Dr.Morka Amante
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Transcript of Dr.Morka Amante
ADDIS ABABA UNIVERSITYCOLLEGE OF VETERINARY MEDICINE AND AGRICULTURE
DEPARTEMENT OF PARASITOLOGY AND PATHOLOGY
TROPICAL VETERINARY PROTOZOLOGY
REVIEW ON NEOSPORA AND BESNOITIA
By: Morka Amante
The apicomplexan protozoan Neospora spp. is an obligate
intracellular parasite
Neospora caninum is a protozoan parasite infecting primarily
dogs and cattle
It is a globally distributed protozoan capable of infecting a wide
variety of hosts
N. caninum, is a more frequent cause of abortion and stillbirth in
intensive and semi-intensive dairy production in Ethiopia than
the BVD virus and the Brucella bacterium(Asmare,2014).
INTRODDUCTION
NEOSPOROSIS
• Niosporiosis is diseases of protozoan neospora spp which is an obligate intracellular parasite
Etiology• Neospora caninum and Neospora hughesiHost range• dogs, coyotes, and dingoes as definitive hosts for
Neospora caninum and Neospora hughesi• cattle and other ruminants, canines, pig and horses as
intermediate hosts• Horse intermediate hosts for Neospora hughesi• Site infinal host=s.intestine• Site in I.host= schizont indotelial cells of blood vessel,
large cyst containig bradyzoites found in muscle
life cycle
Life cycle of Neospora caninum(slide share)
N. caninum has a worldwide distribution seroprevalence reported in Ethiopia by
Asmare (23.8%). Transmission Horizontally = by the ingestion of oocysts
in feces, Bradyzoites in tissue cysts vertically = transplacental route Neospora caninum DNA has been reported
in bovine semen may be other route
Epidemiology
The risk factors for infection are largely unknown but
evedence suggest that
close contact of cattle with dogs
High stocking densities
Management factors and
concurrent diseases that lead to immunosuppression
may also be important risk factor
Risk factor of the diseases(neosporosis)
Definitive host: Dogs are the final host and sexual phase
occur in them
Intermediate host: Cattle are the major intermediate hosts
and asexual reproduction phase occur in them = from dam
to calf in utero and lactogenically, Infection of cattle can
also occur from the ingestion of food or water
contaminated with dog feces containing Neospora caninum
oocysts = cause of abortion in cattle
Pathogenesis
Tachyzoites penetrate host cell like central nervous
system, muscles, macrophages and other cells, where
they divide rapidly.
Tachyzoites can also be transmitted either with
contaminated food and water or transplacentally to the
fetus in pregnant animals
Tissue cyst containing bradyzoites that these are found only in the nervous system
Cont..
Neosporosis causes
stillbirth
fetal resorption
mummification
Calves are born with neurological symptoms(unable to
stand, unable to suckle, domed skull and torticollis)
abortion and decreases in their milk production
Clinical findings
Effects on production direct cost are dueto abortion Infertility returns to service and loss of milk yield indirect costs through replacements.
Economic importance of the diseases
(IFAT) (ELISA) Histopathology of fetus
Diagnosis
Treatment
No effective drug or vaccine available Suggestions to reduce incidence:
◦Remove all cows infected with Neospora◦Test replacement heifers and newborn calves
◦Reduce stressors (low quality feed stuffs, overcrowding and excessive heat)
◦Prevent horizontal transmission by preventing fecal contamination of cattle feed
Besnoitia spp are a protozoan blood parasite which
causes skin disease in cattle.
The first recorded cases of bovine besnoitiosis were
described in southern France by Cadeac (1884) and by
Besnoit and Robin (1912) in cattle Cause Bovine besnoitiosis (also referred to as bovine
elephantiasis and bovine anasarque) besnoitiosis is either a severe but usually non-fatal
disease of cattle, or a mild clinical disease.
BESNOITIA
Besnoitia are protozoan parasite with classified 9 species, which only 2 of these species are important in livestock animals
species
Etiology
B. Besnoiti B. darling B. tarandiiB. caprae B. Benetti B. Wallacei B. jellisoni, B. akadoni B. oryctofelis
The two common Besnoitia species of animal
Specie Affinity site Intermediat
e hosts
Definitive host
Besnoitia
besnoiti
Skin,
conjunctiva
Cattle Cat, wild cats
(Lion, leopard)
Besnoitia caprae Skin,
conjunctiva
Goats Cat, wild cats
(Lion, leopard)
The complete life cycle of the parasite remains unknown, although seasonal presentation of the disease (mainly in summer and in beef cattle while they are on pastures) suggests an important role for horizontal transmission by
either direct contact, through natural mating or through mechanical transmission by blood-suckling
arthropods
life cycle
Disease occur as outbreaks in tropical and subtropical countries
and sporadically in other countries
Bovine besnoitiosis is common in Africa, Asia and in the South
of Euroup
Caprine besnoitiosis in Keny a, Uganda, Iran, and Kazakhastan
Many aspects of the epidemiology of bovine besnoitiosis remain
uncertain including prevalence and incidence of infection and
disease in endemic areas, routes of transmission and risk-factors
associated to infection and disease
No reported diseases in Ethiopia
Epidemiology
Following infection in cattle or in goats, the tachyzoites proliferate in macrophages, fibroblasts, and endothelial cells and causing vasculitis.
they develop to form bradyzoite cysts in fibroblasts in the derm is, subcutaneous tissues, fascia, nasal and laryngeal mucosa
After developing cysts in the skin, painful subcutaneous swelling, thickening of the skin, alopecia, and necrosis can be occur
Sterility in males is caused by a necrotizing orchitis. Death may occur in both the anasarca and scleroderma stages of the disease, regardless of the sex of the animal
Pathogenesis
In bovine besnoitiosis
The acute anasarca stage
include fever, increase in pulse and respiratory rates,
painful swelling on the ventral aspects of the body, edema
of the skin, sometimes diarrhea, lacrimation and nasal
discharge
The chronic scleroderma stage
mainly associated with cyst formation In chronic stage,
there is a severe dermatitis over most of the body
Clinical findings
In Caprin besnoitiosis
Thickening of the skin over the lower limbs , around the
eyes, nose, face and scrotum, alopecia in all of these areas,
and
white granular cysts in the sclero-conjunctiva can be seen
Cont……
Horizontal transmission is probably the main method of
transmission of infection =occurs as a consequence of
direct contact among animals with wounds or
lacerations
infected bulls in natural mating
mechanically by blood-sucking arthropods, such as
horseflies and deer flies
bovine besnoitiosis has not been reported to infect
humans.
Transmission of besnoitiosis
Seasonality factors= majority of new cases occur during
the warmer, moister months of the year
Age factors =The highest incidence of infection was
detected in adult animals on a farm where the disease was
present, but was rarely encountered in calves under 6
months of age
Sub-clinical carriers as factor= The existence of blood-
sucking flies could be a risk factor for the rapid spread of
the disease
Risk factors for besnoitiosis
disease causes a serious illness both during the acute and
chronic phases that could compromis animal welfare
Bovine besnoitiosis leads to significant economic losses by
a decline in milk production,
sterility,
transient or permanent infertility of bulls,
skin lesions and increase of mortality in affected cattle
population
Economic and welfare impact of besniotiosis
Besnoitiosis can be diagnosed by demonstration of B.
bradyzoites in skin biopsy smears or scleral conjunctival
scrapings
A number of diagnostic tests such as
cytology
histopathology
serology and PCR testing are available
Diagnosis of besnotiosis
there are not any effective drugs(no known treatment)
for this disease or vaccines available
a live-attenuated vaccine has been used(s. Africa and
Israeli).
Control is effected by the elimination of infected
animals and carriers, and early diagnosis
Treatment and Control of besniotiosis
THANK YOU