Ml Of Feces Research Articles

Evaluation of a peroxygen-based disinfectant for inactivation of porcine epidemic diarrhea virus at low temperatures on metal surfaces

Porcine epidemic diarrhea virus (PEDV) spread rapidly across the United States in part due to contaminated livestock trailers. The objective of this study was to test a peroxygen-based disinfectant for the ability to inactivate PEDV on aluminum surfaces at 4 °C or −10 °C. Forty 3-week-old individually housed barrows were used as a bioassay to determine the infectivity of PEDV after treatment with either a 1:100 or 1:600 dilution of a peroxygen-based disinfectant with 10 or 30 min of contact time. One coupon matched to one pig was the experimental unit. Coupons in the positive control and disinfectant treatment groups were contaminated with 2 mL of feces spiked with PEDV. A negative control group was contaminated with PEDV-negative feces. Following treatment, the feces and disinfectant remaining in the coupons was collected and administered to pigs intragastrically. Rectal swabs were collected from pigs 3 and 7 days post-inoculation (DPI) and tested for PEDV by RT-qPCR. Samples from all coupons, except the negative control, were positive by RT-qPCR for PEDV before and after treatment. All rectal swabs from the pigs in the negative control and the seven disinfectant treatment groups were RT-qPCR negative for PEDV on 3 and 7 DPI. All pigs in the positive control at 4 °C and 3 of 4 pigs in the positive control conducted at −10 °C were RT-qPCR positive for PEDV on 3 and 7 DPI. Both the 1:100 and 1:600 dilutions of peroxygen-based disinfectant successfully inactivated PEDV under the conditions of this study.

Human pathogenic microsporidia detection in agricultural samples: method development and assessment

A detection method was developed and assessed for the sensitive recovery of microsporidia from livestock fecal and manure-impacted environmental samples. Sensitive recovery of microsporidia was achieved when samples were subjected to 1) purification by sucrose floatation, 2) DNA extraction using the Qiagen QIAamp DNA Stool Mini Kit, 3) polymerase chain reaction (PCR) analysis using generic primers for microsporidia, and 4) DNA sequence analysis to identify which microsporidia were present in each sample. Livestock fecal and wastewater samples were inoculated with 1,000 and 100 Encephalitozoon intestinalis spores/g or ml of feces or wastewater. For cattle wastewater, ten of ten replicates were positive by PCR at concentrations of 1,000 spores/ml, and two of ten replicates were positive at concentrations of 100 spores/ml. For swine wastewater, ten of ten replicates were positive at concentrations of 1,000 spores/ml, and four of ten replicates were positive at concentrations of 100 spores/ml. For cattle feces, three of ten replicates were positive at the concentration of 1,000 spores/g. Several environmental samples were screened using this method, with two of 34 samples positive for human pathogenic microsporidia. To our knowledge, this is the first report of Encephalitozoon cuniculi detection in swine feces and wastewater.

Detection of Cryptosporidium parvum oocysts in bovine feces by monoclonal antibody capture enzyme-linked immunosorbent assay

A monoclonal antibody enzyme-linked immunosorbent assay (ELISA) was developed to detect Cryptosporidium parvum oocysts in bovine feces. Fecal oocysts were concentrated by centrifugation through Formalin-ethyl acetate solution and captured with monoclonal antibody 18.280.2 reactive with C. parvum oocysts. Captured oocysts were detected with goat anti-oocyst serum, following the addition of a peroxidase conjugate of rabbit anti-goat immunoglobulin and O-phenylenediamine substrate. The assay was specific for Cryptosporidium sp. oocysts and did not detect oocysts of Eimeria auburnensis, Eimeria bovis, Eimeria ellipsoidalis, or Eimeria zuernii. Assay sensitivity allowed detection of 3 x 10(5) oocysts per ml of feces, compared with 1 x 10(6) oocysts per ml detected by examination of acid-fast-stained fecal smears and 1 x 10(3) oocysts per ml detected by indirect immunofluorescence. The capture ELISA was suitable for diagnostic analysis of bovine fecal samples and for assessment of oocyst shedding in experimentally infected calves. This assay may also prove useful for diagnostic assessment of humans in which cryptosporidiosis is suspected.

Enumeration and isolation of cellulolytic and hemicellulolytic bacteria from human feces.

The fibrolytic microbiota of the human large intestine was examined to determine the numbers and types of cellulolytic and hemicellulolytic bacteria present. Fecal samples from each of five individuals contained bacteria capable of degrading the hydrated cellulose in spinach and in wheat straw pretreated with alkaline hydrogen peroxide (AHP-WS), whereas degradation of the relatively crystalline cellulose in Whatman no. 1 filter paper (PMC) was detected for only one of the five samples. The mean concentration of cellulolytic bacteria, estimated with AHP-WS as a substrate, was 1.2 X 10(8)/ml of feces. Pure cultures of bacteria isolated on AHP-WS were able to degrade PMC, indicating that interactions with other microbes were primarily responsible for previous low success rates in detecting fecal cellulolytic bacteria with PMC as a substrate. The cellulolytic bacteria included Ruminococcus spp., Clostridium sp., and two unidentified strains. The mean concentration of hemicellulolytic bacteria, estimated with larchwood xylan as a substrate, was 1.8 X 10(10)/ml of feces. The hemicellulose-degrading bacteria included Butyrivibrio sp., Clostridium sp., Bacteroides sp., and two unidentified strains, as well as four of the five cellulolytic strains. This work demonstrates that many humans harbor intestinal cellulolytic bacteria and that a hydrated cellulose source such as AHP-WS is necessary for their consistent detection and isolation.

Persistent High Numbers ofClostridium perfringensin the Intestines of Japanese Aged Adults

TSN agar was applicable for enumeration of Clostridium perfringens in fecal samples of adults but not in those of infants. It was demonstrated using TSN agar that some healthy aged adults had persistently carried C. perfringens at levels ranging from 10(7) to 10(9), while some others ranged from 10(3) to 10(6) per ml volume of fecal sample although all of these adults had the same diets. In the test for agglutinability of isolates of C. perfringens collected from two elderly adults, a younger adult and a baby, it was demonstated that most of the isolates obtained from an aged adult of high levels for 19 months belonged the same serotype, while rapid alteration of serotypes could be observed in three other persons with high or low levels. In spite of as many as 10(9) C. perfringens per ml of feces, no trace of a-toxin could be detected in the fecal samples. In in vitro tests, fecal suspension suppressed the production of a-toxin although it allowed the organism to grow sufficiently.

A new convenient, rapid and accurate method for determination of total lipids in feces

1. 1. A new, simple and rapid colorimetric micromethod for determination of total lipids in the petroleum ether extract of feces is proposed. The method, based on the sulfophosphovanillin reaction, was found to be of satisfactory precision and accuracy. 2. 2. The concentration of total lipids determined in meconium of 40 healthy newborns in the first five days of life, was 1 to 15 g/100 ml of feces.

Comparative Observations on Experimental Schistosoma mansoni Infections in African Green and Rhesus Monkeys

The pattern of egg excretion and the number of schistosomes are compared in five African green (Cercopithecus aethiops pygerythrus and C. aethiops sabaeus) and five rhesus monkeys. Egg excretion in the green monkey was lower during the acute phase and declined more slowly thereafter. The green monkeys maintained a significantly higher number of worms over a period of many months. The number of eggs passed by green monkeys during chronic infections was much less than would be expected from the number of live worms recovered at autopsy. Although primate hosts are valuable in schistosomiasis research, rhesus monkeys, which have been used mostly, rapidly develop strong immunity to schistosomes which reduces the worm burden and egg excretion (Meleney and Moore, 1954; Vogel, 1958; Naimark et al., 1960; Meisenhelder, Olszewski, and Thompson, 1960; Sadun et al., 1961; Thompson, Meisenhelder, and Najarian, 1962). Although improvisations permit the evaluation of drugs against Schistosoma mansoni infection in the rhesus monkey (Thompson et al., 1962), acquired immunity limits its value for this and many other purposes. The importance of searching for a primate host better than the rhesus monkey has been emphasized in a report to the World Health Organization (1959). Vogel (1958) stated, without elaboration, that the survival of S. mansoni and the duration of its egg excretion is much longer in African green monkeys than in the rhesus. These considerations stimulated the present observations dealing with the course of S. mansoni infection in African green monkeys relative to rhesus monkeys. MATERIALS AND METHODS The animals infected during this work included three Cercopithecus aethiops pygerythrus (the East African green monkey) and two C. aethiops sabaeus (the West African green monkey). Four of these were studied in parallel as pairs with a monkey of each subspecies in each pair, i.e., numbers 25 and 138, 38 and 39. Received for publication 9 January 1963. As detailed accounts appear elsewhere (Najarian and Thompson, 1958; Thompson et al., 1962), the materials and techniques will be described only briefly. The monkeys were anesthetized intravenously with sodium thiamylal (Surital ?, Parke, Davis and Co.) and exposed percutaneously for 45 min to S. mansoni cercariae (Puerto Rican strain) collected from 30 or more Australorbis glabratus. The course of infection was followed by semiquantitative stool examinations for eggs; acidether preparations of 1 ml of feces were examined twice weekly from the 5th week after exposure until autopsy. Egg counts were not adjusted for the water content of the feces. Infections were assessed terminally by the number of live worms found at autopsy; following perfusion, the mesenteric and portal veins, the ground liver, and the perfusate were examined for schistosomes.

ANGIOSTRONGYLUS CANTONENSIS INFECTION IN RATS AND RHESUS MONKEYS, AND OBSERVATIONS ON THE SURVIVAL OF THE PARASITE IN VITRO.

Summary The slugs Limax maximus and Deroceras reticulatum were found to act as intermediate hosts for Angiostrongylus cantonensis. Infections in white rats were fatal when worm burdens reached 50 to 60 and above but became chronic and persisted for many months when 5 to 10 worms were present. Naturally-infected wild rats tend to have worm burdens which are similar to or somewhat higher than the latter. Discharge of first-stage larvae in feces of heavily infected white rats reached mean values of approximately 100,000 per ml of feces, whereas the mean for lightly infected rats ranged between 6,000 and 12,000 larvae per ml. One rat infected with 23 larvae developed paraplegia on the 31st day of infection. Experimental infections in monkeys with A. cantonensis did not give rise to overt symptoms. Four monkeys were necropsied, respectively, on days 17, 24, 32 and 69 after infection; fifth-stage worms were found in the brain of each except the last, in which there were, however, lesions consistent with the infection. The worms were retarded in development compared to those from rats sacrificed at similar time intervals and were also smaller than the ones recovered from a human brain. By day 17, parasites in the brain had elicited a diffuse and severe eosinophilic meningoencephalitis. The presence of foreign-body granulomas around dead parasites indicated that some must have entered the brain earlier. As the time interval between ingestion of the parasite and death of the animal increased, the inflammatory reaction changed from a diffuse eosinophilic to a more focal and granulomatous response. The latter was most frequently related to fragments of dead worm. Although lesions similar to those seen in the brain were found in the spinal cord of all monkeys, parasites were not found in the meninges and cord proper in any of the monkeys. Adult worms maintained in vitro survived best in medium NCTC 109 supplemented with serum. Maximum survival was 80 days for females and 64 days for males. Eggs deposited in vitro embryonated in 5 to 6 days, but only low percentages hatched. First-stage larvae cultured in vitro in various media showed no growth.