Fiber in Animal Nutrition

Fiber in Swine Nutrition 28 products (i.e. biscuits, whey etc.). Apart from the crude fiber content the structure of the feed is essential and should also be considered. Tail and ear biting the precursors of canni- balism have been a problem in swine rearing for decades. It is considered a multifactorial problem that has been brought under control in the past years via tail docking procedures. In many countries legislation is planning to ban this practice in the next years. The project “intact curly tail” under the guidance of Prof. Jaeger (2013) has combined infor- mation from literature studies, findings from organic farming (here pigs have intact tails) and current on farm trials to find the key factor responsible for the development of tail and ear biting. There is some evidence that necrosis is the cause and not the result of tail or ear biting. The exposure to endotoxins in early piglet rearing (i.e. produced by E. coli ) will cause damage to the blood vessel tissue in the peripheral regions of the body (tail, ears) resulting in inadequate circulation and death of these tissues. Due to the painful (tails retracted) and finally itchy necrosis pigs draw the attention of their pen mates and do not refuse chewing on necrotic areas with the results commonly observed (secondary infection, abscesses etc.) during tail biting. Stabilizing the GIT by providing flawless wa- ter and feeding diets with adequate structure and a higher crude fiber concentration can help prevent this disease process triggered by endotoxins. Stomach ulcers are also inf luenced by dietary fiber and feed structure. In order to improve digestibility feeds are milled and pelletized. In a review article Martens (2012) describes that current feed preparation along with strawless housing are the main factors resulting in stomach ulcers. Lacking feed structure impacts the layering in the stomach and a fast emptying rate is the consequence. The remaining feed content in the stomachhas a lowpHand gets in contact with unprotected regions of the stomach. Causing irritation and inf lammation resulting in stomach ulcers. In 2008 Große Liesner investigated the influence of feed structure and crude fiber content on the development of stomach ulcers in piglets. Here pelletizing feed and increasing the percentage of very fine particles (>0.4 mm) resulted in alterations of the mucosa and an increased number of lesions. Groups additionally fed with lignocellulose without adapting the feed structure tended to show gradually less damage of the mucosa. A higher stomach fill which is important for proper functioning was also observed in the lignocellulose groups. 2.5 Effect of fiber on swine performance 2.5.1 Sows Gestating sows are suited perfectly for fee- ding high fiber diets. They are fed restric- tively and although including f iber will reduce the energy content it will at the same time provide for larger feed volumes and prolonged feed intake time. Due to the fact that adolescent pigs utilize fiber sources well, sufficient energy is derived from fibrous feeds. Providing fibrous, high volume diets would satisfy the animals need to forage and would counteract the feelings of hunger. Hunger means stress. The connection between stress and infer- tility should not be underestimated. It is essential to reduce stress in early gestation. Physical and psychological stress reduces the concentration of the hormone progestero- ne. A low progesterone level results in early embryonic death and decreased litter size. © ERLING Verlag