Nutritional Programs for Lactating Sows
Dietary allowances for lactating sows | High intake needed
Modern sows can produce impressive quantities of milk, and that requires large amounts of energy, amino acids and other nutrients to support that milk production. It is, therefore, important that sows consume enough feed to supply those nutrients Inadequacy of nutrient intake can reduce milk production and/or cause mobilization of excessive amounts of maternal body tissue. It can also create metabolic/endocrine conditions that reduce the quality of the developing ovarian follicles that will produce the next litter of piglets.
Achievement of adequate feed intake by lactating sows is both very important and very difficult. However, feed intake can be encouraged by appropriate management. Heat stress should be minimized by appropriate environmental management steps, such as drip-cooling. The feeding process should be managed to encourage a high level of feed intake.
Fat | Supplementation of lactation diets with fat is unlikely to improve subsequent reproduction in most cases, but it almost always increases litter weaning weights and is recommended for that reason. This appears to be a specific physiological effect of dietary fat, not of energy density.
Amino acids | The amino acid requirements of lactating sows can be estimated by a factorial approach, as described above for finishing pigs. The factors to be considered are maintenance, requirements of the mammary gland for milk production, and the amino acids contributed by mobilization of maternal tissue. Again, the requirements for amino acids other than lysine are estimated using ratios.
The lysine requirement for maintenance is the same in relation to bodyweight as for finishing pigs. The requirement for the mammary gland is estimated to be 22 g apparent digestible lysine/kg litter growth.
Recent research from our laboratory indicates that the NRC (1998) estimate of the Valine:Lysine requirement ratio for milk production is too high. Correction of that ratio downward will allow use of more crystalline amino acids.
April 08 2008 10:28 am | Swine