Characterisation of Theileria parva isolates from Kiambu district, Kenya.

Four Theileria parva isolates from Muguga area of Kiambu district, Kenya, were used to establish schizont-infected cell lines. Their protein antigens were then separated by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS page). The isolates were subsequently subjected to protein analysis and characterisation by the western immunoblotting technique. Probing for the polymorphic immunodominant molecule (PIM) was done using monoclonal antibody no. 4. SDS page detected up to 20 protein antigens of molecular mass 35,000-180,000 Da. The western blot analysis revealed a greater heterogeneity in the molecular mass (M(r)) of PIM than previously thought. The M(r) of PIM varied between 80 and 90 kDa. The isolates further revealed different densities of surface epitopes with variable reaction to the monoclonal antibody. The implications of these findings to the epidemiology of east coast fever and immunisation programmes are discussed.

Application of immunoaffinity chromatography and enzyme immunoassay in rapid detection of aflatoxin B1 in chicken liver tissues.

Existing physicochemical analytical methods for the determination of aflatoxins in animal tissues are expensive, cumbersome, and hazardous. To offer an alternative to these methods, a novel and highly sensitive immunochemical method for the rapid detection of aflatoxin B1 (AFB1) in chicken liver tissues is described in this study. Liver tissues were homogenized with cold methanol-acetone (50:50), followed by AFB1 extraction with methanol-acetone-PBS (25:25:50). The tissue extracts were, with or without further purification by immunoaffinity chromatography (IAC), applied to a highly sensitive direct ELISA for determination of AFB1. The detection limits for this assay were 15 +/- 0.77 pg/mL when standards and samples were dissolved in methanol-PBS (10:90) and 17 +/- 2.0 pg/mL when methanol-acetone-PBS (5:5:90) solution was used. The average recoveries of AFB1 were 54.3 to 65.5% in artificially contaminated tissue samples at 1 to 5 ng/g. In samples spiked with AFB1 at 1 ng/g, the method had diagnostic sensitivity and specificity of 100% for samples processed with IAC and 91.7 and 100%, respectively, for samples without IAC purification. The test was successfully applied to the detection of AFB1 in liver tissues from chickens that were experimentally dosed with AFB1. It is hoped that this test will be applicable in rapid detection of aflatoxins in poultry meats and in diagnosis of aflatoxicosis in chicken.

Comparative parasitological and haematological changes in two breeds of sheep infected with Fasciola gigantica.

Twelve each of Red Masai and Dorper sheep, aged between 6 and 9 months, were acquired from a Fasciola-free area of eastern Kenya. Each breed was divided into two groups of 6. The sheep in one group of each breed were experimentally infected with 400 viable metacercariae of Fasciola gigantica. The other group of 6 sheep of each breed remained as uninfected controls. The animals were monitored regularly for any evidence of disease. Blood samples taken weekly revealed a general reduction in red cell counts and packed cell volume, which was much faster in the infected Dorper sheep than in the Red Masai. This reduction started from the tenth week after infection and persisted to the end of the experiment 18 weeks post infection (PI). The absolute eosinophil counts rose in all the infected animals, but the values were higher among the Dorper than among the Red Masai. Patency occurred at weeks 12 and 13 PI in the Red Masai and Dorpers, respectively, with the latter shedding significantly more fluke eggs. The worm recovery rates were higher among the Dorpers than among the Red Masai, though not significantly so. On the basis of egg counts and clinicopathology, the Dorper sheep were considered to be more susceptible to F. gigantica infections.

A comparison of serum biochemical changes in two breeds of sheep (Red Masai and Dorper) experimentally infected with Fasciola gigantica.

Twelve Red Masai and 12 Dorper sheep aged between 6 and 9 months, were acquired from a fluke-free area and sheep of each breed divided into two equal groups of six. Each animal in one group of each breed was experimentally infected with 400 viable metacercariae of Fasciola gigantica. The other groups acted as uninfected controls. Blood samples were taken at weekly intervals for the determination of serum bilirubin, albumin, and gamma glutamyl transferase levels. Following the establishment of infection, albumin levels declined in both breeds of infected animals without any significant difference between the two breeds. However, serum bilirubin and gamma glutamyl transferase (GGT) in the infected animals were elevated significantly more in the Dorper than in the Red Masai sheep. Based on these findings, it would appear that Dorper sheep are more susceptible to the infection than Red Masai sheep.

An unusual presentation of suspected oedema disease of swine in Kenya.

From a group of 11 recently weaned pigs, 4 were reported to be sick. Clinical examination of the sick pigs revealed marked dyspnoea, bluish-red discolouration of the skin, incoordination and difficulty in walking. Bacteriological examination of the gut contents of 2 pigs that had died earlier yielded pure cultures of haemolytic Escherichia coli. Post mortem examination of the remaining 2 pigs that died subsequently revealed progressive pulmonary collapse. One of these also showed subcutaneous oedema of the head and marked oedema of the mesentery of the spiral colon and oedema of the brain. Microscopically there was pulmonary alveolar collapse and degenerative changes in the liver. On the basis of the clinical signs, isolation of haemolytic E. coli and the post mortem findings, a diagnosis of oedema disease was made.

Donkey klossiellosis in Kenya.

Out of eight donkeys examined, two had gametogonic and sporogonic stages of Klossiella equi in their kidneys. Gametogonic stages included microgametocytes and macrogametocytes, some of them in syzygy. They were found in enlarged parasitophorous vacuoles situated in epithelial cells of the renal tubules. Sporonts were seen in the epithelial cells protruding into the tubular lumen while sporoblasts, sporocysts and sporozoites were found freely in the tubular lumen. Entire sporocysts were rarely encountered but sporozoites liberated from the ruptured sporocysts could be seen. No inflammatory reaction could be attributed to the presence of these parasites.

Sarcocystis-like organisms in musculature of a domestic dog (Canis familiaris) and wild dogs (Lycaon pictus) in Kenya.

Three of six wild dogs (Lycaon pictus) which died of rabies, and one Alsatian dog which died of adenocarcinoma, were found to harbour sarcocysts in their cardiac and/or skeletal muscles. The bradyzoites and metrocytes of the cysts were smaller than those seen in a lion infected with Microbesnoitia leoni and the common Sarcocystis spp. found in ruminants. It is proposed that Lycaon pictus is the natural intermediate host of the unidentified Sarcocystis-like species.

Changes in the bovine udder quarters naturally infected by Corynebacterium bovis.

Of 272 bovine udder quarters studied for mastitis, 19 of them naturally infected with Corynebacterium bovis alone, were compared with 16 others infected by C. bovis together with other bacteria and another 36 non-infected quarters. While there was no significant difference in milk somatic cell counts between the quarters infected by C. bovis alone and those affected by C. bovis together with other bacteria (33.37 +/- 20.28 X 10(3) and 33.86 +/- 23.18 X 10(3)/ml of milk, respectively), there was a significant difference between these and the non-infected quarters (5.60 +/- 3.23 X 10(3)/ml of milk). Microscopically, quarters infected by either C. bovis alone or C. bovis in combination with other bacteria had inflammatory changes in the teat cisterns, Furstenberg's rosettes and/or mammary parenchyma. The non-infected quarters had no changes. In all 82 quarters no pathological changes could be seen in the teat canals.

Microscopic changes in infected bovine teats.

Two hundred and fifty-two teats from the udder quarters of 68 dairy cows were studied by bacteriological examination of quarter milk samples and microscopic examination of the teats. Of 252 quarters, 169 teats showed inflammatory changes, while 83 were of normal appearance. The inflammatory changes consisted of either neutrophil infiltrations, mononuclear cell infiltrations and fibrosis, or a combination of these changes. The reaction was restricted to the teat cisterns and/or Fürstenberg's rosettes, but very rarely also in the teat canal. In 136 of 169 cases, the inflammatory reaction was associated with bacteria in the milk, while in 33 cases no bacteria could be recovered from milk, in spite of inflammatory changes in the teat structures. Only 36 of 83 of normal teats were bacteriologically positive.

Healing of dehorning wounds.

Open wound healing following dehorning using a wire saw was observed in 25 cattle aged between 1 and 5 years. Initially, there was a marked thickening of the scab over the wound as a ridge near the skin margin. A pale yellow to pink membrane then developed from the sides of the frontal sinus opening. Granulation tissue formed to fill the frontal sinus opening before healing by epithelization, followed by wound contraction. In some animals a bony horn stump projecting about 2-3 mm above the wound surface appeared which underwent osteosis; the dead bone gradually loosened and fell off during the healing process; histological sections revealed the presence of numerous osteoclasts lining the bone spicules. The presence of the frontal sinus and the stump of the horn processes left after dehorning are factors that make the healing of an open dehorning wound unique compared with other wounds.

Arteriosclerosis and related lesions in rabbits.

Eleven female rabbits, mainly of the NZW breed, aged between 1 and 3.5 years, were examined post mortem. All had originated over the years 1982 to 1987 from the same rabbitry where they had been fed on pellets from the same manufacturer. Apart from one rabbit, all had a history of progressive loss of bodily condition and six of them had also been infertile. Grossly, most of them were emaciated and their arteries were hardened. In some, hepatopathy, nephropathy and pulmonary emphysema were evident. In one case, mummified foetuses were recovered from the abdominal cavity. Microscopically, degenerative changes and calcification were found in the walls of arteries, kidneys, lungs, hearts and ovaries.

Leishmaniasis in Kenya: description of leishmaniasis of a domestic goat from Transmara, Narok District, Kenya.

Extensive research has been carried out in Eastern Africa for animal reservoirs of both visceral and cutaneous leishmaniasis. The domestic dog has been the only domestic animal so far implicated as a possible reservoir for visceral leishmaniasis. For cutaneous leishmaniasis caused by Leishmania aethiopica, the hyrax and the giant rat are the proven reservoirs of the disease while several species of rodents have been demonstrated to harbor L. major. Recent studies conducted in domestic animals in West Pokot led to the first isolation of leishmanial parasites from a domestic goat, a close associate of man in the vast endemic leishmaniasis foci. Consequent encounter of a clinical case of the disease is the basis for this paper. It is the first autochthonous case in Eastern Africa. The goat originated from the Western escarpments of the Rift Valley which are known to harbor L. aethiopica. Clinical signs included lesions, indurations, and enlargement of lymph nodes. Parasitological and pathological investigations revealed amastigotes in various tissues. Cultures of the affected tissues produced promastigotes.

Pneumonia in goats following administration of live and heat-killed Pasteurella haemolytica.

Six of 7 and 3 of 4 goats inoculated with live and heat-killed P. haemolytica (biotype-T), respectively, had pneumonia at necropsy. Clinically, the pneumonia was only detected in 8 of 9 goats with diseased lungs. One goat died of a fibrinous pneumonia which was associated with a profuse growth of both P. haemolytica (biotype-T) and P. multocida and a limited growth of Escherichia coli from the lungs. In the remaining 8 goats with lung lesions, the pneumonia was of the proliferative type, with only some showing the exudative feature. Five of these goats (including 3 controls) had bacteriologically sterile lung lesions, while the other 3 yielded P. haemolytica (biotype-T) and in one of them, chlamydia were also isolated. P. haemolytica (biotype-T) and P. multocida were isolated from 1 of 2 goats with normal lungs.

Nasal bacterial flora of clinically normal goats.

An enclosed swab assembly was employed to collect nasal mucus from 45 clinically normal goats. Eleven bacterial species were isolated from their nasal cavities. Pasteurella haemolytica and Pasteurella multocida were the most important isolates.