bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of fluorescence polarization immuno-assay in the diagnosis of plant-induced cardiac glycoside poisoning livestock in South Africa
Authors: Schultz R.A. , Kellerman T.S. , Van den Berg H.
Published: August 2012

Poisoning with cardiac glycoside-containing plants is collectively the most important plant-associated poisoning of livestock in southern Africa. As a diagnosis of this significant poisoning is currently based on circumstantial evidence, a practical chemical procedure indicating the presence of cardiac glycosides in plants and animal specimens would be of considerable benefit. The fluorescence polarization immunoassay (FPIA) method, used to determine digoxin plasma levels in humans and dogs, was adapted to estimate cardiac glycoside levels in known cardiac-glycoside- containing plants as well as in the rumen and organs of dosed sheep. Positive FPIA values were obtained with bufadienolide-containing plants, while negative results were obtained with plants not known to contain cardiac glycosides. The FPIA has aided in the diagnosis of cardiac glycoside poisoning in livestock and game in 30 outbreaks examined at the Division of Toxicology, Onderstepoort Veterinary Institute. Each outbreak is briefly described. As a result of this assay, a better understanding of cardiac glycoside poisoning has been reached.
First report of an outbreak of the oriental eye-fluke, Philophthalmus gralli (Mathis & Leger 1910), in commercially reared ostriches (Struthio camelus) in Zimbabwe
Authors: Mukaratirwa S. , Hove Thokozani , Cindzi Z.M. , Maononga D.B. , Taruvinga M. , Matenga Elizabeth
Published: August 2012

A total of 17 commercially reared ostriches (Struthio camelus) from Msengi farm, Chinhoyi, Zimbabwe, observed with swollen eyes, severe conjunctivitis and constant lacrimation accompanied by a purulent exudate, were restrained for further clinical examination. Some of the birds were semi-blind with severe loss of body condition. When examined, tiny organisms were observed attached to the nictitating membranes and the conjuctival sacs of both eyes. The organisms were identified as Philophthalmus gralli, the "oriental eye-fluke" and Melanoides tuberculata, a prosobranch snail, was confirmed as the intermediate host through natural and experimental infection. To the best of our knowledge this is the first record of the oriental eye-fluke infection in birds in Zimbabwe and Africa and extends its known geographical range.
Some observations on ticks (Acari : Ixodidae) infesting sheep in River Nile Province of Northern Sudan
Authors: Ahmed B.M. , El Hussein A.M. , El Khider A.O.
Published: August 2012

Five species of ixodid ticks were found in a cross-sectional survey in which 200 sheep were examined for ticks in River Nile Province, Sudan. Hyalomma anatolicum anatolicum was the predominant species (73.6 %), whereas ticks belonging to the Rhipicephalus sanguineus group (14.7 %), Rhipicephalus evertsi evertsi (9.1 %), Rhipicephalus simus (2 %) and Hyalomma dromedarii (0.5 %) were also found. The mean tick load was 11.2 per animal. In a subsequent longitudinal survey ticks were collected on a monthly basis from eight sentinel sheep that were introduced into the area. It was found that H. a. anatolicum almost disappeared during the hot period between April and August, whereas it's highest numbers were present in winter between November and February. It is concluded that there is only one generation of H. a. anatolicum per year, which may explain the yearround appearance of clinical cases of malignant ovine theileriosis indicating endemic instability of this disease in River Nile Province.
Immunization of young chicks using graded dose of wild strain of Eimeria tenella
Authors: Kimbita E.N. , Samani P.M. , Machange E.N. , Silayo R.S.
Published: August 2012

A wild strain of Eimeria tenella was isolated and utilized for immunization studies. Its optimal sporulation was attained at room temperature 24-25 °C after 24-48 h. Two groups of chicks were immunized by dosing a graded dose of five oocysts/chick/day for 6 days followed by 50 oocysts/chick/day for 7 days. A third group was not immunized and served as a negative control. Immunized chicks gained mass at the same rate as unimmunized ones, but when challenged with 200 000 oocysts/chick, mass gains declined in the unimmunized group. The growth rate of immunized chicks was not affected by challenge (P > 0.05). Upon challenge, unimmunized chicks produced significantly more oocysts than immunized chicks (P < 0.005). Immunized chicks withstood a challenged with 200 000 oocysts/chick without developing any clinical signs whereas the unimmunized chicks developed typical clinical signs of coccidiosis. Unimmunized chicks had significantly more severe lesions in the caecum than any other group (P > 0.005) and also produced significantly more oocysts than any other group (P > 0.005).
Electrocardiographic surrogates of structural myocardial alterations in the Dorper sheep heart
Authors: Ker J. , Webb E.C.
Published: August 2012

In this study we evaluated the validity of well-known human electrocardiographic markers of myocardial pathology in Dorper sheep. These markers include: the duration of the QRS complex of premature ventricular complexes (PVCs), the presence of notching of the QRS complex of PVCs and change of the ST-segment of PVCs. It was shown that these three electrocardiographic phenomena correlate with myocardial pathology in the hearts of Dorper sheep. We also describe a new electrocardiographic indicator of myocardial pathology, namely an increase in the frequency of cardiac memory T waves as a new electrocardiographic surrogate for myocardial pathology in the hearts of Dorper sheep.
Association of trypanosomosis risk with dairy cattle production in western Kenya
Authors: Mugunieri G.L. , Matete G.O.
Published: August 2012

Dairy cattle reared in western Kenya are exposed to medium to high levels of trypanosomosis risk. The social background, farm characteristics and dairy cattle productivity of 90 and 30 randomly selected farmers from medium- and high-risk trypanosomosis areas, respectively, were compared. All the 120 farmers were visited between July and August 2002. Data analysis was performed using descriptive statistics and analysis of variance. The results showed that increased trypanosomosis risk represented by an increase in disease prevalence in cattle of 1% to 20 % decreased the density of dairy cattle by 53 % and increased the calving interval from 14 to 25 months. The increased risk was also associated with a significant increase in cattle mortalities and in a lactation period of 257 to 300 days. It was concluded that removal of the trypanosomosis constraint on dairy production would lead to expansion of dairying since the domestic demand for dairy products is expected to increase.
Discrimination between sheep-associated and wildebeest-associated malignant catarrhal fever virus by means of a single-tube duplex nested PCR
Authors: Bremer C.W. , Swart H. , Doboro F.A. , Dungu B. , Romito M. , Viljoen G.J.
Published: August 2012

A single-tube duplex nested polymerase chain reaction (sdn-PCR) was developed for the detection of and discrimination between ovine herpesvirus-2 (OvHV-2) and alcelaphine herpesvirus-1 (AlHV-1). These viruses respectively cause sheep- and wildebeest-associated malignant catarrhal fever (SAMCF and WA-MCF). In the first step of the sdn-PCR, two primers with high annealing temperatures based on conserved regions of the tegument genes were used for DNA amplification. In the second step, two primer sets based on variable regions of the respective OvHV-2 and AlHV-1 genes and with annealing temperatures > 11 °C below the primers used in the first step, were used. Internal regions of different sizes from amplicons produced in the first step were amplified. This single-tube test obviates the need for two separate assays to detect both viral types, thereby reducing time, labour and cost.
Natural infection rates and transmission of Theileria annulata by Hyalomma anatolicum anatolicum ticks in the Sudan
Authors: Salih D.A. , Sharieff O.E. , Lazarus A.G. , Hassan S.M. , El Hussein A.M.
Published: August 2012

Hyalomma anatolicum anatolicum nymphs were collected from two localities in the Sudan: Eddamer in Northern Sudan and Wad-Medani in Central Sudan. They were allowed to moult to adult ticks, which were assessed for Theileria infection in their salivary glands using Feulgen stain. At Eddamer, 49.6 % of 123 ticks examined were infected with Theileria and the mean intensity of infection was 1.3 (i.e. the number of infected acini / number of infected ticks). At Wad-Medani, 8.6 % of 162 ticks were infected and the mean intensity of infection was 7.9. The prevalence of infection was higher in female than in male ticks at both localities. When adult H. a. anatolicum were applied onto two susceptible calves, both animals developed the severe form of theileriosis.
The genus Hyalomma Koch, 1844. I. Reinstatement of Hyalomma (Euhyalomma) glabrum Delpy, 1949 (Acari, Ixodidae) as a valid species with a redescription of the adults, the first description of its immature stages and notes on its biology
Authors: Apanaskevich D.A. , Horak I.G.
Published: August 2012

For nearly 50 years the ixodid tick Hyalomma marginatum turanicum, reputedly introduced into South Africa on imported Persian sheep, has been considered identical to the Asian Hyalomma (Euhyalomma) marginatum turanicum Pomerantzev, 1946. Comparisons of this tick with the Asian H. (E.) m. turanicum and other subspecies of Hyalomma (Euhyalomma) marginatum, however, reveal that it is an old taxon, namely Hyalomma rufipes glabrum Delpy, 1949. It is hereby reinstated as Hyalomma (Euhyalomma) glabrum, and its adults are redescribed and its immature stages described for the first time. The preferred hosts of its adults are large herbivores such as zebras, gems bok and eland, on which it occurs during summer. The preferred hosts of its immature stages are scrub hares and ground-frequenting birds, on which it is present during autumn and winter. Data on its distribution and possible disease relationships are also provided.
Hosts, seasonality and geographic distribution of the South African tortoise tick, Amblyomma marmoreum
Authors: Horak I.G. , McKay I.J. , Heyne Heloise , Spickett A.M.
Published: August 2012

The tortoise tick Amblyomma marmoreum was collected from large numbers of reptiles and other animals during the course of numerous surveys conducted in South Africa. A total of 1 229 ticks, of which 550 were adults, were recovered from 309 reptiles belonging to 13 species, with leopard tortoises, Geochelone pardalis being the most heavily infested. The 269 birds sampled harboured 4 901 larvae, 217 nymphs and no adult ticks, and the prevalence of infestation was greatest on hel meted guinea fowls, Numida meleagris. Only two larvae were recovered from 610 rodents, including 31 spring hares, Pedetes capensis, whereas 1 144 other small mammals yielded 1 835 immature ticks, of which 1 655 were collected from 623 scrub hares, Lepus saxatilis. The 213 carnivores examined harboured 2 459 ticks of which none were adult. A single adult tick and 6 684 larvae and 62 nymphs were recovered from 656 large herbivores, and a total of 4 081 immature ticks and three adults were collected from 1 543 domestic animals and 194 humans. Adult male and female A. marmoreum were most numerous on reptiles during January and February, and larvae during March. The largest numbers of larvae were present on domestic cattle and helmeted guineafowls in the Eastern Cape Province during March or April respectively, whereas larvae were most numerous on helmeted guineafowls, scrub hares and the vegetation in north-eastern Mpumalanga Province during May. In both provinces nymphs were most numerous between October and December. Amblyomma marmoreum appears to be most prevalent in the western regions of the Western and Eastern Cape and Free State provinces, and the north-eastern regions of the Northern Cape, KwaZulu- Natal, Mpumulanga and Limpopo provinces.
Prevalence of common gastrointestinal nematode parasites in scavenging pigs of different ages and sexes in Eastern Centre province, Burkina Faso
Authors: Tamboura H.H. , Banga-Mboko H. , Maes D. , Youssao I. , Traore A. , Bayala B. , Dembele M.A.
Published: August 2012

The range and infestation intensities of gastrointestinal parasitic nematode species depend on the type of swine production system. The present study focused mainly on nematodes of veterinary importance in scavenging pigs in Burkina Faso, and aimed at determining the prevalence of gastro-intestinal nematode parasites by means of faecal egg per gram (EPG) counts. Between November 2001 and October 2002, faecal samples from 383 pigs of different sexes and ages (< 5 months, 5-12 months and > 12 months) were collected from the rectum and examined for gastrointestinal nematodes parasites using the Mc Master method. Of the 383 pigs examined, 91 % were infected by one or more para sites. Ascaris suum (40 %; 100-1 400 EPG) was the most prevalent parasite followed by Strongyloides ransomi (21 %; 100-4 200 EPG), Oesophagostomum spp. (18 %; 100-1 000 EPG), Hyostrongylus rubidus (11 %; 100-1 800 EPG), Globocephalus spp. 10 %; 100-400 EPG) and Trichuris suis (1 %; 100-200 EPG). The prevalence was significantly higher in female pigs (n = 239) than in males. In addition, females excreted significantly (P < 0.05) more eggs in their faeces than males, except in the case of Globocephalus spp. The age of the animal had no effect on the prevalence of A. suum whereas there were significant differences in age categories concerning S. ransomi, H. rubidus, Oesophagostumum spp. and Globocephalus spp. Unexpectedly, the high prevalence of these common parasites was not accompanied by elevated EPG values, which suggests the existence of moderate infestations. The present work indicates that the common nematode infestations in pigs do not necessarily need a systematic herd anthelmintic treatment, as only a small number of worms is required to induce immunity. A further study is needed to formulate appropriate and cost-effective strategies for the control of gastro-intestinal nematode parasites in pigs in Burkina Faso.
Faecal helminth egg and oocyst counts of a small population of African lions (Panthera leo) in the southwestern Kalahari, Namibia : research communication
Authors: Smith Y. , Kok O.B.
Published: August 2012

An endoparasite survey of a small pride of African lions (Panthera leo) was conducted at Intu Afrika Kalahari Game Reserve, southwestern Namibia, during winter and summer of 2003 and 2004, respectively. Overall, 23 fresh lion scats were collected opportunistically during fieldwork trials. A flotation technique was employed for the diagnosis of parasites. Three nematodes, Ancylostoma braziliense, Gnathostoma spinigerum and Uncinaria stenocephala and two coccidians, Toxoplasma gondii and Isospora felis were recorded. By using the McMaster method for quantification, a maximum number of 14 866 oocysts per gram of faeces was obtained for I. felis during winter 2003. Endoparasite taxa carried by the different individuals in the pride were found to be related to their levels of association. Rates of infection were relatively low as a result of the habitat, semi-captive conditions and earlier sporadic deworming.
An update of the bovine trypanosomosis situation at the edge of Hluhluwe-iMfolozi Park, KwaZulu-Natal Province, South Africa : research communication
Authors: Van den Bossche P. , Esterhuizen J. , Nkuna R. , Matjila T. , Penzhorn B. , Geerts S. , Marcotty T.
Published: August 2012

To obtain updated data on and assess the contribution of trypanosomosis to the disease burden of cattle kept at the edge of the Hluhluwe-iMfolozi Park, a survey was conducted at Mvutshini Dip. Use was made of a purposeful sampling strategy by restricting sampling to animals that the livestock owner considered to be in poor condition. Of a total of 76 blood samples collected, 26 were parasitologically positive and 46 were positive on PCR / RFLP. Almost all infections were due to Trypanosoma congolense savannah subgroup. A total of 63 animals had a PCV < 24 % and were considered to be anaemic. Results from the survey show that trypanosome infections contribute significantly to the overall burden of disease in the area. Further research is required to develop appropriate control methods.
Observations on mass production of Calicophoron microbothrium metacercariae from experimentally and naturally infected Bulinus tropicus
Authors: Mavenyengwa M. , Mukaratirwa S. , Obwolo M. , Monrad J.
Published: August 2012

In an attempt to establish an ideal method for mass production of Calicophoron microbothrium metacercariae, a study was carried out to compare the shedding capacities of Bulinus tropicus naturally and experimentally infected with C. microbothrium. A total of 906 F1 B. tropicus between 4 and 5 weeks old were each experimentally infected with two C. microbothrium miracidia and monitored for 12 weeks. The infected snails were fed on dried lettuce and fish flakes and were kept in 1 l plastic aquaria housed in a snail room where temperature, light and humidity were controlled. Seventy-four percent of the experimentally infected snails died during the prepatent period and of the remaining, only 13.2 % developed patent infection, while 12.5 % were refractory. Snail growth rate was poor and the average shedding rate was 20 cercariae per snail per day. Compared to the experimentally infected snails, 2 200 adult B. tropicus, collected from the field and naturally infected with C. microbothrium, yielded high numbers of metacercariae. Eighty-four percent of the snails died within 7 weeks of the study with peak mortality occurring from the 2nd to the 4th week of infection and coinciding with an overall decrease in the number of cercariae shed.
Gastric nematodes of Nile crocodiles, Crocodylus niloticus Laurenti, 1768, in the Okavango River, Botswana
Authors: Junker K. , Wallace K. , Leslie A.J. , Boomker J.
Published: August 2012

The ascaridoid nematodes Dujardinascaris madagascariensis Chabaud & Caballero, 1966, Dujardinascaris dujardini (Travassos, 1920), Gedoelstascaris vandenbrandeni (Baylis, 1929) Sprent, 1978 and Multicaecum agile (Wedl, 1861) Baylis, 1923 were recovered from the stomach contents of Crocodylus niloticus Laurenti, 1768 from the Okavango River, Botswana, together with Eustrongylides sp., a dioctophymatoid nematode usually parasitizing piscivorous birds. Dujardinascaris madagascariensis was present in most of the infected hosts, while the remaining species were mostly represented in single collections in one to three hosts. All four ascaridoid nematodes represent new geographic records.
Treatment of natural ovine malignant theileriosis with a chloroform extract of the plant Peganum harmala : research communication
Authors: Mirzaiedehaghi M.
Published: August 2012

One hundred sheep naturally infected with Theileria lestoquardi were treated with a chloroform extract of the plant Peganum harmala. The treatment was continued for 5 days, the dose of extract being 5 mg/kg per day. Sixty-five of the sheep responded to treatment and recovered but 35 did not and died. The cure rate was 65 %
Epidemiological studies of Schistosoma mattheei infections in cattle in the highveld and lowveld communal grazing areas of Zimbabwe
Authors: Pfukenyi D.M. , Mukaratirwa S. , Willingham A.L. , Monrad J.
Published: August 2012

During the period between January 1999 and December 2000, the distribution and seasonal patterns of Schistosoma mattheei infections in cattle in the highveld and lowveld communal grazing areas of Zimbabwe were determined through monthly coprological examination. Faecal samples of cattle were collected from 12 and nine dipping sites in the highveld and lowveld communal grazing areas, respectively. Patterns of distribution and seasonal fluctuations of the intermediate host-snail populations and the climatic factors influencing the distribution were also determined at monthly intervals from November 1998 to October 2000, a period of 24 months, in six dams and six streams in the highveld and nine dams in the lowveld communal grazing areas. Monthly, each site was sampled for relative snail density, the vegetation cover and type, and physical and chemical properties of the water. Mean monthly rainfall and temperature were recorded. Snails collected at the same time were individually examined for shedding of cercariae of S. mattheei and Schistosoma haematobium. A total of 16 264 (5 418 calves, 5 461 weaners and 5 385 adults) faecal samples were collected during the entire period of study and 734 (4.5 %) were positive for S. mattheei eggs. Significantly higher prevalences were found in the highveld compared to the lowveld (P < 0.001), calves compared to adult cattle (P < 0.01) and the wet season compared to the dry season (P < 0.01). Faecal egg output peaked from October/ November to March / April for both years of the study. Bulinus globosus, the snail intermediate host of S. mattheei was recorded from the study sites with the highveld having a significantly higher abundance of the snails than the lowveld (P < 0.01). Monthly densities of B. globosus did not show a clearcut pattern although there were peaks between March / May and September / November. The mean num ber of snails collected was positively correlated with the water plants Nymphaea caerulea and Typha species. Overall, 2.5 % of B. globosus were shedding Schistosoma cercariae. In the highveld, 2.8 % of B. globosus were infected with schistosome cercariae and 1.5 % in the lowveld, with the figures at individual sites ranging from 0-18.8 % in the highveld and from 0-4.5 % in the lowveld. The cercariae recorded here were a mixture of S. mattheei and S. haematobium since they share the same intermediate host. The transmission of Schistosoma cercariae exhibited a marked seasonal pattern, being more intensive during the hot, dry season (September / November).
Ultrastructural features of the follicular wall in developing follicles of the sexually immature ostrich (Struthio camelus)
Authors: Madekurozwa M-C. , Kimaro W.H.
Published: August 2012

The ultrastructure of the follicular wall in primordial, previtellogenic and vitellogenic follicles of the sexually immature ostrich is described in the present study. The follicular wall consists of a zona radiata, granulosa cell layer, basal lamina and thecal layer. Cytoplasmic processes from the plasma membranes of the granulosa cell layer and the ovocyte form the zona radiata in previtellogenic and vitellogenic follicles. The granulosa cell layer transforms from simple cuboidal epithelium in primordial follicles to simple columnar or pseudostratified columnar epithelium in previtellogenic and vitellogenic follicles. Transosomes were observed along the apical and lateral plasma membranes of granulosa cells. The thecal layer in previtellogenic and vitellogenic follicles consists of interna and externa components. The fibroblasts in the theca externa contain microfilaments, which are thought to be actin filaments. The study revealed ultrastructural features, which are associated with the transportation of yolk precursors and nutrients into the ovoplasm. In addition, the study indicates that, although the cells in the theca externa contain microfilaments, they do not possess the ultrastructural characteristics of smooth muscle cells.
Infectivity of Theileria parva sporozoites following cryopreservation in four suspension media and multiple refreezing : evaluation by in vitro titration
Authors: Mbao V. , Berkvens D. , Dolan T. , Speybroeck N. , Brandt J. , Dorny P. , Van den Bossche P. , Marcotty T.
Published: August 2012

Theileria parva sporozoite stabilates are used for immunizing cattle against East Coast fever and in in vitro sporozoite neutralization assays. In this study, we attempted to identify a cheaper freezing medium and quantified the infectivity loss of sporozoites due to refreezing of stabilates, using an in vitro technique. Pools of stabilates prepared using Minimum Essential Medium (MEM), Roswell Park Memorial Institute (RPMI 1640), foetal calf serum (FCS) and phosphate-buffered saline (PBS) were compared. All were supplemented with bovine serum albumin except the FCS. RPMI 1640 was as effective as MEM in maintaining sporozoite infectivity while the infectivity in PBS and FCS reached only 59 % and 67 %, respectively. In a second experiment, a stabilate based on MEM was subjected to several freeze-thaw cycles including various holding times on ice between thawing and refreezing. Refrozen stabilate gave an average sporozoite infectivity loss of 35 % per cycle. The results indicate that RPMI can be used as a cheaper freezing medium for T. parva stabilates and that refrozen stabilate doses need to be adjusted for the 35 % loss of infectivity.
Seasonal infertility in Kenyan pig breeding units : research communication
Authors: Boma M.H. , Bilkei G.
Published: August 2012

Reproductive performance of 12 Kenyan pig breeding units (56-299 sows per unit) of similar feeding, genetics and health status were evaluated from October 2003 to October 2004 during hot and cooler periods. Sows during cooler months of the year (April to October, average temperature between 08:00 and 17:00: 25.2 + 2.2 °C) had shorter (P < 0.01) weaning to service intervals (7.9 + 2.2 days vs 12.7 + 2.7 days, respectively), less (P < 0.01) regular returns to service (5.7 + 1.9 % vs 9.9 + 1.9 %, respectively), higher (P < 0.01) farrowing rates (80.1 + 4.4 % vs 70.8 + 3.8 %, respectively), and larger born (10.0 + 1.1 vs 9.1 + 1.7, P < 0.05) and weaned litter sizes (9.2 + 1.2 vs 8.0 + 1.3, P < 0.05) compared with the time periods of high ambient temperature (November to March, between 08:00 and 17:00: 37.2 + 3.3 °C). It was concluded that a high ambient temperature is a risk factor for reproductive performance in pig breeding units.
Ticks (Acari: Ixodidae) of small antelopes : steenbok, Raphicerus campestris and suni, Neotragus moschatus : research communication
Authors: Golezardy H. , Horak I.G.
Published: August 2012

During surveys on the tick burdens of various wildlife species in South Africa, nine small antelopes became available for study. Six of these were steenbok, Raphicerus campestris and three sunis, Neotragus moschatus, and their tick burdens are recorded here. The steenbok were examined in three nature reserves and harboured nine tick species. The sunis were examined in a fourth reserve and were infested with eight species. The steenbok and sunis were generally infested with the immature stages of the same tick species that infest larger animals in the same geographic regions. In addition the sunis harboured Haemaphysalis parmata, which in South Africa is present only in the eastern and north-eastern coastal and adjacent areas of KwaZulu-Natal Province. They were also infested with Rhipicephalus kochi, which in South Africa occurs only in the far north-east of the KwaZulu-Natal and Limpopo Provinces.
Captive breeding of the white rhinoceros, Ceratotherium simum, and the Cape buffalo, Syncerus caffer : research communication
Authors: Skinner J.D. , Dott H.M. , Matthee A. , Hunt L.
Published: August 2012

Breeding records of 40 white rhinoceros and 155 Cape buffalo were analysed. Three rhinoceros cows bred in captivity, themselves conceived for the first time at 84, 87 and 95 months of age, respectively. Rhinoceros cows breed throughout the year. There is no evidence of a relationship between calving interval and month of birth. Calving intervals were normally distributed about the mean of 34 months and there were no significant differences between bulls, cows or sex of calf. There was no difference in the sex ratio of calves born to young cows nor older cows. The male:female ratio of the calves was Younger cows did not have shorter birth intervals. Although captive Cape buffaloes breed throughout the year, there is a preponderance of births in midsummer. There was some evidence that larger cows produce heavier calves and that season of birth may influence birth weight. Male calves weighed 41.20 + 0.68 kg vs 39.00 + 0.73 kg (range 24-60 kg) for female calves but this difference was not significant. Calving intervals were normally distributed about the mean of 395 days and the male:female ratio of the calves was 1:1.2.
Occurrence of multiple drug resistance in Trypanosoma brucei rhodesiense isolated from sleeping sickness patients
Authors: Maina N. , Kagira J.M.
Published: August 2012

The occurrence of cross-resistance among melarsoprol-resistant Trypanosoma brucei rhodesiense isolates was investigated in this study. The isolates, T. b. rhodesiense KETRI 237, 2538, 1992, 2709, 2694 and 3530, had been obtained from sleeping sickness patients in Kenya and Uganda between 1960 and 1985. Five groups consisting of six mice each were inoculated intraperitoneally with 105 parasites of each isolate, and 24 h later treated with either melarsoprol, homidium chloride, diminazene aceturate or isometamidium chloride. The control group comprised infected but untreated mice. The mice were monitored for cure for a period of 60 days post-treatment. The mean prepatent period in the control mice was 5 days while the mean survival period was 22 days. Five of the stabilates, KETRI 237, 2538, 2709, 2694, and 3530, were confirmed to be melarsoprol resistant. Cross-resistance was observed, with the majority of the isolates being resistant to homidium chloride (5/6) and diminazene aceturate (5/6), but all were sensitive to isometamidium chloride (6/6). However T. b. rhodesiense KETRI 1992, which was previously considered as melarsoprol resistant, was sensitive to all the drugs tested. In conclusion, our study has revealed the existence of cross-resistance among the melarsoprol resistant isolates which could only be cured by isometamidium.
Prevalence and determinants of Cryptosporidium spp. infection in smallholder dairy cattle in Iringa and Tanga Regions of Tanzania
Authors: Swai E.S. , French N.P. , Karimuribo E.D. , Fitzpatrick J.L. , Bryant M.J. , Kambarage D.M. , Ogden N.H.
Published: August 2012

The prevalence of Cryptosporidium spp. infection in a cross-sectional study of dairy cattle, from two contrasting dairying regions in Tanzania, were determined by staining smears of faecal samples with the modified Ziehl-Neelsen technique. Of the 1 126 faecal samples screened, 19.7% were positive for Cryptosporidium spp. The prevalence was lower in Tanga Region than in Iringa Region. The prevalence of affected farms was 20% in Tanga and 21% in Iringa. In both regions, the probability of detecting Cryptosporidium oocysts in faeces varied with animal class, but these were not consistent in both regions. In Tanga Region, Cryptosporidium oocysts were significantly more likely to be found in the faeces of milking cows. In Iringa Region, the likelihood that cattle had Cryptosporidium-positive faeces declined with age, and milking cattle were significantly less likely to have Cryptosporidium positive faeces. In this region, 7% of cattle were housed within the family house at night, and this was marginally associated with a higher likelihood that animals had Cryptosporidium-positive faeces. Our study suggests that even though herd sizes are small, Cryptosporidium spp. are endemic on many Tanzanian smallholder dairy farms. These protozoa may impact on animal health and production, but also on human health, given the close associations between the cattle and their keepers. Further studies are required to assess these risks in more detail, and understand the epidemiology of Cryptosporidium spp. in this management system.
The prevalence, organ distribution and fertility of cystic echinoccosis in feral pigs in tropical North Queensland, Australia
Authors: Lidetu D. , Hutchinson G.W.
Published: August 2012

An investigation was carried out to study the prevalence of Echinococcus granulosus hydatidosis in feral pigs (Sus domesticus) in the Charters Towers region of tropical North Queensland. Data were collected from a total of 238 carcasses, which were hunted and shot in the Burdekin River catchment area. Organs of the abdominal, thoracic, and pelvic cavities were examined for the presence of hydatid cysts. In the laboratory, cysts and hydatid cyst fluids were examined under a stereoscopic binoc ular microscope and a compound microscope. An overall prevalence of E. granulosus hydatid cysts in feral pigs was found to be 31.1%. There was no significant difference in either sex or age between infected and non-infected feral pigs. The predilection sites of cysts were livers (23%) and lungs (62%), with more cysts in lungs (252) than livers (48). The ratio of livers to lungs infected with fertile cysts was 1:4 compared to 1:8 sterile cysts. The overall fertility of cysts was 70.1%. The percentage of fertile cysts in liver and lung was 79.2% and 68.7%, respectively. The diameter of fertile cysts ranged from 15 to over 60 mm. There was no significant difference in size between fertile and non-fertile cysts in lungs. The high prevalence rate and fertility of cysts in feral pigs confirm that feral pigs can take part in the sylvatic cycle of the parasite in the region. The public health significance of this observation is potentially very important.
Comparative descriptions of the pupae of five species of the Culicoides imicola complex (Diptera, Ceratopogonidae) from South Africa
Authors: Nevill Hilda , Venter G.J. , Meiswinkel R. , Nevill E.M.
Published: August 2012

The viruses causing the economically important livestock diseases of African horse sickness (AHS) and bluetongue (BT) are transmitted by biting midges of the genus Culicoides (Diptera, Cerato po gonidae). In the Old World the most important vectors of these diseases are Culicoides imicola Kieffer, 1913, Culicoides brevitarsis Kieffer, 1917 and Culicoides bolitinos Meiswinkel, 1989. All three of these vectors belong to the Imicola complex of the subgenus Avaritia Fox, 1955. This species complex now comprises 12 sibling species; ten occur in sub-Saharan Africa and are difficult to identify (based mostly on subtle variations in the wing patterns) and so additional methods of reliable identification are needed. The pupal exuviae of the five commonest sibling species (C. imicola, C. bolitinos, Culicoides loxodontis Meiswinkel, 1992, Culicoides tuttifrutti Meiswinkel, Cornet & Dyce, 2003 and Culicoides sp. # 107) harvested from a variety of large herbivore dung types and from decaying fruits, are described and illustrated in detail. It is shown that they can be differentiated clearly on a number of morphological characters and, furthermore, are separable into two distinct groups based (principally) on the shape of the respiratory organ. A key for identifying and differentiating these five pupae is provided. Also, the pupa of the Oriental-Australasian C. brevitarsis was compared with its allopatric sister taxon, C. bolitinos. Because they share a common larval habitat (cattle and buffalo dung) and are almost inseparable in the adult phenotype, the question of their possible synonymy is raised. However, their respective pupae could not be differentiated on gross morphology and so it is argued that this unresolved problem requires a molecular solution.
Tetrameres numida n. sp. (Nematoda: Tetrameridae) from Helmeted guineafowls, Numida meleagris (Linnaeus, 1758), in South Africa
Authors: Boomker J. , Junker K.
Published: August 2012

Tetrameres numida n. sp. from the proventriculus of Helmeted guinea fowls, Numida meleagris, in South Africa is described from eight male and four female specimens. The new species shares some characteristics with other Tetrameres species, but can be differentiated by a unique combination of characters. It bears two rows of cuticular spines extending over the whole length of the body and possesses two spicules. The left spicule measures 1 699-2 304 ?m and the right one 106-170 mm. Caudal spines are arranged in three ventral and three lateral pairs and the tail is 257-297 mm long. Diagnostic criteria of some of the previously described species of the genus Tetrameres from Africa and other parts of the world have been compiled from the literature and are included here.
Redescription of Haemaphysalis (Rhipistoma) elliptica (Koch, 1844), an old taxon of the Haemaphysalis (Rhipistoma) leachi group from East and southern Africa, and of Haemaphysalis (Rhipistoma) leachi (Audouin, 1826) (Ixodida, Ixodidae
Authors: Apanaskevich D.A. , Horak I.G. , Camicas J-L.
Published: August 2012

Koch (1844) originally described only the male of Haemaphysalis (Rhipistoma) elliptica (Koch, 1844), which he named Rhipistoma ellipticum. For the past century, however, this name has been considered a junior synonym of Haemaphysalis (Rhipistoma) leachi (Audouin, 1826), or a nomen nudum. We redescribe here the male and larva of H. (R.) elliptica and describe the female and nymph for the first time. Our redescription is based on the male holotype, plus numerous specimens from southern and East Africa. The adults of this tick parasitize domestic and wild carnivores, and the immature stages infest rodents in these regions. For comparative purposes redescriptions of all parasitic stages of H. (R.) leachi are provided. It parasitizes the same hosts as H. (R.) elliptica in Egypt, and in northeastern, Central, West and East Africa.
Ultrastructural features of the uterus in the sexually immature ostrich (Struthio camelus) during periods of ovarian inactivity and activity
Authors: Madekurozwa M-C.
Published: August 2012

The ultrastructure of the surface epithelium and tubular glands of the uterus in the immature ostrich is described. In ostriches with inactive ovaries the uterus is lined by a non-ciliated simple columnar epithelium, with basally located heterochromatic nuclei. Scanning electron microscopy revealed that these non-ciliated cells have a dense microvillous cover. A simple columnar to pseudostratified columnar epithelium, comprised of non-ciliated and ciliated cells, lines the uterus in birds with active ovaries. The ciliated cells possess a wide luminal region, which contains a nucleus and various organelles. An accumulation of secretory granules was observed in the apical regions of the non-ciliated cells, as well as in a few ciliated cells. In addition to non-ciliated and ciliated cells, a cell type with rarefied cytoplasm was also identified. These cells appear to correspond to calcium secreting cells identified in other avian species. The results of this study indicate that, although uterine differentiation is present in immature ostriches with active ovaries, the production of secretory product appears to occur mainly in non-ciliated epithelial cells.
Age prevalence of trypanosomal infections in female Glossina morsitans morsitans (Diptera : Glossinidae) on the plateau area of eastern Zambia
Authors: Kubi C. , Billiouw M. , Van den Bossche P.
Published: August 2012

Trypanosomal infections in female Glossina morsitans morsitans were investigated in an area in the Eastern Province of Zambia between 1992 and 1994. A total of 4 416 flies were captured, aged using the ovarian ageing method and screened for trypanosomal infections in both the mouthparts, salivary glands and the midgut. Congolense-type infections were identified in 4.8 % of the flies. Vivax-type and immature infections were identified in 1.8 % and 6.8 % of the flies, respectively. The prevalence of con golense-type, vivax-type and immature infections increased with age. For vivax-type infections the age-prevalence relationship could be described by a model assuming a constant per capita rate of infection. For congolense-type and midgut infections, a polynomial term was added to the model significantly improving the fit. The per capita at which flies become infected was significantly higher for immature compared to mature infections. Observations strongly suggest that tsetse acquire new midgut infections at any age and that maturation of these infections is not limited to those obtained during the first blood meal.
Clinical, humoral and IFN g responses of cattle to infection with Mycoplasma mycoides var. mycoides small colony and attempts to condition the pathogenesis of the infection
Authors: Scacchia M. , Sacchini F. , Filipponi G. , Luciani M. , Lelli R. , Tjipura-Zaire G. , Di Provvido A. , Shiningwane A. , Ndiipanda F. , Pini A. , Caporale V. , Hubschle O.J.B.
Published: August 2012

Contagious bovine pleuropneumonia (CBPP), caused by Mycoplasma mycoides var. mycoides small colony (MmmSC), is one of the most important diseases of cattle in Africa. The role of innate or acquired cell mediated and humoral immunity in conferring protection against MmmSC infection has not yet been elucidated. On the other hand, the pathological lesions caused by the aetiological agent have been considered indicative of an immunopathological process. In this study ten naïve cattle were exposed to in-contact infection with animals infected by intubation with a strain of MmmSC. Clinical signs, antibody response, IFNg release and pathological changes at necropsy were analysed and compared with the events following in-contact infection of an equal number of animals kept under daily treatment with cyclosporine for the entire observation period of 84 days. Cyclosporine is a suppressor of the immune response related to the T-cell system. Under the conditions of the experiment, cyclosporine appeared to condition the pathogenesis of CBPP by delaying the events that follow infection, bringing further support to the possibility that the immune response may have an impact on the disease outcome.
Helminths of guineafowls in Limpopo Province, South Africa
Authors: Junker K. , Boomker J.
Published: August 2012

Between July 2005 and November 2006 the gastro-intestinal helminths of 15 Helmeted guineafowls and a single Crested guineafowl from Musina, Limpopo Province were examined, and in July and August 2005 helminths were collected from five Helmeted guineafowls from Mokopane in the same province. The acanthocephalan Mediorhynchus gallinarum, the cestodes Abuladzugnia gutterae, Davainea nana, Hymenolepis cantaniana, Numidella numida, Octopetalum numida, Ortleppolepis multiuncinata, Porogynia paronai, Raillietina angusta, Raillietina pintneri, Raillietina steinhardti and Raillietina sp. and the nematodes Ascaridia numidae, Cyrnea parroti, Gongylonema congolense, Hadjelia truncata, Sicarius caudatus, Subulura dentigera, Subulura suctoria, Subulura sp., Tetrameres numida and an unidentified subulurid were recovered. A single trematode species, Dicrocoelium macrostomum, was present in the liver. Mediorhynchus gallinarum, A. gutterae, O. multiuncinata, H. truncata and S. caudatus are recorded for the first time from Helmeted guineafowls, as well as from South Africa. South Africa is a new geographic record for D. macrostomum, G. congolense and D. nana. Subulura suctoria, G. congolense and H. truncata from the Crested guineafowl constitute new host-parasite associations.
Withdrawal periods and tissue tolerance after intramammary antibiotic treatment of dairy goats with clinical mastitis
Authors: Karzis J. , Donkin E.F. , Petzer I.M.
Published: August 2012

The aim of this study was to determine withdrawal periods (WP) and tissue irritation after administration of three intramammary antibiotics [Curaclox LC (Norbrook (ARK AH)], Spectrazol Milking Cow (Schering-Plough AH) and Rilexine 200 LC [Logos Agvet (Virbac)] in goats with clinical mastitis.Withdrawal periods in goats with clinical mastitis treated with Curaclox LC, were not significantly different from those recommended for use in cows (72 h) with (67 h) or without (48 h) the 24 h mandatory safety margin while Spectrazol caused a significantly longer withdrawal period (122 h) than that recommended for use in cattle with (60 h) and without (36 h) the 24h safety margin. The withdrawal period of clinical mastitis cases treated with Rilexine 200 LC was 48 h compared to the 96 h recommended for use in cows.A linear model of regression with factors influencing the WP in goats with clinical mastitis was as follows : WP = 30.21 + 4.692 (sampling time) + 22.11 (udder pathology) - 13.6 (floccules) - 0.00649 (milk yield).Somatic Cell Counts (SCC) of milk from udder halves with clinical mastitis ranged from 7 053 x 103 to 7 948 x 103 cells per mℓ without isolations of bacteria and between 6 476 x 103 and 8 479 x 103 cells per mℓ with isolations of bacteria. Most of the variation in SCC could not be explained and the California Milk Cell Test (CMCT) and SCC on their own were not reliable methods for mastitis diagnosis. However, CMCT and SCC were indicators of udder irritation. In goats without clinical mastitis, Spectrazol Milking Cow caused the least tissue irritation followed by Rilexine 200 LC and Curaclox LC. For goats with clinical mastitis, Rilexine 200 LC caused the least irritation, followed by Curaclox LC while Spectrazol Milking Cow caused the most irritation.
Distribution and population dynamics of ticks (Acari : Ixodidae) infesting sheep in Sennar State, Sudan
Authors: Mohammed M.S. , Hassan S.M.
Published: August 2012

A cross-sectional survey of ticks infesting sheep was conducted in Sennar State, Sudan. A total body collection of ticks was carried out at five localities Sennar town, Singa, Dinder, Abu Naama and Um Banein on two types of Desert sheep (Watish and Ashgar) on two farms at each locality at two monthly intervals for one year starting July 2002 to May 2003. Four tick genera and eight species were identified. They were Amblyomma lepidum, Hyalomma anatolicum anatolicum, Hyalomma truncatum, Rhipicephalus (Boophilus) decoloratus, Rhipicephalus camicasi, Rhipicephalus evertsi evertsi, Rhipicephalus guilhoni and Rhipicephalus muhsamae. A significant (P < 0.05) seasonal pattern of activity was observed for A. lepidum and R. guilhoni with peak activity occurring during rainy seasons. The highest mean number of ticks (7.26 + 0.58) was recorded at Abu Naama, while the lowest mean (3.61 + 0.31) was recorded in Sennar. Watish type sheep carried significantly (P < 0.05) more ticks than Ashgar type.
A check list of the helminths of guineafowls (Numididae) and a host list of these parasites
Authors: Junker K. , Boomker J.
Published: August 2012

Published and personal records have been compiled into a reference list of the helminth parasites of guineafowls. Where data on other avian hosts was available these have been included for completeness' sake and to give an indication of host range. The parasite list for the Helmeted guineafowls, Numida meleagris, includes five species of acanthocephalans, all belonging to a single genus, three trematodes belonging to three different genera, 34 cestodes representing 15 genera, and 35 nematodes belonging to 17 genera. The list for the Crested guineafowls, Guttera edouardi, contains a single acanthocephalan together with 10 cestode species belonging to seven genera, and three nematode species belonging to three different genera. Records for two cestode species from genera and two nematode species belonging to a single genus have been found for the guineafowl genus Acryllium. Of the 70 helminths listed for N. meleagris, 29 have been recorded from domestic chickens.
Culicoides biting midges at the National Zoological Gardens of South Africa : research communication
Authors: Labuschagne K. , Gerber L.J. , Espie I. , Carpenter S.
Published: August 2012

Culicoides biting midges (Diptera: Ceratopogonidae) are responsible for the transmission of a large number of pathogens to livestock and wild animals. In this study the presence of the genus, using light traps based at four different sites within the National Zoological Gardens of South Africa, was investigated during 2002-2004. In total, 37 species were recorded, including large numbers of Culicoides imicola Kieffer, 1913, which is responsible for the transmission of economically important arboviruses in South Africa, Europe, Middle and Far East. These results are discussed with reference to the wider Culicoides fauna in the Onderstepoort area of South Africa, their vector competence as well as biosecurity at the National Zoological Gardens.