Random regression models to estimate genetic parameters for weights in Murrah buffaloes

Area of Science:

• Animal Genetics
• Quantitative Genetics
• Livestock Breeding

Background:

• Understanding genetic factors influencing growth traits is crucial for livestock improvement.
• Murrah water buffaloes are an important dairy and draft animal, necessitating genetic studies for enhanced productivity.

Purpose of the Study:

• To analyze the genetic parameters of body weight at different ages in Murrah water buffaloes.
• To evaluate the potential for genetic selection for weight traits using random regression models.

Main Methods:

• Employed random regression models (RRM) with polynomial functions (3rd to 6th order) to estimate genetic parameters.
• Two models, M36 and M66, were utilized to describe direct genetic and permanent environmental effects.
• Heritability and genetic correlations were estimated across different ages.

Main Results:

• Heritability estimates for weight ranged from 0.16 to 0.42, varying by age and model used.
• Genetic correlations generally decreased as the time interval between measurements increased.
• Favorable genetic variability was identified, suggesting potential for selection.

Conclusions:

• Murrah water buffaloes possess significant genetic variation for weight traits, supporting selection programs.
• Genetic selection for improved weight is likely to be most effective when applied around 600 days of age.