ifoam96.gif (1141 bytes)
Book of Abstracts
11th IFOAM
Scientific Conference
11-15 August 1996
Copenhagen, Denmark

Abstract front page
Subject index
Athor index

Symposia

Pigs on grassland supporting the crop production system S14

Andresen, Niels Kristian

Dep. of Anim. Nutrition and Management, Swed.Univ. of Agric. Sciences,Kungsängens Research Centre, S-753 23 Uppsala, Sweden

See also:
News from:
Organic.dk

Foraging pigs on grasslands can support the following crop and reduce inputs for soil tillage, manure application and weed control? An experimentwas carried out at Ekhaga Research Farm, Uppsala in 1995 (week 28 - 35).Forty slaughter pigs (LYH) with a weight around 40 kg were divided in 2x4 groups and introduced to two different types of grassland; a second years clover/grass ley and a more permanent pasture land.

The protein level in the supplementary feed and the stocking rate were varied. Every week the groups (five pigs) were moved to a new experimental plot with a size of 50 m2 or 100 m2.

All plots were grazed leaving no green matter. The grass intake contributed between 5% and 25% of the dry matter in the total feed ration. Behaviour observations on the clover grass ley showed that rooting increased from 10% of the observations on the low stocking rate to 17% on the bigger plots. Grazing behaviour was simultaneously lowered from 58% of the observations to 38%. The protein level in the supplementary feed was varied between 12,3% and 17,0%, but had minor influence on the foraging behaviour.

On the clover grass ley the 50 m2 plots were rooted to a depth of 4,5 cm, whereas the 100m2 plots were rooted to 3,1 cm. The corresponding effect on the pasture land was 3,5 cm on the small plots and 2,0 cm on the bigger plots. High clay content (54%) in the soil and low soil moisture had a negative impact on the effects.

The experience is that rooting as a »tillage tool« can be achieved with a high stocking rate and the efficiency will increase, if the soil moistureis high. Grazing will increase with a low stocking rate, when much grass of good quality is available.