Abstract
Preserved semen from breeding rams is essential for quick improvement of sheep production. This study was undertaken to observe the reproductive performances, semen quality, preservation of semen and it's fertility in indigenous ram. Concentrate supplementation (CS) @300 gm/ram/day along with traditional feeding improved body weight (24.1±2.2 vs. 20.8±2.3 kg), scrotal circumference (23.4±0.4 vs. 20.4±0.8 cm), growth rate (20.3±1.7 vs. 17.1±1.8g/day), semen volume (1.4+0.4 vs. 1.2±0.4 ml) and concentration (4.8±1.7± vs. 4.3±1.7 x 109/ml) of sperm (p<0.05). It improved motility (90.4±4.6, 81.9±4.6, 72.6±4.5 and 61.6±5.6 vs. 89.0±4.4, 80.2+4.1, 69.7+4.8, 58.7± 5.3 and 90.0±4.2%) and functional integrity (91.3±4.4, 80.6±4.4, 71.4±4.0, 59.6±4.9 vs. 90.0±4.2, 79.0±4.0, 69.3±4.0 and 58.1+4.1%) of spermatozoa after 0, 24, 36 and 48h of preservation, respectively. Pregnancy rates (PR) were higher after natural service (93%) than after transcervical artificial insemination TCAI (56%) (p<0.05). Chilled semen using TriladylR showed better motility (82.9±0.3, 75.5±0.3 vs. 80.4±0.3, 72.7±0.3%), viability (86.7±0.2, 78.7±0.2 vs. 84.8±0.2, 76.4±0.2%) and functional integrity (82.2±0.2, 74.4±0.2 vs. 79.8±0.3, 72.0±0.3%) of spermatozoa after 24 and 48h of preservation than locally manufactured extender (TFE), respectively. Among abnormal sperm, acrosome with Triladyl and tail with TFE were increased at 24 and 48h of preservation (p<0.001). Semen chilled and preserved with Triladyl or TFE for 24 and 48h were used for TCAI in natural and synchronized oestrrus ewes. Chilling TFE semen for 48h reduced PR compared with Tryladyl (5 vs. 32) (p<0.05). Ten percent EY was better with regard to motility and functional integrity of spermatozoa after 24 and 48h of preservation than others percentages. The motility of spermatozoa were positively correlated [r=0.467 (p<0.01)], [r=0.807 (p<0.01)] with viability and functional integrity of sperm, respectively. Functional integrity of sperm after chilling was positively correlated with normal morphology. Triladyl and TEF were used in three concentrations (200, 400, 600x106/ml) of spermatozoa. Three different concentrations (3, 5, 7%) of glycerol were used in frozen semen and TCAI was done for fertility evaluation. TFE reduced the sperm motility (44.5±0.6, 62.0±0.6, 41.9±0.6 vs. 36.6±0.6, 48.0±0.3, 35.0±0.6%), viability (46.6±0.6, 64.8v0.6, 46.6±0.6 vs. 38.1±0.6, 49.3±0.3, 38.1±0.6%), functional integrity (42.8±0.6, 50.2±0.5, 39.8±0.7 vs. 33.7±0.7, 36.2±0.2, 31.9±0.6%) and normal morphology (75.3±0.3, 77.0±0.4, 72.9±0.3 vs. 71.0±0.4, 74.6±0.6, 68.7±0.5%) compared with Triladyl(p<0.05). Concentration of spermatozoa significantly affected the frozen sperm quality within extender and between extenders (p<0.05). Sperm parameters increased at 400x106/ml compared with 200x106/ml or 600x106/ml (p<0.05). TCAI was done in natural and synchronized oestrus ewes using frozen semen with 400x106/ml sperm. Type of oestrus had no effect on PR. The quality of frozen semen was not different between 7 and 5% glycerol mixed extenders (p>0.05), Three percent glycerol decreased the semen quality (p<0.001). Laparoscopic artificial insemination (LAPAI) was followed by superior PR than TCAI (61.7 vs. 31.5%) (p<0.001). Fresh semen produced higher PR (75.7 and 57.1%) compared with chilled semen in both methods of AI. LAPAI at 20-24h of onset of oestrus was better than 12-16h (p<0.05). TCAI at 14-20h after onset of oestrus improved PR compared with 8-12h (p<0.05). Triladyl extended semen improved PR compared with TFE (p<0.05) in LAPAI and TCAI. Sperm concentration 400x106/ml produced better PR than 200 or 600x106/ml in both methods of AI. CS improved reproductive performances and semen quality. TFE could be used with sperm concentration of 400x106/ml for chilling or freezing of ram semen with similar fertility of Triladyl in TCAI. LAPAI was better to TCAI.