Improving reproductive performance
A technique to measure the level of progesterone in blood or milk can be used to improve reproductive performance in livestock. Radioimmunoassay (RIA) uses the measurement of reproductive hormones to provide a better understanding of the reproductive physiology of farm animals: for instance, ovarian activity is revealed by monitoring progesterone levels. This information can then be used to calculate onset of puberty, resumption of ovulation after parturition, ovarian dysfunctions, time of oestrus and non pregnancy.
The measurement of progesterone in this way can be an important tool in the evaluation of intervention strategies such as in the monitoring of feed supplements (see Food for Humans, Feed for Animals), grassland management, calf rearing practices, hormonal treatments and artificial insemination programmes.
In Peru, the technique was successfully used to improve reproductive performance of dairy cows as part of a project supported by the FAO/IAEA Co-ordinated Research Programme and Technical Co-operation Project. The activities involved the introduction of Zebu x European crossbreeds through an artificial insemination programme and the use of cultivated pastures to improve nutrition and reproductive management practices. Sustainable milk production was established in the region by monitoring progesterone levels in the cows to reduce age at first calving, post-partum anoestrus period and calf mortality.
Similar examples of substantially improved reproductive and productive performance have been achieved in several other tropical countries.
