Grade. 

 Date.. 



EXERCISE 20 

 THE REPRODUCTIVE SYSTEM OF THE HEN 



Object. — To dissect and study in detail the reproductive system of the 

 hen and to become familiar with the process of egg formation. 



Equipment. — A nimiber of hens (1) one or more in laying condition, (2) 

 one immature pullet, and (3) one old hen, very fat. 



Procedure. — Study these three different types of specimens -as follows: 



Step 1. — Open the birds for post-mortem inspection as directed in Ex- 

 ercise 19. Remove organs of digestion and circulation carefully, exposing 

 the reproductive system. 



Step 2. — Study in detail the location, size and appearance of the ova- 

 ries and oviduct in each specimen. Take complete notes regarding them. 

 Where possible a number of birds should be studied in respect to ovarian 

 development. 



Ovaries and Ovules 



Condition of Ovary Number of Large Ovules* Number of Small Ovules 



Totals 



Average 



* A large ovule should be at least one-quarter of an inch in diameter. 



Step 3. — Carefully dissect the ovary and count the number of o\'ules (a 

 hand lens will be a help in counting the small ones) . Note the variation in 

 size and color. 



Step 4, — Carefully dissect the o^'iduct and remove to the dissecting 

 tray. Note external appearance of the different sections. 

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