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Paenibacillus larvae is a highly contagious and often lethal widely distributed pathogen of honeybees, Apis mellifera but has not been reported in eastern Africa to date. We investigated the presence of P. larvae in the eastern and western highland agro-ecological zones of Uganda by collecting brood and honey samples from 67 honeybee colonies in two sampling occasions and cultivated them for P. larvae. Also, 8 honeys imported and locally retailed in Uganda were sampled and cultivated for P. larvae. Our aim was to establish the presence and distribution of P. larvae in honeybee populations in the two highland agro-ecological zones of Uganda and to determine if honeys that were locally retailed contained this lethal pathogen. One honeybee colony without clinical symptoms for P. larvae in an apiary located in a protected area of the western highlands of Uganda was found positive for P. larvae. The strain of this P. larvae was genotyped and found to be ERIC I. In order to compare its virulence with P. larvae reference strains, in vitro infection experiments were conducted with carniolan honeybee larvae from the research laboratory at Ghent University, Belgium. The results show that the virulence of the P. larvae strain found in Uganda was at least equally high. The epidemiological implication of the presence of P. larvae in a protected area is discussed. [ABSTRACT FROM AUTHOR]

The amount of plant foods eaten and sexual differences in food intake among chimpanzees in Kibale Forest was investigated between July 2007 and January 2008. Continuous focal animal sampling was used to collect data on the diet, number, and duration of feeding bouts of 18 individuals of the Kanyawara chimpanzee community. Chimpanzees utilized 42 plant species for fruits, leaves, and piths. Among plant parts eaten, fruits contributed the greatest percentage of fresh weight (18) in the diets compared to leaves (5.1) and piths (3.6). The duration of feeding bouts varied, ranging from 1.5 to 45.8 minutes. When Mimusops bagshawei fruits were eaten, the numbers of feeding bouts per chimpanzee per day were high compared to when they were not. While our study agrees with previous studies that females spend more time feeding per day, it shows that the long feeding time among females does not translate to increased food weight. We suggest that the social role of females in taking care of the young and their attention being taken up by this role while feeding and fears associated with male presence is the reason for long feeding time among females. [ABSTRACT FROM AUTHOR]

Background: Malaria is often persistent in communities surrounded by mosquito breeding habitats. Anopheles gambiae sensu lato exploit a variety of aquatic habitats, but the biotic determinants of its preferences are poorly understood. This study aimed to identify and quantify macroinvertebrates in different habitat types with determined water physico-chemical parameters to establish those preferred by An. gambiae s.l. larvae as well as their predators and competitors. Methods: A field survey was conducted in Kibuye and Kayonjo villages located in the vicinity of the River Sezibwa, north-eastern Uganda to identify Anopheline larval habitats shared by aquatic insects. Habitats were geo-recorded and as streams, ponds, temporary pools and roadside ditches. From October to December 2017, random microhabitats/quadrats were selected from each habitat type, their water physico-chemical parameters (electrical conductivity, total dissolved solids, temperature and pH) were measured, and they were sampled for macroinvertebrates using standard dippers. All collected arthropod macroinvertebrates were then morphologically identified to family level and enumerated. Results: Principal component analysis showed that the four larval habitat types were characterized by distinct physico-chemical parameter profiles. Ponds and streams had the highest number and diversity of macroinvertebrate insect taxa and sustained few An. gambiae s.l. larvae. Anopheles gambiae s.l. were more common in roadside ditches and particularly abundant in temporary pools which it commonly shared with Dytiscidae (predaceous diving beetles) and Culex spp. Cluster correlation analysis conducted on the abundance of these taxa within quadrats suggested that An. gambiae s.l. and Dytiscidae have the most similar patterns of microhabitat use, followed by Cybaeidae (water spiders). Whilst Culex spp. co-occurred with An. gambiae s.l. in some habitats, there was only partial niche overlap and no clear evidence of competition between the two mosquito taxa. Conclusions: Ponds and streams are habitats that host the largest diversity and abundance of aquatic insect taxa. Anopheles gambiae s.l. larvae distinctively preferred temporary pools and roadside ditches, where they were exposed to few predators and no apparent competition by Culex spp. Further studies should aim to test the impact of Dytiscidae and Cybaeidae on An. gambiae s.l. dynamics experimentally. [ABSTRACT FROM AUTHOR]

Recent evidence has shown that improved light traps comprising modified drums and light emitting diode bulbs are more efficient and safer in mass trapping of wild swarms of Ruspolia differens compared to mercury light traps with open-ended drums commonly used in Uganda. However, financial analysis of the improved traps had not yet been conducted prior to this study. Here, we carried out a cost–benefit analysis of the improved trap compared to the existing trapping technique. A pre-tested questionnaire was used to collect data on the demographic characteristics, revenue, capital expenditures and operating costs of the current trapping method from 30 commercial R. differens trappers in Masaka Uganda. The costs and revenue from the improved trap were collected basing on the market price and estimates for the 30 trappers. Net present value (NPV), benefit–cost ratio (BCR) and payback period were computed for the improved and current method and compared using an independent sample t-test. The results revealed that the improved trapping technique was more profitable than the current technique. Moreover, high costs of electricity and harmful non-target insects, especially the Nairobi fly (Paederus sp) which causes dermatitis were other difficulties associated with the current trapping technique. We, therefore, recommend adoption of the improved R. differens trapping technique as a more profitable alternative to the current technique. [ABSTRACT FROM AUTHOR]