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Objective: The aim of this study was to determine the extent and the future of paediatric surgery performed in Scotland outside of the designated surgical paediatric centres. Materials and Methods: An anonymous questionnaire was sent to all 111 Scottish members of the Association of Surgeons of Great Britain and Ireland. There was a response rate of 69%. Results: Overall, 45% of responders operated on children. This was independent of the surgeon's age but was related to the type of hospital that the surgeon worked in. Eighty-four per cent of responders had a lower age limit under which they would not operate and 94% stated that there were specific circumstances where they would not operate. A mean of 18.5 elective procedures (range 0–250, median two) and six emergency procedures (range 0–30, median five) were carried out by each surgeon operating on children under the age of five per annum. Only 13% of responders thought that their successor would operate on children. Conclusions: Non-specialist paediatric surgery in Scotland is currently provided by a significant number of surgeons whose successors will not continue to provide a comparative paediatric service. This has implications for local provision of care, emergency management and capacity of existing children's hospitals in the future

Background: the variability of venous reflux patterns complicate the management of venous disease. Our study investigates specific variations in venous anatomy and patterns of reflux in varying clinical situations. Methods: prospective analysis of 464 legs in 355 patients was performed by complete duplex venous mapping of both primary and recurrent varicose veins. Hand Held Doppler (HHD) and Duplex Ultrasonography (Duplex US) observations in the popliteal fossa were compared in a subgroup of 89 patients with primary varicose veins. Distribution of venous system disease was correlated with clinical severity in a subgroup of 117 affected legs which was representative of the overall study group. Results: sapheno-femoral junction (SFJ) incompetence predominated in both primary and recurrent varicose veins. Only 21% of primary legs and 25% of recurrent legs had sapheno-popliteal junction (SPJ) incompetence. SPJ incompetence was present in only 42% of cases where reflux in the popliteal region on HHD had been demonstrated. A proportion of both primary and recurrent varicose veins had evidence of deep venous incompetence (DVI). Sixty-four percent of primary leg ulcer patients had superficial incompetence alone. In patients with recurrent varicosities and ulceration, 57% had SPJ incompetence, 64% multiple sites and 50% DVI. Conclusion: the complex variations of varicose vein anatomy and functional pathology in the lower limb are currently best assessed by complete whole-leg venous duplex mapping. Eur J Vasc Endovasc Surg 25, 267–275 (2003)

These guidelines have been designed to assist in the planning, operation and interpretation of studies which would serve to assess the efficacy of drugs against internal parasites of horses. Although the term anthelmintic is used in the title and text, these guidelines include studies on drug efficacy against larvae of horse bot flies, Gasterophilus spp., which are non-helminth parasites commonly occurring in the stomach of horses. The advantages, disadvantages and application of critical and controlled tests are presented. Information is also provided on selection of animals, housing, feed, dose titration, confirmatory and clinical trials, record keeping and necropsy procedures. These guidelines should assist both investigators and registration authorities in the evaluation of compounds using comparable and standard procedures with the minimum number of animals.

In order to establish the infection pattern with gastrointestinal nematodes in ruminants in the central Kenya highlands, a study was carried out in 58 smallholder farms. The study involved monthly faecal examinations from sheep, goats and cattle and pasture sampling from eight communal grazing areas. Each month, six Dorper worm-free tracer lambs were introduced and four locally grazed cross-bred sheep were purchased for parasite recovery. The mean faecal egg counts ( FEC ) for cattle were low throughout the study period, whereas those for sheep and goats showed a seasonal pattern with high levels of infection occurring during the two main rainy seasons, especially in March, April and October. There were significant differences in egg counts over time and among farms. Haemonchus contortus was the most prevalent nematode in the tracer lambs whereas the previously exposed locally grazed sheep had significantly lower numbers of H contortus but significantly higher numbers of Trichostrongylus species The highest levels of infection in the tracer lambs occurred in November 1995 and January, May and June 1996. Based on this study, it is now possible to explore the possibility of using strategic treatments for the control of parasitic gastroenteritis in this area of Kenya.

The consequences for lambs of infection over the winter with Teladorsagia circumcincta were quantified by deliberate, trickle infection of selected animals at 7 months of age. Infected and control uninfected animals were each allocated into four groups, relatively resistant animals on a normal diet, relatively resistant animals on an isocaloric diet supplemented with urea, and relatively susceptible animals on the same two diets. Resistance and susceptibility was assessed by faecal egg counts following natural infection during the summer preceding the deliberate infection. During the deliberate infection egg counts remained low and most parasites recovered at necropsy were inhibited larvae. Nonetheless, infection reduced weight gain, decreased albumin and fructosamine concentrations and provoked a noticeable pepsinogen and eosinophil response. As most larvae were inhibited these responses may have been largely a consequence of immuno-inflammatory responses in the host rather than the direct action of parasites themselves. Relatively resistant animals on the supplemented diet allowed fewer larvae to establish and had higher fructosamine concentrations, higher albumin concentrations and decreased pepsinogen responses. Therefore, a combination of relatively resistant sheep and nutritional supplementation appears most efficient at controlling infection.

Previous research has shown that supplementing the diet of growing lambs with urea enhances their ability to withstand gastrointestinal infection with the nematode Haemonchus contortus. This study compared lambs given two different amounts (χ 1 and χ 1·5) of the same urea-supplemented diet. One dietary allowance was sufficient to allow uninfected lambs to gain approximately 400 g/week without adverse clinical signs. In contrast half of the H. contortus infected lambs on this dietary allowance had to be humanely killed before the end of the experiment due to severe anaemia and anorexia. All infected lambs on this dietary allowance showed decreased mean red cell volumes and decreased plasma albumin concentrations indicating inadequate replacement of red blood cells and plasma proteins lost during the infection. The remaining lambs were offered proportionately 0·5 more of the same dietary allowance. Among lambs on this dietary allowance, there were very few differences between uninfected and infected sheep in clinical signs and growth rate. Therefore, dietary allowances that are adequate for uninfected lambs are not necessarily sufficient for infected lambs. As nearly all grazing lambs are infected with nematodes, dietary recommendations should take parasitic infection and its nutritional demands into account.

Maiden Red Maasai and Dorper ewes were kept indoors and artificially infected with a single oral dose of 5000 infective larvae of Haemonchus contortus. Their faecal egg counts (FEC) and packed red cell volumes (PCV) were monitored for 9 weeks. They were then treated with an anthelmintic and turned out to graze together on a pasture contaminated with H. contortus. They grazed this pasture for 14 months and were allowed to mate and lamb. While at pasture the ewes were monitored for FEC, PCV and peripheral eosinophilia. Red Maasai ewes had significantly lower FEC, and for certain periods, significantly higher PCV and peripheral eosinophilia. During the periparturient period, FEC were about twice as high in the Dorper breed as the Red Maasai. These results confirm and extend previous reports on the superiority of the Red Maasai breed in East Africa.

Six-month-old red Maasai lambs were more resistant than Dorper lambs to repeated infections at one to two week intervals with 1000 Haemonchus contortus infective larvae. Resistance after infection was assessed by means of faecal egg counts, packed cell volumes, eosinophil counts, total serum protein concentrations and mortality rates. The weight gains of the infected animals were only marginally lower than those of their uninfected controls, most probably because of their significantly higher feed consumption, and evidently the infected lambs were not utilising all of the extra feed for growth. This absence of anorexia in spite of the infection was probably due to the palatability of the high protein diet fed to the lambs.

Protein supplementation improves the resistance of sheep to haemonchosis. This experiment investigated the Scottish blackface breed to establish whether dietary protein supplementation is still beneficial in a genetically resistant breed. Lambs were given either a basal diet or a diet supplemented with soyabean meal to give an additional 80 g crude protein kg dry matter−1. The lambs were given an initial loading dose of Haemonchus contortus, followed by a trickle infection for 10 weeks. The weight gains of the lambs given the supplemented diet were greater and their carcases were leaner, irrespective of infection status. Infected animals on the basal diet were more anaemic and hypoalbuminaemic than animals receiving the supplemented diet, although there were no statistically significant differences in mean worm burdens or faecal egg counts.

The adult ES products of Dictyocaulus viviparus are a source of protective antigens against challenge in the guinea pig laboratory model. High levels of acetylcholinesterase (AChE) activity are present in these products and these enzymes are immunogenic in infected cattle. Here, the potential role of these enzymes in protective immunity was investigated using a fraction enriched for AChE to immunise guinea pigs. The antibody response stimulated by immunisation with AChE-enriched ES products and the worm burdens obtained following challenge with infective larvae were compared with those in animals immunised with whole ES products and challenge controls. The AChE-enriched preparation stimulated high levels of enzyme-specific antibody in immunised animals, which was not the case for those which received unfractionated ES products. Worm burdens of guinea pigs which received the AChE-enriched fraction were significantly lower than those obtained in adjuvant controls. The animals which received the unfractionated ES products were not significantly protected against challenge. These results suggest that AChEs may be potential candidates for incorporation in a sub-unit vaccine against D. viviparus .

Faecal egg counts, peripheral blood eosinophil counts and plasma pepsinogen concentrations were monitored during 2 successive, deliberate infections in 24 Scottish Blackface sheep. For all 3 techniques, the repeatability of replicate counts or of measurements made at short intervals were high which suggests that all 3 assays were reliable. Within an infection the repeatability of different samples from the same animal decreased as the interval between samples increased. The repeatability between infections was only moderate for faecal egg counts but high for peripheral eosinophil counts and plasma pepsinogen concentrations. Of the 3 variables, faecal egg count was the most strongly associated with the worm burden. Together, the three variables accounted for, in a statistical sense, one half of the variation in worm burden. The three variables, if measured concurrently, should provide a more effective identification of resistant and susceptible lambs.

This chapter shows how sheet may be bulged to an approximately spherical shape by fluid pressure. This process is used to obtain mechanical properties in sheet in the so-called hydrostatic bulging test. The chapter also shows equipment designed to obtain an effective stress strain curve by bulging a circular diaphragm with hydrostatic pressure. For punches that are not hemispherical, the strain distribution depends on the punch shape. Friction also affects the strain distribution and the greatest punch displacement. Normally, friction is confined to the punch comer radius. This prevents the tension across the face of the punch from increasing sufficiently to stretch the material over the face of the punch. The maximum depth that can be formed is therefore less with friction than without it. Stretching over a punch is often a pre-form operation, where material is redistributed to obtain favorable conditions for the final stage. In the second stage, the shape of the punch is defined by the part design; but for the preform punch, there is some flexibility in the shape and the tool designer needs to consider both curvature and friction in arriving at a suitable tool.

We report an unusual and not previously described congenital hindgut malrotation presenting as large bowel obstruction in an adult.

The efficacy of five daily treatments with 7.5 mg fenbendazole/kg bodyweight against mucosal cyathostome larvae was evaluated in 20 12- and 24-month-old ponies with naturally acquired cyathostome infections. After three weeks communal grazing on infected pasture and six weeks indoors, one group of 10 ponies were treated. Six weeks later, both groups of ponies were humanely destroyed and their burdens of large intestinal cyathostome worms, including luminal parasites and mucosal larvae, were assessed. In the control animals approximately 7 per cent of the total worm burden was present in the gut lumen and 93 per cent was present as larvae in the large intestinal mucosa. The efficacy of fenbendazole against the luminal cyathostomes was 90.7 per cent (P < 0.01). The total numbers of mucosal larvae, recovered after digestion, were reduced by 95.3 per cent (P < 0.0005); mucosal late third and fourth stage larvae were reduced by 99.4 per cent (P < 0.0001), and early inhibited third stage larvae by 91.5 per cent (P < 0.005).

In many farming enterprises, animal management systems which could provide a practical and effective alternative to chemotherapy for the control of bovine helminthosis would be readily accepted. One system which has been proposed and shown to be effective in the short or medium term involves grazing different host species on a rotational basis. The study described here examined the effect of alternating cattle and sheep annually over an extended period of 4 years. Up to the second grazing season the system appeared to be successful, with a marked reduction in the cattle worm burdens. However, by the end of the study period the parasite burdens in calves grazed on the alternated pasture were equal to, or greater than, those of set-stocked control animals. It was thus clear that the alternate grazing strategy had failed. Data obtained from other parameters measured, i.e. faecal egg counts, pasture larval numbers and plasma pepsinogen levels, confirmed this observation.

Twenty helminth-naive Scottish Blackface lambs were given three infections with 10 000 infective larvae of Haemonchus contortus at 8 week intervals. An additional six lambs served as uninfected controls and eight lambs were infectivity controls. The lambs were 7 months old at the start of the infection. Four of the 20 lambs developed severe haemonchosis and were put down during the experiment. The remaining 16 lambs plus uninfected controls were necropsied 8 weeks after the third infection. The mean faecal egg count peaked 6–8 weeks after the first infection, gave a second smaller peak 6–8 weeks after the second infection but produced no peak after the third infection. Mean red blood cell counts fell rapidly during the first infection, then rose gradually during the second and third infections. The mean values suggested that the two infections were sufficient to produce effective immunity in the sheep population but they masked considerable individual variation. Eleven animals appeared relatively resistant following the first infection, while two animals were relatively susceptible to even the third infection. The repeatability of mean faecal egg counts or mean red blood cell counts for each animal during the replicate infections were very high, because the rankings of the individual sheep remained remarkably stable. Faecal egg counts were very strongly correlated with red blood cell counts. Multiple regression analysis showed that four factors—faecal egg counts, red blood cell counts, weight and sex—accounted for essentially all of the observed variation in worm burdens among the lambs. Therefore, under these controlled experimental conditions, additional markers appear unnecessary for the detection of resistance status.

Faecal nematode egg counts were monitored in 184 Scottish Blackface lambs during natural exposure to a mixed, predominantly Ostertagia circumcincta infection and 12 lambs were selected which showed consistently zero (low count group; nine lambs) or consistently positive faecal egg counts (high count group; three lambs). These lambs were then treated with anthelmintic and challenged with 50 000 infective larvae of O. circumcincta and monitored thrice-weekly for 38 weeks; they were then re-challenged with another 50 000 infective larvae of O. circumcincta and monitored for a further 8 weeks. All sheep gave positive egg counts following deliberate infection. However, there was considerable variation among sheep in the size and timing of the peak in egg production. In particular, the pattern of mean values for faecal egg counts was different in the two groups. Egg counts were lower in the later periods of the extended infection in both groups of sheep. During the first half of the extended infection, egg counts were lower in sheep from the low count group, but during the second half of the infection the pattern was reversed and egg counts were lower in sheep from the high count group. There was a weak positive correlation between egg counts following anthelmintic treatment and 28 days exposure to natural infection and egg counts 28 days after a deliberate infection. Egg counts in the later stages of the deliberate infection were strongly but negatively correlated with egg counts following natural infection. The results of these studies show that differences in egg count following natural infection can be reproduced in experimental infections and that there is substantial variation in the pattern of egg production over time in different sheep. They also suggest that naturally resistant lambs are better able to delay worm development than naturally susceptible lambs.

A strain of Haemonchus contortus, susceptible to ivermectin (IVM), was submitted to a selection procedure using IVM at 0.02 mg kg−1 during nine successive passages in lambs. Treatment reduced worm egg counts (epg) by more than 99% up to the seventh passage, but thereafter there was no significant reduction in epg. The efficacy of ivermectin against the ninth selected generation compared with the original susceptible strain was assessed. The results showed that animals infected with the selected strain and treated with IVM did not show any significant reduction (P > 0.05) in epg compared with a 99.9% reduction in the susceptible group. At necropsy, post-treatment worm burdens confirmed that the selection pressure applied to the original strain had been successful in stimulating resistance to IVM.

The free-living development of three strains of Haemonchus contortus was studied in two experiments. Day 21 faecal samples were collected from lambs infected with either a susceptible strain, a laboratory-selected ivermectin (IVM) resistant strain or a South African field strain showing multiple anthelmintic resistance, which included IVM. No eggs hatched in samples cultured at 4 or 10 degrees C. At 22 degrees C the laboratory-selected strain showed the highest rate of development while at 27 degrees C the susceptible strain produced the highest yield of third stage larvae (L3): at both temperatures the field strain showed the lowest percentage development to L3. The second experiment was a field study carried out in southern Brazil. Faeces containing either an IVM-susceptible or an IVM-resistant strain of H contortus were placed in two series of grass plots during each of three summer months. Soil subsequently yielded more larvae than did grass suggesting migration or mechanical transport into the soil. For plots contaminated during the first two months there was no significant difference in recovery rate between the two strains (P > 0.05). When contamination occurred during the third month, the IVM-resistant strain produced significantly higher recovery rates (P < 0.05) from both pasture and soil.

The relationship between anti-parasite IgA antibody levels in plasma and the periparturient egg rise in sheep was investigated. Ostertagia circumcincta larvae (5000 third stage larvae three times weekly) were administered to three groups of seven adult immune ewes from 12 weeks before until three weeks after lambing (group 1) or from six (group 2) or 14 (group 3) weeks before until three weeks before lambing. Seven additional ewes were not challenged (group 4 controls). Ewes in groups 1, 2 and 4 received anthelmintics 14 weeks before lambing. Challenge of the pregnant ewes with O circumcincta larvae resulted in substantial increases in faecal egg counts only during the periparturient period regardless of the larval dosing regimen. Furthermore, the periparturient rise in faecal egg counts was closely associated with a significant increase in anti-parasite IgA antibody levels in plasma. This rise in IgA antibody levels occurred at a time when IgA is transported from the gut to milk during early lactation. It is postulated that this may lead to a temporary reduction in abomasal antibody levels of ewes and hence permit the establishment of larvae and, or, the emergence and development of inhibited larvae and thereby lead to the periparturient rise in faecal egg count.

Following evidence of reduced efficacy of ivermectin in a field population of Haemonchus contortus in Brazil, this strain of the parasite was submitted to a controlled anthelmintic test. Eighty worm-free lambs were randomly split into two groups of 40. Each lamb in the first group was infected with 5000 third stage larvae (L3) of the ivermectin-resistant strain; the remaining 40 lambs were each infected with 5000 L3 of a H. contortus strain of known susceptibility to the major groups of anthelmintic compounds used in sheep. On Day 28 post-infection, each group was subdivided according to egg counts and at random into four sub-groups of ten lambs, each of which was treated with albendazole (ABZ) at 3.8 mg kg−1, levamisole (LEV) at 7.5 mg kg−1 or ivermectin (IVM) at 0.2 mg kg−1, or was left as untreated control. At slaughter, 7 days later, all the anthelmintics reduced worm burdens in animals infected with the susceptible strain (ABZ 98.9%, LEV and IVM 100%). By contrast, in the lambs infected with the ivermectin-resistant strain, LEV was 99.8% effective, but ABZ reduced worm counts by only 14.7% and IVM by only 10.4%. Interestingly at necropsy on Day 7 post-treatment, the egg counts in the resistant strain treated with ABZ had been reduced by 92.5%, although worm counts were reduced by only 14.7%. Benzimidazole resistance had been confirmed previously on this farm and although benzimidazoles had not been used during the last 5 years, this ivermectin-resistant strain was still highly resistant to ABZ; LEV remained as the only drug evaluated which was still effective against this population of H. contortus.

The clinical signs, pathology and clinical pathology associated with single experimental infections of Strongyhts vulgaris in worm-free pony foals are described. The major clinical signs which became apparent in the infected foals during the first three weeks were pyrexia, anorexia, dullness and abdominal pain. Within the first two weeks of infection lesions were confined to the intestine and terminal branches of the intestinal arteries and consisted of mucosal, submucosal and serosal haemorrhage together with arteritis of submucosal and serosal arteries and also a marked inflammatory reaction. The main lesion seen three weeks after infection was gross thrombosis of the anterior mesenteric artery or one of its major branches. On section these affected arteries showed marked intimai thickening with infiltration of plasma cells, lymphocytes, macrophages and neutrophils. Between one and four months after infection the gross lesions were predominantly in the arteries and consisted of fibrous thickening of the arterial wall and thrombosis associated with the presence of developing fourth stage larvae. Four months after infection the arterial lesions were still prominent and microscopically there was fibrosis of the wall of the affected artery with widespread disruption of the intima. In the adventitia organised thrombi were apparent in the vasa vasorum and resulted in the obliteration of their lumina. The typical lesion associated with the return of fifth stage-larvae to the intestine was nodule formation in close proximity to thrombosed terminal intestinal arteries and sections of parasites were seen in the intestinal wall surrounded by neutrophils and necrotic debris. By nine months after infection the arterial lesion had healed, but histologically there was fibrosis of the intima and macrophages containing haemosiderin were seen in the arterial wall. The most significant haematological findings during the experimental period were a marked polymorphonuclear leucocytosis and an increase in the number of circulating eosinophils in the infected animals. Also marked was an increase in the serum globulin levels of the infected foals.

Six worm-free pony foals, two to four months old, were infected with parascaris equorum eggs using three different dosage regimes and killed at either 40 or 95-100 days after infection. Coughing and a circulating eosinophilia were features of large infections from which only a small number of worms developed to maturity. In small infections a high percentage of the parasites matured in the small intestine and this was associated with unthriftiness. Pre-patent periods of 80 and 83 days were recorded.

Eight worm-free pony foals, aged 2–4 weeks received a single infection of 8000 Parascaris equorum eggs . The foals were killed at intervals to investigate the migration and subsequent development of P. equorum . Signs of larval invasion were found in the liver within 48 h after infection. Larvae migrated from the liver to the lungs from 7 to 14 days after infection and the majority had returned to the small intestine via the tracheooesophageal route by day 23. After completion of their tissue migration, the parasites grew rapidly in size in the lumen of the small intestine, but after day 37 the total number of worms present in this site decreased. Patent infections developed on days 101–104.

The general harmonic force field of methylene chloride has been calculated without the necessity of imposing constraints, through the use of a set of 74 observables over eight isotopic species. These include vibration frequencies, 37 Cl and 13 C isotopic frequency shifts, and quartic centrifugal distortion constants. All force constants are well defined by the data with one exception, and this takes a value close to that predicted by transfer from methyl chloride, although with an uncertainty larger than itself. The force field is used to predict precise isotopic distortion constants, in terms of differences from the accurate experimental values for CH 2 35 Cl 2 and CD 2 35 Cl 2 , and to calculate Coriolis interaction constants which will be of assistance in high-resolution rovibration studies. Alternative definitions which may be used for the deformation coordinates of an XY 2 Z 2 molecule are considered. That which associates each deformation uniquely with either the XY 2 or XZ 2 group is clearly preferred.

Ground state rotational constants over 8 isotopic species have been used to determine precise structural parameters for methylene chloride, with the assistance of the recently determined empirical general harmonic force field. The isotopic zero-point inertial constants are used to estimate equilibrium structural parameters, through a recently developed mass-dependence method, which yields values of r e (H··H) = 1.7876 A and r e (Cl··Cl) = 2.9292 A.

An ab initio gradient calculation of the general harmonic force field (GHFF) of methylene chloride at the HF-SCF/6-31 G** level has been undertaken. The results compare favourably with those determined empirically, thus demonstrating a good predictive capability at this level of sophistication for a molecule possessing two third row halogen atoms. The ab initio results reveal small inadequacies in the empirical force constants relating to the CH2 moiety, which may be corrected by a careful re-appraisal of the accumulated spectroscopic data. The resulting empirical and scaled quantum mechanical (SQM) sets of force constants are then in very good accord. Predicted ab initio cubic force constants for methylene chloride are also calculated.

The respective roles of age of lamb, size of immunizing dose, previous exposure to infection and anthelmintic therapy on the immune response of Scottish Blackface sheep to gamma-irradiated H. contortus larvae were studied. As previously shown, young lambs immunised at 10 and 14 weeks of age failed to develop a significant resistance to subsequent challenge. In contrast, parasite-naive lambs immunised at 9 and 10 months of age with 10 000 H. contortus larvae irradiated at 60 kilorontgens developed a highly significant immunity to subsequent challenge. This degree of immunity was not significantly altered by the administration of spaced doses of normal larvae from 10 weeks of age until the point of vaccination. Worm-free lambs vaccinated at 9 and 10 months of age failed to develop any immunity to subsequent challenge when the anthelmintic thiabendazole was administered 3 weeks after each immunizing infection.

In the West of Scotland the epidemiology of parasitic bronchitis in grazing calves was studied over a two year period with the aid of tracer calves and herbage examinations for Dictyocaulus viviparus larvae. The observations of both years emphasised the importance of overwintered lungworm larvae as a source of disease. In the first year it was shown that the ingestion and development of these overwintered larvae were, by themselves, directly responsible for severe morbidity, high faecal larval counts and deaths. In the second year it was shown that pasture ungrazed during the winter and spring and from which a hay crop was removed in mid-summer was still capable of producing clinical parasitic bronchitis in susceptible calves within three to four weeks of their introduction in later summer. In both years there was some evidence that the outbreaks appeared to be associated with the sudden availability of infective larvae on the herbage. The possibility that such larvae may have survived for many months in the soil is discussed. Despite the heavy challenge with lungworm larvae experienced by the grazing calves in the first year those vaccinated with lungworm vaccine survived, their clinical signs were mild and of short duration and their faecal larval output was greatly reduced.

Plasma pepsinogen levels became elevated in groups of recipient calves immediately after transplant with adult Ostertagia ostertagi. These rises occurred in both previously parasite-naive calves and in calves which had experienced prior infection terminated with an anthelmintic either seven or 21 days before transplant. From the results it appears that adult O ostertagi play a significant role in the elevated plasma pepsinogen levels associated with bovine ostertagiasis.

The histological changes in the abomasal mucosa of pairs of worm-free ewes and lambs were compared at various stages after infection and reinfection with 350 Haemonchus contortus L3 per kg bodyweight. In terms of worm burdens the ewes were relatively resistant to reinfection compared with the lambs and the histological changes in the abomasum at most stages after infection were more marked in the adult animals. These included increases in the numbers of mast cells, globule leucocytes, eosinophils and IgA plasma cells in the mucosa.

Eight pony foals 2 to 4 weeks old were infected with a single dose of 8000 P. equorum eggs. The animals were killed at intervals to investigate the pulmonary lesions produced. Two distinct lesions were found in the lungs. The migrating P. equorum larvae provoked a transitory eosinophilic bronchitis and bronchiolitis which was later replaced by a lymphocytic response. Large numbers of subpleural lymphocytic nodules were also present for a short period. In addition, there was a cranial lobe pneumonia with a mainly polymorphonuclear leucocytic response. It is suggested that this second lesion may be a form of enzootic pneumonia and that its pathogenesis is enhanced by the migrating P. equorum larvae.

The ν 7 C -type CH 2 rocking and ν 8 A -type CH 2 wagging fundamentals of CH 2 Cl 2 have been recorded at a resolution of ∼ 0.04 cm −1 , and the ν 2 + ν 8 A -type combination at a resolution of ∼ 0.005 cm −1 . All three bands are analysed in terms of the quartic asymmetric rotor model, yielding precise vibrational and rotational parameters. Although each band appears to suffer minimal perturbation effects, assignment proved difficult due mainly to the effects of the overlapping spectrum of CH 35 2 Cl 37 Cl, but also to the small magnitude of the B and C rotational constants (∼ 0.1 cm −1 ). In the case of ν 7 , band contour simulations were required in order to confirm or refute possible assignments. The data obtained for ν 8 and ν 2 + ν 8 enable parameters to be predicted for the extremely weak ν 2 CH 2 deformation fundamental, only recently observed in the gas phase spectrum.

Values of A e and B e for the H 3 and D 3 methyl chlorides, bromides, and iodides are calculated from the best present estimates of values of A 0 , the microwave values of B 0 , and the α r a and α r b data. The theoretical A e (CH 3 X/ A e (CD 3 X) ratio is well obeyed in methyl iodide and bromide, but a discrepancy of 1 % is observed in methyl chloride. It is concluded that A e (CD 3 Cl) is slightly high, possibly as a result of the lack of precise data available from the strongly overlapped and Coriolis interacting fundamentals v 2 and v 5 . The equilibrium rotational constants predict the molecular parameters: methyl chloride r e (CH) = 1.086 ± 0.004 A, R e (CCl) = 1.778 ± 0.002 A, α e (HCH) = 110° 40'± 40'; methyl bromide r e (CH) = 1.086 ± 0.003A, R e (CBr) = 1.933 ± 0.002 A, α e (HCH) = 111° 10'± 25'; methyl iodide r e (CH) = 1.085 ± 0.003 A, R e (Cl) = 2.113 ± 0.002 A, α e (HCH) = 111° 17'± 25'; For methyl fluoride, for which the α r a and α r b data are not so complete, the A 0 and b 0 values are corrected to A e and B e by considering the trends in ( A e – A 0 ) and ( B e – B 0 ) in the other halides. Almost precise agreement with the theoretical ratio is obtained with the A e values. The equilibrium rotational constants predict the molecular parameters: methyl fluoride r e (CH) = 1.095 A, R e (CF) = 1.382 A, α e (HCH) = 110° 27'. No estimates of uncertainty are made, as the results depend entirely on the validity of the extrapolation process used to obtain A e and B e values. The considerably larger CH bond length in comparison with the other halides is supported by the observations that the unperturbed CH 3 and CD 3 stretching vibration frequencies are much lower, and that the CH stretch force constant is significantly smaller, than in the other halides.

General harmonic and hybrid orbital force fields have been calculated for methyl chloride, bromide and iodide using the best available frequency, Coriolis coefficient, and centrifugal distortion data, including the recent 13C frequencies for the chloride and iodide. Anharmonicity corrections were made to the fundamental frequencies using Dennison's rule and x values of 0·04 for CH stretching, 0·02 for CH bending, and 0·01 for CX stretching modes. These were the most reasonable values which did not seriously over-compensate for the product rule deficiencies in the 12C and 13C frequencies. The 13C and CD3X frequency information was input in the form of frequency shifts from the 12CH3X frequencies. All 12 parameters in the most general harmonic force fields are determined with significance for the first time, although the previously uncertain parameters F12 and F13 are only determined with good precision when the 13C frequency data are utilized in addition to the other information. The signs of F12, F45 and ...

Summary In an attempt to elucidate the migratory route of Strongylus vulgaris larvae 9 worm-free pony foals were each infected with a pure culture of 750 infective larvae and killed at intervals over a period of 9 months. The results obtained show that infective larvae exsheath and penetrate the intestine within a few days of infection. These larvae then moult in the sub-mucosa, penetrate small arteries and have migrated within the lumina of intestinal arteries to the anterior mesenteric site by 14 days. In the predilection site larvae develop from early to late fourth stage and after a period of 3 to 4 months the fourth moult is completed and young adults return to the intestine again via the lumina of the arteries. Nodules are formed with the subsequent release of young adults into the intestinal lumen. The migration is complete by 6 to 7 months after infection.

The infrared spectrum of CHD2I has been recorded at a resolution of ∼0.2 cm−1. Analyses in terms of the Q branches of five type B and type C fundamentals have been performed, and the band centers of all other fundamentals accurately located. The averaged value of A0 determined in this work is found to be almost perfectly compatible with the recent experimentally observed value of A0 for CH3I. The ground state geometry, determined from the rotational constants of CH3I, CD3I, 13CH3I, and CHD2I is found to be r CH 0 = 1.088 ± 0.002 A , r CD 0 = 1.086 ± 0.002 A , r CI 0 = 2.1423 ± 0.0015 A , αHCH0 = 111°31′ ± 15′. Ground state geometries for methyl bromide and methyl chloride are predicted.

A sensitive infrared method for quantitative determination of vapours has been used to study some of the reaction variables in the Zeisel alkoxyl determination. Several conflicting reports in the literature have been clarified. Reaction conditions giving rapid and accurate determinations on solids and volatile liquids, even in presence of large sulphur concentrations, are described: for determinations on vanillin the standard deviation is 0.16%. Interaction between alkyl iodides and sulphuretted hydrogen has been found to occur only in aqueous solutions; the use of soda-asbestos as a solid scrubber therefore has fundamental advantages over aqueous solutions, and gives excellent results.

BackgroundAbdominal aortic aneurysms (AAA) are responsible for 1.4% of UK deaths. Deprivation is a risk factor for AAA. Screening reduces AAA related mortality and is cost effective if uptake remains high. The Highland aneurysm screening programme (HASP) began in 2001 offering screening to men in a sparsely populated area. The aim was to identify whether uptake varies with deprivation or rurality, in the context of an established programme.MethodsRetrospective interrogation of HASP records was performed on all men offered screening from 2001 until 2010. Deprivation and rurality status were derived from postcode of residence (SIMD'09 and URC'08) and the relationships with screening uptake were examined.ResultsMean uptake over the decade was 90.1%. There was a strong association between deprivation and uptake, which ranged from 79.5% in the most deprived population to 97.5% in the least deprived (p

A reexamination of the ν 4 3ν 6 1 Fermi diads in 12CH3Cl and 13CH3Cl has been performed in the light of the recent results of Maki and Thibault for the 12CH3Cl diad, obtained under conditions of very high resolution. This has enabled the unperturbed band centers of the two components of the 13CH3Cl diad to be located much more accurately than reported in a recent paper by the authors.

The mechanisms involved in the pathophysiological disturbances associated with the presence of mature Parascaris equorum in the small intestine were investigated with radioisotopic techniques. The results suggested that, compared with worm-free controls, infected foals had a reduction in gut motility, an increase in the body solids ratio, a lowering of the body pool of albumin and a decreased ability to incorporate dietary methionine into plasma protein.

The efficacy of a morantel sustained release bolus to control ostertagiasis in grazing calves was assessed. Administration of the bolus into the rumen of calves immediately before turnout on to spring pasture in May substantially reduced the level of pasture contamination with infective larvae later in the season. Compared with controls there was a 71 per cent reduction in worm burdens acquired over the entire grazing season with a mean improvement in weight gain of 24 kg. When administration was delayed until midsummer (July) a good anthelmintic effect was obtained but there was little reduction in pasture contamination levels. Worm burdens acquired over the grazing season were reduced by only 48 per cent with a mean weight gain advantage of only 9 kg compared with controls. The control obtained against Dictyocaulus viviparus by both treatments was not absolute, failing to prevent the development of mild parasitic bronchitis.

The clinical, parasitological and pathological findings in a group of six donkeys naturally infected with D arnfieldi larvae are described. One animal had to be sacrificed at an early date because it developed pneumonia. The remaining five were unthrifty, showed mild clinical respiratory signs and had heavy strongyle infections. They had varying numbers of adult worms in the airways of the lungs and eggs were found coiled up in the smaller bronchi where they had apparently lead to an obstruction to airflow in that segment. The most striking gross pathological changes were circular discrete areas of over-inflation surrounding such bronchi. Histologically the infected bronchi exhibited a marked bronchiolitis with goblet cell hyperplasia and a mainly lymphoid inflammatory infiltrate. These areas also showed a localised bronchiolitus and overinflated alveolar tissue although true emphysema was not present. It is postulated that the parasite is well-adapted to its host and is able to survive for long periods within the lung without causing a debilitating amount of damage to the host. The immunological aspects of the infection are discussed briefly.

Considerable advances have been made over the last decade in the efficacy of the anthelmintics available for treatment of helminthiases in dogs, cats and horses. With the advent of new drugs, it has also come to be appreciated that the effectiveness of previously-used compounds was not as great as had been thought. Because of the large number of compounds now available the choice of drug has become confused and this paper is intended to classify the efficacy of the currently-available anthelmintic drugs and to indicate the possible hazards in their use.

These guidelines have been designed to assist in the planning, operation and interpretation of studies which would serve to assess the efficacy of drugs against internal parasites of horses. Although the term anthelmintic is used in the title and text, these guidelines include studies on drug efficacy against larvae of horse bot flies, Gasterophilus spp, which are non-helminth parasites commonly occurring in the stomach of horses. The advantages, disadvantages and application of critical and controlled tests are presented. Information is also provided on selection of animals, housing, feed, those titration, confirmatory and clinical trials, record keeping and necropsy procedures. These guidelines should assist both investigators and registration authorities in the evaluation of compounds using comparable and standard procedures with the minimum number of animals.

Following infection with 8000 Parascaris equorum eggs in two- to four-week-old foals reared under worm-free conditions a high percentage of the infective dose completed its tissue migration and returned to the small intestine. Patent infections were establisehd between 81 and 104 days after infection and high faecal egg counts were recorded. A group of six- to 12-month-old foals, which had been either reared under worm-free conditions or exposed to natural ascarid and strongyle infections on pasture, received a similar infection of 8000 P equorum eggs. Compared with the younger foals there was a marked reduction in the number of larvae reaching the small intestine. Also, patent infections were established less frequently (50 per cent of cases) and, when present, the faecal egg counts remained low.