Abstract #T157

# T157
Evaluation of seed corn hybrids to provide nutrients that are highly digestible for South Dakota livestock operations.
David P. Casper*1, Sara Sontag1, Laura McMartin1, William Weich1, Jonathan Kleinjan1, 1South Dakota State University, Brookings, SD.

South Dakota cropping operations are historically well known historically, as is the SD State University (SDSU) Crop Performance Testing (CPT) program, for focusing on grain production. Recent expansion of the SD dairy industry has created interest in selecting the right seed hybrid for either corn silage and/or grain production. A unique SDSU relationship developed to expand the CPT program to evaluate hybrids for forage production and quality. This information will be crucial for the Interstate-29 SD dairy industry to compete globally. In the 2013 growing season, 45 grain hybrids were evaluated for both corn silage and grain. Hybrids were planted in 4 row field test plots at the SDSU Volga research farm. Corn plants from the center rows were hand harvested at a min of 15 cm from the ground. The plants were weighed, chopped (chipper/shredder), inoculated with Silo King (0.55 kg/ton), packed in duplicate 18.9 L buckets, sealed, weighed, and allowed to ensile for >90 d at which time, buckets were weighed, opened, and samples submitted for measurement of nutrient concentrations and digestibility (Analab Inc.). In the 2014 growing season, 31 silage specific silage hybrids were evaluated. Procedures were the same, except buckets were opened at 60 and 90 d. In the 2013, the grain hybrids were drier at harvest (range: 28.7 – 56.5; mean = 39.1 ± 3.21% DM), compared with 2014 hybrids being wetter (range: 21.8 - 39.6: mean = 29.9 ± 2.62% DM). For the 2013, the hybrids varied in digestible DM (range: 60.6 – 74.3; mean = 69.8 ± 3.21% DM), while 2014 hybrids were (range: 65.4 – 72.5: mean = 69.6 ± 2.54%) were less variable. The 2014 DM silage yield (range: 18.4 - 23.8; mean = 20.2 ± 2.51 t/ha) varied dramatically, while digestible DM yield (range: 12.4 - 16.8; mean = 14.1 ± 2.02 t/ha) varied as well. Selecting the appropriate seed corn hybrid can improve corn silage yield and digestibility, thereby the right hybrid being able to meet a great percentgae of the nutrient requirements of the lactating dairy cow.

Key Words: hybrid, corn silage, forage