A degree of reluctance seems to persist towards a high rye ratio in the diet. Older observations report that higher proportions of rye in the feed ration leads to a decrease in feed intake, joint ill and a change in faeces consistency. Today, numerous trial results have shown that this reluctance is unreasonable because, among other things, breeding has achieved that bitterness plays a minor role in today‘s varieties.
However, two limiting factors in rye cannot be denied. One is the high proportion of non-starch polysaccharides (NSP) which are difficult to digest and the other is the susceptibility to infection with the ergot fungus Claviceps purpurea. Thresholds for ergot and mycotoxins are considered in regard to using rye in human as well as in animal nutrition in order to control toxicity risks. It is prohibited to exceed the statutory maximum level of 1 g per kg of cereal grain. Compared to wheat and barley rye has significantly lower levels of the Fusarium toxins deoxynivalenol and zearalenone. Having taken these limiting factors into account the DLG (German Agriculture Society) issued recommendations on the use of rye in the year 2006 (see tables).
|up to ... % rye within feeding ration|
|Fattening pigs 1|
|28 - 40 kg LW (pre-grower)||30|
|40 - 60 kg LW (grower)||40|
|60 - 90 kg LW (pre-finisher)||50|
|> 90 kg LW (finisher)||50|
|up to 15 kg LW||10|
|from 15 kg LW||20|