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The molecular epidemiology of 70 Escherichia coli isolates from an infection outbreak in a layer breeder flock was examined by pulsed-field gel electrophoresis and for a range of virulence factors by polymerase chain reaction. Pulsed-field gel electrophoresis showed 35 of 45 isolates from eight disease cases were associated with a single clonal group that was the exclusive strain associated with reproductive tract. A second unrelated group was found in environmental isolates and healthy birds. The remaining isolates were unrelated to each other or either clonal group. Polymerase chain reaction virulotyping indicated the "epidemic" clonal group contains virulence factors including iss, sfa, tsh, iucC, ibeA, and sitA associated with avian pathogenic E. coli plus several virulence factors more normally associated with human urinary tract infection. Significantly, the "epidemic" clone was also found in an environmental sample, suggesting it may have been transmitted to the flock via the environment.

A flock of 13,951 hens and 1379 cockerels was monitored from 26 to 58 weeks of age for the complex of salpingitis, peritonitis and salpingoperitonitis (sps). Two hundred and forty-three hens (78 per cent of the hens that died) were examined postmortem, and sps was recognised by gross examination for inflammatory exudate, in the body cavity or oviduct in 111 (46 per cent) of them. Salpingoperitonitis was the most common form, followed by salpingitis and then peritonitis. There were acute and chronic cases in all three conditions, but only in peritonitis were acute cases more common than chronic cases. Seventeen birds that had died of sps were cultured for aerobic bacteria within 12 hours of death. Escherichia coli was recovered from a variety of tissues from all of them, and other bacteria, including staphylococci, Mannheimia haemolytica and Streptococcus bovis, were isolated from a few carcases, either alone or together with E coli. Relatively few isolations of E coli were made from normal hens cultured 48, 72 and 96 hours after death.

In vitro toxicology methods are being adopted by regulatory agencies worldwide. Many of these methods have been validated by using proprietary materials, often in the form of test kits. Guidelines for the use of Good Laboratory Practice methods for in vitro methods have been proposed. However, users of the data from these methods also need to be reassured that the proprietary materials and the test kits will provide consistent, good quality data over time, not just during the validation process. This paper presents an overview of the methods currently used by representatives of kit manufacturers and contract testing laboratories to ensure that the results from methods that utilise test kits are reproducible over time and across different types of test materials. This information will be valuable as a basis for future discussion on the need for formalised oversight of the quality of these materials.

Background: Several authors have reported success using a gas-mediated transperitoneal approach for lumbar interbody fusion. However, this approach has not been shown to reliably and predictably address segments above L4-5., Methods: The B.E.R.G. approach was attempted in 202 patients who required anterior lumbar interbody fusion (ALIF). Of those, 168 were completed successfully without conversion to an open procedure. The anterior retroperitoneal approach required no gas insufflation. The gasless environment allowed for the use of standard anterior instrumentation and a variety of fusion grafts and devices., Results: Mean hospital stay was 1.95 days, with 73% of patients discharged in <47 h following surgery. Clinical results from the first 50 patients, with a minimum 2-year follow-up, include a 92% fusion rate and 78% of patients reporting significant pain relief of greater than 50%., Conclusions: The B.E.R.G. approach offers significant technical advantages over the standard gas-mediated transperitoneal approach for ALIF. The clinical results are similar to those reported for open approaches and the gas-mediated transperitoneal approach.

A retrospective preliminary study was undertaken of combined minimally invasive instrumented lumbar fusion utilizing the BERG (balloon-assisted endoscopic retroperitoneal gasless) approach anteriorly, and a posterior small-incision approach with translaminar screw fixation and posterolateral fusion. The study aimed to quantify the clinical and radiological results using this combined technique. The traditional minimally invasive approach to the anterior lumbar spine involves gas insufflation and provides reliable access only to L5-S1 and in some cases L4-5. A gas-mediated approach yields many technical drawbacks to performing spinal surgery. A minimally invasive posterior approach involving suprafascial pedicle screw instrumentation has been developed, but without wide-spread use. Translaminar facet fixation may be a viable alternative to transpedicular fixation in a 360 degrees instrumented fusion model. Past studies have shown open 360 degrees instrumented lumbar fusion yields high arthrodesis rates. The study examined the cases of 46 patients who underwent successful 360 degrees instrumented lumbar fusion using a combined minimally invasive approach. Anterior lumbar interbody fusion (ALIF) at one or two levels was performed through the BERG approach; a gasless retroperitoneal approach to the lumbar spine allowing the use of standard anterior instrumentation. Posteriorly, all patients underwent successful decompression, translaminar fixation, and posterolateral fusion at one or two levels through one small (2.5-5.0 cm) incision. Results showed mean hospital stay of 2.02 days; mean combined blood loss was 255 cc; and mean pain relief was 56%, with 75.5% of patients reporting good, excellent, or total pain relief. Forty-two of 46 patients (93.2%) achieved a solid fusion 24 months after surgery. A total of 47% of all patients working prior to surgery returned to work following surgery. The study showed that minimally invasive 360 degrees instrumented lumbar fusion, when performed utilizing these approaches, yields a high rate of solid arthrodesis (93.3%), good pain relief, short hospital stays, low blood losses, accelerated rehabilitation, and a quick return to the workforce. The BERG approach offers technical advantages over the traditional gas-mediated laparoscopic approach to the anterior lumbar spine.

A virulent strain of Mycoplasma gallisepticum (MG) was used to infect groups of 40 2-day-old poults kept in separate pens of 10 each. Of the six groups, three were treated with separate concentrations of tilmicosin, one was treated with tylosin, one remained untreated, and a final group was not infected and not treated. Mortality, clinical signs, and gross lesions were significantly less (P < 0.001) in the uninfected and infected medicated groups than in the infected unmedicated group. Also, the mean body weight gain of poults surviving to the end of the experiment was greater (P < 0.005) in the uninfected and infected medicated groups. MG was not recovered from the uninfected birds, and, among the infected poults, it was recovered from significantly fewer (P < 0.05) poults in the medicated groups. Serologic results were negative for the uninfected group, and there were fewer positive reactors for the infected medicated than the infected unmedicated group. In consideration of these results, tilmicosin should prove to be a useful addition to the antimicrobials in the treatment of MG infection in poults.

Groups of broiler and layer type chickens (25 to 63 d.o.) were inoculated per os with separate isolates of 10 strains of Campylobacter jejuni. Nine of the 10 strains were originally isolated from chickens and one from a dog. The dog strain and five of the chicken isolates could be isolated after inoculation, but four strains were not recovered from cloacal swabs for up to 4 to 16 days after inoculation. However, it was possible to isolate C. jejuni from these birds, from cloacal swabs, when they were inoculated with organisms which had been previously shown to colonize other birds.

The minimum inhibitory concentrations (MICs) for valnemulin, tiamulin, enrofloxacin, tylosin, and lincomycin/spectinomycin were determined for a virulent strain of Mycoplasma gallispeticum (MG). At the initial reading, the lowest MICs were seen with valnemulin and tiamulin, followed by tylosin, enrofloxacin, and a relatively high MIC for lincomycin/spectinomycin. At the final reading, at 14 days, a similar pattern was obtained, with valnemulin giving the lowest MIC (< 0.008 mg/ml). The same strain of MG was used to infect groups of 20 2-day-old chicks in two separate experiments. In both, several concentrations of valnemulin and tiamulin and one each of tylosin and enrofloxacin were administered to separate groups in the drinking water. In the second experiment, one group of chicks was given lincomycin/spectinomycin. Each experiment had one infected unmedicated group and an uninfected unmedicated group. Mortality, clinical signs, and gross lesions, in both experiments, were significantly less (P < 0.001) in the uninfected and infected medicated groups (except for the two lowest dosages of valnemulin, lincomycin, and spectinomycin) than in the infected unmedicated groups. Also, the mean body weight gain was greater in the uninfected and infected medicated groups. Among the infected birds, MG was recovered from fewer chicks in the infected medicated groups except for the lowest two dosages of valnemulin. Serologic results were negative for the uninfected groups, and there were fewer positive reactors for the infected medicated groups except for the group treated with lincomycin/spectinomycin. Valnemulin should prove to be a useful addition to the antimicrobials in the control of MG infection in chickens.

Limulus amebocyte lysate (LAL) is activated by bacterial endotoxins and certain glucans (beta-D-glucan, LAL-RM). The potential for conflicting inter-laboratory results for LAL tests exists because commercial LAL reagents are highly variable in response to LAL-reactive glucans. The nature of beta-D-glucan activation of LAL and means for rendering LAL non-responsive to glucan are reviewed to provide a background for resolving conflicting data. Kinetic LAL methods are particularly useful for screening materials potentially contaminated with glucan. The presence of beta-D-glucan in parenterals is uncommon and is likely limited to products exposed to microbial or cellulosic materials. A scheme is suggested for identifying LAL-reactive glucans and for LAL release-testing without glucan interference.

The minimum inhibitory concentrations of tylosin tartrate and a new macrolid antimicrobial agent, tilmicosin, were assessed for six strains of Mycoplasma gallisepticum (MG) and three strains of Mycoplasma synoviae (MS) in vitro by the microbroth method. For four of the strains of MG, tilmicosin showed a slightly lower minimum inhibitory concentration (MIC) than did tylosin at both the initial reading (when pH 7.0 is first seen in the dilutions under test) and the final reading at 14 days of incubation. For one of the remaining strains, the MIC for tilmicosin was equal to or less than that for tylosin at the initial reading but greater at the final reading. For the other strain, the MIC for tilmicosin was greater than for tylosin, and for both of them the MICs were very much higher than for other strains. For the three strains of MS, there was little difference between the two drugs for one strain whereas the MIC for tilmicosin was slightly less for the other two groups. Groups of 30 chicks were infected with a virulent strain of MG and treated with either tylosin (0.5 g/liter) or tilmicosin (at concentrations of 0.125, 0.25 or 0.5 g/liter). One infected group was untreated and another group was uninfected and untreated. Clinical signs, mainly depression and nervous signs, were seen in two to five birds in the infected treated groups. In contrast, in the infected untreated group, 16 of 30 birds showed clinical signs. Mortality was significantly less in the infected treated groups compared with the infected untreated group (P < 0.001), and following infection there were significantly (P < 0.05) greater weight gains in the infected medicated groups. At necropsy the prevalence of gross lesions of the airsac walls was similar in all the infected medicated groups and was less than that for the infected unmedicated group. For the group on tylosin, MG was recovered from five chicks during life and from six dead chicks. The corresponding figures for the group receiving the lowest dose of tilmicosin were four for each; however, the organism was not recovered from the groups on the higher doses of tilmicosin either during life or from dead chicks. Serological results were negative for all groups except the infected untreated group, in which all three birds that were tested were positive.

Ducklings on a problem farm which showed persistent and unacceptably high mortality yielded a larger range and greater number of viruses than did ducklings from a second flock, in which mortality was of a power and acceptable level. Reoviruses were the viruses most frequently isolated from young birds from both farms, but for longer at the problem site. ELAs (Embryo Lethal Agents), named since they caused high mortality in chick embryos, but could not otherwise be characterized, were recovered frequently and throughout the growth cycle of the problem flock, but not at all in the other flock. Lentogenic Newcastle disease virus was detected at all ages on the problem farm but less often than ELAs. The faeces of birds on the problem farm yielded rota-like viruses, corona-like viruses and adeno-like viruses, and on the farm with normal mortality, Egg Drop Syndrome-76 virus and adenovirus. Detection techniques included culture on chick embryos and chick embryo liver cells, and electron microscopy (EM). Inoculation of whole eggs was particularly valuable and more successful than cell culture for virus recovery. EM was most useful for direct examination of faecal preparations and confirmation of the viral type.

In a preliminary experiment, a field infection with Mycoplasma iowae was simulated by inoculating turkey eggs with various doses of two strains of M. iowae immediately before incubation. The strain and dose chosen for further study were those that best multiplied and resulted in infection of embryos from which the organism could be isolated after 25 days of incubation. Ten turkey hens free from infection with mycoplasmae were housed in isolation. The hens were given enrofloxacin in the drinking water at a concentration of 50 ppm on 3 successive days, on two occasions at intervals of 14 days. Within 48 hours of lay, their eggs were each inoculated with 0.1 ml of the selected strain and dose (10(5) colony-forming units/ml) of M. iowae. M. iowae was recovered from almost all eggs laid by hens before the initial medication but not from any of the eggs laid for several days after each period of medication. Thereafter, the organism could be recovered from a high proportion of inoculated eggs. The treatment of infected turkey laying flocks with enrofloxacin at strategic periods might be helpful in the control of this Mycoplasma by limiting both vertical and horizontal transmission.

In the production of Mycoplasma gallisepticum (Mg) antigens for ELISA and microimmunofluorescence (MIF) tests, two strains of Mg, S6 and PG31, were grown in broth culture and harvested at intervals from 18 to 138 h. The effect of duration of incubation of culture on antigen sensitivity and specificity was assessed using homologous sera (against Mg S6), and sera prepared against Mycoplasma synoviae (Ms), and against mycoplasma media. It was found, in both Mg S6 and PG31 ELISAs, that in the period 18 to 70 h of incubation, sensitivity declined with homologous sera, but little thereafter. A more rapid and greater decline occurred with PG31 antigen than S6. The antigens showed a lack of specificity since antisera to Ms gave positive reactions. These were not influenced by duration of incubation of Mg culture. In the Mg S6 ELISA lack of specificity was also shown by positive reactions with sera against media components. These increased in the first 42 h of cultivation. In the MIF test there was no loss of sensitivity with Mg S6 antigen with increasing duration of incubation of culture but it occurred with PG31 antigen. The non-specific reactions with antisera to Ms increased with increased duration of incubation of both strains of Mg. This work demonstrates that the most sensitive antigens are produced by harvesting organisms early in culture, although this does not eliminate the Ms cross reactions.

Groups of chicks were infected with a virulent strain of Mycoplasma gallisepticum (MG) and treated with either danofloxacin or tylosin while one infected group was left untreated and a further group was uninfected and untreated. Control of clinical signs and mortality was better with danofloxacin than tylosin and there was significantly (P < 0.05) greater weight gain with danofloxacin at 21 days after infection. However at necropsy the prevalence of lesions of the airsac walls was similar in both groups. MG was recovered from fewer live chicks for the first week following treatment with danofloxacin, but at 2 weeks and at necropsy, at the termination of the experiment, it was recovered from a similar proportion of birds in both treated groups. This was reflected also in the serological results at the end of the trial.

Mature laying chickens were inoculated intratracheally with a field strain of infectious laryngotracheitis (ILT) virus. Tracheal swabs were collected regularly from all birds for virus culture. At various times post-inoculation, pairs of birds were killed and tissues removed for detection of virus products using conventional tissue homogenization and culture, organ culture, indirect immunofluorescence (IF) and also the polymerase chain reaction (PCR). The latter was used to detect a DNA sequence from the ILT virus thymidine kinase gene. Following inoculation the birds developed mild respiratory disease with clinical signs characteristic of ILT from 3 to 10 days post-inoculation. Trachea and turbinate tissues were virus-positive as determined by virus isolation, organ culture, IF and PCR on day 4 post-inoculation. After recovery from the acute phase, virus shedding initially ceased, then intermittent, low level shedding was recorded for five of the six remaining birds. In an attempt to locate sites of latency, pairs of birds were sampled at 31, 46 and 61 days post-inoculation. Virus was not detected in upper respiratory tract or ocular tissues by conventional techniques, or in the trigeminal, proximal and distal ganglia. All tissues were also negative by PCR, except for the trigeminal ganglia of five of the six birds. All PCR-positive birds had previously shed ILT virus intermittently between days 19 and 59 post-inoculation. As we did not detect viral DNA in any of the other tissues sampled from clinically recovered birds, we conclude that the trigeminal ganglion is the main site of latency of ILT virus.

In an attempt to produce a persistent infection with M. iowae (Mi) three separate trials were conducted using strain B 11/80, a virulent strain, strain M 012-118, a recent isolate of unknown virulence, and strain Iowae 695 (I 695), the type strain. In each trial groups of 2-day-old poults were infected via the oesophagus, trachea, cloaca and directly into the lungs. Isolation during life was attempted from the oropharynx and the cloaca, and at necropsy at the end of the experiment (21 days after infection) from the trachea, lungs and airsacs, and the brain. The highest proportion of isolations were made at necropsy from the lungs and air sacs, and trachea, from birds infected with B 11/80 or M 012-118 via the lungs or B 11/80 given via the trachea. During life the proportion of isolations was lower than at necropsy but highest, overall, with B 11/80 given via the lungs or trachea and isolated from the oropharynx, or administered via the cloaca and isolated form this site. Strain I 695 was rarely isolated whatever the route of infection. There were few recoveries following infection via the oesophagus with any strain and no mycoplasmas were isolated from the brain. For the production of MI infection suitable for monitoring antimicrobials in young poults we would recommend infection with a pathogenic strain of the organism directly into the lungs.

Groups of specific pathogen-free chickens were inoculated with the same dose of a field strain of infectious laryngotracheitis virus that had either been isolated from tracheal swabs taken from infected birds during acute phase shedding, or that had been isolated during an episode of virus shedding after a latent period of 12 to 17 weeks. Birds in both groups developed characteristic clinical signs of ILT including difficulty in breathing, rales and sneezing. Thus, ILT virus shed after a latent period is capable of causing disease in susceptible birds similar to that seen in the field.

Field outbreaks of infectious laryngotracheitis in commercial chicken flocks in England and Wales between 1985 and 1988 were investigated. Material from 49 outbreaks was submitted to Liverpool University, and virus was isolated from 17 of them. The results of a questionnaire on each outbreak are described. Generally, the disease was of moderate severity, and mainly affected laying flocks; it occurred in birds of a wide age range but most of the outbreaks were in birds between 10 and 20 weeks of age. The disease was not seen more frequently at any particular time of the year, and there was no evidence of a common source of infection. Three of the affected flocks had recently been moved and were beginning to lay; these stresses may have caused the re-excretion of latent virus.

Comparison was made of the protection afforded by Baytril, Tylosin and Tiamulin for turkey poults infected with Mycoplasma iowae (MI) by injection of the organism into the lungs. Poults were infected at 2 days of age and treatment commenced 3 days later by including the appropriate drug in the drinking water. Following treatment with Baytril at 50 mug/ml for 5 days, MI was not isolated at 7, 14 and 19 days after infection from the oropharynx or cloaca, during life, but was recovered from five of 23 poults at necropsy. With the same concentration of Baytril, but for only 3 days, isolations of MI were made at 19 days post infection from the oropharynx and cloaca, from 2 of 23 live birds, but at necropsy at this time from 19/23 birds. From poults given Tylosin or Tiamulin (at 500 and 250 mug/ml respectively for 5 days) MI was isolated from a proportion of birds on all occasions during life, after infection, and from 19/21 and 18/21, respectively, at necropsy.

Latency and reactivation of a commercial infectious laryngotracheitis virus vaccine were demonstrated in live chickens. Virus was re-isolated at intervals between seven and fourteen weeks post-vaccination and this may be of epizootiological significance.

Two groups of day-old ducklings were infected with Mycoplasma gallisepticum and M anatis respectively by air sac inoculation. Clinical disease was not produced but air sacculitis was produced by both infections. M gallisepticum could be recovered readily from respiratory tissue 10 and 30 days after infections but RSA tests were negative. M anatis was not reisolated from these tissues or from the cloaca but a positive RSA test was observed on the serum of a few ducklings.

M. gallisepticum, M. synoviae and M. meleagridis are pathogenic strains of avian mycoplasma. M. gallisepticum and M. synoviae affect the chicken and turkey while M. meleagridis is associated with disease in the turkey. The tissues affected and the lesions are described and the influence on disease production of certain factors is considered. They include the age of the host, route of infection, numbers and virulence of organisms and predisposing and debilitating factors. The mechanism of pathogenesis is also indicated and reference made to a method of determining virulence.

Fifty-nine papillotomies were performed, 56 for biliary tract disease and three for papillary stenosis (secondary to carcinoma in two cases). All 56 patients with biliary tract disease had undergone previous cholecystectomies. Fifty-one of them had stones in the common duct, and in 41, all identified stones were removed. Stones were retained in ten patients, four of whom required surgical biliary tract exploration for extraction. Our results indicate that common bile duct stones with diameters 2.5 cm or greater should be approached surgically. Endoscopic papillotomy had an initial success rate of 80% for extraction of common bile duct stones and a late or actual success rate of 92%, confirmed by cholangiography. There were nine complications, including five episodes of bleeding (three requiring surgical intervention for control), giving an overall morbidity rate of 15.2%. The mortality was 3.4%. The procedure is indicated in the treatment of papillary stenosis and stones retained in the common bile duct after cholecystectomy.

Extracapsular hemorrhage from spontaneous rupture of a hyperplastic parathyroid gland is exceedingly rare. Rupture of an intrathoracic parathyroid adenoma mimicking a dissecting thoracic aortic aneurysm has been reported in two cases. Hypercalcemic crisis associated with contained hemorrhage within a parathyroid adenoma has been well documented. We present the first reported case of spontaneous rupture and extracapsular hemorrhage of a cervical parathyroid adenoma. Serum calcium levels should be obtained when spontaneous cervical or mediastinal hemorrhage develops without obvious cause.

In turkey poults aged up to 28 days, a virulent S6 strain of M. gallisepticum was recovered more frequently from more tissues for a longer time than were other strains. The virulent strain caused nervous signs and gross brain lesions in poults, and was often isolated from the brain, suggesting its neurotropism. All M. Gallisepticum strains were isolated from the synovial fluid of hocks, but swollen hocks and foot pads were seen only in poults infected with the A514 strain. It would seem, therefore, that although proclivity for joints was shown by all strains, only A514 produced grossly pathogenic effects in these young birds. All strains of M. gallisepticum showed some proclivity for respiratory tissues. Signs, gross lesions and recoveries of mycoplasma frequently failed to correlate. Perosis was seen in only two poults; these were infected with M. gallinarum with which the condition may, or may not, be associated. Serological reactions to both the rapid serum agglutination and haemagglutination inhibition tests developed in the 3rd and 4th weeks of life in all poults infected with M. gallisepticum strains although false positives and negatives were recorded. The main results of infection with the strains in turkey poults and in a similar study in chicks are summarised.

The mycoplasma infecting and sometimes causing disease of the respiratory system in both species are M. gallisepticum and M. synoviae, while M. meleagridis affects the turkey only. M. gallisepticum has received the greatest attention and natural infection is reported to result in protection varying greatly in degree and duration. Vaccination with living organisms either by the respiratory or intravenous routes results in a high degree of protection against air sac challenge for at least a few weeks. Killed organisms administered intravenously result in a lesser degree of protection to this challenge but when given intranasally provide no protection. M. gallisepticum survives in the respiratory tract and perhaps in other organs and tissues for long periods after infection, perhaps in latent form. However, intercurrent infection and other avian respiratory pathogens may precipitate multiplication of the organism and disease in birds apparently resistant to challenge with mycoplasma alone. The mechanism of protection has not been extensively studied and production and significance of local antibody or a cell-mediated response have not been determined. However, bursectomized chickens vaccinated against M. gallisepticum show much less resistance compared with controls but the exact part played by humoral antibody is still in doubt. Similar observations have been made with M. synoviae.

This study was made because of the difficulty of resuscitating Mycoplasma meleagridis from agar cultures received from the field. The type strain of Mm was found viable following culture at 37 degrees C for as long as 10 days and maintenance at room temperature for a further 14 days but only when few colonies were present in the original culture. It is suggested that for the satisfactory subculture of this organism the original culture on mycoplasma agar should not exceed 1 week, or no more than a few days should the colonies appear after this time, and that the period at room temperature should also not exceed 1 week. Non-viable colonies, if small, may however be recognised by immunofluorescence.

Mycoplasma gallisepticum, Mycoplasma synoviae and Mycoplasma meleagridis are the most widespread pathogenic poultry mycoplasmas. The epidemiology of the infections, and clinical signs, lesions, pathogenesis, diagnosis and control of disease are described. In epidemiology, the constant antigenic composition, variation in virulence, tropism, survival of the mycoplasma outside and within the host and susceptibility to drugs are outlined. The significance of species, age and immune status of the host and the importance of intercurrent infection and debilitating factors in the production of disease are given. The transmission of infection, clinical signs of disease, and gross and histopathological appearances of lesions are described. The interpretation of the pathogenesis of disease is based on the appearance of lesions in untreated birds and in bursectomized or thymectomized chickens. The means of recognizing infection, and the methods used in ameliorating the worst effects of disease or eradicating infection follow.

Five groups of turkey hatching eggs from two mycoplasma infected flocks were subjected to preincubation heating in an attempt to eliminate mycoplasma, particularly M. meleagridis. The eggs were heated over 11.5 to 12.5 hours with a linear increase in temperature from approximately 25 degrees C to mean maxima ranging from 46.2 degrees C in one trial to 47.6 degrees C in the fifth trial. Both untreated control eggs and preheated eggs were then conventionally incubated and at hatching live poults were killed. Recovery of mycoplasma was attempted from pools of respiratory tract, cloaca and yolk which were made separately from each group. Whilst M. meleagridis was isolated from 13 of the 15 tissue pools of the control poults, it was only recovered from five of the pools from preheated eggs and not from any in the two trials at the higher temperatures. Nevertheless, other mycoplasma were recovered from the two groups at these temperatures but not from all the tissues. At the higher maximum temperatures also there was a very significant reduction in hatchability.

During the past five years, 65 patients with Hirschsprung's disease have been treated at our institution. Ten of these patients had long-segment aganglionosis, five with total colonic involvement, four with aganglionosis to the midtransverse colon, and one child with Hirschsprung's disease extending to the distal jejunum. There are six females and four males in the series, which is a reversal of the normal sex ratio for aganglionosis. An extensive literature review of long-segment Hirschsprung's disease has revealed a total of 489 reported cases. The mean frequency of long-segment aganglionosis in the literature is 12% of all cases of aganglionosis. Our series is comparable, with an incidence of 15%. The overall mortality rate in the literature of 54% indicates the poor therapeutic results obtained with this disease in the past. All ten of our patients have been definitively treated with a modified endorectal pull-through procedure. The mortality rate with this procedure has been zero. There has been one major complication (incorrect pathologic diagnosis of the level of aganglionosis) and four minor complications. The average follow-up period is 42.6 months. The functional results have been excellent with an average of three to four soft bowel movements per day. All of the children over 3 years of age are completely toilet trained. The remaining two patients are too young to be toilet trained, but are continent in the sense that they do not soil between bowel movements. Awareness of this entity of long-segment aganglionosis should lead to earlier diagnosis, appropriate operative therapy, and lower mortality rates.

An unusual case of an internal hernia related to a retropubic femoral-femoral bypass graft is presented. An orifice between the left and right inguinal ligaments and a protruding intraperitoneal portion of the prosthetic graft material resulted in herniation and strangulation of a portion of the small intestine. Technical factors (graft redundancy or misplacement) and natural factors (pulsatile erosion or age elongation) may be implicated. The potential for this complication exists in all grafts currently placed. The subcutaneous location appears to be a better technique.

Three strains of M. gallisepticum comprising S6 of low passage (virulent), S6 of high passage and A514 of high passage in artificial media and one M. gallinarum strain of high passage, were inoculated into 18-day-old chick embryos. Four groups of infected chicks hatched, one corresponding to each mycoplasma strain; these were investigated during the first 28 days of life and again for a period in lay. During the first 28 days of life, the virulent S6 strain was recovered more frequently from a wider variety of tissues for a longer time than were the other two strains of M. gallisepticum; this strain also produced more severe clinical disease including nervous signs, respiratory lesions and swollen hocks. Although nervous signs were confined to birds infected with the virulent S6, both S6 strains were isolated from brains and hocks, suggesting this strain's proclivity for these sites. One A514 infected chick developed unilateral eye enlargement from which mycoplasma were isolated. All strains of mycoplasma were isolated from respiratory tissues, indicating a proclivity common to all. Recoveries of mycoplasma were often associated with signs and/or lesions but not always, and recoveries also occurred in the absence of signs and lesions. M. gallinarum caused no clinical signs or lesions in young chicks and was rarely isolated. In mature birds, mycoplasma were isolated from the respiratory tissues of some infected with either of the two S6 strains or with M. gallinarum, but not from A514 infected chickens. In both younger and mature chickens, mycoplasma were most likely to be recovered from respiratory tissues and the infra-orbital sinus. Most chicks infected with the virulent S6, showed positive haemagglutination inhibition (HAI) reactions from 4 days of age which preceded the rapid serum agglutination (RSA) reactions. In contrast, chicks infected with other strains of M. gallisepticum either showed no positive HAI reactions, or developed them after 21 days. In either case, positive RSA preceded HAI reactions. The numbers of mature birds examined were small, but, comparing isolation of M. gallisepticum with serological results, it appears that false positives occur with the RSA and both false positives and negatives with the HAI test. No egg transmission of mycoplasma was observed.

The minimum inhibitory concentration (m.i.c.) of kitasamycin, tylosin and tiamulin for Mycoplasma gallisepticum (Mg) were compared with 10(6), 10(4), and 10(2) CFU/ml of the organisms with the drug incorporated in mycoplasma agar. The lowest m.i.c. was obtained with tiamulin and the highest with kitasamycin and, in general, the m.i.c.'s were directly influenced by the concentration of mycoplasmas. Chick embryos at 19 days of incubation were infected with Mg and the hatched infected chicks were used for comparing the protective effect of the three drugs. They were given in the drinking water when the chicks were 2, 3 and 4 days of age. Weight gains for the infected treated birds were similar for all three drugs; they were significantly lower than for those of uninfected chicks and significantly higher than for those of untreated infected chicks. However Mg could be isolated from a high proportion of chicks in the infected treated and untreated groups at 32 days of age.

Mycoplasmaa-induced arthritis of poultry under field conditions is almost entirely caused by Mycoplasm synoviae (Ms) infection. Experimentally, Mycoplasma synoviae, Mycoplasma gallisepticum, Mycoplasma meleagridis and Mycoplasma iowae have all been shown to cause arthritis, tenosynovitis and lesions of periarticular tissue. However, greatest attention has been given to Ms in this respect. The leg joints are most consistently involved, and of these particularly the tibiotarsal-tarsometatarsal and tarsometatarso-phalangeal joints. Acute amd chronic arthritis have been described, and in the later the arthritic lesions may be progressive. The histopathological changes include invasion with heterophils (polymorphs) and later monocytes. Villus formation is shown by the synovium, and lymphofollicular aggregates appear. In severe cases, there is progressive erosion of articular cartilage and there are degenerative changes in underlying bone. Systemic changes include anemia, reticulitis, arteritis, and atrophy of the thymus and bursa of Fabricius. The mechanism of disease production may involve a direct inflammatory response as well as immunoinflammatory complexes.

Fifty-six patients, ranging in age from 49 to 90 years, underwent abdominal aortic aneurysmectomy and had cultures taken from the aneurysm wall and atheromatous debris to identify possible microbiological sources of future graft infection. All patients received antibiotics before and after operation. Eleven (19.6%) of 56 cultures yielded bacterial growth. The most common organism isolated was Staphylococcus epidermidis (in six of 11 patients). Thirty-seven percent of the aneurysms cultured were symptomatic (expanding or ruptured); however, this group accounted for 54% (6/11) of the positive cultures. During an average follow-up period of 24.5 months (range, four to 82 months), no early or late graft infections were documented. A literature review demonstrated the same disparity between positive cultures obtained at aneurysmectomy and subsequent low graft-infection rate.

Between June 1977 and November 1981, 26 children and adults with ulcerative colitis have undergone a total colectomy, an endorectal dissection of the rectal mucosa, and an ileoanostomy. A combined abdominoperineal approach was used to perform the operation, and the mucosal-submucosal rectal tube was dissected out intact from the abdominal approach. Every patient survived the operation and showed marked clinical improvement presumably due to resection of the diseased colon. Three patients developed intestinal obstruction that was successfully treated with an enterolysis. A rectal cuff abscess and a retroperitoneal abscess were the only other complications. The postoperative stooling pattern of each patient was obtained through detailed interviews. All the patients were continent during the day and at night one month after surgery. Twenty-two patients had a median stool frequency of seven per 24 hours one month after surgery. At one year, the average number of stools was seven per day. Six patients experienced a stool frequency of seven per 24 hours two years after surgery. The results with this series of patients had encouraged the authors to continue to recommend this approach to children and adults with ulcerative colitis, since it offers an alternative lifestyle that is more attractive to certain patients than the presence of an abdominal stoma.

Depression and ataxia was seen in 24-day-old chicks accidentally fed excess zoalene from 14 days of age. The presence of a small amount of furazolidone in the ration probably exacerbated the effect. There were no deaths. No other causes could be found for the condition and replacing the rations with food containing less than the recommended level of zoalene and no furazolidone resulted in recovery within 4 to 5 days. In an experimental study the syndrome was reproduced in baby chicks with as little as 2(1/2) times the recommended level of zoalene in the food. Increasing the amount of zoalene hastened the onset and increased the severity of symptoms and markedly depressed weight gains; the addition of a small amount of furazolidone had a synergistic effect. Inappetance may be largely responsible for the depression in weight gain, and damage to Purkinje cells seems to account for the ataxia and nervous signs. In laying birds 10 times the recommended level of zoalene in the food over 30 days caused inappetance, cessation of egg production, and progressive weakness, but no nervous signs.

Comparison was made between direct plating onto mycoplasma agar and culture in overlay or broth in the recovery of mycoplasma from avian field material from poultry, wild and exotic birds. The value of an atmosphere of increased carbon dioxide, provided by 5% carbon dioxide in nitrogen or by 'candle jar', and of 'restreaking', was also investigated. From a total of 1784 tissues examined in four experiments mycoplasma were recovered from 463 involving 509 strains. Of these strains, 73% were grown by direct plating, 82% by a combination of subcultures from overlay and fewer by the individual overlay subcultures. A proportion of recoveries was made by each method alone. Recovery of mycoplasma through culture in broth was markedly inferior to either direct plating or overlay culture. There was no apparent advantage in incubating mycoplasma plates in an atmosphere of increased carbon dioxide. Restreaking increased recoveries by only a small number. The mycoplasma recovered included the following recognised avian species or serotypes:- M. gallisepticum, M. gallinarum, serotype D, M. iners, sero-type F, M. meleagridis, serotype I, M. synoviae, M. anatis, A. laidlawii, and a number of untyped strains especially from exotic birds. Combinations of two or more serotypes were also isolated from approximately 10% of the tissues from domestic poultry. Although most serotypes were isolated by both direct plating and overlay methods, the recovery of serotype I and M. meleagridis seemed to be favoured by direct plating while M. gallisepticum and a number of untyped organisms were more frequently isolated after culture in overlay. The only organism recovered by one method alone was serotype D (from overlay) but only three recoveries were made. In the examination of avian tissue using conventional media it would seem that for maximum recovery of mycoplasma direct plating together with subcultures from overlay could be recommended. Incubation of plates in additional carbon dioxide seems unnecessary and 'restreaking' is of limited value.

Tissues of mycoplasma infected chicks and turkey poults were cultured and subcultured on mycoplasma agar. Usually, colonies which grew on the agar initially inoculated could be subcultured, but sometimes they could not. At other times, colonies were not seen on the agar initially inoculated but appeared on the subcultured plate.

A survey of mycoplasma infections of chickens, turkeys and ducks was made on tissues from a variety of sources and birds of various ages, and from pipped and dead-in-shell turkey embryos. The tissues examined consisted mainly of respiratory tissue and the cloaca and contents and also a small number of joint lesions and other tissues. From chickens, mycoplasmas were isolated from a total of 138 tissues with Mycoplasma gallisepticum in preponderance. This was followed by M gallinarum, untyped organisms, M synoviae and a number of other mycoplasmas and Acholeplasma laidlawii. From turkeys, poults and embryos, mycoplasmas were recovered from 164 tissues with M meleagridis in preponderance. This was followed by M gallisepticum, serovar I, M synoviae and a number of other species including untyped isolates. From ducks, M gallisepticum and M anatis were recovered in equal numbers. Mycoplasma infections with more than one species occurred in the same tissue in all species of stock but especially in turkeys.

High mortality rates reported with common bile duct exploration (CBDE), 3.4 per cent to as high as 30 per cent in re-exploration of those over 70 years of age, prompted review of endoscopic papillotomy (EP) for stone extraction in a community hospital as well as an attempt to assess its impact on the treatment of common duct stones. Endoscopic papillotomy in 237 patients had a 1.3 per cent mortality. Successful extraction of the stone occurred in 91.6 per cent of 108 patients followed for at least 2 years with no further treatment required. Morbidity and mortality was uneffected by previous biliary surgery, repeat attempts at stone extraction or EP performed prior to cholecystectomy (P greater than 0.1). The results of treatment for choledocholithiasis in 111 consecutive patients was then retrospectively reviewed to assess the impact of endoscopic papillotomy. CBDE was used initially in 79 and EP in 32 patients. Previous cholecystectomy and age biased the selection for endoscopic papillotomy (P less than 0.01). The mean ages were 57.8 years and 70.6 years (P less than 0.01), for CBDE and EP pts respectively. Age adjusted hospital stay was significantly longer for common bile duct exploration (P = 0.002). Overall, morbidity was not different between the treatment modalities (P = 0.50) and each group had one death (P = 0.23). In this community hospital, endoscopic papillotomy is safe, effective, and was reserved mainly for older patients or those with prior cholecystectomy and choledocholithiasis.(ABSTRACT TRUNCATED AT 250 WORDS)

A number of sera from turkeys considered to be uninfected with Mycoplasma iowae were examined by indirect ELISA using whole cell Ai. iowae serovar I antigen. In an attempt to reduce the number of 'false positive' sera, assays were made (a) using plates blocked with foetal calf serum or skim milk before, or, bovine serum albumin after, coating with antigen, (b) using the absorbance difference method in which each serum was tested against mycoplasma antigen and medium antigen and (c) with unblocked plates but with serum heated to 56 C for 30 min. The upper limit of absorbance for the negative sera was determined using formulae already used by others including, the mean plus twice the standard deviation, the mean plus three times the standard deviation, (M + 3SD), twice the mean, 115% of the mean and four times the standard deviation. Some reduction in the number of 'false positive' sera occurred after heating sera or using the formula of M + 3SD. This formula might, however, reduce the sensitivity of the test.

Experiments were set up to assess the effects of 'natural' and 'artificial' stresses on the re-excretion of infectious laryngotracheitis (ILT) virus in latently infected chickens recovered from the acute phase of the disease. The stresses were rehousing with the addition of ILT-free contact birds, corticosteroid treatment and the onset of lay. The contact birds were also monitored for transmission of the virus from the carrier birds. Rehousing with unfamiliar birds induced ILT virus shedding in one of five birds and there was evidence of transmission from this bird to its mate. The onset of lay had a significant effect on the overall shedding rates of the carrier birds. Nine of 10 birds shed virus after onset of lay compared with only two in the three-and-a-half weeks before, and there was a highly significant increase (P less than 0.001) in the overall number of virus isolations during this period. Corticosteroid treatment did not affect virus shedding. These results may explain some of the apparently spontaneous outbreaks of ILT which occur in the field.

During the past 4 yr, 60 patients with Hirschsprung's disease have been treated at our institution. Twenty-eight patients within this group have undergone a modified endorectal pull-through procedure. There are 18 males and 10 females in the series. There are 5 children with total colonic involvement, 3 patients with aganglionosis to the mid-transverse colon, and one child with Hirschsprung's disease extending to the distal jejunum. The associated anomalies have consisted of four cases of Down's syndrome, one of whom also has transposition of the great vessels. There has been no operative-related mortality or late mortality in our series. Two major complications (anastomotic leak following a colostomy closure and incorrect pathological diagnosis of aganglionic level) and five minor complications have occurred. The average follow-up period is 31.3 mo. The functional results postoperatively have been excellent. The 18 patients over the age of 3 yr are completely toilet-trained. The remaining patients are too young to be toilet-trained, but are continent in the sense that they do not soil between bowel movements. Because of the satisfying functional results in this series, we have now expanded our indications for this procedure to patients requiring total colectomy for ulcerative colitis and familial polyposis. During the past 2 yr, 8 patients with ulcerative colitis have undergone the endorectal pull-through together with a total colectomy.

We studied a patient with rectal gastric heterotopia and found nine reported cases of this rare disease in the literature. Symptoms include proctitis and rectal bleeding. Heterotopic gastric epithelium may be developmental or acquired, depending on the type of mucosal epithelium involved. Since this type of lesion can occur anywhere in the alimentary tract and even in multiple sites, long-term follow-up is recommended. The diagnosis is made by biopsy and pathologic examination. The treatment consists of total local excision. Sigmoidoscopy, colonoscopy, and technetium scanning can be used as adjunctive aids in diagnosing secondary sites of gastric heterotopia.

The standard surgical approach to multiple polyposis has been a total proctocolectomy and an end ileostomy because of the premalignant nature of the disease. This operation has been successful, but has resulted in a significant amount of psychological trauma due to the presence of an abdominal stoma. For that reason, we have utilized the sphincter-saving operation, namely, the endorectal pull-through for the definitive management of patients with familial polyposis since 1979. During the years 1979 to 1984, seven patients (4 female and 3 male), ranging in age from 10 to 30 years, have undergone an endorectal pull-through at our institution. Four of these patients had previously undergone a subtotal colectomy and ileoproctostomy and were seen because of persistent polyps in the remaining rectum. The operation consisted of a total colectomy, a mucosal proctectomy, an ileoanostomy and a loop ileostomy (1 patient did not undergo a loop ileostomy). The loop ileostomy was closed about two months after the pull-through procedure. There was no mortality and only one complication was seen postoperatively. This complication consisted of a bowel obstruction one week after ileostomy closure which was successfully treated with an enterolysis. Patient satisfaction has been excellent. All patients have either returned to full-time work or full-time school activity. All were completely continent immediately after ileostomy closure, both during the day and at night. The median stool frequency one year after the operation is five stools per 24 hours. Our results with this operation have encouraged us to recommend the endorectal pull-through to all patients with multiple polyposis.