A bipartição escrotal e sua influência nos parâmetros reprodutivos de ovinos criados no Sertão Paraibano.

Abstract

A field and slaughter survey was conducted in order to quantify the presence of scrotal bipartition in sheep raised in the Sertão Paraibano and, in a second study, the influence of scrotal morphology on thermoregulation and semen quality was evaluated. The scrotum of 331 sheep, from rural properties in the Patos-PB micro-region, and 456 sheep slaughtered at the Patos-PB Municipal Slaughterhouse were examined. It was observed that 66.67% of the visited properties presented animals with the characteristic, with a prevalence of 11.48% in the properties and 14.47% in the slaughterhouse. The degree of bipartition was 9.59 ± 1.035% of the total length of the scrotum for the animals in the field and 12.89 ± 0.749% for those of the slaughterhouse, characterizing bipartition less than 50% of the scrotal length. The intensive breeding variables (OR = 16.6) and Dorper breed (OR = 6.91) were identified as risk factors associated with the presence of scrotal bipartition. In the second experiment, 14 undefined sheep were used, divided into two groups, GI composed of 7 animals with bipartition and GII of 7 animals without scrotal bipartition. Capturing images of the animal's body and the caudal face of the scrotum were performed using the Fluke thermographic camera (Ti25®). The images were analyzed by computer software (SmartView ™ software), tracing lines in the proximal, middle and distal thirds of the testis and tail of the epididymis, showing the maximum, average and minimum temperature of each delimited area. For semen analysis, two harvests were performed by means of electroejaculation, with automatic device (Boijektor-2001). Macroscopic (volume) and microscopic parameters (turbulence, progressive motility and vigor) were analyzed. The superficial temperatures of the proximal, middle and distal regions of the testis and tail of the epididymis showed no significant statistical difference (p> 0.05) between the groups. The studied seminal parameters, in both groups, were within the desirable values for the species, indicating no significant difference (p> 0.05) between the groups. It was observed higher scroto-testicular biometric values and body weight in sheep with scrotal bipartition (p <0.05). It is concluded that scrotal bipartition is a characteristic present in sheep raised in the municipality of Patos in the semi-arid region of Paraiba, observing a high prevalence of properties with bipartite sheep, but a small number of animals with scrotal bipartition was identified and there was no influence of bipartition Scrotal surface temperature and seminal quality of sheep, but other research should be carried out to better evaluate the influence of this trait on the reproductive parameters of these animals.