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Characterization of a pigeon paramyxovirus (PPMV-1) isolated from chickens in South Africa : research communication
2004
C. Abolnik | R.F. Horner | R. Maharaj | G.J. Viljoen
A paramyxovirus with a thermostability of 60 min (typical of velogenic viruses) and a mean death time of > 90 h (typical of lentogenic viruses) was isolated from layers near Mooi River, South Africa. Our results, based on comparative nucleotide sequence data indicated that the virus is pigeon paramyxovirus 1 (PPMV-1), a variant of Newcastle disease virus. The F0 cleavage site contains a 112RRKKRF117 motif, and the virus had 98 % sequence identity with PPMV-1 strains from the Far East. PPMV-1 was last reported in South Africa during the 1980s, with this being the first report of PPMV-1 isolated from chickens in South Africa.
Mostrar más [+] Menos [-]Reference serum protein and lipoprotein fractions of ostriches (Struthio camelus<i/>) in Turkey : research communication
2004
U. Polat | M. Cetin | O. Turkyilmaz | A. Yalcin
The aim of this study was to determine for reference purposes the values of serum albumin, a1-globulin, a2-globulin, b-globulin, g-globulin, and a-lipoprotein (high density lipoprotein), pre-b-lipoprotein (very low density lipoprotein) and b-lipoprotein (low density lipoprotein) fractions of normal ostriches (Struthio camelus) in Turkey. Five male and five female ostriches, 18 months old, were used. All the ostriches were fed on a diet that contained 15.14 % crude protein and 2 950 Kcal/kg of metabolizable energy. The serum protein and lipoprotein fractions were measured using agarose gel electrophoresis. The fractions were found to be 60.96 % albumin, 0.24% a1-globulin, 15.91 % a2-globulin, 13.34 % b-globulin, 9.55 % g-globulin, 53.77 % HDL, 0.60 % VLDL and 48.09 % LDL.
Mostrar más [+] Menos [-]The occurrence of Contracaecum<i/> sp. larvae (Nematoda : Anisakidae) in the catfishClarias gariepinus<i/> (Burchell) from Lake Chivero, Zimbabwe
2004
M. Barson
Clarias gariepinus were collected from Lake Chivero, Zimbabwe, and examined for nematode parasites from November 2000 to May 2002. Of the 202 specimens collected, 42.6 % were infected with third-stage larvae of Contracaecum sp. in the body cavity. The intensity of the infection was 1-7 worms per fish (mean intensity = 2.2). Seasonal variation in the prevalence of the parasite was not obvious and there was no significant difference in the prevalence of infection between males and females (c2 = 2.228; P > 0.05). No significant relationship between host size and prevalence was established. There was also no significant relationship between intensity and the body condition factor (r = 0.11; P > 0.05). The low parasite prevalence may have been caused by the disruption of the infection cycle since piscivorous birds, which are the final hosts of the parasite, do not feed on C. gariepinus in Lake Chivero.
Mostrar más [+] Menos [-]The effect of dexamethasone and promethazine in combination with buparvaquone in the management of East Coast fever
2004
M. Gwamaka | J.A. Matovelo | M.M.A. Mtambo | G.K. Mbassa | R.M. Maselle | S. Boniphace
The effects of dexamethasone and promethazine on the amelioration of pulmonary oedema in East Coast fever were investigated. The clinical effects of these drugs were further investigated when used in conjunction with the antitheilerial drug, buparvaquone. In the first experiment, 15 crossbred (Friesian x Zebu) steers were divided into four groups. With the exception of the animals in group IV, that served as a control group all the others were infected with Theileria parva sporozoites. On the second day of the febrile reaction, the steers in groups I and II were treated with dexamethasone (0.1 mg/kg) and promethazine (1 mg/kg), respectively. Group III steers served as the infected untreated controls. On the fifth day of the febrile reaction the animals in groups I, II and III were infused intravenously with tattoo ink suspension and 1 h later sacrificed for post-mortem examination and tissue sampling. The clinical picture indicated that both drugs significantly mitigated dyspnoea and the post mortem examination revealed a significant reduction in morphological changes. Tattoo ink particle count reflected a significant (P < 0.01) reduction in vascular leakage in the treated animals, with promethazine being significantly (P < 0.05) more effective than dexamethasone in this respect. In the second experiment, 18 steers were infected with T. parva sporozoites, and then were randomly allotted into three groups each of which contained six animals. After the onset of ECF clinical signs, the animals in the first two groups were treated with buparvaquone in combination with either dexamethasone (group I) or promethazine (group II), and the third group was treated with buparvaquone alone. The results indicated that all the animals in groups I, II and III recovered well and no significant differences were observed in clinical disposition between the groups. Two months later, serum samples were collected from the refractory animals and demonstrated the presence of antibodies against T. parva. When the animals were subsequently artificially challenged with T. parva, none of them succumbed to clinical disease. The same T. parva stabilate stock was used in both experiments and it proved to be infective in a separate batch of steers.
Mostrar más [+] Menos [-]Parasites of domestic and wild animals in South Africa. XLIV. Fleas (Insecta : Siphonaptera : Pulicidae) collected from 15 carnivore species
2004
I.G. Horak | J.-C. Beaucournu | L.E.O. Braack
Fleas were collected from 61 wild carnivores belonging to 13 species in various nature reserves and on farms, two feral domestic cats in a nature reserve and a domestic dog in the city of Johannesburg. Eleven flea species, including two subspecies of one of these, belonging to six genera were recovered. Amongst these only Ctenocephalides felis felis and Ctenocephalides felis strongylus are considered specific parasites of carnivores. The remaining ten species normally infest the prey animals of the various carnivores.
Mostrar más [+] Menos [-]Larval biology of Rhipicephalus (Boophilus) decoloratus (Acarina : Ixodidae) in Free State Province, South Africa : research communication
2004
M.S. Phalatsi | L.J. Fourie | I.G. Horak
The objective of this study was to determine certain aspects of the biology of Rhipicephalus (Boophilus) decoloratus larvae under laboratory and field conditions. Larvae allowed 48 h to select a vertical questing substrate preferred 90 cm rods in length to those of 60 or 30 cm, while in a separate experiment migration from rods 5 cm or 25 cm in length to rods 45 cm in length continued between 48 h and 72 h after larval release. Hatching of the larval progeny of engorged female ticks exposed to ambient field temperatures during the period June to August, occurred synchronously during the third or fourth week of November. With a single exception, larvae that hatched during November and between April and July survived for 38 days or longer, while those that hatched from December to March survived for 31 days or less. Questing larvae were present on vegetation throughout the year, with most being recovered during January and February. Parasitic larvae were present on cattle from October to May with most being collected during January and February.
Mostrar más [+] Menos [-]Preliminary survey of ticks (Acari : Ixodidae) on cattle in northern Sudan
2004
D.A. Salih | S.M. Hassan | A.M. El Hussein | F. Jongejan
In a cross sectional survey conducted during the period June 2001 to July 2002, the geographical distribution of ticks on cattle in the Sudan was determined. Seventeen locations were surveyed from Northern, Central, Eastern, Western, Blue Nile and White Nile Provinces. Total body collections of ticks were made from 20 cattle at each location. Four tick genera and 11 species were identified. The tick species collected included Amblyomma lepidum, Amblyomma variegatum, Boophilus decoloratus, Hyalomma anatolicum anatolicum, Hyalomma dromedarii, Hyalomma impeltatum, Hyalomma marginatum rufipes, Hyalomma truncatum, Rhipicephalus evertsi evertsi, Rhipicephalus sanguineus group and Rhipicephalus simus simus. Major ecological changes have occurred due to extensive animal movement, deforestation, desertification and establishment of large mechanized agricultural schemes. These factors have certainly affected the distribution of ticks and tick-borne diseases in the Sudan. The absence of A. variegatum and A. lepidum in northern Sudan was not surprising, since these tick species are known to survive in humid areas and not in the desert and semi-desert areas of northern Sudan. The absence of B. annulatus in northern and central Sudan is in accordance with the finding that this tick species is restricted to the southern parts of the central Sudan. The presence of H. anatolicum anatolicum in Um Benin in relatively high abundance is an interesting finding. The present finding may indicate that the southern limit of this species has changed and moved southwards to latitude 13o N. It is concluded that major changes in tick distribution have taken place in the Sudan
Mostrar más [+] Menos [-]Linognathus weisseri<i/> n. sp. (Phthiraptera : Linognathidae) of impalas, Aepyceros melampus<i/> : description and biology
2004
L.A. Durden | I.G. Horak
The adult male and female and first instar nymph of the sucking louse Linognathus weisseri n. sp. are described. This louse was collected from impalas, Aepyceros melampus, at three localities in Limpopo Province, and at three in Mpumalanga Province, South Africa. Although it usually accounted for only a small proportion of the total louse burden, its overall prevalence exceeded 27 %. Its prevalence on adult male impalas (9 %) was significantly lower (P = 0.004) than that on adult females (39 %), but did not differ among age classes. However, the intensity of L. weisseri infestation was higher on lambs than on yearlings and adults, and peaked on impalas in late winter to early summer. Five species of lice are now known to parasitize impalas and a key for distinguishing adults of these species is included.
Mostrar más [+] Menos [-]Parasites of South African wildlife. XVIII. Cooperia pigachei<i/> n. sp. (Nematoda : Cooperiidae) from the mountain reedbuck, Redunca fulvorufula<i/> (Afzelius, 1815)
2004
J. Boomker | W.A. Taylor
A new species of Cooperia, for which the name Cooperia pigachei n. sp. is proposed, was recovered from a mountain reedbuck, Redunca fulvorufula, from the Sterkfontein Dam Nature Reserve, Free State Province, and is described and illustrated. It is close to Cooperia neitzi Mönnig, 1932 and the South African race of Cooperia rotundispiculum in having more than 14 longitudinal cuticular ridges and in that the lateral cervical synlophe is of the closed type. The new species differs from all the other species of the genus in that the lateral branches of the dorsal ray are large and T-shaped. The spicules are robust, over 0.3 mm long and have large, curved shoes on their tips.
Mostrar más [+] Menos [-]The point prevalence of gastro-intestinal parasites in calves, sheep and goats in Magadi division, south-western Keny
2004
M.W. Maichomo | J.M. Kagira | T. Walker
Helminths cause great economic loss in livestock in Africa, and can be categorized as either direct or indirect losses. Arid and semi-arid lands (ASAL) in Kenya comprise 71 % of total land area and harbour the largest population of cattle, sheep and goats. However, little information on the distribution and impact of gastro-intestinal (GIT) parasitism in these animals is available. This survey was conducted to establish the prevalence of GIT parasites infecting calves, sheep and goats and their relative importance in Magadi division, which is semi-arid. Faecal samples were obtained directly from the rectum of 109 calves, 133 goats and 20 sheep and submitted to the laboratory for faecal worm egg counts, and coccidial oocysts examination using a modified McMaster method. The significance of differences in mean egg count per gram (epg) between animal species and herds (farms) were assessed using analysis of variance. The overall prevalence of nematodes in the calves, sheep and goats was 69.2 %, 80 % and 82 %, respectively. About 10 % of sheep and goats had epgs higher than 1 000, the remainder having light to moderate infections. The overall prevalence of coccidial oocysts in calves, sheep and goats was 30 %, 44 % and 45 %, respectively. Poor productivity in ASAL areas, where nutrition is often poor, is likely to be pronounced in the presence of parasite infections. These findings indicate that viable internal parasite control should be implemented in the study area in order to increase the productivity of the livestock there.
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