1965 Onderstepoort Journal of Veterinary Research, Volume 32, 1965

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

CONTENTS

*Volume 32: Number 1*

Bluetongue in cattle: typing of viruses isolated from cattle exposed to natural infections	Owen, NC, Du Toit, RM & Howell, PG	3

Review of Echinococcus species in South Africa	Verster, AJM	7

Biochemical studies on aflatoxicosis	Brown, JMM, Abrams, L	119

The pathological physiology of helminth infestations. 1. Ostertagia circumcincta	Horak, IG, Clark, R & Botha, JC	147

Studies on salivary lipase in young ruminants	Grosskopf, JFW	153

The chromososmes and neutrophil nuclear appendages of Hippopotamus amphibius Linnaeus 1758	Gerneke, WH	181


*Volume 32: Number 2*

A checklist and hostlist of the zoonoses occurring in mammals and birds in South and South West Africa	Neitz, WO	189

Author index		375

Subject index		375

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Subject index
(Pretoria : The Government Printer, 1965) Jansen B.C.
Author index
(Pretoria : The Government Printer, 1965) Jansen B.C.
A checklist and hostlist of the zoonoses occurring in mammals and birds in South and South West Africa
(Pretoria : The Government Printer, 1965) Neitz, W.O.; Jansen B.C.
I. A check-list and host-list of the zoonoses caused by viruses, Protophyta, Thallophyta, Protozoa, Arthropoda, Platyhelminthes and Nemathelminthes are listed in Tables 1 to 7. 2. Available information on their incidence and distribution as well as the authorities responsible for the investigations are included in this series of tables. 3. The literature references are recorded under the abovementioned headings at the end of the article.
Biochemical studies on aflatoxicosis
(Pretoria : The Government Printer, 1965) Brown, J.M.M.; Abrams, L.; Jansen B.C.
Biochemical studies have been made on liver tissue and blood from ducklings and various breeds of chickens maintained on standard rations containing 0·5 ppm of aflatoxin B₁. The results obtained from these birds were compared with those from birds of the same age maintained on groundnut-free mashes. Of the various breeds of chickens studied, only New Hampshires have been found to be susceptible to the effects of this level of aflatoxin. In the livers of affected chickens and ducklings a marked decrease in the activity of certain mitochondrial dehydrogenases and enzymes of the electron transfer chains or oxidative phosphorylation mechanisms is apparent. Mild to moderate anaemia, severe hypo-proteinaemia and grossly abnormal plasma protein electrophoretograms are presented by affected birds. It is believed that the suppression of protein synthesis observed and affecting the albumin fraction in particular, is due to a lowered rate of ATP synthesis consequent to mitochondrial injury. An increase in the activity of certain plasma enzymes, notably those of lactic dehydrogenase, aldolase and glutamic-oxalacetic- or glutamic-pyruvic transaminases, is also seen in these birds. This increase in the activity of plasma enzymes can be correlated with the severe hepatic lesions. The use of these various studies in the diagnosis of this condition, before hepatic lesions are evident, has been suggested. The ability of affected birds on rations containing 0·5 ppm of aflatoxin to recover rapidly when placed on toxin free rations is noted. Aflatoxin at these levels appears to have no cumulative effects, but no resistance is built up to its actions by tissues of birds exposed to it for long periods. Susceptible birds revealed no evidence of aflatoxicosis after prolonged feeding of dairy or poultry products obtained from cows or fowls kept on highly toxic rations. From the practical point of view there seems to be little danger inherent in the dietary use of such essential foods.
The chromososmes and neutrophil nuclear appendages of Hippopotamus amphibius Linnaeus 1758
(Pretoria : The Government Printer, 1965) Gerneke, W.H.; Jansen B.C.
The number of chromosomes of the hippopotamus is 2n = 36. Their morphology and grouping are shown in a karyogram. Sex determination is based on the x-y mechanism. Nuclear sexing on the appearance of neutrophil nuclear appendages is clearly defined owing to the presence of numerous drumsticks in females and their absence in males. The differentiation is further enhanced by the presence of peculiar vesicular appendages especially in neutrophils of males, although the possibility that their formation may be due to changes occurring during death, is not excluded.
Studies on salivary lipase in young ruminants
(Pretoria : The Government Printer, 1965) Grosskopf, Johannes Friedrich Wagner; Jansen B.C.
1. The presence of a lipase in the saliva of young calves, lambs and goat kids has been established. 2. The lipase acts only on triglycerides containing butyrate groups. 3. The optimum temperature for the activity of the salivary lipase lies between 37 and 42 ·5℃. It is inhibited completely by temperatures below 11℃ and above 58℃. 4. The optimum pH for the enzyme was found to be between pH 4 · 5 and 6 · 0. It was completely inhibited by pH below 2·4 and above 7·8. 5. A direct relationship exists between the potency of the lipase and the amount of acid it will produce in suitable substrates. 6. The lipolytic potency of the saliva of young calves and goats has been shown to decrease with increasing age. It decreased more rapidly in calves fed high roughage and low fat rations than in calves fed on whole milk only. In calves fed by the conventional methods, the enzyme disappeared from the saliva during the third month of life. 7. The secretion of the enzyme is stimulated by the calf sucking a teat or drinking milk. Sucking milk from a teat acts as a better stimulus than drinking milk from a bucket. Slower intake also stimulates lipase secretion. 8. The injection of cholinergic drugs caused increased flow of saliva with a higher lipase content. Anticholinesterases also stimulated its secretion but to a lesser degree. 9. The salivary lipase is secreted by the palatine salivary glands (glandulae veli palatini).
The pathological physiology of helminth infestations. 1. Ostertagia circumcincta
(Pretoria : The Government Printer, 1965) Horak, Ivan Gerard; Clark, R.; Botha, J.C.; Jansen B.C.
An experiment is described in which two sheep were artificially infested with 0. circumcincta and a third kept as an uninfested control. Plastic abomasal fistulae were inserted in these sheep and their erythrocytes were labelled with ⁵¹Cr. Radioactivity counts on blood and abomasal contents were done at regular intervals as well as other reactions being noted. The main findings were:- (i) No abnormal decrement in blood counts or increase in abomasal counts. (ii) An increase in abomasal pH and decrease in pepsin concentration. (iii) Anorexia and weight loss.
Review of Echinococcus species in South Africa
(Pretoria : The Government Printer, 1965) Verster, Anna Johanna Maria; Jansen B.C.
1. The nominate subspecies of E. granulosus (Batsch, 1786) is redesignated from the type locality, Europe. 2. Five subspecies of E. granulosus are described from South African carnivores: E. g. granulosus, E. g. africanus, E. g. felidis, E. g. lycaontis and E. g. ortleppi. 3. E. g. granulosus has so far only been recovered from the Transvaal; E. g. ortleppi appears to be restricted to the Transvaal; E. g. africanus occurs in the Orange Free State and the Transvaal; E. g. lycaontis and E. g. felidis like their definitive hosts are restricted to the Transvaal. 4. The domestic dog appears to be the most important source of infestation to domestic livestock. 5. Wild carnivores are important disseminators in various parts of the country; the black-backed jackal is probably as important as is the domestic dog in sheep rearing areas; the lion and the Cape hunting dog are of importance in restricted areas only; while the importance of the silver fox is negligible. 6. Domestic livestock are the most important source of infestation to carnivores. The role of wild herbivores as disseminators is not known, but they are probably of importance only in restricted areas.
Bluetongue in cattle : typing of viruses isolated from cattle exposed to natural infections
(Pretoria : The Government Printer, 1965) Owen, N.C.; Du Toit, R.M.; Howell, P.G.; Jansen B.C.
Bluetongue viruses were isolated from five clinically healthy bovines exposed to natural infection over two consecutive bluetongue seasons. The isolated viruses were typed by serum-virus neutralization and found to represent 11 of the established antigenic groups. Two isolations failed to be neutralized and may represent further antigenic types of bluetongue virus. No single virus type could be found to occur in the same bovine for two consecutive seasons and in most instances the particular virus type occurred in the blood ·of a bovine for a period of less than 14 days.

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