Peanut Skins as a Feed Ingredient for Lactating Dairy Cows

¹ Department of Animal and Dairy Science, University of Georgia, Coastal Plain Station, Tifton 31793-0748

Twenty lactating Jersey cows were offered a TMR containing 0, 8, 16, or 24% peanut skins (testa) to determine the effect of peanut skins and their tannin component on cow performance. Increased percentage of peanut skins in the diet increased DMI and milk and FCM yields quadratically and increased both milk and FCM per DMI linearly. Cows offered the 8% peanut skin diet had the highest DMI, but milk and FCM yields were highest for cows fed the 8 and 16% peanut skin diets. Milk yield was lower for cows fed the 24% versus 8 and 16% peanut skin diets but was greater than controls. Milk fat percentage improved quadratically, but milk protein percentage declined linearly as peanut skin content of the diet increased. Ruminal NH₃ declined linearly as dietary peanut skin content increased. Digestibility of CP, serum urea N, and urinary N to creatinine ratio also declined linearly with increasing dietary peanut skins, indicating that indigestible tannin-protein complexes were formed that reduced protein availability. Peanut skins can be used in diets for lactating cows; however, based on effects on protein metabolism, they should be limited to about 16% of the diet, and diets should exceed the recommended minimum CP content.

Key Words: peanut skins in diet • tannins • lactation • testa

Submitted on June 8, 1992
Accepted on September 25, 1992