Complex sentence: A gene also exists in the breed called the Thoka gene, and ewes carrying it have been known to give birth to triplets, quadruplets, quintuplets, and even sextuplets on occasion.
Split into simpler sentences: A gene also exists in the breed called the Thoka gene. Ewes that carry the gene have been known to give birth to triplets, quadruplets, quintuplets, and even sextuplets on occasion.