The information reproted below comes from a NE Beef Report Article and can be found at http://beef.unl.edu/beefreports/200901.shtml. A group of spring-calving cows were supplemented a protein cube while grazing corn stalk residue and there was a group of cows grazing corn stalk residue that was not supplemented. After corn stalk grazing, cows were managed together. Pre-calving weight and body condition were statistically different between the two groups in favor of the supplemented group of cows. Precalving body condition score for cows grazing corn stalks and supplemented was 5.3 and that for non-supplemented cows was 5.2, although these numbers are statistically different, they are likely not different biologically, meaning it would be difficult to say that any performance difference between the two groups is a result of differences in body condition; nor would you expect any differences in performance due to differences in body condition of the two groups. There was no difference in calf birth or weaning weight. Calving date, percentage of the cows calving the first 21 days of the calving season, nor milk production was different. Subsequent pregnancy rate was high for both groups (97% for supplemented and 95% for non-supplemented cows).

We have other data (2008 NE Beef Report http://beef.unl.edu/beefreports/200805.shtml) that suggests small difference in body condition for cows that were either supplemented or not supplemented while grazing corn stalk residue. However, there was no difference in reproductive performance between the supplemented and non-supplemented groups. In this study, cows were in good body condition (greater than BCS 5.0) when they went to stalks.

The fetal programming hypothesis states postnatal growth and physiology can be influenced by stimulus experienced in utero. Can the performance of calves be influenced by nutrition of the dam during late gestation? The study described above evaluated steer and heifer performance from supplemented and non-supplemented dams that were grazing corn stalk residue. Heifers from dams that were supplemented while grazing crop residue were younger when they reached puberty. Pregnancy rate tended to be greater for heifers from dams that were supplemented protein precalving compared to heifers whom dams were not supplemented. Pregnancy rates for heifers from dams that were grazing corn stalks and supplemented was 88% compared to 83% for heifers whom dams were not supplemented.

The performance of the steer mates to the heifers discussed above was also recorded. Carcass weight, backfat, ribeye area, and yield grade were not different between steers whom dams were supplemented compared to steers whom dams were not supplemented. Percentage of the steers grading USDA Low Choice or better was greater for steers from dams that were supplemented compared to steers from dams that were not supplemented, steers from dams that grazed corn residue and were supplemented (86%) compared to steers from dams that grazed corn residue and were non-supplemented (64%).

The point here is to not only evaluate the effect of the management strategy in regard to cow performance, but also how the management strategy may impact the performance of the calf that is being developed in the uterus. As with all management strategies, determine the economics and how they might effect profitability and use data to help determine differences that can be expected. These data were developed in using feed resources in Nebraska, visit with your beef specialist about how these concepts might fit the feed resources and supplementation strategies in your location.