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L J Richardson

Publications and source records attributed to L J Richardson.

At least 19 recordsLinked to original sources
PubMed2007

Comparison of four sampling methods for the detection of Salmonella in broiler litter.

Experiments were conducted to compare litter sampling methods for the detection of Salmonella. In experiment 1, chicks were challenged orally with a suspension of naladixic acid-resistant Salmonella and wing banded, and additional nonchallenged chicks were placed into each of 2 challenge pens. Nonchallenged chicks were placed into each nonchallenge pen located adjacent to the challenge pens. At 7, 8, 10, and 11 wk of age the litter was sampled using 4 methods: fecal droppings, litter grab, drag swab, and sock. For the challenge pens, Salmonella-positive samples were detected in 3 of 16 fecal samples, 6 of 16 litter grab samples, 7 of 16 drag swabs samples, and 7 of 16 sock samples. Samples from the nonchallenge pens were Salmonella positive in 2 of 16 litter grab samples, 9 of 16 drag swab samples, and 9 of 16 sock samples. In experiment 2, chicks were challenged with Salmonella, and the litter in the challenge and adjacent nonchallenge pens were sampled at 4, 6, and 8 wk of age with broilers remaining in all pens. For the challenge pens, Salmonella was detected in 10 of 36 fecal samples, 20 of 36 litter grab samples, 14 of 36 drag swab samples, and 26 of 36 sock samples. Samples from the adjacent nonchallenge pens were positive for Salmonella in 6 of 36 fecal droppings samples, 4 of 36 litter grab samples, 7 of 36 drag swab samples, and 19 of 36 sock samples. Sock samples had the highest rates of Salmonella detection. In experiment 3, the litter from a Salmonella-challenged flock was sampled at 7, 8, and 9 wk by socks and drag swabs. In addition, comparisons with drag swabs that were stepped on during sampling were made. Both socks (24 of 36, 67%) and drag swabs that were stepped on (25 of 36, 69%) showed significantly more Salmonella-positive samples than the traditional drag swab method (16 of 36, 44%). Drag swabs that were stepped on had comparable Salmonella detection level to that for socks. Litter sampling methods that incorporate stepping on the sample material while in contact with the litter appear to detect Salmonella in greater incidence than traditional sampling methods of dragging swabs over the litter surface.

Animals↗
PubMed2006

Apparent attachment of Campylobacter and Salmonella to broiler breeder rooster spermatozoa.

It has been demonstrated that horizontal and vertical transmission of Salmonella and Campylobacter can occur in broiler breeder flocks. The mechanism of this transmission is still unclear. Previously negative broiler breeder flocks have been reported to become positive with Salmonella, Campylobacter, or both after the introduction of "spike" roosters at 45 wk of age. To determine whether the rooster semen is a possible source of transmission to hens for colonization, we evaluated the association of both Salmonella and Campylobacter spp. to segments (head, midpiece, and tail) of individual spermatozoa after artificial inoculation. Salmonella typhimurium, Salmonella heidelberg, and Salmonella montevideo, or Campylobacter jejuni (in 0.85% saline) was added to a freshly collected (by abdominal massage) aliquot of pooled semen from roosters housed in individual cages. The semen and bacteria solutions were incubated 1 h at room temperature. Samples were fixed using Karnosvsky and Zamboni fixatives for 24 h prior to centrifuging and rinsing in 0.1 M cacodylate x HCl buffer. Individual aliquot samples were then subjected to both scanning (JSM-5800) and transmission (JEM-1210) electron microscopy. The scanning electron microscopy showed that Salmonella was associated with all 3 segments (head, midpiece, and tail) of the spermatozoa and apparently equally distributed. Campylobacter was mainly associated with the midpiece and tail segments; few isolates were located on the head segment. The transmission electron microscopy showed apparent attachment of Salmonella and Campylobacter to the spermatozoa.

Animals↗
PubMed2006

Incidence of unabsorbed yolk sacs in broilers, broiler breeder roosters, white Leghorn hens, and Athens-Canadian randombred control broilers.

Unabsorbed yolk sacs are being investigated as a possible reservoir for internal Campylobacter and salmonellae contamination of processed poultry carcasses. However, it is unknown at what frequency that unabsorbed yolk sacs persist at the time of processing of broilers and spent breeders. Seven sets of 100 broiler carcasses (at 6 or 8 wk of age) were obtained from commercial processing plants. In addition, 100 52-wk-old broiler breeder males, 100 102-wk-old Leghorn hens, and 300 8-wk-old Athens-Canadian randombred control (ACRBC) broilers were euthanized, and their abdominal cavities were opened for determination of the presence of unabsorbed yolk sacs. Carcasses with obliterated yolk stalks or stalks with no detectable yolk material were categorized as normal. Those with unabsorbed yolk sacs were further separated into 2 groups: 1) attached by the yolk stalk to the small intestine or 2) unattached within the abdominal cavity. Yolk sacs were further classified by size: 1) small was <2 mm in diameter, 2) medium was 2 to 10 mm, and 3) large was >10 mm. From the 300 commercial broiler carcasses that were 6 wk old, 54% were categorized as normal with no detectable yolk sac, 35% had an unabsorbed yolk sac attached to the yolk stalk, and 12% had unattached yolk sacs. From the 400 commercial broiler carcasses that were 8 wk old, 49% of the carcasses were normal, 31% had attached unabsorbed yolk sacs, and 20% had unattached yolk sacs. From the 100 rooster carcasses sampled, 73% were normal, 8% had attached unabsorbed yolk sacs, and 19% had unattached yolk sacs. From the 100 White Leghorn hen carcasses sampled, 88% were normal, 8% had attached unabsorbed yolk sacs, and 4% were unattached yolk sacs. From the 300 ACRBC carcasses sampled, 76% were normal, 4% had attached unabsorbed yolk sacs, and 20% were unattached yolk sacs. The incidence of unabsorbed yolk sacs in present day commercial broilers appears twice as high as for mature roosters, hens, or ACRBC broilers.

Animals↗
PubMed2006

Detection of Campylobacter jejuni in various lymphoid organs of broiler breeder hens after oral or intravaginal inoculation.

Two studies were conducted to determine whether Campylobacter jejuni could rapidly spread and reside in the internal organs of adult broiler breeder hens. In Study 1, university-housed broiler breeders at 22 wk of age were obtained and placed in individual cages. Each hen was intravaginally inoculated weekly from 23 to 32 wk of age with a characterized strain of C. jejuni. At wk 23, 27, and 32, 4 d postinoculation, the hens were euthanized, defeathered, and aseptically opened. In Study 2, university-housed broiler breeder hens were obtained at 42, 53, and 56 wk of age, placed in individual cages, and inoculated either orally or intravaginally with a characterized strain of C. jejuni. To reduce the possibility of cross-contamination among samples, the thymus, spleen, liver, and gallbladder were aseptically removed, prior to the ceca. In both studies, all samples were individually analyzed. In Study 1, at 23 wk of age, C. jejuni was recovered from 4/7 thymii, 2/7 spleens, 5/7 livers and gallbladders, and 6/7 ceca. At 27 wk of age, C. jejuni was recovered from 1/7 thymii and 1/7 ceca. At 32 wk of age, C. jejuni was recovered from 4/11 thymii, 1/11 livers and gallbladders, and 2/11 ceca. In Study 2, C. jejuni was recovered from 2/6 thymii and 5/6 ceca after oral inoculation and 1/6 spleens, 1/6 livers and gallbladders, and 4/6 ceca after vaginal inoculation of 43-wk-old hens. Campylobacter jejuni was recovered from 2/5 thymii, 3/5 spleens, 3/5 livers and gallbladders, and 2/5 ceca after oral inoculation of 53-wk-old hens and 1/5 thymii and 1/5 livers and gallbladders after vaginal inoculation. Campylobacter jejuni was recovered from 1/4 thymii, 2/4 livers and gallbladders, and 1/4 ceca and was not detected in any vaginally inoculated birds of 57-wk-old hens. This study provides evidence that C. jejuni can reside in the internal organs of broiler breeder hens following oral or intravaginal inoculation.

Administration, Intravaginal↗
PubMed2006

Natural presence of Campylobacter spp. in various internal organs of commercial broiler breeder hens.

Campylobacter are known to cause acute bacterial gastroenteritis in humans. Poultry products have been implicated as a significant source of these infections. Six experiments were performed to determine whether Campylobacter could be isolated naturally from the primary and secondary lymphoid organs, liver/gallbladder, and ceca of commercial broiler breeder hens. Broiler breeder hens were acquired from different commercial sources during the early, middle, and late lay cycles. The birds were euthanatized, defeathered, and aseptically opened. To reduce the possibility of cross-contamination between samples, the thymus, spleen, and liver/gallbladder were aseptically removed prior to removal of the ceca. Individual samples were placed in sterile bags, packed on ice, and transported to the laboratory for evaluation. In this study Campylobacter were found in 11 of 43 thymii, eight of 43 spleens, four of 43 liver/gallbladders, and 30 of 43 ceca. Overall, 28 of 53 isolates from the above samples were Campylobacter coli and 25 of 53 isolates were found to be Campylobacter jejuni.

Animals↗
PubMed2006

Presence of inoculated Campylobacter and Salmonella in unabsorbed yolks of male breeders raised as broilers.

Day-old male broiler breeder chicks were obtained from a commercial hatchery and raised as broilers. For Experiment 1, at 5 wk of age, the broilers were orally inoculated with a 10(6) cfu/ml of a characterized strain of Campylobacter jejuni and a cocktail (three naladixic acid-resistant strains) of Salmonella serovars. One week after inoculation, the birds were euthanatized and defeathered. The abdominal cavity was examined and any unabsorbed yolk material (and remaining yolk stalk) and ceca were aseptically removed for microbiological analyses. For each pooled sample (two birds per pool), an aerobic plate count (APC), an Enterobacteriaceae (ENT) count, and a test for the presence of Campylobacter and Salmonella was performed. For Experiment 2, at 5 wk of age, the broilers were orally inoculated with 10(5) cfu/ml of a characterized strain of Campylobacter jejuni. One week after inoculation, the birds (n = 20) were killed, defeathered, and the yolk stalk, attached yolk, or free-floating yolk and ceca were individually analyzed for presence of Campylobacter. For Experiment 1, the Salmonella-inoculated birds had 2/12 ceca and 0/12 unabsorbed yolk samples positive for Salmonella. The average yolk APC was log10 3.4 cfu/g and the average ENT was log10 1.9 cfu/g. For the Campylobacter-inoculated birds, 12/12 ceca and 9/12 unabsorbed yolk samples were positive for Campylobacter. The average yolk APC was log10 3.5 cfu/g and the average ENT was log10 3.1 cfu/g. For Experiment 2, the inoculated Campylobacter birds had 19/20 ceca, 5/20 free floating yolks, and 19/20 yolk stalks positive. In Experiment 1, the inoculated Campylobacter colonized the ceca in every instance and were present in 75% of the unabsorbed yolks. Alternatively, the inoculated Salmonella were not found in any of the unabsorbed yolks and only rarely in the ceca. In Experiment 2, the inoculated Campylobacter was found in very high numbers in the yolk and internal body samples. Determining to what extent these internal bodies and unabsorbed yolks play in bacterial colonization and contamination of the birds at processing has not been determined. The next step will be to determine the incidence of unabsorbed yolks and presence of Campylobacter and Salmonella in these bodies of commercial broilers at processing.

Animal Husbandry↗
PubMed2005

Presence of Campylobacter jejuni in various organs one hour, one day, and one week following oral or intracloacal inoculations of broiler chicks.

Day-old broiler chicks (n=30) were obtained from a commercial hatchery and inoculated, either orally or intracloacally, with a characterized strain of Campylobacter jejuni. At 1 hr, 1 day, and 1 wk after inoculation, broilers (n = 5) from the orally and intracloacally inoculated groups along with control birds (n=4) were humanely killed by cervical dislocation. The broilers from the control and treatment groups were aseptically opened, and the thymus, spleen, liver/gallbladder, bursa of Fabricius, and ceca were aseptically removed and individually analyzed for C. jejuni. Overall, C. jejuni was isolated after oral inoculation from 13% (10/ 75), 17% (13/75), and 28% (14/50) of the 1-hr, 1-day, and 1-wk samples, respectively. Campylobacter jejuni was isolated from 10% (4/ 40), 8% (3/40), 10% (4/40), 25% (10/40), and 40% (16/40) of the thymus, spleen, liver/gallbladder, bursa of Fabricius, and ceca samples, respectively. Following the intracloacal route of inoculation, C. jejuni was recovered from 32% (24/75), 8% (6/75), and 16% (8/50) of the 1-hr, 1-day, and 1-wk samples, respectively. Campylobacter jejuni was isolated from 5% (2/40), 5% (2/40), 5% (2/40), 45% (18/40), and 40% (16/40) of the thymus, spleen, liver/gallbladder, bursa of Fabricius, and ceca samples, respectively, for all sampling periods. Campylobacter spp. were not recovered from sample sites examined from the control broilers from trial one, trial two, or trial three samples examined after 1 hr and 1 day. However, one control sample was positive from the 1-wk sampling from repetition three; therefore, those data were omitted. The rapid movement of Campylobacter to internal organs following both oral and intracloacal inoculation may be significant, particularly if it persists in these organs as reservoirs throughout the 65-wk life cycle of breeding birds.

Animals↗
PubMed2005

Presence of naturally occurring Campylobacter and Salmonella in the mature and immature ovarian follicles of late-life broiler breeder hens.

Campylobacter and Salmonella are known to cause acute bacterial gastroenteritis in humans. Raw poultry products have been implicated as a significant source of these infections. Five trials were conducted to determine whether Campylobacter and Salmonella spp. exist naturally in the mature and immature ovarian follicles of late-life broiler breeder hens. Broiler breeder hens ranging from 60 to 66 wk of age were obtained from four different commercial breeder operations. For each trial, the hens were removed from the commercial operation and held overnight at the University of Georgia processing facility. The hens were euthanized, defeathered, and aseptically opened. To reduce the possibility of cross-contamination between samples, first the mature and immature ovarian follicles, then the ceca, were aseptically removed. Individual samples were placed in sterile bags, packed on ice, and transported to the laboratory for evaluation. Overall, Campylobacter was found in 7 of 55 immature follicles, 12 of 47 mature follicles, and 41 of 55 ceca. Campylobacter was found in at least one of each sample of mature follicles and in ceca in each of the five trials. Salmonella was found in 0 of 55 immature follicles, 1 of 47 mature follicles, and 8 of 55 ceca. In this study, the recovery rate of Salmonella from late-life broiler breeder hen ovarian follicles was relatively low. However, the recovery rate of Campylobacter from the hen ovarian follicles was reasonably high, suggesting that these breeder hens could be infecting fertile hatching eggs. Determining how Campylobacter contaminated these ovarian follicles and how many chicks could be colonized from this source are the next steps in helping to elucidate a better understanding of this ecology and the control of Campylobacter in poultry production.

Animals↗
PubMed2005

Recovery of Campylobacter jejuni in feces and semen of caged broiler breeder roosters following three routes of inoculation.

We previously reported the recovery of Campylobacter (naturally colonized) from the ductus deferens of 5 of 101 broiler breeder roosters, and four of those five positive roosters had previously produced Campylobacter-positive semen samples. Those results prompted further evaluation to determine if inoculation route influenced the prevalence or level of Campylobacter contamination of semen, the digestive tract, or reproductive organs. Individually caged roosters, confirmed to be feces and semen negative for Campylobacter, were challenged with a marker strain of Campylobacter jejuni either orally using 1.0 ml of a diluted cell suspension (log(10)4.3 to 6.0 cells), by dropping 0.1 ml of suspension (log(10)5.3 to 7.0 cells) on the everted phallus immediately after semen collection or by dip coating an ultrasound probe in the diluted cell suspension (log(10)4.3 to 6.0 cells) and then inserting the probe through the vent into the colon. Six days postinoculation, individual feces and semen samples were again collected and cultured for Campylobacter. Seven days postinoculation, roosters were killed, the abdomen aseptically opened to expose the viscera, and one cecum, one testis, and both ductus deferens were collected. The samples were then suspended 1:3 (weight/volume) in Bolton enrichment broth for the culture of Campylobacter. Samples were also directly plated onto Cefex agar to enumerate Campylobacter. Campylobacter was recovered 6 days after challenge from feces in 82% of samples (log(10)4.1 colony-forming units [CFU]/g sample), 85% of semen samples (log(10)2.9 CFU/ml), and on the seventh day postchallenge from 88% of cecal samples (log(10)5.8 CFU/g sample). Campylobacter was not directly isolated from any testis sample but was detected following enrichment from 9% (3/33) of ductus deferens samples. Roosters challenged with Campylobacter orally, on the phallus, or by insertion of a Campylobacter dip-coated ultrasound probe were all readily colonized in the ceca and produced Campylobacter-positive semen and feces on day 6 after challenge. The low prevalence of recovery of Campylobacter from the ductus deferens samples and failure to recover from any testis sample suggests that semen may become Campylobacter positive while traversing the cloaca upon the everted phallus. The production of Campylobacter-positive semen could provide a route in addition to fecal-oral for the horizontal transmission of Campylobacter from the rooster to the reproductive tract of the hen.

Administration, Oral↗
PubMed2005

Movement and persistence of Salmonella in broiler chickens following oral or intracloacal inoculation.

The dissemination of Salmonella into various lymphoid-like organs in young broiler chicks after oral and intracloacal inoculation was studied. A three-strain cocktail of Salmonella Typhimurium, Salmonella Montevideo, and Salmonella Enteritidis was administered either orally or intracloacally to day-old chicks. After 1 h, 1 day, or 1 week, the ceca, thymus, liver and gallbladder, spleen, and bursa were sampled for the presence of Salmonella. There was a marked difference in the recovery of Salmonella 1 h postinoculation. Only 6 of 50 samples from orally inoculated chicks were positive compared with 33 of 50 samples from cloacally inoculated samples. In comparison, 24 h and 1 week after inoculation, there was no difference in the number of positive samples between oral or cloacal inoculation. The rapidity of the translocation of the Salmonella from the cloacal inoculum compared to the oral inoculum is likely due to the transient time required for Salmonella to move through the alimentary tract. The method of inoculation did not affect the distribution of serogroups. Of the three serotypes in the composite inoculum, the Salmonella Enteritidis (group D) was recovered only twice in replication 1 and not at all in replication 2. Both the Salmonella Typhimurium (serogroup B) and the Salmonella Montevideo (serogroup C1) were recovered extensively throughout the study.

Administration, Oral↗
PubMed2000

Unusual palatal presentation of oral psoriasis.

Oral lesions of psoriasis are rare clinical observations. Report on oral psoriasis that are well documented show no consistent lesion pattern. The oral lesions range in type from red plaques to white plaques to ulcers. In this report, an unusual palatal presentation of oral psoriasis with red serpiginous concentric arcs is described. The diagnosis of intraoral psoriasis is supported by clinical and microscopic findings.

Humans↗
PubMed1984

The roles of intrinsic kinase and of kinase/activator protein in the enhanced phosphorylation of pyruvate dehydrogenase complex in starvation.

Extracts of heart mitochondria from fed and from 48 h starved rats subjected to gel filtration on Sephacryl S-300 gave 4 major protein peaks. Pyruvate dehydrogenase complex eluted in the void volume and was assayed for intrinsic pyruvate dehydrogenase kinase activity which was increased approximately 3-fold by 48 h starvation of the rat. A second fraction, containing peaks 2 and 3 which overlapped, enhanced the activity of the intrinsic kinase and corresponds to kinase/activator protein described previously. Its activity was increased 1.5-fold by starvation.

Adenosine Triphosphate↗
PubMedDate not supplied

Effect of an electrostatic space charge system on airborne dust and subsequent potential transmission of microorganisms to broiler breeder pullets by airborne dust.

High levels of dust and microorganisms are known to be associated with animal confinement rearing facilities. Many of the microorganisms are carried by dust particles, thus providing an excellent vector for horizontal disease transmission between birds. Two environmentally controlled rooms containing female broiler breeder pullets (n = 300) were used to evaluate the effectiveness of an electrostatic space charge system (ESCS) in reducing airborne dust and gram-negative bacteria levels over an 8-wk period (starting when the birds were 10 wk old). The ESCS was used to evaluate the effectiveness of reducing airborne microorganism levels by charging airborne dust particles and causing the particles to be attracted to grounded surfaces (i.e., walls, floor, equipment). The use of the ESCS resulted in a 64% mean reduction in gram-negative bacteria. Airborne dust levels were reduced an average of 37% over a 1-wk period in the experimental room compared with the control room on the basis of samples taken every 10 min. The reductions of airborne dust and bacteria in this study are comparable with earlier results obtained with the ESCS in commercial hatching cabinets and experimental caged layer rooms, suggesting the system could also be applied to other types of enclosed animal housing.

Air Microbiology↗