2Madhumeet S, Satish K, Shweta S. Study on the clinical efficacy of ciprofloxacin administered through intrauterine route in repeat breeder cows suffering from endometritis in Himachal Pradesh [J]. Intas Polivet,2004,5(2) :209-210.
3Sheldon I M, Noakes D E, Rycroft A N, et al. Effect of intrauterine administration of oestradiol on postpartum uterinebacterial infection in cattle[J]. Animal Reproduction Science, 2004,81 (1-2):13-23.
4BERRY D P,LEE J M,MACDONALD K A,et al. Body con- dition score and body weight effects on dystocia and stillbirths and consequent effects on postcalving performance [J]. Journal of Dairy Science,2007,90(9) :4201-4211.
5HANSEN M,MADSEN P,JENSEN J J,et al. Genetic parame- ters of postnatal mortality in danish holstein calves[J]. Journal of Dairy Science,2003,86(5) : 1807-1817.
6THOMASEN J. Quantitative trait loci affecting calving traits in Danish Holstein cattle [J ]. Journal of Dairy Science, 2008,91 (5) : 2098-2105.
7MEE J F. Prevalence and risk factors for dystocia in dairy cattle : A review [ J ]. The Veterinary Journal, 2008,176 ( 1 ) :93- 101.
8JOHANSON J M ,BERGER P J. Birth weight as a predictor of calving ease and perinatal mortality in holstein cattle[J]. Jour- nal of Dairy Science, 2003,86 ( 11 ) : 3745-3755.
9BICALHO R C, GALVAO K N, CHEONG S H, et al. Ef- fect of stillbirths on dam survival and reproduction perfor- mance in holstein dairy cows [J]. Journal of Dairy Science, 2007, 90(6): 2797-2803.
10MEYER C L, BERGER P J, KOEHLER K J, et al. Pheno- typic trends in incidence of stillbirth for Holsteins in the U- nited States [J]. Journal of Dairy Science,2001,841 (2): 515-523.
