Seminal, Biometric and Morphometric Profile of Nelore Bulls with Unspecific Orchitis

The biometric and seminal evaluation are broadly used in bulls selection, however, these methods are not effective to diagnose some reproductive diseases. The unspecific orchitis is characterized by discrete interstitial inflammatory infiltrate with lymphocytic predominance. In this context, in a study with 56 Nelore Bulls raised extensively in Mato Grosso do Sul state Brazil we selected ten animals diagnosed after histological analysis with unspecific orchitis (Orchitis Group = OG) and 12 with normal testis (Normal Group = NG). The animals were previously submitted to three seminal collect and measure of scrotal perimeter with 15 days interval. The sperm kinetics was subjectively evaluated by motility (%), vigor (1 - 5), and turbulence (1 - 4) and spermatic analysis was performed in semen sample stored in 10% formalin solution and was determined the percentage of the normal sperms and spermatic concentration. Representative fragments of testis were collected by orchiectomy and fixed in Bouin solution's by 24 hours. After fixation, the tissues were processed and stained with hematoxilin and eosin for histological and morphometric analysis. In morphometric analysis were measured: area of germinal epithelium (GE), area of tubular lumen (TL), area of Leydig cells (LC) and stromal area (SA). Statistical analysis was conducted by software BioEstat 5.3®. The non-parametric data was analyzed by Mann-Whitney test and parametric date by t test for independents samples. Data with variation coefficient more than 30% were subjected to angular (%) and logarithmic transformations. In animals of OG, histological analysis showed interstitial mononuclear infiltrate and low degree of degeneration of germinal epithelium. In measure of scrotal perimeter wasn't statistical differences (P >0.05) between NG and OG, 32.08 ± 0.90 and 31.80 ± 1.22 (mean ± sd) respectively. The motility of NG was 66.41 ± 10.25 and 44.00 ± 22.82 in OG, and these results was statistically different. Wherever, the results of vigor, NG = 4.00 ± 1.00 and OG = 2.50 ± 2.00, and turbulence, NG = 2.50 ± 1.00 and OG = 1.50 ± 1.00 (median ± interquartile range) is not significant (P = 0.09 and P = 0.07 respectively). Regarding the percentage of de normal sperm, wasn't statistical differences between periods in two groups, but when compared NG with OG the significance was observed only third collection (P < 0,01), being NG = 86.00 ± 4.81 and OG = 25.50 ± 23.82 (mean ± sd). The spermatic concentration, NG = 3.34 ± 1.56 and OG = 1.77 ± 1.49 (mean ± sd), was statistically significant (P < 0,05). The results of morphometric measures was: NG: GE= 53.17 ± 2.66%, TL= 23.17 ± 3.35%, LC= 3,75±1,36%, SA= 19.75 ± 4.18 and OG: GE = 49.70 ± 1.53%, TL= 24.90 ± 4.68%, LC= 4.60 ± 1.58, SA= 21.20 ± 5.53. In these measurements, there was statistical significance only in area of germinal epithelium (P < 0,05). The results of present study suggest that the unspecific orchitis affect significantly the fertility of bulls, probably due to chronic testicular degeneration associated with this process, leading to decrease in the germinal epithelium area. New investigation about etiology of unspecific orchitis should be carried, given that wasn't possible to identify the agent in this study.