Developmental comparisons of boars and barrows: II. Body composition and bone development

Area of Science:

• Animal Science
• Pork Production
• Comparative Anatomy

Background:

• Understanding carcass composition differences between male pigs (boars) and castrated males (barrows) is crucial for optimizing pork production.
• Previous research has indicated potential variations in muscle, fat, and bone deposition based on sex and weight.

Purpose of the Study:

• To compare the total carcass composition (bone, muscle, fat) and skeletal measurements (tibia, radius) between boars and barrows at various live weights.
• To determine the growth rates of different carcass components and bone dimensions in boars.

Main Methods:

• Carcass physical separation into skin, bone, and soft tissues for five replicates.
• Linear measurements of the tibia and radius for seven replicates.
• Comparative analysis of boars and barrows at 105 kg, and boars at 118, 132, and 145 kg live body weight.

Main Results:

• At 105 kg, boars exhibited significantly less fat (33.2%), more bone (11%), and more skin (14%) than barrows, with comparable fat-free muscle.
• Boar fat content at 145 kg was similar to barrow fat content at 105 kg.
• Linear growth rates for fat-free muscle, bone, and skin in boars from 105 to 145 kg were 0.41, 0.083, and 0.104 kg/kg, respectively.
• Bone weight-to-length ratio increased in boars with weight gain, indicating increased bone thickness.

Conclusions:

• Boars achieve comparable carcass fat levels to barrows at a significantly higher body weight.
• Boar carcasses are characterized by greater bone weight, attributed to increased bone thickness, compared to barrows.
• Skeletal and carcass components in boars exhibit predictable linear growth patterns within the studied weight range.