Influence of sorghum grain processing on performance of lactating dairy cows

Oliveira, J.S.; Huber, J.T.; Ben-Ghedalia, D.; Swingle, R.S.; Theurer, C.B.; Pessarakli, M.

Influence of sorghum grain processing on performance of lactating dairy cows

1993

Thirty-six lactating Holstein cows (80 DIM) were divided into four groups to compare steam-rolled corn with a density of 489 g/L, steam-flaked sorghum grain (360 g/L), dry-rolled sorghum grain (643 g/L), and an equal mixture of dry-rolled and steam-flaked sorghum grain. Each grain treatment constituted 42% of the TMR. A 14-d pretreatment period was used to allot cows to treatment and to adjust treatment means by covariance analysis. Treatment was for 80 d and included a 14-d digestibility trial using Cr2O3 as a marker. Intake of DM was higher for mixed than for flaked sorghum. Milk yield, FCM yield, and milk fat percentage were not altered by treatment, but cows fed steam-flaked sorghum had higher percentages of protein, lactose, and SNF in milk and greater milk protein yield than those fed dryrolled sorghum. Percentages of milk lactose and SNF were greater for cows fed flaked sorghum than for those fed steamrolled corn or the sorghum mixture. Digestibility of OM was higher for flaked sorghum than for steam-rolled corn or rolled sorghum, and digestibilities of CP and NDF were highest for dry-rolled sorghum. Total tract starch digestibility was lowest for cows fed dry-rolled sorghum (70%), highest (92%) for those fed steam-flaked sorghum, and intermediate (82%) for those fed rolled corn and the sorghum mix. Milk yield for cows fed steam-flaked sorghum grain was equal to or superior to that of cows fed steamrolled corn. Steam flaking of sorghum grain markedly increased starch digestibility and percentage milk protein compared with dry rolling.

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