Published Projects
Published Projects supported Financially by the Foundation
Ganswindt A, Muenscher S, Henley M, Henley, S, Heistermann M, Palme R, Thompson P, Bertschinger, H Endocrine correlates of musth and the impact of ecological and social factors in free-ranging African elephants (Loxodonta africana), Hormones and Behavior (2010), doi: 10.1016/j.yhbeh.2010.02.009
Department of Production Animal Studies, Faculty of Veterinary Science,
University of Pretoria, Private Bag X04, Onderstepoort 0110, South Africa
aganswindt@zoology.up.ac.za
Abstract
Sexual activity in mature male African elephants is predominantly associated with the
occurrence of musth, a state or condition which refers to a set of physical, physiological
and behavioral characteristics, including an elevation in androgen levels. Although musth
appears to be energetically costly, the degree to which it is associated with changes in
adrenal endocrine function (e.g., glucocorticoid output) is still unclear. To investigate the
possible effect of musth on adrenocortical function, and the impact of socioecological
changes on androgen and glucocorticoid levels, six adult African elephant bulls were
followed for 13 months in the Kruger National Park, South Africa, and observations and
fecal sample collection for endocrine monitoring was carried out about twice weekly. Our
data showed that the occurrence of musth was associated with reduced glucocorticoid
output, suggesting that musth does not represent a physiological stress mediated by the
hypothalamic-pituitary-adrenal axis. This confirms previous findings in captive-housed
animals, providing evidence for a suppressive effect of the musth condition on
adrenocortical activity. Furthermore, a seasonal effect on androgen and glucocorticoid
levels was found, which appears to vary depending on the reproductive status of the
animal. The results also indicate a relationship between the presence or absence of social
partners and changes in testicular and adrenal endocrine activity. Finally, the data confirm
previous findings in captive-housed elephants, that an elevation in androgen
concentrations usually occurs before the onset of physical musth signs, and therefore
support the idea that the change in androgen levels represents the initial stimulus for the
musth condition.
Dzikiti TB, Stegmann GF, Hellebrekers LJ, Auer RE, Dzikiti LN. Sedative and cardiopulmonary effects of acepromazine, midazolam, butorphanol, acepromazine-butorphanol and midazolam-butorphanol on propofol anaesthesia in goats. J S Afr Vet Assoc. 2009;80(1):10-16
Anaesthesiology Section, Companion Animal Clinical Studies Department, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, 0110 South Africa.
brighton.dzikiti@up.ac.za
Abstract
The sedative, propofol-sparing and cardiopulmonary effects of acepromazine, midazolam, butorphanol and combinations of butorphanol with acepromazine or midazolam in goats were evaluated. Six healthy Boer - Indigenous African crossbreed goats were by randomised cross-over designated to 6 groups: Group SAL that received saline, Group ACE that received acepromazine, Group MID that received midazolam, Group BUT that received butorphanol, Group ACEBUT that received acepromazine and butorphanol and Group MIDBUT that received midazolam and butorphanol as premedication agents intramuscularly on different occasions at least 3 weeks apart. The degree of sedation was assessed 20 minutes after administration of the premedication agents. Thirty minutes after premedication, the dose of propofol required for induction of anaesthesia adequate to allow placement of an endotracheal tube was determined. Cardiovascular, respiratory and arterial blood-gas parameters were assessed up to 30 minutes after induction of general anaesthesia. Acepromazine and midazolam produced significant sedation when administered alone, but premedication regimens incorporating butorphanol produced inconsistent results. The dose of propofol required for induction of anaesthesia was significantly reduced in goats that received midazolam alone, or midazolam combined with either acepromazine or butorphanol. The quality of induction of anaesthesia was good in all groups, including the control group. Cardiovascular, respiratory and blood-gas parameters were within normal limits in all groups and not significantly different between or within all groups. In conclusion: sedation with midazolam alone, or midazolam combined with either acepromazine or butorphanol significantly reduces the induction dose of propofol with minimal cardiopulmonary effects in goats.
Pretorius JA, Oosthuizen MC, van Vuuren M. Gammaherpesvirus carrier status of black wildebeest (Connochaetes gnou) in South Africa. J S Afr Vet Assoc. 2008;79(3):136-41.
Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort 0110, South Africa.
jana@thabamanzi.co.za
Abstract
Malignant catarrhal fever (MCF) is an economically important disease primarily of domestic cattle with a high case fatality rate. It is caused by either alcelaphine herpesvirus type 1 (AlHV-1) or ovine herpesvirus type 2 (OvHV-2). The major reservoir host of AlHV-1 is the blue wildebeest (Connochaetes taurinus), but it is generally accepted that the black wildebeest (Connochaetes gnou) is also a reservoir host. No viral studies in the black wildebeest have been reported and the carrier status of black wildebeest has not been documented. Specimens were collected from several game farms and conservation areas in central South Africa representing the geographical area historically linked to the natural habitat of the black wildebeest. Specimens were obtained from 304 black wildebeest of different ages and sex, as well as 51 black wildebeest foetuses at different stages of gestation. Virus was isolated from a black wildebeest calf. Morphological features and antigenic characteristics suggested it to be a gammaherpesvirus closely related to AlHV-1. All serum samples tested positive with a competitive inhibition enzyme-linked immunosorbent assay (CI-ELISA) for group-specific malignant catarrhal fever virus antibody. A SYBR Green real-time PCR assay was developed for the detection of gammaherpesviral DNA. Only 15.8 % of the animals tested positive with the real-time PCR assay whereas 90 % of the foetuses tested positive. This finding suggests that, unlike OvHV-2 infection in lambs in which the infection takes place after weaning, the virus in black wildebeest is mainly transmitted in utero or soon after birth. The results suggest that black wildebeest are latent carriers of a gammaherpesvirus similar or closely related to AlHV-1 present in blue wildebeest and that it is likely that all black wildebeest are persistently infected.
Schoeman J P, Herrtage ME. The
response of the pituitary-adrenal and pituitary-thyroidal axes to the plasma
glucose perturbations in Babesia canis rossi babesiosis. J
S Afr Vet Assoc. 2007;78(4):215-220.
Department of Companion Animal Clinical Studies, Faculty of Veterinary
Science, University of Pretoria, Onderstepoort, 0110 South Africa.
johanp.schoeman@up.ac.za
Abstract
This prospective, cross-sectional, interventional study was designed to
determine the association between the hormones of the pituitary-adrenal and
pituitary-thyroid axes and other clinical parameters with the blood glucose
perturbations in dogs with naturally occurring Babesia canis rossi
babesiosis. Thirty-six dogs with canine babesiosis were studied. Blood
samples were obtained from the jugular vein in each dog prior to treatment
at admission to hospital and serum endogenous adrenocorticotrophic
hormone(ACTH), pre-ACTH cortisol, thyroxine, free thyroxine and TSH
concentrations were measured. Immediately thereafter each dog was injected
intravenously with 5 µg/kg of ACTH (tetracosactrin). A 2nd blood sample was
taken 1 hour later for serumpost-ACTHcortisol measurement. Three patient
groups were recruited: hypoglycaemic dogs (glucose < 3.3 mmol/â„“, n = 12);
normoglycaemic dogs (glucose 3.3�5.5 mmol/ℓ, n = 12); hyperglycaemic
dogs (glucose > 5.5 mmol/â„“, n = 12). Basal and post-ACTH serum cortisol
concentrations were significantly higher in hypoglycaemic dogs, whereas body
temperature, serum thyroxine and free thyroxine were significantly lower in
hypoglycaemic dogs. Haematocrit was significantly lower in both hypo-and
hyperglycaemic dogs compared with normoglycaemic dogs. Low blood glucose
concentrations were significantly associated with high basal and post-ACTH
cortisol concentrations and with low serum thyroxine and free thyroxine
concentrations in dogs suffering from B. canis rossi babesiosis.
Köster LS, Schoeman JP, MeltzerDGA. ACTH
stimulation test in the captive cheetah (Acinonyx jubatus). J S Afr Vet
Assoc. 2007;78(3):133-136.
Veterinary Wildlife Unit, Faculty of Veterinary Science, University of
Pretoria, Private Bag X04, Onderstepoort, 0110 South Africa
Abstract
Serum cortisol response was assessed in 8 captive cheetahs, of varying ages,
after the intravenous administration of 500 μg of tetracosactide (Synacthen
Depot®, Novartis, Kempton Park) while maintained under general anaesthesia.
In addition, 8 cheetahs were anaesthetised and given an equal volume of
saline in order to establish baseline cortisol concentrations at similar
stages of anaesthesia. A significant difference in the median cortisol
concentration measured over time was found following ACTH administration in
the ACTH group (P<0.001). There is no difference between the median cortisol
concentrations in the ACTH group at time-points 120, 150 and 180 min after
ACTH stimulation (P=0.867). Thus it appears appropriate to collect serum 120
to 180 min after tetracosactide administration to assess maximal stimulation
of the adrenal in the cheetah. No statistically significant rise was seen in
the anaesthetised control group following the injection of saline (P =
0.238).
Lovely CJ, Pittman JM, Leslie, AJ. Normal
haematology and blood biochemistry of wild Nile crocodiles (Crocodylus
niloticus) in the Okavango Delta, Botswana. J S Afr Vet Assoc.
2007;78(3):137-144.
Gobabis Veterinary Practice, PO Box 1424, Gobabis, Namibia
Abstract
Wild Nile crocodiles (Crocodylus niloticus) of various size classes were
captured in the Okavango Delta, Botswana. Blood was collected from the post
occipital sinus and used for the determination of a wide range of
haematological and biochemical parameters. These values were compared
between the sexes and between 3 size classes. The values were also compared
with the limited data available from farmed Nile crocodiles, as well as from
other wild Nile crocodiles. The Okavango crocodiles were comparatively
anaemic, and had comparatively low total protein and blood glucose levels.
There was a high prevalence of Hepatozoon pettiti infection, however, there
was no significant difference in haematological values between the infected
and uninfected crocodiles. The values reported here will be useful in
diagnostic investigations in both zoo and farmed Nile crocodiles.
Steenkamp G, Ferreira SM, Bester MN. Tusklessness and tusk
fractures in free-ranging African savanna elephants (Loxodonta africana). J
S Afr Vet Assoc. 2007;78(2):75-80.
Mammal Research Institute, University of Pretoria, Pretoria, 0002 South
Africa.
Abstract
The incidence of tusklessness varies between free-ranging African elephant
populations. Sex-linked genetic drift predicts 2 outcomes – the condition
becomes fixed and sex-specific incidences diverge when populations are small
and/or heavily poached. By contrast, for large and intact populations,
tusklessness diminishes and there is no variation between sexes. We tested
these predictions by comparing sex-specific incidences between 15
populations: a small one with a skewed founder effect towards tusklessness;
5 that had experienced intense levels of poaching; 2 that had been subjected
to non-selective culling and 7 that are relatively pristine. Patterns of
rainfall were studied of tusk fractures amongst these populations to correct
for any effect that acquired tusklessness may have on our predictions. The
incidence of tusk fractures was related to annual rainfall, but the
mechanism that leads to an increase of the condition in drier areas was not
clear. Incidences of tusk fractures in free-ranging populations implied that
the frequency of acquired bilateral tusklessness is low and should not
affect our results. All males had tusks. Tusklessness in females was high in
the small skewed founder population and some of those where there was a
history of poaching. The incidence is expected to decline if the residual
population is large.
Koeppel KN, BertschingerH, van Vuuren M, Picard J, Steiner
J, Williams D, Cardwell J. The use of a probiotic in captive cheetahs
(Acinonyx jubatus). J S Afr Vet Assoc. 2006;77(3):127-130 .
Department of Veterinary Tropical Diseases, Faculty of Veterinary
Science, University of Pretoria, Private Bag X04, Onderstepoort, 0110 South
Africa.
Abstract
Juvenile captive cheetahs (Acinonyx jubatus) often present with diarrhoea
that is commonly associated with bacterial infections. A species-specific
probiotic containing Lactobacillus Group 2 and Enterococcus faecium was
prepared from healthy adult cheetahs. Juvenile cheetahs (n = 27) between 8
and 13 months of age were included in the probiotic trial. The animals were
observed prior to and after feeding of the probiotic which was made
available for 28 days. Feeding of the probiotic resulted in a significantly
increased body weight in the treatment group (P = 0.026), while there was no
increase in the control group. A relative improvement in the faecal quality
in the probiotic group during the treatment period compared with the
pre-treatment (P = 0.0363) and post-treatment (P = 0.004) period was
observed. This was accompanied by an absence of blood and mucus in the
faeces during the treatment period in the probiotic group.
Dowdle SM, Joubert KE, Lambrechts NE, Lobetti RG, Pardini AD.The
prevalence of subclinical gastroduodenal ulceration in Dachshunds with
intervertebral disc prolapse. J S Afr Vet Assoc. 2003 Sep;74(3):77-81.
Department of Companion Animal Clinical Studies, Faculty of Veterinary
Science, University of Pretoria, Private Bag X04, Onderstepoort 0110, South
Africa. sdowdle@mweb.co.za
Abstract
Endoscopy was used to determine the prevalence of subclinical gastroduodenal
ulceration in 30 Dachshunds undergoing decompressive surgery for acute
intervertebral disc prolapse. The endoscopy was performed on the day of
admission and on the 3rd or 4th day after surgery. Three regions of the
stomach (cardia, corpus and pylorus) and the proximal duodenum were visually
inspected and biopsy samples were taken for histopathology. The combination
of visual and microscopic changes were then used to determine the prevalence
of subclinical gastroduodenal ulceration in this population. An overall
prevalence of 76% was calculated from these findings. Ulcerogenic medication
administered prior to admission did not appear to influence the prevalence.
This result identifies a need for veterinarians to be aware of this
potentially severe complication and warrants the use of prophylactic
anti-ulcer medication in spinal surgery patients.
Van Niekerk LJ, Verstraete FJ, Odendaal JS. A comparison of the
surgical caseloads of selected companion animal hospitals and a veterinary
academic hospital in South Africa.J S Afr Vet Assoc 2002 Sep;73(3):115-8
Fourways Veterinary Hospital, Johannesburg, PO Box 68159, Bryanston 2021,
South Africa.
Abstract
Educational institutions should be aware of the frequency of surgical
procedures in private practice, to assist both the student and the lecturer
in evaluating the relative importance of procedures and to structure
training programmes accordingly. The surgical caseload for 1 year at a
veterinary academic hospital and 13 private companion animal hospitals
registered with the South African Veterinary Council were compared. Surgical
records were entered into a spreadsheet and sorted according to 96 selected
surgical procedures to facilitate comparisons. Surgical procedures were in
turn grouped according to date, species, degree of difficulty and frequency
of occurrence. Feline procedures were more commonly performed in private
hospitals. The academic hospital's caseload was dominated by major and
advanced procedures while the private hospitals carried out more minor
procedures. At the private hospitals more general surgery, and ear, nose and
throat surgery as well as dental procedures were performed, while at the
academic hospital more ophthalmic, orthopaedic, thoracic and neurosurgical
procedures were carried out. The most commonly performed procedures at the
academic hospital differed from those at the private hospitals. No seasonal
trends were evident.
Quan M, Mulders MS, Meltzer DG.The effect of storage
conditions on samples for the evaluation of copper status in
blesbok (Damaliscus pygargus phillipsi).J S Afr Vet Assoc 2002
Sep;73(3):111-4
Wildlife Unit, Faculty of Veterinary Science, University of Pretoria,
Private Bag X04, Onderstepoort 0110, South Africa.
Investigations to determine the effect of sample storage on the
concentration of copper in liver tissue and on the activity of
erythrocyte superoxide dismutase were undertaken in preparation
for a study of blesbok (Damaliscus pygargus phillipsi) that were
suspected to be suffering from copper deficiency. Two liver
samples were collected from each of 20 culled blesbok in a
manner that simulated the collection of biopsies from the live
animal. These samples were stored either in 10% formalin or
frozen at -20 degrees C until analysed 4 1/2 months later. The
effect of different methods of sample storage on superoxide
dismutase activity was determined. Erythrocytes collected from 3
Jersey cows and 5 culled blesbok were washed and divided into
0.5 ml portions, stored at room temperature (approximately 20
degrees C), in a refrigerator (4 degrees C), frozen at -20
degrees C in a freezer, and in liquid nitrogen (-200 degrees C).
An analysis of superoxide dismutase activity was undertaken
using a commercial assay kit at intervals of 2-4 days until the
levels of activity had fallen significantly. The copper
concentration in formalin-preserved liver samples was
significantly lower than that measured in frozen liver tissue
apparently as a result of leaching. The activity of superoxide
dismutase in cattle blood was unchanged for 4 days at room
temperature but fell appreciably after 2 days at 4 degrees C and
-20 degrees C. Enzyme activity remained unchanged for 200 days
in erythrocytes stored in liquid nitrogen. Superoxide dismutase
activity levels in healthy blesbok were considerably lower than
those measured in Jersey cows and remained unaffected for up to
6 days in samples stored at 4 degrees C and 20 degrees C. The
level of activity fell significantly thereafter. Samples stored
in liquid nitrogen were unchanged after 40 days.
Botha CJ, Naude TW.
Plant poisonings and mycotoxicoses of importance in horses
in Southern Africa.J S Afr Vet Assoc 2002 Sep;73(3):91-7
Department of Paradinical Sciences, Faculty of Veterinary Science,
University of Pretoria, Private Bag X04, Onderstepoort 0110, South Africa.
cbotha@op.up.ac.za
Abstract
Well-known plant poisonings such as 'dunsiekte' (seneciosis) and
'jaagsiekte' (crotalariosis) of horses in southern Africa are briefly
reviewed. Relatively unfamiliar mycotoxicoses such as stachybotryotoxicosis
and perennial rye grass staggers and potentially occurring exotic
intoxications such as equine nigropallidal encephalomalacia and ergot
alkaloid poisoning are also discussed. This article is aimed at informing
the southern African equine practitioner about probable poisonings that
might occur locally in horses.
Schoeman T, Lobetti RG, Jacobson LS, Penzhorn BL. Feline
babesiosis: signalment, clinical pathology, and concurrent infections.
Journal of the South African Veterinary Association 2001 72:4-11.
Department of Companion Animal Medicine, Faculty of Veterinary Science,
University of Pretoria, Onderstepoort, South Africa.
Abstract
Fifty-six cats with naturally occurring Babesia felis infection were
studied. No breed or sex predilection could be identified, but there was an
apparent predilection for young adult cats less than 3 years of age.
Macrocytic, hypochromic, regenerative anaemia was present in 57 % of the
cats and in-saline agglutination tests were positive in 16 %. No
characteristic changes were observed in total or differential leukocyte
counts. Thrombocyte counts were variable and thrombocytopaenia was an
inconsistent finding. Hepatic cytosol enzyme activity and total bilirubin
concentrations were elevated in the majority of cats. Serum protein values
were mostly normal, but increased values were occasionally observed and
polyclonal gammopathies were observed in all cats with increased total
globulin concentrations. No remarkable changes in renal parameters were
observed. A variety of electrolyte abnormalities occurred in a number of
cats, but no consistent pattern of change could be identified. A close
correlation was evident between peripheral and central parasite counts.
Concurrent infections with Haemobartonella felis, feline immunodeficiency
virus and/or feline leukemia virus were identified in a number of cats.
Lobetti RG, Jacobson LS. Renal involvement in dogs with
babesiosis. Journal of the South African Veterinary Association 2001
72:23-28.
Department of Companion Animal Medicine, Faculty of Veterinary Science,
University of Pretoria, Onderstepoort, South Africa.
Abstract
Proteinuria, and renal tubular casts and epithelial cells in urine sediment,
are commonly observed in both complicated and uncomplicated babesiosis, but
do not necessarily reflect or predict renal failure. This study investigated
the presence and degree of renal damage in canine babesiosis. Renal function
and integrity were evaluated using scrum urea and creatinine, serum
electrolytes (sodium and potassium), fractional clearance of sodium (Fc
Na)
and potassium (Fc
K), urine enzyme activity of gamma-glutamyl
transpeptidase and alkaline phosphatase, urine protein:creatinine ratio, and
urinalysis. One control group (n = 10) and 3 groups of babesiosis cases were
studied: mild uncomplicated (n = 10), severe uncomplicated (n = 11), and
complicated (n = 9). All babesiosis groups showed well concentrated urine.
Mean serum urea was elevated in the severe and complicated groups, and was
significantly different from the control group. There was no statistically
significant difference between the groups for creatinine, although the
complicated group had a mean value above the normal reference range.
Hypokalaemia was uncommon in all the groups. Hyperkalaemia was present in
only 2 dogs in the complicated group. Marginal hyponatraemia was present in
a minority of dogs in all groups. The serum electrolytes were not
significantly different between groups. There was no overall elevation, nor
any statistically significant difference in both the Fc
Na and Fc
K
between the groups. Only 1 dog, in the complicated group, showed marked
enzymuria. Proteinuria was a common finding and was significantly different
between the severe and complicated groups and the control group. Some dogs
in all groups had renal tubular epithelial cells in the urinary sediment,
which increased in severity from the mild to the complicated groups and was
significantly different from the control group. This study demonstrated that
minimal renal damage occurs more often in canine babesiosis than significant
damage or acute renal failure.
Lobetti RG, Mohr AJ, Dippenaar T, Myburgh E. A
preliminary study on the serum protein response in canine babesiosis.
Journal of the South African Veterinary Association 2000 71:38-42.
Department of Companion Animal Medicine, Faculty of Veterinary Science,
University of Pretoria, Onderstepoort, South Africa.
Abstract
Total serum protein, albumin, globulin, globulin fractions (alpha, beta and
gamma globulins) and an acute-phase protein (alpha1-acid glycoprotein) were
evaluated in dogs with naturally occurring mild (Group 1), severe (Group 2)
or complicated babesiosis (Group 3). Results showed that the total serum
protein, albumin, A/G ratio and alpha globulins were statistically different
between Groups 1 and 2. There was no statistical difference between groups
with total, beta and gamma globulins. The findings from this study suggest
that dogs with mild and severe babesiosis had low total serum proteins,
albumin, A/G ratio and alpha globulins; dogs with complicated babesiosis
showed no typical serum protein changes or patterns; and that there was no
evidence of an acute-phase response detectable on serum protein
electrophoresis in any of the 3 groups. A marked acute-phase response was,
however, present, as measured by the alpha1-acid glycoprotein, in all 3
groups. As this was a retrospective study, the possibility that the observed
responses were due in part to concurrent disease could not be excluded
Matthee S, Krecek RC, Milne SA. Prevalence and
biodiversity of helminth parasites in donkeys from South Africa. Journal of
Parasitology 2000 86:756-62.
Department of Veterinary Tropical Diseases, Faculty of Veterinary Science,
University of Pretoria, Onderstepoort, South Africa.
Abstract
Seven donkeys (Equus asinus) from North-West and Mpumalanga Provinces in
South Africa were examined at necropsy. Quantitative samples were collected
from the gastrointestinal tract for recovery of helminth parasites from the
stomach, small intestine, cecum, ventral colon, dorsal colon, descending
colon, and cranial mesenteric artery. Fifteen genera and 29 species of
helminths were identified comprising 27 species of nematodes in the
Ascarididae, Atractidae, Habronematidae, Onchocercidae, Oxyuridae, and
Strongylidae; 1 species of cestode in the Anoplocephalidae; and 1 species of
trematode in the Paramphistomatidae. In addition, 2 species of oestrid fly
larvae in the Gastrophiliidae were identified. The most abundant group in
number of species was the cyathostomes (small strongyles) and, of these,
Cyathostomum montgomeryi, Cylicocyclus sp. (a), and Cylicostephanus minutus
were the most numerous. The most prevalent cyathostomes were C. montgomeryi
and Cylicocyclus sp. n. (a). Strongylus vulgaris was the most abundant and
prevalent large strongyle species. The occurrence of small strongyle species
and their prevalence in this study are compared with 3 other studies on
donkeys in Africa.
Jacobson LS, Lobetti RG, Vaughan-Scott T. Blood
pressure changes in dogs with babesiosis.
Journal of the South African Veterinary Association 2000 71:38-42.
Department of Companion Animal Medicine, Faculty of Veterinary Science,
University of Pretoria, Onderstepoort, South Africa.
Abstract
Systemic arterial blood pressures were measured in 30 dogs with acute
babesiosis, 10 each with mild uncomplicated, severe uncomplicated and
complicated disease. Ten healthy dogs were used as controls. Hypotension was
defined as more than 3 standard deviations below the control mean. Normal
mean pressures (+/-SD) were: systolic arterial pressure 151 (+/-11) mm Hg,
diastolic arterial pressure 89 (+/-8) mm Hg and mean arterial pressure 107
(+/-10) mm Hg. Hypotension was the most frequent abnormality, and increased
strikingly in incidence as disease severity increased, with 5/10 dogs in the
complicated group being hypotensive for systolic, diastolic and mean
arterial pressures, compared with 2/10 in the severe uncomplicated group and
0/10 in the mild uncomplicated group. Systolic, diastolic and mean arterial
pressures in the complicated group and severe uncomplicated group, and
systolic pressure in the mild uncomplicated group, were significantly lower
than in the controls. There were no significant relationships between
arterial pressures and age, pulse rate, respiratory rate, temperature,
mucous membrane colour or haematocrit. There was a significant negative
correlation between arterial pressures and white cell and immature
neutrophil counts. Arterial pressures differed significantly between dogs
that were clinically collapsed and those that were not, but not between
survivors and non-survivors. Pulse pressure (systolic-diastolic) was low in
7/10 complicated, 1/10 mild uncomplicated, and 1/10 severe uncomplicated
cases, and differed significantly between the complicated and control
groups. The high incidence of hypotension in clinically severe babesiosis
has important implications for therapy.