the
vertebrae
Rarely occur in the carcase l.ns
There is no involvement of the visceral organs
6-nodular necrosis
Cheesy necrotic foci in superficial muscle, specially tail
it does not involve the viscera and l.ns
T.B. is rarely in muscles

5. Differential diagnosis
B-Parasitic affection
1-Degenerated cysts (Echinococci) :
Ccc. by caseous or gritty centers can be easily squeezed
out leaving intact cyst
L.ns are free from any lesions
Microscopically examamination…………. hooklets
2-linguatula
Larvae found in l.n with greenish degenerated mass

6. Anthrax
It is septicaemic disease→ affect all animals +man
Infection most common among butcher →wounds or
abrasion →malignant pastille red swollen finger or →by
inhalation →wool sorter’s disease.
Judgment:
*all infected animals or suspected one →destroyed at six
feet deep →burning or burial
*condemn the hides, fat, blood and internal organs
*condemn the other carcases slaughtered in same hall

7. Actinobocillosis (wooden- tongue(
*it caused by Actinobocillus lignieresi bacteria
*lesions are most common in tongue and
muscles of the jaw appear as fibrous tumors
with purulent foci.
Judgment:
*the man →cannot infected via meat.
*condemn the effected organs → head ,stomach or liver.

8. Actionmycosis (lumpy Jaw(
*Caused by Ray fungus (Actinomycis bovis) →in
cattle →Lumpy Jaw In pigs →chronic mastitis in
saws
*The man can acquired infection from same sources in
nature that animals acquire it →not from meat ,accidental
, inoculation or animals
Judgment
In cattle→ condemn the affected organs
In saws → condemn the affected portion of mammary
gland

9. Caseous lymphedenitis
Chronic disease of sheep →caused by corynebactrium-
pseudo tuberculosis .
*Ccc. by Caseous purulent foci →in organs & L.ns
Judgment :
*condemn the affected parts
*Condemn whole carcass if generalized or associated
with emaciation

10. Foot and mouth disease
(aphthus fever(
It is in acute and highly contagious disease of cloven
animals
Disease →trans .to man through consumption of milk
and milk product but not through consumption of meat
Due to a powerful destroying effect of lactic acid
on the virus
The disease →common among butcher through wounds
or abrasions of their hands → during slaughter or
skinning

11. Foot and mouth disease
(aphthus fever(
Judgment :
*if there is no fever→ condemn the head, stomach,
intestines, lungs, udder and feets.
*The carcase should be passed after 24hrs.
*Peracute cases → may be passed for food if well bled
In spreading the disease by but danger bone marrow or
other infected tissues.
Can persist in bone marrow for months

12. Rabies
It is a dis. of dogs can infect other animals via biting
Judgment
 Rabies not transmission to man through consumption
of meat. The transmission to man occur by inoculation
during handling of meat.
 Animal without symptoms.→ harmless → pass for
consumption and condemn nerves connected with
udder, pancreas, C.N.S., salivary gland bite.
 Animal with symptoms. → condemn the whole
carcase

13. Brucellosis
It is cause contagious abortion → in cattle
Infectious abortion → in goat and saw
Brucella suis
Organism in swine give rise to lesions in vertebra and
joints and bursae like T.B.
In spleen form chronic nodular formation up to1/6 inch
in size have yellowish white contents may be tinged
with light green

14. Brucellosis
Br. abortus (undulant fever)→ brucellosis in man
Ccc. by fever with recurrent irregular temperature
infection → occur by drinking milk or inoculation via
handing of infected meat or animals
Does not occur through → consumption the meat of
infected animals

15. Brucellosis
Br. meletensis
Highly infective to man via consumption of goat milk or
products
Air –borne infection from faeces, dust
Via contact with infected flocks
Br. meletensis and Br. Suis are more pathogenic for man
than Br. Abortus

16. Brucellosis
Judgment
Brucella→ easily destroyed by lactic acid still viable for
a short time in the muscles
Brucella can resist the refrigeration for excess one
month
Can resist the pickling and inadequate smoking
Carcase affected with brucella pass for consumption
after condemnation of lungs ,liver, spleen, kidney,
intestine, udder, blood and carcase L.ns
Carcase affected with localized lesions of brucellosis
Passed after remove and condemn the affected parts

17. Pox (variola(
*the term variola applied to a class of contagious
diseases.
It is ccc. by fever and vesico-pustular lesions
The blood and lymph are not virulent unless they are
taken from lesions.
Judgment
If carcase slaughtered during develop of pox condemn
If temperature of animal returned to normal+ pox are
healed carcase may pass for food

18. Tetanus (lock jaw(
*It is an acute dis. caused by clostridium tetani
(anaerobic spore forming bacillus)
Judgment
Affected carcase cond. although there are no danger in
eating or handling of infected meat but carcase are
badly bled setting rapidly putrefied.

19. Rift vally fever (RVF(
RVF or enzootic hepatitis is an acute arthropod born
viral disease that affect several species of animals
mainly sheep, cattle and goats
The disease is caused by an arbo virus of the
phlebotomus fever group
The disease was investigated among sheep of the rift
vally of Kenya.
the virus produces 70-100%mortality in calves and
lambs of less than 7 days of old age but only 10-20%
in adult animals

20. Rift vally fever (RVF(
The most clinical sing in adult animals is
abortion.
In Egypt causing extensive morbidity and mortality in
humans and domestic animals.
Humans become infected especially by contact with
infected animals and carcases.
In some severely affected areas about70% of the human
population wear infected with signs of encephalitis,
blindness and hemorrhagic fever at least

21. Rift vally fever (RVF(
*In natural infection, the blood as well as the liver and
spleen contained the virus at the time of fever or death
*Also the only sign of the disease in many ewes is
abortion
*The primary lesion in RVF is focal hepatic necrosis
Judgment
Total condemnation of RVF carcase.