Generation interval and Inbreeding in a population of Poll Dorset sheep

Mohsin Ayoub mir; Parvaiz Ahmed  Reshi; Abdul Qayoom Mir; Muzamil  Abdullah; zulfkarul Haq

Authors

Mohsin Ayoub mir National dairy research institute Author
Parvaiz Ahmed Reshi Author
Abdul Qayoom Mir Author
Muzamil Abdullah Author
zulfkarul Haq Author

Keywords:

Generation interval, Inbreeding, Poll Dorset Sheep.

Abstract

Pedigree records of 342 Poll Dorset sheep maintained at Mountain Research Centre for Sheep and Goat (MRSCG), Shuhama, during 1990 to 2024 were analysed for Generation interval and relatedness using ENDOG version 4.8 software package. Lambs born during 2016 and 2024 were considered as reference population. The mean generation interval for the reference population was 5.27 years, with longer Ram-Lamb interval than Ewe-Lamb pathway, indicating prolonged use of breeding rams and slower genetic gain. The average inbreeding coefficients for complete and reference populations were 5.65 and 15.47%, respectively, with average relatedness of 14.26 and 21.24%. The average numbers of maximum, complete and equivalent generation for the entire pedigree were 3.22, 1.92 and 2.45 respectively with corresponding inbreeding rate as 2.68%, 4.88% and 4.22% per generation, respectively. The Poll Dorset population exhibits critically high generation interval and inbreeding levels with a narrow genetic base where two ancestors contribute 50% of the gene pool. Immediate implementation of optimized rotational mating schemes, is recommended to restore genetic variability and ensure sustainable management of this unique genetic resource.

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References

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Generation interval and Inbreeding in a population of Poll Dorset sheep

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