There is a demand for novel pathogen mitigation strategies in antibiotic-free poultry production, which has triggered the development of various probiotic application methods. One application method is the in ovo (in egg) administration of probiotics on incubation day (d) d ) 18, where the unhatched chick consumes a probiotic before hatch and prior to being exposed to environmental pathogens. Therefore, the objective of this study was to evaluate the influence of in ovo L. animalis, B. licheniformis, , or L. animalis + B. licheniformis (10(6) 6 cfu/50 mL L each) administration on hatch performance (N = 21 egg flats/treatment, 30 eggs/flat), live performance (N = 12 pens/treatment), and d of hatch immuno-physiological parameters (N = 12 birds/treatment) among Ross 708 broiler chicks. Data were analyzed by 1-way ANOVA with significance established at P <= 0.05. All in ovo probiotic treatments had greater % hatch than the control treatment, and eggs in ovo-administered with B. licheniformis had lower % late dead and % culled-pipped eggs. However, all in ovo probiotic treatments had lower average chick weights compared to those of the HVT vaccine control group. At hatch, chicks administered with B. licheniformis or L. animalis + B. licheniformis had greater relative ceca weight and lower peripheral blood leukocyte levels compared to those belonging to the control group. There were no effects on live performance during the first 2 wk post-hatch. These results show that B. licheniformis and L. animalis are effective candidates for in ovo probiotic administration, but further investigations regarding immuno-physiological responses to in ovo B. licheniformis administration are necessary.

A previous companion study utilized a 2 GS (Fast Growing [FG] or High Yielding [HY]) x 2 FF (Crumbles [C] or Intact Pellets [IP]) x 3 FQ (Low, Medium, or High) factorial arrangement to determine their impact on broiler performance. The 2 FF, C or P, were fed in the starter diet (d 0-18) as one of 3 FQ: low-2,210 mm (C) or 40% intact pellets (IP), medium -3,010 mm (C) or 60% IP, and high-3388 mm (C) or 80% IP. From 0 to 18 d, feeding increased FQ improved overall BW and BWG. The current study determined the APSC from d 0 to 6 and d 0 to 18 among these GS, FF, and FQ. This study utilized a subsample of pens from the com-panion study. From d 0 to 6 and 0 to 18, HY GS had a higher APSC. At d 0 to 18, GS x FF interacted, demonstrating that APSC only differed between GS when pellets were fed, with HY consuming a larger size. A FF x FQ interaction on 0-6 and 0-18 d demonstrated that, regard-less of FF broilers fed high FQ, had larger APSC. For birds fed low and medium FQ as a C, APSC was larger, but smaller when fed as IP. Correlations were found showing that as APSC increased, d 0 to 6 BW, BW gain, and FCR improved; this also occured for d 0 to 18 FCR. Data suggest that APSC is dependent upon GS and FF presented; further research is needed to verify APS preference when provided ad libitum amounts of each particle size.

Digestible lysine (dLys) requirements in broilers is heavily researched due to lysine's importance in diet formulation, body protein accretion, and dietary protein cost. As such, when novel broiler strains are established, it is important to evaluate their dLys requirements. The current objective was to determine the dLys requirement of male Cobb MV pound Cobb 500 broilers from d 0 to 14 and evaluate the carryover effect (d 14-41) of feeding varying starter levels of dLys. Two basal diets were formulated (0.88% dLys and 1.44% dLys), then blended to create 6 intermediate dLys treatments (ranging from 0.96 to 1.36% dLys), creating a total of 8 dLys experimental diets. A control diet (treatment 9-1.28% dLys) was separately made to confirm blending techniques. Treatments were arranged as a randomized complete block design (RCBD) to 96 pens, with each pen having 14 male chicks. In general, increasing dLys resulted in improvements in performance metrics and processing weights. From d 0 to 14, feeding >= 1.20% dLys increased BW and BWG, feeding >= 0.96% dLys increased FI, with an exception in birds fed 1.44% dLys; stepwise reductions in FCR were observed as dLys increased from 0.88 until 1.20% dLys. Estimated dLys requirements ranged from 1.17 to 1.30% for BWG and 1.29 to 1.49% for FCR (using multiple regression methods). In general, carryover effect data (d 0-41) demonstrated that increasing starter dLys improved performance and d 42 processing. Future research should evaluate higher dLys levels than those used in this study and the dLys requirements of female Cobb MV pound Cobb 500 broilers during the starter phase.

This study was conducted to determine the effect of housing environment and laying hen strain on performance, egg quality, and microbiology of the cloaca and eggshell. A total of 1,152 Hy-Line Brown (HB) and Hy-Line W-36 White Leghorn (W-36) hens were used. All hens were kept in conventional cages (CC) from 18 to 32 wk of age and then moved to either enriched colony cages (EC) or free-range (FR) pens or continued in CC. Hens were randomly allocated into a 2 pound 3 factorial arrangement of 2 laying hen strains (brown and white) and 3 housing environments (CC, EC, and FR) in a split plot in time (hen age) design. The experiment was conducted from 32 to 85 wk of age. The experiment was divided into 2 phases: early phase (32 -51 wk of age) and late phase (52-85 wk of age). A 3 way interaction was observed for hen day egg production (HDEP) among housing environments, hen strain, and bird age in the early phase (P = 0.004) as well as in the late phase (P < 0.0001). In both of the phases, HDEP was higher in CC and FR than in EC. Hy-Line W-36 hens raised in EC had the lowest HDEP compared to other treatments. A 3-way interaction was observed for feed intake (FI; P = 0.017) and feed conversion ratio (FCR) in the late phase (P < 0.0001). The lowest FI and highest FCR were observed in EC for W-36 hens. Free-range hens performed in-between for eggshell quality when compared to CC and EC while HB had better egg quality than W-36. Freerange hens had higher cloacal bacterial counts for aerobes, anaerobes, and coliforms than CC and EC. Higher eggshell bacterial contamination was observed in eggs from FR versus eggs from CC and EC. These results indicate that both housing environment and laying hen strain affect performance and egg quality as well as cloacal and eggshell microbiology. Further studies should be conducted to determine food safety and economic impacts when using different hen strains and housing environments.

As progress is made towards extending the production cycle of the modern laying hen beyond 60 weeks of age, it is vital to develop effective nutritional strategies to sustain egg production and maintain eggshell quality. A 20-week study was conducted to evaluate the effects of feeding various ratios of fine (FL) and coarse (CL) limestone continuously (conventional) or only in the afternoon (split) on egg production and egg quality. The experiment was designed as randomized complete blocks with split plots over hen age. A 2 x 4 factorial arrangement of two feed distribution regimens (conventional and split) and four ratios of fine and coarse limestone (35:65, 25:75,15:85, and 0:100 FL:CL, respectively) were studied. Eight feeding regimens were tested with 4 feeding regimens that received the same diet in the morning and afternoon and the other 4 feeding regimens that received a diet without limestone in the morning but 4 diets with all the added limestone in the afternoon. An interaction was observed between feeding regimens and age of birds for mean eggshell breaking strength (P = 0.044), indicating that the split feeding regimen maintains eggshell breaking strength compared to conventional feeding regimen. There was an interaction (P < 0.001) between limestone particle ratio and age for feed intake indicating that higher amount of feed is consumed when fine limestone is not added to the diet. The main effect of limestone ratio was observed for tibial breaking strength (TBS) (P = 0.026), where the birds fed 35FL:65CL or 25FL:75CL ratio diets had a greater TBS than 15FL:85CL and 0FL:100CL. Split feeding alone was not able to improve the eggshell breaking strength. Therefore, future research should focus on a combined strategy of improved genetics, nutrition, feeding regimen, and management strategy to maintain the eggshell quality in the late production phase.

Recent research has tried to maximize broiler chick health and performance by utilizing commercial in-feed probiotics to inoculate fertile hatching eggs, and thus expose birds earlier to beneficial bacteria. However, the in ovo inoculation of a specific serotype of Bacillus subtilis was detrimental for broiler hatchability. Therefore, the objective of this study was to determine if other B. subtilis serotypes negatively affect hatchability or if it is associated with a specific serotype. It was also of interest to determine if the B. subtilis serotype influence chick performance and intestinal microflora. On d18 of incubation, 1886 fertile broiler eggs were in ovo inoculated with the following treatments (T): T1 = Marek's vaccine (MV), T2 = MV + B. subtilis (ATCC 6051), T3 = MV + B. subtilis (ATCC 8473), and T4 = MV + B. subtilis (ATCC 9466). It should be noted that in a previous study, T2 was detrimental to hatchability. Inoculated eggs were transferred to 3 hatchers/T. At hatch, chicks were weighed, feather sexed, and hatch residue analysis was conducted. Male chicks were randomly assigned to 40 raised wire cage so that there were 10 birds/cage. On d 0, 7, 14, and 21 of the grow-out, chicks and feed were weighed to calculate performance data. On these days, the ileum and ceca were aseptically collected to enumerate total aerobes and coliforms. No differences were observed for percentage of mid dead embryos, cracked eggs, and cull chicks (P > 0.05). However, hatch of transfer was significantly reduced by T2 compared to T1, T3, and T4 (P < 0.001). T2 had significantly higher percentages of late dead embryos and pips when compared to the other treatments (P = 0.002 and P < 0.001, respectively). Chicks hatched from T2 were not vigorous and, thus, not used for the grow-out trial. No differences were observed for growth performance characteristics for any of the treatments (P > 0.05). For bacterial enumeration, the ileum had equal or fewer bacterial counts for T3 and T4 when compared to T1 on most sampling days, except on d21 where T4 had higher aerobic and coliform counts (P ≤ 0.0001). For the ceca, T3 and T4 had equal or fewer bacterial counts than T1 on every sampling day (P ≤ 0.0001). These data demonstrate that not all B. subtilis evaluated are detrimental to hatchability, but rather, serotype dependent. In addition, different B. subtilis serotypes can modify the intestinal microflora with potential to reduce pathogenic bacteria present in young broiler, without impacting overall performance.

Avian pathogenic Escherichia coli (APEC) causes colibacillosis in poultry, which has been traditionally controlled by the prophylactic in-feed supplementation of antibiotics. However, antibiotics are being removed from poultry diets owing to the emergence of multidrug-resistant (MDR) bacteria. Therefore, alternatives to control APEC are required. This study aimed to evaluate the effects of in ovo inoculation of probiotics on the incidence of APEC in broilers and evaluate the virulence and antimicrobial resistance properties of the APEC isolates. On embryonic day 18, 4 in ovo treatments (T) were applied: T1 (Marek's vaccine [MV]), T2 (MV and Lactobacillus animalis), T3 (MV and Lactobacillus reuteri), and T4 (MV and Lactobacillus rhamnosus). A total of 180 male broilers per treatment were randomly placed in 10 pens. The heart, liver, spleen, and yolk sac were collected on day 0, 14, 28, and 42. Presumptive E. coli isolates were confirmed by real-time PCR. The positive isolates were screened for the APEC-related genes (iroN, ompT, hlyF, iss, and iutA), and E. coli isolates containing one or more of these genes were identified as APEC-like strains. A total of 144 APEC-like isolates were isolated from 548 organ samples. No differences (P > 0.05) among treatments were observed for the incidence of APEC-like strains in all organs when averaged over sampling days. However, when averaged over treatments, the incidence in the heart, liver, and yolk sac was different among sampling days; a significant increase was observed in these organs on day 14 compared with day 0. Twenty-five antimicrobial resistance genes were evaluated for all APEC-like isolates, and 92.4% of the isolates carried at least one antimicrobial resistance gene. Thirty-seven isolates were then selected for antimicrobial susceptibility testing; MDR strains accounted for 37.8% of the isolates. In conclusion, the in ovo inoculation of a single probiotic strain did not confer protection against APEC strains in broilers. The high prevalence of MDR isolates indicates that further research on antibiotic alternatives is required to prevent APEC infections in broilers.

Previous research in our laboratory demonstrated that feeding broiler chicks crumbles of 2,200 to 3,736 µm improved starter performance, suggesting chicks may be able to consume larger particles, even pellets, earlier than perceived. The objective of the current study was to evaluate the effects of 0 to 18 d variations in feed form (FF; crumble or intact pellets [IP]) and feed quality (FQ; low, medium, high) on starter performance utilizing 2 different genetic strains (GS; high yielding [HY] or fast growing [FG]). Starter FF and FQ carryover effects were also examined by feeding common pelleted diets for the remainder of the grow-out phases and measuring d 62 performance and d 63 processing. Day 0 to 18 FF and FQ interacted, whereas birds fed crumbles had the highest BW and BWG, regardless of crumble FQ; birds fed IP achieved increased weights when FQ was highest, similar to birds fed crumbles. Examining the carryover effects, 0 to 32 d FCR was improved by providing high FQ crumbles (3,388 µm). Overall data (d 0–62) demonstrated no significant differences for measured performance variables. Interactive differences were found for d 63 breast yield (BY), dependent on the FF and FQ presented from d 0 to 18 for each GS. In particular, HY strains demonstrated improved BY if fed low FQ crumbles or high FQ IP, whereas FG broilers demonstrated similar yields, regardless of FF and FQ. These data suggest that the length of the grow out is important when determining which FQ and FF to present in the starter growth phase.

Previous studies have suggested the use of probiotics, as alternative to antibiotics, to enhance broiler performance. The administration of probiotics in feed has been widely explored; however, few studies have evaluated the in ovo inoculation of probiotics. Therefore, the objective was to evaluate the impact of in ovo inoculation of different concentrations of GalliPro Hatch (GH), an Enterococcus faecium–based probiotic, on hatchability, live performance, and gastrointestinal parameters. Ross x Ross 708 fertile eggs were incubated, and on day 18, injected with the following treatments: 1) 50 μL of Marek's vaccine (MV), 2) MV and 1.4 × 105 cfu GH/50 μL, 3) MV and 1.4 × 106 cfu GH/50 μL, 4) MV and 1.4 × 107 cfu GH/50 μL. On the day of hatch, chicks were weighed, feather sexed, and hatch residue was analyzed. Male birds (640) were randomly assigned to 40 floor pens. On day 0, 7, 14, and 21 of the grow-out phase, performance data were collected. One bird from each pen was used to obtain yolk weight and intestinal segment weight and length. Hatchability was not impacted by any GH treatment (P = 0.58). On day 0, yolk weight was lower for all treatments than for MV alone. On day 0 to 7, feed intake was lower for 105 and 107 GH; the feed conversion ratio (FCR) was lower for all treatments than for MV alone (P = 0.05; P = 0.01, respectively). From day 14 to 21, the 107 GH treatment had higher BW gain (P = 0.05). For day 0 to 21, 107 GH had a lower FCR than MV alone (P = 0.03). On day 0, all GH treatments resulted in heavier tissues and longer jejunum, ileum, and ceca lengths than MV alone (P < 0.05). Spleen weight was higher for 105 and 107 GH than for MV alone. In conclusion, GH does not impact hatchability, and some concentrations improved live performance through the first 21 d of the grow-out phase. These improvements could result from the increased yolk absorption and improved intestinal and spleen morphology seen in this study.

Previous research has shown that feeding high amino acid density (AAD) diets or increased AME improved broiler performance, though the relationship between AAD and AME on performance needs to be further explored. Therefore, the objective of this study was to evaluate the impact of feeding 2 AAD and 4 AME levels from day 0 to 14 on performance and yield of 42-day-old Cobb MV X Cobb 500 males. Starter diets were formulated to medium or high AAD (HAA), and very low (VLE), low (LE), medium (ME), or high (HE) AME. Common diets were provided from day 15 to 41. A 2 X 4 factorial arrangement of treatments was used, with day 0 BW considered as a covariant. On day 0 to 14, birds receiving HAA had the lowest feed conversion ratio (FCR) corrected and uncorrected for mortality (uFCR). Birds receiving VLE diets had the highest day 0 to 14 FCR when compared to birds fed other AME levels. Feeding LE diets resulted in higher day 0 to 14 FCR when compared to ME and HE diets. An AAD X AME interaction for day 0 to 14 total Lys intake/bird found that Lys intake/bird decreased when increasing dietary AME for HAA diets. An AAD X AME interaction was observed for day 0 to 28 uFCR whereas increasing starter AAD in diets formulated to ME and HE increased day 0 to 28 uFCR; no change was observed for VLE and LE diets. However, overall performance and processing was not affected by varying starter AAD and AME levels. Further research should investigate similar feeding strategies, but in other feeding phases.

Research using a commercial broiler house demonstrated physical/nutrient feed segregation as feed varying in percent pellets (PP) and manufacturing technique was augered throughout a feed line (FL); these factors impacted bird performance and uniformity. The current objective was to investigate feed flow and segregation of pellets and fines as a bin of feed is augered throughout a commercial feed system. Over 1.5 wk, feed manufactured at a commercial mill was delivered (n = 4) to an empty feed bin at a commercial broiler house; feeds averaged 84 PP. Within the house, there were 6 FL (feft and right for each front, middle, and back line) and on each FL, 3 feed pan locations (0, 25, and 50 m) from which samples were obtained. Augering time (AT; n = 9; 56 h) was represented by the 6.5-h period between sampling. A FL 3 feed pan location interaction demonstrated PP at 0 m was higher for the entire right FL; at 25 m, PP increased for all FL except for back FL; at 50 m, all PP decreased, with feed pan locations at right front and back FL decreasing by the greatest magnitude. For AT, there were slight fluctuations in PP from AT 1-7 and a stepwise increase occurred from AT 7-9; PP was highest at AT 9. Data demonstrate that PP can be affected by AT because of feed segregation within the feed bin. In addition, beginning PP and mechanical equipment variations among FL may have affected pellet attrition and ultimately physical segregation of feed.

The objective of this study was to determine if the adaptation at planktonic stage to subinhibitory concentrations (SIC) of sodium hypochlorite (NaOCl) could modulate the biofilm forming ability of five Listeria monocytogenes strains V7, Scott A, FSL-N1-227, FSL F6-154 and ATCC 19116 representing serotypes 1/2a, 4b and 4c. Biofilm formation by NaOCl nonadapted and adapted L. monocytogenes planktonic cells was measured in the presence or absence of SIC of NaOCl. The biofilm formation ability of NaOCl nonadapted and adapted L. monocyotgenes planktonic cells was reduced only in the presence of NaOCl (P < 0.05). Scanning electron microscopy revealed that the continuous exposure of NaOCl induced morphological changes in the L. monocytogenes biofilm structure and reduced its attachment to polystyrene surface. The qRT-PCR results also showed that the subinhibitory NaOCl reduced biofilm formation related gene expression such as motility and quorum sensing signals (P < 0.05). These findings indicate that subinhibitory NaOCl can reduce the ability of L. monocytogenes planktonic cells to form biofilms on polystyrene surface.

Salmonella is a poultry-borne pathogen that causes illness throughout the world. Consequently, it is critical to control Salmonella during the process of converting broilers to poultry meat. Sanitization of a poultry processing facility, including processing equipment, is a crucial control measure that is utilized by poultry integrators. However, prevalence of Salmonella on equipment after sanitization and its potential risk to food safety has not been evaluated thoroughly. Therefore, the objective of this study was to evaluate the persistence of Salmonella on poultry processing equipment before and following cleaning and sanitization procedure. A total of 15 locations within 6 commercial processing plants were sampled at 3 time points: (A) after processing; (B) after cleaning; and (C) after sanitization, on 3 separate visits for a total of 135 samples per plant. Salmonella-positive isolates were recovered from samples using the United States Department of Agriculture MLG 4.09 conventional method. Presumptive Salmonella colonies were subjected to biochemical tests for confirmation. Salmonella isolates recovered after sanitization were serotyped and tested for the presence of specific virulence genes. A completely randomized design with a 6 × 3 × 15 factorial arrangement was utilized to analyze the results for Salmonella prevalence between processing plants. Means were separated using Fishers protected least significant difference when P ≤ 0.05. For Salmonella prevalence between processing plants, differences (P < 0.0001) were observed in the 6 plants tested where the maximum and minimum prevalence was 29.6 and 7.4%, respectively. As expected, there was a difference (P < 0.0001) in the recovery of Salmonella because of sampling time. Salmonella prevalence at time A (36%) was significantly higher, whereas there was no difference between time B (12%) and C (9%). There was a location effect (P < 0.0001) for the prevalence of Salmonella with the head puller, picker, cropper, and scalder having a significantly higher prevalence when compared with several other locations. At sampling time C, a trend toward a difference (P = 0.0899) was observed for Salmonella prevalence between the 6 plants, whereas significant differences were observed because of location (P = 0.0031). Five prominent Salmonella enterica serovars were identified, including Kentucky, Schwarzengrund, Enteritidis, Liverpool, and Typhimurium with S. Kentucky being the most prevalent. PCR analysis of 8 Salmonella virulence genes showed that the invA, sipB, spiA, sseC, and fimA were detected in all isolates, whereas genes carried on plasmids and/or fimbriae varied remarkably among all isolates. This study established Salmonella prevalence and persistence in poultry processing facilities after antimicrobial application through sanitization procedures which could result in contamination of poultry carcasses and food safety risks because of poultry meat.

Replicated research has not identified the impact of augering feed on the pellet quality, feed segregation, and resulting bird performance; therefore, 2 experiments were conducted. Experiment 1 was conducted to determine the effects of pellet-to-fine ratios (P:F; 55:45 or 75:25) and liquid application method (LAM; mixer liquid application method [MLAM] or postpellet liquid application method [PPLAM] addition of fat and phytase) on feed segregation, after augering, throughout a commercial feed line. Samples for each augered diet were obtained at 0, 15, 30, 32, 44, and 58 m on the feed line. After augering, each diet was retained by a feed pan location (FPL) from 0 to 30 and 32 to 58 m for experiment 2, to determine the effects of P:F, segregation, and FPL on day 28 to 56 performance and day 57 processing. Augering PPLAM diets increased percent pellets vs. MLAM diets. An FPL X P:F interaction found decreased percent pellets when augering from 0 to 15 and 44 to 58 m; 55:45 P:F diets had no change from 15 to 44 m; 75:25 P:F diets fluctuated. An LAM X P:F X FPL interaction showed decreased day 28 to 42 BW gain (BWG) for the MLAM and 75:25 P:F diets across FPL vs. PPLAM and 75:25 P:F diets. In addition, an LAM X P:F X FPL interaction demonstrated that the PPLAM affected day 56 BW uniformity by the FPL. The 75:25 P:F diet improved the BWG, as well as carcass and total breast weight. These data verify physical and nutrient (phytase) segregation occurs during augering and subsequently affects performance; future research should examine the specific nutrient segregation due to augering and the resulting impact on bird performance.

Previous research in our laboratory has revealed that feeding crumbled diets with various levels of starter digestible Lys (dLys) and AME affects early feed conversion ratio (FCR) of Cobb MV X Cobb 500 broilers. However, overall performance was not affected, likely due to treatment application occurring in the starter phase. Therefore, the objective of this study was to evaluate a 3 dLys (1.00, 1.08, and 1.18%) X 4 AME (2,937, 3,028, 3,116, and 3,206 kcal/kg) factorial arrangement of pelleted grower diet treatments (Gdiets) and their impact on 42-day-old Cobb MV X Cobb 500 females. Significant dLys X AME interactions demonstrated a stepwise decrease in FCR (day 14-28 and 14-35) when dLys increased at 2,937, 3,116, and 3,206 kcal/kg but not at 3,028 kcal/kg AME. A significant dLys X AME interaction was also observed for day 14-28 total Lys intake/bird. Overall data exhibited improvements in BW and BW gain (BWG) when feeding Gdiets of 1.08 or 1.18% dLys. Feeding Gdiets of 1.18% dLys or >= 3,028 kcal/kg AME optimized day 14-41 FCR. Processing data demonstrated improved breast yield when feeding Gdiets formulated to .1.08% dLys or formulated to 2,937 or 3,028 kcal/kg AME. The most profitable Gdiet was 1.18% dLys 13,028 kcal/kg AME. To determine the best feeding regime for this new cross, future research should evaluate the effects of varying dLys and AME levels during the finisher phase on broiler performance.

Recent research in our laboratory demonstrated that average particle size of feed from 0 to 14 d influenced overall (0 to 46 d) performance. However, optimal starter average feed particle size has not been identified and represents an important void, as this is a critical stage in a broiler's lifecycle. Therefore, 2 experiments were conducted to evaluate the effects of average particle size on 0 to 14 d broiler performance in an effort to determine the optimal average particle size. Both experiments utilized Ross × Ross 708 male broiler chicks that were provided diets varying in average feed particle size from 1,202 to 2,172 μm (Experiment 1) or 1,174 to 3,736 μm (Experiment 2). Performance variables were analyzed with a randomized complete block design using one-way ANOVA. Improvements were most apparent for FCR with an associated 0.03 improvement in both experiments when broilers were provided feed of 1,760 or 2,172 μm (Experiment 1) or larger than 2,257 μm, compared to those receiving smaller average feed particle sizes (Experiment 2). Additionally, a 30 g improvement for ending BW and BW gain was demonstrated in Experiment 2 for broilers receiving ≥2,800 μm. However, linear relationships for 0 to 14 d FCR, ending BW, and BW gain for Experiments 1 and 2 demonstrate that the optimal particle size may not have been achieved during these experiments. Therefore, future research should focus on further expanding the range of particle sizes tested (beyond 3,700 μm) from 0 to 14 d to identify the optimal average feed particle size during this growth phase.

Salmonella biofilms act as a continuous source for cross-contamination in the food processing environments. In this study, a stable rugose morphotype of Salmonella was first induced by sequential exposure to subinhibitory concentrations (SICs) of sodium hypochlorite (NaOCl) (ranging from 50 to 300 ppm over 18-day period) in tryptic soy broth. Then, rugose and smooth morphotypes of Salmonella Typhimurium ATCC 14028 and Salmonella Heidelberg ATCC 8326 were characterized for biofilm forming abilities on polystyrene and stainless steel surfaces. Rugose morphotype of both ATCC 14028 and ATCC 8326 exhibited higher Exopolysaccharide (EPS) formation than smooth morphotype (p ≤ 0.05). Also, the SICs of NaOCl (200 or 300 ppm in broth model) increased the biofilm formation ability of rugose morphotype of ATCC 8326 (p ≤ 0.05) but decreased that of ATCC 14028. The 2-day-old Salmonella biofilms were treated with biocidal concentrations of 50, 100, or 200 ppm NaOCl (pH 6.15) in water for 5, 10, or 20 min at room temperature. The biofilm reduction in CFU/cm2 for the rugose was lower than the smooth morphotype on both surfaces (p ≤ 0.05) by lethal NaOCl in water. Scanning electron micrographs on both polystyrene and stainless steel surfaces demonstrated that the rugose morphotype produced a denser biofilm than the smooth morphotype. Transmission electron micrographs revealed the cell wall roughness in rugose morphotype, which may help in tolerance to NaOCl. The gene expression data indicate that the expression of biofilm regulator (csgD), curli (csgA, csgB, and csgC), and cellulose (bcsE) was significantly increased in rugose morphotype when induced by sequential exposure of NaOCl SICs. These findings reveal that the rugose morphotype of S. Typhimurium and S. Heidelberg produced significantly denser biofilm on food contact surfaces, which also increased with sequential exposure to SICs of NaOCl in the case of S. Heidelberg, and these biofilms were more tolerant to biocidal NaOCl concentrations commonly used in the food processing plants.

SUMMARY Previous research has focused on providing improved feed form (FF) in the finishing growth phase of broilers (>28 d) to optimize performance. However, it may be more economical to improve FF in earlier growth phases (

Primary breeder companies are continuously striving to improve existing commercial broiler crosses to increase performance and reduce cost. The objective of this study was to evaluate the response of a new commercial broiler cross (Cobb MV × Cobb 500) under 4 different amino acid density (AAD) regimens on live performance and carcass yield during a 36 d grow-out period with 2 processings to collect data at 32 and 35 d. Two basal diets were formulated to low AAD (LAAD, digestible lysine, dLys 1.08, 0.95, and 0.87% for starter, grower, and finisher) and very high AAD (VHAAD, dLys 1.39, 1.26, and 1.12%). Medium and high AAD (MAAD and HAAD) diets were created by mixing the LAAD and VHAAD diets at ratios of 66.6:33.3 and 33.3:66.6, respectively. This was a randomized complete block design with 12 replications/treatment (16 birds/pen, 0.07 m2/bird). Feed intake/bird was reduced (P < 0.05) when birds were fed the VHAAD diet at 0–32 and 0–35 d. As AAD increased, FCR decreased significantly in a stepwise manner by approximately 4 points at each AAD level (P < 0.05). Feeding higher levels of AAD improved broiler live performance and carcass yields. At 33 d, birds fed the HAAD diet had the highest potential gross profit/bird, and at 36 d, birds fed the VHAAD diet had the highest potential gross profit/bird. Further research should evaluate the effects of feeding increased AAD diets to male and female Cobb MV × Cobb 500 separately, as well as in different feeding phases and longer grow-out periods.

In ovo injection of probiotics has been of interest for achieving early health benefits. However, there is limited research demonstrating where bacteria could migrate within the embryo after injection. The objective of this study was to evaluate bacterial colonization or migration after in ovo injection of broiler embryo with bioluminescent Escherichia coli. Injection using 106 CFU/mL nonpathogenic E. coli was applied to amniotic and air cell regions on day 18 of incubation. On days 18, 19, 20, and 21 the amnion, skin, lung, gastrointestinal tract (GIT), bursa, and spleen were collected. On day 21, the GIT was separated into crop, duodenum, jejunum, ileum, and ceca sections. All tissues were visualized using anin vivo imaging system to confirm the presence of bioluminescent E. coli. Samples were homogenized, 10-fold serially diluted, and spread onto appropriate agar to determine bacterial loads in all tissues. Results indicated that eggs injected into the amnion had significantly high numbers of E. coli cells in all tissues compared to air cell injected and control treatments 2 h post-injection (P < 0.0001). E. coli was also found on the lungs, spleen, and bursa of eggs injected either in the amnion or air cell (P < 0.05). Results indicated that in ovo injection into the amnion was more efficient than air cell injection, yielding a higher bacterial concentration in the evaluated tissues, specifically the ileum and ceca. Future research using bioluminescent probiotic bacteria may establish sites of preference for different probiotics leading to site-specific application that can maximize their overall impact when in ovo injected.