When Rachel gave birth to Joseph, Jacob asked Laban to send him to his own country, along with his wives an children. All the days Jacob worked for the development of Laban and his family, but not developed anything for his own family and his children. Laban said i was blessed by the God because of you, i want to fix your salary the way you want. Then Jacob asked for cattle which are speckled and spotted as his salary. Then Jacob started feeding the cattle of Laban, and separated speckled and spotted cattle and kept them aside, from the day Jacob reached the agreement with Laban, all the cattle gave birth to strong, speckled and spotted. by the grace of God Jacob increased menservants, maidservant, cattle, camels and asses.
~ Genesis Chapter 28