Sigvard Thomke

Influence of increasing levels of β-glucanase on the productive value of barley diets for broiler chickens

The influence on the productive value of diets for broiler chickens based on barley harvested at two stages of ripeness, when including β-glucanase in increasing amounts, was evaluated in a production experiment over three weeks. Feed consumption and live weight increased (P < 0.001) and feed conversion was improved (P < 0.001) by including β-glucanase in the diets. Dry matter content of excreta increased significantly as a result of β-glucanase inclusion. Broiler chickens receiving diets based on barley harvested at combine ripeness were slightly heavier (P < 0.05) at three weeks than those fed on barley harvested at early yellow ripeness.

The effects of feeding system, lysine level and gilt contact on performance, skatole levels and economy of entire male pigs

Abstract The study embracing 1528 crossbred entire male (EM), female (F) and castrated (C) pigs (26–105 kg live weight, LW) was aimed at studying the effects of different environmental factors such as feeding system, diet composition, raising in single-sex and mixed groups, and feeding and grouping routines prior to slaughter on performance and backfat skatole levels. Furthermore, the profitability of the different sexes was calculated. The pigs were fed restrictedly a dry or a wet (whey or water) diet containing either 0.85, 0.95 or 1.05% lysine. The evening before slaughter the pigs were either fed or not. During transport and lairage before slaughter, one half of the pigs were mixed with unfamiliar pigs of all sexes, while the other half were handled pen-wise. In comparison with C, EM pigs had superior daily weight gain (DWG, + 23 g/d) and feed efficiency (−0.15 kg feed/kg weight gain). In the LW range from 60 kg to slaugther EM raised in groups together with F had a tendency to exhibit a lower DWG, compared with raising in single-sex groups. Carcass lean meat percentage in EM exceeded that of C by 4.1 units when estimated by partial dissection. In the LW range from start to 60 kg, pigs fed the highest lysine level (1.05%) had a higher DWG than pigs fed lower lysine levels (0.85 and 0.95%). Lysine level had no effect on carcass lean meat percentage. Wet feeding with whey, but not with water, reduced backfat skatole levels, in comparison with dry feeding. Pigs fed the higher vis-a-vis the lower lysine level had higher skatole levels in trial 1, whereas in trial 2 there was no effect. Contact with F pigs in the pen tended to reduce fat skatole level in EM. Neither feeding routines nor mixing with unfamiliar pigs prior to slaughter affected skatole level in backfat, except for a reduction in nonfed pigs, mixed with unfamiliar pigs prior to slaughter. Gross margin per pig place and year did not distinguish EM from C when graded commercially, but was significantly superior for EM when payment was based on dissected carcass lean meat percentage.

Nutrient digestibility and protein quality of oats differing in chemical composition evaluated in rats and by an in vitro technique

The relationship between a number of chemical components and the nutritive value of 15 oat samples was studied in vivo with rats and in vitro with an enzymatic method. Also the effects of varying crude protein (CP) content of oat samples on amino acid (AA) pattern and protein quality were studied. The content of total fibre was calculated as the residual fraction after substraction of the analysed content of sugars, starch, CP, crude fat and ash from the dry matter content. There were significant negative correlations (r = −0.52 to −0.74) between total fibre and in vivo true N digestibility (TND), digestibility of energy (DE)(P < 0.01), biological value (BV) and net protein utilisation (NPU) (P < 0.05). Positive correlations (r = +0.61 to +0.65) were also found between starch content and BV (P < 0.05) and NPU (P < 0.01). The in vitro total tract DM digestibility and in vitro ileal DM digestibility were negatively correlated to total fibre (P < 0.01) and positively correlated to starch content and DE (P < 0.01), respectively. The in vitro total tract and ileal CP digestibility correlated positively to levels of CP (P < 0.05 and P < 0.001, respectively) and soluble β-glucans (P < 0.001 and P < 0.01, respectively). There were significant relationships between CP of oats and the content in CP of cysteine, methionine + cysteine, histidine (P < 0.001), serine, glycine (P < 0.01), aspartic acid and tyrosine (P < 0.05). However, with the exception of phenylalanine (P < 0.05), the variation in AA composition did not affect BV.

Nutritive value of oats of different composition evaluated by intact and fistulated pigs

Heal and total tract digestibilities of dietary components and energy in eight oat diets varying in chemical composition were studied with growing pigs in two 4×4 Latin square experiments. The diet with partially dehulled oats had the significantly (P < 0.05) highest ileal and total tract digestibility of organic matter, crude protein, total fibre and energy. The metabolizable energy value of the oat batches tested varied between 15.4 and 10.9 MJ kg‐1 dry matter. Significant correlations (P < 0.05) were found between both total tract and ileal digestibilities of organic matter and energy, respectively, and the content of fibre components, starch, crude fat and nitrogen‐free extractives. Differences in the correlations as predictors between the content of crude fibre, total fibre, neutral detergent fibre or acid detergent fibre and the ileal and total tract digestibility of organic matter and energy, respectively, were limited.

Dietary Energy and Protein for Growing Pigs: 1. Performance and Carcass Composition

Abstract In a joint Nordic project, four experiments with a total of 880 growing pigs following the same outline were conducted in Denmark, Norway, Finland and Sweden. In three of these experiments the animals were fed individually. Five dietary treatments were investigated with respect to effects on performance, carcass composition and leg condition by entire or partial dissection. The treatments were: (1) restricted standard feeding as a reference in all experiments; (2) ad libitum feeding with protein (amino acid) concentrations according to recommended allowances (RA); (3) as in (2) but RA increased by 10% (RA + 10%); (4) as in (2) but RA lowered by 10% (RA - 10%), or (5) the most common restricted feeding scale recommended in the individual countries, thus being different from experiment to experiment. Compared with the restricted standard feeding, for which daily feed intake and daily weight gain in the weight range 23–100 kg averaged 2.07 kg and 750 g, respectively (rel. value 100), the correspondi...

The Nutritive Value of Lucerne Leaf Meal for Pigs Based on Digestibility and Nitrogen Utilization

Abstract Digestibility, energy metabolism and nitrogen utilization of a barley-based diet with increasing inclusion of lucerne leaf meal (LLM; 0, 5, 10 and 20%) were studied in a change-over experiment with growing pigs. In addition, digestibility and nitrogen utilization of the diets were evaluated with rats. The apparent digestibility of fibre increased with LLM inclusion, whereas the digestibility of organic matter, crude protein, fat and energy all decreased significantly. There was a significant reduction in the dietary content of digestible and metabolizable energy with increasing inclusion of LLM in the diet. Nitrogen retention and utilization were significantly increased with an increasing inclusion of LLM.

Performance, behaviour and immune capacity of domestic pigs reared for slaughter as siblings or transported and reared in mixed groups

The possible relationship between performance, behaviour and immune capacity was studied in pigs reared for slaughter as siblings or in mixed groups in 2 x 5 pens of 9–10 pigs in each, i.e. 48 and 49 individuals, respectively. Kilogram feed per kg weight gain was lower (4%) and daily weight gain was higher (3%) for the siblings, which also showed the lowest level of agonistic interactions, as compared with the mixed groups. No direct relationships between agonistic interactions, plasma cortisol and measures of “immune capacity”; (total and differential leukocyte counts, mitogen‐induced proliferation and interleukin‐2 production in vitro) were found. The order of voluntarily leaving a pen and entering a scale were correlated to individual intra‐pen weight ranking class; this ranking could be predicted by an x‐matrix of the blood variables when subjected to partial least square analysis. Thus, a linkage between weight ranking class and physiological variables could be observed.

Dietary Energy and Protein for Growing Pigs: 2. Protein and Fat Accretion and Organ Weights of Animals Slaughtered at 20, 50, 80 and 110 kg Live Weight

Abstract This investigation was performed to study the effects of restricted versus ad libitum feeding on carcass composition, on protein and fat accretion and on body development and organ weights. The carcass composition was evaluated on 168 pigs by serial slaughter at 20, 50, 80 and 110 kg LW. The chemical composition was examined in only 62 of these animals. The carcasses were partitioned into four cuts and dissected into lean meat, fatty tissue, rind and bones. Ad libitum feeding resulted in daily weight gain exceeding restricted feeding in the three weight ranges by 42%, 17% and 7% and feed conversion ratios by 3%, 15% and 9%, respectively. Castrated males exceeded daily weight gains of females by 6%. At 20 kg the carcass moisture content was 65% for both sexes, which on average over feed regimens at 110 kg decreased to 56% and 52% for females and castrated males, respectively. Correspondingly, the carcass crude fat (CF) content increased from 13% to 24% and 30%, respectively. At 110 kg LW on restri...

Protein quality studies on rats fed on cassava-root meal enriched with Cephalosporium eichhorniae 152 or with conventional plant-protein supplements

Abstract Using rats, the protein content and quality of an enriched cassava-root meal (CRM) biomass, produced by growing Cephalosporium eichhorniae 152 on a CRM medium in a submerged fermentation, was compared with that of soya-bean meal (SBM) and cotton-seed cake (CSC) in rats. The contents of crude protein of these feeds were 38.8, 52.0 and 42.3% on DM basis, respectively, and there were differences in their amino acid composition. The nitrogen digestibility of the enriched CRM-biomass and of CSC was lower than that of SBM. The biological value of the enriched CRM-biomass was equal to that of CSC, but lower than that of SBM. Net protein-utilization estimates for the enriched CRM-biomass and for CSC were similar, whereas that for SEM was greater. Enriching CRM by C. eichhorniae 152 seems to be a way of increasing protein supply for livestock production.