Assessment of the nutritional status of indigenous scavenging chickens in Ada'a district, Ethiopia.

The nutritive values of scavenging feed resource bases and effects of season and chickens age on the latter were studied in smallholder farms in Aad'a, Ethiopia. The study included 210 households and 208 chickens. The mean weight of crop contents in all age groups ranged from 26.2 to 28.2 g, while it was 29.8 g and 24.7 g in the harvesting and non-harvesting seasons, respectively. Grains represented 48-49% of the mean weight of crop contents in all age groups and it was significantly higher (P < 0.05) during the harvesting season than the non-harvesting period in both age groups. Kitchen wastes were next in abundance (26-29%) and were significantly more abundant in non-harvesting season in growers only and in hens than in growers (P < 0.001). The dry matter, crude protein, crude fiber, calcium, phosphorous and metabolizable energy levels of crop contents were 91.1-92.5%, 12.9-15.5%, 4.17-7.07%, 0.43-0.90%, 0.28-0.38% and 3404.3-3636.2 Kcal, respectively. Crude protein, calcium and phosphorus levels were below the requirements for egg production and growth. The scavenging feed resource base was critically deficient in these nutrients during the harvesting season. As these nutrients are vital for production, supplementary feeds rich in these nutrients would probably result in increased egg production and optimum growth.

In vivo evaluation of immune responses in leishmaniasis: the use of cross-species leishmanin preparations for skin testing.

Skin test reactivity to two commercial preparations of Leishmania major leishmanin was evaluated in leishmaniasis patents from Ethiopia (L. aethiopica) and Nicaragua (probably L. braziliensis complex). The purpose of using different preparations of L. major was to evaluate whether L. major skin test antigens could generally be used to detect leishmaniasis due to L. aethiopica and L. braziliensis. One preparation was superior in identifying the majority (83-90%) of confirmed cases of local cutaneous leishmaniasis (LCL) from Ethiopia. In vitro responses to promastigotes of Leishmania spp. correlated well with leishmanin positivity to this preparation. The skin test antigen, which performed less well (showing a positive result in only 50% of the LCL patients), showed promise when used to test active and cured cases of leishmaniasis in Nicaragua (positive result in 92% of the active and cured patents). Cross-reacting Leishmania spp. may be considered for use in the preparation of standardized leishmanin antigen; however, differences in the commercial preparation or the diluent in which the parasites are prepared may affect antigenicity and thus its efficacy in detecting different forms of leishmaniasis in different geographic areas.

In leprosy the presence of mycobacteria in the nerve is an essential factor in the cycle and spectrum of Mycobacterium leprae infection.

A total of 220 untreated leprosy patients who underwent parallel skin and nerve biopsies are included in this study, which is intended to evaluate the extent of previously reported differences in bacillary load between skin and nerve lesions in leprosy and to describe the response of peripheral blood lymphocytes to Mycobacterium leprae antigens in such patients. In 161 patients out of the 220, the skin and nerve biopsies were diagnostic for leprosy. When patients were grouped according their skin and nerve lesions, the 3 groups observed were (1) paucibacillary skin and nerve lesions; (2) multibacillary skin and nerve lesions, and (3) paucibacillary skin and multibacillary nerve lesions. There was no observation of a group of patients with multibacillary skin and paucibacillary nerve lesions. In all patients with multibacillary nerve lesions, regardless of the type of skin lesions, a low response of peripheral blood lymphocytes to M. leprae was consistently noted. These results suggest that the bacillary load in the nerve is certainly one of the factors determining the immunological spectrum observed in leprosy.

Raised levels of tumour necrosis factor-alpha and neopterin, but not interferon-alpha, in serum of HIV-1-infected patients from Ethiopia.

Serum levels of tumour necrosis factor-alpha (TNF-alpha), neopterin and interferon-alpha (IFN-alpha) were determined by immunoradiometric assays in 60 HIV-1+ and 20 HIV-1- subjects from Ethiopia. Swedish samples were used as reference material. The Ethiopian HIV-1+ subjects were found to have significantly increased TNF-alpha and neopterin, but not IFN-alpha levels. Increased levels of TNF-alpha and neopterin were frequently found in Ethiopian asymptomatic subjects (37% and 47%), and the concentration increased in patients with AIDS (83% and 90% respectively). The levels of the two substances and the proportion of patients with higher TNF-alpha values were lower in the corresponding Swedish subjects. The proportion of sera with raised levels of IFN-alpha was very low (asymptomatic 4%, and AIDS 7%) in Ethiopian subjects. These results suggest a very early increase in the TNF-alpha production and activation of the cellular immune response, and a low level of IFN-alpha synthesis in the natural course of HIV infection in Ethiopia. The aberrations may contribute to a rapid progress of immunodeficiency and cachexia often seen in Ethiopian patients.

Thalidomide's effectiveness in erythema nodosum leprosum is associated with a decrease in CD4+ cells in the peripheral blood.

Thalidomide is well documented as being an effective drug in the treatment of erythema nodosum leprosum (ENL). The mechanism of action of thalidomide in ENL as well as the pathogenesis of ENL are yet to be fully determined. Lepromatous leprosy patients experiencing ENL have been reported to have an increase in the ratio of CD4+ to CD8+ cells in their blood and ENL skin lesions. Thalidomide has been shown to cause a decrease in the ratio of CD4+ to CD8+ lymphocytes in the blood of healthy males. This decrease was due to a significant reduction in the numbers of Cd4+ lymphocytes and an apparent increase in the numbers of CD8+ lymphocytes. In this study, thalidomide's effectiveness in halting chronic ENL and arresting a relapse into ENL was consistently associated with a decrease in the numbers of CD4+ lymphocytes in the blood of 2 male lepromatous leprosy patients.

Serum antibody specificities to Leishmania aethiopica antigens in patients with localized and diffuse cutaneous leishmaniasis.

In order to characterize the antigenic determinants of Leishmania aethiopica, we have analysed by immunoblotting the antibody reactivity of leishmaniasis patients with either the localized (LCL) or diffuse (DCL) clinical forms of disease. In this study we have compared the reactivity of antibodies from eight LCL and DCL patients to parasites isolated from each individual, or the parasite isolates of the other LCL and DCL patients studied. The immunoblot profiles of antibodies from LCL patients differed from the antibody profiles of DCL patients. Serum antibodies from LCL patients showed limited recognition of somatic antigens of less than Mr 50,000 which were recognized by antibodies present in DCL patients. A direct comparison of individual LCL and DCL patient derived promastigotes determined that the lack of antibody to these antigens in LCL patients was not due to the differential expression of these determinants by the LCL and DCL derived promastigotes. The results of this study suggest that although either LCL or DCL derived promastigotes express a wide variety of antigenic moieties which are potentially reactive with antibodies, only a subset of antibodies against these specificities develop in any individual patient, during active infection.

Differences in PCR reactivity between HIV proviruses from individuals in Ethiopia and Sweden.

The polymerase chain reaction (PCR), using primer pairs in the gag, pol, and env regions, was used in a comparative study of HIV-1 DNA in peripheral mononuclear blood cells from HIV-1-seropositive individuals in Ethiopia and Sweden. Although all Swedish samples were positive by PCR, the reactivity was more pronounced in samples from late stages than in those from early stages of infection. Six of nine Ethiopian samples from HIV-1-seropositive patients were positive by PCR, but the reactions were much weaker than those observed for Swedish samples, and in most cases seen with one primer pair only. These results suggest that the burden of HIV-1 DNA in peripheral mononuclear blood cells increases with advancing disease. PCR using primer pairs designed to detect HIV-1 infection in Europe and North America is not always suitable for the detection of HIV-1 infection in Ethiopia. The differences in PCR reactivity could possibly be a consequence of differences regarding host responses to the virus in the two countries, but more likely due to genomic differences between HIV-1 strains prevalent in Ethiopia and Sweden.