39
obtidos com o uso a campo de sêmen nacional e importado. Rev. Bras. Reprod. Anim.
(Suplemento), n.4, p.159-161, 1993.
PURSLEY, J.R., WILTBANK, M.C., STEVENSON, J.S. et al. Pregnancy rates per artificial
insemination for cows and heifers inseminated at a synchronized ovulation or synchronized estrus.
J. Dairy Sci., v.80, p.295-300, 1997.
RENQUIST, B.J.; OLTJEN, J.W.; SAINZ, R.D. et al. Relationship between body condition score and
production of multiparous beef cows. Livest. Sci., v.104, p.147-155, 2006.
REURINK, A.; DEN DAAS, J.H.G.; WILMINK J.B.M. Effects of AI sires and technicians on non-
return rates in the Netherlands. Liv. Prod. Sci., v.26, n.2, p.107-118, 1990.
RICHARDS, M.W.; SPITZER, J.C.; WARNER, M.B. Effect of varying levels of postpartum nutrition
and body condition at calving on subsequent reproductive performance in beef cattle. J. Anim.
Sci., v.62, p.300-306, 1986.
ROCHE, J.R.; DILLON, P.G.; STOCKDALE, C.R. et al. Relationships among international body
condition scoring systems. J. Dairy Sci., v.87, p.3076-3079, 2004.
RYCROFT, H.; BEAN, B. Factors influencing non-return rates data. Proc. 14
th
Tech. Conf. AI
Reprod. Natl. Assoc. Anim. Breed., Milwaukee, WI, p.43, 1992.
SAS – User’s guide: Stat. Version 8. Cary: SAS Institute, 1999.
SENGER, P.L. Fertility factors – which ones are really important? Proc. 6
th
West. Dairy Manag.
Conf. Reno, NV, p.89-106, 2003.
SENGER, P.L.; BECKER, W.C.; DAVIDGE, S.T. et al. Influence of cornual insemination on
conception rates in dairy cattle. J. Anim. Sci., v.66, p.3010-3016, 1988.
SENGER, P.L.; HILLERS, J.K.; MITCHELL, J.R. et al. Effects of serum treated semen, bulls and
herdsmen-inseminators on conception to first service in large commercial dairy herds. J. Dairy
Sci., v.67, p.686-692, 1984.
SHIVELY, T.E.; WILLIAMS, G.L. Patterns of tonic luteinizing hormone release and ovulation
frequency in suckled anestrous beef cows following varying intervals of temporary weaning.
Dom. Anim. End., v.6, p.379-387, 1989.
SHORT, R.E.; ADAMS, D.C. Nutritional and hormonal interrelationships in beef cattle reproduction.
Canad. J. Anim. Sci., v.68, p.29, 1988.
SIQUEIRA, L.C.; OLIVEIRA, J.F.C.; LOGUÉRCIO, R.S. et al. Sistemas de inseminação artificial em
dois dias de observação de estro ou em tempo fixo para vacas de corte amamentando. Ciência
Rural, v.38, p.411-415, 2008.
SMITH, M.F.; BURRELL, W.C.; SHIPP, L.D. et al. Hormonal treatments and use of calf removal in
postpartum beef cows. J. Anim. Sci., v.48, p.1285-1294, 1979.
SPRENGER, M.J.; DE JARNETTE, J.M.; MARSHALL, C.E. Conception rates of sequential
inseminations after batch-thawing multiple straws of semen: A professional technician case study.
J. Anim. Sci., v.79 (Suppl.1), p.253, 2001.
STEVENSON, J.S. Factors to improve pregnancy rates in lactating dairy cattle. In: CONGRESSO