Hvad sker der i fordøjelseskanalen med fiberrige fodermidler?

De senere års store interesse for anvendelse af grovfoder og fiberrige fodermidler til svin har sit afsæt i produktionsøkonomi, husdyrsundhed og velfærd samtg miljø. Dette har naturligt afstedkommet et ønske om mere viden og informtion om disse fodertypers næringsværdi og fysiologiske effekter i nutidens svineproduktion. Men hvad er grovfoder og fiberrige fodermidler? Hvad sker der med dem i svins fordøjelseskanal? Og hvilke positive og negative effekter kan det have på svinenes ernæringsstatus, sundhed og trivsel

Har grovfoder en ernæringsmæssig værdi for slagtesvin

I det økologiske husdyrhold skal dyrene have adgang til grovfoder. Grovfoderet skal ikke udgøre en bestemt andel af foderet, men være dagligt tilgængeligt for alle dyr. Grovfoderet tilfredsstiller dyrenes adfærdsmæssige behov mht. mæthed og rodeadfærd, og formodes at have en gavnlig virkning på deres sundhedstilstand. Ønsket om en øget økologisk svineproduktion påvirker økosystemets næringsstofbalance, hvorfor det er vigtigt at kende til svinenes bidrag hertil. Der er ikke særlig megen viden om, hvor godt svin udnytter grovfoder, fordi forskningen i mange år har været fokuseret på koncentrerede fodermidler, der giver maksimal foderudnyttelse og vækst. I projektet, som beskrives i det følgende, er der lavet nogle basale undersøgelser af, hvordan grovfoder nedbrydes i tarmkanalen, og hvor meget af energien og næringsstofferne i grovfoder der kan udnyttes af slagtesvin

Influence on the ileal and fecal digestibility of forages inclusion in the diet

The present investigation aimed to study the ileal and fecal digestibility of three forages (Clover grass, Clover grass silage and Pea-Barley silage) supplemented to a basal diet. A total of 24 pigs, adapted to eating forages by supplementing a basal feed with clover grass silage from weaning, were fitted with a T-cannula at the terminal ileum at approximate 30 kg LW. For each of the three types of forage, two balance trials with 4 weeks interval were carried out. Two pigs in each test were fed the basal diet while 6 others were fed the basal diet plus forage throughout the whole experiment. The intake of forages was relative low and quite variable and accounted on average for only 10-12 % of the daily dry matter intake. Ileal digestibility estimated by collection from the T-cannula was higher than the digestibility estimated by the slaughter technique indicating some separation of the digesta collected from the T-cannula. The forages had, as expected, a lower fecal DM and energy digestibility than the basal diet (P<0.05). The fresh clover grass had a higher energy digestibility than the two silages (60 vs 48 %, P<0.05). Inclusion of 10 % of gross energy in the diet from clover grass reduced the rations energy digestibility relatively by 2.2 %, while clover grass silage and the pea-barley silage to reductions of 3.4 and 5.0 % (P<0.05), respectively

Roughages for Growing Pigs, with Emphasis on Chemical composition, Ingestion and Faecal Digestibility

In 2 experiments, 10 gilts (30 kg initial liveweight) were given a basal diet with fresh or frozen/thawed clover-grass, clover-grass silage or whole-crop pea-barley silage. The faecal digestibility of gross energy (GE), DM, organic matter (OM), dietary fibre (DF) and CP were measured. The 3 roughages, leaves and stems of clover-grass and the basal diets were also tested for in vitro OM digestibility. Roughage intake was similar in both experiments and the average proportion of roughage ingested was 18-19% of DM. There were no differences between fresh and frozen/thawed clover-grass nutrient digestibility values. Glucose (cellulose) and xylose were the main constituents of the non-starch polysaccharides (NSP) in the roughages, with whole-crop pea-barley silage having the highest content. The faecal digestibility of NSP was significantly lower for diets based on whole-crop pea-barley silage than clover-grass silage. In both experiments, the GE, DM, OM and CP digestibility did not differ. Clover-grass leaves had higher in vitro OM digestibility than the stems

The ileal and total tract digestibility fibre and nutrients in pigs fed high-fibre cereal-based diets provided without and with a carbohydrase complex

The effect of carbohydrase can be variable according to the complexity of cereal grains and co-products. Studies on the effect of carbohydrase on cereal diets varying in complexity are scarce. This study was conducted to investigate the apparent ileal (AID) and total tract digestibility (ATTD) of energy, fibre and nutrients in pigs fed diets based on cereal grains and co-products without and with supplementation with a carbohydrase complex in the form of xylanase, arabinofuranosidase and β-glucanase. The experiment was carried out as an 8 × 4 Youden Square design (eight diets and four periods by two blocks) using 16 growing pigs (33.3 ± 0.8 kg) surgically fitted with a T-cannula in the terminal ileum. The pigs were fed eight experimental diets based on either – maize, wheat, rye, or a wheat and rye mix that were provided with or without enzyme supplementation. The AID and ATTD of DM, organic matter, energy, CP, fat, starch, and soluble and insoluble non-starch polysaccharides (NSPs) were studied using titanium dioxide as an indigestible marker. There was a cereal type effect (P  0.05). The ATTD of nutrients in the large intestine was mainly influenced by the fibre composition and was significantly lower (P  0.05). Collectively, the results indicate that the carbohydrase complex degrades AX in the stomach and small intestine, leading to a higher AID but with no influence on the ATTD of fibres, nutrients, and energy

Chemical composition and standardized ileal digestibility of protein and amino acids from blue mussel, starfish, and fish silage in pigs

Mussels cultured on lines for nine months and harvested in March were boiled to remove shells and processed into a dry meal or a silage acidified by formic acid. Starfish meal was prepared from starfish caught in May, and a starfish juice fraction was obtained by pressing fresh starfish. Commercial fish silage from farmed salmon was also included in the experiment. The standardized ileal digestibility (SID) of crude protein (CP) and amino acids (AA) was evaluated in a Latin square design with pigs (initial weight 39.3 kg) fitted with a simple T-cannula in the terminal ileum. Diets contained 131–162 g CP/kg and 5 g chromic oxide/kg. Endogenous losses of protein and AA were estimated by feeding an N-free diet. On a dry matter (DM) basis, mussel meal contained 605 g, mussel silage 575 g, starfish meal 700 g, starfish juice 393 g, and fish silage 776 g CP/kg. The ratio of AA to CP ranged from 0.83 to 0.87. The content of crude fat was high in the mussel products (157–161 g/kg DM), and the starfish meal and juice were high in ash (203 and 474 g/kg DM) with one-fourth being calcium. The AID of CP was 0.74, 0.81, 0.70, and 0.61 for mussel meal, mussel silage, starfish meal, and fish silage. The SID of CP was 0.83, 0.87, 0.80, and 0.68 for mussel meal, mussel silage, starfish meal, and fish silage. For both CP and AA digestibility, the lowest (P<0.05) was found in fish silage and the highest (P<0.05) in mussel silage. In conclusion, both mussel and starfish products showed chemical characteristics arguing for their use as feedstuffs in pig diets. Processing into silage rather than meal increased the SID of CP and AA, and both mussel products and starfish meal had greater SID compared to commercial fish silage