The aim of this study was to evaluate the various alternations between long and short days of sunlight in an attempt to optimise the production of semen collected for artificial insemination (AI) under field conditions. The results suggest that alternation between long days and short days allowed for the production of AI doses all year round in large scale under field conditions. The alternation 45 LD / 45 SD seems to be the better treatment to optimise the production of AI doses. Under these conditions the production of AI doses was not influenced by the rhythm of collection. More investigations are necessary to optimise the rhythm of weekly collection.