Bovine Reproduction. Группа авторов

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Bovine Reproduction - Группа авторов


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      About the Companion Website

      The book is accompanied by a companion website at

      www.wiley.com/go/hopper/bovine Logo: Wiley

      The website includes:

       Figures in PPT

       Tables in PDF

Section I The Bull
Anatomy and Physiology

       Ben Nabors

       Department of Clinical Sciences, College of Veterinary Medicine, Mississippi State University, Starkville, MS, USA

Photo depicts components of spermatozoa.

Photo depicts histology of testicle. Photo depicts tissue layers of testicle.

      Testes

      The testes are housed in the scrotum. The scrotum is suspended between the thighs in the inguinal region. The scrotum consists of external and internal layers. The external layer is made up of the skin, tunica dartos, superficial perineal fascia, external spermatic fascia, cremasteric fascia, internal spermatic fascia, and parietal vaginal tunic. The skin of the scrotum and tunica dartos muscle are closely adhered whereas the fascial layers easily separate from the skin and the parietal vaginal tunic as in a closed castration technique. The coverings of the testicle itself consist of the visceral vaginal tunic and the tunica albuginea [2]. The visceral vaginal tunic is the innermost layer of the vaginal tunic, an outpouching of abdominal peritoneum that passes through the inguinal canal into the scrotal sac. The potential space between the parietal and visceral vaginal tunic is the vaginal cavity (Figure 1.3). The purpose of the vaginal cavity is for temperature regulation of the testicle by raising it closer to the body through contraction of the tunica dartos and cremaster muscles. The tunica albuginea is a thick fibrous capsule that covers the testicle and maintains the testicular contents under pressure [3]. Internally the tunica albuginea forms the axially positioned mediastinum testis from which connective tissue septa divide the testis into indistinct lobules. This connective tissue framework supports the vasculature, nerves, parenchyma, and tubular system of the testicle. The scrotum of the bull is pendulous due to the dorsoventral orientation of the testes contained within [1].

      Spermatic Cord

      The spermatic cord includes the ductus deferens, vasculature, lymphatic vessels, and nerves of the testicle and epididymis [4]. Essentially the spermatic cord consists of all the tissue within the vaginal tunic so it extends from the vaginal ring within the abdominal cavity to the testicle [5].

      Tubular Transport System

Photo depicts components of epididymis.
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