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Biomedical subjects

M Katouli

Publications and source records attributed to M Katouli.

At least 19 recordsLinked to original sources
PubMed2006

Comparison of the efficacy of an existing versus a locally developed metabolic fingerprint database to identify non-point sources of faecal contamination in a coastal lake.

A comparison of the efficacy of an existing large metabolic fingerprint database of enterococci and Escherichia coli with a locally developed database was undertaken to identify the sources of faecal contamination in a coastal lake, in southeast Qld., Australia. The local database comprised of 776 enterococci and 780 E. coli isolates from six host groups. In all, 189 enterococci and 245 E. coli biochemical phenotypes (BPTs) were found, of which 118 and 137 BPTs were unique (UQ) to host groups. The existing database comprised of 295 enterococci UQ-BPTs and 273 E. coli UQ-BPTs from 10 host groups. The representativeness and the stability of the existing database were assessed by comparing with isolates that were external to the database. In all, 197 enterococci BPTs and 179 E. coli BPTs were found in water samples. The existing database was able to identify 62.4% of enterococci BPTs and 64.8% of E. coli BPTs as human and animal sources. The results indicated that a representative database developed from a catchment can be used to predict the sources of faecal contamination in another catchment with similar landuse features within the same geographical area. However, the representativeness and the stability of the database should be evaluated prior to its application in such investigation.

Animals↗
PubMed2006

Tidal and longitudinal variation of faecal indicator bacteria in an estuarine creek in south-east Queensland, Australia.

A two-part study conducted in Elimbah Creek, a shallow estuarine waterway in south-east Queensland, Australia, examined the variations in physico-chemical parameters of water quality, chlorophyll a, and faecal indicator bacteria abundances of total coliform, Escherichia coli and enterococci, spatially at high and low tide and also over a 12h tidal cycle. Gradients of increasing faecal indicator bacteria from the mouth to the upper, tidal freshwater reaches were observed, despite isolated peaks during either tidal phase. Phytoplankton biomass (measured as chlorophyll a) did not noticeably increase during the study. Variations in the abundances of all three faecal indicator bacteria and their correlations with physico-chemical parameters indicated that although the creek was likely subject to some level of faecal contamination, tidal movement serves to limit faecal indicator and phytoplankton levels in the creek through physico-chemical stress and dilution. However, each faecal indicator bacteria investigated provided different estimations of faecal contamination, which challenges the effectiveness of employing a single type of faecal indicator bacteria when investigating the level of faecal contamination in waterways.

Biomass↗
PubMed2006

Prevalence of environmental Aeromonas in South East Queensland, Australia: a study of their interactions with human monolayer Caco-2 cells.

AIMS: To investigate the prevalence of Aeromonas in a major waterway in South East Queensland, Australia, and their interactions with a gut epithelial model using Caco-2 cells. METHODS AND RESULTS: A total of 81 Aeromonas isolates, collected from a major waterway in South East Queensland, Australia, were typed using a metabolic fingerprinting method, and tested for their adhesion to HEp-2 and Caco-2 cells and for cytotoxin production on Vero cells and Caco-2 cells. Aeromonas hydrophila had the highest (43%) and Aeromonas veronii biovar sobria had the lowest (25%) prevalence. Four patterns of adhesion were observed on both HEp-2 and Caco-2 cell lines. Representative isolates having different phenopathotypes (nine strains) together with two clinical isolates were tested for their translocation ability and for the presence of virulence genes associated with pathogenic Escherichia coli. The rate and degree of translocation across Caco-2 monolayers varied among strains and was more pronounced with LogA pattern. Translocation was associated with the adherence of strains to Caco-2 cells microvilli, followed by internalization into Caco-2 cells. Two Aer. veronii biovar sobria strains were positive for the presence of heat-labile toxin genes, with one strain also positive for Shiga-like toxin gene. CONCLUSIONS: Pathogenic strains of Aeromonas carrying one or more virulence characteristics are highly prevalent in the waterways studied and are capable of translocating across a human enterocyte cell model. SIGNIFICANCE AND IMPACT OF THE STUDY: This study indicates that Aeromonas strains carrying one or more virulence properties are prevalent in local waterways and are capable of translocating in a human enterocyte cell culture model. However, their importance in human gastrointestinal disease has yet to be verified under competitive conditions of the gut.

Aeromonas↗
PubMed2006

Evaluation of the methods for enumerating coliform bacteria from water samples using precise reference standards.

AIMS: To use BioBall cultures as a precise reference standard to evaluate methods for enumeration of Escherichia coli and other coliform bacteria in water samples. METHODS AND RESULTS: Eight methods were evaluated including membrane filtration, standard plate count (pour and spread plate methods), defined substrate technology methods (Colilert and Colisure), the most probable number method and the Petrifilm disposable plate method. Escherichia coli and Enterobacter aerogenes BioBall cultures containing 30 organisms each were used. All tests were performed using 10 replicates. The mean recovery of both bacteria varied with the different methods employed. CONCLUSIONS: The best and most consistent results were obtained with Petrifilm and the pour plate method. Other methods either yielded a low recovery or showed significantly high variability between replicates. SIGNIFICANCE AND IMPACT OF THE STUDY: The BioBall is a very suitable quality control tool for evaluating the efficiency of methods for bacterial enumeration in water samples.

Colony Count, Microbial↗
PubMed2006

Evaluation of an alternative method for the enumeration and confirmation of Clostridium perfringens from treated and untreated sewages.

AIMS: Clostridium perfringens is recommended as a suitable indicator bacterium for human enteric viruses, Giardia cysts and Cryptosporidium oocysts in finished water and in the assessment and evaluation of water treatment. Several agars and confirmation procedures were evaluated in parallel with the Australian/New Zealand Standard (AS/NZ) Method for the enumeration of Cl. perfringens from treated and untreated sewage samples. METHODS AND RESULTS: The current AS/NZ method utilizes tryptose sulfite cycloserine agar (TSC), lactose gelatin medium (LG) and nitrate motility medium (NM) at an incubation temperature of 37 degrees C. Sixty treated and untreated sewage samples were used to evaluate TSC agar, membrane Cl. perfringens agar (mCP), Perfringens agar (OPSP) and Perfringens agar with 4-methylumbelliferyl phosphate (OPSP-MUP) for enumeration of Clostridium. An incubation temperature of 44 degrees C for 24 h was used for comparison. Confirmation procedures were also evaluated using 103 isolates and included LG and NM, ortho-nitrophenyl-beta-D-galactopyranoside (ONPG) with MUP (ONPG-MUP) and phosphatase reagent (PR). OPSP compared favourably with TSC agar. One false negative result was obtained from each of the LG/NM and ONPG-MUP procedures. No false results were obtained using the PR confirmation procedure. CONCLUSIONS: OPSP agar and PR were determined as suitable replacements for the AS/NZ Standard procedure with no interference from spreading organisms. SIGNIFICANCE AND IMPACT OF THE STUDY: This is a simple and rapid method for isolating and enumerating Cl. perfringens from sewage samples and confirmed results can be reported more quickly due to shorter analytical turnaround times.

Clostridium perfringens↗
PubMed2006

Population similarity of enterococci and Escherichia coil in surface waters: A predictive tool to trace the sources of fecal contamination.

A biochemical fingerprinting method (the PhPlate system) was used to compare similarities between Escherichia coli and enterococci populations from surface water samples with those found in different animal species during the wet and the dry seasons in order to predict the dominant source(s) of fecal contamination in a local creek. A significant increase in the number and diversity of enterococci was observed in the creek during the wet season. Enterococci population from water samples also showed a higher population similarity with animal species than did E. coli. A higher population similarity was found between both indicator bacteria and animal species during the wet season with highest population similarities found in dogs, horses, cows and kangaroos. In contrast, a low population similarity was found for both fecal indicator bacteria from humans with water samples during the wet and the dry seasons, indicating that humans are not a major source of contamination in the studied creek. The results also indicate that the population similarity analysis of enterococci population has an advantage over E. coli in tracing the possible source(s) of contamination in the studied creek and that population similarity analysis as used in this study can be used to predict the source(s) of fecal contamination in surface waters.

Animals↗
PubMed2005

Virulence characteristics of Escherichia coli strains causing acute cystitis in young adults in Iran.

BACKGROUND: Escherichia coli strains that cause cystitis posses virulence properties that facilitate their colonisation and persistence in the bladder. In Iran, despite the high number of the urinary tract infections, very few studies has been done to determine the role of these virulence properties in the pathogenesis of E. coli cyctitis. PATIENTS AND METHODS: Eighty-seven strains of E. coli, isolated from young adults with cystitis in Shiraz, Iran, were examined for the expression of type 1 and P-fimbriae, mannose resistant haemagglutination, haemolysin production, aerobactin-mediated iron uptake, O:K serotypes, biochemical phenotypes (BPTs) and their antibiotic susceptibility patterns. RESULTS: Seventy-six percent of the strains expressed multiple virulence properties. There was a significant correlation between the presence of aerobactin and the expression of type 1 fimbriae. All P-fimbriated strains produced aerobactin with 50% of them also coexpressing haemolysin. Of the 29 different O:K serotypes identified, 42% belonged to serotypes not commonly found among European serotypes associated with UTI. Strains of O groups 4 and 6 expressed more virulence factors than the others. A high resistance against ampicillin, trimethoprim and cotrimoxasol was observed among the isolates with 53% of the isolates showing multiresistance to these three antibiotics. Certain BPTs were also found among O:K serotypes with some containing strains of the same virulence profile. CONCLUSION: We conclude that certain colonal groups of E. coli are commonly associated with cystitis in young adults in Iran with strains possessing a combination of aerobactin and type 1 fimbriae being the dominant ones and belonging to serotypes not commonly found in Europe. We also conclude that the multiple antibiotic resistant E. coli strains causing cyctitis are highly prevalent in this part of the country.

Acute Disease↗
PubMed2005

Evidence of septic system failure determined by a bacterial biochemical fingerprinting method.

AIMS: To provide evidence of septic system failure by comparing two faecal indicator bacteria, enterococci and Escherichia coli, from defective septic tanks and adjacent creeks. METHODS AND RESULTS: A biochemical fingerprinting method was used to type and compare enterococci and E. coli strains from 39 septic tanks with creek water samples. Phenotypic diversity of enterococci (0.5 +/- 0.3) and E. coli (0.5 +/- 0.3) in septic tanks were significantly lower than those found in water samples (0.8 +/- 0.1, P < 0.0001 for enterococci and 0.9 +/- 0.1, P < 0.0001 for E. coli). Among 1072 enterococci isolates tested from septic tanks, 203 biochemical phenotypes (BPTs) were found of which 98 BPTs from 33 septic tanks were identical to several water samples. Similarly, among 621 E. coli isolates tested from septic tanks, 159 BPTs were found of which 53 BPTs from 26 septic tanks were also identical to water samples. The number of the latter bacteria was significantly (P = 0.01) higher in water samples collected from downstream compared with that of upstream in the study area. A high similarity between the populations of both indicator bacteria was also found between defective septic tanks and downstream water samples further indicating the contamination of both creeks by defective septic systems. CONCLUSIONS: Biochemical fingerprinting of faecal indicator bacteria is a useful and rapid method to provide direct evidence for septic system failure. Combination of both faecal indicator bacteria (enterococci and E. coli) provides a better judgement of the performance of a septic system. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is the first to provide direct evidence of septic system failure by identifying the presence of specific bacterial types in septic tanks and surface waters. Based on our findings, we suggest that the performance evaluation of a septic system should be accompanied by direct analysis of faecal indicator bacteria.

Animals↗
PubMed2005

Host species-specific metabolic fingerprint database for enterococci and Escherichia coli and its application to identify sources of fecal contamination in surface waters.

A metabolic fingerprint database of enterococci and Escherichia coli from 10 host groups of animals was developed to trace the sources of fecal contamination in surface waters. In all, 526 biochemical phenotypes (BPTs) of enterococci and 530 E. coli BPTs were obtained from 4,057 enterococci and 3,728 E. coli isolates tested. Of these, 231 Enterococcus BPTs and 257 E. coli BPTs were found in multiple host groups. The remaining 295 Enterococcus BPTs and 273 E. coli BPTs were unique to individual host groups. The database was used to trace the sources of fecal contamination in a local creek. The mean diversities (Di) of enterococci (Di = 0.76 +/- 0.05) and E. coli (Di = 0.88 +/- 0.04) were high (maximum 1) in water samples, indicating diverse sources of fecal contamination. Overall, 71% of BPTs of enterococci and 67% of E. coli BPTs from water samples were identified as human and animal sources. Altogether, 248 Enterococcus BPTs and 282 E. coli BPTs were found in water samples. Among enterococci, 26 (10%) BPTs were identical to those of humans and 152 BPTs (61%) were identical to those of animals (animal BPTs). Among E. coli isolates, 36 (13%) BPTs were identical to those of humans and 151 (54%) BPTs were identical to those of animals. Of the animal BPTs, 101 (66%) Enterococcus BPTs and 93 (62%) E. coli BPTs were also unique to individual animal groups. On the basis of these unique Enterococcus BPTs, chickens contributed 14% of contamination, followed by humans (10%), dogs (7%), and horses (6%). For E. coli, humans contributed 13% of contamination, followed by ducks (9%), cattle (7%), and chickens (6%). The developed metabolic fingerprint database was able to distinguish between human and animal sources as well as among animal species in the studied catchment.

Animals↗
PubMed2004

Development of post-weaning diarrhoea in piglets. Relation to presence of Escherichia coli strains and rotavirus.

Weaning of piglets complicated with an exposure to pathogenic strains of Escherichia coli was scrutinized in two sets. The first set comprised 20 animals representing two litters and the second set included 30 animals from five litters. The piglets were either left as controls or exposed to one or three pathogenic strains of E. coli. Aiming to simulate a natural exposure the challenge strains were spread on the floor of the pens at weaning. In addition the pigs experienced several non-infectious stress factors commonly occurring at that occasion. Some groups were given adrenocorticotropic hormone (ACTH), aiming to simulate a stressful weaning. The balance and the composition of the faecal coliform populations, measured by a metabolic fingerprinting method, was disturbed among all animals following weaning. This disturbance was more pronounced and lasted longer among piglets exposed to pathogenic strains of E. coli. All piglets exposed to pathogenic E. coli shed these strains in faeces. Diarrhoea was induced in the groups exposed to E. coli, but not among the control animals. Pigs not treated with ACTH and subjected to a single pathogenic strain of E. coli became infected but did not develop diarrhoea unless if coinciding with shed of rotavirus. Control pigs excreting rotavirus had no diarrhoea. Diarrhoea was most frequent in the groups exposed to three pathogenic strains of E. coli, and in these groups diarrhoea was seen in the absence of rotavirus. ACTH administration amplified the clinical signs. The litter of origin influenced the development of post-weaning diarrhoea.

Animal Husbandry↗
PubMed2004

Evaluation of five membrane filtration methods for recovery of Cryptosporidium and Giardia isolates from water samples.

We evaluated the efficiency of five membrane filters for recovery of Cryptosporidium parvum oocysts and Giardia lamblia cysts. These filters included the Pall Life Sciences Envirochek (EC) standard filtration and Envirochek high-volume (EC-HV) membrane filters, the Millipore flatbed membrane filter, the Sartorius flatbed membrane filter (SMF), and the Filta-Max (FM) depth filter. Distilled and surface water samples were spiked with 10 oocysts and 10 cysts/liter. We also evaluated the recovery efficiency of the EC and EC-HV filters after a 5-s backwash postfiltration. The backwashing was not applied to the other filtration methods because of the design of the filters. Oocysts and cysts were visualized by using a fluorescent monoclonal antibody staining technique. For distilled water, the highest percent recovery for both the oocysts and cysts was obtained with the FM depth filter. However, when a 5-s backwash was applied, the EC-HV membrane filter (EC-HV-R) was superior to other filters for recovery of both oocysts (n = 53 +/- 15.4 per 10 liters) and cysts (n = 59 +/- 11.5 per 10 liters). This was followed by results of the FM depth filter (oocysts, 28.2 +/- 8, P = 0.015; cysts, 49.8 +/- 12.2, P = 0.4260), and SMF (oocysts, 16.2 +/- 2.8, P = 0.0079; cysts, 35.2 +/- 3, P = 0.0079). Similar results were obtained with surface water samples. Giardia cysts were recovered at higher rates than were Cryptosporidium oocysts with all five filters, regardless of backwashing. Although the time differences for completion of filtration process were not significantly different among the procedures, the EC-HV filtration with 5-s backwash was less labor demanding.

Animals↗
PubMed2004

Studies on calf diarrhoea in Mozambique: prevalence of bacterial pathogens.

The prevalence of diarrhoea in calves was investigated in 8 dairy farms in Mozambique at 4 occasions during 2 consecutive years. A total of 1241 calves up to 6 months of age were reared in the farms, and 63 (5%) of them had signs of diarrhoea. Two farms had an overall higher prevalence (13% and 21%) of diarrhoea. Faecal samples were collected from all diarrhoeal calves (n = 63) and from 330 healthy calves and analysed for Salmonella species, Campylobacter jejuni and enterotoxigenic Escherichia coli (ETEC). Salmonella spp. was isolated in only 2% of all calves. Campylobacter was isolated in 11% of all calves, irrespective of health condition, and was more frequent (25%) in one of the 2 diarrhoeal farms (p = 0.001). 80% of the isolates were identified as C. jejuni. No ETEC strains were detected among the 55 tested strains from diarrhoeal calves, but 22/55 (40%) strains from diarrhoeal calves and 14/88 (16%) strains from healthy calves carried the K99 adhesin (p = 0.001). 6,757 E. coli isolates were typed with a biochemical fingerprinting method (the PhenePlate) giving the same E. coli diversity in healthy and diarrhoeal calves. Thus it was concluded: i) the overall prevalence of diarrhoea was low, but 2 farms had a higher prevalence that could be due to an outbreak situation, ii) Salmonella did not seem to be associated with diarrhoea, iii) Campylobacter jejuni was common at one of the 2 diarrhoeal farms and iv) ETEC strains were not found, but K99 antigen was more prevalent in E. coli strains from diarrhoeal calves than from healthy, as well as more prevalent in one diarrhoeal farm.

Animals↗
PubMed2000

Weaning of piglets. Effects of an exposure to a pathogenic strain of Escherichia coli.

The influence of weaning on day 32 and a simultaneous challenge with a pathogenic strain of Escherichia coli was studied in eight piglets. Another nine weaned but non-infected piglets were used as controls. The distribution of peripheral blood mononuclear cells (PBMC) into subpopulations, as well as their response when stimulated in vitro by pokeweed mitogen, changed in a similar manner during post-weaning in both groups. In contrast, superior responses were recorded for PBMC collected from the challenged pigs when stimulated in vitro with concanavalin A and with a heat-inactivated extract of the E. coli strain used for infection, respectively. Despite a successful colonization of the challenge strain, no clinical signs of disease were recorded. Nor did the daily weight gain or the number of E. coli, enterococci, or Clostridium perfringens excreted per gram of faeces differ between the groups. However, the weaning induced a marked decrease in the diversity of coliforms in individual piglets, which announced a reduced colonization resistance of that flora. Also, a decreased homogeneity between coliform floras of different piglets was observed following weaning. The decreased homogeneity indicated that different strains of E. coli were predominant in different animals, which may in turn facilitate the spread of pathogenic strains. The enteric changes were more pronounced and lasted longer in infected animals. Still, the influence of a sole pathogenic strain of E. coli was not enough to induce post-weaning diarrhoea.

Animals↗
PubMed2000

Bacterial translocation in experimental shock is dependent on the strains in the intestinal flora.

BACKGROUND: Enteric microorganisms are responsible for a significant proportion of post-surgical infections. Intestinal mucosal injury may permit translocation of bacteria and endotoxin. This study investigates translocation in peritonitis and ischemia/reperfusion by inoculating different bacterial species into the small intestine. METHODS: Twenty-five pigs were monitored hemodynamically and divided into three groups: controls (C), ischemia/reperfusion (I/R), and peritonitis (P). Intramucosal pH (pHi) was calculated tonometrically. A perfusion tube was positioned in the ileum for inoculation of the bacterial strains. In a first study period a non-pathogenic bacterium was used, whereas Escherichia coli strains with known ability to translocate were used in a second. Blood and mesenteric lymph nodes (MLNs) were obtained for bacterial culture and endotoxin analyses. RESULTS: Mesenteric arterial blood flow and pHi decreased in groups I/R and P. Endotoxin levels increased in these groups in period 1, whereas in period 2 an increase over time was only observed in group P. No bacterial translocation to blood or MLNs occurred in period 1. In period 2 bacteria translocated to MLNs in all animals, including controls. Translocation to central and/or mesenteric venous blood was found in all groups, but mainly in I/R and P. The incidence of mucosal injury was similar in the two periods. CONCLUSIONS: Since positive blood and MLN samples were only found in period 2, we conclude that translocation of bacteria seems to be more dependent on the presence of translocating strains in the intestinal bacterial flora than on the mucosal insult.

Analysis of Variance↗
PubMed2000

Local short-chain fatty acids supplementation without beneficial effect on inflammation in excluded rectum.

BACKGROUND: Rectal instillation of short-chain fatty acids (SCFA), important nutrients for the colorectal mucosa, has been suggested to be of therapeutic value in distal intestinal inflammation. METHODS: In this study nine patients with Hartmann-closed rectum after colectomy for acute colitis were investigated. In a double-blind crossover trial an enema containing SCFA or a placebo solution was administered twice daily for 3 weeks. Before entry into the protocol, after each treatment period, and 6 weeks after the study period the patients' symptoms were evaluated, rectal endoscopy was performed, histologic samples were scored, and microbiologic analyses were carried out. RESULTS: No significant differences in symptoms, in mucosal inflammation, in histologic scoring, or in microbiologic studies were found between SCFA and placebo periods. Unexpectedly, all but one patient entirely lacked coliform bacteria in the rectum. CONCLUSIONS: In this study SCFA enemas had no beneficial effect on inflammation in excluded rectum in patients earlier submitted to colectomy for colitis. However, a different rectal flora was detected in these patients.

Adult↗
PubMed2000

Clonal groups of enteropathogenic Escherichia coli isolated in case-control studies of diarrhoea in Bangladesh.

Recent case-control studies in Bangladesh showed a high prevalence of enteropathogenic Escherichia coli (EPEC) strains (identified by DNA probes for virulence genes) associated with childhood diarrhoea. However, the clonal status of these strains is not known. A total of 94 EPEC isolates from 80 children with diarrhoea and 14 healthy matched controls isolated during 1991-1992 and 1993-1994 was characterised by serogrouping, enterobacterial repetitive intergenic consensus sequence PCR, and by a biochemical fingerprinting method (the phene plate or PhP system). Twelve O serogroups were found with O114 (n = 19) and O127 (n = 23) being the dominant serogroups. Most strains of O114 belonged to the same PhP/PCR types. Strains of O127 contained 16 that produced cytolethal distending toxin (CDT) and seven that did not; both were found among patients as well as controls. Results of PCR and PhP typing showed that CDT-positive strains belonged to the same clonal group and were related to one of the two PhP/PCR types of CDT-negative O127 strains. Thirty-one EPEC strains were O non-typable and 21 strains belonged to other less prevalent serogroups. These strains belonged to diverse PhP/PCR types and did not show any similarity to the strains of two major serogroups, O114 and O127. The results suggest that two clonal groups of EPEC strains are predominantly associated with childhood diarrhoea in Bangladesh.

Bacterial Typing Techniques↗
PubMed1999

The effect of zinc oxide supplementation on the stability of the intestinal flora with special reference to composition of coliforms in weaned pigs.

The effect of a dietary supplementation of zinc oxide (ZnO) on the stability of the intestinal flora and on the composition of coliforms in weaned pigs was investigated. Faecal floras were characterized by their metabolic activities and fermentative capacity (FC) using the Phene Plate generalized microplate. Coliforms were characterized by conventional enumeration and by the Phene Plate-RS plates. The latter measured FC, phenotypic diversity, persistence of each coliform strain in piglets, and similarity among the coliform populations within groups. From weaning onwards, the control pigs (n = 5) were fed a basal diet ad libitum, while experimental pigs (n = 5) were given the same food supplemented with 2500 ppm ZnO. Metabolic fingerprinting of faecal floras indicated marked differences between the composition of floras of treated and control pigs during the first 2 weeks post-weaning. The FC of faecal flora in both groups decreased as pigs aged, but it was significantly (P </= 0.0001) lower in control pigs during the first 2 weeks post-weaning. Neither the number of coliforms, nor their FC-values, differed between the groups. However, during the first 2 weeks post-weaning, there was a significant increase in both variety (P = 0.019) and diversity (P </= 0.001) of coliforms in control pigs compared with the ZnO treated group. Homogeneity between coliform populations of piglets was high during the suckling period, indicating the presence of many identical strains among piglets. This, however, decreased in control pigs during the first 2 weeks post-weaning. Several coliform strains that colonized the gut at the early stage of the pigs' life were found to be resident in animals of both groups. It is concluded that supplementation of ZnO to weaned pigs helped to maintain the stability of the intestinal microflora and the diversity of coliforms during the first 2 weeks post-weaning, but not later, and that ZnO supplementation to creep feed should be restricted to the first 2 weeks post-weaning in veterinary practice.

Animals↗