Prolonged periods of stress have been associated with impaired immune function; the experiment reported here investigates a potential link between level of metabolic load and immune function in lactating dairy cattle. A group of 111 Holstein-Friesian dairy cows was used. The cows belonged to one of two genetic lines: a selection line (S) with high genetic merit for fat plus protein yield and an unselected control line (C). The cows were offered one of two silage-based total mixed diets containing either 200 g (LC) or 450 g (HC) of concentrate per kg dry matter. Combination of genetic selection and food gave four groups: S-LC, S-HC, C-LC and C-HC. All cows were inoculated with a live attenuated BHV-1 vaccine soon after parturition and the primary antibody response in whey monitored. The number of BHV-1 antibody positive cows was not significantly different between the four groups; but, the initial antibody response was lower in cows of high genetic merit which were given a low concentrate diet. Statistical analysis demonstrated that the contribution of diet to this effect was highly significant. One year later, again after parturition, the experiment was repeated, this time using serum as the test sample. The average antibody response of the BHV-1 antibody positive cows was not significantly different between the four groups but the number of antibody positive cows was group-dependent. In conclusion, diet type but not genetic merit for high fat plus protein yield made a highly significant contribution to the antibody response of dairy cows to BHV-1 vaccination, both initially and a year later.

Theoretical simulations have shown that magnetic fields play an important role in massive star formation: they can suppress fragmentation in the star forming cloud, enhance accretion via disc and regulate outflows and jets. However, models require specific magnetic configurations and need more observational constraints to properly test the impact of magnetic fields. We investigate the magnetic field structure of the massive protostar IRAS18089-1732, analysing 6.7 GHz CH3OH maser MERLIN observations. IRAS18089-1732 is a well studied high mass protostar, showing a hot core chemistry, an accretion disc and a bipolar outflow. An ordered magnetic field oriented around its disc has been detected from previous observations of polarised dust. This gives us the chance to investigate how the magnetic field at the small scale probed by masers relates to the large scale field probed by the dust.

VLBI OH maser observations simultaneously in right and left circular polarization at the 1665 and 1667 MHz transitions were conducted by taking advantage of the multichannel capability of the Mk III system. The OH maser maps of the right and left circular polarization at both transitions were obtained toward the OH maser sources NGC 6334N, NGC 7538N, NGC 7538S, and G45.07+0.13.

At the suggestion of the President it was agreed to appoint a Special Committee to examine the shell forming the subject of Dr. Stopes' paper, and to report upon it. A Committee was accordingly formed consisting of the President of the Society (Dr. Allen Sturge), the Vice-President (Mr. J. Reid Moir, F.G.S.), the Secretary (Mr. W. G. Clarke), and Mr. W. H. Burrell, F.L.S.; the President to act as Chairman.

By invitation of the President, the Committee met at Icklingham Hall from May 17th to 19th. Dr. Marie Stopes was also present, to be responsible for the safety of the specimen and to give such further information as the Committee might desire.

Malignant catarrhal fever (MCF) is reviewed and recent findings described. It is defined as a fatal disease which affects many species of Bovidae and Cervidae, characterized by widespread necrosis and lymphoid cell proliferation and can be caused by at least two infectious agents. In Africa, a herpesvirus which infects its natural host, the wildebeest, without obvious symptoms causes substantial losses in cattle due to MCF. Elsewhere, the cause of MCF is unknown but circumstantial evidence implicates sheep as the source of infection. While cattle are infected only sporadically with this “sheep-associated” form ol disease, infection of farmed deer is common, representing the most serious disease threat to the industry.

It is considered that infection of sheep and wildebeest with their respective agents operates to their advantage, causing no disease in their natural host, while transmission to other ungulates has fatal consequences, eliminating these potentially competitive species.

Recent studies of the disease in deer and the transmission of MCF from deer to rabbits are described. The evidence suggests that the disease process involves a novel dysfunction of the immune system which results in a massive lymphoid proliferation and an atopic allergic response. It is considered that similar processes may also be involved as a component of other diseases of man and animals.

We have the honour of submitting on behalf of the Executive Committee a report of the operations carried out by the Silchester Excavation Fund in 1900.

The work was begun on the 4th May under the direction of Mr. Frederick Davis, whose death in July last has deprived the Committee of valuable services freely given and intelligently performed. The further conduct of the work was undertaken by Mr. Mill Stephenson and Mr. Hope, and the closing operations, which were prolonged until 4th December, were also directed by Mr. Stephenson.

I have the honour of submitting to the Society, on behalf of the Executive Committee of the Silchester Excavation Fund, a full report of the discoveries made during the year 1901. This is also the record of the continued exploration of the site for the twelfth year in succession.

Work for the season was begun on 10th May by Mr. Mill Stephenson, who directed operations throughout until their conclusion on 13th November, with the exception of five weeks in July and August, when Mr. Herbert Jones was in charge. A deep debt of gratitude is due to these gentlemen for the time and trouble they have so freely bestowed upon the work.

GaAs layers were grown in recessed silicon trenches for monolithic integration of GaAs and silicon devices. These layers were examined using cathodoluminescence (CL) and transmission electron microscopy (TEM). The CL showed no dependence on distance from the sidewall edge within its limit of resolution. Cross-sectional TEM micrographs showed the GaAs grown on the sidewall to depend on the sidewall orientation. Material grown on the near-{111} sidewalls was comparable to that grown on the well bottom, while the GaAs grown on the near-{110} sidewalls showed poorer crystal quality. A photodetector was fabricated in the recessed GaAs/Si; this device could be easily adapted to a monolithically integrated structure.

Studies were made to find evidence of louping-ill virus infection in free-living red grouse and relate this to their breeding success. In areas where ticks were abundant 61 (84%) adult grouse had antibody to the virus compared with 1 (10%) in areas where ticks were relatively scarce. Of 162 chicks tested 25 were shown to be viraemic. Infected chicks were of significantly less weight than comparably aged uninfected birds and the probability that they died was much greater than that of uninfected birds. It is concluded that the relatively poor breeding success in areas of high tick numbers was principally due to infection with louping-ill virus. The susceptibility of the red grouse to infection is discussed.

The influence of colostrum-derived antibody to louping-ill virus on the course of experimental infection was investigated in lambs. Lambs that had high titres of antibody were refractory to infection. Lambs that had low titres of antibody did not develop a viraemia but either showed an antibody reaction or were sensitized as judged by the immune response, which was typical of an anamnestic response, after rechallenge. Animals that had no antibody 34–20 days before challenge had either no or very slight viraemia, but did develop an antibody response with titres as high as those of control lambs by day 21. Lambs that had been negative for longer periods responded in a similar fashion to controls.

These findings are discussed in relation to the occurrence of disease in lambs kept in louping-ill endemic areas. It is concluded that in such areas infections of lambs are likely to be of minor importance as a cause of mortality and of little epidemiological significance.

The complex pathogen–host–vector system of the tick-borne louping-ill virus causes economic losses to sheep and red grouse in upland United Kingdom. This paper examines the spatial distribution, incidence and effect of control measures on louping-ill virus in the Bowland Fells of Lancashire. Seroprevalence in sheep at the beginning of the study varied within the area and was affected significantly by the frequency of acaricide treatment. There was a clear decrease over 5 years in the effective force of infection on farms implementing a vaccination programme, irrespective of acaricide treatment regime, however, only one third of farms apparently eliminated infection. On farms where vaccination did not occur or where vaccination was carried out intermittently, the estimated force of infection was variable or possibly increased. Thus, as befits a complex host–pathogen system, reductions in prevalence were not as dramatic as predicted; we discuss the potential explanations for these observations.

In Scotland, between 1995 and 2000 there were between 4 and 10 cases of illness per 100000 population per year identified as being caused by Escherichia coli O157, whereas in England and Wales there were between 1 and 2 cases per 100000 population per year. Within Scotland there is significant regional variation. A cluster of high rate areas was identified in the Northeast of Scotland and a cluster of low rate areas in central-west Scotland. Temporal trends follow a seasonal pattern whilst spatial effects appeared to be distant rather than local. The best-fit model identified a significant spatial trend with case rate increasing from West to East, and from South to North. No statistically significant spatial interaction term was found. In the models fitted, the cattle population density, the human population density, and the number of cattle per person were variously significant. The findings suggest that rural/urban exposures are important in sporadic infections.