Morfologia dos órgãos genitais masculinos e da cloaca da ema (Rhea americana americana)

Abstract

ABSTRACT.-Santos T.C., Sousa, J.A., Oliveira M.F., Santos J.M., Parizzi R. The rhea (Rhea americana americana) is a bird that belongs to the group of the Ratitas, order Rheiforme and family Rheidae. Macroscopic and microscopic morphology of the male genital organ (testes, epididymis, deferent ducts, and phallus) and the cloaca were analyzed in 23 emas, four chicken (2 weeks old), young (3 to 10 months old), and twelve adult ones (3 years old), from Cooperativa Emas do Brasil, RS and from CEMAS, Mossoró, RN. The testis of rhea had elongated shape and were located inside coelomatic cavity, in dorsal region of abdominal cavity, with medium length and width of 7.6±1.2cm and 2.6±0.7cm at adult animals; 4.5±1.5cm and 0.9±0.4cm at young animals; and 0.8±0.3cm, and 0.2±0.1cm at chicken. The testis were recovered by the tunica albuginea and its parenchyma had seminiferous tubules composed by spermatogenic epithelium and by sustentation cells, and also interstitial tissue, with interstitial endocrine cells, connective tissue and vessels. At the adult animals were observed all the cells from spermatogenic lineage, whilst at the youngs with 3 months the seminiferous tubules had a smale lumen with spermatogonia and undifferentiated sustentacular cells. The efferents ductus were composed by a cubic ciliated epithelium, while the epididimydis duct had a columnar epithelium. The epididymis was elongated and fusiform closely to medial testis board. The deferent duct had sinuous stretch at adult animals, rectilineae at young animal, convolute at its medium portion, decreasing its sigmoid shape at caudal portion, next to cloaca. The epithelium was pseudostratified ciliated, irregular lumen at adult animal, and circular at young animal, closely with urether. The cloaca was divided into three segments: coprodeum, urodeum and proctodeum. At urodeum the deferent ducts discharged into papillas at the ventral side wall, next to fibrous phallus's insertion. The phallus was a lymphatic fibrous organ, located at ventral wall, at the cloaca floor, and was composed by two portions: one rigid forked and twisted, and another simple spiraled and flexible, which normally was inverted. In forced exposition, the phallus had 14 cm in length. In a general way the Rhea genital organs shared the morphology from others birds, mainly those described to the ostrich.

Morphology of the copulatory organ in Ortalis canicollis (Aves: Cracidae) and early evolution of the phallus in birds

“…The blind tubular cavity has been described in this study as being the tubular portion of the phallus. In Ortalis canicollis , the blind tubular cavity is spiral‐shaped, similar to those described in Anseriformes (Guzsal, ; King, ), Tinamiformes (Oliveira & Mahecha, ) and Rheidae (Santos et al., ).…”

“…In Nothura maculosa (Oliveira & Mahecha, ), the fibrous body is present at the base and in the tubular portion of the phallus, and it serves as a support for these regions. Histologically, the fibrocartilaginous body of Cracidae is similar to those of Anatidae (Guzsal, ) and Rheidae (Müller 1836; Santos et al., ) because of the presence of chondrocyte. However, this pattern is different from those described in Tinamidae (Oliveira & Mahecha, ) and Struthionidae (Brennan & Prum, ), which do not possess cartilaginous tissue.…”

“…The phallus of birds shows polymorphism (Brennan et al, 2008;Herrera, Brennan, & Cohn, 2014;Oliveira, Silva, Santos, & Mahecha, 2004). Some species, as roosters and turkeys, possesses a small and non-intromittent phallic organ (King, 1981;Montgomerie & Briskie, 2007), while in other groups such as ratites (Brennan & Prum, 2011;Santos et al, 2011), many Tinamiformes (Oliveira & Mahecha, 2000;Oliveira et al, 2004), Anseriformes (Brennan et al, 2007;Coker, McKinney, Hays, Briggs, & Cheng, 2002) and cracids (Gadow & Selenka, 1891;Gerhardt, 1933), the copulatory organ is intromittent.…”

Morfologia e topografia do fígado e pâncreas de emas Rhea americana

“…Vários estudos vêm sendo realizados em emas, com o intuito de se conhecer a morfologia dessa ave, PARIZZI et al (2007;2008), a qual se apresenta com ovários e ovidutos, FORTES et al (2009), com sangue periférico, SANTOS et al (2011), com órgãos genitais, cloaca e língua, são alguns exemplos. AMBRÓSIO et al (2001) descrevem que as glândulas anexas do aparelho digestório das emas são o fígado e pâncreas.…”

Arterial vascularization of the cloacal bursa of the greater rhea (Rhea americana americana Linnaeus, 1758)

“…The literature provides few morphological studies with females (PARIZZI et al, 2007), cloaca of the males (SANTOS et al, 2011), digestory apparatus (RODRIGUES et al, 2012a;RODRIGUES et al, 2012b) and morphology of the blood cells (FORTES et al, 2009) in the rhea. There is no information on the morphology and vascularization of the cloacal bursa of the rhea.…”