1981 Onderstepoort Journal of Veterinary Research, Volume 48, 1981

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Contentes Pages: Onderstepoort Journal of Veterinary Research, Vol ??, 19??

CONTENTS

*Volume 48: Number 1*

Observations on the transmission of Theileria mutans in South Africa	De Vos, AJ & Roos, JA	1

The efficacy of bacteriological procedures for the isolation of Brucella abortus from abattoir material	Herr, S & Roux, D	7

Some effects of ⁶⁰Co irradiation on Cowdria ruminantium in its tick host Amblyomma hebraeum Koch (Acarina: Ixodidae)	Spickett, AM, Bezuidenhout, JD & Jacobsz, CJ	13

A rapid quantitative colorimetric determination of blood acetone applied to the assessment of ketosis in fasted pregnant ewes	Van der Walt, JG, Procos, J & Hunter, G	15

The role of integumental glands in the social and mating behaviour of the hunting dog Lycaon pictus (Temminck, 1820)	Van Heerden, J	19

Ixodes (Afrixodes) matopi n. sp. (Acarina: Ixodidae) : a tick found aggregating on pre-orbital gland scent marks of the klipspringer in Zimbabwe	Spickett, AM, Keirans, JE, Norval, RAI & Clifford, CM	23

Ecological studies on Ixodes (Afrixodes) matopi Spickett, Keirans, Norval & Clifford, 1980 (Acarina: Ixodidae)	Colborne, J, Norval, RAI & Spickett, AM	31

Studies on the physiopathology of chronic obstructive pulmonary disease in the horse. IV. Blood gas and acid-base values at rest	Littlejohn, A & Bowles, F	37

Research communication:

The control of Simuliidae (Diptera, Nematocera) in South African rivers by modification of the water flow volume	Howell, CJ, Begemann, GJ, Muir, RW & Louw, P	47


*Volume 48: Number 2*

Identification of the serotype-specific and group-specific antigens of bluetongue virus	Huismans, H & Erasmus, BJ	51

A comparison of an Australian bluetongue virus isolate (CSIRO 19) with other bluetongue virus serotypes by cross-hybridization and cross-immune precipitation	Huismans, H & Bremer, CW	59

Levels of glucose, serum albumin and somatic cells before and during early stages of acute clinical mastitis artificially induced in cows by means of human strains of group-B streptococci (GBS) administered intracisternally	Giesecke, WH & Van den Heever, LW	69

Studies on schistosomiasis. 10. Development of Schistosoma mattheei in sheep infested with equal numbers of male and female cercariae	Van Rensburg, LJ & Van Wyk, JA	77

Rhipicephalus zambeziensis sp. nov., a new tick from eastern and southern Africa, together with a redescription of Rhipicephalus appendiculatus Neumann, 1901 (Acarina, Ixodidae)	Walker, JB, Norval, RAI & Corwin, MD	87

Attenuation of turkey meningo-encephalitis virus in BHK21 cells	Barnard, BJH & Geyer, HJ	105

An investigation into the toxic principle in eggs of the tick Amblyomma hebraeum	Prozesky, L, Neitz, AWH, Bezuidenhout, JD, Putterill, JF & Potgieter, DJJ	109

Attempts to transmit Anaplasma marginale with Hippobosca rufipes and Stomoxys calcitrans	Potgieter, FT, Sutherland, B & Biggs, HC	119

Isolation and significance of anaerobic bacteria isolated from cases of bovine mastitis	Du Preez, JH, Greeff, AS & Eksteen, N	123

Research communications:

Attempted transmission of canine ehrlichiosis to the vervet monkey (Cercopithecus pygerythrus)	Van Heerden, J & Goosen, DJ	127

A comparative study of the toxicity of Fusarium verticillioides (= F. moniliforme) to horses, primates, pigs, sheep and rats	Kriek, NPJ, Kellerman, TS & Marasas, WFO	129


*Volume 48: Number 3*

Brucellosis in free-living African buffalo (Syncerus caffer) : a serological survey	Herr, S & Marshall, C	133

Notes on African Haemaphysalis ticks. XIII. Identity of H. (Rhipistoma) cooleyi, a parasite of the rock hyrax in South Africa (Acarina: Ixodidae)	Hoogstraal, H & Wassef, HY	135

Recovery of helminths postmortem from equines. I. Parasites in arteries, subperitoneum, liver and lungs	Malan, FS, Reinecke, RK & Scialdo-Krecek, RC	141

The recovery of helminths postmortem from equines. II. Helminths and larvae of Gasterophilus from the gastro-intestinal tract and oestrids from the sinuses.	Malan, FS, Reinecke, RK & Scialdo-Krecek, RC	145

The isolation of Theileria? taurotragi in South Africa	De Vos, AJ & Roos, JA	149

Isolation and transmission of an unidentified Babesia sp. infective for cattle	Thomas, SE & Mason, TE	155

Paralysis in lambs caused by overdosing with parbendazole	Prozesky, L, Joubert, JPJ & Ekron, MD	159

Paracooperioides peleae gen. et sp. n. (Nematoda: Trichostrongylidae) from the vaal ribbok, Pelea capreolus (Forster, 1790)	Boomker, JDF, Horak, IG & De Vos, V	169

Research communications:

The influence of dithiosemicarbazone on the immunity of sheep to heartwater	Du Plessis, JL	175

Theileria? taurotragi : a probable agent of bovine cerebral theileriosis	De Vos, AJ, Bessenger, R & Banting, LF	177

Freeze-drying of Anaplasma marginale	Potgieter, FT & Bester, JB	179


*Volume 48: Number 4*

Schistosoma Weinland, 1858 from Hippopotamus amphibius Linnaeus, 1758 in the Kruger National Park	Pitchford, RJ & Visser, PS	181

The haemocytology and histology of the haemopoietic organs of South African freshwater fish. III. The leucocytes, plasma cells and macrophages of Clarias gariepinus and Sarotherodon mossambicus	Boomker, JDF	185

The haemocytology and histology of the haemopoietic organs of South African freshwater fish. IV. Ultrastructure of some cells of Clarias gariepinus and Sarotherodon mossambicus	Boomker, JDF	195

The development of Parafilaria bovicola in Musca xanthomelas and Musca lusoria	Nevill, EM	207

Studies on a bovine Babesia transmitted by Hyalomma marginatum rufipes Koch, 1844	Gray, JS & De Vos, AJ	215

The retention of Babesia bigemina infections by Boophilus decoloratus exposed to imidocarb dipropionate during engorgement	Gray, JS & Potgieter, FT	225

Studies on Haemonchus contortus. IV. The effect of Trichostrongylus axei and Ostertagia circumcincta on challenge with H. contortus	Reinecke, RK, De Villiers, IL & Bruckner, C	229

Studies on Haemonchus contortus. V. Chemoprophylaxis and its effect on worm egg counts and the haematocrit	Reinecke, RK, De Villiers, IL & Bruckner, C	235

Studies on the physiopathology of chronic obstructive pulmonary disease in the horse. V. Blood gas and acid-base values during exercise	Littlejohn, A & Bowles, F	239

First report of annual ryegrass toxicity in the Republic of South Africa	Schneider, DJ	251

Research communications:

Non-specific esterase isoenzymes of adult schistosomes from the hippopotamus (Hippopotamus amphibius)	Fripp, PJ	257

The relationship between the minimal and the 50% haemolytic dose in complement titrations	Herr, S, Pieterson, PM & Boshoff, JA	259

Author index		261

Subject index		265

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Now showing 1 - 20 of 45

Author index
(Pretoria : The Government Printer, 1981) Anonymous; Bigalke, R.D.; Cameron, Colin McKenzie; Gilchrist, Frances M.C.; Morren, A.J.; Verwoerd, Daniel Wynand; Walker, Jane B.; Verster, Anna Johanna Maria; Steyn, P.J.J.
Subject index
(Published by The Government Printer, Pretoria, 1981) Anonymous; Bigalke, R.D.; Cameron, Colin McKenzie; Gilchrist, Frances M.C.; Morren, A.J.; Verster, Anna J.M.; Verwoerd, Daniel Wynand; Walker, Jane B.; Steyn, P.J.J.
The relationship between the minimal and the 50% haemolytic dose in complement titrations
(Published by The Government Printer, Pretoria, 1981) Herr, S.; Pieterson, P.M.; Boshoff, J.A.; Bigalke, R.D.; Cameron, Colin McKenzie; Gilchrist, Frances M.C.; Morren, A.J.; Verster, Anna J.M.; Verwoerd, Daniel Wynand; Walker, Jane B.; Steyn, P.J.J.
The 50% spectrophotometric complement titration end-point (C'H₅₀) was found to be more reproducible than the 100% end-point. The relationship of the 100% end-point (MHD) to the (C'H₅₀) was 1:2, 5. The use of thrombin tubes induced clotting within 2 min and enabled the process of complement preparation to be completed well within 1 hour.
Non-specific esterase isoenzymes of adult schistosomes from the hippopotamus (Hippopotamus amphibius)
(Published by The Government Printer, Pretoria, 1981) Fripp, P.J.; Bigalke, R.D.; Cameron, Colin McKenzie; Gilchrist, Frances M.C.; Morren, A.J.; Verster, Anna J.M.; Verwoerd, Daniel Wynand; Walker, Jane B.; Steyn, P.J.J.
Extracts of adult schistosomes collected from Hippopotamus amphibius in the Kruger National Park gave alpha naphthyl acetate isoenzyme patterns after polyacrylamide gel electrophoresis that did not correspond with those of either Schistosoma mansoni or S. rodhaini.
First report of annual ryegrass toxicity in the Republic of South Africa
(Published by The Government Printer, Pretoria, 1981) Schneider, D.J.; Bigalke, R.D.; Cameron, Colin McKenzie; Gilchrist, Frances M.C.; Morren, A.J.; Verster, Anna J.M.; Verwoerd, Daniel Wynand; Walker, Jane B.; Steyn, P.J.J.
The occurrence of annual ryegrass toxicity (ARGT) in sheep and cattle is reported for the first time in South Africa. To date it has been diagnosed conclusively in South African Mutton Merino sheep on a farm in the Caledon district and in cattle on 3 farms, 2 of which are situated in the Bredasdorp district and 1 in the Ceres district. It is a neurological disease characterized by symptoms of tremor, ataxia, intermittent epileptiform seizures, nystagmus, opisthotonus, abortions and high mortality. The history, clinical signs and experimental reproduction of the disease as well as the pathology of 4 experimental and 10 natural cases in sheep and 2 in cattle are described.
Studies on the physiopathology of chronic obstructive pulmonary disease in the horse. V. Blood gas and acid-base values during exercise
(Published by The Government Printer, Pretoria, 1981) Littlejohn, A.; Bowles, Felicity; Bigalke, R.D.; Cameron, Colin McKenzie; Gilchrist, Frances M.C.; Morren, A.J.; Verster, Anna J.M.; Verwoerd, Daniel Wynand; Walker, Jane B.; Steyn, P.J.J.
The haemoglobin concentration, the partial pressures of oxygen and carbon dioxide, the oxygen content and the pH were determined in the arterial and mixed venous blood of 5 normal and 3 horses with chronic obstructive pulmonary disease (COPD) at 3 stages of an exercise distance of 1200 m. Arterial and mixed venous samples were collected simultaneously by means of an automatic technique during the walk, trot and gallop at 0-100 m, at 500-600 m and at 1100-1200 m. The standard bicarbonate and the lactic and pyruvic acid concentrations were also determined in arterial and mixed venous blood. Highly significant changes in the mean values of P⊽C0₂ , 0₂ content and Δ a-⊽ 0₂ content occurred during exercise in COPD subjects, and significant changes in P⊽O₂ and Δ a-⊽ 0₂ content occurred during exercise in normal subjects. We concluded that COPD subjects compensated for respiratory dysfunction during exercise by extracting more oxygen from the blood than did normal horses. There was a highly significant correlation between the changes in standard bicarbonate and the changes in lactic acid concentration during exercise in both normal and COPD subjects. This led to the conclusion that lactic acid production was primarily, but not completely, responsible for the metabolic acidosis of exercise in horses.
Studies on Haemonchus contortus. V. Chemoprophylaxis and its effect on worm egg counts and the haematocrit
(Published by The Government Printer, Pretoria, 1981) Reinecke, R.K.; De Villiers, I.L.; Bruckner, Christel; Bigalke, R.D.; Cameron, Colin McKenzie; Gilchrist, Frances M.C.; Morren, A.J.; Verster, Anna J.M.; Verwoerd, Daniel Wynand; Walker, Jane B.; Steyn, P.J.J.
A group of 12 10-month-old, worm-free Merino lambs were given a single injection of disophenol at 10 mg/kg. This group and another group of 12 worm-free lambs were infested with infective larvae of Haemonchus contortus 1- 3 times a week with a maximum dose of 4000/week from 0-91 days. From 95-168 days the dose was increased to a maximum of 6000/week. Every 7 days faeces were examined for worm eggs and blood samples for haematocrit (Ht). Worm egg counts in the controls rose from 21-56 days, fluctuated, and rose to another peak at 84 days, while the Ht fell from 28 days to rise again after 105 days. In the group treated with disophenol egg counts were negative until 161 days and Ht remained at normal values throughout.
Studies on Haemonchus contortus. IV. The effect of Trichostrongylus axei and Ostertagia circumcincta on challenge with H. contortus
(Published by The Government Printer, Pretoria, 1981) Reinecke, R.K.; De Villiers, I.L.; Bruckner, Christel; Bigalke, R.D.; Cameron, Colin McKenzie; Gilchrist, Frances M.C.; Morren, A.J.; Verster, Anna J.M.; Verwoerd, Daniel Wynand; Walker, Jane B.; Steyn, P.J.J.
Worm-free Merino yearlings were dosed with either a mixture of infective larvae of Trichostrongylus axei and Ostertagia circumcincta or with O. circumcincta only, and challenged 90-93 days later with infective larvae of Haemonchus contortus. Neither of these methods protected sheep against challenge and slight protection was afforded sheep predosed with T. axei and O. circumcincta and challenged with a trickle dose of H. contortus.
The retention of Babesia bigemina infections by Boophilus decoloratus exposed to imidocarb dipropionate during engorgement
(Published by The Government Printer, Pretoria, 1981) Gray, J.S.; Potgieter, F.T.; Bigalke, R.D.; Cameron, Colin McKenzie; Gilchrist, Frances M.C.; Morren, A.J.; Verster, Anna J.M.; Verwoerd, Daniel Wynand; Walker, Jane B.; Steyn, P.J.J.
Babesia bigemina was retained in the vector Boophilus decoloratus for a complete generation despite the use of the babesicide, imidocarb dipropionate, to prevent reinfection. This drug did not sterilize ticks of the B. bigemina infection as has been suggested for B. bovis.
Studies on a bovine Babesia transmitted by Hyalomma marginatum rufipes Koch, 1844
(Published by The Government Printer, Pretoria, 1981) Gray, J.S.; De Vos, A.J.; Bigalke, R.D.; Cameron, Colin McKenzie; Gilchrist, Frances M.C.; Morren, A.J.; Verster, Anna J.M.; Verwoerd, Daniel Wynand; Walker, Jane B.; Steyn, P.J.J.
A Babesia sp. was recently observed in Hyalomma marginatum rufipes and found to be transmissible to bovines. Further observations were carried out on this parasite and a study made of the morphology of stages in both erythrocytes and tick haemolymph. Apart from Babesia divergens intra-erythrocytic parasites were not readily distinguishable from bovine Babesia spp. Merozoites in tick haemolymph morphologically resembled those of Babesia bigemina, but they were significantly larger. This Babesia sp. proved to be highly infective for adult H. m. rufipes, with transmission taking place transovarially and next generation nymphae and adults transmitting the infection. Features of the infection were its very low pathogenicity, even in splenectomized animals, and the tendency of parasitized erythrocytes to accumulate in capillaries. Serologically, this species could be differentiated from Babesia bigemina, B. divergens, B. bovis and B. major. A serological survey of 25 farms showed a wide distribution of this species in South Africa and its high rate of transmission on most properties. It was concluded that this is a true but hitherto undescribed bovine Babesia sp. and the name Babesia occultans n. sp. is proposed.
The development of Parafilaria bovicola in Musca xanthomelas and Musca lusoria
(Published by The Government Printer, Pretoria, 1981) Nevill, E.M.; Bigalke, R.D.; Cameron, Colin McKenzie; Gilchrist, Frances M.C.; Morren, A.J.; Verster, Anna J.M.; Verwoerd, Daniel Wynand; Walker, Jane B.; Steyn, P.J.J.
Artificially infected adult flies were used in this study. In both Musca species, P. bovicola developed in the fat-body cells, mainly of the abdomen. Escape from the midgut and penetration of the fatbody cell was possibly achieved by use of the cephalic hook of the microfilaria. At 27 °C, development to the 3rd larval stage took 9 days, but maximum length was only reached after 11 days. Sharp increases in larval length took place on Days 6-7 and on Day 9. These sudden increases possibly indicate moults to the 2nd and 3rd larval stages respectively. During larval development the fat-body cell increased markedly in size to form a thin-walled capsule around the larva. On reaching the 3rd stage, larvae escaped from the capsules and migrated to the head cavity and proboscis.
The haemocytology and histology of the haemopoietic organs of South African freshwater fish. IV. Ultrastructure of some cells of Clarias gariepinus and Sarotherodon mossambicus
(Published by The Government Printer, Pretoria, 1981) Bigalke, R.D.; Cameron, Colin McKenzie; Gilchrist, Frances M.C.; Morren, A.J.; Verster, Anna J.M.; Verwoerd, Daniel Wynand; Walker, Jane B.; Steyn, P.J.J.; Boomker, Jacob Diederik Frederik
This paper describes the ultrastructure of several cells found in the blood and haemopoietic tissues of the catfish (Clarias gariepinus) and the Mozambique bream (Sarotherodon mossambicus). The cells are haemocytoblasts, small lymphoid haemoblasts, thrombocytes, monocytes, lymphocytes, developing and mature neutrophilic granulocytes, plasma cells and macrophages. The various organelles normally found in mammalian haemocytes, plasma cells and macrophages were observed in those of fish. With the exception of the mature erythrocytes, which resemble the normoblasts of mammals, the various cells show distinct similarities to those of other fish species as well as of mammals.
The haemocytology and histology of the haemopoietic organs of South African freshwater fish. III. The leucocytes, plasma cells and macrophages of Clarias gariepinus and Sarotherodon mossambicus
(Published by The Government Printer, Pretoria, 1981) Bigalke, R.D.; Cameron, Colin McKenzie; Gilchrist, Frances M.C.; Morren, A.J.; Verster, Anna J.M.; Verwoerd, Daniel Wynand; Walker, Jane B.; Steyn, P.J.J.; Boomker, Jacob Diederik Frederik
The various leucocytes, plasma cells and macrophages are described and illustrated. Eosinophils and basophils are lacking in Clarias gariepinus but present in Sarotherodon mossambicus. The leucocytes of C. gariepinus resemble those found in mammals, as do the plasma cells and macrophages of both species. A possible mechanism for their formation is postulated.
Schistosoma Weinland, 1858 from Hippopotamus amphibius Linnaeus, 1758 in the Kruger National Park
(Published by The Government Printer, Pretoria, 1981) Pitchford, R.J.; Visser, P.S.; Bigalke, R.D.; Cameron, Colin McKenzie; Gilchrist, Frances M.C.; Morren, A.J.; Verster, Anna J.M.; Verwoerd, Daniel Wynand; Walker, Jane B.; Steyn, P.J.J.
Adults of Schistosoma edwardiense Thurston, 1964, were recovered from Hippopotamus amphibius in the Kruger National Park. Small round to oval Schistosoma margrebowiei-like eggs, presumed to be those of S. edwardiense, were found fairly frequently in the faeces of infected hippopotami together with a few Schistosoma haematobium-like eggs the identity of which remains uncertain. Biomphalaria sp., exposed to the droppings of infected hippopotami, shed cercariae thought to be those of S. edwardiense. No evidence of schistosoma adults was found at necropsy in rodents exposed to these cercariae. The parasite appears to be host specific to the hippopotamus. Arguments, based on biological and anatomical characteristics are put forward regarding Schistosoma hippopotami Thurston, 1963 as synonymous with Schistosoma mansoni.
Paralysis in lambs caused by overdosing with parbendazole
(Published by The Government Printer, Pretoria, 1981) Joubert, J.P.J.; Ekron, M.D.; Bigalke, R.D.; Cameron, Colin McKenzie; Gilchrist, Frances M.C.; Morren, A.J.; Verster, Anna J.M.; Verwoerd, Daniel Wynand; Walker, Jane B.; Steyn, P.J.J.; Prozesky, Leon
An experiment was undertaken to determine whether an overdose of the anthelmintic parbendazole could cause paralysis in lambs when given to ewes during the early stages of pregnancy. Out of a total of 68 lambs, born from ewes treated at various stages of gestation with parbendazole at 180 mg/kg, 5 showed the paralysis syndrome, 5 showed skeletal deformities, 2 were ataxic, while 1 foetus was aborted. The ewes giving birth to paralysed lambs had been treated with parbendazole at 30, 32, 37 and 53 days of gestation. Cerebral hypoplasia was observed in 2 of these lambs, while 2 others showed internal hydrocephaly. Histopathological lesions observed in the lambs with cerebral hypoplasia included gliosis and areas of encephalomalacia in the cerebral white matter. Lesions present in the spinal cords of the 2 ataxic lambs included pydromyelia, syringomyelia, duplication of the spinal canal and an abnormal position of the canal. This is the first report describing brain lesions in lambs as a result of an overdose of parbendazole.
Theileria? taurotragi : a probable agent of bovine cerebral theileriosis
(Published by The Government Printer, Pretoria, 1981) De Vos, A.J.; Bessenger, R.; Banting, L.F.; Bigalke, R.D.; Cameron, Colin McKenzie; Gilchrist, Frances M.C.; Morren, A.J.; Verster, Anna J.M.; Verwoerd, Daniel Wynand; Walker, Jane B.; Steyn, P.J.J.
A case of bovine cerebral theileriosis was confirmed at autopsy on a farm where 4 animals out of 70 died. All were less than 2 years old and all showed nervous signs. Serologically, no evidence was found of Theileria mutans or the Theileria parva group in young animals born on the farm. Six out of 13 calves 6-9 months of age were, however, serologically positive for Theileria? taurotragi and it was concluded this species was the probable cause of death of the 4 animals.
Freeze-drying of Anaplasma marginale
(Published by The Government Printer, Pretoria, 1981) Potgieter, F.T.; Bester, J.B.; Bigalke, R.D.; Cameron, Colin McKenzie; Gilchrist, Frances M.C.; Morren, A.J.; Verster, Anna J.M.; Verwoerd, Daniel Wynand; Walker, Jane B.; Steyn, P.J.J.
Heparinized whole blood, heavily parasitized with Anaplasma marginale, was collected from 3 splenectomized oxen. Buffered lactose peptone (BLP) was added in equal volumes as a stabilizer and the mixture lyophilized in 2 ml aliquots after rapid freezing. The dried material was reconstituted with 2 ml sterile water and inoculated without delay. The product remained infective for at least 6 months when stored in an ordinary household deep-freeze unit.
The influence of dithiosemicarbazone on the immunity of sheep to heartwater
(Published by The Government Printer, Pretoria, 1981) Du Plessis, J.L.; Bigalke, R.D.; Cameron, Colin McKenzie; Gilchrist, Frances M.C.; Morren, A.J.; Verster, Anna J.M.; Verwoerd, Daniel Wynand; Walker, Jane B.; Steyn, P.J.J.
Four out of 9 sheep, immune to heartwater and subsequently treated with gloxazone, showed a febrile reaction when they were challenged 6 months later, but the same number of untreated controls also developed this reaction. In a second group of treated immune animals challenged after 9 months, 8 out of 8 showed a febrile reaction, whereas only 3 out of 8 controls reacted. Furthermore, the blood of one of the 4 sheep that reacted to challenge at 6 months was infective to a susceptible sheep inoculated with it, whereas that of 4 out of the 8 challenged at 9 months was infective.
Paracooperioides peleae gen. et sp. n. (Nematoda: Trichostrongylidae) from the vaal ribbok, Pelea capreolus (Forster, 1790)
(Published by The Government Printer, Pretoria, 1981) De Vos, Valerius; Bigalke, R.D.; Cameron, Colin McKenzie; Gilchrist, Frances M.C.; Morren, A.J.; Verster, Anna J.M.; Verwoerd, Daniel Wynand; Walker, Jane B.; Steyn, P.J.J.; Boomker, Jacob Diederik Frederik; Horak, Ivan Gerard
A new genus and species of trichostrongylid nematode, Paracooperioides peleae, was collected from the small intestines of vaal ribbok, Pelea capreolus (Forster, 1790), from the Bontebok National Park, Swellendam, Cape Province. These nematodes are small and slender with a small cephalic inflation. The cuticle bears numerous transverse striations which are more pronounced anteriorly. The dorsal ray is long and is similar to that of Gazellostrongylus Yeh, 1956, and Cooperioides hepaticae Ortlepp, 1938, but differs in that it bifurcates in its distal quarter. Each branch divides again, giving rise to a thinner, outer branch and a thicker inner branch. The latter recurves upon itself to form a small, elongated knob. The spicules of Paracooperioides peleae resemble those of C. hepaticae but can be differentiated from them in that they bear small lateral barbs on their tips. Ten longitudinal ridges, supported by sclerotized rods, are present at the middle of the body. In transverse section, Paracooperioides peleae is intermediate between Cooperioides Daubney, 1933 and Paracooperia Travassos, 1935.
Isolation and transmission of an unidentified Babesia sp. infective for cattle
(Published by The Government Printer, Pretoria, 1981) Thomas, Shan E.; Mason, T.E.; Bigalke, R.D.; Cameron, Colin McKenzie; Gilchrist, Frances M.C.; Morren, A.J.; Verster, Anna J.M.; Verwoerd, Daniel Wynand; Walker, Jane B.; Steyn, P.J.J.
Engorged adult female ticks submitted from farms in South Africa were routinely screened for protozoan parasites by examination of haemolymph smears. An unidentified Babesia sp. was found in Hyalomma marginatum rufipes and its transmission to susceptible cattle was achieved both biologically (tick feeding) and mechanically (injection of infected blood). Attempts to transmit this species to susceptible rabbits and a horse using similar methods did not produce evidence of infection. This Babesia sp. was of low pathogenicity, even in splenectomized cattle. Morphologically, intra-erythrocytic piroplasms and merozoites in tick haemolymph resembled other bovine Babesia spp. in many respects. Although it could be classified as a large Babesia, it was intermediate in size between the other species.

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