[3] In the pigs, deficiency of the mitochondrial cytochrome P450 enzyme 17α-hydroxylase (CYP17A1) causes very low 17α-Hydroxypregnenolone levels, leading to pseudohermaphroditism.
Intersex pigs are kept for use in Nimangki grade-taking ceremonies at Patani village on the northwestern coast of Espiritu Santo.
Some intersex pigs are kept on Gaua and northeastern Ambae islands, although they are not as prevalent compared to the early 20th century.
[6] John R. Baker (1928) reported large numbers of intersex pigs in Espiritu Santo, where he reported to have seen "no fewer than 125 intersexes in one single day at Hog Harbour" during an event when younger and older pigs were brought together from different islands for trading.
He also received reports that such pigs were present on the islands of Gaua, Vanua Lava, Mota, Ambae, Ambrym (not in large numbers), and Tongoa.