Heterophile antibodies to chicken erythrocytes in sheep infected with Trypanosoma congolense.

High hemagglutinin titres against chicken erythrocytes were detected in the sera of Trypanosoma congolense-infected sheep. Adsorption of sheep sera with solubilized T. congolense resulted in marked reduction of hemagglutinin titre. Heat inactivation of the sera at 56 degrees C for 30 min had no demonstrable effects on the hemagglutinin titre. Sera collected from the sheep before trypanosome infection did not agglutinate chicken erythrocytes. On the other hand, erythrocytes of horse, donkey and dog were agglutinated at very high titres by sera collected both pre-infection and during the course of infection. Erythrocytes from bovine and caprine species were not agglutinated by contemporaneous sera at both low and high dilutions. Hemagglutinin titres for chicken erythrocytes returned promptly to pre-infection levels in chemotherapeutically terminated infections. The brand of trypanocide used, had no effect on the course of the hemagglutinin titre's return to a normal level.

Isolation and identification of African horse sickness virus during an outbreak in Lagos, Nigeria.

An outbreak of African horse sickness involving two horse stables in Lagos, Nigeria, was investigated. Inoculation of blood from infected horses into suckling albino mice resulted in isolation of a virus which was identified as African horse sickness virus by the complement fixation test. The clinical, pathological and epizootiological findings (reported elsewhere) were consistent with African horse sickness. Potential threats of the epidemic to international horse trade are briefly highlighted.

Haematology of experimental babesiosis and ehrlichiosis in steroid immunosuppressed horses.

An investigation was carried out to study the haematology of steroid immunosuppressed horses experimentally infected with Babesia equi and Ehrlichia equi, separately or simultaneously. Horses infected with both pathogens showed less marked changes in their haematology than those inoculated with either pathogen separately. This appeared to result from early elimination of the more pathogenic Babesia as Ehrlichia spread through the granulocytes. The apparent suppression of Babesia by Ehrlichia is of field clinical importance and merits further investigation for its apparent useful potentials in the control of babesiosis in endemic areas.

Complement fixing antibodies against arboviruses in horses at Lagos, Nigeria.

Sixty-two sera horse collected from two stables at Lagos, Nigeria, were tested for complement fixing antibody to 8 arbovirus antigens; Chikungunya, Igbo-Ora, Yellow fever, Wesselsbron, West Nile, Potiskum, Uganda S and Rift Valley fever. Ten per cent of the horse sera examined contained CF antibody to one or more of the test antigens and indicated considerable arbovirus activity in the two stables. Reactions with flavivirus antigens were most common and the highest antibody titres were obtained with Wesselsbron and Yellow fever viruses. Eleven per cent of the sera tested reacted with alphavirus antigens while 10 per cent were positive for Rift Valley fever virus CF antibodies.

Large animal hepatotoxic and nephrotoxic plants.

The hepatotoxic and nephrotoxic plants of large domestic animals have been reviewed. The most important ones are those widely distributed as weeds over pastures, negelcted forests and grasslands, those used as ornamentals, the nitrate concentrating forage crops, and the cyanophoric plants. Crotolaria spp, the ragwort (Senecia jacobaea), the lantana spp. and heliotopum are common hepatoxic plants. Amaranthus retroflexus, Datura stramonium, Solanum rostratum, and the castor oil plant (Ricinus communis) are nephrotoxic plants.