African
Journals Online
Journal of the South African Veterinary Association
Volume 74 Number 1, March 2003
ABSTRACTS
Little anthelmintic drenching required for lambs
finished over winter and spring on annually re-established irrigated
pasture on the Highveld of Gauteng province, South Africa
Van Wyk,
J.A.; Meyer, J.; Van Rensburg, L.J.
Abstract:
As part of a trial to test the profitability of finishing weaner lambs
over winter and spring on the Highveld of Gauteng province, an
investigation was carried out over 4 consecutive years as to whether
or not worm control was necessary while the lambs were on irrigated,
improved pastures. Pastures that had not been grazed by sheep or other
livestock for at least 5 years were planted to annual ryegrass (Lolium
multiflora) that was ploughed under and replanted annually. Weaner
lambs were randomly divided into either 2 (A and B) or 3 (A, B and C)
groups and finished from April / May to November / December on a
separate pasture per group. While Group A lambs were dewormed before
being placed on pasture, those in Groups B and C were not. Faecal egg
counts were performed at irregular intervals, and when the lambs were
sold at the conclusion of each year's trial, the gastrointestinal
tracts of 4-5 lambs per trial group were processed for worm recovery. Haemonchus
contortus was the dominant wormspecies, while Trichostrongylus
colubriformis, Ostertagia circumcincta and Trichuris
spp. were encountered sporadically. From the results obtained it seems
unlikely that there is appreciable 'carry-over' of the various
wormspecies from year to year on pastures that are ploughed and
replanted annually; thus it is improbable that there will be a
build-up of anthelmintic-resistant worms. While on pasture, no
drenching was required for the Group A lambs (dewormed before placing
on the pasture), nor in 2 of the 4 years in Groups B or B+C that were
not drenched and were lightly infected at the start. In the remaining
2 years Groups B or B+C were drenched once only during the course of
each trial. Thus, under the conditions as in this study, little worm
control is necessary, provided faecal worm egg counts are done to
gauge the levels of infection before the lambs are placed on pasture,
and to guard against the possibility of an increase in worm burdens
thereafter in some years. Also, because of the apparent lack of
carry-over between years, anthelmintic treatment at the time of
introduction of the lambs or during the period of finishing should be
safe as regards progressive selection for anthelmintic resistance. It
is also likely to be cost-effective, considering the low cost of
anthelmintics in relation to the price of lambs, to counter the
possibility of a loss in production if lambs were to harbour
relatively heavy worm burdens when introduced.
Toxicokinetics of cotyledoside following
intravenous administration to sheep
Botha, C.J.;
Rundberget, T.; Swan, G.E.; Mulders, M.S.G.; Flaoyen, A.
Abstract:
Cotyledoside, a bufadienolide cardiac glycoside, was administered
intravenously to sheep in 2 studies. In experiment 1, sheep (n
= 4) received 0.0135 mg / kg daily on 5 consecutive days and in the
2nd experiment, sheep (n = 4) received 0.027 mg / kg as a
single dose. Jugular blood was collected at different time intervals
and kinetic parameters were determined. The data fitted a
1-compartmental model. In both experiments a short half-life (t1/2)
and mean residence time (MRT), a relative small volume of distribution
(Vdss) and rapid clearance were calculated. In the 1st
experiment, t1/2 and MRT increased significantly
(P < 0.007) from Day (D) 0 to D 4. It is suggested that the
rapid decline in plasma cotyledoside concentrations in sheep denotes
rapid distribution of cotyledoside to the tissues or extracellular
spaces and possible accumulation at the biophase.
Volume
of the ligamentum capitis femoris in osteoarthritic hip joints
of adult dogs
Mande, J.D.;
Mbithi, P.M.F.; Mbugua, S.W; .Buoro, I.B.J.; Gathumbi, P.K.
Abstract:
Ventrodorsal pelvic radiographs were made of 32 adult dogs under
general anaesthesia. The hip joints were evaluated according to the
severity of osteoarthritic changes graded as 0, 1, 2 or 3. The dogs
were euthanased, the hip joints opened and the ligamentum capitis
femoris dissected out in toto. The volume of each ligament
was determined using a water displacement technique and the mean
volume compared to the four radiographic grades of osteoarthritis.
There was an inverse correlation (r = -0.75) between the mean
volume of the ligamentum capitis femoris and the increasing
severity of osteoarthritis as assessed by radiography. The results
confirmed the crucial role of radiography in the clinical evaluation
of hip dysplasia and osteoarthritis in the adult dog. Assessment of
the volume of the ligamentum capitis femoris revealed that it
is an important tool for research in canine hip dysplasia and
osteoarthritis.
Diseases of free-ranging chickens in the Qwa-Qwa
district of the northeastern Free State province of South Africa
Thekisoe,
M.M.O.; Mbati, P.A.; Bisschop, S.P.R.
Abstract:
A total of 177 free-ranging chickens from 19 Qwa-Qwa villages were
bled from wing veins over a period of 6 months (June-November 2000).
Serological tests indicated that 5 % of chickens tested had been
exposed to Newcastle disease, 43 % to infectious bronchitis and 63 %
to Mycoplasma gallisepticum infection. McMaster and Visser
sieve techniques were used to determine helminth and coccidia from
pooled fresh faecal samples. Helminths isolated in 37 % of the
villages investigated were Heterakis, Ascaridia and Capillaria
species. Eimeria species were also isolated in 32 % of the
villages investigated. The red fowl mite (Dermanyssus gallinae)
was isolated from some of the birds and their nests. Data from a
questionnaire survey indicated that all farmers interviewed had never
received any technical support and that their chickens had never been
vaccinated against any avian diseases. Only 10.5 % of the owners
interviewed had scientific knowledge on poultry diseases. There is an
urgent need for the government to support free-ranging poultry farmers
by providing subsidised vaccinations and technical support in order to
develop and stimulate economic development in impoverished rural areas
of South Africa.
A survey of reproductive success in South African
Thoroughbred horse breeding from 1975 to 1999
Schulman,
M.L.; Marlow, C.H.B.; Nurton, J.P.
Abstract:
The data and an analysis of the statistical summaries from the 'Return
of Mares' of the General Stud Book of The Jockey Club of
Southern Africa from 1975-1999 are presented. The total number of
mares covered per season ranged from 7393 (1992) to 5180 (1995). The
total living produce in the period surveyed was 95 317 foals. The
categories of data examined include: the total number of mares covered
per season; the total numbers and percentage of their living produce;
the total numbers and percentage dead produce, 'slips' and foals born
dead, barren and 'no return' mares; and the total number of live twins
reported. The percentage live foals per season increased from 52 to 62
% and the percentage barren and 'no return' mares declined from 35.50
to 28.40 % over the period surveyed. The number of live twins reported
showed a dramatic reduction from 156 to 5. These apparent improvements
are ascribed to a combination of factors including advances in
veterinary knowledge and technology. The findings are similar to those
reported by similar surveys of national Thoroughbred populations from
North America and Germany. There is an indication to broaden this
annual survey by recording additional parameters more accurately
reflecting reproductive efficiency rather than a cumulative annual
total of live foals.
Histological
evidence of chytridiomycete fungal infection in a free-ranging
amphibian, Afrana fuscigula (Anura: Ranidae), in South Africa:
short communication
Lane, E.P.;
Weldon, C.; Bingham, J.
Abstract:
The 1st recorded histological evidence of chytridiomycete fungal
infection in a free-ranging ranid amphibian in South Africa is
presented. Literature on causes of a worldwide decline in amphibian
populations is briefly reviewed.
A
note on endoparasites of wild ostriches (Struthio camelus) in
the Mokolodi Nature Reserve, Gaborone, Botswana: short communication
Mushi, E.Z.;
Binta, M.G.; Chabo, R.G.; Toto, P.A.S.
Abstract:
A study was undertaken to investigate the prevalence of endoparasites
of wild ostriches at Mokolodi Nature Reserve, Gaborone, over a 7-month
period. Large numbers of strongyle eggs were recovered from faecal
material in April and September and a decline in the strongyle egg
counts was evident during June and July. Noteworthy was the absence of
helminth eggs in faecal samples collected from chicks and coccidia
oocysts from any of the ostriches.
Seasonal
fluctuation of parasitic infestation in donkeys (Equus asinus)
in Oodi village, Kgatleng District, Botswana: short communication
Mushi, E.Z.;
Binta, M.G.; Chabo, R.G.; Monnafela, L.
Abstract:
During the period March to September 2000, a study was conducted in
Oodi village, Kgatleng District, Botswana, to investigate the seasonal
fluctuation of internal, external and blood parasites of donkeys.
Twelve adult donkeys were randomly selected from a farmer with a herd
of 15 donkeys. Monthly visits were made to the farmer when the donkeys
were examined for parasites. The only ectoparasites recovered from the
donkeys were instars of various tick species. The most prevalent tick
was Rhipicephalus evertsi evertsi (98.4 %), followed by Amblyomma
hebraeum and Hyalomma species. The only haemoparasite seen
on microscopy was Babesia equi at low parasitaemia in 26.8% of
the donkeys. However, no clinical babesiosis was evident. Coprological
examination showed the presence of strongyle eggs in moderate numbers.
Very low numbers of coccidia oocysts were found in the faecal samples.
High tick numbers and worm egg counts coincided with the warm, wet
months in contrast to the low numbers recovered during the cold, dry
months. An interview conducted by the authors indicated that donkeys
were nutritionally marginalised by owners. Supplementary feeding was
therefore recommended, especially during the winter months when
grazing is poor.
Vine
snake (Thelotornis capensis) bite in a dog: clinical
communication
Otto, J.;
Blaylock, R.
Abstract:
A vine snake bite in a dog is reported. There was continued minor
bleeding from the assumed nose bite site for 4 days. Currently
manufactured snakebite antivenom is not effective against vine snake
bites and treatment is supportive.
Tumoral calcinosis in a dog with chronic renal
failure: clinical communication
Spotswood,
T.C.
Abstract:
A 2-year-old male German shepherd dog in poor bodily condition was
evaluated for thoracic limb lameness due to a large, firm mass medial
to the left cranial scapula. Radiography revealed several large
cauliflower-like mineralized masses in the craniomedial left scapula
musculature, pectoral region and bilaterally in the biceps tendon
sheaths. Urinalysis, haematology and serum biochemistry showed that
the dog was severely anaemic, hyperphosphataemic and in chronic renal
failure. The dog was euthanased and a full post mortem performed. A
diagnosis of chronic renal failure with secondary hyperparathyroidism
was confirmed. The mineralized masses were grossly and
histopathologically consistent with a diagnosis of tumoral calcinosis.
Tumoral calcinosis associated with chronic renal failure that does not
involve the foot pads is rarely seen.
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