Healthcare workers (HCWs) reporting no history of varicella frequently receive varicella vaccination (vOka) if they test varicella-zoster virus (VZV) immunoglobulin G (IgG) negative. In this study, the utilities of VZV-IgG time-resolved fluorescence immunoassay (VZV-TRFIA) and a commercial VZV-IgG purified glycoprotein enzyme immunoassay (gpEIA) currently used in England for confirming VZV immunity have been compared to the fluorescent-antibody-to-membrane-antigen assay (FAMA). A total of 110 HCWs received two doses of vOka vaccine spaced 6 weeks apart and sera collected pre-vaccination (n = 100), at 6 weeks post-completion of vaccination (n = 86) and at 12–18 months follow-up (n = 73) were analysed. Pre-vaccination, by FAMA, 61·0% sera were VZV IgG negative, and compared to FAMA the sensitivities of VZV-TRFIA and gpEIA were 74·4% [95% confidence interval (CI) 57·9–87·0] and 46·2% (95% CI 30·1–62·8), respectively. Post-completion of vaccination the seroconversion rate by FAMA was 93·7% compared to rates of 95·8% and 70·8% determined by VZV-TRFIA and gpEIA, respectively. At 12–18 months follow-up seropositivity rates by FAMA, VZV-TRFIA and gpEIA were 78·1%, 74·0% and 47·9%, respectively. Compared to FAMA the sensitivities of VZV-TRFIA and gpEIA for measuring VZV IgG following vaccination were 96·4% (95% CI 91·7–98·8) and 74·6% (95% CI 66·5–81·6), respectively. Using both FAMA and VZV-TRFIA to identify healthy adult VZV susceptibles and measure seroconversion showed that vOka vaccination of HCWs is highly immunogenic.

The immediate postweaning period in pigs is often characterised by a reduced and variable food intake and poor growth and development, reducing lifetime performance. At present the effects of the postweaning growth check are reduced by the use of antibiotic growth promoters (AGPs), copper sulphate and zinc oxide to enhance the efficiency of feed conversion and hence maximise nutrient capture. However from January 2006 the routine use of in feed AGPs is to be banned and, due to concern over environmental pollution, levels of inclusion of heavy metals are likely to be further reduced. Weaning pigs from the sow at an older age, when their digestive systems are more mature, has been suggested as an approach to reduce the potential negative effect of the AGP ban on the national herd. The objective of the AGEWEAN programme of research is to investigate the effects of weaning age (4, 6 and 8 weeks) in both an indoor and outdoor lactation environment on biological and economic efficiency of a production system where diets contain no AGPs and lower levels of copper (<25ppm added) and zinc (<100ppm added).

Approximately 5% of pigs slaughtered in the UK have been tail-bitten, leading to welfare and production issues. Tail biting is sporadic and not all pigs tail bite. The aim of this study was to identify factors that are common in pigs that perform tail-biting behaviour, and that might be used in a predictive way to identify such animals.

The behaviour of 159 pigs was observed in the post-weaning period. Pigs were weaned at 4 weeks of age. In the week prior to weaning and at 6 weeks of age each pig was individually tested in a tail chew test (tail chew test 1 and 2, respectively). The tail chew test involved recording the pig's behaviour directed towards two ropes, one of which had been soaked in saline solution and the other not. The production performance of the pigs was recorded from birth to 7 weeks of age. Time spent performing tail-biting behaviour correlated positively with time in contact with the rope in tail chew test 2 (r = 0·224, P < 0·05), and time spent ear biting correlated positively with time spent in rope directed behaviour in tail chew test 1 (r = 0·248, P < 0·01). Pigs that spent as much as 1·5% of their time of more performing tail-biting behaviour were lighter at weaning (26 days) and tended to be lighter at 7 weeks of age compared with pigs that spent less than 1·5% of their time performing tail-biting behaviour (weaning weight: ≥1·5% tail biting 8·96 kg, <1·5% tail biting 9·67 kg, P < 0·05; 7-week weight: ≥1·5% tail biting 15·75 kg, <1·5% tail biting 17·09 kg, P < 0·08). There was no significant difference in birth weight between pigs that spent ≥ or <1·5% of their time performing tail-biting behaviour. Pigs that spent 1·5% of their time or more performing tail-biting behaviour showed significantly lower growth rates between birth and weaning (≥1·5% tail biting 260 g/day, <1·5% tail biting 285 g/day, P < 0·05) but not between weaning and 7 weeks of age (≥1·5% tail biting 343 g/day, <1·5% tail biting 365 g/day, P > 0·05).

The results suggest that pigs that tail bite have some nutritional deficiency that results in performance of foraging behaviour that is expressed in intensive housing as ear/tail biting.

The development of adverse behaviour in group–housed growing/ finishing pigs with intact tails was studied in a straw–flow housing system and in a part–slatted system with a commercial enrichment object. Food intake, body weight and behaviour were monitored over the finishing period, with tail biting outbreaks defined as an occasion where three or more pigs within a group had freshly damaged tails and tail biting behaviour was ongoing. Data from the two systems were analysed to identify tail–biting outbreaks and behavioural changes over time. Levels of pig manipulation were higher in the part–slatted system. Over time, pigs in both systems showed reduced interest in the enrichment provided, but not in each other. Despite the presence of the enrichment device, tail biting occurred in all groups in the part–slatted system, but only 1/12 groups in the straw–flow system. The amount of time occupied by manipulation of the enrichment provided was very significantly higher for straw than for the commercial object. Better design of enrichment strategies is therefore needed and should be based on species–relevant requirements.

Recent research suggests that the genetic makeup of a pig may contribute to the expression of tail biting (Breuer et al., 2002). To date there has been little investigation into the genetics of tail biting. A significant population of tail biters was found at a commercial pig breeding farm at which an experiment on the genetic basis of the expression of harmful social behaviour was being performed. As pedigree data for each pig on the farm were available, the opportunity was taken to investigate the heritability of tail biting by recording the perpetrators of clinical tail biting.

We have studied the influence of an epitaxial silicide layer on the diffusion of B and Sb in silicon. B and Sb doping superlattices have been grown by molecular beam epitaxy. They were then covered with a 20 nm thick CoSi2 layer. Test samples were also grown without silicide. Samples were oxidized at various temperatures ranging from 800°C to 1200°C for times that ensured sufficient broadening of the spikes. Another set of samples was annealed at the same times and temperatures in N2. Dopant depth profiles were measured before and after diffusion by secondary ion mass spectrometry (SIMS). At the test samples we observed thermal diffusion of B and Sb, oxidation enhanced diffusion of B and oxidation retarded diffusion of Sb, all in accordance with the literature. In contrast to this, oxidized silicide capped samples showed a retardation of B diffusion by a factor of 2 - 10 as compared to thermal diffusivity and an enhancement of Sb diffusion by a factor of 1 - 2.

Carbon films deposited by a modified dc cathodic arc technique were characterized by several analytical methods. The coatings consist of two constituents originating from process characteristics of the technique applied. Small fragments of graphite are embedded in a matrix material of an amorphous structure with diamond-like short-range order. The coatings exhibit friction and wear reducing properties.