▁Nor folk ▁Regiment ▁officers ▁Category : Ro yal ▁F lying ▁Corps ▁officers ▁Category : Ro yal ▁Air ▁Force ▁personnel ▁of ▁World ▁War ▁I ▁Category : B rit ish ▁World ▁War ▁I ▁flying ▁a ces <0x0A> </s> ▁Hel ig mos omo ides ▁poly gy rus , ▁previously ▁named ▁Nem atos pi roid es ▁dub ius , ▁is ▁a ▁naturally ▁occurr ing ▁int est inal ▁round w orm ▁of ▁rod ents . ▁It ▁belongs ▁to ▁the ▁family ▁Try ch ost rong yl idae , ▁and ▁male ▁and ▁female ▁w orm s ▁are ▁morph olog ically ▁distinguish able . ▁The ▁par as ite ▁has ▁a ▁direct ▁lif ecycle , ▁with ▁its ▁lar val ▁form ▁being ▁the ▁inf ect ive ▁stage . ▁H . ▁poly gy rus ▁has ▁the ▁ability ▁to ▁establish ▁chron ic ▁in fe ctions ▁in ▁rod ents ▁and ▁alter ▁host ▁imm une ▁responses . ▁This ▁n emat ode ▁is ▁widely ▁used ▁as ▁a ▁g astro int est inal ▁par as it ic ▁model ▁in ▁imm un ological , ▁ph arm ac ological , ▁and ▁to xic ological ▁studies . ▁ ▁L ifecycle ▁and ▁morph ology ▁▁ ▁This ▁par as ite ▁has ▁a ▁direct ▁lif ecycle ▁with ▁no ▁intermediate ▁hosts . ▁The ▁lif ecycle ▁takes ▁about ▁ 1 3 – 1 5 ▁days ▁to ▁complete . ▁In fect ed ▁m ice ▁pass ▁fa ec es ▁containing ▁eggs , ▁and ▁egg ▁sizes ▁vary ▁between ▁ 7 0 ▁and ▁ 8 4 ▁mic rom et res ▁( µ m ) ▁in ▁length ▁and ▁ 3 7 ▁and