Project manager: Magdalena Høøk-Presto
The aim of this thesis was to investigate the influence of dietary amino acid levels in a low-energy diet provided ad libitum on performance, carcass quality, behaviour and health of organic growing/finishing pigs in outdoor and indoor production systems. 192 piglets born outdoors were transferred to either a pen indoors (I) or a pasture outdoors (O). The pigs were allocated to six treatments (IR, IR-7, IR-14 and OR, OR-7, OR-14) with diets containing different amino acid levels. R was in accordance with the Swedish norm, R-7 and R-14 contained 7 and 14% lower levels than the norm.
The aim was also to determine whether additional roughage and access to outdoor areas affect activity behaviour and reduce aggression level among organic growing/finishing pigs. A total of 515 pigs in indoor housing systems with access to concrete outdoor runs were studied. The pigs were allocated to either a control treatment or one of three treatments with access to additional roughages in the outdoor run: hay, grass silage or whole crop barley silage.
Furthermore, the objective was to provide data on nutritional properties of some alternative organic protein feed resources. A 4-period changeover digestibility trial included pigs fitted with a post valve t-caecum cannula. The dietary treatments were faba bean and cake from hempseed, linseed and rapeseed.
The results showed that production system, rather than dietary amino acid level, affected pig performance and carcass quality and that pigs seem able to tolerate lower amino acid levels than the Swedish norm if fed ad libitum. The prevalence of erysipelas infections was higher in outdoor pigs and Ascaris suum infections were present in both production systems. Access to roughage and outdoor areas allowed pigs to express highly motivated natural behaviours, such as foraging, rooting and exploring, which generally resulted in a higher activity level. Roughage played an important role in occupying the pigs and reduced aggressions between the pigs. The alternative protein feed resources had satisfactory digestibility values and might have potential to be used to a greater extent in the formulation of organic pig diets.
Further reading: Doctoral Thesis (Full text)
For more information, please contact Magdalena Høøk-Presto
Organic Pig Meat Production - Nutrient Supply, Behaviour and Health
Doctoral Thesis
Swedish University of Agricultural Sciences, Uppsala 2008
Faculty of Veterinary Medicine and Animal Science/Department of Animal Nutrition and Management