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| 1 | Performance,litter quality and gaseous odour emissions of broilers fed phytase supplemented diets显示文摘The effect of graded levels of phytase on performance, bone characteristics, excreta/litter quality and odorant emissions was examined using 720 Ross 308 male d-old broilers. A 2 x 4 factorial arrangement of treatments was employed with 6 replicates of 15 birds per pen. Factors were: diets-positive and negative control(PC, NC); phytase-0, 500,1,000.1,500 FTU/kg. The PC was formulated to meet the 2014 Ross 308 nutrient specifications, whereas the NC was formulated with lower Ca(-1.4 g/kg), available P(-1.5 g/kg), Na(-0.3 g/kg), dLys(-0.2 g/kg) and MEn(-0.28 MJ/kg) equivalent to nutrient matrix values for 500 FTU/kg phytase in the starter,grower and finisher periods(i.e.,downspec diet). On d 24, phytase decreased FCR by 1.6, 4.3 and 4.6 points at inclusion levels of 500.1,000 and 1,500 FTU/kg, respectively(P < 0.01) across all diets. Phytase by diet interactions on BW gain were observed on d 24 and 35(P < 0.01). The effect of phytase was much more pronounced in the NC diet as compared with the PC diet.On d 24, phytase increased BW gain by 37, 55 and 68 g in the PC and 127.233 and 173 g in the NC at 500,1,000 and 1,500 FTU/kg, respectively. Diet by phytase interactions were also observed for tibia ash, litter quality and water to feed intake ratio(P < 0.01) with higher phytase effect in NC as compared with PC.Neither diet nor phytase impacted excreta moisture content on d 18 or 21(P> 0.05). Solid phase microextraction gas chromatography-mass spectrometry(SPME-GC-MS) analysis of gaseous emissions on d 39 indicated no difference in the emission of alcohols, aldehydes, ketones, volatile fatty acids and phenols between treatments(P> 0.05). The results indicate that phytase has greater benefits when formulated using nutrient matrix values as compared with adding it over the top in an already nutrient sufficient diet. The later method would be expected to increase feed costs without concomitant performance benefits. | Nishchal K.Sharma Mingan Choct Shu-Biao Wu Robert Smillie Natalie Morgan Amal S.Omar Nisha Sharma Robert A.Swick | 2016 | Animal Nutrition2016，，4： | 3 |
| 2 | An early feeding regime and a high-density amino acid diet on growth performance of broilers under subclinical necrotic enteritis challenge显示文摘Broilers that have early access to feed have been shown to have enhanced immune system and gut development and heightened resilience against necrotic enteritis(NE). This study examined the effect of early feeding a high amino acid density diet on performance of broilers under a sub-clinical NE challenge model. Ross 308 broilers(n = 576) were assigned to a 2 × 2 × 2 factorial design with 2 feeding regimes(feed access either within 6 h post-hatch or after 48 h post-hatch), 2 diets(control diet or the control diet with an additional 10% digestible amino acids [HAA]) and either presence or absence of NE challenge.Oral administrations of Eimeria species(d 9) and a field strain of Clostridium perfringens(d 14) were used to induce NE, Broiler performance was analysed at d 13.23.30 and 35, Intestinal lesion score and bacterial count were analysed on d 16. The NE challenge reduced overall bird performance and induced severe intestinal lesions, without causing notable mortality. At d 23 bird weight was significantly lower(P < 0.001) in the challenged birds compared with the unchallenged birds, but by d 30 the challenged birds had recovered and challenge no longer had an impact on bird performance. Birds fed the HAA diet had greater body weight by d 35 and heightened Lactobacillus content in the ileum at d 16(P < 0.05).Birds that were fed the HAA diet after a period of fasting performed better in terms of feed conversion ratio(FCR) under challenge. The findings from this study suggest there are beneficial effects of feeding high amino acid diets to birds in response to external stresses, such as post-hatch fasting and subclinical NE. | Chake Keerqin Shu-Biao Wu Birger Svihus Robert Swick Natalie Morgan Mingan Choct | 2017 | Animal Nutrition2017，，1： | 1 |
| 3 | Myosin light chain phosphorylation and growth cone motility 显示文摘 | JOHN T S PATRICIA MORGAN NATALIE DOWELL BYUNGHEE LEU | 2002 | Journal of Neurobiol2002，52，3： | 1 |
| 4 | Suicidal Behavior, Negative Affect, Gender, and Self- Reported Delinquency in College Students 显示文摘 | Jennifer Langhinrichsen-Rohling Catalina Arata David Bowers Natalie O' Brien Allen Morgan | 2004 | Suicide & Life : Threatening Behavior2004，34，3： | 1 |
| 5 | Abductive statistical methods improve the results of calibration curve bioassays:An example of determining zinc bioavailability in broiler chickens显示文摘In this paper,we discuss the theory behind calibration curve experiments and their application to a zinc(Zn)bioavailability study with broiler chickens.Seven replicates of 16 male commercial broiler chicks were fed starter diets for 14 days.Six diets had different levels of a potential Zn source and one was a positive control with standard industry levels of Zn for comparison.Four commonly used methods of calculating bioavailability means and confidence intervals(CI)from a calibration curve(standard curve)experiment to estimate the bioavailability of a new zinc source in broiler chickens were compared.The methods compared were the following:1)the Counter-Intuitive Method uses a multiple-range test to compare unknown test and standard samples;2)the Intuitive Method uses standard linear regression and inverts the equation to predict Zn bioavailability for each replicate of test samples;3)the Abductive Method uses Graybill's Equation,based on theory and observation,to estimate CI's;and 4)the Sophistic Method uses reverse regression,and calculates Zn bioavailability values directly from the equation.The Counter-Intuitive Method only gives information about which standards the test samples are,or are not,significantly different from respectively(average available Zn not predicted).The Intuitive Method ignores error about the standard curve and theoretically cannot estimate the CI directly(X±SEM=107.5±15.8 mg Zn/kg).The Sophistic Method underestimates and overestimates the test sample mean values above and below the mean of the standards,respectively(X=96.6 mg Zn/kg).The Abductive Method has an advantage over the other methods:The mean prediction estimation is consistent with theory(107.5±6.1 mg Zn/kg;X±SEM).When test or“unknown”samples are near the mean of the standard samples,the CI is smaller than when near the extremes of the calibration curve.When calibration curve error is small(R^(2)>approximately 0.95),there is little advantage to using the Abductive Method,but when calibration curve error is larger,as in many bioassays with growing animals,the Abductive Method improves the accuracy of the CI calculations.The Abductive Method was used to demonstrate the influence of the number of replicate samples on experimental power and cost. | Gene M.Pesti Lynne Billard Shu-Biao Wu Robert A.Swick Thi Thanh Hoai Nguyen Natalie Morgan | 2022 | Animal Nutrition2022，，3： | 0 |
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