On dairy herd culling and reproduction problems
2001
Suurmaa, A. | Jaerv, P. | Kaart, T. (Estonian Agricultural Univ., Tartu (Estonia))
The following conclusions and proposals from the results can be drawn: In case the high age at first calving (29 months) and short age of cows in the herds (4 years and 9 months), their productive age was less than 3 years (average 2.5 lactations), which is too short and is not economical. Due to the high culling (percentage) from herds by reasons of diseases and infertility, the dairy cattle management must be improved - feeding and keeping; milking technique and hygiene; veterinary service. It is possible to prolongat the productive age of cows. The raising of replacement cattle must be carried out with such growth intensity, which ensures early calving of heifers and maximum (lifetime) milk productivity of cows. The optimum growth intensity would be 700-800 g/day, age at first calving 24-26 months and body weight 545-565 kg. Then the first gestation (unigravida) must carried out at the age of 15 to 17 months, at the body weight of 355-375 kg respectively. By the results of previous studies and the data found in literature, the high growth rate of heifers in the rearing period (over g/day) may cause the decrease in milk yield of cows in the future
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Эту запись предоставил Estonian University of Life Sciences