Sampling Boar Testes to Study Spermatogenesis Quantitatively and to Predict Sperm Production

Abstract
The volumetric proportions of eight testicular structures in boar testes were estimated histologically. Four predetermined areas were sampled to determine if each area were representative of the entire organ. Six 2-year-old boars (group 1) and nine 1-year-old boars (group II) were sampled. Boars in group I differed significantly with respect to spermatogonia, unclassified nuclei, total tubular cytoplasm, total tubule, intertubular tissue and artifacts. Similarly, the four locations sampled differed significantly with respect to lumen and total tubule. Boars in group II differed significantly with respect to primary spermatocytes, total tubule, non-tubular tissue and artifacts. Left and right testes did not differ in either group of boars, indicating that boar evaluation can be done by properly sampling one testis. A formula is proposed for converting the volumetric proportion of primary spermatocytes to predicted maximum daily sperm production (PMDSP). For group-I boars PMDSP was 31.3 × 109 and the corresponding value for group-II boars was 13.4 sx 109. The daily sperm output for group-I boars including estimated sperm losses in the collection procedure, was 19.7 × 109 sperm per day. The total sperm collected per day equalled 63.0% of the predicted values based on the histological data. The difference between these two values is considered to be primarily a function of in vivo sperm resorption, and losses in the urine. Copyright © 1964. American Society of Animal Science . Copyright 1964 by American Society of Animal Science