Analysis of the economically optimal voluntary waiting period for first insemination
- 1 August 2011
- journal article
- Published by American Dairy Science Association in Journal of Dairy Science
- Vol. 94 (8), 3811-3823
- https://doi.org/10.3168/jds.2010-3790
Abstract
The voluntary waiting period (VWP) is defined as the time between parturition and the time at which the cow is first eligible for insemination. Determining the optimal VWP from field data is difficult and unlikely to happen. Therefore, a Monte-Carlo dynamic-stochastic simulation model was created to calculate the economic effects of different VWP. The model is dynamic and uses time steps of 1 wk to simulate the reproductive cycle (ovulation, estrous detection, and conception), the occurrence of postpartum disorders, and the lactation curve. Inputs of the model were chosen to reflect the situation of Dutch dairy cows. In the model, we initially created a cow of a randomly selected breed, parity, month of calving, calf status of last calving, and expected 305-d milk yield. The randomly varied variables were based upon relevant distributions and adjusted for cow statuses. The lactation curve was modeled by Wood's function. The economic input values in the analysis included: cost of milk production (€0.07 to €0.20 per kg), calf price (€35 to €150 per calf), AI cost (€7 to €24 per AI), calving management cost (€137 to €167 per calving), and culling cost, expressed as the retention pay-off (€118 to €1,117). A partial budget approach was used to calculate the economic effect of varying the VWP from 7 to 15 wk postpartum, using a VWP of 6 wk as reference. Per iteration, the VWP with either the lowest economic loss or the maximum profit was determined as the optimal VWP. The optimal VWP of most cows (90%) was less than 10 wk. On average, every VWP longer than 6 wk gave economic losses. Longer VWP were in particular optimal for the first parity of breeds other than Holstein-Friesian, cows calving in winter with low milk production, high milk persistency, delayed peak milk yield time, a delayed time of first ovulation, or occurrence of a postpartum disorder, and while costs of milk production are low and costs for AI are high.Keywords
This publication has 30 references indexed in Scilit:
- Breed and Parity Effects on Energy Balance Profiles Through Lactation: Evidence of Genetically Driven Body Energy ChangeJournal of Dairy Science, 2007
- Economic effects of bovine mastitis and mastitis management: A reviewVeterinary Quarterly, 2007
- Economic Comparison of Timed Artificial Insemination and Exogenous Progesterone as Treatments for Ovarian CystsJournal of Dairy Science, 2006
- An Economic Spreadsheet Model to Determine Optimal Breeding and Replacement Decisions for Dairy CattleJournal of Dairy Science, 2004
- Association of cow and quarter-level factors at drying-off with new intramammary infections during the dry periodPreventive Veterinary Medicine, 2004
- The Effect of Extended Calving Intervals in High Lactating Cows on Milk Production and ProfitabilityJournal of Dairy Science, 2001
- Simulated effects on dairy cattle health of extending the voluntary waiting period with recombinant bovine somatotropinPreventive Veterinary Medicine, 2000
- Effects of milk yield, and calving to first service interval, in determining herd fertility in dairy cowsAnimal Reproduction Science, 1996
- Interrelationships Between Energy Balance and Postpartum Reproductive Function in Dairy CattleJournal of Dairy Science, 1989
- Economic aspects of reproductive failure in dairy cattle. I. Financial loss at farm levelPreventive Veterinary Medicine, 1985