Food fibers in gestating sows : effects on nutrition, behaviour, performances and waste in the environment

Abstract

Feeding gestating sows with high-fibre diets (HFD) has as a major interest to induce satiety without excessive energy intake. NDF (Neutral Detergent Fibre)) fibre content (15-20%) enables sows to adapt their feed intake to their needs. Therefore, ad libitum feeding becomes possible, reducing the cost of feeding equipment. Fibre effect on the feeling of satiety is due, among others, to the higher amounts of feed intake, the increase of eating time and the delay in gastric emptying. Sows welfare improvement due to the feeling of satiety has for consequence a reduction in the occurrence of stereotypes and aggressions. The disadvantage of HFD feeding is linked to a reduction, however limited, in the energy digestibility associated with an increase in the transit speed, a higher methane production and a reduction of cell component accessibility to digestive and microbial enzymes. However, energy efficiency of fibre degradation is better for sows than for growing pigs. If the amount of feed offered takes into account the reduction in energy digestibility, sow performance is not affected. Besides, the increased capacity of the digestive tract may result in an increased feed intake during early lactation, supporting higher milk production and limiting the body reserve mobilisation. On the environmental level, increasing fibre content reduces ammonia emissions but increases methane emissions.