ANSC 312 Lecture Notes - Lecture 18: Estrous Cycle, Ovulation, Obstructed Labour
15 Apr 2019
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Lecture 18 reproductive problems in dairy cattle possible. # days open = when the cows are not pregnant, farmers want them to be lower as. Parturition intervals are the time between the calving of one cow. Nutrition is very important to decrease the occurrence of metabolic diseases and the reproductive efficiency. Increased days open leads to increased calving interval. The proper time for one lactation is one year. The normal lactation is 305 days and than the cows are dried 60-80 days prior to calving. The average calving interval is 415 days according to holstein canada, so this is getting further from the optimal 12 months. Service per conception represents the number of time is required to inseminate the cows in order for her to get pregnant. Today, the average is about 4 services per conception. This is not because the fertility of cow is lower or because we are selecting for infertile cows.
