Results presented here demonstrate that both HIV-1 exposure and HIV-1 infection are associated with increased prevalence of SMA during acute P. falciparum infection, independent of parasite density.

The introduction of invasive Nile tilapia (Oreochromis niloticus), and the rapacious predator Nile perch (Lates niloticus), into Lake Victoria resulted in a decline in population sizes, genetic diversity and even extirpation of native species which were previously the mainstay of local fisheries. However, remnant populations of native fish species, including tilapia, still persist in satellite lakes around Lake Victoria where they may coexist with O. niloticus. In this study we assessed population genetic structure, diversity, and integrity of the native critically endangered Singidia tilapia (O. esculentus) in its refugial populations in the Yala swamp, Kenya, and contrasted this diversity with populations of the invasive tilapia O. niloticus in satellite lakes (Kanyaboli, Namboyo and Sare) and Lake Victoria. Based on mtDNA control region sequences and eight nuclear microsatellite loci, we did not detect any mtDNA introgression between the native and the invasive species in Lakes Kanyaboli and Namboyo, but did find low levels of nuclear admixture, primarily from O. niloticus to O. esculentus. Some genetic signal of O. esculentus in O. niloticus was found in Lake Sare, where O. esculentus is not found, suggesting it has recently been extirpated by the O. niloticus invasion. In both species, populations in the satellite lakes are significantly genetically isolated from each other, with private mtDNA haplotypes and microsatellite alleles. For O. niloticus, genetic diversity in satellite lakes was similar to that found in Lake Victoria. Our data imply a low frequency of immigration exchange between the two populations of O. esculentus and we suggest that the populations of this endangered species and important fisheries resource should be conserved separately in Lakes Kanyaboli and Namboyo and with high priority.

Background: Human infections caused by pathogens transmitted from fish are quite common. The aim of this study was to isolate enteric pathogenic bacteria from fish that might be transmitted to humans after the handling or consumption of such fish. Methodology: One hundred and twenty Nile tilapia fish harvested using various fishing methods were collected from fishermen in five fish landing beaches within Winam Gulf and disinfected externally using 70% ethyl alcohol for 2 minutes then washed three times with autoclaved distilled water. Isolation of Salmonella and Shigella species from fish samples was performed using standard bacteriological procedures. Five milliliters of each fish tissue slurry was microbiologically analyzed for any Enterobacteriaceae. Twelve Nile tilapia collected from three open-air markets were analyzed for Enterobacteriaceae comparison as controls. Identification of Salmonella by using housekeeping genes and species-specific primers was performed. Results: Among 120 Nile tilapia, 63 (52.5%) were infected with Enterobacteriaceae. Out of these, 25 (39.7%) were Shigella spp, 9 (14.3%) Salmonella typhimurium, 7 (11.1%) S. typhi, 4 (6.3%) S. enteritidis, 16 (25.4%) Escherichia coli, 1 (1.6%) Proteus spp. and Enterobacter aerogenes respectively. Ten fish collected from open-air markets yielded E. coli (50%), S. typhimurium (20%), S. paratyphi (10%) and S. typhi (20%). Conclusion: Nile tilapia within Winam Gulf are infected by human enteric pathogens. Shigella spp., Salmonella and E. coli were the most frequently isolated, an indication that the beaches may be contaminated by untreated municipal sewage, runoff, and storm-water. S. typhimurium, S. typhi and S. enteritidis were the most common Salmonella isolates.

Trypanosomiasis induces histological testicular degenerative changes leading to suppression of spermatogenesis in goats and laboratory animals. We present evidence associating these changes with trypanosome-induced endocrine dysfunction. Toggenburg goats were infected with approximately 100,000 trypanosomes. They were bled every 2 days, and the plasma testosterone was analyzed by radioimmunoassay. Testes were perfused with and fixed in Bouin's fixative for histological evaluation. The infected plasma samples showed depressed testosterone levels with episodic peaks reduced in both amplitude and frequency. Histological characteristics of the testicular and epididymal tissues revealed aspermic tubules and epididymides and desquamation of the tubular germinal epithelia. These testicular degenerative changes may be partly due to the depressed plasma testosterone levels.

Fish farmers have a tendency of employing high stocking density (HSD) as a means of increasing productivity. However, HSD is a chronic stressor that is likely to lower profitability of fish farming if not implemented properly. HSD induces stress which in turn elevates sequentially the levels of plasma cortisol and glucose. The resultant glucose is distributed to various tissues by glucose transporter protein (GLUTs) to restore normalcy. GLUT 1, transmembrane protein found in erythrocytes, is responsible for import and export of glucose in red blood cells. However, knowledge on how chronic stress impact glucose and GLUT 1 protein in fish subjected to HSD is still unclear. In this study, effect of HSD on the expression of GLUT 1 in Nile tilapia was investigated in an attempt to elucidate the role of GLUT 1 in glucose metabolism during chronic stress. Fish were reared for 4 weeks at 1.5 and 4.5 kg/m 3 for low stocking density (LSD) and HSD, respectively. Four physiological parameters were determined from the blood samples obtained from fish at the end of experiment. At p \ 0.05, there were significant differences between fish reared at HSD and LSD in plasma cortisol level (72.1 ± 5.9 ng/ml and 37.5 ± 4.6 ng/ml); blood glucose level (136.00 ± 1.3 mg/dL and 70.2 ± 1.0 mg/dL); erythrocytes count (7.2 ± 0.5 9 106 mm -3 and 2.1 ± 0.4 9 106 mm -3 ); and plasma GLUT 1 level (1.40 ± 0.17 rbi and 0.81 ± 0.07 rbi), respectively. HSD induced elevation of plasma cortisol level, blood glucose level, erythrocytes count and GLUT 1 level. These elevated physiological factors and particularly GLUT 1 can be used as a cellular stress biomarker in fish farming and aquaculture.