title: Effects of feeding ratio of beet pulp to alfalfa hay or grass hay on ruminal mat characteristics and chewing activity in Holstein dry cows.
abstract: The influence of the feeding ratio of a non-forage fiber source and hay on ruminal mat characteristics and chewing activity was evaluated in dairy dry cows. Cows were fed four different diets: the ratios of alfalfa hay (AH) to beet pulp (BP) were 8:2 (dry matter basis, A8B2) and 2:8 (A2B8), and those of grass hay (GH) to BP were 8:2 (G8B2) and 2:8 (G2B8). Total eating time was decreased with increasing BP content (P < 0.01). Total rumination time for AH was shorter than that for GH (P < 0.01), and it decreased with increasing BP content (P < 0.01). The ruminal mat was detected by using a penetration resistance test of the rumen digesta. Penetration resistance value (PRV) of ruminal mat was highest with the G8B2 diet and PRV decreased with increasing BP content (P < 0.05) and feeding AH (P < 0.05). Thickness of the ruminal mat was greater for increasing BP content (P < 0.05). Simple linear regression of ruminal mat PRV on total rumination time resulted in a high positive correlation (r = 0.744; P < 0.001; n = 16). The results demonstrated that increasing the PRV of the ruminal mat stimulated rumination activity and a ruminal mat could be formed, although it was soft even when cows were offered a large quantity of BP.
authors.affiliation: Research farm, Rakuno Gakuen University, Ebetsu, Japan. izmken@rakuno.ac.jp
authors.forename: Kenichi
authors.initials: K
authors.lastname: Izumi
authors.forename: Chigusa
authors.initials: C
authors.lastname: Unno
mesh_terms: D000821:Animal Feed; D000818:Animals; D027461:Beta vulgaris; D002417:Cattle / Q000502:physiology*; D004032:Diet / Q000662:veterinary*; D008409:Mastication; D012417:Rumen / Q000502:physiology*