[Retinoblastoma in Kenya: survival and prognostic factors]. / Retinoblastom in Kenia : Überleben und prognostische Faktoren.

BACKGROUND: In industrialized nations a curative therapy of retinoblastoma can be achieved in a large number of patients due to timely diagnosis and therapy. In developing countries the survival rates are much lower and very little data have been published especially from Africa. OBJECTIVES: This study was performed to investigate the survival and prognostic factors of retinoblastoma patients admitted to Kenyatta National Hospital, the national referral hospital in Kenya. MATERIAL AND METHODS: In this study all records of patients admitted with retinoblastoma from January 2000 to December 2004 were reviewed. Demographic data, clinical presentation, intraoperative findings and histology reports were recorded and the patients or their relatives were contacted during follow-up to investigate the outcome and survival. RESULTS: Files of 160 patients (86 males and 74 females) were retrieved for this study. Data on 3-year survival could be acquired from 105 patients and the cumulative 3-year survival rate was 26.6 %. Factors significantly influencing survival were age at presentation less than 12 months, early disease at presentation (leukocoria only), no extraocular growth and total delay of management ≤ 5 months. Proptosis and tumor recurrence were associated with a 3-year mortality of 100 %. CONCLUSION: The main reasons for poor outcome were late presentation and recurrent disease after initial treatment elsewhere, extraocular growth and delay between initial presentation and treatment. Awareness of the public and of healthcare workers should be increased in order to reduce the time delay until diagnosis and treatment.

Prevalence, pathology and risk factors for coccidiosis in domestic rabbits (Oryctolagus cuniculus) in selected regions in Kenya.

BACKGROUND: The potential for rabbit production in Kenya is high. However, high morbidity and mortality of domestic rabbits were reported. OBJECTIVE: The aim of the study was to determine the pathology, prevalence and the predisposing factors to coccidiosis in domestic rabbits in selected regions in Kenya. ANIMALS AND METHODS: A total of 61 farms keeping rabbits in six different counties were visited in the survey. A total of 2680 live rabbits were examined and 61 rabbits and 302 fecal samples were randomly collected from the farms and examined for coccidian oocysts by ante-mortem and post-mortem methods. The predisposing factors to coccidiosis were assessed through questionnaires and direct observation. Chi square (χ(2)) statistics was used with P values < 0.05 considered statistically significant. RESULTS: Of the 302 fecal samples, 85% (P < 0.001) contained coccidian oocysts and 2% harbored nematode eggs (Passalurus ambiguous). The overall prevalence of Eimeria spp. infestation was 85.1% in the study area and 90.2% in the individual rabbits, while prevalence of intestinal coccidiosis and hepatic coccidiosis was 29.5% and 11.5%, respectively. Higher counts of coccidian oocysts per gram of feces were recovered in weaners than in growers and adults rabbits (P < 0.001), rabbits that were kept in high density group housing (P < 0.05) and housing with more than two tiers. CONCLUSION: This study identified group housing of rabbits of different ages and inadequate control of concurrent infections as the major risk factors associated with coccidiosis in domestic rabbits in Kenya.

Effects of dehydration and heat stress on food intake and dry matter digestibility in East African ruminants.

Comparative investigations were made between wild and domestic ruminants from arid and semi-arid regions and those species from non-arid areas in an attempt to evaluate the adaptations of these ruminants in terms of the effects of heat stress and dehydration on food intake and digestibility. The effect of (a) an intermittent heat load (a daily light cycle of 12 h at 22 degrees C and 12 h at 40 degrees C) compared to 22 degrees C throughout the day and (b) dehydration level of 15% weight loss, with and without the heat load, on the intake and digestibility of a poor quality hay was investigated in the Grant's gazelle, Oryx, the domestic Turkana goats, fat-tailed sheep, zebu cattle, Thomson's gazelle and wildebeest. The intermittent heat load with water available ad libitum depressed the food intake of zebu cattle and Turkana goats by more than 40%. It had no significant effect on the food intake of the other species. The Thomson's and Grants gazelle, oryx, wildebeest and fat-tailed sheep appear well adapted to withstanding a periodic heat load. Dehydration at 22 degrees C caused a marked depression on food intake of all the species investigated. Dehydration together with a heat load caused no further reduction in the food intake by the Grants's gazelle, oryx, and goats but it did cause a further reduction in the intake in the other species. The small non-domestic ruminants (i.e. Grant's and Thomson's gazelle) appear much more digestive efficient than any of their domestic counterpart.