ANS 3319C Reproductive Physiology and Endocrinology Lab Collection and Extension of Boar Semen Objectives 1) To introduce students to the collection of semen from the boar by the hand-glove technique. 2) To introduce students to the process of extending semen collected from a boar for use in on-farm artificial insemination. Semen Collection 1) Physical Examination a) HealthBoars must be disease free. Newly received boars are isolated for a minimum of 21 days before exposure to the breeding herd and tested for infectious diseases such as pseudorabies and brucellosis. They are also tested for prior exposure to parvovirus, leptospirosis, Haemophilus pleuropneumoniae, transmissable gastroenteritis, mycoplasma infections and eperythrozoonosis. The boar is evaluated for external and internal parasites and treated accordingly. All of these factors could affect herd reproductive performance. b) Body conditionBoars need to be in proper body condition (fat deposition) for their age and weight. Overly fat or thin boars can have a negative effect on reproduction. c) Conformation and body structureBoars need to have proper structure for locomotion primarily in the hind legs so that sexual performance is not affected (Figures 1a and 1b). Improper structure in the hind legs can severely limit the ability of the boar to mount and service the female or to mount the dummy during semen collection. . A B Figure 1a) Desirable conformation for the breeding boar. The top line and rump are level with a proper shoulder angle (A). The shoulder (B) and elbow (C) joints are pressure-absorbing joints. The pasterns (C) are sloping and long (60%) and also provide a cushioning effect. The rear legs and joints are properly angled to also provide a cushioning effect (E, F, G). The Boar in Figure 1b) is of undesirable conformation. The back is arched and the rump is steep. The front and hind limbs are straight resulting in no cushioning effect of the joints (B, C) while the hip, stifle and the hocks (E, F, G) are in a straight line.
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