First Occurrence of Anthracnose Caused by Colletotrichum gloeosporioides on Pitahaya.

Pitahaya, Hylocereus undatus Britt. & Rose, is a columnar, climbing cactus that produces a commercially important fruit. In December 2004, a new disease was found on the crop in Miami-Dade County, FL. Reddish brown lesions with conspicuous chlorotic haloes developed concentrically on the edges of vine ribs. Lesion centers became white and coalesced to rot much of the vine column, and in severe cases, only the vascular column in the vine center was not diseased. Salmon-colored spores and waxy, subepidermal acervuli, typically with setae and simple, short, erect conidiophores, were observed in lesion centers. Tissue from lesion margins was surface disinfested and plated on potato dextrose agar (PDA; Difco Laboratories, Detroit, MI). Colletotrichum gloeosporioides (Penz.) Penz. & Sacc. was isolated from all samples. Colonies produced abundant conidia that were hyaline, one celled, straight, cylindrical, and averaged 14.7 × 5.0 µm with ranges of 12.5 to 17.5 × 3.8 to 7.5 µm (1). Cultural and morphological characteristics of isolates matched those for C. gloeosporioides except for appressoria and hyphopodia (1,2); pitahaya isolates had a spherical rather than lobed hyphopodia reported for C. gloeosporioides and averaged 10.9 (8.5 to 12.7) × 9.1 (7.1 to 10.3) µm. Internal transcribed spacer sequences for the pitahaya isolates were nearly identical (98% homology) to those for C. gloeosporioides isolates occurring on Euphatorium thymifolia in Thailand (GenBank Accession No. AY266393). Koch's postulates were examined in greenhouse trials at the Tropical Research and Education Center, Homestead, FL. Treatments consisted of a noninoculated control, four C. gloeosporioides isolates, and an Alternaria sp. All isolates came from symptomatic pitahaya tissue collected in Miami-Dade County. Fungi were grown on PDA for 7 days at 27°C. A sterile dissecting needle was used to gently pinprick the epidermis of the stem and 2-mm-diameter plugs of C. gloeosporioides, an Alternaria sp., or clean PDA were placed over wounds. Plants were placed in a plastic tent in a greenhouse where the temperature was held at 25°C, and free moisture was maintained on plant surfaces with a household humidifier for 48 h following inoculation. Two isolates of C. gloeosporioides were shown, in repeated greenhouse experiments, to cause reddish brown lesions with conspicuous chlorotic haloes that coalesced to rot much of the vine column, and Koch's postulates were completed with the reisolation of isolates that were used to inoculate plants. The age of vine segments had no significant effect on lesion development. To our knowledge, this is the first report of C. gloeosporioides as a pathogen of pitahaya. References: (1) J. A. Bailey and M. J. Jeger. Colletotrichum: Biology, Pathology and Control. CAB International, Wallingford, UK, 1992. (2) M. Du et al. Mycologia 97:641, 2005.

Attractiveness of Host Plants at Different Growth Stage to Kudzu Bug, Megacopta cribraria (Heteroptera: Plataspidae): Behavioral Responses to Whole Plant and Constitutive Volatiles.

The kudzu bug, Megacopta cribraria (Fabricius), is an invasive pest of soybeans, Glycine max (L.) Merr., that has recently been detected in the United States. This study investigated whether there was a differential attraction of adult bugs to soybean growth stages, and whether the attraction was related to soybean constitutive volatiles. Greenhouse choice assays examined the behavioral orientation preference of adult bugs exposed to four growth stages of whole soybean plants: vegetative (V2), flowering (R1), pod (R3), and seed (R5). Results show that significantly more adults landed on plants in the early reproductive stage R1 than in other stages. Laboratory olfactometer assays also demonstrate that significantly more adult bugs were attracted to R1 plants, with females responding more strongly than males. Both greenhouse and olfactometer assays indicate that the differential attraction of adult bugs to soybean growth stages was mediated by plant constitutive volatiles. These results offer an insight into kudzu bug chemical and behavioral ecology and thus are of great significance for optimizing the timing of field scouting and treatment as well as the development of soybean pest management programs.

Experimental transmission of Corynebacterium pseudotuberculosis biovar equi in horses by house flies.

BACKGROUND: The route of Corynebacterium pseudotuberculosis infection in horses remains undetermined, but transmission by insects is suspected. OBJECTIVES: To investigate house flies (Musca domestica L.) as vectors of C. pseudotuberculosis transmission in horses. ANIMALS: Eight healthy, adult ponies. METHODS: Randomized, controlled, blinded prospective study. Ten wounds were created in the pectoral region where cages for flies were attached. Three ponies were directly inoculated with C. pseudotuberculosis. Four ponies were exposed for 24 hours to 20 hours C. pseudotuberculosis-inoculated flies. One negative control pony was exposed to noninoculated flies. Ponies were examined daily for swelling, heat, pain, and drainage at the inoculation site. Blood was collected weekly for CBC and biochemical analysis, and twice weekly for synergistic hemolysis inhibition titers. RESULTS: Clinical signs of local infection and positive cultures were observed in 7/7 exposed ponies and were absent in the negative control. In exposed ponies, peak serologic titers (1:512 to 1:2,048) were obtained between days 17 and 21. Seroconversion was not observed in the negative control. Neutrophil counts were higher in the positive and fly-exposed groups than in the negative control (P = .002 and P = .005) on day 3 postinoculation. Serum amyloid A concentrations were higher in the positive control than in the negative control and fly-exposed ponies on days 3 (P < .0001) and 7 (P = .0004 and P = .0001). No differences were detected for other biochemical variables. CONCLUSIONS AND CLINICAL IMPORTANCE: House flies can serve as mechanical vectors of C. pseudotuberculosis and can transmit the bacterium to ponies.

Validation of saliva sampling for total body water determination by H2 18O dilution.

The use of saliva sampling for the measurement of total body water by H2 18O stable isotope dilution was assessed. The H2 18O abundance in saliva reached a constant value by three hours after isotope administration, and the total body water calculated from the 3-h saliva values was not significantly different from the value calculated from the 4- and 6-h serum samples. The results indicated that isotopic equilibration between these fluids was rapid and complete. Comparison of total body water calculated from the paired serum and saliva studies indicated that the relative precision of the determination was between 0.8 and 1.5%. Saliva sampling is noninvasive and is well suited for use in children in field studies.

Total body water measurement in humans with 18O and 2H labeled water.

Deuterium or tritium labeled water traditionally has been used for the measurement of total body water by application of the dilution principle. However, these methods have not enjoyed wide clinical use. The use of deuterium is hampered by the tedious and time consuming nature of the analysis while the use of tritium involves a radiation hazard. In addition, exchange of the label with nonaqueous hydrogen in the body raises questions about the accuracy of total body water values. To determine if water labeled with the stable isotope 18O can yield faster and more accurate results, total body water was measured simultaneously using water labeled with both 18O and 2H. The 18O and 3H dilutions were measured by mass spectrometry. The relative precision of the body water value using the 18O method was 2% for both serum and breath analysis. The 18O was fully equilibrated within 2 to 3 hr after administration, and results from the analysis of breath CO2 could be readily obtained within 1 hr after sampling. The H2(18)O dilution space averaged 3.0% (SE = 0.4) less than the 2HHO dilution space, because the latter exchanges with nonaqueous hydrogen. For this reason, the H2(18)O dilution should be a more accurate measure of total body water than the 3HHO dilution.

Breaking of scored tablets: a review.

The literature was reviewed regarding advantages, problems and performance indicators of score lines. Scored tablets provide dose flexibility, ease of swallowing and may reduce the costs of medication. However, many patients are confronted with scored tablets that are broken unequally and with difficulty, reducing compliance and reliance on the drug. Possibilities to reduce breaking difficulties are breaking instructions, tablet-splitters and breaking in advance. Factors influencing the performance of score lines are shape, size, curvature and thickness of the tablet and the form and deepness of the score line. Performance of score lines can be defined by breaking ease, uniformity of mass of subdivided tablets and loss of mass by the subdivision. For breaking ease, an in-vivo reference test and a routinely applicable in-vitro test need to be established. For the uniformity of mass of subdivided tablets a requirement has recently been set by the European Pharmacopoeia. Loss of mass upon breaking can be limited to not more than 1%.

Occurrence of Nigrospora Lint Rot Caused by Nigrospora oryzae on Cotton in Alabama.

During 2000 and 2001, a lint rot of cotton bolls (Gossypium hirsutum L.) was reported in the coastal region of Alabama when precipitation was 55% lower than the 5-year average. Bolls at an early stage of opening contained gray mycelium within the locules. At maturity, the lint within the infected locules was discolored, and the fibers were compact resulting in the characteristic "gray lock" sign and symptom attributed to Nigrospora oryzae (Berk. & Broome) Petch. Roots, petioles, leaves, and bolls when present were sampled at the seedling, first bloom, full bloom, and maturity stages of cotton development. A total of 640 sections of tissue (approximately 5 mm2) were surface sterilized for 20 s in 95% ethanol followed by 60 s in 0.525% NaOCl and aseptically plated on potato dextrose agar. Plates were incubated in the dark at 25°C for 3 to 10 days. N. oryzae was isolated at low frequencies from all plant tissues beginning at first bloom. Developing bolls at full bloom were colonized at a frequency of 48%. N. oryzae conidiophores were branched, flexuous, and pallid to brown with smooth walls 4 to 7 (5) µm thick. Conidiogenous cells were monoblastic, single, and 6 to 9 (7.5) µm in diameter. Conidia were single, smooth, broadly ellipsoidal, dark brown to black, single-celled, and 11 to 16 (14) µm in diameter (2). Principal component analysis was used to examine the relationship between disease incidence and weather parameters. Weather data was obtained from Auburn University Mesonet located in fields where the samples were collected. Principal components from weather data were ambient and soil maximum, minimum, and average temperature, maximum, minimum, and average relative humidity and precipitation. The first principal component, which is temperature, accounted for 61% of total joint variation among original observations. The second principal component, which was related to the moisture variables, accounted for 19% of the variation. The abundance of N. oryzae was correlated with the principal component factor moisture (r = -0.78**). The dry conditions experienced in this region were conducive to N. oryzae lint rot of cotton. This disease has been reported on cotton primarily in arid climates typical of the southwestern United States (1). To our knowledge, this is the first report of N. oryzae lint rot in the southeastern United States. References: (1) W. E. Batson. Boll rots. Pages 36-38 in: Compendium of Cotton Diseases. T. L. Kirkpatrick and C. S. Rothrock, eds. The American Phytopathological Society, St. Paul, MN. 2001. (2) M. B. Ellis. Dematiaceous Hyphomycetes, CAB, Kew, Surrey, England, 1971.

Interaction of Rotylenchulus reniformis with Seedling Disease Pathogens of Cotton.

The impact of 10 Fusarium species in concomitant association with Rotylenchulus reniformis on cotton seedling disease was examined under greenhouse conditions. In experiment 1, fungal treatments consisted of Fusarium chlamydosporum, F. equiseti, F. lateritium, F. moniliforme, F. oxysporum, F. oxysporum f.sp. vasinfectum, F. proliferatum, F. semitectum, F. solani, and F. sporotrichioides; Rhizoctonia solani; and Thielaviopsis basicola. The experimental design was a 2 x 14 factorial consisting of the presence or absence of R. reniformis and the 12 fungal treatments plus two controls in autoclaved field soil. In experiment 2, the same fungal and nematode treatments were examined in autoclaved or non-autoclaved soil. This experimental design was a 2 x 2 x 14 factorial consisting of field or autoclaved soil, presence or absence of R. reniformis, and the 12 fungal treatments plus two controls. In both tests, Fusarium oxysporum f. sp. vasinfectum, F. solani, R. solani, and T. basicola consistently displayed extensive root and hypocotyl necrosis that was more severe (P

Evaluation of methods to improve the diagnosis of systemic inflammation in alpacas.

BACKGROUND: The stoic nature of alpacas and limitations of current diagnostic tests make early recognition of inflammatory diseases in this species challenging. OBJECTIVES: In a model of mild systemic inflammation, this study evaluated the utility of different clinical and clinicopathologic variables as accurate predictors of inflammation in alpacas. ANIMALS: Twelve clinically healthy alpacas were randomly assigned to equal-sized treatment (TG) and control (CG) groups. After collection of initial blood samples (0 hour), lipopolysaccharide (LPS; 20 µg/kg/24 h) or saline was administered by SC osmotic mini-pumps (OMP) for 96 hours. Additional blood samples were collected at 12, 18, 24, 36, 48, 72, 96, 120, 144, and 240 hours and differential leukocyte counts and concentrations of globulin, albumin, iron, haptoglobin, and serum amyloid A were measured. RESULTS: Mild swelling was observed at OMP implantation sites in both groups. Other clinical signs of systemic inflammation were not observed. Total leukocytes, neutrophils, albumin, and globulin concentrations were not significantly different between groups. Compared with CG-alpacas, TG-alpacas had fewer lymphocytes (P = .0322), more band neutrophils (P = .0087), and higher neutrophil/lymphocyte ratios (P = .0295) during the first 96 hours of the study. During LPS administration, serum iron concentrations were significantly decreased in TG-alpacas (P < .0001). Haptoglobin concentrations of TG-animals exceeded those of CG-animals after removal of OMP (P = .0056). Serum amyloid A was not detectable in alpacas in this study. CONCLUSION AND CLINICAL IMPORTANCE: These results indicated that neutrophil/lymphocyte ratios and serum iron concentrations are early indicators of inflammation in alpacas. Additional research is needed to evaluate the acute phase protein responses of alpacas.

Distribution of bovine viral diarrhoea virus antigen in persistently infected white-tailed deer (Odocoileus virginianus).

Infection with bovine viral diarrhoea virus (BVDV), analogous to that occurring in cattle, is reported rarely in white-tailed deer (Odocoileus virginianus). This study evaluated the distribution of BVDV antigen in persistently infected (PI) white-tailed deer and compared the findings with those from PI cattle. Six PI fawns (four live-born and two stillborn) from does exposed experimentally to either BVDV-1 or BVDV-2 were evaluated. Distribution and intensity of antigen expression in tissues was evaluated by immunohistochemistry. Data were analyzed in binary fashion with a proportional odds model. Viral antigen was distributed widely and was present in all 11 organ systems. Hepatobiliary, integumentary and reproductive systems were respectively 11.8, 15.4 and 21.6 times more likely to have higher antigen scores than the musculoskeletal system. Pronounced labelling occurred in epithelial tissues, which were 1.9-3.0 times likelier than other tissues to contain BVDV antigen. Antigen was present in >90% of samples of liver and skin, suggesting that skin biopsy samples are appropriate for BVDV diagnosis. Moderate to severe lymphoid depletion was detected and may hamper reliable detection of BVDV in lymphoid organs. Muscle tissue contained little antigen, except for in the cardiovascular system. Antigen was present infrequently in connective tissues. In nervous tissues, antigen expression frequency was 0.3-0.67. In the central nervous system (CNS), antigen was present in neurons and non-neuronal cells, including microglia, emphasizing that the CNS is a primary target for fetal BVDV infection. BVDV antigen distribution in PI white-tailed deer is similar to that in PI cattle.

Tasco supplementation: effects on carcass characteristics, sensory attributes, and retail display shelf-life.

Two hundred crossbred cattle (Bos indicus x Bos taurus) were supplemented with 2% Tasco (Ascophyllum nodosum) in a commercial finishing facility to evaluate marbling score, USDA quality grade, sensory traits, and retail display shelf life. Treatment animals (n = 100) received a steam-rolled corn (Zea mays)-based diet containing 2% Tasco meal (DM basis), for 14 d beginning at d 45 of the finishing period and again 14 d before slaughter. Control animals (n = 100) received a steam-rolled corn (Zea mays)-based diet without Tasco at identical feeding periods. Carcasses from Tasco-fed cattle exhibited greater marbling scores (P = 0.003) than controls. There were no treatment effects (P > 0.05) on sensory, shear, or purge attributes of striploin or inside round steaks with the exception of inside round steaks from Tasco animals having a greater initial tenderness (P = 0.03) and lower off-flavor score (P = 0.002) than control steaks. The LM samples from Tasco-fed cattle had a greater percentage of ether extractable fat (P = 0.001) and lower percentage of protein (P = 0.001) than controls. Inside round samples from treated animals exhibited a greater percentage of moisture (P = 0.03) than control steaks. Visual lean color of striploin steaks was not affected by Tasco supplementation (P = 0.26); however, steaks from Tasco-treated animals were more uniform and had less discoloration and browning than those from controls (P = 0.005, 0.04, and 0.05, respectively). Inside round visual scores and instrument values reflected similar treatment responses (P < 0.05), with a majority of the effects on muscle redness (CIE a*, hue angle) and measures of discoloration. Tasco steaks were generally more red and less discolored during extended postmortem aging and retail exposure (P < 0.05). The results from this study indicate that short-term supplementation of 2% Tasco meal in feedlot cattle increases carcass quality and prolonged retail shelf life.

Epidemiological and experimental evidence for immunodeficiency affecting avian infectious bronchitis.

We evaluated the effects of viral immunodeficiency on the outcome of infectious bronchitis virus (IBV) infection in chickens as a hypothetical cause for failure of adequate protection in vaccinated chickens. Initially, we investigated IBV isolations from cases of respiratory disease in association with the presence of thymic and/or bursal atrophy in 322 submissions during 1997 to 2002. Arkansas (Ark)-type IBV was most frequently isolated in spite of extensive ArkDPI vaccination in the broiler industry. The number of IBV isolations was consistently higher in broilers aged 27 to 43 days, coinciding with lymphocytic depletion of the bursa and/or thymus, providing circumstantial evidence that immunodeficiency and IBV incidence may be linked. S1 gene sequence analyses, antigenic characterizations, and challenge of susceptible chickens demonstrated that the field IBV isolates tested were closely related to vaccine strains and had low pathogenicity for chickens. We experimentally evaluated the effects of immunodeficiency caused by co-infection with chicken anaemia virus and infectious bursal disease virus on the outcome of IBV infection. Clinical signs and histological lesions were more persistent in immunodeficient chickens. Local specific IgA production was delayed and lower levels were achieved in immunodeficient chickens. At the same time, IBV RNA concentrations in tracheas and lachrymal fluids were higher and more persistent in immunodeficient chickens. Collectively, these results indicate that viral immunodeficiency most probably plays a relevant role in the epidemiology and outcome of IBV infection.

The avian major histocompatibility complex influences bacterial skeletal disease in broiler breeder chickens.

This study evaluated bacterial skeletal disease in conjunction with the major histocompatibility complex (MHC) in a genetically pure line of broiler breeder chickens. Chickens from six broiler breeder flocks were examined for skeletal lesions, bacterial pathogens, and MHC genotype. During a 10-week period, eighty-eight, 9- to 21-week-old lame chickens and 34 normal, age-matched controls were selected. Tenosynovitis, arthritis, and femoral or tibiotarsal (or both) osteomyelitis occurred in 86 of 88 (97.7%) lame chickens. Ninety-five bacterial isolates were obtained from 83 of 88 (94.3%) lame birds and 4 of 34 (11.8%) controls. Staphylococcus spp. was isolated from 72.6% of the skeletal lesions, predominantly Staphylococcus aureus (38.9%). MHC B complex genotypes were determined by hemagglutination for 88 lame birds, 34 controls, and 200 randomly selected birds from each of the six flocks (1,200 total). Combined chi-square analysis revealed that the homozygous MHC genotypes B(A4/A4) (chi(2) = 14.54, P = 0.0063) and B(A12/A12) (chi(2) = 42.77, P = 0.0001) were overrepresented in the sample of symptomatic birds compared with random samples from the same flocks. The homozygous A4 and A12 MHC genotypes influenced flock chi-square values more than the corresponding heterozygotes. An MHC B complex influence on bacterial skeletal disease was apparent in this line of broiler breeders.

Measurement of energy expenditure in humans by doubly labeled water method.

The utility of the doubly labeled water method for the determination of energy expenditure and water output was investigated in humans. Approximately 10 g of 18O and 0.5 g of 2H as water was orally administered to four healthy adults. Total body water was determined from the isotope dilution, and the ensuing 18O and 2H disappearance rates from body water were determined for 13 days by mass spectrometric isotope ratio analysis of the urinary water. During this period, subjects were maintained on a measured diet to determine energy and water intake. The energy expenditure from the doubly labeled water method differed from dietary intake plus change in body composition by an average of 2%, with a coefficient of variation of 6%. The water outputs determined by the two methods differed by 1%, with a coefficient of variation of 7%. The doubly labeled water method is noninvasive, and the subjects could maintain their daily activities without restriction.

Short-chain fatty acids and succinate in feces of healthy human volunteers and their correlation with anaerobe cultural counts.

Short-chain fatty acids (SCFA) and succinate in fresh feces from 10 healthy human volunteers were detected with gas-liquid chromatography and were correlated with their fecal cultural counts. The SCFA content of feces did not change significantly after freezing, but the cultural counts of total anaerobes and bifidobacteria showed significant changes (0.001 less than P less than 0.01). A significant negative correlation (r = -0.78; 0.01 less than P less than 0.02) was found between the bifidobacteria cultural counts and the succinic acid concentration in fresh feces, which disappeared after freezing of the samples. Because of the significant differences in cultural counts and the shift in significant correlations after freezing, it is important to use fresh fecal samples for these correlation studies. Lactic acid and i-caproic acid were not found in the fecal samples. The results show that SCFA and organic acid concentrations cannot replace (an)aerobe cultural counts in fecal flora studies of healthy human volunteers because of the low rate of significant correlations between these two.

Variations in the anaerobic faecal flora of ten healthy human volunteers with special reference to the Bacteroides fragilis-group and Clostridium difficile.

Ninety nine stool specimens of ten healthy human volunteers were collected over a one year period, and processed anaerobically. The individual variations in intestinal colonization with bacteria of the Bacteroides fragilis-group were detected, using the Bacteroides Bile Esculin medium and an identification scheme for bile-resistant Bacteroides species. Clostridium difficile agar supplemented with cycloserine/cefoxtin was used to detect the incidence of C. difficile in this group. The species of the B. fragilis-group most often detected were: B. vulgatus (in 31 samples from ten persons), B. uniformis (22/9), B. fragilis (19/7). C. difficile was never detected in this group. The mean total anaerobic cultural counts (log) of the ten volunteers varied between 9.94 and 10.91. This shows that interindividual variations in anaerobic cultural counts of about one log are common. In spite of these moderate interindividual variations, intraindividual variations in time of up to three log were detected. The mean Bacteroides cultural counts showed a variation between 8.83 and 10.24. The mean DMCCs of the ten volunteers were between 10.22 and 10.73. We conclude that at least a three to four log difference from the control samples will be required to establish a significant change in anaerobic cultural count due to antibiotic treatment.

Short-chain fatty acid and organic acid concentrations in feces of 10 human volunteers and their correlation with anaerobe cultural over a 15-month period.

Short-chain fatty acid (SCFA) and organic acid concentrations were determined with gas-liquid chromatography (GLC) in fresh feces from 10 healthy volunteers, simultaneously with their fecal cultural counts. To find a simple and reliable method to detect disturbances in fecal flora, we calculated the intraindividual correlations between the concentrations determined by GLC and the fecal cultural counts. Twenty-three (4.7%) significant (P less than 0.05) linear correlations were thus found in nine of the volunteers. Using multivariate analysis, we attempted to assign fecal samples to individuals in accordance with their SCFA, cultural count, and organic acid profiles. Percentages of samples thus classified correctly were 49, 39, and 29, respectively. We conclude from this study that these percentages represent the normal situation in a group of healthy humans and that the low percentage of significant correlation coefficients shows that the relation between fecal SCFA/organic acid concentrations and fecal cultural counts has not been established.

Perinatal mortality in Bavaria, Germany, after the Chernobyl reactor accident.

As has been shown by the authors of a paper recently published in this journal, a deviation from a long-term trend in perinatal mortality within the former Federal Republic of Germany occurred in 1987, i.e. 1 year following the Chernobyl disaster. It is the aim of this study to make a comparison between the areas of the state Bavaria. Germany, with different fallout levels as well as between the observed and expected numbers of perinatal deaths relating to these areas. The expected numbers of perinatal deaths, defined as external standard, were derived from the remainder of the former FRG. Testing an a priori formulated hypothesis revealed no differences in the temporal development of perinatal mortality between the areas with different fallout levels and subsequent exposure. Including May 1986 into the analysis revealed a significant increase during the first 3 months after the accident, which is due to an excess in May alone. Since no elevated radiation risks for the last days in utero are known, the additional Chernobyl radiation exposure is not plausible as a causative agent. Further analyses on stillbirths showed an increase in Southern Bavaria during the first 2 years following the accident. Later on, the rates were comparable to the expected values again.

The effect of FCE 22891, a new oral penem, on faecal flora anaerobes and their fermentation end products in patients with chronic obstructive pulmonary disease.

The influence of FCE 22891 on the faecal flora was investigated in 11 patients with an acute exacerbation of chronic obstructive pulmonary disease (COPD). Colony counts of faecal (an)aerobes and concentrations of their short-chain fatty acids and organic acids were determined simultaneously in fresh faeces before, during and after administration of the drug, and compared to those of healthy human volunteers. The MIC of FCE 22891 for the 142 isolated anaerobes was determined, and compared to the biologically active concentration of the drug in faeces. The Bacteroides colony counts of the patients increased significantly by day 9 compared to day 3, but were significantly lower than those of the healthy controls before, during and after the study. Significant changes in short-chain fatty acids and organic acid concentrations occurred in faeces of the patients during and after treatment, and especially when compared to healthy controls. A strong increase in MICs during treatment was found in Clostridium species, other than Clostridium difficile. FCE 22891 had only a moderate effect on the composition of the anaerobic faecal flora, but bacterial fermentation was mainly disturbed before and early on in treatment, which could have been caused by the disease.