Fertility of oestrus synchronised crossbred Malabari does inseminated with boer buck semen

Abstract

With the objective of studying the fertility of frozen Boer buck semen, six Boer bucks maintained at Goat Breeding Station, Dhoni farm, Kerala Livestock Development Board and 150 Malabari crossbred does maintained at Sheep and Goat farm, Mannuthy were selected. Semen collection was carried out at weekly intervals from the bucks and preserved under freezing. Average volume of buck semen was 1.27 ± 0.06 rnl. Colour of the semen was creamy, density DDDD and mass activity + + + +. Average sperm concentration of the semen samples was 2956.67 ± 81.74 millions per ml and mean live sperm percentage was 88.16 ± 0.50. Average semen pH was 6.98 ± 0.03. No significant difference was found in these semen characters between bucks (P>0.05). Average percentage of abnormal spermatozoa in the fresh semen was 3.20 ± 0.27. Mean percentage of sperms with abnormal acrosome was 1.00 ± 0.13. The does selected were administered 0.147 mg Tiaprost Trometamol, a prostaglandin analogue (0.75 ml Iliren) intramuscularly at 11 days interval for oestrus synchronisation. The does were divided into two groups, Group I with 100 does and Group II with 50 does. Ninety six does in Group I and 47 does in group 11 responded to the treatment. Incidence of oestr~s in the does was 95.33 per cent. Average time taken for the does to come to oestrus was 51.02 ± 0.99 hours. Mean duration of oestrus in the does was 35.81 ± 0.86 hours. Average oestrus intensity score in the does was 5.97 ± 0.41. Wagging of tail (65.33 per cent), frequent bleating (56.67 per cent), vulal oedema (43.33 per cent) and standing to be mounted (34 per cent) were the prominent signs of oestrus exhibited by the does. Six semen samples from each buck were frozen in Tris and Biociphos extenders separately. Progressive motility of semen samples after washing twice in Tris buffer and after thawing was 67.00 ± 1.47 and 43.91 ± 1.86 per cent. Average

percentage of live sperms in the fresh semen and after thawing was 87.83 ± 0.75 and 52.61 ± 1.56. Mean percentage of sperm motility after initial dilution and freezing and thawing in Biociphos extender was 80.56 ± 1.11 and 40.19 ± 1.87. Percentage of live spermatozoa in fresh semen and thawed semen was 87.64 ± 0.76 and 43.64 ± 1.49. Though no significant difference was noticed in post thaw motility of spermatozoa, highly significant variation was observed in the percentage of live spermatozoa between the semen frozen in Tris and Biociphos extenders (P>0.05). Artificial insemination was carried out in all the oestrus does by speculum method. Group I does were inseminated with semen extended in Tris and Group JJ does with semen extended in Biociphos. Pregnancy diagnosis was done at three months of gestation by abdominal palpation and the accuracy of the method was found to be 93.55 per cent. Conception percentage in Group I and Group n was 22.92 and 19.15. There was no significant difference in the conception rate between the two groups. Mean gestation length was 147.23 ± 0.76 days. Number of kids per kidding averaged 1.77. Percentage of male and female kids was 50.91 and 49.09. Average birth weight of kids was 2.38 ± 0.08 kg.