Investigation of Body Development in Growing Holstein Heifers With Special Emphasis on Body Fat Development Using...

Area of Science:

• Animal Science
• Veterinary Medicine
• Biotechnology

Background:

• Growing heifers require precise monitoring of skeletal development and body condition for optimal health.
• Understanding the interplay between fat metabolism and skeletal growth is crucial for dairy cattle management.
• Existing methods for assessing body composition in heifers can be invasive or labor-intensive.

Purpose of the Study:

• To analyze skeletal development, body condition, and fat deposition in growing heifers.
• To evaluate the efficacy of bioelectrical impedance analysis (BIA) for assessing body fat in cattle.
• To investigate the relationship between fat metabolism, endocrine factors, and skeletal growth.

Main Methods:

• Studied 144 primiparous Holstein heifers aged 8-15 months from four dairy farms.
• Utilized body condition scoring, bioelectrical impedance analysis (BIA), back fat thickness, and body mass measurements.
• Analyzed pelvic measurements, sacrum height, serum metabolic/endocrine factors (leptin, IGF-1, E2), and feed composition.

Main Results:

• Bioelectrical impedance analysis (BIA) proved effective for evaluating fat tissue content in heifers.
• Observed a decrease in fat content concurrent with increased skeletal development from 8-15 months.
• Found correlations between high free fatty acid concentrations, skeletal growth, and endocrine markers.
• Noted a positive correlation between crude protein (CP) intake and body frame measurements.

Conclusions:

• Established a novel regression formula ('BIA-Heine') for BIA analysis in heifers to assess body composition.
• BIA offers an innovative, non-invasive technique for monitoring heifer development and supporting animal welfare.
• Demonstrated complex endocrine relationships influencing skeletal growth and fat metabolism in heifers.