DefinePK

Abstract

Evaluation, dilution and preservation are the essential part of quality determination of native cock semen. Total of 21 semen samples were collected by abdominal massage from 7 native cocks at 3 days interval. Fresh semen was examined macroscopically for physical parameters. Most of the samples were found in yellowish white in color. The mean±SD volume, motility, concentration, dead and morphologically abnormal spermatozoa of semen samples varied from 0.3±0.01 to 0.5±0.03 ml, 58.3±2.9 to 71.7±3.5%, 3733±153 to 6067±130 x 106/ml, 22.3±4.51 to 33.7±1.53% and 18.3±7.8 to 30.7±1.5%, respectively. Cock # 1 showed the highest body weight (1.3 kg) and produced significantly (P<0.05) highest ejaculate volume and motility among the cocks. However, significantly (P<0.05) higher concentration of spermatozoa was observed in cock # 5 compared with others. The most frequent sperm abnormalities recorded in the mid-piece (8.5 to 13.0 %), followed by the head (3.5 to 6.0%) and tail (1.5 to 6.0%) of spermatozoa. After diluted in Lake A and Lake B (antibiotic added) diluents and preserved at 4ºC for two days, semen samples were examined on Day 0 (15 min chilled), Day 1 and Day 2, respectively. With the advancement of preservation, sperm motility, live spermatozoa and sperm morphology deteriorated progressively in both the diluents. However, significantly (P<0.05) higher percentage of motility was observed on Day 0 (60.6±2.4%) compared with Day 2 (39.2±2.0%) in Lake A diluent only. it was observed that Lake B diluent showed significantly (P<0.05) higher number of motile spermatozoa than Lake A on Day 1 and 2. Similar with the motility, significantly (P<0.05) higher proportion of live spermatozoa was present in Lake A on Day 0 compared with Day 2. However, proportion of live spermatozoa was significantly higher in Lake B than Lake A on Day2 only. Significantly higher (P<0.05) number of tail abnormality was present on Day 2 compared with Day 0 and 1 in both diluents. The overall abnormalities were found higher when diluted in Lake A than Lake B. The semen quality can be affected by the absence of antibiotic in the diluents and various preservation times.