Relationship between Early Postpartum Blood Composition and Reproductive Performance in Dairy Cattle

摘要: Blood samples were collected over 1 yr from 115 postpartum Holstein cows to determine the relationship between blood composition and reproductive performance. each cow at 14 21 days (sample 1) 38 45 2) postpartum. These analyzed for packed cell volume, hemoglobin, total protein, calcium, phosphorus, magnesium, copper, zinc, selenium. varied little with lactation number season, relationships not consistent two collection periods. Hemoglobin, protein zinc associated negatively calcium magnesium positively least one measure of milk yield. None components examined periods had a The most important was positive selenium concentration first period services per conception open.