References

Anonymous, 2003. Genetic selection and crossbreeding to enhance reproduction and survival of dairy cattle. http://www.reeis.usda.gov/web/crisprojectpages/194420.html.

Arthur, G., D. Noakes, H. Pearson and T. Parkinson, 2001. Veterinary Reproduction and Obstetrics. 8th Edn., Saunders, London, England, pp: 520.

Caraviello, D.Z., K.A. Weigel, P.M. Fricke, M.C. Wiltbank and M.J., Florent et al., 2006. Survey of management practices on reproductive performance of dairy cattle on large us commercial farms. J. Dairy Sci., 89: 4723-4735.
PubMed  |  

Cleves, M., W. Gould, R. Gutierrez and Y. Marchenko, 2008. An Introduction to Survival Analysis using Stata. 2nd Edn., Stata Press, Texas, USA., pp: 372.

Collett, D., 2003. Modelling Survival Data in Medical Research. 2nd Edn., Chapman and Hall, London, pp: 251-271.

DeJarnette, J., C. Sattler, C. Marshall and R. Nebel, 2007. Voluntary waiting period management practices in dairy herds participating in a progeny test program. J. Dairy Sci., 90: 1073-1079.
PubMed  |  

Dohoo, I., E. Tillard, H. Stryhn and B. Faye, 2001. The use of multilevel models to evaluate sources of variation in reproductive performance in dairy cattle in Reunion Island. Preventive Vet. Med., 50: 127-144.

Eicker, S.W., Y.T. Grohn and J.A. Hertl, 1996. The association between cumulative milk yield, days open and days to first breeding in New York Holstein cows. J. Dairy Sci., 79: 235-241.
CrossRef  |  PubMed  |  

Elwood, J., 1998. Critical Appraisal of Epidemiological Studies and Clinical Trials. 2nd Edn., Oxford University Press, London, pp: 323-339.

Farin, P., B. Slenninq, M. Correa and J. Britt, 1994. Effects of calving season and milk yield on pregnancy risk and income in North Carolina Holstein cows. J. Dairy Sci., 77: 1848-1855.
PubMed  |  

Frei, C., P. Frei, K. Stark, D. Pfeiffer and U. Kihm, 1997. The production system and disease incidence in a national random longitudinal study of Swiss dairy herds. Preventive Vet. Med., 32: 1-21.
PubMed  |  

Gutierrez, R.G., 2002. Parametric frailty and shared frailty survival models. Stata J., 2: 22-44.
Direct Link  |  

Harman, J., G. Casella and Y. Grohn, 1996. The application of event-time regression techniques to the study of dairy cow interval-to-conception. Preventive Vet. Med., 26: 263-274.

Harman, J., Y. Grohn, H. Erb and G. Casella, 1996. Event-time analysis of the effect of season of parturition, parity and concurrent disease on parturition to conception interval in dairy cows. Am. J. Vet. Res., 57: 640-645.
PubMed  |  

Kaneene, J. and H. Hurd, 1990. The national animal health monitoring system in michigan. I: Design, data and frequencies of selected dairy cattle diseases. Prev. Vet. Med., 8: 103-114.

Klein, J.P. and M.L. Moeschberger, 2003. Survival Analysis: Techniques for Censored and Truncated Data. Springer Verlag, New York, USA., pp: 243-325.

Kleinbaum, D. and M. Klein, 2005. Survival Analysis. 2nd Edn., Springer Verlag, New York, USA., pp: 83-225.

Lee, L., J. Ferguson and D. Galligan, 1989. Effect of disease on days open assessed by survival analysis. J. Dairy Sci., 72: 1020-1026.
PubMed  |  

Loeffler, S., M.J. de Vries and Y.H. Schukken, 1999. The effects of time of disease occurrence, milk yield and body condition on fertility of dairy cows. J. Dairy Sci., 82: 2589-2604.
CrossRef  |  PubMed  |  

Maizon, D.O., P.A. Oltenacu, Y.T. Grohn, R.L. Strawderman and U. Emanuelson, 2004. Effects of diseases on reproductive performance in Swedish red and white dairy cattle. Prev. Vet. Med., 66: 113-126.

Meadows, C., R. Rajala-Schultz, G. Frazer, R. Meirin and K. Hoblet, 2006. Evaluation of a contract breeding management program in selected Ohio dairy herds with event-time analysis I. Cox proportional hazards models. Preventive Vet. Med., 77: 145-160.

Meadows, C., R. Rajala-Schultz, G. Frazer, R. Meiring and K. Hoblet, 2007. Evaluation of a contract breeding management program in selected Ohio dairy herds with event-time analysis II. Parametric frailty models. Preventive Vet. Med., 80: 89-102.

Melendez, P. and P. Pinedo, 2007. The association between reproductive performance and milk yield in chilean holstein cattle. J. Dairy Sci., 90: 184-192.
Direct Link  |  

Radostitis, O. and D. Blood, 2001. Herd Health Food Animal Production Medicine. 3rd Edn., Saunders, Philadelphia, Pennsylvania, USA., pp: 278.

Rajala-Schultz, P. and G. Frazer, 2003. Reproductive performance in Ohio dairy herds in the 1990s. Anim. Reprod. Sci., 76: 127-142.
PubMed  |  

Schneider, M.P., E. Strandberg, V. Ducrocq and A. Roth, 2005. Survival analysis applied to genetic evaluation for female fertility in dairy cattle. J. Dairy Sci., 88: 2253-2259.
PubMed  |  

Schneider, M.P., E. Strandberg, V. Ducrocq and A. Roth, 2006. Genetic evaluation of the interval from 1st to last insemination with survival analysis and linear models. J. Dairy Sci., 89: 4903-4906.
PubMed  |  

Schnier, C., S. Hielm and H. Saloniemi, 2004. Comparison of the breeding performance of cows in cold and warm loose-housing systems in Finland. Preventive Vet. Med., 62: 135-151.

Silva, H., C. Wilcox, W. Thatcher, R. Becker and D. Morse, 1992. Factors affecting days open, gestation length and calving interval in Florida dairy cattle. J. Dairy Sci., 75: 288-293.
PubMed  |  

Stevenson, M., 2000. Disease incidence in dairy herds in the southern highlands district of New South Wales, Australia. Preventive Vet. Med., 43: 1-11.