The morphological characters of the male external genitalia of the European hedgehog (Erinaceus Europaeus)

Abstract

This study was conducted to depict anatomical characteristics of the penis of he-dgehog. Seven sexually mature male European hedgehogs were used. Following anaesthesia, the animals were scarified with chloroform inhalation. Gross penile characteristics such as length and diameter were thoroughly explored and measu-red using digital callipers. Tissue samples stained with haematoxylin and eosin and Masson's trichrome for microscopic analysis. The penis of the European hedgehog was composed of a pair of corpus cavernosum penis and the glans penis without corpus spongiosum penis. The urethra at the end of penis, protruded as urethral process, on both sides of which two black nail-like structures, could be observed. The lower part was rounded forming a blind sac (sacculus urethralis) with a me-dian split below the urethra. Microscopically, the penile bulb lacked the corpus spongiosum penis, but, corpus spongiosum glans was seen at the beginning of the free part. In the European hedgehog, entirely stratified squamous epithelium of penile urethra, absence of corpus spongiosum penis around the urethra and bilateral urethral glands are basically different compared with other mammals. This information is expected to contribute to comparative penile morphology as well as for testing phylogenic hypotheses and expanding knowledge about reproductive biology in this animal. (Folia Morphol 2018; 77, 2: 293-300).

Morphogenesis of penis and spongy urethraduring human gestation

“…Simultaneously, the urogenital sinus originates from urogenital folds that form scrotal bags ( 15), (27). Two weeks later, the testicles differentiate and secrete testosterone, which acts over the genital tubercle and the urogenital folds, inducing masculinization of the external genitalia (6). For the development of the folds, the genital tubercle grows to form the penis, whereas the urogenital fold enlarges and closes, forming the spongy portion of the masculine urethra on the medium raphe, which starts in the eighth week of intrauterine life following a fusion that starts from the base to the tip of the phallus (28).…”

“…Even though the male external genital differentiation is a very detailed process, there are still migration and cellular differentiation processes that need to be studied further, since in many cases, most of the information has been obtained from studies in mice models (4)(5)(6). Despite the fact that, by studying murines, relevant information has been found and access to experimental manipulation has been given, it is important to note that they have some anatomical and morphological differences when compared to humans, which presents a difficulty when trying to use direct analogies (7) (8).…”

Kızıl tilkilerde (Vulpes vulpes) testis, penis ve prostat’ın arteriyel vaskülarizasyonu, makroanatomik ve histolojik yapısı

“…The mean penis length was 96.56 ± 7.00 mm in red foxes, 170 mm in Iraq dogs (Alaa 2016), 179 mm in all other dogs (Miller 1964), 50 mm in hedgehogs (Atalar and Ceribaşı 2004), 7.17 mm in the Western European hedgehog (Akbari et al 2018), 54.6 mm in rodents (Adebayo et al 2011), and 50-80 mm in the cat (König and Liebich 2015). The penis length in the red fox is between the minimum and maximum values of that in other animals within the same family.…”

Postnatal growth of the lumbosacral spinal segments in cat: Their lengths and positions in relation to vertebrae

“…The level of ascension is a characteristic for a particular species and probably depends on its adaptation to environmental factors rather than on their phylogenetic position. For example, the spinal cord ending in midthoracic vertebral region in echidna (Ashwell & Zhang, 1997), tree pangolin (Imam et al, 2017), and hedgehog (Malinska et al, 1972) enables them to take the defensive positions (Ashwell, 2013), and the hindlimb loss of cetaceans (Ridgway, 2012; Seki, 1958; Sobolevskiĭ, 1978), the aquatic limb specialization in pinnipeds (Machado et al, 2003; Sobolevskiĭ, 1978) and a poor development of hindlimbs in bats (Kapoun et al, 1973; Neuweiler, 2000) also lead to the development of a short spinal cord. The long prehensile tail in monkeys leads to the development of a relatively long spinal cord (Chang & Ruch, 1947; de Souza Terra et al, 2018).…”