Increased calf production in cattle selected for twin ovulations.

  title={Increased calf production in cattle selected for twin ovulations.},
  author={Sherrill E. Echternkamp and Richard Mark Thallman and Robert A. Cushman and Mark F. Allan and Keith E. Gregory},
  journal={Journal of animal science},
  volume={85 12},
The effects of increasing fetal numbers and their distribution between the left and right uterine horns on calf survival, calf BW at birth and weaning, gestation length, dystocia, and calf sex ratio were evaluated for single (n = 1,587), twin (n = 2,440), and triplet calves (n = 147) born to primiparous and multiparous females in the Twinner population at the US Meat Animal Research Center between 1994 and 2004. Cattle were distributed equally between the spring and fall breeding seasons. Fetal… 

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