Anatomical and Histological Organization of the Testes of the Inseminating CatfishTrachelyopterus striatulus(Steindachner, 1877) (Siluriformes: Auchenipteridae)

Abstract

The testicular morphology, spermatogenesis and occurrence of sperm in the ovarian lumen of Trachelyopterus striatulus were studied using anatomical, histological and biometric techniques. A total of 50 catfish (T. striatulus) were captured, measuring 14.9 ± 2.5 cm of standard length, body weight was 81.2 ± 34.5 g and their testes weighed 16.9 ± 6.1 g. The testes of T. striatulus are paired organs, showing two distinct regions: cranial, which shows a compact medial part and with fringes ventrally, and caudal region, which is formed of the seminal vesicle with fringes laterally and two saculiform expansions. The testes presented a length of 35.2 ± 6.9 mm, and the fringes showed a cranial length of 12.1 ± 3.8 mm and caudal length of 6.4 ± 2.6 mm. Histologically, the cranial fringes are spermatogenic and showed cells with significantly different nuclear diameters, ranging from 8.2 ± 1.5 μm (primary spermatogonia) to 1.88 ± 0.3 μm (spermatid). The seminal vesicles and saculiform expansions showed tubules with a simple prismatic secretory epithelium containing spermatozoa and secretion into the lumen. The caudal fringes are exclusively for secretory flow, consisting of tubules with a simple cuboidal epithelium. The common spermatic duct showed a simple cuboidal epithelium and contained spermatozoa with secretion into the lumen. The secretion of the caudal region is acidophilic, with neutral glycoproteins and sialomucin. T. striatulus ovaries showed free spermatozoa or were organized in spermatozeugmata into the ovarian lumen and between the ovuligers lamellae.

A case of intersex occurrence in Steindachneridion parahybae (Steindachner, 1877) (Siluriformes: Pimelodidae) under captivity condition: a cytogenetic and morphological study

“…These characteristic can be classified as "anastomosing tubular testes" (Grier, 1993;Parenti & Grier, 2004), and as spermatogonia were distributed along the entire extension of S. parahybae seminiferous tubules, it can also be classified as "spermatogonial unrestricted", according to Grier et al (1980). These features were similar to the pattern described for other Neotropical catfish species such as Conorhynchus conirostris (Lopes et al, 2004), Pseudoplatystoma fasciatum (Batlouni et al, 2006), Pimelodella vittata (Santos et al, 2010), Trachelyopterus striatulus (Santos et al, 2014), and others.…”

Gestao Do Turismo Em Unidades De Conservacao Estudo Sobre a Resex De Soure Marajo, Pará

“…O fato dos espermatozoides de A. ucayalensis apresentarem o núcleo alongado é mais uma evidência de que é inseminador. Alguns estudos têm demonstrado que núcleo alongando é uma das características necessárias para inseminação dentre as espécies de Auchenipteridae (MEISNER et al, 2000;PARREIRA et al, 2009;SANTOS et al, 2014). Tal característica facilitaria o deslocamento do espermatozoide no lúmen ovariano e entre as lamellas ovígeras (PARREIRA et al, 2009).…”

Morphometric and histological features of the testicles of cultured male broodstock African Catfish (Clarias gariepinus) at different ages

“…The histological features of the testicles of other breeds of catfish have been described (Santos, et al, 2014;Emam and Abughrien, 2014). Similarly, a few studies have reported on the morphological features of the testicles of C. gariepinus in Nigeria (Ikpegbu et al, 2012;Eyo et al, 2012, Ajala et al, 2015.…”