Faculty of Veterinary Medicine University of Zagreb
Abstract
This study was carried out on 16 buffalo bulls (Bubalus bubalis) divided into four age groups, including three healthy (less than 5, 6 -10, and more than 11 year old animals), and one abnormal group (6 10 year old bulls having poor semen quality). The study was undertaken for a one year period divided into five seasons (dry summer, humid summer, autumn, winter and spring). Overall semen volume was 4.67±1.62 ml and showed a nonsignificant difference between age groups, although it was higher (P<0.05) in autumn. Overall semen pH was 6.55±0.50 and was lower (P<0.05) in the 6-10 than in the 11 year old bulls and the abnormal group. It was lower (P<0.05) in autumn while higher (P<0.05) in winter. Colour score was higher (P<0.05) in less than 5 year old bulls. However, it was lower (P<0.05) in the abnormal group than in healthy groups but was lower (P<0.05) in dry summer. Overall mass activity score was 2.65±1.03 and was lower (P<0.05) in more than 11 year old bulls. However, it was lower (P<0.05) in the abnormal than in healthy groups. Mass activity score was higher (P<0.05) in dry summer and spring. Overall sperm motility was 56.89±0.65% and showed no difference in healthy groups, but was lower (P<0.05) in the abnormal group. It was lower (P<0.05) in winter than humid summer and autumn. Overall sperm concentration was 1.00±0.50 millions/ml and was higher (P<0.05) in less than 5 year old bulls. However, it was lower (P<0.05) in the abnormal group. Sperm concentration was lower (P<0.05) in winter. The pH of semen showed negative (P<0.001) correlation with colour (r=-0.38), sperm concentration (r=-0.37), mass activity (r=-0.37) and motility (r=- 0.17). Sperm concentration correlated positively (P<0.001) with mass activity (r=0.86) and progressive motility (r=0.16).Istraživanje je izvedeno na 16 bivolskih bikova (Bubalus bubalis) podijeljenih u 4 dobne skupine, uključujući 3 skupine zdravih životinja u dobi do 5, između 6 i 10 i starijih od 11 godina, i od jedne skupine bikova starih između 6 i 10 godina s lošom kvalitetom sjemena. Istraživanje je trajalo jednu godinu tijekom 5 godišnjih doba: suho ljeto, vlažno ljeto, jesen, zima i proljeće. Prosječni volumen sjemena je bio 4,67±1,62 ml i nije pokazivao značajne razlike među dobnim skupinama, ali je bio veći (P<0,05) u jesen. Kiselost sjemena je bila pH 6,55±0,50 i bila je niža (P<0,05) u skupini 6 do 10-godišnjih nego u skupini bikova starijih od 11 godna i u bikova s ne kvalitetnim sjemenom. pH je bio niži (P<0,05) u jesen, a viši (P<0,05) zimi. Vrijednost boje bila je viša (P<0,05) u bikova do 5 godina starosti. Bila je, međutim, niža (P<0,05) u skupini bikova s lošom kvalitetom sjemena u odnosu na bikove s normalnom kvalitetom sjemena, te je bila niža tijekom suhog ljeta. Opća aktivnost sjemena bila je 2,65±1,03 i bila je niža (P<0,05) u bikova starijih od 11 godina. Bila je, međutim, niža (P<0,05) u skupini bikova s lošim sjemenom u odnosu na bikove s kvalitetnim sjemenom, te je bila viša (P<0,05) u suhom ljetu nego u proljeće. Ukupna pokretljivost spermija je bila 56,89±0,65% i nije pokazivala značajne razlike me|u bikovima s normalnim sjemenom, ali je bila niža (P<0,05) u skupine s nekvalitetnim sjemenom. Ukupna pokretljivost spermija bila je niža (P<0,05) zimi, nego u vlažnom ljetu i jeseni. Ukupna koncentracija spermija je bila 1,00±0,50 milijun/ml i bila je viša (P<0,05) u bikova do 5 godina starosti, dok je bila niža (P<0,05) u skupini bikova s nekvalitetnim sjemenom, kao što je bila niža (P<0,05) i zimi. Korelacija pH sjemena je bila negativna (P<0,001) s bojom (r=-0,38), s koncentracijom spermija (r=-0,37), s općom aktivinosti (r=-0,37) i progresivnom pokretljivošću (r=-0,17). Koncentracija spermija je bila u pozitivnoj korelaciji (P<0,001) sa masovnom aktivnosti (r=0,86) i progresivnom mobilnosti (r=0,16)
