yes splay leg is part of the pamimilay - this case can be remedied if mataas ang level ng choline sa diet (choline choride is the commercially available material to provide choline).
sa still birth and mummified mo... management can play a role. tulad ng stress sa paglilipat ng baboy or overfeeding so lumalaki ng husto ang piglets at birth. as a general thing, if you are not stressing out the sows and proper and feeding, then mycotoxin like zearalenone could be the culprit. adding a toxin binder in the diet will help reduce the case pero matagal ito umepekto (around 2-3 months) depending on challenge.
biotin deficiency naman ang normal cause ng nail damage (aside from FMD) kung nutritional. however, having a regularly wet flooring or nabababad sa tubig ang kuko nila can also trigger this.
kung commercial feed bigay mo... try to change brand.
if home mixed feeds yan, ano po ba ang vitamin at mineral premix brand that you use. we can probably modify the dosage to correc the issue/s.