From "Le Marche e la Prima Guerra Mondiale".
Company (compagnia) 1915:
Comandante,
Plotone misto (HQ),
1-3 plotone.
5 officers, 250 other ranks. 4 animals.
Company 1918:
Comandante,
Plotone comando,
1-3 plotone,
Sezione pistole mitragliatrici (= 2 Fiat 1915).
4 officers, 169 other ranks.
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Battalion (Battaglione) 1915
Comando,
1-4 compagnia,
Sezione mitragliatrici (= 2 MG).
25 officers, 1068 other ranks. 33 animals, 12 carts (2-wheel), 5 bicycles.
Battalion (Battaglione) 1918
Comando,
1-3 compagnia,
Compagnia mitragliatrici Fiat (= 8 MG),
Compagnia zappatori (sappers),
Sezione lanciabombe "Stokes" (= 4 3-in. mortars).
22 officers, 780 other ranks. 35 animals, 16 carts (2-wheel), 5 bicycles.
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Regiment (Reggimento) 1915
Comando,
1-3 battaglione,
Unita di salmeria reggimentale (supply column).
81 officers, 3505 other ranks. 330 animals, 39 carts (2-wheel), 2 carts (4-wheel), 20 bicycles.
Regiment (Reggimento) 1918
Comando,
1-3 battaglione,
Unita di salmeria reggimentale (supply column).
81 officers, 2591 other ranks. 222 animals, 54 carts (2-wheel), 2 carts (4-wheel), 20 bicycles.
Note, that the book mentions also the following units created in the regiment during the war:
- plotone assalto,
- repato cannonicini 37-mm (4 infantry guns),
- sezione lanciafliamme (12 portable flame throwers).
It is unclear, where they were disbanded by 1918 or were supernumerary - i.e. not included in the TOE organization.
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Brigade (Brigata) 1915 - in Italian army this was the highest level of infantry organization.
Comando,
1-2 reggimento.
Brigade 1918
Comando,
1-2 reggimento,
1-2 Compagnia mitragliatrici.