Genetic diversity of indigenous chickens from selected areas in Kenya using microsatellite markers.

In this study, indigenous chickens were collected from eight different regions in Kenya and kept at InCIP-Egerton University. These were studied using eighteen microsatellite markers to determine genetic variation. Statistics related to genetic variation were estimated using GenALEx6. Mean percentage polymorphic loci (PPL) was 96.71% and 4% genetic variance (p ≥ 0.003) was seen between the eight populations. MCW0123 marker had the highest genetic variance of 13% among populations (p ≥ 0.003) at 95% CI. Mean He ranged from 0.351 ± 0.031 (SIB) to 0.434 ± 0.022 (BM) with a grand mean He of 0.399 ± 0.011 across the populations using the microsatellite markers. Nei's genetic distance ranged from 0.016 (SIB and WP) to 0.126 (NR and SIB). DARwin6.501 analysis software was used to draw the population dendrogram and two major population clusters were observed, also seen with PCoA. This study found a lot of genetic variation and relatedness within and among populations. Based on the phylogenetic tree result, it is concluded that the clustering of the chicken populations in the present study is not based on geographical proximity. The microsatellite markers used in this study were suitable for the measurement of the genetic biodiversity and relationship of Kenyan chicken populations. These results can therefore serve as an initial step to plan the conservation of indigenous chickens in Kenya.

Quantitative Reference Ranges for Fasting Profiles and Oral Glucose Tolerance Test for Healthy Adults in Metropolitan Region of Nairobi; Kenya

Purpose:To establish quantitative reference ranges for fasting profiles and oral glucose tolerance test for healthy adults in metropolitan region of Nairobi. Methods: A prospective study carried out on 871 healthy subjects from the metropolitan region of Kenya. Results: The fasting profile parameters investigated were fasting blood glucose (FBG); total cholesterol (TC) triglycerides (TG); high density lipoprotein cholesterol (HDLC); low density lipoprotein cholesterol (LDLC) and TC/HDLC ratio. In addition; oral glucose tolerance test (OGTT) was also investigated. Eight hundred and seventy one (871) healthy study subjects were involved in the study. Established reference ranges were as follows: FBG (venous whole blood) (2.1 - 5.7) mmol/L; TC (2.9 - 6.4) mmol/L; TG (0.44- 2.44); HDL C (1.1 - 2.1) mmol/L; LDLC (1.1 - 4.3) mmol/L; TC/HDLC ratio (1.1 - 5.4). Established reference ranges for oral glucose tolerance test (OGTT) were as follows: baseline/fasting blood glucose capillary whole blood (3.2-5.4) mmol/L; half hour (4.7-8.9) mmol/L; one hour (4.4-9.8) mmol/L; one hour and half (4-8.1) mmol/L and two hours (3.4-7.2) mmol/L. Results for gender differences for the studied parameters were as follows: FBG (p=0.124); TC (p=0.205); TG (p=0.705) HDLC (p= 0.52); LDLC (p=0.417) and TC/HDLC ratio (p=0.359). On the other hand; the gender results for timed OGTT were as follows: 0 hour (p=0.123); half hour (p=0.479); one hour (p=0.412); one hour and half (p=0.596)) and two hours (p=0.630). Hence there were no gender disparities for the parameters in the studied adult Kenyan population. Conclusion: Since the established reference ranges are a reflection of the Kenyan adult population our clinical chemistry laboratory reports interpretations will henceforth be independent of what has been quoted in literature. Likewise effective diagnosis and management of glucose and lipids pathological disorders will be achieved by the use of established adult Kenyan reference ranges

Aggravation of pathogenesis mediated by ochratoxin A in mice infected with Trypanosoma brucei rhodesiense.

Mice fed 1.5 mg ochratoxin A (OTA) per kg body weight and infected with Trypanosoma brucei rhodesiense were compared with trypanosome-infected placebo-fed and uninfected OTA-fed controls. Uninfected OTA-fed mice showed fever, lethargy, facial and eyelid oedemas, mild hepatitis and nephritis, and high survival. Infected placebo-fed controls had mean pre-patent period (PPP) of 3.26 days, lethargy, dyspnoea, fever, facial and scrotal oedema, survival of 33-65 days, reduced red cell counts (RCC: 10.96-6.87x106 cells/microl of blood), packed cell volume (PCV: 43.19-26.36%), haemoglobin levels (Hb: 13.37-7.92 g/dL) and mean corpuscular volume (MCV) of 37.96-41.31 fL, hepatosplenomegaly, generalized oedemas, heart congestion, hepatitis and nephritis. Compared to infected placebo-fed controls, infected OTA-fed mice had significantly (P<0.05) shorter mean PPP (2.58 days), reduced survival (6-47 days), more pronounced fever and dyspnoea. The latter had significantly (P<0.05) reduced RCC (10.74-4.56x106 cells/microl of blood), PCV (43.90-20.78%), Hb (13.06-5.74 g/dL), increased MCV (39.10-43.97 fL), severe generalized oedemas, haemorrhages, congestion, hepatic haemosiderosis, hepatitis, nephritis, endocarditis, pericarditis and exclusively, splenic macrophage and giant cell hyperplasia, expanded red pulp and splenic erythrophagocytosis. It was concluded that OTA aggravated the pathogenesis of T. b. rhodesiense infection in mice, and should therefore be taken into consideration during trypanosomosis control programmes.

Subclinical nephrotoxicity associated with occupational silica exposure among male Kenyan industrial workers.

OBJECTIVE: To determine early signs of renal injury due to occupational silica exposure. DESIGN: Cross-sectional analytical research. SETTINGS: Kenyatta National Hospital for the referent population and Clayworks ceramics, bricks and tiles factory for the assessment of occupational silica exposure. SUBJECTS: Thirty three non-smoking silica-exposed male industrial workers and 38 non-smoking male referents participated in this study. RESULTS: Silica-exposed males excreted significantly increased levels of U.TP, U.Malb, U.ALP, U.y-GT and U.LDH compared to referent males. Among the silica-exposed males, U.Si negatively correlated significantly with age, U.TP correlated significantly to each of U.ALP and U.LDH. However, no correlation was observed between work duration and U.Si. CONCLUSION: The present study shows that there is associated glomerular and proximal tubular damage among silica exposed workers which is not duration related and is seemingly subclinical and nonprogressive and urinary silica levels appears to be similar in all groups and are not affected by exposure and work duration: the reason for which is unclear.

Detection of Anaplasma antibodies in wildlife and domestic species in wildlife-livestock interface areas of Kenya by major surface protein 5 competitive inhibition enzyme-linked immunosorbent assay.

The seroprevalence of Anaplasma antibodies in wildlife (eland, blue wildebeest, kongoni, impala, Thomson's gazelle, Grant's gazelle, giraffe and plains zebra) and domestic animal (cattle, sheep and goat) populations was studied in wildlife/livestock interface areas of Kenya. Serum samples were analyzed by competitive inhibition enzyme-linked immunosorbent assay (CI-ELISA), using a recombinant antigen (MSP-5) from Anaplasma marginale surface membrane. A monoclonal antibody, FC-16, was used as the primary antibody, while anti-mouse conjugated to horseradish peroxidase was used as the secondary antibody. The results indicate a high seroprevalence in both wildlife and livestock populations, in contrast to earlier reports from Kenya, which indicated a low seroprevalence. The differences are attributed to the accurate analytical method used (CI-ELISA), as compared with agglutination techniques, clinical signs and microscopy employed by the earlier workers.

The detection of non-RoTat 1.2 Trypanosoma evansi.

The majority of Trypanosoma evansi can be detected using diagnostic tests based on the variant surface glycoprotein (VSG) of Trypanosoma evansi Rode Trypanozoon antigen type (RoTat) 1.2. Exceptions are a number of T. evansi isolated in Kenya. To characterize T. evansi that are undetected by RoTat 1.2, we cloned and sequenced the VSG cDNA from T. evansi JN 2118Hu, an isolate devoid of the RoTat 1.2 VSG gene. A 273 bp DNA segment of the VSG gene was targeted in PCR amplification for the detection of non-RoTat 1.2 T. evansi. Genomic DNA samples from different trypanosomes were tested including 32 T. evansi, 10 Trypanosoma brucei, three Trypanosoma congolense, and one Trypanosoma vivax. Comparison was by PCR amplification of a 488 bp fragment of RoTat1.2 VSG gene. Results showed that the expected 273 bp amplification product was present in all five non-RoTat 1.2 T. evansi tested and was absent in all 27 RoTat 1.2-positive T. evansi tested. It was also absent in all other trypanosomes tested. The PCR test developed in this study is specific for non-RoTat 1.2 T. evansi.

PCR amplification of RoTat 1.2 VSG gene in Trypanosoma evansi isolates in Kenya.

A direct card agglutination test for Trypanosoma evansi, CATT/T. evansi based on the predominant variable antigen-type (pVAT) RoTat 1.2 was evaluated previously in the field in Isiolo District, Kenya. Sixteen out of 51 (31.4%) parasitologically positive camels were negative by the antibody detection test. In the present study, trypanosomes isolated from the camels were analysed in an attempt to determine the cause of the false negative results of CATT/T. evansi. A total of 20 field isolates comprised 16 stocks from camels that were negative by CATT/T. evansi, and 4 from CATT/T. evansi-positive camels. In addition, 15 known T. evansi and four T. brucei were used as reference. Purified DNA samples were tested using an established RoTat 1.2-based polymerase chain reaction (PCR) that yields a 488 bp product for the specific detection of T. evansi. Antibodies to RoTat 1.2 variant surface glycoprotein (VSG) were used in Western blotting to detect RoTat 1.2 VSG linear epitopes. Results of PCR and Western blot showed that the 16 stocks isolated from CATT/T. evansi-negative camels fell into three groups. In Group 1, both the RoTat 1.2 VSG gene and the VSG were absent in three stocks. In five trypanosome stocks in Group 2, the RoTat 1.2 VSG gene was detected, but Western blot was negative indicating absence of the expressed VSG. Five other stocks containing the RoTat 1.2 VSG gene were also in this group. The RoTat 1.2 VSG gene was detected and Western blot was positive in all four trypanosome stocks in Group 3. All four stocks from CATT/T. evansi-positive camels contained the RoTat 1.2 VSG gene and the expressed VSG. The reference T. evansi KETRI 2479 lacked the RoTat 1.2 VSG gene and there was no immune reactivity detected by Western blot. The rest of the reference T. evansi stocks examined contained the RoTat 1.2 VSG gene. All the four T. brucei samples examined were negative by PCR and Western blot. In conclusion, this study showed that the RoTat 1.2 VSG gene was absent from some T. evansi trypanosomes in Kenya.

Characterization of Anaplasma isolates from eland (Taurotragus oryx). Pathogenicity in cattle and sheep and DNA profiles analysis.

Two eland Anaplasma isolates, AnapE1, from Kenya, and AnapE2, from South Africa were characterised. Their characterization was based on their pathogenicity to intact and splenectomized cattle and sheep and also their DNA profiles. Their DNA profiles were analysed and compared to Anaplasma marginale, A. ovis and A. centrale after endonuclease restrictions and probing with Anaplasma DNA probes, AC5-12 and AC-1. The results of the pathogenicity trials showed AnapE1 to be similar to A. ovis and AnapE2 an isolate of A. marginale. On DNA profiles, AnapE1 was close to A. ovis, with differences that occur even in same Anaplasma species isolates from different locations. On the other hand, AnapE2, resembled one of the A. marginale isolates known to occur in South Africa. The DNA profiles correlated well with the pathogenicity results. It is concluded that elands are carriers of both A. marginale and A. ovis parasites and are therefore important reservoirs that need attention in epidemiology of anaplasmosis.

Pathogenesis of Trypanosoma (brucei) evansi in small east African goats.

Trypanosoma evansi is the cause of surra, a camel disease which is the most important single cause of economic losses in camel rearing areas. Sheep and goats herded with camels are the most likely hosts for T evansi. Upon intravenous infections goats developed erratic parasitaemia, lost weight and their packed cell volume dropped significantly (P < 0.001). Trypanosomes were demonstrated by direct microscopy in extravascular locations such as synovial, peritoneal and cerebrospinal fluids and also in lymph by subinoculations into mice. The carcases were emaciated and pale. Histologically there was lymphatic tissue hyperplasia, muscular atrophy and nephrotic changes. Two animals had necrotic foci in the liver, kidneys, lymph nodes, spleen and lungs and also bronchopneumonia. Histologically there was depopulation of lymphocytes in lymphatic tissues, destruction of hepatocytes in the liver with infiltration by inflammatory cells in the liver, lymph nodes, spleen and the kidneys.

The effects of experimental Trypanosoma (Trypanozoon) (brucei) evansi infection on the fertility of male goats.

The effects on the fertility of small East African male goats of intravenous infection with Trypanosoma (t) (b) evansi were studied. Six infected bucks developed erratic, low but persistent parasitaemia, the packed cell volume dropped gradually but significantly (p less than 0.001) and they became emanciated. Half of these bucks developed clinical orchitis. Two bucks died of the disease during the experiment. Semen from all the infected bucks deteriorated in quality and quantity and those with clinical orchitis became totally aspermic. Spermatozoal abnormalities and the number of dead spermatozoa rose significantly. Later in the disease, the testicles of the infected bucks atrophied. Histologically, the testicles from the infected animals became devoid of spermatozoa, the testicular blood vessels contained microthrombi and there was infiltration of inflammatory cells. Subsequently, diffuse calcification set in, with calcium deposits obliterating most of the seminiferous vesicles and ducts and also the epididymal ducts.