creased (P
dent-intruder score (RIS) was given for the number <strong>of</strong> attacks (0, 1, or 2)during the two tests. Genetic type and sex were both found to besignificant for attack latency (P < 0.03 and P < 0.04, respectively) andRIS (P < 0.05 and P < 0.01). On average, pigs <strong>of</strong> the new genotypeattacked 22 seconds faster and 0.20 more times than old genetic pigs andgilts attacked 22 seconds faster and 0.27 more times than barrows.Commercial pigs from 2005 were more aggressive toward a foreign pigthan commercial pigs from 1980. One interpretation <strong>of</strong> these results isthat selection for increased lean growth rate has resulted in correlatedchanges in behavior.Key Words: Genetics, Behavior, Pigs31 A comparison <strong>of</strong> bygholm sieve to standard particle sizeanalysis techniques. C. Benz*, M. Tokach, C. Groesbeck, S. Dritz,R. Goodband, J. Nelssen, and J. DeRouchey, Kansas State University,Manhattan.Two experiments were conducted to evaluate the Bygholm Feed SieveParticle Size Tester (BFS). The BFS is a 28 × 6 × 11 cm plastic boxdivided into four compartments by three screens (3, 2, and 1 mm mesh)to estimate mean particle size. The BFS is a simple method developedby Danish researchers at the Bygholm Research Centre to immediatelyestimate particle size in a feed mill. In Exp. 1, mean particle size <strong>of</strong> 30ground corn samples were evaluated using the BFS operated accordingto manufacturer′s directions. Samples were analyzed without balls orwith two rubber balls placed on the 2 mm screen and one ball placed onthe 1 mm screen. Samples also were analyzed with a Ro–Tap 13–sievestack (53 to 3,350 Μm Tyler mesh screens) according to ASAE methods.Particle sizes ranged from 543 to 1,082 Μm using the Ro–Tap.Adding the balls to the BFS did not improve the accuracy <strong>of</strong> the predictionequations (R 2 = 0.80 vs. 0.82). Thus, all subsequent analyses wereconducted without balls. In Exp. 2, 25 additional ground corn samples(604 to 1,741 Μm) were analyzed to validate the linear regression equationdeveloped in Exp. 1. Results indicated that 90% <strong>of</strong> particle sizevalues were predicted within 100 Μm <strong>of</strong> the particle size when thesamples were less than 1,000 Μm; however, only 69% <strong>of</strong> samples withlarge particle sizes (> 1,000 Μm) were predicted within 100 Μm. Addingquadratic terms to a model using all samples allowed development <strong>of</strong>a more robust regression equation to predict particle size using the BFSmethod (particle size, Μm = -1172 + 69.709w + 25.297x + 0y + 25.518z- 1.173w 2 + 0.1151x 2 + 0.2139y 2 - 0.055z 2 , where w, x, y, and z are thepercentages <strong>of</strong> the sample above the 3, 2, 1 mm screens and base,respectively; R 2 = 0.92). This equation predicts that 85% <strong>of</strong> the samplesevaluated using the BFS will be within 100 Μm <strong>of</strong> the Ro-Tap methodparticle size and 98% <strong>of</strong> all samples to be within 150 Μm. These resultsindicate the BFS is a low cost method to estimate particle size in feedmills.Key Words: Particle size, Corn32 Effects <strong>of</strong> estradiol on the uterine environment and trophectodermin the gilt. T. Wilmoth*, D. Smith, J. Koch, and M.Wilson, West Virginia University, Morgantown.In the pig, it has been suggested that the size <strong>of</strong> the placenta during lategestation is influenced by the size <strong>of</strong> the embryo at elongation. Treatment<strong>of</strong> Meishan gilts with estradiol at the time the embryo is producingestradiol and elongating, caused a dramatic increase in placental size.The objectives <strong>of</strong> the current experiment were to determine how estradioltreatment during elongation would alter the uterine luminal environmentand what effect, either directly or indirectly, that estradiol wouldhave on the rate <strong>of</strong> trophectoderm proliferation. We utilized commercialcrossbred gilts (n=12) which were checked for estrous behavior twicedaily for at least two normal cycles (17-22 days). Each gilt was thenbred by AI at 12 and 24 h following the onset <strong>of</strong> estrus. Beginning onday 12, half <strong>of</strong> the gilts were randomly assigned to receive estradiol (1mg) every 6 h. On day 14, embryos and the associated uterine flushingswere collected. Embryos were fixed and embedded in paraffin for laterdetermination <strong>of</strong> trophectoderm proliferation. Uterine flushings wereclarified by centrifugation and snap frozen for later determination <strong>of</strong> theconcentrations <strong>of</strong> estradiol, IGF-I, prostaglandin (PG) F2Α, and PGE2.Trophectoderm proliferation was determined by sectioning the embryosat 10 Μm and immunohistochemically staining them for proliferatingcell nuclear antigen (PCNA) and counterstaining with hematoxylin.The proportion <strong>of</strong> PCNA positive nuclei in four fields were thendetermined. Treatment <strong>of</strong> gilts with estradiol increased the uterine luminalcontent <strong>of</strong> PGE2 (P=0.059) and PGF2Α (P=0.085) compared tocontrol gilts. The proportion <strong>of</strong> PCNA positive cells in the trophectoderm<strong>of</strong> embryos collected from gilts that were treated with estradiolwere approximately 33% greater than those from control treated gilts. Itappears that the dramatic increase in placental size at term followingadministration <strong>of</strong> estradiol during elongation may be a result <strong>of</strong> an indirecteffect <strong>of</strong> estradiol on the rate <strong>of</strong> proliferation <strong>of</strong> the trophectoderm.Key Words: Estradiol, Trophectoderm, Uterine environment33 Milk production and pregnancy rate <strong>of</strong> dairy cows in an invitr<strong>of</strong>ertilization embryo transfer program. L. E. Rensink* 1 , J. D.Helmus 1 , D. C. Arnett 1 , J. S. Metzger 2 , G. W. Robinson 2 , and A. N.Scheaffer 1 , 1 Northwestern College, Orange City, IA, 2 Trans Ova Genetics,Sioux Center, IA.An embryo transfer program in production dairy cows <strong>of</strong>fers a reproductivemanagement technique to <strong>of</strong>fset artificial insemination. We areworking in collaboration with Trans Ova Genetics (TOG) investigatingprocedures that would make embryo transfer <strong>of</strong> IVF embryos availableto the dairy industry. At this writing, TOG has transferred 4928 embryoswith a 28-d pregnancy rate <strong>of</strong> 34.7%, while the expected pregnancyrate in lactating dairy cows with AI is 20 to 25%. Estrous wassynchronized with OvSynch and was selected as a recipient after rectalpalpation and ultrasonographic examination <strong>of</strong> ovarian structures. Whenexamining the complete set <strong>of</strong> cows that were in the ET program cowsand diagnosed as pregnant at d 28 produced less milk and were fewerDIM (75 vs. 72 lbs and 180 vs. 215 d respectively). A subset <strong>of</strong> thisgroup (n = 91) was examined at one farm and no difference was detectable,however, a numerical decrease in DIM was observed. Body conditionscore was evaluated at the time <strong>of</strong> implant and 28-d later. BCS at thetime <strong>of</strong> implant for cows that were pregnant at d 28 was 2.86 and thosethat did not become pregnant had a similar BCS <strong>of</strong> 2.84. Yet, at the d 28palpation exam the cows that established a pregnancy had an averageBCS <strong>of</strong> 2.93 and the non-pregnant cows had a numerically lower BCS <strong>of</strong>2.81. This data indicates that cows that establish pregnancy from an ETprogram are similar in condition, produce less total milk, and are earlier11
- Page 1: Table of ContentsAbstractPageNumber
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- Page 9 and 10: height. About 5 g of cecum content
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- Page 15 and 16: 37 Hormone concentrations of produc
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- Page 19 and 20: 50 Environmental factors affecting
- Page 21 and 22: tions did not differ among treatmen
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- Page 25 and 26: 67 Effect of feeding reduced phosph
- Page 27 and 28: 73 Effect of feed intake level, bod
- Page 29 and 30: Ruminant Nutrition79 Effect of impr
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- Page 33 and 34: Menten (GMM) functions. Two pig spe
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- Page 37 and 38: 103 Relationship between dietary fa
- Page 39 and 40: 112 Effects of supplementing natura
- Page 41 and 42: 118 Application of 2-hydroxy-4-(met
- Page 43 and 44: 124 Ruminant diet composition effec
- Page 45 and 46: 131 Impact of fiber types on rumen
- Page 47 and 48: 138 Sow and litter performance in i
- Page 49 and 50: 147 Structural correctness and mobi
- Page 51 and 52: 153 Propionate regulation of feed i
- Page 53 and 54: 161 Genetically improving the produ
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- Page 57 and 58: tus ventralis and the infraspinatus
- Page 59 and 60: three weeks for the remainder of th
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ies have indicated that a sizable p
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lower urine pH (P < 0.0001) and blo
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204 Effect of weaning age on nurser
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Ten Broeck*, D. Clopton, R. Bott, M
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creasing DDGS. Forage intake in hay
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(Avena sativa; SW) to oat harvested
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offal from 26,231 head; and 406,405
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heritability and gain during the 20
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ackgrounding (BG) and finishing (F)
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having rancid, bloody, and bitter f
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to 14, and was higher (P < 0.03) in
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261 Effects of supplemental RDP ver
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ammonia, and total VFA increased ov
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Dairy Extension Symposium - Innovat
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tion of nonpregnant cows early post
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285 Effect of feeding diets contain
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291 Effect of dietary flaxseed, fla
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Edmonton, AB. Canada, 2 Department
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capillary number density (CND)) by
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allowed to expose for 2 weeks, deve
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of sulfur (1700 ppm) and fed with r
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correlated (r=0.56; P
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Table 1. CDR (% of BLUP) for S1-S5
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Author IndexASAS/ADSA Midwestern Se
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Jenschke, B., 170Jiménez, E., 307J
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Stahly, T. S., 66Stalder, K., 9, 56