Pathogenicity and chemotherapy of Plasmodium durae in experimentally infected domestic turkeys

Only 3 out of 8 South African isolates of Plasmodium durae used in 524 turkeys in 161 passages caused approximately 50% mortality, a further 3 produced approximately 10% mortality while 2 were found to be apathogenic. Exoerythrocytic schizonts were the main pathogenic stage. In most survivors the effect on mass gains was minimal. Twelve drugs currently available for use in poultry, as well as chloroquin phosphate, were tested for their activity against experimental infections with Plasmodium durae in domestic turkeys. While chloroquin phosphate showed a certain degree of effectivity, Amprolium, Amprolium + Ethopabate, Maduramycin, Toltrazuril, Metronidazole, Furazolidone, Enrofloxacin and Sulfamethoxypyridazine + Trimethoprim were ineffective. Halofuginone and Penta-Sulfa at a high dose had some protective effect. At high doses Sulfachloropyrazine protected from mortality without affecting the parasitaemia, while Sulfamonomethoxine suppressed parasitaemia without entirely protecting from mortality. From these data it is concluded that Halofuginone has a potential as possible chemoprophylactic. While a combination of Sulfamonomethoxine and Sulfachloropyrazine could be used in the treatment of outbreaks in the field.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

A host-parasite list of the haematozoa of domestic poultry in sub-Saharan Africa and the isolation of Plasmodium durae Herman from turkeys and francolins in South Africa

An annotated host-parasite list of the blood parasites of domestic poultry in sub-Saharan Africa is presented. This list contains the haematozoa found in domestic waterfowl (ducks, geese and muscovies) and phasianids (turkey, fowl and peafowl). In South Africa Plasmodium durae was isolated from 4 out of 8 backyard turkeys, from 3 out of 26 Swainson's francolins and from 1 redwing francolin, but not from 20 helmeted guineafowls and 9 greywing francolins. This points at Swainson's and redwing francolins as being the main natural hosts of P. durae in South Africa. The increase in the period of prepatency after intramuscular subinoculation as compared with the intravenous route was found to correspond to that of a 1 000 fold dilution of an intravenous inoculum of parasitized blood. This delay was not due to an intervening cycle of exoerythrocytic schizogony, but to large numbers of the injected erythrocytes apparently not finding their way into the circulation of the new host.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

Host range, survival in dead hosts, cryopreservation, periodicity and morphology of Plasmodium durae Herman in experimental infections

In experimental infections, fowl , duck, guineafowl and canary were refractory to Plasmodium durae, which in Japanese quail produced low and transient infections, but a high and long-lasting parasitaemia in a Lady Amherst pheasant. Heart, blood and brain of dead hosts injected into turkeys, allowed the recovery and further passaging of the live parasite. This technique could be useful for the recovery of malaria parasites from suspect postmortem material. Intravenous infection produced parasitaemias in chicken and turkey embryos, while attempts at allantoic-sac infections of chicken embryos were unsuccessful. A certain degree of periodicity of schizogony was demonstrated. The South African isolates of P. durae had smaller schizonts than those described from East and West Africa, with 2-14 merozoites (mostly four) . Some strains did not produce mature gametocytes in the experimental hosts. Exoerythrocytic schizonts of P. durae are depicted in this paper for the first time.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat X Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

Avian pulmonary hypertension syndrome. IV. Increased right ventricular mass in turkeys experimentally infected with Plasmodium durae

Infection of young turkeys with Plasmodium durae produced a significant increase in the mean relative right ventricular mass from 0,172 in the controls to 0,208 in the infected group. Although turkeys react less strongly to hypoxia than broiler chickens, the similarity of this finding to that previously reported in broilers infected with Aegyptianella pullorum suggests that the hypoxic effect of the anaemia produced by these blood parasites causes the pulmonary hypertension and subsequent right ventricular hypertrophy.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.lmchunu2014mn201

Broiler ascites : a review of the ascites work done at the poultry section of the Onderstepoort Veterinary Institute 1981-1990

Broiler ascites, first seen in the form of a high altitude disease, has increased in importance world-wide in direct proportion to the improvement in growth performance of modern broilers. At the same time, the incidence has spread gradually from high altitude (above 2000 m) down to sea level, which gave rise to proposals of alternative causes including infections, toxins and metabolic disorders. Our work centred on anatomical and physiological aspects and included hypoxia models, chemotherapy and selection for genetic resistance. The latter led to the development of ascites-resistant lines, which allowed resistant stock to become commercially available in South Africa. The closure of the Poultry Section of the Onderstepoort Veterinary Institute brought ongoing ascites research to an abrupt end and some of the completed work was never published. This review of completed, ongoing and planned ascites work was at the time compiled as final report to the Director of the Institute in 1990. It came to light again recently and has been edited for publication. It also includes a new hypothesis on the reasons for the susceptibility of the domestic fowl and particularly broilers to hypoxic ascites.http://journals.cambridge.org/WP

Pentastomid parasites of the family Sebekidae Fain, 1961 in West African dwarf crocodiles Osteolaemus tetraspis Cope, 1851 from the Congo, with a description of Alofia parva n. sp

The lungs and viscera of 23 dwarf crocodiles (Osteolaemus tetraspis) obtained from markets in Brazzaville, were examined for pentastomid infection. Twenty-one animals were infected and harboured a total of 82 pentastomids, all belonging to the family Sebekidae and representing at least two genera and three species. Sebekia okavangoensis Riley & Huchzermeyer, was present in the body cavity and lungs; the other two species were restricted to the lungs. Alofia parva n. sp. (14 female; 10 male) was unusual in that the fulcrum supporting the anterior hooks carried a cowl-like extension. The remaining species, provisionally allocated to the genus Sebekia, could not be classified to the generic level with certainty.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

Multifactorial mortality in bongos and other wild ungulates in the north of the Congo Republic

Wildlife mortality involving bongos, Tragelaphus eurycerus, and other ungulates was investigated in the north of the Congo Republic in 1997. Four bongos, one forest buffalo, Syncerus caffer nanus, and one domestic sheep were examined and sampled. Although an outbreak of rinderpest had been suspected, it was found that the animals, which had been weakened by an Elaeophora sagitta infection and possibly also by adverse climatic conditions, had been exsanguinated and driven to exhaustion by an unusual plague of Stomoxys omega.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat v.9 was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.FAO.mn201

Broiler pulmonary hypertension syndrome. III. Commercial broiler strains differ in their susceptibility

Broilers of 4 different commercial strains were kept during winter at an altitude of 1 350m. The birds were slaughtered at weekly intervals and their relative right ventricular mass (pulmonary arterial pressure index = API values) determined. In addition, the incidence of ascites was recorded. Two of the strains suffered high losses from ascites, while the other 2 showed a certain degree of resistance. The former 2 groups had a higher mean API and a greater percentage of high API values in clinically normal birds than the other 2 groups. The group with the lowest incidence of ascites achieved the highest mean live mass at 51 days. There was also a decrease in mean API with age in clinically normal birds. There was no difference in the incidence of ascites between males and females.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.lmchunu201

Aerobic intestinal flora of wild-caught African dwarf crocodiles Osteolaemus tetraspis

Intestinal contents were collected from wild-caught African dwarf crocodiles (Osteolaemus tetraspis) in 1993 and 1995 which were slaughtered at urban markets in the Congo Republic. The samples were kept frozen and brought back to Onderstepoort for aerobic culture. Out of 29 specimens, 33 species of bacteria and 20 species of fungi were isolated. The bacteria included three isolates of Salmonella and eight isolates of Escherichia coli, most of the latter being rough strains. The flora of individual specimens contained 1-5 bacterial and 0-5 fungal species. Neither Aeromonas hydrophila nor Edwardsiella tarda were isolated from any of the samples.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat v.9 was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

A host-parasite catalogue of the haematozoa of the sub-Saharan birds

The prevalence of avian haematozoa in 826 species of birds representing 73 families of sub-Saharan birds as recorded in the literature or in the files of the International Reference Centre for Avian Haematozoa and the Veterinary Research Institute is presented. The most commonly occurring blood parasites were members of the genus Haemoproteus which were represented by 63 species which occurred in 19,1% of the sample. Twenty-five species of Leucocytozoon were recorded in 8,3% of the birds and represented the second most frequently encountered group of haematozoa. Species of Plasmodium, Trypanosoma, and filarioids (as microfilariae) occurred in 3,5%, 2,5% and 2,8% respectively of the birds sampled; species of Aegyptianella, Atoxoplasma, Babesia and Hepatozoon were infrequently seen. An annotated list of the birds examined for haematozoa is presented and brief descriptions of the species of Haemoproteus and Leucocytozoon in birds of the sub-Saharan zone are included.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.Foundation for Research Development. Natural Sciences and Engineering Research Council of Canada.mn201