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Journal of Veterinary Advances
Clinical Signs of Experimental Trypanosoma evansi Infection in
Donkeys: Ameliorative Effects of Isometamidium chloride and
Buparvaquone Treatments
Garba U. M., Sackey A. K. B., Lawal I. A. and Esievo K. A. N.
J Vet Adv 2015, 5(4): 891-901
DOI: 10.5455/jva.20150413121927
Online version is available on: www.grjournals.com
GARBA ET AL.
ISSN: 2251-7685
Short Communication
Clinical Signs of Experimental Trypanosoma evansi
Infection in Donkeys: Ameliorative Effects of
Isometamidium chloride and Buparvaquone
Treatments
1
Garba U. M., 2Sackey A. K. B., 3Lawal I. A. and 4Esievo K. A. N.
1
Veterinary Clinic, Equitation Dept, Nigerian Defence Academy, Kaduna, Nigeria.
Department of Veterinary Medicine, Faculty of Veterinary Medicine, Ahmadu Bello University Zaria, Nigeria.
3
Department of Veterinary Parasitology and Entomology, Faculty of Veterinary Medicine, Ahmadu Bello University Zaria, Nigeria.
4
Department of Veterinary Pathology, Faculty of Veterinary Medicine, Ahmadu Bello University Zaria, Nigeria.
2
Abstract
Trypanosoma evansi (T. evansi) infection causes a progressively wasting and ultimately fatal animal
trypanosomosis mainly in camels, horses, donkeys, zebra, mules and cattle in Africa, Asia, Middle East and
South America resulting in reduced traction power and annual death of thousands of affected animals. The aim
of this study was to evaluate the ameliorative effects of Isometamidium chloride (standard trypanocide) and
Buparvaquone (anti-theilerial drug) treatments on the clinical signs of T. evansi infection in donkeys as part of
study on the efficacies of the drugs against T. evansi infection. Twenty four apparently healthy donkeys were
used for the experiment. The animals were housed, fed on hay and concentrate feed, and water was provided
adlibitum. Animals were identified with neck-tags and grouped into 4 namely; groups A1, A2, A3 (T. evansiinfected groups) and B (control) of 6 animals each (3 males and 3 females) at random. Two milliliters of
buffered, parasitaemic Wister rat blood containing 2.0x106 of T. evansi (Sokoto isolate) was used to infect each
of all donkeys in the ‘A’ category through jugular vein. On day28 post-infection, groups A2 and A3 animals
were treated with Isometamidium chloride and Buparvaquone respectively. Groups A1 and B remained as
Infected-Untreated and Un-infected-Untreated respectively. Animals were monitored and evaluated postinfection and post-treatment for clinical signs including vital parameters and body weight changes. The effects
of treatments on the observed-parameters were evaluated. Result showed that T. evansi infection in donkeys is
predominantly a chronic disease, with an incubation period of 3-7 days. Isometamidium chloride treated group
showed greater reduction in prevalence of signs than buparvaquone treated group which did not differ much
from the Un-treated group. It was concluded that Trypanosoma evansi infection in donkeys is a chronic disease
and treatment with Isometamidium chloride, ameliorates the clinical signs while buparvaquone does not.
Keywords: Ameliorative effects, buparvaquone, clinical signs, donkeys, isometamidium chloride, trypanosoma
evansi, infection.
Corresponding author: Veterinary Clinic, Equitation Dept, Nigerian Defence Academy, Kaduna, Nigeria.
Received on: 04 Mar 2015
Revised on: 14 Mar 2015
Accepted on: 13 Apr 2015
Online Published on: 30 Apr 2015
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J. Vet. Adv., 2015, 5(4): 891-901
CLINICAL SIGNS OF EXPERIMENTAL TRYPANOSOMA EVANSI INFECTION IN …
Introduction
Trypanosoma evansi infection causes a
progressively wasting and ultimately fatal animal
trypanosomosis mainly in camels, horses, donkeys,
zebra, mules and cattle in Africa, Asia, middle East
and South America resulting in great economic
losses due to reduced traction power (ILRI, 1997)
and annual death of thousands of affected animals
(Mihret and Mano, 2007). Other animals affected
are dogs and pigs (OIE, 2004).
Trypanosoma evansi infection is referred to
with over 30 different ethnic terms which describe
the chronic devastating outlook of infected camels
and equids in different geographical regions of the
world as reviewed by Hoare (Stephen, 1986) such
as surra in Asia (OIE, 2004) which is an Indi word
meaning ‘rotten’ (Vittoz, 1955), El-debab in
Algeria (Atarhouch et al., 2003), Mbori in Sudan,
Guifar in Chad and Pmenchaca amongst Tuaregs of
Niger (Antoine-Moussiaux et al., 2007). Successful
cure and consequently, amelioration of the
accompanying signs of surra is affected by the
problem of reported cases of resistance by T. evansi
strains to the available range of trypanocides
namely; Diminazene aceturate, quinapyramine,
cymelarsan (De Koning, 2001; Suswam et al.,
2001) and suramin (FAO, 2012) in different
countries (El Rayah et al., 1999; Zhou et al., 2004).
In this study, the clinical signs of Trypanosoma
evansi infection in donkeys were collated as they
emerged and the ameliorative effects of treatments
using Isometamidium chloride; a standard
trypanocides (Shapiro and Englund, 1990: Aliu,
2007) and Buparvaquone; an anti-theilerial drug
(Dhar et al., 1987; Mutugi et al., 1988) were also
evaluated as part of study conducted on the
efficacies of Isometamidium chloride and
buparvaquone in the search for drugs with efficacies
against Trypanosoma evansi infection in donkeys.
Materials and Methods
Experimental Animals
Twenty four apparently healthy donkeys
comprising of 12 males and 12 females were used.
The experimental animals were between 11 and 15
months old as estimated in the animal market prior
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to purchase using eruption and wear features of the
incisors teeth described by Wayne and Melvin
(2000) and Joe (2012).
Housing and Acclimatization of Animals
Topical sweat-resistant fly-repellant spray
containing pyrethroids (Endure®, Farnam co. inc.,
USA) was applied on the animals as recommended
by the manufacturer, to keep flies off the animals
prior to housing. The animals were housed in
prepared and fly-proofed pen in the Department of
Veterinary Parasitology and Entomology, Faculty of
Veterinary Medicine, Ahmadu Bello University
Zaria, where the experiment was conducted. Zaria
city is located in North Western, Nigeria
(Geographical coordinates of Zaria; 11° 4' 0" North
and 7° 42' 0" East). The experimental animals were
acclimatized for 14 days (Wolfensohn and Lloyd
(2013).
Pre-Infection Evaluation of Experimental
Animals
During the acclimatization period, the animals
were examined for external parasites, 5g faecal
sample was collected per rectum into labeled
polyethene bags and examined for gastrointestinal
parasites using floatation and sedimentation
methods (Charles, 2007).
The
animals
were
dewormed
using
Fenbendazole bolus (Fenacure®, Ashish Life
Sciences PVT ltd, India) at the dose rate of 10mg/kg
bd wt orally, once (Aliu, 2007).
Four milliliters (4mL) of jugular vein blood
was collected from each donkey using 10mL
syringe and 19G X 11/2 inch needle (Weiser, 2012;
Wolfensohn and Lloyd, 2013). Three milliliters
(3ml) of the blood was anti-coagulated in EDTA+k3
(2mg/mL of blood) bottle which was used to
prepare 2 Giemsa stained thin blood smear slides
and 2 haematocrit centrifugation technique (HCT)
tubes (Wosu, 2002) from each samples and were
examined at x100 objective, across 20 light
microscope fields. The balance of 1ml collected
blood from each donkey was immediately used for
mice inoculation test (MIT). Two (2) representative
mice per donkey were each inoculated with 0.5ml
of donkey’s blood per mouse using 1ml sterile
disposable syringe with 29G X ½ inch needle intraJ. Vet. Adv., 2015, 5(4): 891-901
GARBA ET AL.
peritoneally as support test for direct microscopy.
Inoculated mice were monitored for parasitaemia at
48 hours intervals for 2 weeks using collected tail
blood and examined on Wet Film and HCT (OIE,
2010) to ensure that the experimental donkeys were
haemoparasites-free.
Feeding of Animals
The animals were provided with feed materials
equivalent to 5% of their mean body weight in
forms of Sorghum/Maize stovers, grass hay and
legume hay in the ratio 4:1 while the concentrate
feed consisted of a mixture of coarsely ground
sorghum grain, bran, and dried groundnut cake
which was served daily in two divided rations for
morning and evening. Multi-minerals/vitamins lick
blocks and clean drinking water were provided adlibitum (Aganga et al., 2000).
Identification and Grouping of Animals
Animals were identified with seriallynumbered neck-tags and assigned to experimental
groups of 6 animals (3 males and 3 females) each at
random, namely; groups A1, A2, A3 and B (Aviva
and Poul, 2013).
Baseline Data Collection
Baseline data was collected on respiratory rate
(costo-abdominal movement), pulse rate (pulsation
of External Maxillary Artery), rectal temperature
and body weight of the animals at 7 days intervals
over 28 days period (Wosu, 2002). Body weights of
the donkeys were determined using sling scale as
reported by FAO (2014) and all parameters were
evaluated between the hours of 06.00 and 08.00
local time, prior to provision of feed in order to
minimize the influence of gut-fill on body weight
values (De Aluja et al., 2005).
Propagation of Trypanosoma Evansi
Trypanosoma evansi originally isolated from
camel in Sokoto, Nigeria (Sokoto isolate) and
maintained in Wistar rats in the Department of
Veterinary Parasitology and Entomology, Ahmadu
Bello University, Zaria, was propagated in rats to
obtain sufficient inoculum. To achieve this, 1mL of
highly parasitaemic blood (determined on Wet
Blood Film) was collected from an infected Wister
rat via ocular vein into heparinised sample bottle
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J. Vet. Adv., 2015, 5(4): 891-901
and diluted with 1mL phosphate buffered saline
glucose solution to obtain 2mL inoculum.
Immediately, 4 donor rats were inoculated each
with 0.5mL of the inoculum, intra-peritoneally
using sterile 1mL disposable syringe, 25GX 11/2
inch needle (Wolfensohn and Lloyd, 2013). The 4
rats were monitored for parasitaemia levels at 48
hours intervals using tail blood for Haematocrit
Centrifugation Techniques (HCT) test. Twelve days
post-inoculation, 3 of the 4 rats had attained +4
(>20 parasites per microscope field) while 1 rat had
+2 (6-10/field) parasitemia levels. The donor rats
were sacrificed and their blood pooled into a sterile
conical flask containing heparin sodium 20
Units/mL of blood. A total of 15mL of pooled blood
was obtained, the parasitemia was re-evaluated
using haemocytometer (Elaine and Margi, 2007),
then diluted with phosphate buffered saline glucose
solution to obtain about 1.0 x106 T. evansi /mL of
inoculum (Monzon et al., 1990).
Experimental Infection of Animals
The prepared inoculum was immediately
injected at the rate of 2mL (containing 2.0x106 T.
evansi) into each of the experimental donkeys in
groups A1, A2 and A3 through jugular vein and the
day of infection was considered as day0 of
infection. Group B remained as Un-infected
(control) group.
Post-Infection Monitoring
Post-treatment, the infected animals were
monitored over 28 days period as follows;
From day1 to day7; the animals were
monitored daily while from day8 to day28; the
animals were monitored twice per week for
parasitemia levels using ear vein blood examined on
HCT (OIE, 2010; FAO, 2014) and scored according
to Woo (1970) technique to ensure establishment of
infection in the infected groups of animals. Clinical
signs, including respiratory rate, pulse rate and
rectal temperature were also evaluated as described
by Wosu (2002). Body weight was evaluated at 7
days intervals during the post-infection monitoring.
Treatment of Specific Infected Animals
On day 28 post-infection (PI), groups A2
animals were treated with Isometamidium chloride
(Securidium®, Laprovet, France) 1% solution at the
CLINICAL SIGNS OF EXPERIMENTAL TRYPANOSOMA EVANSI INFECTION IN …
dose rate of 0.5mg/kg bd wt by deep intramuscular
injection once while group A3 were treated with
Buparvaquone (Butalex®, Coopers K-brand Ltd,
Kenya) 5% w/v at dose rate of 2.5 mg/kg bd wt by
deep intramuscular injection twice at 72 hours
interval respectively as recommended by the
manufacturers. Treatment day was considered as
day0 of treatment.
Post-Treatment Monitoring
Post-treatment (PT) monitoring of experimental
donkeys was conducted for 148 days during which
clinical signs were further evaluated daily from
day1-7, twice per week from day8-28 and at weekly
intervals from day29 -148. Body weight was
evaluated at 7 days intervals during the posttreatment monitoring.
Ethical Considerations
All procedures on the animals were performed
as recommended by the European Union ‘Directive
2010/63’ contained in the report by Wolfensohn and
Lloyd (2013) and approved by the Research and
Ethics Committee of Ahmadu Bello University,
Zaria, Nigeria.
Statistical Analysis
Group prevalence of clinical sign= Number of animals with the clinical sign in a group x100
Total number of animals in that group
Means of parameters were determined for
groups in all phases of experiments, tables and
graphs were prepared using Microsoft Excel 2010.
Analysis of Variance (ANOVA) was used to
compare means of variables between experimental
animals groups and within groups at 95%
confidence level, where P< 0.05 was considered
statistical significant (Mead et al., 2002).
Clinical Signs Observed in Trypanosoma
evansi Infection in Groups of Donkeys
The incubation period observed was 3-7 days
and pre-patent period of 3-4 days for experimental
Trypanosoma evansi infection in donkeys. The
clinical signs of infection were more pronounced in
Infected-Untreated group of animals and started
with mild pyrexia of 38.50C (control; 36.670C)
(Table 1).
Results
Table 1: Prevalence of clinical signs observed in donkeys experimentally infected with Trypanosoma evansi based on
infection and treatment status.
Clinical Signs
Post-infection (Day3 –
Post-treatment (Day1 – 148 PT;
28 PI)
equivalent to Day29-176 PI )
A1 (n=6) A2 (n=6) A3 ( n=6) A1(I-U,
A2
A3
n=6)
(I-Isomet,
(I-Buparv,
n=5)
n=5)
Mild pyrexia (38.50C, control; 36.670C)
6(100)
6(100)
6(100)
NA
NA
NA
Lethargy/Recumbency
6(100)
6(100)
6(100)
6(100)
NA
5(100)
Rough hair coat
3(50)
5(83.3)
5(83.3)
6(100)
NA
5(100)
Urticaria/alopecia on trunk
3(50)
4(66.7)
2(33.3)
2(33.3)
NA
2(40)
Prominence of ribs and hip bones
6(100)
6(100)
6(100)
6(100)
NA
2(40)
Pica appetite
6(100)
6(100)
6(100)
NA
NA
NA
Penile erection (in males)
3(100)
3(100)
3(100)
NA
NA
NA
Rectal prolapse
1(16.7)
1(16.7)
1(16.7)
NA
NA
NA
Pale ocular and oral mucosae (mild)
6(100)
6(100)
6(100)
NA
NA
NA
Intermittent diarrhoae
1(16.7)
NA
2(33.3)
NA
NA
NA
Bilateral seromucous epiphora
NA
NA
2(33.3)
NA
NA
2(40)
Isolation (seclusion)
NA
NA
2(33.3)
NA
NA
2(40)
Ventral abdominal oedema
NA
NA
NO
6(100)
1(20)
1(20)
Lymphadenopathy
6(100)
6(100)
6(100)
6(100)
NA
2(40)
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GARBA ET AL.
Morbidity
Mortality
6(100)
NA
6(100)
1(16.7)
6(100)
1(16.7)
-------1(16.7)
--------NA
-------NA
Post-infection (PI): Letter A1, A2 and A3 represented the T. evansi-infected groups of animal. Post-treatment (PT): A1 (I-U) =
Infected-Untreated, A2 (I-Isomet) = Infected and Isometamidium chloride-treated, A3 (I-Buparv) = Infected and Buparvaquonetreated groups. n= sample size in animals group and NA = Not applicable (the referred clinical sign was not observed in the
experimental group). Values in parentheses are percentages. Prevalence of ‘penile erection’ was based on the total number of male
animals in the groups.
Mean Respiratory Rate Changes
The mean respiratory rate was significantly
(P<0.05) elevated in all groups of animals infected
with T. evansi from day28 to 35 post-infection (PI)
and variously persisted to day56 PI.
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J. Vet. Adv., 2015, 5(4): 891-901
The isometamidium-treated group showed
decline in values not significantly different (P>0.05)
from pre-inf. value as as early as day35 PI. After
day56 rate returned to near pre-inf values (Fig 1).
CLINICAL SIGNS OF EXPERIMENTAL TRYPANOSOMA EVANSI INFECTION IN …
Mean Pulse Rate Changes
All groups of animals, irrespective of infection
status showed decline in mean pulse rate on day28
896
PI. The decline is apparently due to severe drop in
ambient temperatue from 24±2 0C to 19±20C during
the 1 week period (day 21-28 PI) (Fig 2).
J. Vet. Adv., 2015, 5(4): 891-901
GARBA ET AL.
Mean Rectal Temperature Changes
All T. evansi-infect groups of animals showed
increase in mean rectal temperature value from
day7 to 21 PI(2 weeks period) with peaks on day14
PI. Rectal temperature undulated (Fig 3).
Mean Body Weight Changes
All T. evansi-infect groups of animals showed
decline in mean body weight values from day7 to
21 PI(2 weeks period). Between day28 and 84 PI (8
weeks period), there was slight stability in mean
body weight at the levels of pre-inf. value which
were later, on day91 followed by a gradual decline
trend to end of PT observation (Fig 4).
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J. Vet. Adv., 2015, 5(4): 891-901
CLINICAL SIGNS OF EXPERIMENTAL TRYPANOSOMA EVANSI INFECTION IN …
Discussion
The Mild pyrexia and incubation period of 3-7
days may reflect the level of pathogenicity of the
parasite isolate (Habila et al., 2012). The classical
and non-specie specific signs (Gardiner and
Mahmoud,
1990)
observed
were;
lymphadenopathies due to immunologic response
by lymphoid tissue to the infecting T. evansi (Klaus,
1996), pale mucous membranes suggesting reduced
peripheral circulation as a result of anaemia in the
infected animals (Rickman and Cox, 1983). The
rough hair coat and urticaria might be due to
immune complexes deposition, tissue inflammation
and damages to organs (Enwezor and Sackey, 2005)
while the bilateral seromucous epiphora may partly
be due to entry of T. evansi into anterior chamber of
eye as reported in horses (Stephen, 1986) resulting
in inflammation (Enwezor and Sackey, 2005). The
lethargy, prominent hipbone/ribs and the isolation
behavior are the aftermaths of hypoglycaemia
(Habila et al., 2012), hypocalcemia because of the
role of calcium in muscle contraction (Bohn, 2012).
Other infrequent signs observed in acute phase were
persistent penile erection due to intravascular
coagulopathy as reported earlier in horses by
Lingard in 1893 (Stephen, 1986). The erection was
not due to libido because at the age of 11 to 15
months when they were used for the experiment, the
animals were not matured; until they attain 3-4
years of age (Starkey, 1995).
The
diarrhoae
was
precipitated
by
hypoalbuminaemia, and digestive disorders
(Allison, 2012) resulting in an increased fluidity and
volume of gut content and diarrhea. Also,
immunosuppression of the host animal by T. evansi
could allow flare of intestinal microflora such as
Salmonella serovars and Clostridium perfringens in
the colon and caecum and may precipitate
hypermotility of intestines resulting in decreased
transit time of intestinal content and diarrhea
(Stewart, 2013). The rectal prolapse might be due to
loss of rectal muscle tone during straining
associated with intermittent constipation and
diarrhoea (Stewart, 2013). Ventral abdominal
oedema observed in the chronic phase of the
infection in all groups of infected animals and more
severe amongst Infected–Untreated animals while
898
the Infected and treated with Isometamidium or
buparvaquone showed lower but the same severity
possibly due to treatment in the latter 2 groups
while the untreated group suffered full blown
disease (OIE, 2010) precipitated by parasitesinduced metabolic enzymes failure (Enwezor and
Sackey, 2005: Bal et al., 2012) and
hypoalbuminaemia with loss of vascular fluid to the
interstitial tissue especially in dependent areas
(Allison, 2012). The observed 100% morbidity
showed that T. evansi (Sokoto isolate) is pathogenic
to donkeys and the low mortality rate in acute phase
and the relapse observed in the chronic phase of the
study suggests that the course of surra in donkeys is
predominantly chronic if not treated or ineffectively
treated (Faye et al., 2001; Desquesnes, 2013). The
infected but Isometamidium chloride-treated
animals showed decrease in the over-all signs of the
disease in donkeys suggesting amelioration of signs
following clearance of parasitaemia by the drug
(Gutiérrez et al., 2013). The buparvaquone-treated
group of animals showed persistence of the signs to
chronic phase but with reduced prevalence
suggesting that there was no amelioration of clinical
signs by buparvaquone.
The hyperpnoea observed in all infected groups
of animals is apparently compensatory and
accompanied T. evansi-induced anaemia which
reduced available haemoglobin to transport oxygen
to tissues resulting in tissue anoxia (Gardiner and
Mahmoud, 1990). The isometamidium chloride
treated animals showed return of respiratory rate to
pre-infection level, a week post-treatment (PT)
suggests amelioration by isometamidium as against
persistence of hyperpnoea for longer period in
infected-untreated and buparvaquone-tread groups.
The genaral decline in mean pulse rate on
day28 PI suggest severe drop in ambient temperatue
(from 24±2 0C to 19±20C) during the 1 week period.
Although, only the buparvaquone-treatment group
showed significant tachycardia PI, there was
tachycardia in other groups too post-infection (PI) is
due to hypovolemia associted with anaemic
situation induced by T. evansi infection (Gardiner
and Mahmoud, 1990).
The pyrexia observed in all T. evansi-infect
groups of animals took a mild trend possibly due to
relatively low susceptibility of donkeys (Silva et al.,
J. Vet. Adv., 2015, 5(4): 891-901
GARBA ET AL.
1995;
Desquesnes
et
al.,
2013)
and
immunotolerance to T. evansi (Herrera, et al.,
2004). The absence of pyrexia in the chronic phase
of infection may be as a result of low parasitaemia
characteristic of chronic form of surra as in camel
(Rami et al., 2003; Wolkmer et al., 2009).
The decline in mean body weight values of all
groups of T. evansi-infected animals occurred sideby-side high parasitaemia which results in build up
of peroxides and free radicals in the body of
infected animal and damage all components of the
cell, including proteins and lipids (Murray et al.,
2003; Saleh et al., 2009, uptake of host glucose by
T. evansi for its matabolic activity (Maudlin et
al., 2004; Hunt, 2010) and parasites-induced
metabolic enzymes insufficiencies in the host
(Enwezor and Sackey, 2005) despite good appetite
resulting in progressive weight loss (emaciation)
and stunted growth in chronic form of surra (Omer
et al., 2007). Isometamidium treated group gained
weight suggesting amelioration. The infected
buparvaquone-treated and untreated groups
experienced gentle but steady weight loss in chronic
stage, perhaps due to persistence of pathogenic
parasite in the animals without amelioration of signs
resulting in un-abated metabolic failures and tissue
damages (Enwezor and Sackey, 2005).
Conclusion
The clinical course of T. evansi infection in
donkeys is partly acute but predominantly chronic.
Some of the acute signs include transient mild
pyrexia, hyperpnoea, tarchycadia, pale mucous
membranes, lethargy, urticaria with alopecia, low
mortality in acute stage, rarely observed signs are
penile erection, intermittent diarrhea and rectal
prolapse. The chronic signs include severe urticaria,
progressive emaciation or stunted growth, anaemia,
ventral abdominal oedema, recumbency and death.
Early
Isometamidium
chloride
treatment
significantly ameliorates all clinical signs of surra in
donkeys but buparvaquone does not significantly.
Acknowledgement
We are grateful to Prof. J.A. Natala; Head of
Department of Veterinary Parasitology and
Entomology, Ahmadu Bello University (A.B.U.),
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J. Vet. Adv., 2015, 5(4): 891-901
Zaria, Nigeria for approving the research animal
pen used as well as the technical staff of
Protozoology, Helminthology and Haematology
laboratories, Faculty of Veterinary Medicine,
A.B.U., Zaria for providing guidance in the
laboratories during the study.
References
Aliu YO (2007). Nigerian Veterinary Formulary; Handbook of
Essential Veterinary Drugs, Biologics and Pesticide
Chemicals. First edition, Vet. Counc. Nigeria., p. 67.
Allison RW (2012). Laboratory evaluation of the
liver/Laboratory evaluation of plasma and serum
proteins, In: Thrall MA, Weiser G, Allison RW and
Campbell TW, (Eds). Veterinary Hematology and
Clinical Chemistry. Second Edition, Wiley-Blackwell,
UK. pp. 401-424 and 460-479.
Antoine-Moussiaux NB, Faye B and Vias GF (2007). Tuaregs
ethnoveterinary treatments of camel diseases in Agadez
area (Niger). Trop. Anim. Health Prod., 39(2): 83-89.
Atarhouch T, Rami M, Bendahman MN and Dakkak A
(2003). Camel trypanosomosis in Morocco 1; result of a
first epidemiological survey. Vet. Parasit., 111(4): 277286.
Aviva P and W Poul (2013). Statistics for Veterinary and
Animal Science. Third edition, Wiley-Blackwell ltd, UK.
pp. 391.
Bal MS, Singla LD, Kumar H, Vasudev A, Gupta K and
Juyal PD (2012). Pathological studies on experimental
Trypanosoma evansi infection in Swiss albino mice. J.
Parasitic Dis., 36(2): 260-264. DOI: 10.1007/s12639012-0120-5.
Bohn AA (2012). Laboratory evaluation of electrolytes, In:
Thrall MA, Weiser G, Allison RW and Campbell TW
(Eds). Veterinary Hematology and Clinical Chemistry.
Sec. Ed., Wibey-Blackwell, UK. pp. 378-392.
Charles MH (2007). Internal parasites, External paraspites. In:
Charles MH and Margi S (Eds). Laboratory procedures
for veterinary technicians. Fifth edition, Mosby Elsevier
Inc., St Louis Missouri, pp. 187-252.
De Koning HP (2001). Transporters in African trypanosomes:
role in drug action and resistance. Int. J. Parasit., 31:
512-522.
Desquesnes M, Holzmuller P, Lai D, Dargantes A, Lun Z and
Jittaplapong S (2013). Trypanosoma evansi and surra: A
review and perspective on origin, history, distribution,
taxonomy, morphology, host and pathogenic effects.
(2013): ID-194176. pp. 22. Retrieved July 20, (2014)
from, htm:/dx.doi.org/10.1155/2013/194176.
Dhar S, Malhotra, DV, Bhushan C and Gautam OP (1987).
Chemoprophylaxis
with
Buparvaquone
against
theileriosis in calves. Vet. Rec., 120: 375.
Elaine A and Margi S (2007). Hematology and hemostasis. In:
Charles MHand Margi S (Eds). Laboratory Procedures
CLINICAL SIGNS OF EXPERIMENTAL TRYPANOSOMA EVANSI INFECTION IN …
for Veterinary Technicians. Fifth edition, Mosby
Elsevier Inc., St Louis Missouri, pp. 27-73.
El Rayah IE, Kaminsky R, Schmid C and El Malik KH
(1999). Drug resistance in Sudanese Trypanosoma
evansi. Vet. Parasit., 80: 281-287.
Enwezor FNC and Sackey AKB (2005). Camel
Trypanosomosis-A Review. Vet. Arhiv., 75: 439-452.
Faye D, Pereira de Almeida PJ, Goossens B, Osaer S, Ndao
M, Berkvens D, Speybroeck N, Nieberding F and Geerts
S (2001). Prevalence and incidence of trypanosomosis in
horses and donkeys in The Gambia. Vet. Parasit., 101(2):
101-114.
FAO (2012). A field guide for the diagnosis, treatment and
prevention of African animal trypanosomiasis. Retrieved
September 22, (2012) from, www.///C:/Users/HPUSER/
Documents/trypanosomeschemotherapy.htm.
FAO (2014). Animal production: Section 1, Modul 5,
Livestocks Systems Research Manual Vol. 1. Produced
by ILRI. Retrieved December 16, (2014) from,
www.fao.org/wairdocs/ilri/x5469e/5469e08.htm.
Gardiner PR and Mahmoud MM (1990). Salivarian
trypanosomes Causing Disease in Livestock Outside
Sub-Saharan Africa In: Baker JR (Ed), Parasitc Protozoa,
vol. 3, pp. 1-68. Acad. Press., New York, NY, USA.
Gutiérrez C, González-Martín M, Corbera JA and TejedorJunco MT (2013). Chemotherapeutic agents against
pathogenic
animal
trypanosomes.
http://www.formatex.info/microbiology4/vol3/15641573.pdf.
Habila N, Inuwa MH, Aimola IA, Udeh MU and Haruna E
(2012). Pathogenic mechanisms of Trypanosoma evansi
infection. Res. Vet. Sci., 93(1): 13-17.
Herrera HM, Davila AM, Norek A, Abru UG, Souza SS,
Andrea PSD and Jansen AM (2004). Enzootiology of
Trypanosoma evansi in the pantanal. Braz. Vet. Parasit.,
125: 263-275.
Hunt R (2010). Microbiology and Immunology: Parasitology.
Univ. S. C., pp. 1-6.
ILRI (International Livestock Research Institute) Monograph
(1997). Disease resistance and protecting the
environment. In; Livest., People Environ., p. 10-11.
Joe A (2012). The Donkey Sanctuary. British Veterinary
Association. Retrieved February 11, (2012) from,
www.bva.co.uk.
Klaus DE (1996). Immunology: Understanding the Immune
System. First edition, Wiley-liss Inc., USA. pp. 1-103.
Mead R, Curnow RN and Hasted AM (2002). Statistical
Methods in Agriculture and Experimental Biology (Texts
in Statistical Science). Third Ed., Chapman and
Hall/CRC, UK. pp. 488.
Mihret A and Mano G (2007). Bovine trypanosomosis in three
districts of East Gojjan zone bordering the blue, Nile
River in Ethiopia. J. Infected Dev. Countries., 1(3): 321325.
Monzon CM, Mancebo OA and Roux JP (1990). Comparison
between 6 parasitological methods for diagnosis of
Trypanosoma evansi in the subtropical area of Argentina.
Vet. Parasit., 36: 141-146.
900
Monzon CM (2006). Characterisation of a monoclonal
antibody against Trypanosoma evansi and its application
for detecting circulating antibodies. Revue Scientifique
ET Tech., 25(3): 1067-1074.
Maudlin I, Holmes PH and Miles MA (2004). The
Trypanosomiasis. CABI Publishing CAB Int.
Oxfordshire., UK. pp. 25-30 and 283-331.
Murray RK, Granner DK, Mayes PA and Rodwell VW
(2003). Harper’s Illustrated Biochemistry a Lange
Medical Book. 26th edition, The McGraw-Hill
Companies, Inc., USA, pp. 622-701.
Mutugi JJ, Young AS, Maritim AC, Ndungu SG, Stagg DA
Grootenhuis JG and Leitch BL (1988). Immunization of
cattle against theileriosis using varying doses of Theileria
parva and Theileria parva lawrencei sporozoites and
oxytetracycline treatments. Int. J. Parasit., 18: 453-461.
OIE [Office International des Epizootes] (2004). Manual of
diagnostic tests and vaccines for terrestrial animals
[online]. Paris: OIE; Trypanosoma evansi infections
(including surra). Retrieved August 27, (2009) from,
http://www.oie.int/eng/normes/mmanual/2008/pdf/2.01.1
7_TRYPANO.pdf.
OIE [Office International des Epizootes] (2010). Trypanosoma
evansi infection (surra).Version adopted by The World
Assembly of Deligates of the OIE in May (2010).
Chapter 2.1.17. Retrieved November 24, (2012) from,
http://www.oie.int/fileadmin/Home/eng/Health_standard
s/tahm/2.01.17_TRYPANO.pdf.
Omer HO, Mousa HM and Al-Wabel N (2007). Study on the
antioxidant status of rats experimentally infected with
Trypanosoma evansi. Vet. Parasit., 145: 142-145.
Rami M, Atarhouch T, Bendahman MN, Azlaf R, Kechna R,
Dakkak A (2003). Camel’s trypanosomasis in Morocco
2: A Pilot Disease Control Trial. Vet. Parasit., 115: 223231.
Rickman WJ and Cox HW (1983). Trypanosome antigen–
antibody complexes and immunoconglutinin interaction
in African trypanosomiasis. Int. J. Parasit., 13: 389-392.
Saleh MA, Al-Salhy BM and Sanousi SA (2009). Oxidative
stress in blood of camels naturally infected with
Trypanosoma evansi. Vet. Parasit., 162: 192-199.
Shapiro TA, Englund PT (1990). Selective cleavage of
kinetoplast
DNA
minicircles
promoted
by
antitrypanosomal drugs. Proceedings Natl Acad. Sci.,
USA. 87: 950-954.
Silva RAMS, Arosemena NAE, Herrera HM, Sahib CA and
Ferreira MSJ (1995). Outbreak of trypanosomosis due to
Trypanosoma evansi in horses of Pantanal Matogrossense, Brazil. Vet. Parasit., 60(1-2): 167-171.
Starkey P (1995). The donkey in South Africa: Myths and
misconceptions. In: Starkey P (Ed). Animal Traction in
South Africa: Enpowering Rural Communities. Halfway
House, Dev. Bank Sout. Afr., pp. 139-151.
Stephen L (1986). Trypanosomiasis: A Veterinary
Perspective. Pergamon Press, New York, USA.
Stewart AJ (2013). Intestinal diseases in horses and foals;
Diarrhoea in horses. Reviewed/revised in September
(2013).
Retrieved
August
24,
(2014) from
J. Vet. Adv., 2015, 5(4): 891-901
GARBA ET AL.
http://www.merckmanuals.com/vet/digestive_system/int
estinal_diseases_in_horses_and_foals/diarrheal_disease_
in_horses.html.
Suswam EA, Taylor DW, Ross CA and Martin RJ (2001).
Changes in properties of adenosine transporters in
Trypanosoma evansi and modes of selection of resistance
to the melaminophenyl arsenical drug, MelCy. Vet.
Parasit., 102: 193-208.
Vittoz R (1955). Prophylaxix of surra in Asia. Bull. OIE., 49:
83-106.
Wayne L and Melvin B (2000). Determining age of horses by
their teeth, Extension and Agricultural Information, 1-98
Agri. Buil., Columbia, MO 65211; XPLOR website:
http://extension.missouri.edu/publications/inde.aspx.
Accessed. 12: 30 GMT July 20, (2011).
Weiser G (2012). Sample collection, processing and analysis
of laboratory service options, In: Mary AT, Glade W,
Robin WA and Terry WC (Eds). Vet. Hematol. Clin.
Chem. Sec. Ed., Wiley-Black Well, UK. pp. 34-50.
Wolfensohn S and Lloyd M (2013). Handbook of Laboratory
Animal Management and Welfare. Fourth edition,
Wiley-Blackwell Publ. Ltd, UK. pp. 371.
Wolkmer P, Da Silva AS, Traesel CK, Paim FC, Cargnelutti
JF, Pagnoncelli M, Picada ME, Monteiro SG, Anjoslopes
ST (2009). Lipids peroxidation associated with anemia in
rats experimentally infected with Trypanosoma evansi.
Vet. Parasit., 165: 41-46.
Woo PTK (1970). The haematocrit centrifugation technique
for the diagnosis of African trypanosomiasis. Acta Trop.,
27(4): 384-386.
Wosu LO (2002). The veterinarian’s handbook. First edition,
Mike Soc. Press., Nsukka, Nigeria. pp. 268.
Zhou J, Shen J, Liao D, Zhou Y and Lin J (2004). Resistance
to drug by different isolates of Trypanosoma evansi in
China. Acta Trop., 90: 271-275.
901
J. Vet. Adv., 2015, 5(4): 891-901