Dynamics of culling risk with disposal codes reported by Dairy Herd Improvement dairy herds

Bascom, 1998, A summary of the reasons why farmers cull cows, J. Dairy Sci., 81, 2299, 10.3168/jds.S0022-0302(98)75810-2 Dechow, 2008, Mortality, culling by sixty days in milk, and production profiles in high- and low-survival Pennsylvania herds, J. Dairy Sci., 91, 4630, 10.3168/jds.2008-1337 Dematawewa, 1998, Genetic and phenotypic parameters for 305-day yield, fertility, and survival in Holsteins, J. Dairy Sci., 81, 2700, 10.3168/jds.S0022-0302(98)75827-8 2004 Esslemont, 1997, Culling in 50 dairy herds in England, Vet. Rec., 140, 36, 10.1136/vr.140.2.36 Fetrow, 2006, Invited review: Culling: Nomenclature, definitions, and recommendations, J. Dairy Sci., 89, 1896, 10.3168/jds.S0022-0302(06)72257-3 Goff, 1997, Physiological changes at parturition and their relationship to metabolic disorders, J. Dairy Sci., 80, 1260, 10.3168/jds.S0022-0302(97)76055-7 Hadley, 2006, Dairy cattle culling patterns, explanations, and implications, J. Dairy Sci., 89, 2286, 10.3168/jds.S0022-0302(06)72300-1 Hare, 2006, Survival rates and productive herd life of dairy cattle in the United States, J. Dairy Sci., 89, 3713, 10.3168/jds.S0022-0302(06)72412-2 McConnel, 2008, Evaluation of factors associated with increased dairy cow mortality on United States dairy operations, J. Dairy Sci., 91, 1423, 10.3168/jds.2007-0440 Milian-Suazo, 1988, Descriptive epidemiology of culling in dairy cows from 34 herds in New York State, Prev. Vet. Med., 6, 243, 10.1016/0167-5877(88)90036-0 Milian-Suazo, 1989, Risk factors for reason-specific culling of dairy cows, Prev. Vet. Med., 7, 19, 10.1016/0167-5877(89)90032-9 Miller, 2008, Death losses for lactating cows in herds enrolled in dairy herd improvement test plans, J. Dairy Sci., 91, 3710, 10.3168/jds.2007-0943 Pursley, 1998, Effect of time of artificial insemination on pregnancy rates, calving rates, pregnancy loss, and gender ratio after synchronization of ovulation in lactating dairy cows, J. Dairy Sci., 181, 2139, 10.3168/jds.S0022-0302(98)75790-X Rajala-Schultz, 1999, Culling of dairy cows. Part III. Effect of diseases, pregnancy status and milk yield on culling in Finnish Ayrshire cows, Prev. Vet. Med., 41, 295, 10.1016/S0167-5877(99)00047-1 Rogers, 1988, Influence of production and prices on optimal culling rates and annualized net revenue, J. Dairy Sci., 71, 3453, 10.3168/jds.S0022-0302(88)79951-8 Schneider, 2007, The effect of veterinary-treated clinical mastitis and pregnancy status on culling in Swedish dairy cows, Prev. Vet. Med., 80, 179, 10.1016/j.prevetmed.2007.02.006 Scott, 1994, The economic advantage of longevity in the dairy cow, J. Agric. Econ., 45, 113, 10.1111/j.1477-9552.1994.tb00382.x Sewalem, 2008, Relationship between reproduction traits and functional longevity in Canadian dairy cattle, J. Dairy Sci., 91, 1660, 10.3168/jds.2007-0178 Smith, 2000, Effect of region, herd size, and milk production on reasons cows leave the herd, J. Dairy Sci., 83, 2980, 10.3168/jds.S0022-0302(00)75198-8 Thomsen, 2004, Mortality (including euthanasia) among Danish dairy cows (1990–2001), Prev. Vet. Med., 62, 19, 10.1016/j.prevetmed.2003.09.002 van Arendonk, 1985, Studies on the replacement policies in dairy cattle. III. Influence of variation in reproduction and production, Livest. Prod. Sci., 13, 333, 10.1016/0301-6226(85)90025-9 Van Vleck, 1972, Association of type traits with reasons for disposal, J. Dairy Sci., 55, 1698, 10.3168/jds.S0022-0302(72)85747-3 Vitali, 2009, Seasonal pattern of mortality and relationships between mortality and temperature-humidity index in dairy cows, J. Dairy Sci., 92, 3781, 10.3168/jds.2009-2127 Weigel, 2003, Investigation of factors affecting voluntary and involuntary culling in expanding dairy herds in Wisconsin using survival analysis, J. Dairy Sci., 86, 1482, 10.3168/jds.S0022-0302(03)73733-3