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Detecting Salmonella in poultry feed is challenging. Studies have shown that preenrichment media lack the buffering capacity to prevent an acidic pH, which results in cell injury, death, or altered biochemical pathways preventing Salmonella detection. A tris phosphate carbonate (TPC) pre-enrichment medium has been developed to maintain a near-neutral pH during incubation of feed, but its utility has not been confirmed for a wide variety of feed and ingredients. Five-gram samples of feed ingredients (8 types) and corn- or wheat-based poultry feeds (10 types) were individually added to 45 mL of each of 5 different preenrichment broths: lactose broth (LB), buffered peptone water (BPW), double-strength buffered peptone water (2xBPW), universal pre-enrichment broth (UPB), and TPC. After incubation for 0, 18, 24, and 48 h at 37°C, the pH of each pre-enrichment was measured (5 replicates/treatment). Data were analyzed by the ANOVA and least significant difference T-test. The initial pH of the LB, BPW, 2xBPW, and UPB ranged from 6 to 7 for all ingredients and feeds. The initial pH of ingredients and feed in TPC was 8.0-8.4. After 24 h of incubation, the pH had decreased to 4.6-5.5 for LB and BPW. Variability was observed among feed types incubated in 2xBPW and UPB, where the pH ranged from 4.8 to 6.4 at 24 h. Tris phosphate carbonate was less variable than 2xBPW or UPB with the pH ranging from 6.5 to 7.4 at 24 h. Results suggest that pre-enrichment of a variety of feed in TPC provides a near-neutral pH throughout incubation and may improve the ability to recover Salmonella. [ABSTRACT FROM AUTHOR]

With the current researches on replacing antibiotics with different dietary interventions, bacteriophages (BP) are potential antimicrobial intervention because of their ability to affect specific bacteria. A study was conducted to evaluate the role of BP against Salmonella enterica serovar Enteritidis (SE) on SE internal organs colonization and ileum immune response in laying hens. Hens were challenged both orally and intracloacally with 108 cfu/mL cells of nalidixic acid resistant Salmonella Enteritidis (SENAR). Thirty-two Single Comb White Leghorns were randomly allocated to 4 dietary treatments: 1) unchallenged control (negative control; T1), 2) SENAR challenged control (positive control; T2), 3) SENAR challenged + 0.1% BP (T3), and 4) SENAR challenged + 0.2% BP (T4). The number of SENAR in the ceca was significantly reduced by 0.2% BP supplementation (P < 0.05) at 7 d post infection (dpi). The respective number of SENAR was reduced from 2.9 log cfu/gm in T2 and T3 to 2.0 log cfu/gm in T4. There was no significant effect of T3 on reduction of numbers of cecal SENAR. A significant reduction of SENAR was observed in the liver with gall bladder (LGB) from 0.75 in T2 to 0.18 log cfu/gm in T4. In the spleen, T4 significantly reduced (P < 0.05) SENAR to 0.56 log cfu/gm compared to T2 and T3 (0.94 log cfu/gm). There was no significant effect of T3 in reduction of prevalence of spleen SENAR. By supplementing 0.2% BP (T4), the SENAR in the ovary was reduced to 0 log cfu/gm. There was a significant reduction (P < 0.05) in fecal SENAR at 6 dpi by T4 (0.71 log cfu/gm) compared to the positive control (1.57 log cfu/gm). The expression of interferon (IFN)-Г, interleukin (IL)-6, and IL-10 was significantly increased in the ileum by SENAR challenge compared to the negative control. This study suggests that apart from commonly used prebiotics or probiotics, BP are pathogen-specific and can be used as one of the dietary strategies to reduce SE colonization and induce immune modulation in laying hens. [ABSTRACT FROM AUTHOR]

Evidence of Salmonella Enteritidis (SE) in internal organs of White Leghorns once they are inoculated via the oral (OR) or intracloacal (IC) route has not been consistently demonstrated. The aim of the current study was to evaluate OR or IC inoculation route of a nalidixic acid (Nal) resistant SE (SENAR) on the SE colonization of ceca and the invasion of internal organs in mature White Leghorns. Five experiments were conducted, and hens were inoculated with 108 colony-forming units (cfu) of SENAR. Hens were euthanized at 7 and 14 d post inoculation (dpi), and the ceca, spleen, liver with gall bladder (L/GB), and ovaries were collected for bacteriological analyses. The recovery of SENAR in ceca was 100% at 7 dpi. Recovery from the ovaries was lower than the other organs for both routes of inoculation. The SE recovery of L/GB, spleen, and ovaries at 7 dpi was not different between the two routes. By 14 dpi, all organs approached negative, and the recovery rate was similar between OR and IC. Fecal shedding was 100% positive at 3 dpi and reduced to almost 0% by 14 dpi. Mature hens were colonized by SENAR with either OR or IC inoculation when using a larger volume and a higher cfu/mL (0.1 mL OR in experiment 1 vs. 1.0 mL OR and IC in the rest). SENAR showed some translocation into other organs, to a greater extent with IC. The colonization did not persist either in ceca or the internal organs at 14 dpi. [ABSTRACT FROM AUTHOR]

There are multiple ways to sample broiler chicken carcasses for the prevalence of Salmonella. A common method in the USA is a whole carcass rinse and culture of an aliquot of the rinse. The objective of this study was to compare the sensitivity of the rinse aliquot method to overnight enrichment of the entire carcass in the rinse liquid. Fourteen replicate samplings of eight carcasses each were done at two commercial broiler processing plants. Carcasses were subjected to a whole carcass rinse in buffered peptone from which 30 mL was removed and added to 30 mL fresh buffered peptone (rinse aliquot sample). The aliquot sample and the carcass, in the remaining buffered peptone, were incubated overnight prior to standard selective enrichment and plating for Salmonella detection. Salmonella was detected in 15% of rinse aliquot samples and 59% of whole carcass enrichment samples. When detected by both methods, for the most part, the same serotypes were found on individual carcasses. Whole carcass enrichment was shown to be more sensitive than rinse aliquot method, and likely detects Salmonellae even when tightly bound to the carcass or present in very low numbers. As such, whole carcass enrichment is a useful research tool to determine Salmonella prevalence. Practical Applications Whole broiler carcass enrichment is a more sensitive method for detection of Salmonella than whole carcass rinse and aliquot incubation. Logistical requirements, however, make it impractical for routine or large scale investigations. Whole carcass enrichment has utility for research purposes to determine relative sensitivity of other methods or for testing of broiler processing microbial interventions. [ABSTRACT FROM AUTHOR]

Salmonella is a human pathogen that can accompany live broilers to the slaughter plant, contaminating fully processed carcasses. Feed is one potential source of Salmonella to growing broilers. Monitoring feed for the presence of Salmonella is part of good agricultural practice. The first step in culturing feed for Salmonella (which may be at low numbers and sub-lethally stressed) is to add it to a pre-enrichment broth which is incubated for 24 h. During the course of pre-enrichment, extraneous bacteria metabolize carbohydrates in some feed and excrete acidic byproducts, ausing the pH to drop dramatically. An acidic pre-enrichment pH can injure or kill Salmonella resulting in a failure to detect, even if it is present and available to infect chickens. The objective of this study was to test an array of buffering chemistries to prevent formation of an injurious acidic environment during pre-enrichment of feed in peptone water. Five grams of feed were added to 45 mL of peptone water buffered with carbonate, Tris pH 8, and phosphate buffering ingredients individually and in combination. Feed was subjected to a pre-enrichment at 35°C for 24 h; pH was measured at 0, 18, and 24 h. Standard phosphate buffering ingredients at concentrations up to 4 times the normal formulation were unable to fully prevent acidic conditions. Likewise, carbonate and Tris pH 8 were not fully effective. The combination of phosphate, carbonate, and Tris pH 8 was the most effective buffer tested. It is recommended that a highly buffered pre-enrichment broth be used to examine feed for the presence of Salmonella. [ABSTRACT FROM AUTHOR]

Abstract: There is limited information about Campylobacter in commercially processed quail (Coturnix coturnix). The objective of this study was to determine the occurrence of Campylobacter on carcasses in a commercial quail processing plant. Carcasses were collected prior to chilling and/or the application of any antimicrobials, transported to the laboratory, and individually bagged. Following the standard protocol for recovering Campylobacter, three typical colonies were selected, confirmed as Campylobacter and tested for antimicrobial susceptibility. Nine replicates were conducted. Of the 85 carcasses obtained (n = 5 for first visit, n = 10 for 8 subsequent visits), 28 (32.9%) carcasses were found to be positive for Campylobacter. On four visits, no Campylobacter was found; on two visits, all samples were positive; and 1/5, 1/10, and 6/10 samples were positive for the remaining visits. Of the 28 isolates recovered, 18 (64%) were C. jejuni and 10 (36%) were C. coli. Tetracycline resistance was detected in all 28 isolates. Future work in the breeder flocks, hatchery, and grow‐out houses is planned to further understand Campylobacter ecology in quail production and processing which could also be useful to the broiler industry. Practical applications: Very little published information exists for the presence of Campylobacter spp. on processed quail. Most of the studies involve cloacal swabs and ceca from samples obtained from hunters. This study involves sampling processed quail carcasses from a large commercial integrated company and also determined the species and antibiotic resistance profile of the Campylobacter isolates. There is considerable debate concerning the ecology of Campylobacter on poultry and perhaps our data can be used by the broiler industry to develop a better understanding of the ecology and to assist in the application of effective intervention strategies. Presently, there is slightly under 100,000 million commercially processed and domestically grown quails in the United States each year, most of which is marketed in Europe as a frozen product. So the presence of an important foodborne pathogen on this food is significant information. [ABSTRACT FROM AUTHOR]

A semi-quantitative ecometric technique was used to evaluate efficacy of selective culture media. It involved a standardized chronological streaking technique, leading to ever-decreasing number of colonies. The objective was to evaluate the efficacy of this technique (four-quandrant sequential streak [FQS]) with two commonly used Campylobacter broths (Bolton's and Tecra) with whole carcass rinses of post-pick broilers ( n = 30) obtained from a commercial processing plant. Ten ?L from each sample type was streaked (five individual streak lines) onto one quarter of a Campy-cefex agar plate and sequentially into the next three quadrants. Growth of extraneous bacteria was expressed as an absolute growth index (AGI). A significant ( P < 0.05) difference in background microflora suppression was observed using this procedure. A positive correlation between decreasing levels of background microflora within the broths was observed as the AGI declined. FQS can be used for rapid semi-quantitative estimation of an enrichment broth's efficacy. Practical applications The heavy presence of extraneous background microorganisms on a selective agar plate is a serious deterrent to the accurate detection of a target organism. This study confirmed sequential streaking as an appropriate and easily applied method to evaluate the relative efficiency of selective enrichment broths for Campylobacter in the suppression of background microflora on selective plates. The four-quadrant sequential streak (FQS) ecometric technique is an inexpensive, rapid, semi-quantitative method to evaluate the effectiveness of various selective enrichment broths. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Postchill neck skin maceration (NSM) and whole-carcass rinsing (WCR) are frequently used methods to detect salmonellae from processed broilers. These are practical, nondestructive methods, but they are insensitive and may result in false negatives (20 to 40%). Neck skin samples comprise only 4% of the skin from the broiler carcass by weight, while WCR will hot detect firmly attached Salmonella organisms and only 7.5% of the rinsate is utilized. Whole-carcass enrichment (WCE) involves incubation of the whole carcass overnight in a preenrichment broth and can recover as few as 8 inoculated Salmonella cells per carcass. The objective of this study was to use NSM, WCR, and WCE sampling to detect naturally occurring Salmonella from the same commercially processed broiler either prechill or postchill. Ten carcasses were obtained prechill and another 10 postchill on each of two replicate days from each of two commercial processing plants. From each carcass, 8.3 g of neck skin was sampled, and then the carcass was rinsed with 400 ml of 1% buffered peptone water. Thirty milliliters was removed and incubated (WCR), and the remaining 370 ml of broth and the carcass were incubated at 37°C for 24 h (WCE). Overall, Salmonella organisms were detected on 21, 24, and 32 of 40 prechill carcasses by NSM, WCR, and WCE, respectively, while 2, 2, and 19 of 40 postchill carcasses were positive by the respective methods. Prechill carcasses were 64% (77 of 120) positive for Salmonella, while postchill carcasses were 19% (23 of 120) positive. Commercial processing reduced the positive-sample prevalence by 45%. Salmonella organisms were detected on 20% (24 of 120) of the samples from plant 1 and 63% (76 of 120) of the carcasses from plant 2. This study demonstrates significant differences in the results for Salmonella prevalence among sampling methods both before and after immersion chilling, as well as between processing plants on days that samples were taken. [ABSTRACT FROM AUTHOR]

Many consumers assume that broiler chickens grown under traditional commercial conditions will have more Salmonella than free-range or organic chickens, which usually are less crowded, have access to outside spaces during grow out, and are fed special diets. Despite these perceptions, there is a lack of published information about the microbiological status of free-range and organic chickens. A total of 135 processed free-range chickens from four different commercial free-range chicken producers were sampled in 14 different lots for the presence of Salmonella. Overall, 9 (64%) of 14 lots and 42 (31%) of 135 of the carcasses were positive for Salmonella. No Salmonella were detected in 5 of the 14 lots, and in one lot 100% of the chickens were positive for Salmonella. An additional 53 all-natural (no meat or poultry meal or antibiotics in the feed) processed chickens from eight lots were tested; 25% of the individual chickens from 37% of these lots tested positive for Salmonella. Three lots of chickens from a single organic free-range producer were tested, and all three of the lots and 60% of the individual chickens were positive for Salmonella. The U.S. Department of Agriculture Food Safety and Inspection Service reported that commercial chickens processed from 2000 to 2003 had a Salmonella prevalence rate of 9.1 to 12.8%. Consumers should not assume that free-range or organic conditions will have anything to do with the Salmonella status of the chicken. [ABSTRACT FROM AUTHOR]

Poultry processors use antimicrobials to reduce the risk of pathogens on poultry and poultry products. The efficacy of selective and nonselective plating media to enumerate injured Salmonella (selective media— brilliant green sulfa agar and Petrifilm Enterobacteriaceae Plate Count; nonselective media—tryptic soy agar and Petrifilm Aerobic Plate Count) and Campylobacter (selective medium–Campy cefex agar and nonselective medium—Brucella agar) populations and the efficacy of peroxy acetic acid (PAA) to reduce Salmonella and Campylobacter populations on chicken breast fillets were evaluated. All plating media for Salmonella and Campylobacter contained nalidixic acid (200 ppm) or gentamycin (200 ppm), respectively. Breast fillets were sprayed or immersed in PAA (500 ppm) for 10 min for evaluation of the plating media. Breast fillets inoculated with a mixed Salmonella and Campylobacter cocktail were sprayed (5 or 10 s) or immersed (4–30 s) in PAA (100, 400, 500, or 1,000 ppm) for evaluation of PAA efficacy. Salmonella populations were higher (P 0.05) when plated on nonselective media compared with the selective media for the non-PAA treated fillets, although the differences in populations were low (,0.32 log CFU/mL). For both the microorganisms, populations on PAA treated (immersion or spray) fillets were similar when enumerated on nonselective or selective media within each treatment (PAA immersion or spray). Both immersion and spray applications reduced (P 0.05) the Salmonella and Campylobacter populations compared with the control. Increasing the PAA concentration to 250, 500, and 1,000 ppm resulted in greater reductions (P 0.05) in Salmonella and Campylobacter populations. Immersion of the inoculated breast fillets in 1,000 ppm PAA solution for 30 s resulted in Salmonella and Campylobacter population reductions of 1.92 and 1.87 log CFU/mL, respectively. Method of antimicrobial application (immersion and spray) did not affect the reductions in Salmonella and Campylobacter populations. Either immersion or spray application can be used to improve microbial safety of chicken breast fillets in a poultry processing plant. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the reduction of Campylobacter in livers treated with a low-pH processing aid, CMS PoultrypHresh, with and without a surfactant (PoultrypHresh Plus). Chicken livers (n = 36) were obtained from a local grocery; 13 livers were used in each of the 2 experimental treatment groups and 10 livers were used as untreated controls. Each liver was individually surface inoculated with a cell suspension of approximately 108 cells of a gentamicin-resistant Campylobacter coli marker strain in 0.1 mL of PBS. Cells were allowed 5 min to attach prior to treatment. Thirteen inoculated livers were individually placed into separate sterile specimen cups containing 100 mL of PoultrypHresh or PoultrypHresh Plus. Livers were subjected to a 15-s nonagitated dip before being removed and allowed 5 s to drain. Each liver was placed into an individual sterile specimen cup with 50 mL of buffered peptone water and hand shaken for 60 s. Untreated controls were treated as experimental samples, without undergoing any type of treatment dip. Rinsates were collected from each liver, serially diluted, and plated onto Campy Cefex agar with 200 ppm gentamicin. Plates were microaerobically incubated for 48 h at 42°C (5% O2, 10% CO2, and 85% N2); colonies were counted and the colony-forming units per milliliter was log transformed. On untreated livers, mean recovery was 5.51 log10 cfu/mL; using PoultrypHresh, a 1.66 log reduction (97.8%) was observed compared with untreated livers. With PoultrypHresh Plus there was a 2.16 log reduction (99.3%). This study demonstrated that the use of PoultrypHresh and PoultrypHresh Plus reduced numbers of C. coli on the surface of chicken livers by greater than 97.0%. No change in appearance was noted. [ABSTRACT FROM AUTHOR]

It is important to determine whether valuable broiler-breeder chicks are contaminated with Campylobacter. It is important to have a non-destructive method to determine whether microorganisms such as Campylobacter are present without sacrificing the animal. The objective of this study was to evaluate the reliability of cloacal swabs to detect Campylobacter in young chicks. Day-old chicks (n = 25) were gavaged with 101–3 or 106 Campylobacter coli (C. coli) gentamicin-resistant marker strain. Batches of chicks were placed in separate isolation units, and 7, 10, 14, or 21 d post challenge, 10 birds per group were cloacally swabbed shallow (9 mm) and deep (24 mm). Swabs were placed into 5 mL of Tecra® broth, vortexed, and streaked for isolation onto Campy Cefex agar plus 200 ppm of gentamicin. After swabbing, birds were sacrificed and one cecum was quantitatively analyzed for C. coli from the control group; both ceca from all challenged birds were analyzed for C. coli. At 14 d post challenge, 95% of the shallow and 90% of the deep swabs were positive. Even with a low inoculum of 103, C. coli achieved a high degree of cecal colonization, and the cloacal swab (either shallow or deep) proved reliable for detecting C. coli. Birds challenged with >102, after 7 and 14 d were colonized with >106 cells. After 7 d, all shallow and deep swabs were positive for C. coli, regardless of challenge dose. Since it might not be practical in industry to process the swabs the d of collection, we looked at the reliability of cloacal swabs after freezing for up to 21 days. When the level in the ceca was high, recovery of C. coli was excellent, but when the level was low (± 102 inoculum level), recovery was very unreliable. If the levels of Campylobacter are relatively high (log ≥ 6.0) in the ceca, both the shallow and deep swabs, unfrozen or frozen, are reliable, nondestructive methods to detect this microorganism. [ABSTRACT FROM AUTHOR]

Two experiments were conducted to determine the effect of an encapsulated sodium butyrate (Na-B) with targeted releasing times on broiler performance, energy digestibility, intestinal morphology, and ceca Salmonella colonization. In experiment 1, 3 different Na-B products (CMA, CMP, and CMS) were evaluated following a challenge with a nalidixic acid-resistant Salmonella typhimurium (STNAR). Cobb-Cobb male birds were placed 8 per pen into 6 replicates for each treatment. Treatments included 6 Na-B treatments (500 and 1,000 ppm of each product) plus 2 control (non-challenged and challenged). Birds were orally gavaged with 0.1 mL of 107 cfu/mL STNAR on d 4. Ceca and ileal samples were collected on d 11. In experiment 2, CMA and CMP products were evaluated for a full grow-out period without an external challenge. Cobb-Cobb male birds were distributed among 45 floor pens with 24 birds per pen. Treatments included 4 product treatments (500 and 1,000 ppm of each product) plus one control. Feed intake and pen weight were obtained on d 14, 28, and 42. Experiment 1 showed that CMP at 1,000 ppm had the highest value for BW and BWG on d 4 (P = 0.07). Adding CMA and CMP at 500 ppm increased ileal digestibility energy (IDE) compared to the challenged control (P ≤ 0.05). The Salmonella recovery data indicated that the challenge had a significant but mild impact, since it did not affect the performance variables but did result in a significant increase in log10 cfu/g cecal material between the nonchallenged and challenged control (1.42 vs 3.72). Experiment 2 showed that both products improved the villus height in the duodenum on d 21 (P = 0.08) and IDE on d 42, relative to the control (P ≤ 0.05). This study demonstrates that Na-B has the potential to improve growth in broilers at an early age. The beneficial effects on intestinal morphology and IDE are affected not only by dosage level, but also by the product's releasing time. [ABSTRACT FROM AUTHOR]

New regulations and performance standards for Campylobacter have been implemented by the USDA - Food Safety and Inspection Service (FSIS). The objective of this study was to evaluate treatment with a low pH processing aid (CMS1 PoultrypHresh), a formulated low pH processing aid, to reduce numbers of Campylobacter which could help companies meet regulatory requirements. Two experiments (3 replicates each) were conducted. Experiment 1, in each of 3 replicates, skin-on split chicken breasts (n = 15) were obtained from a local grocery and divided into groups of 5. The skin of each part was inoculated with approximately 107 cells of a gentamicin resistant C. coli (CC GR) marker strain in an area of approximately 6.5 cm2 CC GR cells were allowed to attach for 5 min prior to treatment. Ten inoculated breasts were individually placed into separate 6 L plastic storage boxes containing either 3.5 L deionized water or PoultrypHresh solution at a pH of 1.4. Parts were subjected to agitation (bubbled air) for 25 s. After treatment, each part was removed, allowed to drain for 5 s, and placed into a plastic bag prior to mechanical rinsing with 150 mL of buffered peptone water for 60 s. Five inoculated breasts served as controls, were untreated with a dip or agitation and sampled as above. Experiment 2 procedures were repeated using skin-on thighs under the same conditions. Rinsates were collected from each chicken part, serially diluted, and plated onto Campy Cefex agar with 200 ppm gentamicin (CCGen). All plates were incubated microaerobically (5% O2, 10% CO2, 85% N2) for 48 h at 42°C, colonies were counted and the cfu/mL was log transformed. The use of PoultrypHresh on split breast produced a 99.6% reduction compared to untreated controls, while thighs showed a 99.4% reduction. This study demonstrated an approximate 3 log reduction (P < 0.05) using a 25 s air agitation treatment in PoultrypHresh at pH 1.4 with no observable damage, which will help processors meet FSIS regulations. [ABSTRACT FROM AUTHOR]

It has been demonstrated that horizontal and vertical transmission of Salmonella and Cam pylobacter 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, Cam pylobacter, 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 Cam pylobacter spp. to segments (head, midpiece, and tail) of individual spermatozoa after artificial inoculation. Salmonella typhimurium, Salmonella heidelberg, and Salmonella montevideo, or Cam pylobacter 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-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 Cam pylobacter to the spermatozoa. [ABSTRACT FROM AUTHOR]

Quail (Coturnix japonica) is processed and marketed as fresh meat, with limited shelf life. The objective of this study was to evaluate the efficacy of antimicrobial interventions during slaughter on reducing Salmonella and Campylobacter contamination and to determine the microbiological shelf life of quail during refrigerated (4°C) storage. Three antimicrobials, peracetic acid (400 ppm; PAA), Citrilow (pH 1.2), and Cecure (cetylpyridinium chloride [CPC], 450 ppm), along with a water and no-treatment control were evaluated. Quail carcasses (n = 75) were inoculated with a cocktail of nalidixic acid-resistant Salmonella Typhimurium and gentamicin-resistant Campylobacter coli. After 30 min of attachment time, quail carcasses were submerged in each antimicrobial solution for 20 s with air agitation. Noninoculated quail carcasses (n = 25) were similarly treated, packaged, and stored under refrigeration (4°C). Aerobic plate counts (APC), psychrotroph counts (PC), Enterobacteriaceae counts (ENT), total coliform counts (TCC), and Escherichia coli counts on quail carcasses were determined on 1, 4, 7, and 10 d. Salmonella and Campylobacter populations were determined by plating on Petrifilm APC supplemented with 200-ppm nalidixic acid and Campy Cefex agar supplemented with 200-ppm gentamycin, respectively. No significant reductions in (P > 0.01 log cfu/mL) in APC, PC, ENT, TCC, and E. coli counts were observed on carcasses submerged in water. However, treatments with PAA, Citrilow, and CPC significantly reduced (P ≤ 0.05) Salmonella and Campylobacter coli contamination. Citrilow showed greater (P ≤ 0.05) reduction in Salmonella and Campylobacter population (1.90 and 3.82 log cfu/mL reduction, respectively) to PAA and CPC. Greater (P ≤ 0.05) reductions in APC, PC, ENT, TCC, and E. coli counts (2.22, 1.26, 1.47, 1.52, and 1.59 log cfu/mL, respectively) were obtained with the application of CPC. Application of antimicrobial interventions resulted in a reduction in Campylobacter and Salmonella, APC, PC, and ENT populations after treatments (day 0) and throughout the storage period (day 10). Use of antimicrobial interventions after slaughter can improve the microbiological safety and shelf life of quail., (Copyright © 2020. Published by Elsevier Inc.)

Sixteen sites in the watershed of the South Fork of the Broad River (SFBR) in Northeastern Georgia, USA, were sampled in two seasons to detect Campylobacter. Sites were classified as mostly influenced by forest, pasture, wastewater pollution control plants (WPC) or mixed use. Sampling was repeated in the late spring and late fall for 2 years for a total of 126 samples. Free-catch water and sediment grab samples were taken at each site; Moore's swabs were placed for up to 3 days at most sites. A total of 56 isolates of thermophilic Campylobacter were recovered. Thirteen samplings were positive by two or three methods, and 26 samplings were positive by only one method; once by Moore's swab only and 25 times by free-catch water only. Campylobacter was detected at 58% of cattle pasture sites, 30% of forested sites and 81% of WPC sites. Twenty-one of the isolates carried antimicrobial resistance genes, mostly blaOXA-61. Free-catch water samples were more efficient than Moore's swabs or sediment samples for recovery of Campylobacter, which was more likely to be detected in streams near cattle pastures and human communities than in forested land. SIGNIFICANCE AND IMPACT OF THE STUDY: The role of environmental water in transmitting Campylobacter was investigated, and methods for recovery of the organism were compared. The sequence types of recovered Campylobacter correlated with adjacent land use without regard to the method used to isolate the organisms. Sequence types and antimicrobial resistance genes associated with cattle were most prevalent near pastures. Even though types were recurrent at a given site, types appeared to be lost or replaced as the water flowed downstream., (Published 2019. This article is a U.S. Government work and is in the public domain in the USA.)

Poultry processors use antimicrobials to reduce the risk of pathogens on poultry and poultry products. The efficacy of selective and nonselective plating media to enumerate injured Salmonella (selective media-brilliant green sulfa agar and Petrifilm Enterobacteriaceae Plate Count; nonselective media-tryptic soy agar and Petrifilm Aerobic Plate Count) and Campylobacter (selective medium-Campy cefex agar and nonselective medium-Brucella agar) populations and the efficacy of peroxy acetic acid (PAA) to reduce Salmonella and Campylobacter populations on chicken breast fillets were evaluated. All plating media for Salmonella and Campylobacter contained nalidixic acid (200 ppm) or gentamycin (200 ppm), respectively. Breast fillets were sprayed or immersed in PAA (500 ppm) for 10 min for evaluation of the plating media. Breast fillets inoculated with a mixed Salmonella and Campylobacter cocktail were sprayed (5 or 10 s) or immersed (4-30 s) in PAA (100, 400, 500, or 1,000 ppm) for evaluation of PAA efficacy. Salmonella populations were higher (P ≤ 0.05) when plated on nonselective media compared with the selective media for the non-PAA treated fillets, although the differences in populations were low (<0.32 log CFU/mL). For both the microorganisms, populations on PAA treated (immersion or spray) fillets were similar when enumerated on nonselective or selective media within each treatment (PAA immersion or spray). Both immersion and spray applications reduced (P ≤ 0.05) the Salmonella and Campylobacter populations compared with the control. Increasing the PAA concentration to 250, 500, and 1,000 ppm resulted in greater reductions (P ≤ 0.05) in Salmonella and Campylobacter populations. Immersion of the inoculated breast fillets in 1,000 ppm PAA solution for 30 s resulted in Salmonella and Campylobacter population reductions of 1.92 and 1.87 log CFU/mL, respectively. Method of antimicrobial application (immersion and spray) did not affect the reductions in Salmonella and Campylobacter populations. Either immersion or spray application can be used to improve microbial safety of chicken breast fillets in a poultry processing plant., (Copyright © 2020. Published by Elsevier Inc.)

The BAX system with automated PCR detection was compared with standard cultural procedures for the detection of naturally occurring and spiked Salmonella in 183 chicken carcass rinses and 90 chicken hot dogs. The automated assay procedure consists of overnight growth (16 to 18 h) of the sample in buffered peptone broth at 35 degrees C, transfer of the sample to lysis tubes, incubation and lysis of the cells, transfer of the sample to PCR tubes, and placement of tubes into the cycler-detector, which runs automatically. The automated PCR detection assay takes about 4 h after 16 to 24 h of overnight preenrichment. The culture procedure consists of preerichment, enrichment, plating, and serological confirmation and takes about 72 h. Three trials involving 10 to 31 samples were carried out for each product. Some samples were spiked with Salmonella Typhimurium, Salmonella Heidelberg, Salmonella Montevideo, and Salmonella Enteritidis at 1 to 250 cells per ml of rinse or 1 to 250 cells per g of meat. For unspiked chicken rinses, Salmonella was detected in 2 of 61 samples with the automated system and in 1 of 61 samples with the culture method. Salmonella was recovered from 111 of 122 spiked samples with the automated PCR system and from 113 of 122 spiked samples with the culture method. For chicken hot dogs, Salmonella was detected in all 60 of the spiked samples with both the automated PCR and the culture procedures. For the 30 unspiked samples, Salmonella was recovered from 19 samples with the automated PCR system and from 10 samples with the culture method. The automated PCR system provided reliable Salmonella screening of chicken product samples within 24 h.

The subtyping and identification of bacterial pathogens throughout food processing and production chains is useful to the new hazard analysis critical control point-based food safety plans. Traditional manual serotyping remains the primary means of subtyping Salmonella isolates. Molecular biology techniques, however, offer the promise of more rapid and sensitive subtyping of Salmonella. This study evaluates the potential of restriction enzyme PvuII, followed by probing with the rRNA operon from Escherichia coli, to generate serotype-specific DNA fingerprints. A total of 32 identified serotypes were found with an overall agreement in 208 of the 259 (80%) isolates tested between U.S. Department of Agriculture serotype identification and riboprint serotype identification. Many of the isolates that did not correlate were serotype identified as Salmonella Montevideo, which indicates that for this serotype, there are multiple ribotypes. When Salmonella Montevideo isolates were not included, the ribotype identification agreed with serotyping in 207 of the 231 (90%) isolates. The primary outcome of any ribotyping procedure is to give distinct ribotype patterns. This extensive poultry epidemiological study demonstrates that, in addition to ribotype patterns, the identification of isolates to known serotypes provides the investigator with additional information that can be more useful than traditional epidemiology and isolate identification studies.

The widespread presence of Salmonella in all phases of broiler chicken production and processing is well documented. However, little information is available to indicate the identity and movement of specific serotypes of Salmonella through the different phases of an integrated operation. In this study, samples were collected from the breeder farm, from the hatchery, from the previous grow-out flock, from the flock during grow-out, and from carcasses after processing. Salmonella were recovered from 6, 98, 24, 60, and 7% of the samples, respectively, in the first trial and from 7, 98, 26, 22, and 36% of the samples, respectively, in the second trial. Seven different serotypes were identified in the first trial, and 12 different serotypes were identified in the second trial. For both trials there was poor correlation between the serotypes found in the breeder farms and those found in the hatchery. This finding and the fact that similar serotypes were found in the hatchery in both trials suggests that there was an endemic population of Salmonella in the hatchery. An association between the serotypes found in the hatchery and those found on the final processed carcasses was observed in both trials. This study confirms that a successful intervention program for broiler production operations must be multifaceted, with one component being disinfection in the hatchery.

The prevalence of Salmonella from numerous sources in 32 integrated broiler operations of high- and low-performing broiler houses was characterized from four states across four seasons. Previous studies of Salmonella in broilers have been limited in scope, offering only a snapshot of pathogen prevalence as seen on a small number of individual farms. Twenty-six different sample types were collected from the hatchery to the end of processing, and Salmonella was found in all sample types. A total of 10,740 samples were analyzed for Salmonella, and 973 (9.1%) of these samples, including 49 of 798 (6.1%) carcass rinse samples, were Salmonella positive. Hatchery transport pads (389 of 765, 50.8%), flies (28 of 150, 18.7%), drag swabs (57 of 402, 14.2%), and boot swabs (20 of 167, 12%) were samples from which Salmonella was most frequently isolated. Thirty-six different serotypes were identified, and the most frequently encountered serotypes were Salmonella Senftenberg, Salmonella Thompson, and Salmonella Montevideo. Determining critical contaminating sources and following the movement of Salmonella through integrated poultry operations will help researchers and the industry develop practical intervention strategies.