Introduction to Fetal Programming Dr. Jeff Lehmkuhler Extension Beef Specialist Animal & Food...
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Transcript of Introduction to Fetal Programming Dr. Jeff Lehmkuhler Extension Beef Specialist Animal & Food...
![Page 1: Introduction to Fetal Programming Dr. Jeff Lehmkuhler Extension Beef Specialist Animal & Food Sciences ANR Update Fall 2013.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9d5503460f94a861f9/html5/thumbnails/1.jpg)
Introduction to Fetal Programming
Dr. Jeff LehmkuhlerExtension Beef SpecialistAnimal & Food SciencesANR Update Fall 2013
![Page 3: Introduction to Fetal Programming Dr. Jeff Lehmkuhler Extension Beef Specialist Animal & Food Sciences ANR Update Fall 2013.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9d5503460f94a861f9/html5/thumbnails/3.jpg)
Bovine Fetus Size
• 35 days
• 90 days
• 120 days
• 180 days
• 240 days
![Page 4: Introduction to Fetal Programming Dr. Jeff Lehmkuhler Extension Beef Specialist Animal & Food Sciences ANR Update Fall 2013.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9d5503460f94a861f9/html5/thumbnails/4.jpg)
Barker Hypothesis
• Fetal Origins Hypothesis = Fetal Programming
• Traced back 1944 Nazi occupied Holland
• Calorie ration down to ~ 500 / d
• Offspring higher disease rates
![Page 5: Introduction to Fetal Programming Dr. Jeff Lehmkuhler Extension Beef Specialist Animal & Food Sciences ANR Update Fall 2013.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9d5503460f94a861f9/html5/thumbnails/5.jpg)
Fetal Programming
• Maternal stimuli during pregnancy that can affect fetal development, as well as postnatal growth & health
• Maternal plane of nutrition influences / alters genetic expression of offspring
• In some species, lasts for several generations
• Provide opportunity of phenotypic variation in “Fixed” genotypes = Epigenetics
![Page 6: Introduction to Fetal Programming Dr. Jeff Lehmkuhler Extension Beef Specialist Animal & Food Sciences ANR Update Fall 2013.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9d5503460f94a861f9/html5/thumbnails/6.jpg)
Epigenetics• Heritable changes in gene expression resulting
in alterations to chromatin structure– DNA methylation, Histone modification
(acetylation), noncoding microRNAs
http://micro.magnet.fsu.edu/cells/nucleus/chromatin.html
![Page 7: Introduction to Fetal Programming Dr. Jeff Lehmkuhler Extension Beef Specialist Animal & Food Sciences ANR Update Fall 2013.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9d5503460f94a861f9/html5/thumbnails/7.jpg)
DNA Methylation Example
• Most DNA is methylated (CH3)– Regions not methylated are close to regulatory region
• Variation in methylation in different tissues
• S-adenosylmethionine = methyl donor influenced by diet
• Gestating Ewes restricted folate, vitamin B12, betaine, choline, methionine = obesity and impaired immune systems of progeny as adults
![Page 8: Introduction to Fetal Programming Dr. Jeff Lehmkuhler Extension Beef Specialist Animal & Food Sciences ANR Update Fall 2013.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9d5503460f94a861f9/html5/thumbnails/8.jpg)
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Oct Nov Dec Jan Feb Mar Apr May June July Aug Sept
2-year old
3-year old
5-year old
Estimated Net Energy Requirementsfor 2-, 3-, and 5-year old Cows
Calving
Months Since Calving1996 Beef NRC
Breeding Season
Wean
Mca
l/d
75% Fetal
Growth
First Trimester
![Page 9: Introduction to Fetal Programming Dr. Jeff Lehmkuhler Extension Beef Specialist Animal & Food Sciences ANR Update Fall 2013.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9d5503460f94a861f9/html5/thumbnails/9.jpg)
Past Thoughts
• Dry, mid-gestational cow lowest nutritional needs
• Best time to “cheat” nutritionally
• Little fetal development = low nutrient need
• High supplementation during late gestation = heavier Birth Weights
Were We Wrong?
![Page 10: Introduction to Fetal Programming Dr. Jeff Lehmkuhler Extension Beef Specialist Animal & Food Sciences ANR Update Fall 2013.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9d5503460f94a861f9/html5/thumbnails/10.jpg)
Placental Development
• Placentome = Cotyledons (Fetus) + Caruncles (Maternal)
• Growth occurs throughout gestation– First 2/3 of gestation primary growth
• Growth slows last trimester
• Blood flow 4.5-fold increase last ½ gestation
![Page 11: Introduction to Fetal Programming Dr. Jeff Lehmkuhler Extension Beef Specialist Animal & Food Sciences ANR Update Fall 2013.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9d5503460f94a861f9/html5/thumbnails/11.jpg)
Nutrition & Placenta
• Nutrient restriction during early/mid-gestation– Lowered placentome weight
– Altered Vascularity of placenta
– Protein Supplementation on Day 190 = 2X blood flow
– Restriction reduces number of cotyledons, not caruncles
![Page 12: Introduction to Fetal Programming Dr. Jeff Lehmkuhler Extension Beef Specialist Animal & Food Sciences ANR Update Fall 2013.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9d5503460f94a861f9/html5/thumbnails/12.jpg)
Fetal Organ Development
• Restricted Cows from day 30-125 of gestation– Fetuses had enlarged hearts & brains
– Feeding cows back to same condition score by day 220 of gestation = No differences by d 245
– Vascular of intestines, size of liver, lungs, pancreas, kidney, perirenal fat have also been shown to be impacted by nutrition of the dam
![Page 13: Introduction to Fetal Programming Dr. Jeff Lehmkuhler Extension Beef Specialist Animal & Food Sciences ANR Update Fall 2013.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9d5503460f94a861f9/html5/thumbnails/13.jpg)
Maternal Nutritional Restriction on Fetal Muscle Development
Du et al., 2010 JAS
Muscle Fiber Numbers SETNo Increase after Birth
![Page 14: Introduction to Fetal Programming Dr. Jeff Lehmkuhler Extension Beef Specialist Animal & Food Sciences ANR Update Fall 2013.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9d5503460f94a861f9/html5/thumbnails/14.jpg)
Muscle Development
• Animals born with set number of muscle fibers• Hypertrophy occurs after birth = Muscle fiber
size increases
• Low priority tissue = Susceptible to deficiency
![Page 15: Introduction to Fetal Programming Dr. Jeff Lehmkuhler Extension Beef Specialist Animal & Food Sciences ANR Update Fall 2013.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9d5503460f94a861f9/html5/thumbnails/15.jpg)
Nutrient Restriction Skeletal Muscle
• Nutrition during pregnancy explained 20% of variation in birth weight (Robinson et al., 2013)
• Current research shows mixed results on muscle fiber number / diameter / carcass traits
![Page 16: Introduction to Fetal Programming Dr. Jeff Lehmkuhler Extension Beef Specialist Animal & Food Sciences ANR Update Fall 2013.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9d5503460f94a861f9/html5/thumbnails/16.jpg)
What’s Been Reported – Few Examples
Restriction
• Early preg negative impact on sow placenta, myogenesis = growth, carcass (Foxcroft 2006)
• Protein Deficiency last 100d in cows = delayed puberty (Corah 1975)
• Calf BW reduced protein deficiency 2nd trimester (Micke 2010)
Overfeeding
• Ewes overfed had progeny that were leptin resistant = obesity (Long 2010)
• Heifers had lower milk production when suppl 1st Trimester (Sullivan 2009)
Supplementation
• Protein suppl lower morbidity (Mulliniks 2013)
• Suppl lower post-weaning morbidity (Larson 2009)
![Page 17: Introduction to Fetal Programming Dr. Jeff Lehmkuhler Extension Beef Specialist Animal & Food Sciences ANR Update Fall 2013.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9d5503460f94a861f9/html5/thumbnails/17.jpg)
Timing of Cow Nutritional Plant & Impacts on Cattle
Light = Time of nutrition
Dark = When Impacts Progeny
![Page 18: Introduction to Fetal Programming Dr. Jeff Lehmkuhler Extension Beef Specialist Animal & Food Sciences ANR Update Fall 2013.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9d5503460f94a861f9/html5/thumbnails/18.jpg)
So What = Theories
• We know – Birth weight, Colostrum, and placental development impacted
• We don’t know – Consistently what impact this will have on growth, fertility, health, etc…
• Add’l research in area will be forthcoming and help unravel
![Page 19: Introduction to Fetal Programming Dr. Jeff Lehmkuhler Extension Beef Specialist Animal & Food Sciences ANR Update Fall 2013.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9d5503460f94a861f9/html5/thumbnails/19.jpg)
Recommendations?
• Manage diet to meet / slightly exceed nutritional requirements at various stages of production
• Critical points are late gestation / early lactation / early gestation– Often overlooked, hay quality ??, grass availability??,
fescue toxicity??
• Maintain BCS in 5-6 at critical points, Keeping Cows at Par / + Energy balance = Fertility
![Page 20: Introduction to Fetal Programming Dr. Jeff Lehmkuhler Extension Beef Specialist Animal & Food Sciences ANR Update Fall 2013.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9d5503460f94a861f9/html5/thumbnails/20.jpg)
Mineral Update
• Matthews/Burris et al. Selenium Research– Support mix of organic / inorganic Se in mineral
• Grass tetany– Can occur in fall / winter– Lush pasture (N & K fertilizer) & cereal grain silage
• Spreadsheet comparison of IRM Rec to 4 oz
![Page 21: Introduction to Fetal Programming Dr. Jeff Lehmkuhler Extension Beef Specialist Animal & Food Sciences ANR Update Fall 2013.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9d5503460f94a861f9/html5/thumbnails/21.jpg)
Forage Quality
• Going to be mixed = Recommend testing
• Late cuttings may be low quality
• Late Late cuttings may have vegetative regrowth to offset quality
• Second cuttings should be decent
• Silage quality likely quite good (high grain content)
![Page 22: Introduction to Fetal Programming Dr. Jeff Lehmkuhler Extension Beef Specialist Animal & Food Sciences ANR Update Fall 2013.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9d5503460f94a861f9/html5/thumbnails/22.jpg)
Thoughts / Questions
Underfed Cow?