• A comparative histological study of the number and size of the myenteric ganglia and neurones in the fore-stomach and abomasum of grey, white and black Karakul lambs 

  Groenewald, Hermanus B.; Booth, Kenneth Kurt; Verwoerd, Daniel Wynand (Published by the Agricultural Research Council, Onderstepoort Veterinary Institute., 1992)

  Homozygous grey Karakul lambs are born with a lethal genetic factor responsible for death at weaning age. When put in a high roughage diet under field conditions they develop distended, thin-walled rumens and sand impacted ...
• Description of Aegyptianella botuliformis n. sp. (Rickettsiales: Anaplasmataceae) from the helmeted guineafowl, Numida meleagris 

  Huchzermeyer, Fritz W.; Horak, Ivan Gerard; Putterill, John Fraser; Earle, R.A.; Verwoerd, Daniel Wynand (Pretoria : Agricultural Research Council, Onderstepoort Veterinary Institute., 1992)

  Aegyptianella botuliformis n. sp. (Rickettsiales: Anaplasmataceae) isolated from helmeted guineafowls Numida meleagris from the Kruger National Park is described. The rickettsia occurs within a membrane-bound vacuole in ...
• Adult Amblyomma hebraeum burdens and heartwater endemic stability in cattle 

  Du Plessis, J.L.; Loock, P.J.; Ludemann, C.J.F.; Verwoerd, Daniel Wynand (Published by the Agricultural Research Council, Onderstepoort Veterinary Institute., 1992)

  Several conclusions of importance to studies on the epidemiology of heartwater were drawn from an investigation in which the numbers of adult Amblyomma hebraeum ticks, to which a closed herd of Hereford cattle were exposed ...
• The effects of salt loading via two different routes on feed intake, body water turnover rate and on electrolyte excretion in sheep 

  Meintjes, R.A.; Olivier, Roelina; Verwoerd, Daniel Wynand (Published by the Agricultural Research Council, Onderstepoort Veterinary Institute., 1992)

  The effect of dosing identical amounts of sodium chloride, via 2 different routes, on feed intake and water and electrolyte balance was investigated in sheep. Feed intake and plasma sodium concentrations were unaffected ...
• Serological differentiation of five bluetongue virus serotypes in indirect ELISA 

  Du Plessis, D.H.; Verwoerd, Daniel Wynand (Published by the Agricultural Research Council, Onderstepoort Veterinary Institute., 1992)

  The serological reactivity in indirect ELISA of five different bluetongue virus (BTV) serotypes (4, 10, 15, 16 & 20) was compared using polyclonal antisera raised against virus particles and an outer structural protein, ...
• Cardiotoxicity of the skin of the red-banded rubber frog, Phrynomerus bifasciatus (Smith 1847) 

  Van der Walt, M.P.K.; Van Rooyen, J.M.; Oberholzer, G.; Van Aswegen, G.; Verwoerd, Daniel Wynand (Published by the Agricultural Research Council, Onderstepoort Veterinary Institute., 1992)

  The skin of the red-banded rubber frog is said to secrete an unidentified toxin. Whole skin extract as well as HPLC fractions were tested for toxicity on viable, isolated cardiomyocytes. The skin extract and one of its ...
• A host-parasite catalogue of the haematozoa of the sub-Saharan birds 

  Huchzermeyer, Fritz W.; Bennett, G.F.; Earle, R.A.; Du Toit, Hester; Verwoerd, Daniel Wynand (Published by the Agricultural Research Council, Onderstepoort Veterinary Institute., 1992)

  The prevalence of avian haematozoa in 826 species of birds representing 73 families of sub-Saharan birds as recorded in the literature or in the files of the International Reference Centre for Avian Haematozoa and the ...
• Experimental Albizia versicolor poisoning in sheep and its successful treatment with pyridoxine hydrochloride 

  Gummow, Bruce; Bastianello, Stella S.; Labuschagne, Leonie; Erasmus, G.L.; Verwoerd, Daniel Wynand (Published by the Agricultural Research Council, Onderstepoort Veterinary Institute., 1992)

  Five sheep developed severe nervous signs after being drenched with Albizia versicolor podmaterial. Four of these sheep were treated with pyridoxine hydrochloride (a vitamin B₆) when the symptoms of toxicity became ...
• Flow cytometric analysis of the T cell response in mice infected with Cowdria ruminantium 

  Du Plessis, J.L.; Gray, C.; Van Strijp, M.F.; Verwoerd, Daniel Wynand (Published by the Agricultural Research Council, Onderstepoort Veterinary Institute., 1992)

  A 3-fold increase in the numbers of Lyt-2⁺ T cells in the circulating blood of mice infected and reinfected with the Welgevonden stock of Cowdria ruminantium, as determined by flow cytometry, is supportive evidence that ...
• Incidence of Feline lmmunodeficiency virus reactive antibodies in free-ranging lions of the Kruger National Park and the Etosha National Park in southern Africa detected by recombinant FIV p24 antigen 

  Spencer, J.A.; Van Dijk, A.A.; Horzinek, Marian C.; Egberink, H.F.; Bengis, Roy G.; Keet, D.F.; Morikawa, S.; Bishop, D.H.L.; Verwoerd, Daniel Wynand (Published by the Agricultural Research Council, Onderstepoort Veterinary Institute., 1992)

  Lion sera from the Kruger National Park (KNP) dating back to 1977 and from the Etosha National Park (ENP), obtained from 1989 to 1991 , have been analysed by ELISA and Western blot analyses using a genetically engineered ...
• The louse fly Lipoptena paradoxa Newstead, 1907 (Diptera: Hippoboscidae) : description of its adult and puparium and biology in South Africa 

  Horak, Ivan Gerard; Boomker, Jacob Diederik Frederik; Visagie, Elize J.; Verwoerd, Daniel Wynand (Published by the Agricultural Research Council, Onderstepoort Veterinary Institute., 1992)

  Lipoptena paradoxa Newstead, 1907 is re-described using scanning electron microscopy and its puparium is described for the first time. The distribution of the fly is restricted to the eastern half of South Africa, generally ...
• A new species of Lipoptena (Diptera: Hippoboscidae) from southern Africa 

  Visagie, Elize J.; Verwoerd, Daniel Wynand (Published by the Agricultural Research Council, Onderstepoort Veterinary Institute., 1992)

  A new species of Lipoptena Nitzsch, 1818 was found on springbok Antidorcas marsupialis Zimmerman, 1780 in the Cape Province and the Orange Free State, South Africa. The flies, for which the name Lipoptena annalizeae is ...
• The effect of veld-burning on the seasonal abundance of free-living ixodid ticks as determined by drag-sampling 

  Horak, Ivan Gerard; Braack, L.E.O.; Spickett, Arthur M.; Van Niekerk, Andrea; Verwoerd, Daniel Wynand (Pretoria : Agricultural Research Council, Onderstepoort Veterinary Institute., 1992)

  A supervised veld-burn in the Sclerocarya caffra/Acacia nigrescens Savanna landscape zone in the south-eastern region of the Kruger National Park was carried out during September 1988. The effect of the fire on the free-living ...
• Parasites of domestic and wild animals in South Africa. XXXI. Adult ixodid ticks on sheep in the Cape Province and in the Orange Free State 

  Horak, Ivan Gerard; Fourie, L.J.; Verwoerd, Daniel Wynand (Published by the Agricultural Research Council, Onderstepoort Veterinary Institute., 1992)

  Four to 10 Dorper sheep on each of 12 farms in the Cape Province and 3 farms in the Orange Free State were examined for adult ixodid ticks at approximately 2- to 4-weekly intervals over periods varying from 4 to 18 months, ...
• Parasites of domestic and wild animals in South Africa. XXX. Ectoparasites of kudus in the eastern Transvaal Lowveld and the eastern Cape Province 

  Horak, Ivan Gerard; Boomker, Jacob Diederik Frederik; Spickett, Arthur M.; De Vos, Valerius; Verwoerd, Daniel Wynand (Published by the Agricultural Research Council, Onderstepoort Veterinary Institute., 1992)

  Sets of four kudus were shot and examined for arthropod parasites at approximately monthly intervals from April 1981 to March 1983 in the southern part of the Kruger National Park, eastern Transvaal Lowveld. These animals ...
• Arthropod parasites of springbok, gemsbok, kudus, giraffes and Burchell's and Hartmann's zebras in the Etosha and Hardap Nature Reserves, Namibia 

  Horak, Ivan Gerard; Boomker, Jacob Diederik Frederik; Anthonissen, M.; Krecek, R.C.; Verwoerd, Daniel Wynand (Published by the Agricultural Research Council, Onderstepoort Veterinary Institute., 1992)

  A total of 48 springbok, 48 gemsbok, 23 kudus and 6 giraffes were examined for ticks and lice, while 9 Burchell's zebras and 6 Hartmann's mountain zebras were examined only for ticks. Springbok and gemsbok were shot in ...
• A light microscopical study of the intestinal tract of the Nile crocodile (Crocodylus niloticus, Laurenti 1768) 

  Kotze, Sanet H.; Van der Merwe, N.J.; Van Aswegen, G.; Smith, G.A.; Verwoerd, Daniel Wynand (Published by the Agricultural Research Council, Onderstepoort Veterinary Institute., 1992)

  Although the histology of the intestinal tract of Crocodylus niloticus is touched on in overall studies on reptilian intestinal tract, a more comprehensive light microscopical study on this area is lacking. Specimens for ...
• The Leucocytozoidae of South African birds : Passeriformes 

  Bennett, G.F.; Earle, R.A.; Peirce, Michael A.; Verwoerd, Daniel Wynand (Published by the Agricultural Research Council, Onderstepoort Veterinary Institute., 1992)

  The leucocytozoids of ten families of Passeriformes - Estrildidae, Fringillidae, Laniidae, Nectariniidae, Passeridae, Ploceidae, Promeropidae, Pycnonotidae, Sturnidae and Zosteropidae-are reviewed. Leucocytozoon roubaudi ...
• The Leucocytozoidae of South African birds: Caprimulgidae, Columbidae, Gruidae and Spheniscidae 

  Bennett, G.F.; Earle, R.A.; Peirce, Michael A.; Verwoerd, Daniel Wynand (Published by the Agricultural Research Council, Onderstepoort Veterinary Institute., 1992)

  Four species of Leucocytozoon, L. caprimulgi of the Caprimulgidae (nightjars), L. marchouxi of the Columbidae (pigeons and doves), L. grusi of the Gruidae (cranes) and L. tawaki of the Spheniscidae (penguins) are re-described. ...
• Deep dissections of the veins of the bovine head : unpublished work by Prof. J.M.W. Le Roux (1926-1991) 

  Smuts, M.M.S. (Malie Marie Sophie), 1933-; Bezuidenhout, A.J. (Abraham Johannes), 1942-; Verwoerd, Daniel Wynand; Seegers, Christine D. (Published by the Agricultural Research Council, Onderstepoort Veterinary Institute., 1992)

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