Male philopatry,extra-pack copulations and inbreeding avoidance in Ethiopian wolves (Canis simensis)

Monogamous pairings have been regarded as the fundamental social unit in all canid species, including those living in packs. In Ethiopian wolves, however, habitat saturation limits dispersal, which raises the question of whether they avoid inbreeding and, if so, by what mechanism. In two study areas Ethiopian wolf packs had stable memberships. Each pack comprised two to eight adult males, one to three adult females, including a clear-cut dominant individual of each sex, together with one to six yearlings and up to six pups (n = 9 packs). Males remained in their natal packs, apparently throughout their lives. Some females also failed to disperse while others dispersed in their second or third year and became floaters. Dominant females monopolized breeding, and were succeeded either by their most dominant daughters (three cases) or by floaters (two cases). In the former case there is potential for incest; however, 70% of 30 copulations observed were between the dominant female of one pack and a male from an adjoining pack. In Ethiopian wolves, under conditions where dispersal is constrained and the potential for inbreeding is high, extra-pack matings (and associated multiple paternity) result in outbreeding. We raise the possibility that extra-pair copulations may be widespread in canid societies and that the monogamy supposedly fundamental to the family may be more sociological than genetic. Received: 15 October 1994/Accepted after revision: 9 December 1995     

Speciation and antimicrobial resistance of Enterococci isolated from recreational beaches in Malaysia

We report the first study on the occurrence of antibiotic-resistant enterococci in coastal bathing waters in Malaysia. One hundred and sixty-five enterococci isolates recovered from two popular recreational beaches in Malaysia were speciated and screened for antibiotic resistance to a total of eight antibiotics. Prevalence of Enterococcus faecalis and Enterococcus faecium was highest in both beaches. E. faecalis/E. faecium ratio was 0.384:1 and 0.375:1, respectively, for isolates from Port Dickson (PD) and Bagan Lalang (BL). Analysis of Fisher’s exact test showed that association of prevalence of E. faecalis and E. faecium with considered locations was not statistically significant (p?<?0.05). Chi-square test revealed significant differences (χ ²?=?82.630, df?=?20, p?<?0.001) in the frequency of occurrence of enterococci isolates from the considered sites. Resistance was highest to nalidixic acid (94.84 %) and least for chloramphenicol (8.38 %). One-way ANOVA using Tukey–Kramer multiple comparison test showed that resistance to ampicillin was higher in PD beach isolates than BL isolates and the difference was extremely statistically significant (p?<?0.0001). Frequency of occurrence of multiple antibiotic resistance (MAR) isolates were higher for PD beach water (64.29 %) as compared to BL beach water (13.51 %), while MAR indices ranged between 0.198 and 0.48. The results suggest that samples from Port Dickson may contain MAR bacteria and that this could be due to high-risk faecal contamination from sewage discharge pipes that drain into the sea water.     

High-level aminoglycoside resistance and virulence characteristics among Enterococci isolated from recreational beaches in Malaysia

We report the first study on the occurrence of high-level aminoglycoside-resistant (HLAR) Enterococci in coastal bathing waters and beach sand in Malaysia. None of the encountered isolates were resistant to high levels of gentamicin (500 μg/mL). However, high-level resistance to kanamycin (2,000 μg/mL) was observed in 14.2 % of tested isolates, the highest proportions observed being among beach sand isolates. High-level resistance to kanamycin was higher among Enterococcus faecalis and Enterococcus faecium than Enterococcus spp. Chi-square analysis showed no significant association between responses to tested antibiotics and the species allocation or source of isolation of all tested Enterococci. The species classification of encountered Enterococci resistance to vancomycin was highest among Enterococcus spp. (5.89 %) followed by E. faecium (4.785) and least among E. faecalis. A total of 160 isolates were also tested for virulence characteristics. On the whole, caseinase production was profoundly highest (15.01 %) while the least prevalent virulence characteristic observed among tested beach Enterococci was haemolysis of rabbit blood (3.65 %). A strong association was observed between the source of isolation and responses for each of caseinase (C?=?0.47, V?=?0.53) and slime (C?=?0.50, V?=?0.58) assays. Analysis of obtained spearman’s coefficient showed a strong correlation between caseinase and each of the slime production (p?=?0.04), gelatinase (p?=?0.0035) and haemolytic activity on horse blood (p?=?0.004), respectively. Suggestively, these are the main virulent characteristics of the studied beach Enterococci. Our findings suggest that recreational beaches may contribute to the dissemination of Enterococci with HLAR and virulence characteristics.     

Combating dye pollution using cocoa pod husks: a sustainable approach

The adsorptive potential of activated carbon prepared by chemical activation of Cocoa pod husk (CPHAA) to remove Congo red (CR) dye from its aqueous solution was investigated in this study. CPHAA was characterised using Energy Dispersive X-Ray, Scanning Electron Micrograph and Fourier Transform Infrared Spectroscopy techniques. The effects of contact time, initial dye concentration, pH and solution temperature were studied. Equilibrium data were fitted to Langmuir, Freundlich, Temkin and Dubinin–Radushkevich isotherm models. The equilibrium data were best represented by Langmuir isotherm model, with maximum monolayer adsorption capacity of 43.67 mg/g. The kinetic data were fitted to Pseudo-first-order, Pseudo-second-order, Elovich and Intraparticle diffusion models; the pseudo-second-order kinetic model provided the best correlation. Thermodynamic parameters such as standard enthalpy (ΔH^o), standard entropy (ΔS^o) and standard free energy (ΔG^o) were evaluated. The thermodynamic study showed that the process is endothermic, spontaneous and feasible. The mean free energy of adsorption shows that the mechanism is by physisorption. CPHAA was found to be an effective adsorbent for the removal of CR dye from aqueous solution.