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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 (x 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.

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Combining ability of inbred lines is important information in maize hybrid breeding programs incorporating materials from various germplasm sources. This study was conducted with germplasm varying in their maize streak virus (MSV) reaction, genetic, and geographic origin. In a half diallel cross of six parents, general and specific combining abilities were determined for grain yield, days to silking, ear height and MSV disease resistance. The grain yields of the single crosses were significantly higher from those of the hybrid checks, H614 and H513, which are popular varieties. The importance of both GCA (53%) and SCA (47%) for grain yield was observed, but a preponderance of GCA existed for days to silking, ear height, and MSV disease resistance. The best general combiners for grain yield and MSV resistance were CML197 (0.92, p<0.001) and C92 (-0.61 p<0.001) respectively. The prediction of hybrid performance for grain yield and MSV resistance could be based on GCA alone, but this should be within specific niches since GCA interacted highly with environments.