Feed the cow properly in gestation to set-up the calf for long-term success potential.
By Ron Scott, PhD, Director of Beef Research and Technical Services for Purina Animal Nutrition for Livestock Plus (Reprinted with permission)
Will your next calf crop produce a show winner or pasture leader? The answer to this question may be determined before calving season begins. Before a calf even hits the ground, that animal may be predestined for a lifetime of greatness or mediocrity, thanks to a phenomenon called “fetal programming.”
Though there are environmental and nutritional factors that will play a role in that animal’s life, by birth, much of a calf’s lifetime health and performance potential already are determined. And that’s not just thanks to the genetics it inherited from both sire and dam. A lot has to do with the dam’s nutrition during pregnancy, too.
Fetal programming, or the impact of fetal development on long-term performance, was initially explored in human medicine. Now, animal science researchers are learning more about the lifelong effects on cattle that can be traced back to their fetal development.
Because 75 percent of fetal growth in calves occurs during the last two months of gestation, it once was thought that reduced maternal nutrition earlier in pregnancy was not harmful to the fetus. But consider that, in the first three months after conception, the following are developed in the fetus:
· Muscle fibers
· Limbs
· Ovaries and testicles
· The rumen, reticulum and omasum
· Critical organs including the pancreas, liver, lungs, brain and kidneys.1
As gestation progresses, all of these organs continue to grow and develop, with some being completely formed prior to birth. For example, muscle fibers do not increase in number after birth2 – whatever muscle growth potential a calf has already is decided before it takes its first meal. And the sites for intramuscular fat accumulation and marbling formation also are created during fetal development.
If dams are undernourished, organ development of the fetus will take precedence over skeletal muscle development. So, while muscle is one of the most critical factors in economical cattle production, it is the first thing to suffer if maternal nutrition is compromised.
That’s why a steady plane of nutrition for dams throughout pregnancy is so important. Can you imagine a human medical doctor advising a pregnant woman to steadily loseweight throughout her pregnancy? Yet that’s exactly what we often do with our pregnant beef cows.
A growing body of research is starting to show that there are no “do-overs” in fetal development. Among recent findings in studies looking at fetal programming and development are:
· Steers from cows nutritionally restricted during gestation had reduced body weight and carcass weight at 30 months of age compared to steers from cows fed on a steady plane of nutrition.3
· Marbling scores decreased in steers from under-nourished dams compared to those from dams that were fed 100 percent of NRC (2000) requirements.4
· Heifers born from supplemented dams later had increased adjusted 205-day weaning weights, prebreeding weights, weight at pregnancy diagnosis and improved pregnancy rates compared to heifers born to non-supplemented dams.5
· Heifers from supplemented dams reached puberty faster compared to those from non-supplemented dams.6
· Steers from cows grazed on improved pasture from 120 to 180 days gestation had increased weight gains, final weight, hot carcass weight and back fat – as well as improved marbling scores - compared to steers from cows grazed on native range.7
· Fewer steers from cows supplemented with protein required treatment for sickness in the feedlot, compared to offspring from non-supplemented dams.8,9
Considering the sizable investment of time, technology and financial resources that we make in working to improve cattle genetics, it is time to focus now on helping offspring fully express their genetic potential; this begins during gestation.
By providing pregnant cows the steady nutrition they need and maintaining consistent body condition year-around through SustainedTM Nutrition, we can make even faster genetic progress, and maximize the health, performance and value of every new generation of calves.
Ron Scott, PhD, is Director of Beef Research and Technical Services for Purina Animal Nutrition. Visit www.cattle.purinamills.com to learn more about SustainedTMNutrition and fetal programming.
References
1Hubbert, W. T., O. H. V. Stalheim, and G. D. Booth. 1972. Changes in organ weights and fluid
volumes during growth of the bovine fetus. Growth 36:217–233.
2Stickland, N. C. 1978. A quantitative study of muscle development in the bovine foetus (Bos
indicus). Anat. Histol. Embryol. 7:193–205.
3Greenwood, P. L., L. M. Cafe, H. Hearnshaw, D. W. Hennessy, and S. G. Morris. 2009.
Consequences of prenatal and preweaning growth for yield of beef primal cuts from 30-
month-old Piedmontese and Wagyu-sired steers. Anim. Prod. Sci. 49:468-478.
4Du, M., J. Tong, J. Zhao, K. R. Underwood, M. Zhu, S. P. Ford, and P. W. Nathanielsz. 2010.
Fetal programming of skeletal muscle development in ruminant animals. J. Anim. Sci. 88
(E. Suppl.):E51-E60.
5Martin, J. L., K.A. Vonnahme, D. C. Adams, G. P. Lardy, and R. N Funston. 2007. Effects of
dam nutrition on growth and reproductive performance of heifer calves. J. Anim. Sci.
85:841-847.
6Funston, R. N., J. L. Martin, D. C. Adams, and D. M. Larson. 2010b. Winter grazing system
and supplementation of beef cows during late gestation influence heifer progeny. J. Anim.
Sci. 88: 4094-4101.
7Underwood, K. R., J. F. Tong, P. L. Price, A. J. Roberts, E. E. Grings, B. W. Hess, W. J.
Means, and M. Du. 2010. Nutrition during mid to late gestation affects growth, adipose
tissue deposition and tenderness in cross-bred beef steers. Meat Sci. 86:588-593.
8Mulliniks, J. T., S. H. Cox, S. L. Ivey, C. P. Mathis, J. E. Sawyer, and M. K. Petersen. 2008.
Cow nutrition impacts feedlot pull rate. Proc. West. Sec. Am. Soc. Anim. Sci. 59:91-94.
9Larson, D. M., J. L. Martin, D. C. Adams, and R. N. Funston. 2009. Winter grazing system and
supplementation during late gestation influence performance of beef cows and steer
progeny. J. Anim. Sci. 87:1147-1155.
