Effect of High Concentrate Corn Stalk Particle Size on Physical State and Production Performance of Lactating Dairy Cows

In order to realize the application of corn stalk in\r\ncow feed, we designed experiments to explore the effect of a certain proportion\r\nof corn stalk on the performance of lactating dairy cows. 9 multiparous\r\nmid-lactating cows were allocated at random to three groups, each containing 3\r\nintact cows. The trial consisted of three\r\nperiods and three dietary treatments with a 3 × 3 Latin square design. The diets were normal concentrats\r\nplus dried corn stalk chopped to 5 - 8 cm long (N), high concentrates\r\nplus dried corn stalks chopped to a length of approximately 5 - 8 cm by a mower\r\n(H) while the milled corn stalks were passed through a pulviser with a 2 cm\r\npore size (MH). Each cow was measured for dry matter intake (DMI), ruminal pH,\r\nrumen fermentation, selective feeding\r\nbehavior and production performance. The results showed that MH led to a\r\nsignificantly higher intake of DM, neutral detergent fiber (NDF), forage NDF\r\n(FNDF), acid detergent fiber (ADF), crude protein (CP) and organic matter (OM)\r\nthan N and H (P ity for the dietary\r\ncomponent. MH resulted in a significantly higher milk production (P P = 0.055). There were no significant differences in the milk components (P = 0.424) and lactose (P = 0.113) between cows fed N and MH.\r\nThe high-concentrates plus milled corn\r\nstalk diet can increase the milk yield under the premise of normal rumen\r\npH in dairy cows, thereby generating higher economic benefits. And milled corn\r\nstalk can effectively inhibit the cow’s selective eating of low-quality\r\nroughage.