4Definitions Synchronization Rate: % of females detected in estrus compared to total number synchronized.Conception Rate:% of females pregnant compared to number of females inseminated.Pregnancy Rate:% of females pregnant compared to total number synchronized.
5Effect of synchronization rate on pregnancy rates
6Effect of synchronization rate on pregnancy rates
24Impact of Fixed-Time AI on Calving and Weaning TreatmentItemControlTAINo. of cows615582Weaning rate, %7884Weaning weight, lb176 ± 4a193 ± 4bab Means within row differ (P < 0.01)17 kg(Rodgers et al., 2011)
26Change in value based on herd sire costs Bull ValueItem$2,500$3,500$4,500Increased returns (increased value of AI calves)$58.33Decreased costs decreased costs of clean-up bulls)$29.55$39.29$49.04Decreased returns (Attributed to fewer clean-up bulls included in decreased costs calculation)$0.00Increased costs (additional labor, semen, AI supplies, etc.)$46.10Gain per cow exposed to AI$41.78$51.52$61.27
31Can I use sexed semen in beef cattle operations?
32Semen sorting overview MoFlo® Hands-On Training CourseNozzleForward FluorescencePhotodiode DNA ContentLaser beamDrop DelaySide Fluorescence OrientationObjectivePulse of Charge AppliedLast Attached DropChargedDeflectionPlatesSorting OverviewThe sorting takes place following the analysis in the Illumination Chamber. When a cell of interest is detected by the lasers and optics, a pulse of charge is sent through the stream when this cell of interest reaches the last attached drop. The droplet then breaks off with a charge that can be either positive or negative, depending on the sort direction. The droplets fall through the electric field created by the charge plates, and get deflected accordingly. The cells are then collected in the sample tubes.The sorting function involves many facets of the MoFlo that require very precise timing and calibration. The stability of the fluidics and droplet formation are critical with a jet-in-air sorter. Your MoFlo has been engineered to provide an extremely stable droplet break-off and charge on the droplets of interest. This translates directly to your sort purity.An accurate drop delay assessment is also critical to high sort purity. The drop delay defines the time duration for a particle to travel from the interrogation point at the laser to the “last attached drop”.With a stable fluidics and an accurate drop delay, cell sorting can reach very high purities of greater than 99%. Also, recoveries are optimized with stable fluidics and an accurate drop delay.These concepts described above are covered in detail throughout this module.+-+Waste Catcher+-+-Sort Receptacle32
33Gender ratio after 20% of cows are inseminated to sexed semen (Hall et al., 2010)
34Embryo Production of Superovulated Angus Cows 32.4%49.5%****Category** Treatments differ (P < 0.05)
35Recommendations for Embryo Transfer Utilize only in donors cows with known prolific production (average >10 transferable embryos per collection).Inseminate at 0, 12, and 24hr after estrus.Do not expect similar fertilization rates to conventional semen.
37Relationship between time of calving and lifetime production (Lesmeister et al., 1973)
38Influence of calving period on reproductive longevity (Cushman et al., 2012)
39Influence of calving period on weaning weights (Cushman et al., 2012)
40Factors affecting attainment of puberty Body weightAgeGeneticsNutritionReproductive managementRate of gainPlane of nutritionBody compositionAnimal handling
41Factors affecting attainment of puberty Body weightAgeGeneticsNutritionReproductive managementRate of gainPlane of nutritionBody compositionAnimal handling
42Factors affecting attainment of puberty Body weightAgeGeneticsNutritionReproductive managementRate of gainPlane of nutritionBody compositionAnimal handling
43Effect of timing of gain on attainment of puberty and reproductive performance Lynch et al., 1997 JAS 75:The objective of this study is to determine the influence of supplemental feeding of conserved perennial peanut forage on growth performance and age at puberty in growing beef cattle heifers.
44Effect of Timing of Gain on Reproductive Performance ADG, kg/d d0-112EVENGAINLATEGAIN – 0.11ADG, kg/d dEVENGAIN – 0.45LATEGAIN – 0.91ADG, lbs/d d0-168LATEGAIN – 0.45EVENGAINLATEGAIN(Lynch et al., 1997)
45Effect of Timing of Gain on Reproductive Performance Year 1ADG, kg/d d0-112EVENGAINLATEGAIN – 0.26ADG, kg/d dEVENGAIN – 0.80LATEGAIN – 0.95ADG, lbs/d d0-168EVENGAIN – 0.57LATEGAIN – 0.49EVENGAINLATEGAIN(Lynch et al., 1997)
46Effect of Timing of Gain on Reproductive Performance Year 2ADG, kg/d d0-112EVENGAINLATEGAIN – 0.05ADG, kg/d dEVENGAIN – 0.74LATEGAIN – 1.30ADG, lbs/d d0-168EVENGAIN – 0.53LATEGAIN – 0.50EVENGAINLATEGAIN(Lynch et al., 1997)
47Effect of Timing of Gain on Reproductive Performance Item EVENGAIN LATEGAINAge at puberty, dYearYear a bWeight at puberty, kgYearYearab Means within row differ (P < 0.01)(Lynch et al., 1997)
48Effect of Timing of Gain on Reproductive Performance Item EVENGAIN LATEGAINFirst service PR, %YearYearOverall PR, %YearYear(Lynch et al., 1997)
49Cassady et al., 2009, JAS 87:2255-2261 and JAS 2262-2273 Estrous cyclicity responses of heifers of distinct body conditions to energy restriction and repletion.Cassady et al., 2009, JAS 87: and JASThe objective of this study is to determine the influence of supplemental feeding of conserved perennial peanut forage on growth performance and age at puberty in growing beef cattle heifers.
51Resumption of estrous cycles Termination of estrous cycles DesignRestrictionRe-feeding(FAT)??BCS 7BCS 5Resumption of estrous cycles(MODERATE)Termination of estrous cyclesCassady et al., (2009)
52Change in BW, BCS and days to anestrus during feed restriction Treatments ItemMODERATEFATInitial BW, kg425a515bInitial BCS5.0a7.1bBW at anestrus, kg354380BCS at anestrus3.13.3Days to anestrus66.5a155.9bNEWCassady et al., (2009)
53Change in BW, BCS and days to 1st estrous cycle after initiation of feed repletion Treatments ItemMODERATEFATBW at anestrus, kg354380BCS at anestrus3.13.3BW at 1st estrous cycle, kg455a513bBCS at 1st estrous cycle5.2a6.0bDays to 1st estrous cycle67.778.9NEWCassady et al., (2009)