Seasonal abundance of adult ixodid ticks infesting cattle belonging to resource-limited farmers in the north-eastern Free State Province of South Africa

A study was undertaken to determine the seasonal abundance of the ticks infesting cattle owned by resource-limited farmers in the north-eastern Free State Province of South Africa. Infestations of Boophilus decoloratus Koch, 1844, Rhipicephalus evertsi evertsi Neumann, 1897, Rhipicephalus follis Donitz, 1910, Rhipicephalus gertrudae Feldman-Muhsam, 1960 and Rhipicephalus warburtoni Walker & Horak, 2000, were monitored on cattle of mixed breeds at monthly intervals from May 1998 to April 1999. High tick intensity on the cattle was observed between March and June, with a peak in May to June 1998 for B. decoloratus and R. evertsi evertsi. Few ticks from the other three species were recovered from the cattle. Small peaks in November to December 1998 for R. warburtoni, and in December 1998 for R. follis and R. gertrudae were observed. Following the winter (June to August), numbers of B. decoloratus declined markedly, while those of R. evertsi evertsi and other rhipicephalids increased. These results represent the first published information on ticks of veterinary importance infesting cattle in the north-eastern part of the Free State Province.     

A survey of tick control methods used by resource-poor farmers in the Qwa-Qwa area of the eastern Free State Province, South Africa

A survey conducted in five villages in a resource-poor farming community in Qwa-Qwa, using the rapid rural appraisal technique and a questionnaire survey, showed that a significant proportion of the farmers (84%) use traditional or alternative methods to control ectoparasites, while 16% use commercial acaricides (chi2 = 7.1; P < or = 0.05). Alternative control methods included the use of used engine oil, household disinfectant and paraffin. Killing of ticks was the main reason for control (40%), with disease control being second (20%). Other reasons given for controlling ticks were to prevent damage to teats, to provide animals with a clean appearance and to protect hides. Some 40% of farmers were aware of the effects of ticks on their animals. There is a need for farmer education that will provide information on integrated tick management and its advantages over absolute reliance on commercial acaricides.     

Gastro-intestinal parasites of cattle in the communal grazing system of Botshabelo in the Free State.

Twelve Bonsmara tracer calves (aged 6-12 months) were used to monitor helminth infections in the communal farming system of Botshabelo in the Free State. One calve was slaughtered each month from December 1995 to November 1996 and processed for helminth recovery. All the calves harboured worms, but the numbers were always low. The order of prevalence of the major parasites was Trichostrongylus axei, Haemonchus placei, Cooperia punctata and Cooperia pectinata.     

A survey of gastrointestinal parasites in cattle of southeastern Nigeria

This paper presents the results of a survey of 1021 cattle in the southeastern area of Nigeria during August–October 1990 (wet season) and January–March 1991 (dry season) to study the effects of season, ecological zone, management system, breed and age on the occurrence of gastrointestinal parasites (GIP).

Strongyles (mainly Haemonchus spp.) were the commonest GIP (prevalence 47.8%; 95% CI; 44.8–51%; mean eggs per gram (epg) 387 ± SE 21.3) followed by coccidia (3.6%; 95% CI, 2.6–5%; mean oocysts per gram (opg) 2077 ± 778.4). The prevalence of other parasites encountered was comparatively very low. More infections were present in the wet than in the dry season (P<0.01). Whereas a higher prevalence (P<0.01) of strongyle infection was recorded in nomadic herds, that of coccidia was higher in sedentary herds. The prevalence of strongyle infection was lower in young animals (P<0.05), but they had higher epg (P<0.01) and also higher coccidia prevalences (P<0.01) than adults. Friesian and N'dama breeds under improved management in modern farms had lower strongyle and higher coccidia infections compared with zebu and muturu kept under the traditional management system The distribution of infection by ecological zone did not show any consistent trend, and this was attributed to the uneven distribution of the cattle breeds amongst the different zones.     

Serological survey of Babesia bovis and Babesia bigemina in cattle in South Africa

A total of 719 serum samples collected from clinically healthy cattle from eight provinces located in different districts of South Africa were examined by the indirect enzyme-linked immunosorbent assay (ELISA) and the standard indirect fluorescent antibody test (IFAT) to determine the serological prevalence of Babesia bovis and Babesia bigemina. The results showed that 35.3% and 39.7% of cattle were positive for B. bovis and 30% and 36.5% were positive for B. bigemina antibodies on ELISA and IFAT, respectively. Mixed infections were detected in 18.2% and 26.3% of the samples using ELISA and IFAT, respectively. Consequently, the ELISAs with recombinant B. bovis spherical body protein-4 (BbSBP-4) and B. bigemina C-terminal rhoptry-associated protein-1 (BbigRAP-1/CT) were proven to be highly reliable in the serological diagnoses of bovine babesiosis in South African cattle, as evidenced by the significant concordance rates when the results were compared to those of IFAT. Moreover, the serological prevalence was significantly different among the tested provinces, in which the ranges exhibited between 15% and 73% for B. bovis infection and between 13% and 54% for B. bigemina infection. High sero-positive rates were present in Mpumalanga and KwaZulu-Natal provinces, while the lowest rate was in the North West province. Our data provide important information regarding the current seroprevalence of bovine babesiosis in South Africa, which might be beneficial in developing rational strategies for disease control and management.     

A survey of feline babesiosis in South Africa

South Africa appears to be the only country where feline babesiosis is a significant clinical entity in domestic cats. Little is known about its epidemiology or the clinical challenges facing practitioners. A questionnaire posted to 1760 South African veterinarians was returned by 16%, representing approximately 40% of practices. Just over half reported seeing feline babesiosis, with most cases occurring in the coastal areas of the Western Cape, Eastern Cape and KwaZulu-Natal Provinces. Overall incidence is highest in summer, but seasonality is less pronounced in non-seasonal and winter rainfall areas. No age, breed or sex predisposition was identified. Weight loss, weakness, anaemia, fever and icterus are common clinical findings. Complications include hepatopathy, renal failure, pulmonary oedema, cerebral signs, immune-mediated haemolytic anaemia and concurrent infections. The antibabesial drug of choice is primaquine phosphate. Response to therapy is generally good, but recurrence and chronic infections were identified as problems. The average mortality rate was 15%. Approximately 3000 cases are seen annually by the respondents, at an estimated cost of R750 000 to the owners. Feline babesiosis is a significant problem in South Africa, and further investigations of taxonomic status, concurrent infections, chemotherapy, complications and management of refractory cases are warranted.     

Parasites of domestic and wild animals in South Africa. XXV. Ixodid ticks on sheep in the north-eastern Orange Free State and in the eastern Cape Province

The tick burdens of 115 Merino sheep, slaughtered over a period of 15 consecutive months on a farm in the north-eastern Orange Free State, were determined. A total of 7 ixodid and 1 argasid tick species were recovered and the seasonal abundances of Boophilus decoloratus, Hyalomma marginatum rufipes, Margaropus winthemi and Rhipicephalus evertsi evertsi were determined. One hundred and forty-nine Merino sheep were slaughtered over periods varying from 10 to 25 months on 3 farms in Eastern Province Thornveld in the eastern Cape Province and their tick burdens determined. Fourteen ixodid tick species were recovered from these animals and the seasonal abundances of Amblyomma marmoreum, B. decoloratus, Haemaphysalis silacea, R. evertsi evertsi and Rhipicephalus nitens were ascertained. On a farm in Valley Bushveld in the eastern Cape Province, 2 Dorper sheep were slaughtered each month for a period of 24 consecutive months. These 48 sheep harboured 10 ixodid tick species and the seasonal abundances of A. marmoreum, H. silacea, Rhipicephalus appendiculatus and Rhipicephalus glabroscutatum were determined. A total of 17 ixodid tick species, of which 12 had reached the adult stage, where recovered from the sheep on the 5 farms.     

Tick-borne blood parasites in nyala (Tragelaphus angasii, Gray 1849) from KwaZulu-Natal, South Africa

A total of 97 blood samples of nyala (Tragelaphus angasii, Gray 1849) from South Africa were tested for the presence of tick-borne haemoparasites by means of polymerase chain reaction (PCR) and reverse line blot (RLB) hybridization. The majority of blood samples contained several different haemoparasites, often in combination. Prevalent haemoparasites were Theileria sp. (kudu), T. buffeli, Theileria sp. (sable), T. bicornis, Ehrlichia sp. Omatjenne, Anaplasma marginale and A. bovis. This serves as the first report of Theileria sp. (kudu), T. buffeli, T. bicornis, Ehrlichia sp. Omatjenne, A. marginale and A. bovis in nyala, who seem to carry multiple haemoparasites without ill effect.     

Diseases of free-ranging chickens in the Qwa-Qwa District of the northeastern Free State province of South Africa

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 preliminary survey of viruses in pasture grasses in South Africa

Little work has been done in South Africa on the incidence of viruses in pasture grasses. The aim of this work was to carry out a survey of virus infections of some of the economically‐important pasture grasses in South Africa. Twelve winter and summer pasture grass species and one cereal forage crop species were collected from six different regions in early, mid‐ and late winter and summer. Plants were tested for virus(es) by means of symptomatology, transmission, dot‐blot immunoassays, Ouchterlony tests and electron microscopy. Serological tests indicate that Avena sativa from Roodeplaat and Bromus unioloides from Potchefstroom, Cedara and Nooitgedacht are positive for maize dwarf mosaic virus (MDMV). Lolium multiflorum from Cedara appears to be infected with two viruses, brome mosaic virus (BMV) and a potyvirus‐like agent, possibly ryegrass mosaic virus (RMV).     

Larval biology of rhipicephalus (Boophilus) decoloratus (Acarina: Ixodidae) in Free State Province, South Africa

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.     

Diversity,seasonality and sites of attachment of adult ixodid ticks on dogs in the central region of the Free State Province,South Africa

Several surveys of ticks infesting dogs belonging to owners in resource-limited and more affluent communities have been conducted in South Africa, but no such investigation has been carried out in the Free State Province of this country. The present study was initiated to meet this shortcoming. Ticks were collected from dogs at six localities in, and to the east of the city of Bloemfontein in the central region of the province. Three of these localities could be classed as resource-limited and two as affluent, while the sixth locality was an animal shelter serving all members of the public. Adult ticks belonging to nine ixodid tick species were collected, of which Rhipicephalus sanguineus was the most numerous. Significantly more R. sanguineus was collected from dogs at resource-limited than at more affluent localities. The greatest proportions of these ticks attached to the backs and necks of the dogs, with the proportions being larger in long-haired than in short-haired dogs. Most R. sanguineus were collected during the warmer months particularly from January to April. The greatest proportions of Haemaphysalis leachi, the next most numerous species, were also collected from the backs and the necks of the dogs. Most of these were present during the period September to November.     

Nematode parasites of Clarias gariepinus (Burchell, 1822) from the Rietvlei Dam, South Africa

Catfish, Clarias gariepinus, from the Rietvlei Dam near Pretoria, South Africa were examined for nematode parasites. Two species, Procamallanus laeviconchus in the stomach and Contracaecum spp. larvae in the abdominal cavity, were found. The morphology of these species, based on light and scanning electron microscopy, and how they compare with previously described specimens are discussed. Infection rates were mild compared to previous surveys although Contracaecum spp. had a high prevalence of 86%.     

A serological survey of antibodies to Leptospira species in dogs in South Africa

Leptospirosis, a disease more common in the tropics, can cause a life-threatening multisystemic syndrome in humans and animals. Immunity, whether natural or vaccine-induced, is serogroup-specific with the infecting serovars varying according to geographical locality. In South Africa, in spite of the fact that the bacterin vaccine for some Leptospira serovars is often used, there is no recent information on the incidence of canine leptospirosis as well as the infecting serovar/s. The aim of this study, which was undertaken on sera collected in 2008 and 2009 from both strays and owned dogs predominantly in the coastal regions of South Africa, was to determine the presence of leptospiral antibodies to 15 serovars known to infect dogs. Of the 530 samples tested, 25 tested positive to 7 different serovars with the microscopic agglutination test (MAT). Nine of the 25 samples tested positive to more than one serovar. The 2 serovars most frequently represented were Canicola, which reacted to 17 sera, and Pyrogenes, which reacted to 10 sera. Currently the only vaccines available in South Africa in different combinations contain serovars Canicola, Icterohaemorrhagiae, Pomona and Grippotyphosa. The results showed that the use of vaccines containing serovar Canicola is still justifiable in certain regions of the country. However, the presence of antibodies to serovar Pyrogenes in several dogs, pending a broader investigation, indicates that this serovar should also be included in the range of Leptospira vaccines for use in South Africa.     

Arthropod parasites of Hartmann's mountain zebra, Equus zebra hartmannae, in South West Africa/Namibia

Twelve Hartmann's mountain zebra, Equus zebra hartmannae, were shot for arthropod parasite recovery during the period June 1980-June 1981 on a farm in the Khomas Hochland region of South West Africa/Namibia. Four species of Gasterophilus larvae, 1 species of Rhinoestrus larvae and 3 ixodid tick species were recovered. The seasonal prevalence of the Gasterophilus species larvae and of Rhipicephalus evertsi mimeticus was determined. Three horses examined on the same farm were infested with larvae of 2 Gasterophilus species and with the same ixodid tick species as the zebras.     

Temporal and spatial dynamics of mineral levels of forage,soil and cattle blood serum in two semi-arid savannas of South Africa

In this study, we examined temporal and spatial dynamics of minerals of forage, soil and cattle serum in two savannas (valley and plain) of South Africa. The aims were to explore the relationships between ecosystem components, and plan communal grazing and fodder flow for sustainable livestock production. In each area, grazing sites near, at intermediate distance from (middle) and far from homesteads were selected. In the valley land, site interacted with season to influence local variations (P<0.05) of soil calcium and microelements. In the plain lands, local variations occurred for soil phosphorus and magnesium. At the large scale, most macro-minerals showed differences between the valley and plain lands. In the valley areas, forage calcium differed (P<0.05) locally in the dry season, whereas in the plain areas, potassium and phosphorus showed local variations (P<0.05) in the wet season. Seasonal variations of most forage elements were significant within each local site of both study areas. All forages were deficient in phosphorus and copper. Cattle serum from the valley area had low iron concentrations. The study concluded that biotic and abiotic factors may influence the distribution of soil and forage elements, but their effects may vary between the two areas. Rangeland improvement and supplementation strategies are suggested to sustain animal production.     

Prevalence of blood parasites among cattle at the central area of Saudi Arabia

The present study aimed to investigate the parasites infecting cattle blood at Al-Qassim region. Examination of 307 blood samples revealed that 235 (76.5%) and 3 (0.98%) of cattle were infected with Theileria annulata and Anaplasma marginale, respectively. T. annulata was the prevalent blood parasite among cattle while A. marginale was scarcely encountered. The monthly incidence of T. annulata ranged from 38.5% in March to 94.7% in October. Also, the infection rate reached a maximum (84.3%) in both autumn and summer seasons, while it decreased to reach (59.4%) in spring. It has been found that there was no difference between the infection rate of the laboratory and the abattoir collected samples. However, the intensity of infection was different between the two groups.     

A survey of free-living ixodid ticks on a commercial game farm in the Thabazimbi District, Limpopo Province, South Africa

Free-living stages of ticks on a commercial game farm in the Thabazimbi District, Limpopo Province, South Africa, were collected by drag-sampling with flannel strips during the period September 2003 to August 2004. A total of 5 tick species was collected from 4 sites. Boophilus decoloratus was the most abundant species, followed by Amblyomma hebraeum. Seasonal abundance of the ticks was quantified and an optimum time to implement control measures against the ticks is proposed.     

Relative resistance of six cattle breeds to the tick Boophilus decoloratus in South Africa

Adult females of the tick Boophilus decoloratus were removed from 6 breeds of cattle on 2 farms in the Northern Transvaal. Highest numbers of female ticks were collected from Simmentaler, followed by Santa Gertrudis, Bonsmara, Afrikaner, Brahman and Nguni. Resistance levels of each breed to B. decoloratus was positively correlated with the amount of Bos indicus genes in the breed, with the exception of Nguni, which is a sanga type but not pure B. indicus.