EFFECTS OF TRYPANOSOMA-CONGOLENSE INFECTI ON ON BAOULE BULL TESTIS - QUANTITATIVE HISTOLOGY AND MORPHOMETRY

The effect of Trypanosoma congolense on testis was studied in 53 trypa noresistant ''Baoule'' bulls by quantitative histology and morphometry . The daily spermatozoa production per testis of control groups (n = 4 5) was 382 +/- 334 x 10(6) (m +/- sd) and the epididymis contained 0.6 +/- 1 x 10(9) spermatozoa in the caput, 0.3 +/- 0.3 x 10(9) in the co rpus and 1.2 +/- 1.8 x 10(9) in the cauda. The infected bulls (n = 8) showed no significant difference (P > 0.05) when compared to the contr ol despite their average low value. The morphometric analysis during i nfection revealed a significant (P < 0.05) decrease (32%) of total Ley dig cell volume per testis, 4.4 +/- 0.9 cm(3) for the control (n = 5) and 3.0 +/- 0.8 cm(3) for infected bulls (n = 8). The number of round spermatids per Sertoli cell and the daily round spermatid production ( DRSP) per testis were also significantly reduced in infected bulls whe n compared to controls (P < 0.05), 5.2 +/- 0.7 and 2.8 +/- 2 for round spermatid per Sertoli cell and 6.1 +/- 20 and 3.1 +/- 1.9 x 10(8) for DRSP. These observations indicate that Trypanosoma congolense infecti on alters the interstitial tissue and meotic divisions of germinal cel ls leading to low daily round spermatid production per gram of testis in ''Baoule'' bulls.