Odani studied military science under Hirayama Shiryū, took up Jikishinkage-ryū under Danno Genshin (真帆斎 Shinpansai), and was also accomplished in Hōzōin-ryū sōjutsu and Yoshida-ryū kyūjutsu.
Odani’s military science came from Hirayama Shiryū (平山行蔵 / 子竜), at whose Heigen Sōro academy he was a live-in pupil.
Naganuma-ryū (長沼流). The kotobank biography of Hirayama records his two specialties separately: he was especially accomplished in military science (Naganuma-ryū) and in kenjutsu (Shinkan-ryū). The sword side was distinct — he studied Shinkan-ryū (真貫流) under Yamada Shōsai (Mohei), founded his own Chūkō Shinkan-ryū, and later renamed it Kōbu Jitsuyō-ryū (講武実用流), the composite system he’s usually remembered for. So the military-science tradition Odani absorbed as a live-in pupil at the Heigen Sōro was Naganuma-ryū; his sword was a separate matter, taken in Jikishinkage-ryū under Danno, not from Hirayama’s Shinkan line.
One disambiguation: this 長沼流 is the heigaku house in the Naganuma Tansai (長沼澹斎) line and has nothing to do with the Naganuma-ha (長沼派) of Jikishinkage-ryū kenjutsu.
Odani’s own side: the sources cast him as an uchi-deshi whose eyes were “opened to practical martiality” under Hirayama rather than recording a formal Naganuma-ryū licence, so the safe formulation is that his military science derived from Hirayama’s Naganuma-ryū — not that he held a menkyo in it.
Totsuka-ha Yōshin-ryū was the Numazu domain’s jūjutsu — Totsuka Hikosuke Hidetoshi served the Mizuno house of Numazu as jūjutsu shihan and is called the reviver of early-modern randori — and Kashiwazaki was born in Numazu castle, trained under Totsuka, became the domain’s shihan-yaku, and served as Totsuka’s teaching proxy at the Kōbusho from 1853, exactly the man to carry it in. The Yōshin Ko-ryū account frames it as student-driven: dozens of Odani’s swordsmen who wanted jūjutsu training requested instruction from Kashiwazaki, and Aizawa taught the large group with him at the Odani dōjō — and the names listed alongside Sakakibara include Amano Shōzō, Danno Gennoshin, Kikuchi Tamenosuke, Chūjō, and Mitsuhashi.
The Chūjō there is the future Seieitai head — so the Totsuka-ha Yōshin-ryū you’d attributed to him, the same line Matsuoka carried into Shindō Yōshin-ryū, was picked up at the Odani dōjō rather than separately. The Jikishinkage-ryū dōjō was, in other words, a node of Totsuka-ha Yōshin-ryū transmission, sword and jūjutsu running side by side under one roof — the institutional precedent behind the whole Yōshin-ryū-as-the-sword’s-complement pattern we traced through Matsuoka and Nakayama. As a bonus, the same account has Aizawa regularly sparring at the Odani dōjō with Iikubo Tsunetoshi, Kanō Jigorō’s Kitō-ryū teacher — so the jūdō-genesis world brushes against this room too.
Odani is recorded as fully proficient — he mastered Hōzōin-ryū sōjutsu (宝蔵院流槍術; Hōzōin-ryū spear art) and Yoshida-ryū archery in addition to his Jikishinkage-ryū kenjutsu and the military science from Hirayama, Odani broke the Jikishinkage-ryū taboo on inter-school matches and actively sought them out, so spear was present at the dōjō as something his swordsmen crossed blades against — the same cross-discipline sparring that later produced the celebrated sword-versus-spear bout between Sakakibara and Takahashi Deishū at the 1860 Kōbusho opening. And spear was formally taught where Odani and Sakakibara actually worked, since the Kōbusho ran a separate sōjutsu department — just not, on the record, at the private dōjō.
