Which of the following best describes the reproductive cycle of swine?

The reproductive cycle of swine is best described by including the key physiological and behavioral stages that occur from the mating process through to the care of piglets. Estrus, or heat, is the period when the female swine (sow) is receptive to mating. Following this, mating occurs, leading to gestation, which is the period of development of the embryos in the sow's uterus.

After gestation, farrowing occurs, which is the process of giving birth to piglets. Once the piglets are born, the sow enters the lactation stage, during which she nurses and cares for her piglets. This comprehensive view captures the essential and progressive steps of swine reproduction, highlighting the biological processes critical for the successful rearing of pigs.

The other options do not encapsulate the entirety of the reproductive cycle. For instance, some mention only specific aspects like gestation and weaning or focus on other non-reproductive events such as breeding and slaughter or pregnancy and market readiness, missing key stages like estrus, mating, and lactation which are vital to understanding the whole reproductive cycle.