Composition of sow milk during lactation

Area of Science:

• Animal Science
• Dairy Science
• Veterinary Medicine

Background:

• Sow colostrum composition is critical for neonatal piglet immunity and nutrition.
• Understanding the dynamic changes in milk composition throughout lactation is essential for optimizing piglet growth and health.

Purpose of the Study:

• To quantitatively analyze the changes in sow colostrum and milk composition during lactation.
• To identify the key components and their alterations from colostrum to mature milk.

Main Methods:

• Quantification of total solids, protein, fat, and lactose in sow milk.
• Analysis of milk samples from 25 German Landrace sows at 14 time points.
• Immunoglobulin (Ig) profiling, including IgG and IgA, throughout lactation.

Main Results:

• Colostrum (first 6 hours) exhibited higher total solids and protein, with lower fat and lactose compared to mature milk.
• A significant decrease in total protein and whey protein, alongside increased fat and lactose, marked the transition to mature milk.
• Immunoglobulin G (IgG) dominated colostrum protein, while Immunoglobulin A (IgA) increased to 40% of whey protein by lactation end.
• Lactation number and litter size did not significantly influence milk composition.

Conclusions:

• Sow milk undergoes a distinct compositional shift from colostrum to mature milk, primarily driven by changes in immunoglobulin and nutrient profiles.
• The transition is characterized by a decrease in protein and an increase in fat and lactose.
• Immunoglobulins play a crucial role in early lactation, with IgA becoming prominent later in lactation.