حسین پور مشهدی، م.، 1387. ارزیابی ژنتیکی صفات تولید شیر در گاوهای هلشتاین ایران. سومین کنگره علوم دامی کشور، 839-841.
زمانی دهکردی، پ.، وطن خواه، م. و فاضلی، م. ه. 1389. مطالعه عملکرد برخی صفات تولیدی و تولیدمثلی گاوهای آمیخته در استان چهارمحال و بختیاری. چهارمین کنگره علوم دامی کشور، 2777-2779.
فرجی آروق، ه.، طهمورث پور، م.، نصرتی، م. و صیادنژاد م.ب. 1389. ارزیابی ژنتیکی صفات تولید مثلی گاوهای هلشتاین استان خراسان رضوی با استفاده از آنالیز چند متغیره. دومین کنگره علوم دامی کشور. 2997-3001.
فرهنگ فر، ه. و نعیمی پور ح. 1386. برآورد پارامترهای فنوتیپی و ژنتیکی صفات تولید و تولیدمثل در نژاد گاو هلشتاین ایران. علوم و فنون کشاورزی و منابع طبیعی. شماره اول.
هنرور، م.، مرادی شهربابک، م. و میرایی آشتیانی، ر. 1383. بررسی پارامترهای صفات تولیدمثلی و رابطه آن با تولید شیر در گاوهای هلشتاین ایران. اولین کنگره علوم دامی. 685-688.
Ben gara, A., R. Bouraoui, B. Rekeik, H. Hammami and H. Rouissi. 2009. optimal age at first calving for improved milk yield and length of productive life in Tunisian Holstein cows. Ameuras. J. Agron. 2 (3): 162-167.
Bewley, J., R. W. Palmer, and D. B. Jackson-Smith. 2001. Modeling milk production and labor efficiency in modernized Wisconsin dairy herds. J. Dairy Sci. 84:705–716.
Cienfuegos-Rivas, E. G., P. A. Oltenacu, R. W. Blake, and H. Castillo-Juarez. 2006. Fertility responses of Mexican Holstein cows to US sire selection. J. Dairy Sci. 89:2755–2760.
Cole, J. B., and D. J. Null.2010. Age at first calving in US. Holsteins. J. Dairy. Sci. Accepted.
Erb, H. N., R. D. Smith, P. A. Oltenacu, C. L. Guard, R. B. Hillman,P. A. Powers, M. C. Smith, and M. E. White. 1985. Path modelof reproductive disorders and performance, milk fever, mastitis, milk yield, and culling in Holstein cows. J. Dairy Sci. 68:3337–3349.
Gardner, R. W., L. W. Smith, and R. L. Park. 1988. Feeding and management of dairy heifers for optimal lifetime productivity. J. Dairy Sci. 71:996–999.
Gonzales-Recio, O.P., Alenda, R., Chang Y.M., Weigel, K.A. and Gianola, D. 2006. Selection for female fertility using censored fertility traits and investigation of the relationship with milk production. J. Dairy. Sci. 89: 4438-4444.
Hare, E., Norman H. D. and J. R. Wright. 2006. Trends in Calving Ages and Calving Intervals for Dairy Cattle Breeds in the United States. J. Dairy Sci. 89:365–370.
Heinrichs, A. J. 1993. Raising dairy replacement to meet the need of the 21st century. J. Dairy Sci. 76:3179–3187.
Heinrichs, A. J., S. J. Wells, H. S. Hurd, G. W. Hill, and D. A. Dargatz. 1994. The national dairy heifers evaluation project: A profile of heifer management practices in United States. J. Dairy Sci. 77:1548–1555.
Hodel, F., J. Moll, and N. Kuenzi. 1995. Analysis of fertility in Swiss Simmental cattle—Genetic and environmental effects on female fertility. Livest. Prod. Sci. 41:95–103.
Hoffman, P. C. 1997. Optimum body size of Holstein replacement heifers. J. Anim. Sci. 75:836–845.
Hoffman, P. C., N. M. Brehm, S. G. Price, and A. Prill-Adams. 1996. Effect of accelerated postpubertal growth and early calving in lactation performance of primiparous Holstein heifer. J. Dairy Sci. 79:2024–2031.
Losinger,W. C., and A. J. Heinrichs. 1996. Dairy operation management practices and herd milk production. J. Dairy Sci. 79:506–514.
Ma¨ntysaari, P., M. Ojala, and E. A. Ma¨ntysaari. 2002. Measures of before and after breeding daily gains of dairy replacement heifers and their relationship with first lactation milk production traits. Livest. Prod. Sci. 75:313–322.
Martinez, M. L., A. E. Freeman, and P. J. Berger. 1983. Genetic relationship between calf livability and calving difficulty of Holsteins. J. Dairy Sci. 66:1494–1502.
Montalda, H. H., H. Casillo-Juarez, M. Valencia-Posadas, E.G. 2010. Genetic and environmental parameters for milk production, udder health, and fertility traits in Mexican Holstein cows. J. Dairy. Sci. 93:2168-2175.
Moore, R. K., P. P. Kennedy, L. R. Schaeffer, and J. E. Moxley. 1991. Relationships between age and body weight at calving and production in first lactation Ayrshires and Holsteins. J. DairySci. 74:269–278.
Mourits, M. C. M., A. A. Dijkhuizen, R. B. M. Hurine, and D. T. Galligan. 1997. Technical and economic models to support heifer management decisions: basic concepts. J. Dairy Sci. 80:1406–1415.
Nilforooshan, M.A. and M.A. Edriss. 2004. Effect of Age at First Calving on Some Productive and Longevity Traits in Iranian Holsteins of the Isfahan Province. J. Dairy Sci. 87:2130–2135.
Ojango, J. M. K., and G. E. Pollott. 2001. Genetics of milk yield and fertility traits in Holstein-Friesian cattle on large-scale Kenyan farms. J. Anim. Sci. 79:1742–1750.
Pirlo, G., F. Miglior, and M. Speroni. 2000. Effect of age at first calving on production traits and on difference betweenmilk yield returns and rearing costs in Italian Holsteins. J. Dairy Sci. 83:603–608.
Razmkabir, M., Nejati-javeremi, A., Moradi-Shahre Babak, M., Rashidi, A. and Sayadnezhad, M.B. 2006. Estimation of genetic trends for production traits in Holstein cattle of Iran. 8th World Congress on Genetics Applied to livestock Production. Brazil.
Ruiz-Sa´nchez, R., R. W. Blake, H. M. A. Castro-Ga´mez, F. Sa´nchez, H. H. Montaldo, and H. Castillo-Jua´rez. Changes in the Association Between Milk yield and Age at First Calving in Holstein Cows with Herd Environment Level for Milk Yield. Dairy Sci. 90:4830–4834 doi:10.3168/jds.2007-0156.
Studer, E. 1998. A veterinary perspective of on-farm evaluation of nutrition and reproduction. J. Dairy Sci. 81:872–876.
Suzuki, M. 2006. Heritability of herd life and relationship between herd life and milk production, type and fertility traits of Holstein cows in Japan. Nihon Chikusan Gakkaiho. 77(1):9-15.
Thompson, J. R., E. J. Pollak, and P. L. Pelissier. 1983. Interrelationships of parturition problems, production of subsequent lactation, reproduction, and age at first calving. J. Dairy Sci. 66:1119–1127.
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