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Ammonia (NH3) produced inside livestock houses can adversely affect animal welfare and performance and degrade the environment. In broiler houses, NH3 levels are mitigated by applying acidifiers to the litter but acidifiers provide short-term NH3 suppression requiring heavy or repeated applications. Microbial additives may provide longer-term NH3 control through nitrogen (N) immobilization and nitrification. The objective of this 50-d lab study was to evaluate the impact of two microbial additives (Environoc 301 and Environoc 501), 2% glucose, and distilled water (control) treatments applied to broiler litter on NH3 emissions and litter properties. During the first 34 d, glucose significantly but modestly reduced NH3 emissions vs. the other treatments which were not significantly different from one-another. For the entire study, when glucose was excluded (due to lost replicates), the three treatments were not significantly different. The unreplicated glucose treatment had higher final litter nitrate concentration than the other treatments. Litter properties were unaffected by the two microbial additive and control treatments. The effectiveness of glucose in reducing NH3 emission could have been due to greater N immobilization and nitrification vs. the other treatments. More research on cost-effective labile carbon sources and higher application rates to achieve greater NH3 reduction is required.

Sodium bisulfate (SB) was evaluated on its ability to improve broiler growth and intestinal structure with(out) a coccidia challenge. One thousand two hundred Cobb500 day-old males were randomly assigned within 4 experimental groups with a 2 × 2 factorial design, with (out) SB in the diet and with(out) a day 0 coccidia challenge using a 10× dose of a commercial vaccine. At day 7, oocysts per gram of feces were determined. At day 0, 14, 28, and 41, BW and feed consumption were measured. At day 21, 20 birds per treatment were subjectively scored for coccidia lesions, and jejunal histologic samples were collected for villi measurements. Twenty additional birds were given fluorescein isothiocyanate-dextran to determine gut permeability. At day 41, 10 birds per treatment had histologic samples collected. Statistical analysis was conducted in JMP Pro 14 using GLM procedure to compare disease state and diet. Means were separated using Dunnett's test (P ≤ 0.05) with the nonchallenged standard diet treatment that is considered the control. All parameters measured indicated an effect due to the coccidia inoculation. Therefore, effects of diet on (non)challenged treatments were determined using a Student t test (P ≤ 0.05). Limited differences due to diet were seen for the nonchallenged production data. Sodium bisulfate had a thinner villi base width (P = 0.04) on day 21 and greater villi height (P = 0.03), smaller base width (P = 0.04), thicker muscularis (P = 0.03), and lower crypt: height ratio (P = 0.01) on day 41. Challenged SB had similar gut permeability to the nonchallenged control (P = 0.94) on day 21. There was no difference in flock uniformity, feed intake, oocysts per gram of feces, or lesion scores between challenged treatments. Challenged SB had greater BW on day 14 (P < 0.0001), 28 (P < 0.0001), and 41 (P = 0.02). Feed conversion ratio from day 0 to 14 was also lower (P = 0.0002). Challenged SB had smaller crypts (P = 0.02) and therefore a smaller crypt: height ratio (P = 0.03) on day 21. Challenged control had a larger apical width (P = 0.03) and thicker muscularis (P = 0.04) on day 41. Overall, the addition of SB during coccidial enteropathy aided in BW, feed conversion ratio, and villi health with no observed effects on parasite cycling.

Coccidiosis is a high-prevalence disease that annually entails huge costs for the poultry industry. Control of coccidiosis in poultry production is based on the use of coccidiostats and vaccines. However, along with the problem of drug resistance, there is a concern about food safety and drug residues in poultry products. The objective of this study was to evaluate the effect of sodium bisulfate (SBS) in comparison with monensin (M) and their combination (SBSM) effects on controlling coccidiosis in broilers. In a randomized design, 300 chickens (Ross 308) were divided into 5 treatments and 4 replications (15 birds per replicate). All birds, except the negative control (NC), were orally inoculated with 4 Eimeria species on 14 D of age. Treatments included were as follows: NC, an unsupplemented basal diet, nonchallenged; positive control, a basal diet unsupplemented, challenged with Eimeria spp; a basal diet supplemented with 5 g/kg of SBS; a basal diet supplemented with 1 g/kg of M; and a basal diet supplemented with 5 g/kg SBS and 1 g/kg M (SBSM). Oocyst shedding per gram (OPG) of the faecal sample from each experimental unit was counted on 5 to 14 D after inoculation. Two chicks from each experimental unit were euthanized to investigate intestinal lesions on day 5 after inoculation. The NC birds showed the highest BW gain and the lowest feed conversion ratio. The birds in the SBSM group had improved feed consumption compared with the M group in the prechallenge period (P < 0.05). All supplemented treatments resulted in a significant decrease in OPG. The M and SBSM treatments showed more efficacy than the SBS group (P < 0.05) in reducing OPG. There was a significant reduction in cecal lesions owing to supplementation with SBS, but the effect of SBS in the upper part of the intestine was lower than the M and SBSM groups (P < 0.05). Based on the results of this study, SBS has protective effects against coccidiosis in ceca, and the combination of M and SBS (SBSM) did not show any further improvement effect compared with M alone on the control of coccidiosis.

Salmonella and Campylobacter are considered major public health burdens worldwide, and poultry are known to be one of the main reservoirs for these zoonotic pathogens. This study was conducted to evaluate the effect of a commercial probiotic or direct-fed microbial (DFM) Calsporin (CSP), and prebiotic or mannan oligosaccharide (MOS) (IMW50) on ultrastructural changes and the villous integrity of intestinal mucosa in turkey poults challenged with Salmonella and Campylobacter. A 21-day battery cage study was conducted using 4 dietary treatments including a basal diet (corn and soybean–based) nonsupplemented and uninfected as a negative control (NC); basal diet supplemented with 0.05% DFM (CSP); basal diet supplemented with 0.05% MOS (IMW50); and basal diet supplemented with 0.05% mixture of DFM and MOS at equal proportions. Female large white turkey poults aged 336 days were obtained from a local commercial hatchery and randomly distributed in electrically heated battery cages with 12 treatments of 4 replicates per treatment containing 7 poults per pen. The first 16 pens were not infected with bacteria, poults in pens 17-32 were orally challenged at day 7 with 105 cfu Salmonella Heidelberg, and the poults in pens 33-48 were orally challenged at day 7 with 105 cfu Campylobacter jejuni. Feed and water were provided ad libitum throughout the study. At day 21, ileal tissue samples from 1 bird per cage were collected for intestinal integrity and ultrastructural examination by scanning and electron microscopy. DFM and MOS supplementation was effective in both challenged and nonchallenged (not infected with Salmonella and Campylobacter) birds. Goblet cells and mucus were increased, with the presence of large numbers of segmented filamentous bacteria in DFM- and MOS-supplemented groups compared with birds in control treatments. The number and size of villi were reduced in poults exposed to Salmonella and Campylobacter. Results show that CSP and IMW50 provide protection of ileal mucosal integrity in poults exposed to Salmonella or Campylobacter.

High levels of polyunsaturated fatty acids in avian sperm cause more susceptibility to lipid peroxidation. Aging in roosters reduces the antioxidant capacity of sperm and thus fertility. The purpose of this study was to investigate the effects of different levels of alpha-lipoic acid (ALA) as a feed supplement to improve the semen quality and fertility parameters of aged broiler breeder roosters and identification of its most effective level. A total of forty-two roosters at 45 wk of age were randomly assigned to 7 treatments (0, 15, 40, 70, 95, 120, and 145 mg ALA/bird per day) for 8 wk. Semen parameters and body weight were assessed biweekly, and testosterone plasma levels were determined in the 8th wk of the experimental period. Artificial insemination was performed at the end of the experiment to evaluate the fertility potential. The dietary administration of ALA had no significant effects on body weight, semen volume, average path velocity, linearity, straightness, wobble, the amplitude of lateral head displacement, beat-cross frequency, sperm concentration, morphology, plasma testosterone level, fertility, or hatchability (P > 0.05). Alpha-lipoic acid supplementations resulted in a significant decrease in seminal malondialdehyde concentration and immotile (type D) sperms (P

Based on research reports, feed characteristics can increase poult growth via several factors. Two rearing experiments (EXP) were conducted to test the effects of feed form and ingredient quality in turkey poults. Bird performance and the duodenum, jejunum, ileum, and cecum morphology were observed in both EXP. Poults were reared in battery cages (48 cages in EXP 1 and 72 cages in EXP 2). Four dietary treatments with differing feed form and function factors were evaluated in EXP 1. A completely randomized block design with a 2 × 2 × 2 factorial arrangement of treatments consisting of 2 levels of fines, 2 soybean meal (SBM) sources, and 2 levels of an enzyme cocktail (Rovabio Advance) was tested in EXP 2. Poult BW, BW gain (BWG), feed intake (FI), and feed conversion ratio (FCR) were determined in both EXP. Apparent metabolizable energy corrected for nitrogen (AMEn) was determined in EXP 2. Differences were considered to be statistically significant at P ≤ 0.05. Feeding increased feed crumble particle size with fewer fines in the starter feed resulted in an increased BWG accompanied by an increased FI. Reduced feed fines reduced AMEn when the dietary enzyme cocktail was not present. The feed formulation with 60% CP SBM resulted in a lower FI and an improved FCR. The enzyme cocktail interacted synergistically with screening and fed SBM source factors on the AMEn and FCR. It was concluded that both the feed form and quality, as used in this study, affect poult performance.

Salmonella and Campylobacter are leading human foodborne pathogens commonly associated with poultry and poultry products, and several methods to control these pathogens have been applied to poultry production. This study was conducted to evaluate the effect of CALSPORIN, (CSP), a direct-fed microbial (DFM), and yeast cell wall (Saccharomyces cervisiae, IMW50, a mannanoligosaccharide (MOS)-based prebiotic, on performance, levels of Salmonella and Campylobacter in the feces, and intestinal histomorphometry in turkey poults. A 21-day battery cage study was conducted using 4 dietary treatments, including: an unsupplemented basal diet (corn and soybean-based) as negative control (NC); basal diet supplemented with 0.05% DFM; basal diet supplemented with 0.05% MOS; and basal diet supplemented with 0.05% mixture of DFM and MOS at equal proportions. Female Large White turkey poults (n = 336) were randomly distributed in 6 electrically-heated battery cages with 4 treatments and 12 replicates per treatment (7 poults per replicate pen). The first 16 pens were not inoculated with bacteria, while poults in pens 17 to 32 were orally challenged at day 7 with 105 CFU Salmonella Heidelberg and the poults in pens 33 to 48 were orally challenged at day 7 with 105 CFU Campylobacter jejuni. Feed consumption, body weight, and feed conversion ratio were measured weekly and at the end of the experiment. At day 21, fresh fecal samples from each pen were collected for Salmonella and Campylobacter enumeration and ileal tissue samples were collected from 1 bird per pen for histomorphology examination. DFM and MOS supplementation was accompanied with reduced levels of Salmonella shed by the treated birds compared to the control group, and with increased body weight (P ≤ 0.05). The surface area of villi increased in the MOS-supplemented group compared to the control group (P ≤ 0.05). There was a significant difference in V:C ratio between supplemented groups and control group (P ≤ 0.05). Based on these results, there is potential for CALSPORIN and IMW50 to reduce Salmonella shedding in feces, enhance ileal mucosal health, and improve growth performance of turkey poults.

Salmonella and Campylobacter are frequent colonizers of the intestinal tracts of poultry and have often been associated with human foodborne illness. The entry, transmission, and prevalence of both pathogens have been extensively studied in chickens but little information is available for turkeys. This project monitored turkey breeder hens and toms from d of hatch to 65 wk of age with the objective of determining routes of transmission for Salmonella and Campylobacter throughout the turkey production cycle. Breeder poults were separated by sex and then into 2 groups (control and inoculated) for each sex. The inoculated group was orally gavaged with marker strains of both Salmonella and Campylobacter. The inoculated groups (toms and hens) were placed on the opposite side of a growout house from the uninoculated groups. Fecal samples, intestinal samples and organs, feed, drinkers, and potential vectors such as insects and mice, were analyzed at different times until 65 wk. Monitoring showed that Campylobacter spread rapidly and cross-contaminated turkeys throughout the growout house. For both Salmonella and Campylobacter, naturally occurring strains that were first isolated in control groups at wk 3 and 4, respectively, outcompeted marker strains several wk post inoculation and persisted in the flock. The most common naturally occurring strains were C. jejuni (tetracycline resistant), C. coli (kanamycin resistant), and S. Agona. Campylobacter and Salmonella also were isolated from flies and from a mouse, confirming the importance of proper pest control and biosecurity to reduce the spread of the bacteria.

Due to its potential environmental and public health impacts, emissions of ammonia (NH3) as well as several other gases from US livestock farms may be regulated. Broiler houses are important sources of NH3 emissions. However, there are no emissions data from roaster (8–12 wk old broilers, ∼4 kg ea.) houses. Producers treat the litter in broiler houses with acidifiers, such as sodium bisulfate (SBS, NaHSO4) to reduce ammonia production and protect bird health. However, there is very little data on the effect of acidifiers, particularly at high application rates on ammonia emissions. The impact of different SBS application rates [High (0.95–1.46 kg m−2, whole house), Medium (0.73 kg m−2, whole house), Low (0.37–0.49 kg m−2, whole house), and Control (0.37–0.49 kg m−2, brood chamber)] on ammonia emissions was evaluated in commercial roaster houses over 22 months spanning eight flocks. Ammonia emission from each fan was measured with an acid scrubber that operated only when the fan operated. Emissions were calculated using >95% measured data with the rest being estimated using robust methods. Exhaust ammonia–N concentrations were inversely correlated with the SBS application rates. Emission rates on animal unit (AU, where 1 AU = 500 kg live-mass) basis (ER, g d−1 AU−1) were reduced by 27, 13, and 5%, respectively, in the High, Medium, and Low treatments vs. the Control treatment (mean: 100 g d−1 AU−1, range: 86–114 g d−1 AU−1). Emission rates for the Control treatment measured in this study on roasters were mostly higher than ERs in the literature. Differences in ERs are not only due to diet, environmental and management conditions, but also due to measurement methods.

SUMMARY The reutilization of litter is currently a common practice in broiler production due to several environmental and economic factors. The application of litter amendments in broiler houses is a popular practice that can reduce ammonia emissions from recycled litter by converting them to nonvolatile ammonium. Sodium bisulfate (SBS) is one of the acidifiers frequently used in broiler houses. Broilers raised to 9 wk may require higher acidifier application rates to prevent unhealthy NH3 levels throughout the flock than broilers raised to smaller sizes. A study with 6 flocks of roasters was conducted under commercial conditions to evaluate 4 levels of SBS. In a farm with 8 houses, 4 treatments were evaluated. In the control treatment 0.49 kg/m 2 of SBS was applied to the brood chamber, whereas the low, medium, and high treatments received 0.49, 0.73, and 1.46 kg/m 2 , respectively, in the whole house. Data were obtained as the average of 2 houses with approximately 21,000 broilers per house in each of the 6 flocks evaluated. Results indicated no significant differences due to treatments on final average BW, FCR, mortality, or the majority of condemnation parameters. The significant reductions in NH3 levels observed in the whole flock across all 6 flocks receiving SBS treatments did not significantly improve broiler live performance or affect condemnations at the processing plant.

SUMMARY High ammonia levels in broiler houses can reduce bird performance. Broiler producers commonly use acidifiers to reduce ammonia build-up. In addition to improving broiler performance, acidifiers can also provide other ancillary benefits such as reducing propane and electricity use and increasing cake (caked litter) N content. In this 2-yr study involving 9 flocks, 4 levels of an acidifier (sodium bisulfate) were applied to commercial roaster houses in eastern North Carolina. The control treatment had a sodium bisulfate application rate of up to 0.1 lb/ft2 to the brood chamber, whereas the high, medium, and low treatments had application rates of up to 0.3, 0.15, and 0.1 lb/ft2, respectively, to the whole house. No treatment effect was observed on propane or electricity use. However, compared with published studies involving smaller broilers, roasters required lesser amounts of propane and electricity. Linear regressions of propane and electricity use as a function of ambient temperature may help with decision making in roaster production. Brooding accounted for 88% of propane consumption. Reduced pH in the high treatment compared with the other treatments led to significantly higher ammonium concentration in the cake.

SUMMARY Broiler production has the potential to cause water and air pollution. Acidifiers such as sodium bisulfate (SBS) can reduce ammonia (NH3) emissions from broiler houses; NH3 is an important air pollutant that also affects bird health. Due to their longer grow-outs, roasters may require higher acidifier application rates to prevent unhealthy NH3 levels during the flock than ordinary broilers. Changes in NH3 emission with acidifier use may affect the partitioning of the input nitrogen (N) among the different N output pathways. Accounting for these output pathways through N mass balance provides a complete picture of N as it cycles through the roaster house. In a 2-yr study involving 9 flocks of roasters, 4 levels of SBS were applied to the litter in commercial roaster houses. Whereas the control treatment received up to 0.49 kg/ m 2 to the brood chamber, the high, medium, and low treatments received up to 1.46, 0.73, and 0.49 kg/m 2 , respectively, to the whole house. Ammonia-N emission decreased and N removed in cake and litter increased with SBS application rate. Nitrogen output components were averaged over the 4 treatments and expressed as percent of total N input or per unit mass of live weight (LW). Ammonia-N emission during grow-out, bird N exported, and cake and litter N removed accounted for 17.3% or 11.2 g/kg of LW, 38.9% or 25.1 g/kg of LW, and 22.4% or 14.4 g/kg of LW, respectively. We accounted for 79.1% of the total N inputs, with NH3-N losses during layout probably constituting the bulk of the unaccounted N. In addition to uncertainties in measurements of inputs and outputs, other factors that limited the ability to close the N mass balance were exclusion of feathers during cake and litter sampling, soil N leaching, and nitrous oxide emissions.

SUMMARY The purpose of this experiment was to evaluate the relative bioavailability of Zn from Zn propionate relative to feed-grade Zn sulfate using BW gain and bone Zn as response criteria. For the first 7 d posthatching, chicks were fed a semipurified starter diet deficient in Zn (22 mg of Zn/kg). From d 8 to 21 birds were fed a control (20 mg of Zn/kg) semipurified diet containing ground corn, soy protein concentrate, and dextrose. The control diet was supplemented with 0, 6, or 12 mg of Zn/kg of diet from feed-grade Zn sulfate or organic Zn propionate. Using corn in the diet increased the level of phytate, an important Zn antagonist in nonruminant animals. As supplemental dietary Zn increased, a dose-dependent increase was observed in feed intake, weight gain, total Zn intake, tibia Zn concentration, and total tibia Zn. Zinc supplementation improved FE (feed:gain), but not in a dose-dependent manner. Relative bioavailability of Zn was determined using weight gain, tibia Zn concentration, and total tibia Zn, assuming a value of 100% for feed-grade Zn sulfate. Using relative slope assay, relative bioavailability of Zn propionate was 119, 116, and 116% compared with Zn sulfate, respectively. We concluded, based on these results, that bioavailability of Zn from organic Zn propionate is greater than feed-grade Zn sulfate in the presence of dietary phytate.

Locomotion problems in meat poultry have multifactorial etiology. A better understanding of normal gait and its influences on biomechanical aspects of leg bones among turkey genetic lines is important to prevent skeletal disorders and locomotion issues. The objective of this experiment was to determine the possible differences in gait kinetic and kinematic parameters of turkey strains and their effects on bone biomechanical properties. Four genetic lines, named A, B, C, and D, were obtained and raised in 48 floor pens with new pine shavings. Leg health issues were classified at 16 and 33 d of age. Fifteen turkeys from each strain with apparent normal legs and gait at 33 d of age were selected for gait analysis. These 15 turkeys were trained to walk on a pressure sensitive walkway and video was recorded to calculate articulation movements. These data also were analyzed to obtain kinetic and kinematic parameters of the gait cycle collected at 47, 84, 107, and 145 d of age. At 20 wk all turkeys were sacrificed, and legs were collected and frozen for analysis. Weights and morphologic measurements of the femur, tibia, and shank were recorded. Bone mineral density (BMD) and content (BMC) were obtained using DEXA. Femur and tibia strength were evaluated by a 4-point bending test and torsion test, respectively. Gait parameters changed as toms aged and some differences were observed among lines. Genetic lines differed on BMD, but not on BMC. Strain D had a higher BMD and smaller diaphyseal angle than strain C, characteristics that were correlated with stronger bones. Strain D also had the lowest incidence of leg problems while strain C had the highest. Furthermore, the D strain had a smaller vertical motion of the toe than strains C and B at 47 d and strain A at 145 d, indicating that the D strain had a more efficient gait. In summary, genetic strains differ significantly on gait parameters, which in turn impacts bone biomechanics.

4 Abstract: The objective of this research was to determine the effect of using nipple drinkers during brooding on the performance of Large White turkeys. There were 6 different drinkers tested: the control and 5 nipple drinker systems. The control was the Plasson Drinker and the nipple systems tested were the Plasson Easy Start (PES), Val-Co Turkey Drinker (VC), Lubing Traditional Nipple (LTN), Lubing EasyLine (LEL) and Ziggity TM Big-Z Activator (BZ). Three experiments were conducted with turkeys brooded using the 6 drinker types. Some nipple drinker treatments were used in the rearing periods. At 20 wk, Body Weight (BW) was reduced for toms brooded to 6 wk on the LTN and brooded and reared on the VC. The use of LEL and LTN (during brooding) resulted in improved Feed Conversion (FC) at 20 wk. Trial 2-experiment 1 with hens of two strains was terminated at 3 wk because of excessive mortality from dehydration with some drinker types. In trial 2 -experiment 2, there were no poult hydration issues. The BW of hens at 6 wk brooded on the Plasson Drinker and the VC were higher compared to the BW of hens brooded on the PES and the BZ with the BW of hens on the LEL being intermediate. The use of the LTN resulted in significantly lower hen BW compared with all other drinkers through 10 wk. By 16 wk, there were no longer differences in hen BW due to drinker type. Drinker type did not have an effect on hen FC. Nipple drinkers can be used effectively to brood turkeys with some types also being useful during the rearing period. However, poor quality, inactive, or diseased poults may be at risk for dehydration on some nipple drinker systems.

The effects of dietary supplementation of the direct-fed microbial (DFM) Primalac in mash or crumbled feed on histological and ultrastructural changes of intestinal mucosa was determined in 2 populations of poults; 1 with and 1 without a Salmonella spp. challenge. Three hundred thirty-six 1-d-old female Large White turkey poults were randomly distributed into 8 treatment groups with 6 replicates of 7 poults in each pen. The poults were placed on 1 of 4 dietary treatments in a 2 × 2 × 2 factorial arrangement (mash or crumble feed, with or without DFM, not-challenged or challenged at 3 d of age). The DFM groups were fed a Primalac-supplemented diet from d 1 until the last day of the experiment (d 21). At 3 d of age, 50% of the poults were challenged with 1 mL of 1010 cfu/ mL of Salmonella spp. (Salmonella enterica serovar Typhimurium, Salmonella Heidelberg, and Salmonella Kentucky) by oral gavage. The inoculated poults were housed in a separate room from nonchallenged controls. Feed and water were provided ad libitum for all birds. At d 21, 1 poult per pen (total of 6 poults per treatment) was randomly selected and killed humanely by cervical dislocation. After necropsy, the small intestine was removed, and tissue samples from duodenum, jejunum, and ileum were taken for light and electron microscopic evaluation. The DFM birds showed increased goblet cell (GC) numbers, total GC area, GC mean size, mucosal thickness, and a greater number of segmented filamentous bacteria compared with controls. Changes in intestinal morphology as observed in this study support the concept that poultry gut health and function, and ultimately bird performance, can be improved by dietary supplementation with DFM products such as Primalac as used in this study.

Leg problems and resulting mortality can exceed 1% per week in turkey toms starting at approximately 15 wk of age. Dietary supplementation of organic trace minerals (MIN) and 25-hydroxycholecalciferol (HyD) may improve performance, decrease incidence of leg abnormalities, and increase bone strength. Nicholas 85X700 toms were assigned to 4 treatments consisting of a factorial arrangement of 2 concentrations of MIN (0 and 0.1% of Mintrex PSe, which adds 40, 40, 20, and 0.3 mg/kg of Zn, Mn, Cu, and Se, respectively) and 2 concentrations of HyD (0 and 92 μg/kg of HyD). Diets were formulated to be equal in nutrient content and fed ad libitum as 8 feed phases. Feed intake and BW were measured at 6, 12, 15, 17, and 20 wk of age. Valgus, varus, and shaky leg defects were determined at 12, 15, 17, and 20 wk of age. Tibia and femur biomechanical properties were evaluated by torsion and bending tests at 17 wk of age. There were no treatment effects on BW. Only MIN significantly improved feed conversion ratio through to 20 wk of age. Cumulative mortality at 3 wk of age was greater among the MIN birds, but it was lower by 20 wk (P = 0.085). The MIN decreased the incidence of varus defects at 17 wk of age; shaky leg at 12, 15, and 17 wk of age; and valgus defects at 15, 17, and 20 wk of age. There were no MIN × HyD interaction effects on individual gait problems. Maximum load and the bending stress required for tibias to break in a 4-point assay were increased with MIN supplementation, especially when HyD was also added. Maximum shear stress at failure of femoral bones in a torsion assay was increased by supplementation with both MIN and HyD together. Dietary supplementation of MIN and HyD may improve biomechanical properties of bones. Dietary MIN supplementation may improve feed conversion of turkeys, likely by decreasing leg problems.

Temperature (TEM) and O(2) concentrations during the plateau stage of oxygen consumption are known to affect yolk utilization, tissue development, and thyroid metabolism in turkey embryos. Three experiments were conducted to evaluate these incubation effects on long bone development. Fertile eggs of Nicholas turkeys were used. In each trial, standard incubation conditions were used to 24 d, when the eggs containing viable embryos were randomly divided into 4 groups. Four experimental cabinets provided 4 TEM (36, 37, 38, or 39 degrees C) or 4 O(2) concentrations (17, 19, 21, or 23% O(2)). In the third experiment, 2 temperatures (36 and 39 degrees C) and 2 O(2) concentrations (17 and 23%) were evaluated in a 2 x 2 factorial design. Body and residual yolk weights were obtained. Both legs were dissected, and shanks, femur, and tibia weights, length, and thickness were recorded. Relative asymmetry of each leg section was calculated. Chondrocyte density was evaluated in slides stained with hematoxylin and eosin. Immunofluorescence was used to evaluate the presence of collagen type X and transforming growth factor beta. Hot TEM caused reduction of tibia weights and increase of shank weight when compared with cool TEM. The lengths of femur, tibia, and shanks were reduced by 39 degrees C. The relative asymmetry of leg weights were increased at 38 and 39 degrees C. Poult body and part weights were not affected by O(2) concentrations, but poults on 23% O(2) had bigger shanks and heavier tibias than the ones on 17% O(2). High TEM depressed the fluorescence of collagen type X and transforming growth factor beta. The O(2) concentrations did not consistently affect the immunofluorescence of these proteins. The chondrocyte density was affected by TEM and O(2) in resting and hypertrophic zones. In the third experiment, high TEM depressed BW, leg muscle weights, and shank length. Low O(2) reduced tibia and shanks as a proportion of the whole body. We concluded that incubation conditions affect long bone development in turkeys.

A study was conducted to determine 1) the effect of a dietary direct-fed microbial (DFM) on turkey poult performance, 2) the effect of a DFM on a Salmonella challenge, and 3) the effect of feed processing on the efficacy of the dietary DFM. Day-of-hatch Large White female poults were placed in 2 rooms in 2 Petersime batteries per room. Twelve pens of 7 birds each were used in each battery (24 pens per room, 336 birds total). One of 4 dietary feed treatments was assigned to each pen (6 pens per room for each diet). One room housed non-Salmonella-challenged poults, and the other room housed poults challenged with a 1-mL oral gavage of Salmonella (1010 cfu/mL). A single batch of starter ration was split into 4 parts and used to provide 4 dietary treatments: 1) mash feed with no DFM (M), 2) mash feed with DFM (Primalac; 0.9 kg/tonne of feed, MD), 3) pelleted (20-s steam conditioning at 80°C) and crumbled feed with no DFM (C), and 4) pelleted and crumbled feed with DFM (CD). Feed and deionized, distilled water were provided ad libitum. Data were collected and analyzed separately for each room. Mortality was recorded for each pen on a daily basis and totaled by week and for the 3-wk period. Individual BW and feed consumption, by pen, were measured weekly. Weekly and cumulative BW gains and feed to gain ratios (F:G) were calculated. Liver, spleen, total and lower intestinal tract weights, intestinal length, and most-probable-number Salmonella populations were determined for one randomly selected bird per pen. Feeding processed feed resulted in improved BW and F:G. Feeding the DFM improved 3-wk cumulative F:G in birds not gavaged and reduced relative intestinal weight in birds gavaged. Salmonella populations were reduced 1 log by feeding DFM. Dietary DFM improved bird performance, reduced Salmonella populations, and was not affected by feed processing.

Salmonella enteritidis (SE) colonizes the intestinal tract of poultry and causes food born illness in humans. Reduction of (SE) colonization in the intestinal tract of poultry reduces potential carcass contamination during slaughter. The purpose of this study was to investigate the effect of SE-specific yolk immunoglobulin (IgY) on prevention of SE colonization in orally infected broiler chickens. Commercial Single Comb White Leghorn (SCWL) hens were hyperimmunized with SE whole cell antigens. The presence of anti-Salmonella antibody, IgY and IgG in egg yolk and serum respectively, was monitored by Enzyme Linked Sorbent Assay (ELISA). Two hundred forty male `Ross 308` day old chicks were randomly assigned to 8 groups and 3 replications of 10 birds were grown for 42 days of experiment. Eight experimental groups identified with, S, P, A, SP, SA, AP, SPA, C. Four birds from four challenged groups (S), were orally inoculated with 1 mL of bacterial suspension that contained 1×106 CFU mL-1 S. enteritidis at 3 day of age. The groups that supplemented with antibody (A) received 15 mL of yolk contained antibody mixed per 3.84 mL of drinking water on day 1 and continuing for duration of the experiment. The probiotic treated groups (P) were received probiotic, 0.1% of feed and 0.5% of feed, until day 21 and 56 respectively. One group as control (C) did not received any treatment of probiotic and antibody. A-treated and A-P treated groups had significantly lower fecal shedding (p

Avian Influenza (AI) is a contagious disease of poultry which caused by type A influenza virus. In the present outbreak of AI in Iran, the isolates (H N ) were characterized as a low pathogenic form of the 9 2 virus. Outbreaks due to H N subtypes have been reported in many countries. Because the common 9 2 methods of control of outbreaks of AI may not be very effective to prevent and control of this disease, we decided to study the effect of egg derived antibody on reducing morbidity and spread of virus in a population of chickens by using so-called transmission experiments. Birds in test group (which received antibody in drinking water) had lower morbidity (p

The objective of this study was to evaluate the effects of dietary chromium (Cr), as chromium propionate, on measures of insulin sensitivity. Liver and muscle glycogen, and plasma glucose and non-esterified fatty acid (NEFA) concentrations were used as indicators of insulin sensitivity. In total, 288 newly hatched male Ross broilers were divided into 4 dietary treatments consisting of 0 (control diet analyzed 0.43 to 0.45 mg Cr/kg), 0.2, 0.4, or 0.6 mg supplemental Cr/kg diet, resulting in 4 treatments with 9 replicate pens per treatment containing eight birds per pen. At d 21, 2 birds per cage were removed based on the greatest deviation from pen mean BW, resulting in each pen containing 6 birds for the final analyses. Final BW were taken on d 40, and on d 42 two birds from each pen were sampled for plasma NEFA, glucose, and muscle and liver glycogen determination at the initiation and termination of a 22 h fast. The remaining 2 fasted birds were sampled after a 30 min refeeding period. No differences were observed in feed intake, BW gain, or feed efficiency on d 21 or d 40. Liver glycogen tended (P=0.10) to be greater in Cr-supplemented chicks in the fed state, and muscle glycogen concentrations tended (P=0.07) to be greater in Cr-supplemented chicks compared with controls following fasting and refeeding. Plasma glucose concentrations were not affected by dietary Cr in the fed, fasted, or refed state. Plasma NEFA levels were not affected by treatment in fed or fasted birds. However, plasma NEFA concentrations were lower (P

Anti-nutritional factors (ANFs) in feed ingredients can challenge gut health and reduce nutrient utilization. Birds typically activate their innate immune system as a protective response against the adverse effects of ANF, which often involves the secretion of mucin. Although dietary supplementation of exogenous enzymes are commonly used to alleviate the adverse effects of ANF on apparent nutrient digestibility, little is known about how they affect gut health, particularly in relation to the morphological development and mucin secretion of enteric mucosa. We carried out two trials to examine the effect of dietary supplementation of different types of exogenous enzymes on gut health of by accessing the effect of jejunum morphological development and ileal enteric adherent mucin thickness layer in turkeys. Dietary β-mannanase supplementation reduced ileal adherent mucin thickness layer (804 vs 823 μg/g; p

4 Abstract: Embryo heart rates were measured on 400 fertilized turkey eggs (399 viable embryos) at 4 day intervals beginning at day 12 of development. Heart rates varied directly with eggshell porosity and were significantly and positively correlated with eggshell conductance (G) and conductance constants (k) but not with initial egg weight. When only eggs with embryos that died were analyzed the significant correlation coefficients increased. In a second experiment, eggshell pores were occluded to reduce G then heart rates were measured. Heart rates decreased concomitantly with decreases in G. In the final experiment, approximately 15,912 eggs were weighed individually to calculate G for each egg and were then incubated. Embryo survival was noted in High and Low G groups. Embryo heart rate and cardiac physiology in each group was measured. Low G reduced heart rates and improved embryo survival and cardiac physiology compared to High G. Thus, cardiomyopathy due to High G and its consequent lack of energy for myocardial function may contribute to turkey embryo mortality late in development.

Embryo and hatchling survival diminish as turkey breeder hens age. Recent data indicated that a chelated calcium proteinate (CCP) additive given to turkey breeder hens improved embryo survival as hens aged but did not affect shell thickness. We hypothesized that the mechanism by which this occurred may be by improved functional shell quality and its consequent effect on cardiac physiology. To test the hypothesis, CCP was supplemented to the diet of Large White turkey breeder hens for a 25 week egg production period and compared with controls without supplementation. Eggshell conductance, conductance constants, poult growth and cardiac physiology were measured at weeks 10, 18 and 25 of production. Because elevated temperatures increase heart rates and reduce heart weight and survival, half of the eggs was incubated at 37.9°C whereas the remaining eggs were incubated at 37.5°C. Embryos and poults from the CCP group exhibited increased heart weights and improved cardiac health. The hatching poults from CCP-fed hens also grew faster for the first 3 d of life. We conclude that CCP improves eggshell conductance, and the subsequent eggshell conductance constant (k) of eggs from turkey breeder hens. The change in k improved embryo cardiac health and poult BW after hatching.

The adverse effects of non-starch polysaccharides (NSP) on turkeys fed wheat-based diets may be alleviated by dietary supplementation of endoxylanase (to reduce the adverse effects of digesta viscosity) or phospholipase (to improve the digestibility of fat). BUTA toms were fed wheat-based diets containing one of 5 enzyme treatments: unsupplemented control, Natugrain Blend® (> 5,500 EXU/kg diet; NB), Lyxasan®-50 (> 2,250 EXU/kg diet; LX50), Lyxasan®-100 (> 5,500 EXU/kg diet; LX100), and Phospholipase (> 500 PLU/kg diet; PL) (BASF, Germany). Each treatment group was assigned to 8 pens containing 12 birds to evaluate growth performance (1-128 d), and 2 pens of 12 birds (excluding LX50) for the apparent metabolizable energy N-corrected (AMEn) and ileum viscosity determination (56-128 d). All enzyme treatments improved growth performance. In comparison to the control, dietary enzyme increased (P < 0.05) BW and decreased 1-128 d feed/gain (2.45 vs 2.37, P < 0.005). PL was most effective in reducing feed/gain during the starting phase and LX100 during the finishing phase, while NB had intermediate benefits throughout the experiment. PL increased AMEn from 9 to 12 wk, while NB and LX-100 resulted in the highest AMEn during the later finishing period. Viscosity was significantly higher for PL than the other treatments (13.5 vs 7.07 cP, P < 0.001). Growth performance and energy utilization of turkeys fed wheat-based diets can be significantl y enhanced by phospholipase supplementation of starter feeds and endoxylanase supplementation of growing and finishing feeds. However, enzyme blends may provide a positive response regardless of turkey age.

The hypothesis was proposed that the improved embryonic livability observed when higher incubation temperatures were imposed on eggs stored for 15 d prior to setting might have basis in energy metabolism. To test the hypothesis, fertilized turkey eggs were incubated either for the first 2 wk of development (experiment 1) or only the first week of development (experiment 2) at 37.8 degrees C compared with controls incubated at 37.5 degrees C. In both experiments, eggs were stored for either 15 or 3 d prior to setting. Viable embryos were selected randomly from each storage-by-incubation period treatment combination at 25 to 28 d of incubation and were sampled for blood, heart, and skeletal muscle tissues. Tissues were weighed and assayed subsequently for glucose or glycogen content. In experiment 2, the randomly selected embryos from each treatment combination were sampled at 7, 14, 21, and 28 d of incubation. Embryos at 7 and 14 d were assayed on a whole body basis, whereas at 21 and 28 d the bodies were dissected, and heart, liver, and skeletal muscle tissues were weighed and assayed for glycogen and lactate. Blood samples were collected between 25 and 28 d of incubation as in experiment 1 and assayed for glucose, creatine kinase, lactate dehydrogenase, and thyroid hormone concentrations. In both experiments, accelerated development was noted due to higher temperature and enhanced embryonic carbohydrate metabolism, and elevated thyroid hormone concentrations were observed compared with controls. It was concluded that a possible mechanism for the improved livability of faster growing embryos observed after prolonged egg storage might be due to better utilization of carbohydrate.

Large White turkey breeder hens were used to evaluate the effect of three different levels of physical feed restriction on subsequent body and carcass composition. The four feed treatments were 1) ad libitum fed throughout the study (CC), 2) feed restricted from 16 to 24 wk (CR), 3) feed restricted from 3 to 16 wk (RC), and 4) feed restricted from 3 to 24 wk (RR). Feed restriction was implemented so that RC and RR hens achieved a 45% reduction in BW compared to CC hens at 16 wk. From 16 to 24 wk, feed was allotted to RR and CR hens to maintain a slight increase in BW. At the completion of each restriction period, hens were gradually returned to ad libitum feeding. At 30 wk, hens were photostimulated for a 20-wk summer season egg production cycle. Restricted fed hens had increased moisture levels at 16 and 30 wk and decreased fat levels at 16, 30, 39, and 54 wk (P < or = 0.05). Absolute and relative weights of the pectoralis major muscle were greater in hens fed ad libitum through 43 wk (P < or = 0.05). There were no differences in the number of maturing yellow follicles due to treatment. However, restricted fed hens had higher peak egg production during early lay but decreased subsequent and cumulative egg production. Changes in egg production were associated with changes in breast muscle weight. Prolactin levels were greater in hens in-production compared to hens out-of-production; however, there were no differences due to feed treatment. In conclusion, further research on quantitative feed-restriction programs, which result in body weight reductions as described in this study, should address specific physiological and nutritional requirements and not be implemented as general programs.

A study was conducted to evaluate the effects of mannanoligosaccharides (MOS), bambermycins (BAM), and virginiamycin (VIR) on the growth performance of male turkeys. Hybrid Large White male poults were assigned to six dietary treatments: control, MOS, BAM, VIR, MOS+BAM (MB), and MOS+VIR (MV). All diets were formulated to meet NRC (1994) nutrient requirements. There were eight replicate floor pens per treatment with 20 birds per pen reared from 1 to 140 d. Body weight and feed conversion (FC) were collected at 3-wk intervals and at 20 wk of age. Mortality and culled birds were recorded daily. All treatments except MV significantly (P < 0.05) increased 20 wk BW. Body weight was increased at 12 wk by BAM, whereas VIR increased BW at Weeks 12 and 15. All treatments improved FC for Weeks 0 to 3, whereas VIR, MB, and MV improved FC for Weeks 0 to 12 and 0 to 18. There were no treatment effects on cumulative mortality or cull rate. Dietary supplemental MOS, BAM, and VIR resulted in improved growth performance of Large White turkeys. These results indicate that MOS may be utilized as an alternative to antibiotic growth promotants to improve turkey performance.

The hypothesis was proposed that embryonic growth could be influenced paternally in the absence of changes in egg weight or eggshell conductance. Sire families were established by selecting 11 sires based on blood sampling of approximately 50 commercial turkey males. Southern blot analysis was used to identify the most distantly related individuals in the subpopulation. Five hen siblings or half-siblings of the males were randomly assigned to each male to randomize effects of egg size and eggshell conductance. Artificial inseminations were performed weekly for 17 wk, using each sire with the assigned hens. Fertilized eggs were collected and set in incubators at biweekly intervals. Offspring were observed at the time of hatching for sex, body weight, and blood glucose concentration. Significant differences among sires were observed at hatching for poult weights and blood glucose concentration, and a significant correlation between the BW and glucose concentration was noted. Progeny of sires with the highest and lowest BW and blood glucose concentrations were subsequently compared. Mean BW of poults from different sires differed by as much as 10 g, although they were hatched from eggs of the same weight. Elevated blood glucose was associated with heavier BW; heavier heart, liver, and muscle weights; a rapid utilization of glycogen at pipping; and increased gluconeogenesis as measured by plasma organic acids and glucose-6-phosphatase activity. We conclude that poult embryonic growth differs even when not mediated by egg size and functional characteristics.

The objective of this study was to determine the effect of turkey breeder hen age on the efficacy of different antibiotics commonly used in the turkey industry against poult Escherichia coli isolates. Intestinal isolates demonstrated more incidences of resistance to chlortetracycline (CTC), gentamicin (GEN), enrofloxacin (ENO), neomycin (NEO), and sulfadimethoxine-ormetoprim (SDM-ORM) when cultured from poults from young hens (YHP, 15 weeks of lay) (p ≤ 0.05). Liver isolates demonstrated varied hen age differences to GEN (p ≤ 0.05). However, liver isolates cultured from YHP showed higher levels of resistance to NEO and SDM-ORM and lower levels of resistance to ENO (p ≤ 0.05). All isolates cultured were resistant to clindamycin (CLD) and bacitracin (BAC), and no less than 96.6% of the isolates cultured were resistant to penicillin (PEN). Isolates from Hatchery 1 and 2 exhibited strong susceptibility to ENO, but, in Hatchery 3, results to ENO varied. The results were more variable when breeder flocks were followed from young to old, which may be due to pronounced seasonal effects. In conclusion, E. coli isolates from YHP have a higher incidence of resistance to antibiotics than E. coli isolates from OHP. These data suggest that age of breeder flock and hatchery-related environmental differences might influence the effectiveness of antibiotics against avian E. coli isolates from turkey poults.

The negative correlation between selection for rapid growth and embryonic survival was investigated. Embryonic growth was assessed with hatchling weights of a closed population of commercial turkey breeders. Hatchling weights were highly significantly (P < 0.0001) and positively correlated with blood glucose concentrations at hatching. This relationship existed for both tom and hen poults. Significant differences among dams for hatchling blood glucose were observed. Further experiments examined dams selected for producing poults hatching with high (High) or low (Low) blood glucose concentrations. The High embryos were in larger-sized eggs with the same eggshell conductance but with significantly lower conductance constants than the Low embryos, suggesting that Low had longer incubation periods. High embryos grew faster than Low embryos with elevated organ glycogen concentrations. Organic acid analysis indicated elevated plasma alpha-ketoglutarate, urate, and beta-hydroxy butyrate concentrations, suggesting a greater reliance on gluconeogenesis for the High group. Posthatch growth was significantly positively correlated with hatchling blood glucose concentrations in toms but not in hens. Tom poults hatching with elevated glucose were heavier than low glucose hatch mates until 22 wk of age, but hen poults displayed no differences until 16 wk when High hens weighed less than Low hens. These data suggest that the negative correlation between rapid growth and embryonic survival is related to egg-shell conductance constants and embryonic energy metabolism.

Ammonia (NH 3 ) in broiler houses can degrade bird performance. Acidifier such as, sodium bisulfate (SBS) applied to litter inside broiler houses can reduce NH 3 release and thus improve bird performance. While there are multiple studies on acidifier effects on inside NH 3 concentrations in broiler houses, there are no studies in roaster houses where big broiler birds are grown for 8 to 12 wk. The impact of different SBS application rates - High (1.46 kg/m 2 , whole house), Medium (0.73 kg/m 2 , whole house), Low (0.49 kg/m 2 , whole house), and Control (0.49 kg/m 2 , brood chamber) on inside NH 3 concentrations was evaluated over six flocks of roaster chickens (~4 kg ea.). Ammonia concentrations were measured with acid scrubbers that sampled air at two locations (mid-house, end-house) 0.15 m above the litter. Inside NH 3 concentrations were much higher in the cool-season versus warm-season flocks. Generally, higher acidifier application rates provided better NH 3 suppression. Ammonia concentrations were ≤10 ppm during brooding, as well as for the entire duration of most warm-weather flocks with the High and Medium treatments. In the Low treatment, NH 3 concentrations were ≤25 ppm during brooding but approached or exceeded 25 ppm with the Control treatment. During brooding, the High, Medium, and Low treatments resulted in significantly lower mid-house NH 3 concentrations of 3, 6, and 14 ppm, respectively, versus the Control treatment (24 ppm). For a 62-d flock, mid-house NH 3 concentrations were significantly lower in the High and Medium treatments versus the Control treatment; concentrations in the High, Medium, and Low treatments were reduced by 47%, 32%, and 20%, respectively, versus the Control treatment.

Clostridium perfringens is recognized as an enteric pathogen in humans, domestic animals, and livestock. This organism is associated with necrotic enteritis, gangrenous dermatitis, clostridial dermatitis (turkeys), and gizzard erosions in poultry. This study was conducted to evaluate the effectiveness of a direct-fed microbial (DFM), Primalac (Star Labs, Clarksdale, MO), in preventing intestinal colonization of turkey poults with C. perfringens. One-day-old turkey poults (n = 128) were randomly divided into 4 treatments with 4 replicates (8 birds/pen). Treatments were as follows: 1) basal diet without DFM (C); 2) basal diet supplemented with Primalac (1.5 kg/ton; PM); 3) basal diet with poults gavaged with C. perfringens (CCP); and 4) basal diet supplemented with Primalac and poults gavaged with C. perfringens (PMCP). Feed and water were provided ad libitum throughout the trials, and birds were inoculated with C. perfringens (10(8)cfu/mL) on d 3 and 7. On d 21, 2 birds/pen were killed, spleen and bursa of Fabricius were collected and weighed, and cecal contents were used for C. perfringens enumeration. Feed consumption, BW, and feed conversion were calculated throughout the trial (weekly and cumulatively). Data were analyzed using GLM of SAS (SAS Institute, Cary, NC; P0.05). Among the inoculated groups, birds fed the DFM-supplemented diet had significantly lower cecal C. perfringens counts than the birds fed the diet without the DFM. The C. perfringens (log(10) cfu/g) in ceca were as follows: C, 5.88; CCP, 7.26; PM, 5.35; PMCP, 6.19 ± 0.36. No differences were observed for BW (814 ± 11 g), feed conversion (1.33 ± 0.03), organ weights, or relative organ weights. Further studies are needed to fully ascertain the potential of using DFM to reduce the numbers of C. perfringens in the gastrointestinal tract of turkey poults.

A field survey was conducted to study the association between mouth lesion incidence (LI) and egg shell quality in commercial laying hens. Hens in 5 groups of cages were examined for number of mouth lesions and body weight. Eggs collected by group were evaluated for egg weight (EW), shell weight (SW), % shell, and shell surface density (SD). Eight farms were used that involved 2 strains, 2 age groups, and 2 management levels. The relationships between egg shell quality factor means and number of lesions per hen by strain, age, and management level were determined using correlation and regression. Lesion incidence was negatively correlated with EW and SW. There was a linear decrease in both EW and SW as LI increased and this decrease was greater in young birds than in old. There were no overall effects of LI on % shell or SD. However, SD decreased more in poor management birds than good as lesion incidence increased.

Large White turkey breeder hens from a strain exhibiting poor hatchability were fed thyroid-altering diets. The following dietary treatments were fed to randomized groups of hens for 15 wk of egg laying: 1) 16.5% protein turkey breeder diet (control), 2) the control diet containing 2.1 ppm supplemental iodine, 3) the control diet containing .1% thiouracil, and 4) the control diet containing .5 ppm triiodothyronine (T3). Blood samples were taken from hatching embryos from hens fed each diet. Embryonic hearts and livers were weighed prior to and during pipping as well as after hatching. Blood plasma was analyzed for thyroxine (T4), T3, and glucose. Livers were assayed for glucose-6-phosphatase activity. Supplemental maternal dietary iodine elevated embryonic T4 concentrations prior to pipping. Dietary T3 and iodine increased hepatic glucose-6-phosphatase activity and blood plasma glucose concentration prior to pipping. Feeding thiouracil increased embryonic liver weights but decreased heart and body weights. Blood plasma T4 was elevated in embryos from hens fed thiouracil but blood glucose levels were depressed because of a lack of increased glucose-6-phosphatase activity. Feeding iodine decreased the enzyme activity at internal pipping. It is suggested from the data that maternal thyroid metabolism may influence hatchability via embryonic thyroid and carbohydrate metabolism during hatching.

Broiler production results in the production of ammonia, and at high concentrations, ammonia can affect bird performance, and hence, productivity. When released into the environment through ventilation, ammonia can adversely affect public health and the environment. Because of its environmental and health impacts, ammonia emissions from animal feeding operations may be regulated by the EPA. Acidifying amendments have been shown to be effective in reducing ammonia emissions from poultry operations. The purpose of this study is to evaluate in-house ammonia concentrations and emissions from four commercial heavy-broiler houses in eastern North Carolina receiving four levels of PLT® (a commercial amendment): control (0.37 – 0.49 kg/m2 center brood area), low (0.37 – 0.49 kg/m2 whole house), medium (0.73 kg/m2 whole house), and high (>0.73 kg/m2 whole house). Ammonia concentrations were measured with acid scrubbers and ammonia emissions were calculated from exhaust ammonia concentrations and ventilation volumes. Based on monitoring of three flocks (September 2007 to May 2008), in-house ammonia-N concentrations decreased with increasing PLT application rates. A medium application rate was adequate for maintaining ammonia levels at or below 25 ppm for 9-wk grow-out period during the spring. Based on data from three flocks, ammonia emission factors (only grow-out) for the control, low, medium, and high treatments were 1.06, 1.12, 0.97, and 0.92 g/bird-d, respectively. These emission factors are mostly higher than those reported in the literature mainly because they represent heavier (>4 kg) and older (9-wk) birds fed a higher protein diet. Acid scrubbers proved to be suitable for measuring time-averaged ammonia concentrations for a wide range of values. Emissions data will be collected for four more flocks and PLT impacts on bird performance and energy use will also be quantified.

Shuttle programs involving dietary supplementation of mannanoligosaccharides (MOS) and virginiamycin (VM) were evaluated in turkeys by their effects on growth performance, body weight uniformity, and carcass yield characteristics. Diets containing no growth promoter (control), VM (22 mg/kg), or a shuttle program (MOS-VM) of MOS (0 to 6 wk of age at 500 mg/ kg) and VM (6 to 14 wk of age at 22 mg/kg) were fed to Hybrid female turkeys. All diets were formulated to exceed NRC nutrient requirements. Each treatment was assigned to 8 replicate floor pens containing 20 birds that were reared from 1 to 98 d of age. Body weights and feed consumption were recorded at 3-wk intervals, and mortality and culled birds were recorded daily. At the conclusion of the trial, 2 birds per pen were randomly chosen for carcass yield analysis. Feeding VM alone significantly (P < 0.05) increased body weight compared with control fed birds during all periods. The MOS-VM shuttle program resulted in early growth depression for birds less than 3 wk of age, possibly influenced by an unplanned cold stress, but better growth than the nonmedicated control birds after 6 wk of age. Birds fed VM had superior (P < 0.05) feed conversion ratio from 0 to 3 wk, which persisted until 14 wk (P < 0.10). There were no treatment effects on overall feed consumption, uniformity, mortality, or cull rate. Processing yields or weight of various parts were also unaffected by treatment.

An experiment was conducted to determine the effect of dietary P levels and dietary phytase enzyme (E) inclusion on Large White turkey breeder hen reproductive performance from 31 to 62 wk of age. Hens were placed in a curtain-sided house with 48 pens (10 birds per pen; 8 pens per treatment) at 31 wk and were fed a breeder ration with treatments as follows: HP, dietary available P = 0.55%; HPE, HP + E; MP, dietary available P = 0.35%; MPE, MP + E; LP, dietary available P = 0.17%; and LPE, LP + E. Feed and water were available ad libitum for 28 wk of lay. Diets were fed in mash form, and all other nutrients were formulated to meet or exceed NRC requirements. All hens were photostimulated in January (31 wk) with 15.5 h of light daily. Production data were recorded on a pen basis. Individual bird BW and feed consumption, by pen, were determined at monthly intervals from 31 to 62 wk. Hens were observed for weekly reproductive performance for hen housed egg production, hen-day egg production, settable eggs, cumulative settable eggs, hens out of lay, and hen mortality and for biweekly performance for egg fertility, hatchability of all eggs, hatchability of fertile eggs, egg weight loss, conductance, conductance constant (k), and embryonic mortality. Egg weight, eggshell thickness, egg components, and albumen and yolk P were measured monthly. At 62 wk of age, hen tibia P, plasma P, total fecal P, and water-soluble fecal P were determined. Decreasing dietary P resulted in no decreases in reproductive performance for turkey breeder hens to 62 wk. Additionally, decreased dietary P resulted in decreased total fecal P and water-soluble fecal P. Feeding turkey breeder hens dietary phytase enzyme resulted in significantly fewer hens going out of lay; however, this was not reflected in hen housed egg production. It was concluded that phosphorus could be lowered in turkey breeder hen diets, compared with current surveyed industry levels, without impairing reproductive performance.

The effects of hen age, Escherichia coli, and dietary Bio-Mos and Flavomycin on poult performance from 1 to 21 d were studied. Day-of-hatch BUTA (BIG-6) male poults were gavaged orally (1 mL) with approximately 10(8) cfu/mL E. coli composed of four serotypes or sterile carrier broth. A mixture of the same E. coli cultures was added to the poults' water troughs to attain a concentration of approximately 10(6) cfu/mL on a weekly basis to ensure a continuous bacterial challenge. Within each E. coli split plot treatment group, poults from hens of different ages (33 and 58 wk of age) were fed diets containing Bio-Mos (1 g/kg feed), Flavomycin (2.2 mg active ingredient/kg feed), Bio-Mos plus Flavomycin, or a control diet, in a randomized complete block design. This experiment yielded eight treatments per challenge group. At Weeks 1 and 3, eight birds from each treatment from the E. coli challenged and unchallenged groups were randomly chosen for bacterial sampling of liver and intestinal tissue for coliforms, aerobic bacteria, and Lactobacillus spp. E. coli isolates from tissue samples were O serotyped. During E. coli challenge, dietary Bio-Mos and Flavomycin improved poult BW and BW gains (P < or = 0.05). When poults were not challenged with E. coli, poults from old hens had improved BW and cumulative BW gains over poults from young hens (P < or = 0.05). Cumulative 3-wk BW gains for unchallenged poults from young hens were improved by Bio-Mos and Flavomycin (P < or = 0.05) alone and in combination when compared to the control diet. Two of the four E. coli serotypes administered were recovered. Several serotypes were recovered that were not administered. It may be concluded that dietary Bio-Mos and Flavomycin can improve the overall performance of poults, especially when they are faced with an E. coli challenge.

Juvenile turkey hens were actively immunized against vasoactive intestinal peptide (VIP) prior to photostimulation to evaluate its effect on enhancing egg production. VIP antibody titers were generated in the VIP immunized hens and a greater rate of egg production per hen was observed compared to controls. In addition, the first egg laying cycle was extended for an additional 7 wk without a significant decline in egg production. Over a 27-wk period, 116 settable eggs per hen were produced from the VIP immunized hens as compared to 102 and 90 eggs for the keyhole limpet hemocyanin and saline control groups, respectively. Based on the increased egg production and the extension of the first egg laying cycle, this experiment demonstrates that VIP immunization of turkey hens is potentially economically relevant.

A novel product (SQ12) for subcutaneous (SQ) injectable delivery of oxytetracycline (OTC) has been developed for use in livestock. SQ12 employs microfluidic spheres encasing OTC crystals, which allows for longer release of the OTC compared with other injectable antibiotics. The objectives of the study were to determine serum and tissue levels of SQ12 in turkey breeder hens to 14 days postinjection and to evaluate effects of SQ12 on reproductive status. Thirty photostimulated hens were housed in litter floor pens and provided with 14.5 hr of light per day in a curtain-sided facility. Six hens served as untreated controls. Twelve hens per treatment group received SQ injections in the neck with SQ12 at 11.4 (L dose group) or 22.7 mg/kg (H dose group) to assess low and high doses, respectively. Serum samples were obtained from each hen at predose and 6, 12, 24, 48, 72, 96, 168, 240, and 336 hr postinjection. All hens were euthanatized at 14 and 15 days postinjection. One-half of the hens in each treatment group were sampled (liver, lung, kidneys, and breast muscle) for tissue residue levels of OTC. The control group had no detectable OTC in serum or tissues at any sample collection time. There were no detectable serum levels of OTC in either treatment group prior to injection. The average serum concentrations of the L and H dose groups showed similar depletion curves although the H dose group was 42% higher at maximum concentration than the L group. Average tissue concentration of OTC for all tissues sampled from the H dose group was twice that of the L dose group. All tissue levels were below the OTC residue tolerance limit. SQ12 provided an extended source of OTC in serum of turkey breeder hens with no effect on reproductive status. SQ12 may provide for a novel treatment of bacterial infection in turkey breeder hens with longer lasting serum levels compared with other single injectable OTC products.