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Studies were undertaken to determine if florfenicol, an antimicrobial agent structurally similar to chloramphenicol, could be used as an effective broad spectrum antibiotic for the treatment of bacterial infections in primates. Florfenicol was developed as an injectable antibiotic for use in cattle on an every other day dosing schedule. Its broad spectrum activity, long duration of action following i.m. administration, and its safety as compared with chloramphenicol made it an attractive antibiotic for use in non-human primates. Previous studies had shown that florfenicol is effective against common primate pathogens such as Salmonella, Klebsiella, Escherichia coli, Bordetella bronchiseptica, Streptococcus pneumoniae, Staphylococcus spp., and Yersinia pseudotuberculosis. We performed experiments on a total of 15 macaques. The animals were given florfenicol at 50 mg/kg i.m. and blood samples taken at various time points. Serum was evaluated for florfenicol absorption. Necropsies were also performed to determine if major organs were affected and to determine the effects of i.m. injection of florfenicol. We determined that florfenicol given every 48 hours in rhesus macaques results in blood levels that were acceptable for therapeutic use. The effect on muscle tissue of i.m. injection was similar to ketamine and normal saline. There were no gross lesions observed and no changes with tissues submitted for histology. Our work shows that with further studies, florfenicol may be useful when injectable antibiotic therapy is required in non-human primates.

The Northern Ireland Credit Accumulation and Transfer Scheme encompasses all levels from introductory to doctoral. It was designed to facilitate the progression of learners through both the Further and Higher Education structures in Northern Ireland and has provided the model for developments elsewhere. Part of its development included a consultative procedure that involved curriculum specialists liaising with a wide range of practitioners to identify strengths and problematic areas within the scheme. The consultation found that, at the time (1998), practitioner awareness of CATS schemes was generally poor. Most teachers of lower level courses felt that the scheme in general would add value to their courses since it would place them within a hierarchical framework and indicate to their students clear forward progression routes. Many teachers of multilevel courses (in particular degrees) felt that attempting to define levels within a course would result in a loss of teacher autonomy and a reduction in the flexibility with which courses could be offered. Many interviewees stressed the sequential nature of their subject’s structure and the perception that this caused problems for student progression through a system of levels based on generic descriptors. It is concluded that although there was broad practitioner support for NICATS, many of its potential benefits will only be realized after substantial staff development. When implemented, it should result not only in a more transparent description of courses but also substantial development in the delivery of curricula and the assessment of student learning.

Freshly caught samples of slugs were maintained at constant temperature and humidity but at day lengths (from 5 h 50 min to 16 h darkness) appropriate to the time of year at which they were collected. The duration of their feeding and crawling activities as well the total time spent active was recorded by time-lapse cinematography. Total activity was significantly higher in autumn and spring than in summer and winter. The activity period was symmetrically disposed about the midpoint of the dark period except for two samples in autumn. At scotoperiods longer than about 12 h, activity onset was delayed relative to the start of the dark period and activity cessation was advanced relative to the end of the period, resulting in the short duration of activity seen in winter. At scotoperiods of less than 12 h the duration of activity was relatively independent of scotoperiod. In spring the total time spent crawling was composed of relatively few bouts of long duration whereas in the autumn the number of bouts was greater and their duration shorter. The winter was characterized by slugs making single journeys to and from the food. While emerged these slugs stayed in close association with the food but not necessarily feeding on it. These data are discussed in terms of comparisons with homoiothermic nocturnal animals. It is concluded that seasonal responses in poikilothermic animals are likely to be limited by the hazards of winter even when such animals are maintained in apparently non-limiting conditions.

Euglandina was collected over a three-year period in four habitat types in Mauritius. Smaller collections were also made in Reunion and Rodrigues. The areas in which the Euglandina were collected were simultaneously sampled for potential prey species. Identification of the stomach contents and comparison with the available prey shows that most prey are eaten whole and that native species are eaten in greater numbers that would be expected form a consideration of their numbers in the habital. Achatina spp., which Euglandina was originally introduced to control, was not positively identified in the diet. Even if all unidentified prey fragments were form Achatina then this would form less than 5% of the total number of items in the stomachs. Habital destruction, together with predation by Euglandina, appear to be major contributors to the extinctions of native Mauritian snails. The conservation of primary forests, into which Euglandina has not penetratd, is suggested as the most effective way to save the remaining endemic ground-dwelling snails form extinction. These results add further emphasis to the importance of preventing introductions of Euglandina to areas with native snail faunas, and show clearly that this predator is not a successful control agent for Achatina.

The mucus-producing glands of the tropical slug Veronicella floridana Leidy were examined histochemically. The bulk of the dorsal mucus is a carboxylated mucopolysaccharide produced by deeply embedded gland cells which contribute to inflated common ducts. Little mucus is apparent on the dorsal surface of an unirritated slug, giving the dorsal aspect of the animal a dry appearance. Measurements of the rate of water loss of whole animals indicate that water is lost significantly more slowly than from the equivalent area of water. The foot possesses regular transverse ridges and the pedal mucus is produced largely by a set of gland cells associated with each ridge. This mucus is a mixture of mucopolysaccharides and protein. The suprapedal gland which also contributes to the pedal mucus is extremely small and produces a weakly acidic and neutral mucopolysaccharide and a protein. There is no specialization in the leading edge of the foot and no Semper's organ. The cleft between the foot and the body is unciliated and bears few specialized gland cells. Compared with the mucus produced by Limax pseudoflavus, the pedal mucus of Veronicella is of comparable function and composition though produced by glands of different derivations. The dorsal mucus is histochemically different from that of Limax though similar in physical appearance. Whilst the dorsal mucus of Limax is freely distributed over exposed surfaces, that of Veronicella is held in reserve in inflated ducts resulting in a dry leathery appearance and a depressed rate of water loss.

The phase changes in the activity rhythm of the pulmonate slug Limax pseudoflavus caused by light pulses (30 min, 10,000 lux) in otherwise dark conditions were recorded using time lapse cinematography and tipping aktographs. From the timing of the pulse relative to an individual activity cycle a phase response curve was constructed. Phase delays occurred when the pulse was administered in the early subjective night and subjective day, phase advances were recorded during the mid and late subjective night. The effects of two pulses (30 min, 10,000 lux) forming symmetric and asymmetric skeleton photoperiods were also recorded and related to the phase response curve. Both stable and unstable entrained states were found, the condition being dependent upon the relative timing of the two pulses and the previous activity onset. It was also shown that there was a time lag between the light pulse and its expressed phase setting effect. Thus phase setting is not instantaneous as with some insects.

The gross anatomy and histochemistry of the mucus-producing glands of Limax pseudoflavus Evans were investigated. The body mucus can be divided into three areas. The dorsal body surface is covered with a sulphated acid mucopolysaccharide/protein mixture secreted largely by five cell types. The pedal mucus is a mixture of neutral mucopolysaccharide from the suprapedal gland. The dorsal and pedal mucus sheets are separated by the peripodal groove whose cells secrete a weakly acid mucus. The duct of the suprapedal gland, the epidermis around the pneumostome, the ventral surface of the peripodal groove and the centre of the underside of the foot are ciliated. The dorsal and pedal mucus remain stationary relative to the body and the substrate respectively and the only rejection currents seen in the mucus are around the pneumostome. It is suggested that the pedal mucus is formed by the mixture of the products of the suprapedal gland and the mucoprotein secreting gland in the leading edge of the foot, thus producing a mucus suitable for locomotion. Many areas of the animal (e.g. the head, pneumostome, sole and the leading edge of the foot) are capable of producing both a fluid (neutral or weakly acid) and a viscous (acid) mucus. It is postulated that such an arrangement allows for both adhesion and lubrication at different times.

At high chloride concentrations (2 mol dm–3) the oxidation of chloride to chlorine by Ce4+ ions, i.e. 2Ce4++ 2Cl–→ 2Ce3++ Cl2 was found to be catalysed by an activated form of ruthenium dioxide hydrate (RuO2·x′H2O*). A kinetic study of this process revealed that the disappearance of Ce4+ ions was first-order with respect to the concentrations of Ce4+ and redox catalyst, and zero-order with respect to the concentrations of chloride and Ce3+ ions. On reducing the chloride concentrations below a threshold value, ca. 0.2 mol dm–3, the Cl2 and O2 yields were found to decrease (from 98 to 0%) and increase (from 0 to 95%), respectively, although the rate of disappearance of the Ce4+ ions remained almost unaffected. At [Cl–] < 0.01 mol dm–3 only O2 evolution was observed. These results were interpreted using an electrochemical model in which the catalyst particles were assumed to be acting as microelectrodes and the current density due to chlorine evolution was proportional to the square of the chloride concentration. In addition to activated ruthenium dioxide hydrate several other materials were tested successfully for catalytic activity, including non-activated ruthenium dioxide hydrate (RuO2·xH2O). However, unlike RuO2·x′H2O* these other materials did not catalyse the oxidation of water to oxygen by Ce4+ ions in the absence of brine.