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Background Microbial endocrinology, which is the study of neuroendocrine-based interkingdom signaling, provides a causal mechanistic framework for understanding the bi-directional crosstalk between the host and microbiome, especially as regards the effect of stress on health and disease. The importance of the cecal microbiome in avian health is well-recognized, yet little is understood regarding the mechanisms underpinning the avian host-microbiome relationship. Neuroendocrine plasticity of avian tissues that are focal points of host-microbiome interaction, such as the gut and lung, has likewise received limited attention. Avian in vivo models that enable the study of the neuroendocrine dynamic between host and microbiome are needed. As such, we utilized Japanese quail (Coturnix japonica) that diverge in corticosterone response to stress to examine the relationship between stress-related neurochemical concentrations at sites of host-microbe interaction, such as the gut, and the cecal microbiome. Results Our results demonstrate that birds which contrast in corticosterone response to stress show profound separation in cecal microbial community structure as well as exhibit differences in tissue neurochemical concentrations and structural morphologies of the gut. Changes in neurochemicals known to be affected by the microbiome were also identified in tissues outside of the gut, suggesting a potential relationship in birds between the cecal microbiome and overall avian physiology. Conclusions The present study provides the first evidence that the structure of the avian cecal microbial community is shaped by selection pressure on the bird for neuroendocrine response to stress. Identification of unique region-dependent neurochemical changes in the intestinal tract following stress highlights environmental stressors as potential drivers of microbial endocrinology-based mechanisms of avian host-microbiome dialogue. Together, these results demonstrate that tissue neurochemical concentrations in the avian gut may be related to the cecal microbiome and reveal the Japanese quail as a novel avian model in which to further examine the mechanisms underpinning these relationships.

SUMMARY: Novel protein feeds are needed in ecological and organic poultry production to supply natural sources of amino acids, particularly methionine. Synthetic amino acids are increasingly banned in certified organic production. Carp is an invasive fish in the United States and its harvest can help provide natural source of methionine, while reducing an undesirable population. In our previous study, we formulated a diet using extruded carp-based meal (CBM) to replace synthetic methionine in broiler diets and conducted a feeding trial to test its effect on broiler performance. For this study, birds were processed at the end of the feeding trial and evaluated for quality and sensory attributes of meat from birds fed with CBM diet. Controls were normal diet that contained methionine and the carp meal was used to replace methionine and a portion of soybean meal. Results suggest that birds fed with CBM diet did not differ from the Control in live weight, carcass weight, breast weight, ready-to-cook yield, wing yield, tenders, and thigh yields (P > 0.05). Breast meat was more light (L*) for birds from the CBM treatment compared to the Control and the pH was lower (P < 0.05). For the thigh meat, birds fed CBM diets resulted in higher protein and less fat compared to the Control (P < 0.05). In the consumer analysis, overall impression, flavor, and mouthfeel were lower for the CBM breast meat than the Control and scored lower in terms of tenderness and juiciness (P < 0.05). Interestingly, thigh meat from CBM had more omega-3 fatty acids, which has a human health benefit. The results indicate that carp-based meal hold potential as a novel protein to replace synthetic methionine in organic broiler diets.

The study of neurochemical-based interkingdom signaling and its impact on host-microbe interaction is called microbial endocrinology. Neurochemicals play a recognized role in determining bacterial colonization and interaction with the gut epithelium. While much attention has been devoted to the determination of neurochemical concentrations in the mammalian gut to better understand tissue and region-specific microbial endocrinology-based mechanisms of host-microbe interaction, little is known regarding the biogeography of neurochemicals in the avian gut. Greater resolution of avian gut neurochemical concentrations is needed especially as recent microbial endocrinology-based investigations into bacterial foodborne pathogen colonization of the chicken gut have demonstrated neurochemicals to affect Campylobacter jejuni and Salmonella spp. in vivo and in vitro. The aim of the present study was to determine the concentrations of stress-related neurochemicals in the tissue and luminal content of the duodenum, jejunum, ileum, cecum, and colon of the broiler intestinal tract, and to investigate if this biogeography changes with age of the bird. While all neurochemicals measured were detected in the intestinal tract, many displayed differences in regional concentrations. Whereas the catecholamine norepinephrine was detected in each region of the intestinal tract, epinephrine was present only in the cecum and colon. Likewise, dopamine, and its metabolite 3,4-dihydroxyphenylacetic acid were found in the greatest quantities in the cecum and colon. Serotonin and histamine were identified in each gut region. Region-specific age-related changes were observed (P < 0.05) for serotonin, its metabolite 5-hydroxyindole acetic acid as well as for histamine. Several neurochemicals, including norepinephrine, were found in the contents of each gut region. Epinephrine was not detected in the gut content of any region. Salsolinol, a microbial-produced neuroactive compound was detected in the gut content but not in tissue. Together, our data establish a neurochemical biogeography of the broiler chicken intestinal tract. By providing researchers with a region-by-region map of in vivo gut neurochemical concentrations of a modern broiler chicken breed, this neurochemical map is expected to inform future investigations that seek to utilize avian enteric neurochemistry.

SUMMARY High-quality protein feeds are needed in ecological and organic poultry production. Feeds that are rich in methionine (MET) are particularly important because synthetic amino acids are generally prohibited in organic livestock production. Bigheaded carp present an opportunity as feed because they are an invasive fish species that are high in protein and MET. A carp-based meal (CBM) was prepared using innovative dry extrusion, and proximate analysis and nutritional analyses were conducted. The digestible amino acids and true metabolizable energy (TMEn) of the CBM were determined using a colony of cecetomized adult roosters. Starter and grower diets were formulated with CBM and tested in a broiler feeding trial. Diets were high overall in protein, but formulated without synthetic MET. Day-old chicks were randomly assigned to pens of 30 chicks belonging to 1 of 2 treatments (CBM or control containing synthetic MET), with 8 replications. Body weights, feed intake, and feed conversion ratio (FCR) for starter (0–21 d), grower (22–42 d), and overall periods (0–42 d) were analyzed using 1-way ANOVA. The weight gains, feed intake, and FCR did not differ between treatments (P > 0.05) for the overall period (0–42 d). The results indicate that invasive bigheaded carp can be harvested and dry extruded into a novel meal, providing not only a natural and sustainable source of MET, but also an environmental service for damaged aquatic ecosystems in the U.S.

SUMMARY Drinking water contaminated with Salmonella could serve as a source for cecal colonization of the pathogen in birds. In this study, we investigated the efficacy of a generally recognized as safe—status essential oil (lemongrass essential oil, LGEO) against multidrug-resistant Salmonella enterica serovar Heidelberg (S. Heidelberg) in poultry drinking water. Farm water with and without added droppings, litter, or feed [0.5% (w/v)] inoculated with 6.0 log10 cfu/mL S. Heidelberg was treated with 0, 0.03, 0.06, 0.125, 0.25, or 0.5% (v/v) LGEO and incubated at 12.5°C or 22°C for up to 7 d. The number of viable S. Heidelberg populations was determined on d 0, 1, 3, 5, and 7. At 12.5°C, all concentrations of LGEO inactivatedS. Heidelberg to non-detectable levels in water alone and water contaminated with droppings or litter by d 7 (>6 log10 cfu/mL; P 5.0 log10 cfu/mL reduction of S. Heidelberg on d 7 in water contaminated with feed (P 6 log10 cfu/mL; P 5.0 log10 cfu/mL reduction of S. Heidelberg in water contaminated with litter on d 7 (P

Salmonella Enteritidis is an intracellular foodborne pathogen that has developed multiple mechanisms to alter poultry intestinal physiology and infect the gut. Short chain fatty acid butyrate is derived from microbiota metabolic activities, and it maintains gut homeostasis. There is limited understanding on the interaction between S. Enteritidis infection, butyrate, and host intestinal response. To fill this knowledge gap, chicken macrophages (also known as HTC cells) were infected with S. Enteritidis, treated with sodium butyrate, and proteomic analysis was performed. A growth curve assay was conducted to determine sub-inhibitory concentration (SIC, concentration that do not affect bacterial growth compared to control) of sodium butyrate against S. Enteritidis. HTC cells were infected with S. Enteritidis in the presence and absence of SIC of sodium butyrate. The proteins were extracted and analyzed by tandem mass spectrometry. Our results showed that the SIC was 45 mM. Notably, S. Enteritidis-infected HTC cells upregulated macrophage proteins involved in ATP synthesis through oxidative phosphorylation such as ATP synthase subunit alpha (ATP5A1), ATP synthase subunit d, mitochondrial (ATP5PD) and cellular apoptosis such as Cytochrome-c (CYC). Furthermore, sodium butyrate influenced S. Enteritidis-infected HTC cells by reducing the expression of macrophage proteins mediating actin cytoskeletal rearrangements such as WD repeat-containing protein-1 (WDR1), Alpha actinin-1 (ACTN1), Vinculin (VCL) and Protein disulfide isomerase (P4HB) and intracellular S. Enteritidis growth and replication such as V-type proton ATPase catalytic subunit A (ATPV1A). Interestingly, sodium butyrate increased the expression of infected HTC cell protein involving in bacterial killing such as Vimentin (VIM). In conclusion, sodium butyrate modulates the expression of HTC cell proteins essential for S. Enteritidis invasion.

Salmonella Enteritidis (SE) is a facultative intracellular pathogen that colonizes the chicken gut leading to contamination of carcasses during processing. A reduction in intestinal colonization by SE could result in reduced carcass contamination thereby reducing the risk of illnesses in humans. Short chain fatty acids such as butyrate are microbial metabolites produced in the gut that exert various beneficial effects. However, its effect on SE colonization is not well known. The present study investigated the effect of sub-inhibitory concentrations (SICs) of sodium butyrate on the adhesion and invasion of SE in primary chicken enterocytes and chicken macrophages. In addition, the effect of sodium butyrate on the expression of SE virulence genes and selected inflammatory genes in chicken macrophages challenged with SE were investigated. Based on the growth curve analysis, the two SICs of sodium butyrate that did not reduce SE growth were 22 and 45 mM, respectively. The SICs of sodium butyrate did not affect the viability and proliferation of chicken enterocytes and macrophage cells. The SICs of sodium butyrate reduced SE adhesion by ∼1.7 and 1.8 Log CFU/mL, respectively. The SE invasion was reduced by ∼2 and 2.93 Log CFU/mL, respectively in chicken enterocytes (P < 0.05). Sodium butyrate did not significantly affect the adhesion of SE to chicken macrophages. However, 45 mM sodium butyrate reduced invasion by ∼1.7 Log CFU/mL as compared to control (P < 0.05). Exposure to sodium butyrate did not change the expression of SE genes associated with motility (flgG, prot6E), invasion (invH), type 3 secretion system (sipB, pipB), survival in macrophages (spvB, mgtC), cell wall and membrane integrity (tatA), efflux pump regulator (mrr1) and global virulence regulation (lrp) (P > 0.05). However, a few genes contributing to type-3 secretion system (ssaV, sipA), adherence (sopB), macrophage survival (sodC) and oxidative stress (rpoS) were upregulated by at least twofold. The expression of inflammatory genes (Il1β, Il8, and Mmp9) that are triggered by SE for host colonization was significantly downregulated (at least 25-fold) by sodium butyrate as compared to SE (P < 0.05). The results suggest that sodium butyrate has an anti-inflammatory potential to reduce SE colonization in chickens.

Four wild-type Campylobacter jejuni strains isolated from the cecal contents of broiler chickens were sequenced. The average genome size was 1,622,170 bp, with 1,667 to 1,761 coding sequences and 47 to 51 RNAs. Multiple genes encoding motility, intestinal colonization, toxin production, stress tolerance, and multidrug resistance were present in all the strains.

SUMMARY Organic poultry production is based on ecological processes, such as nutrient cycling, and reduces the use of synthetic inputs. High-quality protein feeds are needed to provide essential amino acids for poultry, particularly methionine. Although synthetic methionine is currently allowed in poultry feeding in the US organic program, sources that are natural are needed. Fishmeal is a high-quality protein and contains methionine; however, fishmeal sources are limited and may not be sustainable or local. A possible source of fishmeal in the USA is Asian carp fishmeal. Asian carp have invaded the Mississippi river basin with negative impacts on native fish and riparian ecosystems, and harvesting the carp may be a management strategy to help control it. Additional options for high-quality protein feeds include invertebrate meals from mass insect production, such as black soldier fly larvae, and worms. These can be raised sustainably for poultry feed by using crop by-products, residues, or recycled food to reduce food waste. Alternative feeding methods may be helpful to utilize these innovative feeds. Alternative protein feeds can contribute to ecological poultry production and have an important role under certified organic standards.

Objective Determination of feasibility of online nutrition education in the federal workplace. Design Pretest–posttest pilot study with data collection occurring from September to December, 2016. Setting Two US Department of Agriculture workplaces. Participants Convenience sample of 26 federal government employees. Posttest response rate was 85% (22 of 26 employees). Intervention A 12-week online nutrition education program designed and taught by registered dietitian nutritionists. Variables Measured Program component satisfaction, use, and understanding ratings and clinical measures including body composition, blood pressure, and skin carotenoid level (biomarker for fruit and vegetable intake). Analysis Paired t tests to determine whether significant changes occurred after the intervention. Results Mean number of class videos viewed and program components used were 7 and 5 (out of 12 for both). Mean program component ratings ranged from 4.0 to 4.7 (n = 12, maximum score of 5) for the surveyitems motivated/helped me to eat healthier. Statistically significant decreases were observed in body mass index, percent body fat, and visceral fat level. Conclusions and Implications Online nutrition education in the federal workplace is feasible for some employees as evidenced by the program components’ high satisfaction and understanding ratings and high retention rate. Limited evidence was apparent for the intervention's positive impact on health outcomes.

SUMMARY Currently, there is little scientific information regarding the effect of differing housing types and production methods on the final quality of broiler meat. The purpose of this study was to evaluate meat quality characteristics of commercial fast-growing broiler chickens when raised in portable vs. fixed housing, with or without access to pasture. Fast-growing broilers are being grown by many small farm poultry producers due to their favorable attributes, including greater breast meat yields, a more uniform carcass, and higher feed efficiency than heritage or slower growing breeds. The pasture land used in this study closely matched the lands common to this local area. It was a pasture composed of a mix of tall fescue, Bermuda grass, and a lesser amount of legumes and forbs. The experiment had 4 treatment groups: (1) small, portable hoop houses with access to pasture, (2) small, portable hoop houses without access to pasture, (3) a fixed house with access to the outdoors, and (4) a fixed house without access to the outdoors. The study was conducted during spring and fall within the same yr to evaluate if any seasonal effects on carcass or meat quality were present. Overall, the access to pasture did not alter meat quality parameters such as moisture, protein, fat percentage, pH, color, texture, cooking loss, or shear energy when compared to birds without pasture access. Since forages contribute to the nutritive value of the meat and may help in reducing costs, the type and quality of forage choices in pastures are important considerations for these production methods and need to be explored further for pasture production systems.

Heat stress (HS) is devastating to poultry production worldwide, yet its biology and molecular responses are not well defined. Although advances in management strategy have partially alleviated the negative impact of HS, productivity still continues to decline when the ambient temperature rises. Therefore, identifying mechanism-based approaches to decrease HS susceptibility while improving production traits is critical. Recently, we made a breakthrough by applying a surface wetting strategy and showing that it improves growth performance compared with the current conventional cooling system. In the present study, we aimed to further define molecular mechanisms associated with surface wetting in ameliorating HS productivity loss in broilers. Five-week-old broiler chickens were exposed to acute HS (35°C for 2 h) alone or in combination with surface wetting. A control group was maintained at thermoneutral conditions (25°C). Core body temperature (BT) and feed intake were recorded. Blood was collected and hypothalamic tissues (main site involved in the regulation of energy homeostasis) were harvested to determine the expression profile of stress- and metabolic-related genes. Surface wetting prevents HS from increasing BT and plasma corticosterone levels ( < 0.05) and improves feeding and drinking behaviors. At molecular levels, surface wetting blocks the activation of hypothalamic heat shock protein and adenosine monophosphate-activated protein-induced by HS and significantly modulates the expression of feeding-related hypothalamic neuropeptides (agouti-related protein, proopiomelanocortin, orexin, orexin receptor, and leptin receptor). Taken together, our data represent the first evidence that surface wetting alleviates systemic and intracellular stress induced by HS and preserves the intracellular energy status, which, in turn, may result in improved broiler well-being and growth performance.

Background Three-dimensional models of cell culture such as organoids and mini organs accord better advantage over regular cell culture because of their ability to simulate organ functions hence, used for disease modeling, metabolic research, and the development of therapeutics strategies. However, most advances in this area are limited to mammalian species with little progress in others such as poultry where it can be deployed to study problems of agricultural importance. In the course of enterocyte culture in chicken, we observed that intestinal mucosal villus-crypts self-repair and form spheroid-like structures which appear to be useful as ex vivo models to study enteric physiology and diseases. Results The villus-crypts harvested from chicken intestinal mucosa were cultured to generate enteroids, purified by filtration then re cultured with different chemicals and growth factors to assess their response based on their morphological dispositions. Histochemical analyses using marker antibodies and probes showed the enteroids consisting different cell types such as epithelial, goblet, and enteroendocrine cells typical to villi and retain functional characteristics of intestinal mucosa. Conclusions We present a simple procedure to generate avian crypt-villous enteroids containing different cell types. Because the absorptive cells are functionally positioned outwards, similar to the luminal enterocytes, the cells have better advantages to interact with the factors present in the culture medium. Thus, the enteroids have the potential to study the physiology, metabolism, and pathology of the intestinal villi and can be useful for preliminary screenings of the factors that may affect gut health in a cost-effective manner and reduce the use of live animals.

Campylobacter jejuni is a major foodborne pathogen that causes gastroenteritis in humans. Chickens act as the reservoir host for C. jejuni, wherein the pathogen asymptomatically colonizes the ceca leading to contamination of carcasses during slaughter. The major colonization factors in C. jejuni include motility, intestinal epithelial attachment, acid/bile tolerance, and quorum sensing. Reducing the expression of the aforementioned factors could potentially reduce C. jejuni colonization in chickens. This study investigated the efficacy of subinhibitory concentration (SIC; compound concentration not inhibiting bacterial growth) of carvacrol in reducing the expression of C. jejuni colonization factors in vitro. Moreover, the effect of carvacrol on the expression of C. jejuni proteome was investigated using liquid chromatography-tandem mass spectrometry. The motility assay was conducted at 42°C, and the motility zone was measured after 24 h of incubation. For the adhesion assay, monolayers of primary chicken enterocytes (∼105 cells/well) were inoculated with C. jejuni (6 log cfu/well) either in the presence or absence of carvacrol, and the adhered C. jejuni were enumerated after 90 min of incubation at 42°C. The effect of carvacrol on C. jejuni quorum sensing and susceptibility to acid/bile stress was investigated using a bioluminescence assay and an acid–bile survival assay, respectively. The SIC (0.002%) of carvacrol reduced the motility of C. jejuni strains S-8 and NCTC 81-176 by ∼50 and 35%, respectively (P

Campylobacter jejuni is the leading cause of human foodborne illness globally, and is strongly linked with the consumption of contaminated poultry products. Several studies have shown that C. jejuni can form sanitizer tolerant biofilm leading to product contamination, however, limited research has been conducted to develop effective control strategies against C. jejuni biofilms. This study investigated the efficacy of three generally recognized as safe status phytochemicals namely, trans-cinnamaldehyde (TC), eugenol (EG), or carvacrol (CR) in inhibiting C. jejuni biofilm formation and inactivating mature biofilm on common food contact surfaces at 20 and 37°C. In addition, the effect of phytochemicals on biofilm architecture and expression of genes and proteins essential for biofilm formation was evaluated. For the inhibition study, C. jejuni was allowed to form biofilms either in the presence or absence of sub-inhibitory concentrations of TC (0.75 mM), EG (0.61 mM), or CR (0.13 mM) for 48 h and the biofilm formation was quantified at 24-h interval. For the inactivation study, C. jejuni biofilms developed at 20 or 37°C for 48 h were exposed to the phytochemicals for 1, 5, or 10 min and surviving C. jejuni in the biofilm were enumerated. All phytochemicals reduced C. jejuni biofilm formation as well as inactivated mature biofilm on polystyrene and steel surface at both temperatures (P < 0.05). The highest dose of TC (75.64 mM), EG (60.9 mM) and CR (66.56 mM) inactivated (>7 log reduction) biofilm developed on steel (20°C) within 5 min. The genes encoding for motility systems (flaA, flaB, and flgA) were downregulated by all phytochemicals (P < 0.05). The expression of stress response (cosR, ahpC) and cell surface modifying genes (waaF) was reduced by EG. LC-MS/MS based proteomic analysis revealed that TC, EG, and CR significantly downregulated the expression of NapA protein required for oxidative stress response. The expression of chaperone protein DnaK and bacterioferritin required for biofilm formation was reduced by TC and CR. Scanning electron microscopy revealed disruption of biofilm architecture and loss of extracellular polymeric substances after treatment. Results suggest that TC, EG, and CR could be used as a natural disinfectant for controlling C. jejuni biofilms in processing areas.

Campylobacter jejuni, a leading cause of foodborne disease in humans, associate primarily with consumption of contaminated poultry and poultry products. Intervention strategies aimed at reducing C. jejuni contamination on poultry products could significantly reduce C. jejuni infection in humans. This study evaluated the efficacy of gum arabic (GA) and chitosan (CH) fortified with carvacrol (CR) as an antimicrobial coating treatment for reducing C. jejuni on chicken wingettes. Aforementioned compounds are generally recognized as safe status compounds obtained from gum arabic tree, crustaceans and oregano oil respectively. A total of four separate trials were conducted in which wingettes were randomly assigned to baseline, saline control (wingettes washed with saline), GA (10%), CH (2%), CR (0.25, 0.5, or 1%) or their combinations. Each wingette was inoculated with a cocktail of four wild-type strains of C. jejuni (∼7.5 log10 cfu/sample). Following 1 min of coating in aforementioned treatments, wingettes were air dried (1 h) and sampled at 0, 1, 3, 5, and 7 days of refrigerated storage for C. jejuni and total aerobic counts (n = 5 wingettes/treatment/day). In addition, the effect of treatments on wingette color was measured using a Minolta colorimeter. Furthermore, the effect of treatments on the expression of C. jejuni survival/virulence genes was evaluated using real-time quantitative PCR. Results showed that all three doses of CR, CH or GA-based coating fortified with CR reduced C. jejuni from day 0 through 7 by up to 3.0 log10 cfu/sample (P < 0.05). The antimicrobial efficacy of GA was improved by CR and the coatings reduced C. jejuni by ∼1 to 2 log10 cfu/sample at day 7. Moreover, CH + CR coatings reduced total aerobic counts when compared with non-coated samples for a majority of the storage times. No significant difference in the color of chicken wingettes was observed between treatments. Exposure of pathogen to sublethal concentrations of CR, CH or combination significantly modulated select genes encoding for energy taxis (cetB), motility (motA), binding (cadF), and attachment (jlpA). The results suggest that GA or CH-based coating with CR could potentially be used as a natural antimicrobial to control C. jejuni in postharvest poultry products.

Chickens provided with outdoor access often do not fully use the range area. Natural cover, such as trees, can provide shelter and increase range use, but may not be practical for use in all free-range operations. A study was conducted to determine whether constructed enrichments that simulate natural structures increase range use and impact behavior of meat chickens. Slow-growing Delaware chickens were raised in floor pens (17 birds/pen) in a naturally ventilated house, with a pophole in each pen that allowed daily access to a vegetation-covered outdoor area. Feed and water were provided inside and outside. Birds were randomly assigned to one of 2 treatments: no range enrichment (control; NON) or range enrichment (ENR), which had roosts made of plastic pipe or screened shelters placed 7.6 m and 22.9 m from the house and overhead shade panels at 15.2 m. There were 4 replications. The numbers of birds inside and in the 4 quadrants of the range were counted in 7-min intervals 3 times daily (0900 h, 1300 h, and 1600 h) for 3 consecutive d when the birds were 7 and 10 wk of age; the numbers of birds performing various behaviors also were counted. On average, only 12.9% of birds used the range at any given time. The behavior of the birds was strongly affected by location (inside vs. outside), with birds mainly foraging and walking while outside and feeding, standing, and sitting while inside. Time of d impacted the number of birds that ranged (P ≤ 0.0001), with fewest birds outside during mid-day. Overall, birds using the range were most often (71%) observed in the quadrant nearest the house (zero to 7.6 m). However, in the ENR treatment, more birds (13%; P ≤ 0.0001) were observed in the farthest 2 quadrants (15.2 to 30.5 m from the house) than in the NON treatment (6%). This indicates that adding constructed enrichments to the range encouraged meat chickens to use it more fully.

SUMMARY In alternative poultry production, such as free-range and organic, alternative feeding methods may be useful. Instead of a single fully Formulated diet, a “Choice” method offers 2 complementary feeds, a protein concentrate and a grain, between which birds self-select. This method was used in the past and may allow free-range birds that encounter diverse environmental conditions to adjust their diets to meet changing nutritional needs. A trial was conducted to study the impact of Choice feeding organic meat chickens vs. Formulated feeding. Chicks were raised to 64 d in an organic research facility with outdoor access. Birds in the Choice treatment were offered cracked corn and, separately, a concentrate composed of roasted soybeans, fishmeal, and mineral and vitamin premix. During the trial, Choice birds self-selected a diet that was low in protein (only 12% CP during the last week of production). Live weight gains, as well as carcass and breast weights, were lower for birds in the Choice treatment compared to the Formulated treatment; however, FCR was superior for Choice and yields did not differ. The cost of Choice feed was lower than Formulated ($0.58/kg vs. $0.66/kg, respectively). Results indicate that Choice feeding may be useful in alternative and free-range poultry production, especially in organic production. It enables the use of farm-raised feeds, important for on-farm nutrient cycling and reducing the cost of expensive organic feed.

Campylobacter jejuni, a major cause of human gastroenteritis worldwide, is often associated with the consumption of contaminated poultry products. With increasing consumer preference to natural and minimally processed foods, interventions utilizing natural antimicrobials for controlling C. jejuni on poultry products are gaining popularity. This study investigated the efficacy of the generally recognized as safe compound carvacrol (CR) as a wash treatment in reducing C. jejuni and aerobic bacteria on chicken skin. Two separate studies, each with 2 trials, were conducted. In the first study, the efficacy of CR suspension (0, 0.25, 0.5, 1, and 2%) was investigated, whereas in the second the efficacy of CR as suspension, emulsion, and nanoemulsion was studied. In both studies, skin samples were inoculated with 50 μL (∼8 log10 cfu/sample) of a cocktail of 4 wild strains of C. jejuni. After 30 min of attachment, samples were washed with the respective treatments for 1 min, drip dried for 2 min, and processed at 0, 8, 24, h post-treatment for enumeration of C. jejuni and aerobic bacterial counts (n = 5/treatment/time point). In addition, the effect of treatments on the color of chicken skin was evaluated. Data were analyzed using PROC MIXED procedure of SAS. In the first study, all the tested doses of CR suspension consistently reduced C. jejuni counts across all time points. The 2% CR suspension wash reduced C. jejuni counts by ∼2.4 to 4 log10 cfu/sample (P0.05). In addition, 1% and 2% CR suspensions significantly reduced aerobic counts at all the time points. The results from the second study suggest that anti-Campylobacter efficacy of CR emulsion or nanoemulsion treatments was not improved compared to CR suspension. Several CR suspension treatments were more effective than corresponding emulsion or nanoemulsion treatments. No significant differences were observed in the color of the samples between treatments (P0.05). The results suggest that CR could potentially be used as an antimicrobial wash treatment in postharvest poultry.

Campylobacter jejuni infection in humans is strongly associated with the consumption of contaminated poultry products. With increasing consumer demand for minimally processed and natural product, there is a need for novel intervention strategies for controlling C. jejuni. Antimicrobial coatings are increasingly being used for preventing food contamination due to their efficacy and continuous protection of product. This study investigated the efficacy of pectin and chitosan coating fortified with eugenol to reduce C. jejuni on chicken wingettes. Pectin, chitosan, and eugenol are generally recognized as safe status compounds derived from berries, crustaceans, and cloves respectively. Each wingette was inoculated with a mixture of 4 wild-type strains of C. jejuni (approximately 107 CFU/sample) and randomly assigned to controls, pectin (3%), chitosan (2%), eugenol (0.5, 1, or 2%), or their combinations. Following 1 min of coating, wingettes were air-dried, vacuum sealed, and sampled on 0, 1, 3, 5, and 7 d of refrigerated storage for C. jejuni and aerobic counts (n = 5 wingettes/treatment/d). In addition, the effect of treatments on wingette color and expression of C. jejuni survival/virulence genes was evaluated. All 3 doses of eugenol or chitosan significantly reduced C. jejuni and aerobic bacteria from 0 d through 7 d. Incorporation of 2% eugenol in chitosan improved coating efficiency and reduced C. jejuni counts by approximately 3 Log CFU/sample at the end of 7 d of storage (P < 0.05). Similarly, the antimicrobial efficacy of pectin was improved by 2% eugenol and the coating reduced C. jejuni by approximately 2 Log CFU/sample at 7 d of storage. Chitosan coating with 2% eugenol also showed greater reductions of total aerobic counts as compared to individual treatments of eugenol and chitosan. No significant difference in the color of chicken wingettes was observed between treatments. Exposure of C. jejuni to eugenol, chitosan, or combination significantly modulated select genes encoding for motility, quorum sensing, and stress response. Results demonstrate the potential of pectin or chitosan coating fortified with eugenol as a postharvest intervention against C. jejuni contamination on poultry products.

Campylobacter is one of the leading causes of foodborne illness worldwide and is associated with consumption of poultry products. One potential strategy to reduce Campylobacter colonization in poultry is the use of probiotics. In an attempt to reduce Campylobacter in poultry, we isolated 117 GRAS (generally recognized as safe) bacterial isolates from the ceca of healthy birds and evaluated their efficacy against Campylobacter, using a soft agar overlay technique. Twenty-six isolates (Bacillus and Lactobacillus spp.) with greatest ability to inhibit Campylobacter in vitro, were tested in birds. In these studies, bacterial isolates were administered orally on day-of-hatch and, chicks were challenged with a four-strain mixture of wild type C. jejuni (∼106 CFU/mL) on day 7. Cecal samples were collected on day 14 for Campylobacter enumeration. Out of 26 isolates, 3 isolates demonstrated a reduction in Campylobacter counts (1 to 2 logs). In an attempt to improve the efficacy of these 3 isolates, follow-up studies were conducted with various doses of 2 prebiotics (fructooligosaccharide [FOS] or mannan oligosaccharide [MOS]) in the feed. Campylobacter counts were not reduced for any of the FOS treatments (0.125%, 0.25%, or 0.5%) or the MOS treatments (0.04%, 0.08%, or 0.16%), but were reduced for the combination of isolate 3 with 0.04% MOS in feed. The results of this study indicate that the selection and administration of bacterial isolates in combination with selected prebiotics may reduce enteric Campylobacter counts in preharvest poultry.

Heat stress (HS) adversely affects growth performance and inflicts heavy economic losses to the poultry industry. There is, therefore, a critical need to identify new alternative strategies to alleviate the negative effects induced by HS. The tropic medicinal plant, Morinda citrifolia (Noni), is being used in livestock nutrition, however the literature is limited and conflicting for its impact on growth performance. The present study aimed to determine the effect of Noni on feeding and drinking behavior as well as on the hypothalamic expression of stress- and metabolic-related genes in broiler chickens exposed to acute HS. A total of 480 1 day-old male broiler chicks were randomly assigned to 12 controlled environmental chambers. Birds were subjected to two environmental conditions (TN, 25°C vs. HS, 35°C for 2 h) and fed two diets (control vs. 0.2% Noni) in a 2 × 2 factorial design. Feed intake and core body temperature (BT) were recorded during HS period. Blood was collected and hypothalamic tissues were harvested for target gene and protein analyses. Acute HS-broilers exhibited higher BT (~1°C), spent less time eating with a significant decrease in feed intake, and spent more time drinking along with higher drinking frequency compared to those maintained under TN conditions. Although Noni supplementation did not improve feed intake, it significantly delayed (~30 min) and reduced the BT-induced by HS. At molecular levels and under HS conditions, Noni supplementation down regulated the hypothalamic expression of HSP90 and its related transcription factors HSF1, 2, and 4, increased orexin mRNA levels, and decreased the phosphorylation levels of AMPKα1/2Thr172 and mTORSer2481. Together, these data indicated that Noni supplementation might modulate HS response in broilers through central orexin-AMPK-mTOR pathways.

Heat stress (HS) has been reported to alter fat deposition in broilers, however the underlying molecular mechanisms are not well-defined. The objectives of the current study were, therefore: (1) to determine the effects of acute (2 h) and chronic (3 weeks) HS on the expression of key molecular signatures involved in hepatic lipogenic and lipolytic programs, and (2) to assess if diet supplementation with dried Noni medicinal plant (0.2% of the diet) modulates these effects. Broilers (480 males, 1 d) were randomly assigned to 12 environmental chambers, subjected to two environmental conditions (heat stress, HS, 35°C vs. thermoneutral condition, TN, 24°C) and fed two diets (control vs. Noni) in a 2 × 2 factorial design. Feed intake and body weights were recorded, and blood and liver samples were collected at 2 h and 3 weeks post-heat exposure. HS depressed feed intake, reduced body weight, and up regulated the hepatic expression of heat shock protein HSP60, HSP70, HSP90 as well as key lipogenic proteins (fatty acid synthase, FASN; acetyl co-A carboxylase alpha, ACCα and ATP citrate lyase, ACLY). HS down regulated the hepatic expression of lipoprotein lipase (LPL) and hepatic triacylglycerol lipase (LIPC), but up-regulated ATGL. Although it did not affect growth performance, Noni supplementation regulated the hepatic expression of lipogenic proteins in a time- and gene-specific manner. Prior to HS, Noni increased ACLY and FASN in the acute and chronic experimental conditions, respectively. During acute HS, Noni increased ACCα, but reduced FASN and ACLY expression. Under chronic HS, Noni up regulated ACCα and FASN but it down regulated ACLY. In vitro studies, using chicken hepatocyte cell lines, showed that HS down-regulated the expression of ACCα, FASN, and ACLY. Treatment with quercetin, one bioactive ingredient in Noni, up-regulated the expression of ACCα, FASN, and ACLY under TN conditions, but it appeared to down-regulate ACCα and increase ACLY levels under HS exposure. In conclusion, our findings indicate that HS induces hepatic lipogenesis in chickens and this effect is probably mediated via HSPs. The modulation of hepatic HSP expression suggest also that Noni might be involved in modulating the stress response in chicken liver.

Background:Salmonella Enteritidis phage type 8 (PT8) is a major poultry-associated Salmonella strain implicated in foodborne outbreaks in the United States. We previously reported that two plant-derived compounds generally recognized as safe (GRAS), trans-cinnamaldehyde (TC), and eugenol (EG), significantly reduced S. Enteritidis colonization in broiler and layer chickens. To elucidate potential PT8 genes affected by TC and EG during colonization, a whole-genome microarray analysis of the bacterium treated with TC and EG was conducted.Results:S. Enteritidis PT8 was grown in Luria-Bertani broth at 37°C to an OD600 of ~0.5. Subinhibitory concentrations (SICs; concentration that does not inhibit bacterial growth) of TC (0.01%; 0.75 mM) or EG (0.04%; 2.46 mM) were then added to the culture. S. Enteritidis PT8 RNA was extracted before and 30 min after TC or EG addition. Labeled cDNA from three replicate experiments was subsequently hybridized to a microarray of over 99% of S. Enteritidis PT4 genes, and the hybridization signals were quantified. The plant-derived compounds down-regulated (P < 0.005) expression of S. Enteritidis PT8 genes involved in flagellar motility, regulation of the Salmonella Pathogenicity Island 1, and invasion of intestinal epithelial cells. TC and EG also suppressed transcription of genes encoding multiple transport systems and outer membrane proteins. Moreover, several metabolic and biosynthetic pathways in the pathogen were down-regulated during exposure to the plant-derived compounds. Both TC and EG stimulated the transcription of heat shock genes, such as dnaK, dnaJ, ibpB, and ibpA in S. Enteritidis PT8 (P < 0.005). The results obtained from microarray were validated using a quantitative real-time PCR.Conclusion: The plant-derived compounds TC and EG exert antimicrobial effects on S. Enteritidis PT8 by affecting multiple genes, including those associated with virulence, colonization, cell membrane composition, and transport systems.

Human Campylobacter infections, a leading foodborne illness globally, has been linked with the high prevalence of this bacterium on raw retail chicken products. Reduction of Campylobacter counts on poultry products would greatly reduce the risk of subsequent infections in humans. To this end, this study investigated the potential of the phytophenolic compound β-resorcylic acid (BR) to reduce Campylobacter counts on postharvest poultry (chicken skin or meat). Four trials in total, two each on thigh skin or breast meat, were conducted in which chicken skin or meat samples (2 ± 0.1 g; 10 samples per treatment) were inoculated with 50 μL (∼106 CFU per sample) of a cocktail of four wild strains of C. jejuni. After 30 min of attachment, inoculated samples were dipped in a 0, 0.5, 1, or 2% BR solution for 30 s immediately followed by vigorously vortexing the samples in Butterfield's phosphate diluent and plating the supernatant for Campylobacter enumeration. In addition, the effect of BR on the color of skin and meat samples was studied. Moreover, the change in the expression of survival and virulence genes of C. jejuni exposed to BR was evaluated. Data were analyzed by the PROC MIXED procedure of SAS (P 0.05). Real-time PCR results revealed that BR treatment down-regulated expression of select genes coding for motility (motA, motB) and attachment (cadF, ciaB) in the majority of C. jejuni strains. Stress response genes (sodB, katA) were upregulated in C. jejuni S-8 (P < 0.05). Overall, our results suggest that BR could be effectively used as antimicrobial dip treatment during poultry processing for reducing Campylobacter on chicken carcasses.

Campylobacter is one of the major foodborne pathogens that result in severe gastroenteritis in humans, primarily through consumption of contaminated poultry products. Chickens are the reservoir host of Campylobacter, where the pathogen colonizes the ceca, thereby leading to contamination of carcass during slaughter. A reduction in cecal colonization by Campylobacter would directly translate into reduced product contamination and risk of human infections. With increasing consumer demand for antibiotic free chickens, significant research is being conducted to discover natural, safe and economical antimicrobials that can effectively control Campylobacter colonization in birds. This study investigated the efficacy of in-feed supplementation of a phytophenolic compound, β-resorcylic acid (BR) for reducing Campylobacter colonization in broiler chickens. In two separate, replicate trials, day-old-chicks (Cobb500; n = 10 birds/treatment) were fed with BR (0, 0.25, 0.5, or 1%) in feed for a period of 14 days (n = 40/trial). Birds were challenged with a four-strain mixture of Campylobacter jejuni (∼106 CFU/ml; 250 μl/bird) on day 7 and cecal samples were collected on day 14 for enumerating surviving Campylobacter in cecal contents. In addition, the effect of BR on the critical colonization factors of Campylobacter (motility, epithelial cell attachment) was studied using phenotypic assay, cell culture, and real-time quantitative PCR. Supplementation of BR in poultry feed for 14 days at 0.5 and 1% reduced Campylobacter populations in cecal contents by ∼2.5 and 1.7 Log CFU/g, respectively (P < 0.05). No significant differences in feed intake and body weight gain were observed between control and treatment birds fed the compound (P > 0.05). Follow up mechanistic analysis revealed that sub-inhibitory concentration of BR significantly reduced Campylobacter motility, attachment to and invasion of Caco-2 cells. In addition, the expression of C. jejuni genes coding for motility (motA, motB, fliA) and attachment (jlpA, ciaB) was down-regulated as compared to controls (P < 0.05). These results suggest that BR could potentially be used as a feed additive to reduce Campylobacter colonization in broilers.

Campylobacter is a leading worldwide cause of foodborne illness associated with consumption of poultry products. Unfortunately, most preharvest treatments fail to reduce this enteric foodborne pathogen in poultry. The efficacy of natural plant extracts, such as thymol and carvacrol, has efficacy against other enteric pathogens but has not been evaluated against Campylobacter. To accomplish this, day old broiler chicks (n = 10 chicks/dose) were fed 0% (controls) or thymol or carvacrol or combinations of these compounds in feed in four different trials. Birds were orally challenged with Campylobacter jejuni at day 3 and at day 10, cecal samples were collected for Campylobacter enumeration. Campylobacter counts were reduced for 0.25% thymol (trial 1), 1% carvacrol or 2% thymol (trial 2) treatments, or a combination of both thymol and carvacrol at 0.5% (trial 3) in this study (P

Outdoor access is an important part of organic and free-range poultry production, yet limited information exists on the effect of various housing and production systems on growth performance and colonization of food-borne pathogens. Therefore, the primary purpose of the current study was to evaluate the influence of different housing systems, particularly fixed versus small, portable houses, with and without outdoor access to pasture, on seasonal growth performance, leg quality, and presence of bacterial food-borne pathogens. In the current study, we used fast-growing broilers, as many small producers use commercial broilers due to their carcass conformation and high breast yield compared with slow-growing hybrids or standard heritage breeds. Although interest in alternative genetics exists because they may be more adapted to outdoor production, they require longer growing periods, with accompanying labor and cost. A pasture containing a mixture of forages was used to simulate the conditions common for small farms in the local region. The experiment had 4 treatment groups: (1) small, portable hoop houses with access to pasture, (2) small, portable hoop houses without access to pasture, (3) a fixed house with access to the outdoors, and (4) a fixed house without access to the outdoors. The present study was repeated at different times of the year to determine if a seasonal effect on the consumption of pasture and carcass quality was present. Overall, raising birds in hoop houses resulted in a reduced growth rate compared with birds raised in the fixed house. None of the production systems altered bone strength or feed conversion. Food-borne pathogens commonly associated with poultry were not found in any of the environments tested. Seasonal production was an issue in the small hoop house birds, as extreme heat in the summer resulted in early termination of that trial. Expanding on forage choice in pastures and customizing hoop houses to deal with weather fluctuations, especially in regions where extreme heat may affect production, are important considerations for these systems.

To evaluate potential bacterial runoff from poultry litter, litter was applied to test plots and exposed to simulated rainfall 1, 8 or 15 d after litter application. Runoff samples were tested for Salmonella and Campylobacter, two bacterial pathogens commonly associated with poultry, as well as common fecal indicators such as coliforms, enterococci and Escherichia coli. The runoff samples were evaluated from treatments of no litter (control), or the equivalent of 1, 2 or 4 ton/acre of untreated poultry litter. Additionally, runoff samples from treatments of 2 tons/acre of alum-treated litter, 2 tons/acre composted litter and 2 ton/acre deep-stacked litter were compared for bacterial content. Three replicates of the treatments were performed, for a total of 21 test plots. No Campylobacter was isolated from any of the samples and the majority of samples tested negative for Salmonella. Although Salmonella was detected in runoff from many of the plots, it may have originated from sources other than the applied litter (rodents, birds, etc.) since it was detected in two of the unfertilized control plots.

SUMMARY Interest in small- and medium-scale free-range poultry production for local and regional markets is growing, and alternative feeding methods should be considered. Free-choice feeding is a method that offers birds separate feedstuffs, such as grains, protein concentrates, and natural vitamin and mineral sources, from which they can self-select a diet suited to their changing needs. Free-choice feeding may prove useful in production systems with outdoor access because nutrient needs change widely due to temperature fluctuations and bird activity. Many small producers do not have access to the nutritional services that large producers do and may have specific goals in regard to nutrition, such as using farm-raised feed ingredients and pasture forage to provide nutrients. In addition, most organic programs do not permit the use of synthetic amino acids in feed. Free-choice methods have been used historically and can be useful for alternative producers, making use of farm-raised feeds to improve savings and increase nutrient cycling. In the current study, a fully formulated diet and free-choice diet were compared in a free-range system using slow-growing meat chickens. The formulated diet was a commercial product (20% CP), whereas the free-choice diet chosen by birds was much lower in CP (13%). Final live weights did not differ between treatments; however, ready-to-cook yield and breast yields were higher in the birds from the formulated treatment, most likely due to amino acid supplements in the formulated feed. The diet chosen by free-choice birds was less expensive than the formulated diet.

Previous studies conducted in our laboratory have demonstrated that intestinal barrier function can be adversely affected by diet ingredients or feed restriction, resulting in increased intestinal inflammation-associated permeability. Two experiments were conducted in broilers to evaluate the effect of three concentrations of Aflatoxin B1 (AFB1; 2, 1.5, or 1 ppm) on gastrointestinal leakage and liver bacterial translocation (BT). In experiment 1, 240 day-of-hatch male broilers were allocated in two groups, each group had six replicates of 20 chickens (n = 120/group): Control feed or feed + 2 ppm AFB1. In experiment 2, 240 day-of-hatch male broilers were allocated in three groups, each group had five replicates of 16 chickens (n = 80/group): Control feed; feed + 1 ppm AFB1; or feed + 1.5 ppm AFB1. In both experiments, chickens were fed starter (days 1–7) and grower diets (days 8–21) ad libitum and performance parameters were evaluated every week. At day 21, all chicks received an oral gavage dose of FITC-d (4.16 mg/kg) 2.5 h before collecting blood samples to evaluate gastrointestinal leakage of FITC-d. In experiment 2, a hematologic analysis was also performed. Liver sections were aseptically collected and cultured using TSA plates to determine BT. Cecal contents were collected to determine total colony-forming units per gram of Gram-negative bacteria, lactic acid bacteria (LAB), or anaerobes by plating on selective media. In experiment 2, liver, spleen, and bursa of Fabricius were removed to determine organ weight ratio, and also intestinal samples were obtained for morphometric analysis. Performance parameters, organ weight ratio, and morphometric measurements were significantly different between Control and AFB1 groups in both experiments. Gut leakage of FITC-d was not affected by the three concentrations of AFB1 evaluated (P > 0.05). Interestingly, a significant reduction in BT was observed in chickens that received 2 and 1 ppm AFB1. An increase (P

Eggshells are significant part of hatchery waste which consist of calcium carbonate crust, membranes, and proteins and peptides of embryonic origins along with other entrapped contaminants including microbes. We hypothesized that using this product as a nutritional additive in poultry diet may confer better immunity to the chickens in the paradigm of mammalian milk that enhances immunity. Therefore, we investigated the effect of hatchery eggshell membranes (HESM) as a short term feed supplement on growth performance and immunity of chickens under bacterial lipopolysaccharide (LPS) challenged condition. Three studies were conducted to find the effect of HESM supplement on post hatch chickens. In the first study, the chickens were fed either a control diet or diets containing 0.5% whey protein or HESM as supplement and evaluated at 5 weeks of age using growth, hematology, clinical chemistry, plasma immunoglobulins, and corticosterone as variables. The second and third studies were done to compare the effects of LPS on control and HESM fed birds at 5 weeks of age following at 4 and 24 h of treatment where the HESM was also sterilized with ethanol to deplete bacterial factors. HESM supplement caused weight gain in 2 experiments and decreased blood corticosterone concentrations. While LPS caused a significant loss in body weight at 24 h following its administration, the HESM supplemented birds showed significantly less body weight loss compared with the control fed birds. The WBC, heterophil/lymphocyte ratio, and the levels of IgG were low in chickens fed diets with HESM supplement compared with control diet group. LPS challenge increased the expression of pro-inflammatory cytokine gene IL-6 but the HESM fed birds showed its effect curtailed, also, which also, favored the up-regulation of anti-inflammatory genes compared with control diet fed chickens. Post hatch supplementation of HESM appears to improve performance, modulate immunity, and increase resistance of chickens to endotoxin.

SUMMARY As parasites become resistant to available anthelmintics, new methods of control are needed. New drugs take a long time to develop in addition to being expensive; therefore, there is increasing interest in finding and using natural alternatives. Additionally, natural remedies are needed for the organic sector because synthetic drugs are not allowed and birds with outdoor access are likely to encounter parasites. Sericea lespedeza [SL; Lespedeza cuneata (Dum. Cours.) G. Don.] is a common perennial legume found in pastures across the southern United States that has been shown to be effective at controlling parasitic nematodes in small ruminants because of its condensed tannin content. Diets high in condensed tannins are often unpalatable to poultry; however, growers report that chickens maintained on pastures will consume SL. These reports and the level of consumption have not been verified. Therefore, before determining its potential in controlling parasites in poultry, we confirmed in a preliminary study that birds on pasture consumed SL (92% of birds examined had SL in crops), and in a subsequent study, dried SL leaves were added to a commercial broiler feed to determine the palatability of SL at various concentrations. Diets included 0 (control), 5, 10, or 20% SL (DM weight) and were fed from hatch until slaughter at 6 wk of age. Male broilers (n = 80) were randomly divided into 8 groups and fed 1 of the 4 diets in replicate. Body weight gains were similar between the control and SL at 5%. Including more than 5% SL in the diet reduced individual BW (P < 0.05). At the end of the feeding period, the digestive organs as a percentage of body weight of birds fed 20% SL were larger than those of control birds. Feed conversion was higher in the 20% SL treatment (2.31) than in the control treatment (1.63; P < 0.05). Palatability of SL did not appear to be a problem because all treatment groups consumed a similar amount of feed. Therefore, the effects of SL on parasite control will be evaluated in subsequent studies.

SUMMARY In this study, we investigated the therapeutic efficacy of the plant compounds trans-cinnamaldehyde (TC) and eugenol (EG) on reducing Salmonella enterica serovar Enteritidis (SE) in commercial, market-age broiler chickens. Straight run, day-old commercial broiler chicks (N = 84) were randomly grouped into 6 groups of 14 birds each (n = 14/group): a negative control (no SE, no TC or EG), EG control (no SE, 1% EG), TC control (no SE, 0.75% TC), a positive control (SE, no TC or EG), an EG challenge group (SE, 1% EG), and a TC challenge group (SE, 0.75% TC). Before the start of each experiment, the flock was screened for any inherent Salmonella (n = 12 birds/experiment). Birds were given ad libitum access to Salmonella-free feed and water. On d 30, birds were challenged with a 4-strain mixture of SE (8 log10 cfu/bird). Two birds from each group were killed after 24 h (d 31) to check for colonization of SE in the cecum. Birds were given feed supplemented with TC (0.75%) or EG (1%) for 5 d before slaughter on d 42 (n = 10 birds/group) for determination of SE populations in the cecum and cloaca. The experiment was repeated 2 times. The trans-cinnamaldehyde and EG consistently reduced SE in the samples in both experiments (P 0.05). On the basis of histological analysis, no abnormal changes in the liver were observed because of supplementation of plant compounds. Therefore, TC and EG supplemented through the feed could reduce SE colonization in market-age chickens.

Campylobacter is one of the leading causes of bacterial human acute gastroenteritis. These microorganisms are highly prevalent in poultry semen and may contribute to vertical transmission of the pathogen between the breeder hen and offspring. Unfortunately, strategies to reduce or eliminate these pathogens in poultry semen negatively impact sperm viability. Many plant essential oils have been reported to exhibit antimicrobial activity against bacteria, fungi and viruses. The objective of our study was to examine the efficacy of trans-cinnamaldehyde, the main component in cinnamon oil, to reduce Campylobacter concentrations in chicken semen. Semen was collected from roosters, pooled and diluted with semen extender, then divided into treatments: negative control (no Campylobacter, no trans-cinnamaldehyde), positive control (inoculated with Campylobacter, no trans-cinnamaldehyde) or treatments containing concentrations of 0.24, 0.12, 0.06, 0.03 or 0.015% trans-cinnamaldehyde. Treatment groups receiving Campylobacter were then immediately inoculated with ~10 cfu/mL of a wild-type Campylobacter jejuni and 5 held at 4°C or 23°C for 2 h. Semen was stored at 4°C for an additional 24 h and assessed for Campylobacter concentrations and sperm viability at 2, 6 and 24 h utilizing SYBR 14/Propidium iodide live/dead stain and fluorescent microscopy. The study was replicated eight times. After 2h at 23°C a 2 log reduction in Campylobacter counts were observed in the 0.12 and 0.24% trans-cinnamaldehyde treatment groups compared to positive controls. In the 4°C treatments, no differences were observed between treatments and controls after 2 h. Samples evaluated after 24 h incubation in vitro at 4°C, showed significant reductions of Campylobacter counts in the 0.06, 0.03 or 0.015% trans-cinnamaldehyde treatments groups, while the 0.12 and 0.24% groups eliminated detectable Campylobacter counts. Sperm viability remained at 80% or above for all treatment groups. Trans-cinnamaldehyde reduced Campylobacter in semen, without detrimentally affecting sperm viability and might provide a practical solution to eliminate Campylobacter in poultry semen after in vitro storage.