Hosts: Sheep, Rocky Mountain bighorn sheep, moufflon, roe deer.
Location: Uncertain, presumably abomasum and small intestine.
Geographic Distribution: Worldwide.
Prevalence: This species is fairly common. Christensen (1938a) found it in 14% of 100 sheep from Maryland, New York and Wyoming. Jacob (1943) found it in 13% of 100 sheep in Germany. Balozet (1932) found it in 3% of 63 sheep in Tunisia. Svanbaev (1957) found it in 4% of 302 sheep in Kazakhstan.
Morphology: This species has been described by Spiegl (1925), Balozet (1932) and Christensen (1938a). The oocysts are ellipsoidal, 39 to 54 by 27 to 36 u with a mean of 47.0 by 32.0 u (Christensen) or 45.6 by 33.0 u (Spiegl). Their length-width ratio is 1.3 to 1.8 with a mean of 1.47. The oocyst wall, as described by Henry (1932), is composed of 3 layers; the outer layer is a transparent, colorless membrane which is very difficult to see; the middle layer is thick, rough, brown, transversely striated, 2.0 to 2.5 u thick, and somewhat thinner at the micropylar end; the inner layer is colorless, 0.8 to 1.0 u thick. The micropyle is prominent, 6 to 10 u in diameter; it does not extend to the inner layer. The micropylar cap is prominent, transparent, colorless to yellowish-green, crescent-shaped, detachable, and 6 to 11 u wide and 1 to 3 u high with a mean of 9 by 2 u. An oocyst polar granule and residuum are absent. The sporocysts are elongate ovoid, 17 to 18 by 9 to 13 u, with a small Stieda body and a sporocyst residuum. The sporozoites are wedge-shaped, with several refractile globules. The sporulation time is 3 to 5 days.
Life Cycle: The life cycle of E. intricata has not been worked out. As mentioned above, Reichenow (1940) and Becker (1956) considered that the giant schizonts described from sheep under the name E. gilruthi are those of E. intricata. According to Kotlan, Pellerdy and Versenyi (1951), the merozoites of E. intricata are about 16 u long and bent like a hoe at one end.
Pathogenesis: Unknown. These oocysts are rarely found in large numbers.
Epidemiology: Honess (1952) found this species in the Rocky Mountain bighorn sheep, and Wetzel and Enigk (1936) reported it from the roe deer in Germany.