Non-immune control of trypanosomosis: in vitro oxidative burst of PMA- and trypanosome-stimulated neutrophils of Boran and N'Dama cattle

An in vitro assay that measures the generation of superoxide anions (O₂ˉ) was used to assess the level of oxidative burst of phorbol myristate acetate (PMA) - and trypanosome-stimulated neutrophils isolated from healthy Boran and N'Dama cattle, and those infected with Trypanosoma congolense. PMA stimulation of healthy bovine neutrophils resulted in between 300-400% increase in O₂ˉ generation. Neutrophils of Boran cattle exhibited slightly higher, but insignificant O₂ˉ generation capacity than those of the N'Dama breed. In vitro stimulation by trypanosomes of neutrophils isolated from Trypanosoma congolense-infected cattle caused significant increases in O₂ˉ generation, especially on days 14, 28 and 42 post-infection, of both breeds of cattle. No significant differences were observed in O₂ˉ generation capacity of the neutrophils of both breeds of infected cattle throughout the period of assay. The results of this study have shown that PMA and trypanosomes do cause an enhanced in vitro oxidative burst, hence trypanosome phagocytosis and killing activity of neutrophils. Neutrophils have been shown to play very significant roles in parasite clearance, hence reduction of trypanosome parasitaemia. The rates of both in vitro generation of O₂ˉ and trypanosome phagocytosis over time did not differ significantly between Boran and N'Dama breeds of cattle, even during T. congolense infection in this study. Hence, it may be inferred that sustained and higher parasitaemia, more pronounced neutropenia, inadequate bone marrow response and less effective trypanosome-specific immune response, rather than defective neutrophil trypanosome destruction, may be the problem of trypanosusceptible cattle breeds.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

Effect of Temperature on the Oviposition Capacity of Engorged Adult Females and Hatchability of Eggs of Dog Ticks: Rhipicephalus sanguineus and Heamaphysalis leachi leachi (Acari: Ixodidae)

Effects of temperature on the oviposition capacity of engorged adult females of Rhipicephalus sanguineus and Heamaphysalis leachi leachi and on the hatching pattern of their eggs were investigated under laboratory conditions. The temperatures of maintenance were 15°C, 20°C, 25°C, 30°C and 37°C at 85% relative humidity (R.H). The pre-oviposition periods of engorged adult females of R.sanguineus and H. leachi leachi increased as the incubation temperature became low from 30°C to 15°C. There was a significant difference (p < 0.05) in the pre-oviposition periods of R. sanguineus and H. leachi leachi at all the maintenance temperatures. The number of eggs oviposited by adult females of R.sanguineus and H. leachi leachi decreased as the incubation temperature dropped from 30°C to 15°C. The mean numbers of eggs produced respectively by 0.06g and 0.12g R. sanguineus female ticks at 37°C were 278.00 + 3.46 and 955.33 + 4.90 while no egg was laid by the same weights of female H. leachi leachi at the same temperature. The eggs of both species did not hatch at 150C. At 370C the eclosion period of R. sanguineus was 17 days while the eggs of H. leachi leachi did not hatch. The mortality rates of eggs of H. leachi leachi, (56.2, 16.8 and 16.6%) were higher than those of R. sanguineus, (17.6, 10.3 and 10.2%) at 20°C, 25°C and 30°C respectively. It is concluded that R.sanguineus has greater resistance to the deleterious effect of extreme temperatures than H. leachi leach

Efficacy of some anthelmintics used in porcine practice in Ibadan, Nigeria

Ninety three (93) pigs (crosses of Large white, Landrace, Hampshire and Duroc) were screened for gastrointestinal worms before and after treatment with the following drugs: Levamisole, Albendazole, Morantel citrate, Piperazine., thiabendazole and Ivermectin. The anthelmintic efficacy (measure as reduction egg per gram (EPG) of faeces) observed ranged as follows: Ivermectin – 100% Levamisole – 89%; Thiabendazole – 78.0%; Albendazole – 73.2%; Morantel citrate – 78.7% and Piperazine – 70.6% Ivermectin and Albendazole cleared the Trichuris worms that were not cleared by Morantel, Piperazine and Levamisole. A combination of good hygiene and strict deworming programme will go a long way in eradication of pathogenic helminths of livestock

Swine farm infestation with Culicoides species (biting midges) in Zaria, Nigeria

Collection of biting midges within a piggery farm using black-light suction traps revealed the presence of diverse species of Culicoides. Out of a total of one thousand four hundred and five (1,405) midges caught, one thousand three hundred and sixty-six (1,366) were identified as species in the genus Culicoides while the remaining thirty-nine (39) were unidentified members in the family Ceratopogonidae. The identified Culicoides were further classified into eight species based on their morphological characteristics as C. imicola, C. pycnostictus, C. oxystoma, C. milnei, C. subschultzei, C. enderleini, C. nevilli and C. krameri. There was dominance of females (93.67%) over the males (6.33 %) from the total collection. The presence of Culicoides species infesting pigs was established and the identified Culicoides species were incriminated to be mammophilic in feeding. Recommendation is made to determine the blood meal source and possibility of disease transmission.Keywords: Culicoides species, Ceratopogonidae, Light-trap, Nigeria, Piggery, Zari

Detection of Culicoides-biting midges (Diptera: Ceratopogonidae) associated with a household in Makurdi, Benue State, Nigeria

An investigation was carried out with the aim of identifying the species of insects that was responsible for inflicting very painful bites on the inhabitants of a household in the city of Makurdi, Benue State, Nigeria. The insects were collected using light suction insects’ traps and identification was achieved morphologically through microscopic examination of permanent slide sealed with Canada balsam in xylene. The investigation revealed the presence of a single species of biting-midges which was identified as Culicoides oxystoma based on characteristic wing patterns, the shape of the genitalia in male, third palpal segment of the maxillary palp and the spermathecae in female. The collected midges showed female dominance of 90.23% while male showed 9.77% prevalence. Culicoides oxystoma could be considered as an opportunistic anthropophilic species capable of breeding around banana plants.Keywords: Ceratopogonidae; Makurdi; household; Culicoides oxystoma; blood suckin