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The objective of this trial was to investigate the influences of conjugated linoleic acid ( CLA) and vitamin E (Vit. E) and their interactions on fatty acid composition and vitamins in milk (α-tocopherol, retinol and β-carotene) as well as on α-tocopherol in blood of pluriparous cows from week 6 ante partum until week 10 post-partum (p.p.). We assigned 59 pluriparous German Holstein cows to four treatment groups with the treatment factors CLA and Vit. E at two levels in a 2 × 2 factorial design. Milk fatty acid composition and milk vitamins were analysed on lactation days 7 and 28. α-tocopherol in blood serum was analysed on days −42, −7, 1, 7, 14, 28 and 70 relative to parturition. Milk concentration of α-tocopherol was influenced by Vit. E ( p < .001) and CLA ( p = .034). Percentage of cis-9, trans-11 CLA in total milk fat was influenced by treatment with CLA ( p < .001), while for percentage of trans-10, cis-12 CLA an interaction between treatment and day ( p = .019), driven by an increase in both CLA groups from day 7 to day 28, was found. Serum ratios of α-tocopherol to cholesterol were influenced by Vit. E ( p < .001). Results suggest that treatment with CLA during late pregnancy and early lactation is suitable to enhance the proportion of trans-10, cis-12 CLA in milk and thereby influencing nutritional properties. As treatment with Vit. E did not have an impact on milk fatty acid composition, it might be possible to increase the antioxidative capacity of the dairy cow without affecting milk properties. Consequently, combined treatment with CLA and Vit. E might elicit synergistic effects on the cow and milk quality by increasing the proportion of CLA in milk fat as well as the excretion of Vit. E and the Vit. E levels in serum. [ABSTRACT FROM AUTHOR]

The temperature-humidity index ( THI) is widely used to characterize heat stress in dairy cattle. Diet composition is known to induce variation in metabolic-associated heat production. However, the relationships between THI and diet are poorly characterized with regard to performance and intake behaviour. Therefore, the objectives were to evaluate the impact of THI on water intake ( WI), dry matter intake ( DMI) and the frequency of drinking and feeding bouts in lactating dairy cows offered four dietary treatments: each contained 20% grass silage and additionally (i) 20% maize silage, 60% concentrate (M- HC); (ii) 60% maize silage, 20% concentrate (M- LC); (iii) 20% pressed beet pulp silage, 60% concentrate ( BPS- HC); or (iv) 60% pressed beet pulp silage, 20% concentrate ( BPS- LC) ( DM basis). Individual WI and DMI were recorded from April to July 2013. Furthermore, dietary effects on milk production and reticular pH were estimated. Milk yield was lowest for M- LC, while energy-corrected milk was similar for all diets. Milk fat percentage was higher and milk protein amount lower for cows offered both LC diets. Reticular pH below 6.3, 6.0 and 5.8 lasted longest for BPS- LC. WI was higher for HC diets. However, the frequency of drinking bouts was not influenced by the ration. Lower DMI occurred for BPS- LC compared to M- LC. Frequency of feeding bouts was significantly higher for LC diets. THI was significantly related to WI, DMI as well as drinking and feeding bouts. Per increasing THI, WI increased slightly more for LC diets and DMI decreased more for HC diets. Frequency of drinking bouts increased slightly higher for BPS rations per rising THI, while the decrease in feeding bouts was highest for M- HC. In conclusion, TMR composition and moderate heat stress impacted WI and DMI of dairy cows, while both dietary energy density and ruminal filling might intensify the THI impact. [ABSTRACT FROM AUTHOR]

We studied the constancy of the relationship between rectal and intraabdominal temperature as well as their linkage to inflammatory markers (leucocyte counts, kynurenine-to-tryptophan ratio (Kyn-Trp ratio), tumour necrosis factor alpha ( TNF- α) in healthy and in pigs exposed to lipopolysaccharide ( LPS) and/or deoxynivalenol ( DON). Barrows ( n = 44) were fed 4 weeks either a DON-contaminated (4.59 mg DON/kg feed) or a control ( CON) diet and equipped with an intraabdominal temperature logger and a multicatheter system ( V.portae hepatis, V.lienalis, Vv.jugulares) facilitating infusion of 0.9% NaCl ( CON) or LPS (7.5 μg/kg BW) and simultaneous blood sampling. Body temperatures were measured and blood samples taken every 15 min for leucocyte counts, TNF- α and Kyn-Trp ratio. Combination of diet and infusion created six groups: CON_ CONjug.- CONpor., CON_ CONjug.- LPSpor., CON_ LPSjug.- CONpor., DON_ CONjug.- CONpor., DON_ CONjug.- LPSpor., DON_ LPSjug.- CONpor.. The relationship between both temperatures was not uniform for all conditions. Linear regression revealed that an intraabdominal increase per 1°C increase in rectal temperature was ~25% higher in all LPS-infused pigs compared to NaCl-infusion, albeit diet and site of LPS infusion modified the magnitude of this difference. Inflammatory markers were only strongly present under LPS influence and showed a significant relationship with body temperatures. For example, leucocyte counts in clinically inconspicuous animals were only significantly correlated to core temperature in DON-fed pigs, but in all LPS-infused groups, irrespective of diet and temperature method. In conclusion, the gradient between body core and rectal temperature is constant in clinically inconspicuous pigs, but not under various pathophysiological conditions. In the latter, measurement of inflammatory markers seems to be a useful completion. [ABSTRACT FROM AUTHOR]

The periparturient period is accompanied by metabolic and oxidative stress. Niacin is known to decrease lipolysis but is also reported to have anti-oxidative effects. Therefore, we examined the effects of energy supply and a nicotinic acid ( NA) supplementation on anti-oxidative serum parameters and on the expression of oxidative stress-related genes in blood leucocytes of periparturient dairy cows, differing in parity. Twenty-nine pluriparous and 18 primiparous cows were allocated to four different feeding groups 42 days before expected parturition until 100 days postpartum and fed a ration with either a low concentrate proportion of 30% ( LC) or a high concentrate proportion of 60% ( HC). After parturition, all animals received 30% concentrate which was increased to 50% either within 16 ( LC group) or 24 days ( HC group). Half of the animals per group were supplemented with 24 g NA per day from 42 days prepartum until 24 days postpartum. All investigated parameters varied significantly over time compared to parturition ( p < .05). Ferric reducing ability ( FRA) exhibited a nadir before parturition, and the antioxidant enzymes glutathione peroxidase ( GPX) and superoxide dismutase ( SOD) showed peak activities around parturition. Expression levels of GPX1, SOD2, xanthine dehydrogenase ( XDH) and nuclear factor (erythroid-derived 2)-like 2 ( NRF2) peaked before calving. The concentrate level influenced GPX activity and mRNA abundance of SOD2, XDH and poly ( ADP-ribose) polymerase 1 ( PARP1). Pluriparous animals exhibited higher serum GPX activities, a more distinct nadir for FRA and higher expression levels for GPX1, SOD2 and XDH. Primiparous cows displayed higher serum SOD activities. NA supplementation increased serum SOD activity antepartum in LC animals. Parturition was characterised by an increased need for antioxidants and an increased expression of oxidative stress-related genes that clearly differed with parity and was influenced by energy supply while NA exerted only minor effects on the investigated parameters. [ABSTRACT FROM AUTHOR]

The impact of technical feed treatment and diet on stomach lesions and traits of the local and systemic immune system were investigated in fattening pigs. Feeding groups differed in technical feed treatment (standard ground meal vs. finely ground and pelleted feed) and diet (soya bean meal vs. rapeseed meal/ DDGS/soya beans). Pigs were fattened approximately 10 weeks by ad libitum feeding and slaughtered subsequently. Gastric alterations were assessed by a macroscopic scoring system [macroscopic stomach score ( MSC) 0 = normal to 4 = severe lesions]. For immunological investigations, lymphocytes from blood and jejunal tissues were isolated. T-cell phenotyping was carried out by staining intestinal lymphocytes with monoclonal antibodies for CD4 and CD8 and flow cytometric measurements. MSC was higher in animals fed finely ground and pelleted feed compared with their counterparts. Significant interactions between diet and feed treatment considering the MSC were observed (p = 0.027). There was no effect of diet or technical feed treatment on T cells of blood, Lymphonodi gastrici or lamina propria ( LP) and intraepithelial cells. However, technical feed treatment significantly affected subsets of CD4+, CD8+, CD8low, CD4/ CD8 double-positive T cells, the mean fluorescence intensity of CD4+ T cells and the ratio of CD8low/ CD8high T cells in Peyer's patches ( PP). All named parameters were reduced in PP of animals fed finely ground and pelleted feed compared with animals fed standard ground meal. Furthermore, significant differences between T cells of lymph nodes and LP were observed between animals with middle MSC ( MSC = 1-2.5) and animals with high MSC ( MSC = 3-4). Significant alterations in T cells of PP were observed between animals of low ( MSC = 0-0.5) and high MSC. The observed effects provide the evidence that the impact of technical feed treatment is not limited on the stomach lesions. Possible stimuli and consequences of the immune system should be studied in more detail. [ABSTRACT FROM AUTHOR]

Due to its decisive function in the avian metabolic, endocrine and immune system L-arginine (Arg) is dietary indispensable for chickens. In 12-week-old cockerels of two high- and two low-performing purebred layer lines, the effects of increasing dietary Arg on the haematological and febrile response were studied over 48 h after single lipopolysaccharide ( LPS) injection. The offered diets contained Arg equivalent to 70%, 100% and 200% of recommended supply. Pathophysiological alterations in weight gain, feed intake, body temperature and differential blood count were examined in comparison with their physiological initial values. Within the first 24 h after LPS injection, cockerels reduced feed intake and lost body weight subsequently. Thereby, low-performing genotypes lost body weight to a lesser extent than high-performing ones. The loss of body weight was further intensified by deficient dietary Arg. Within the following 24 h, cockerels recovered by improving feed intake and weight gain. Furthermore, LPS induced genotype-specific fever response: both brown genotypes showed initial hypothermia followed by longer lasting moderate hyperthermia, whereas the white genotypes exhibited biphasic hyperthermia. Fever response was accompanied by significant changes in differential blood counts. Characterized by lymphopenia and heterophilia, a severe leucopenia was observed from 4 to 8 h after LPS injection and replaced by a marked leucocytosis with longer lasting monocytosis up to 48 h after LPS injection. Under given pathophysiological conditions, deficiently Arg-supplied cockerels showed higher total leucocyte counts than adequately and excessively Arg-supplied cockerels. However, deficient and surplus dietary Arg tended to cause higher ratios between heterophils and lymphocytes. To conclude, present results confirmed that LPS induced numerous immunological changes in 12-week-old cockerels and emphasized that chicken's genotype is a source of variation to be considered for immunological studies. Deficient dietary Arg intensified acute changes in differential blood counts and weight gain during LPS-induced inflammation. [ABSTRACT FROM AUTHOR]

Using a model to generate experimental groups with different manifestations of post-partum (p.p.) fat mobilization and ketogenesis, the effects of a dietary and a medical intervention on biochemical and haematological parameters, antibody titre, leucocytes subsets and function of transition cows were examined. In total, 60 German Holstein cows were allocated 6 weeks antepartum (a.p.) to 3 high-body condition score ( BCS) groups ( BCS 3.95) and 1 low- BCS group ( LC, BCS 2.77). High- BCS cows received a monensin controlled-release capsule ( HC/ MO) or a blend of essential oils ( HC/ EO) or formed a control group ( HC). Parameters were evaluated in 3 periods (day (d) −42 until calving, 1 until 14 days in milk ( DIM), 15 until 56 DIM). Over the course of trial, various parameters were influenced by period with greatest variability next to calving. White blood cell count was higher in the HC (8.42 × 103/ μl) and HC/ EO (8.38 × 103/ μl) groups than in the HC/ MO group (6.81 × 103/ μl) considering the whole trial. Supplementation of monensin decreased aspartate aminotransferase in comparison with the HC group similar to LC treatment. Bilirubin concentration was nearly doubled in all high- BCS cows in period 2. In period 3, essential oils increased γ-glutamyltransferase (80.4 Units/l) in comparison with all other groups and glutamine dehydrogenase (61 Units/l) in comparison with the LC (19 Units/l) and the HC/ MO group (18 Units/l). Results suggest that parameters were generally characterized by a high variability around calving. Based on biochemical characteristics, it appeared that the HC cows seemed to have compromised hepatocyte integrity when compared to the LC cows. From the immune parameters investigated, the BVDV antibody response was more pronounced in HC/ MO compared to HC/ EO. [ABSTRACT FROM AUTHOR]

The study aimed to examine the influence of supplemented conjugated linoleic acids ( CLA) to periparturient cows receiving different concentrate proportions antepartum on rumen pH (RpH) and rumen temperature ( RT). Twenty pregnant German Holstein cows were equipped with rumen probes for continuous RpH and RT measurement in a frequency of 15 min to investigate effects of dietary concentrate and CLA around parturition and the impact of parturition itself on RpH and RT. Cows had ad libitum access to partial mixed rations, 3 weeks prior to calving until day 7 post-partum. Antepartum, cows received 100 g/day control fat (CON) or CLA supplement, either in low (20%; CON-20, CLA-20) or high concentrate diet (60%; CON-60, CLA-60). Post-partum, concentrate proportion was adjusted to 50% while fat supplementation continued. Compared with adapted feeding, high concentrate proportions antepartum tended to increase DMI and reduced RpH. Groups CON-60 and CLA-60 spent more than 4 h per day below RpH 5.6 during late pregnancy, indicating the presence of subacute rumen acidosis ( SARA). The RT remained unaffected antepartum. Before calving, cows spent less time below RpH 5.6 and SARA could be detected in each group post-partum. Mean RpH increased slightly antepartum, whereas few hours before parturition a sharp decrease in RpH could be observed, accompanied with increased RT. Overall, it seems that CLA supplementation influences RpH and RT. Bearing in mind that rumen parameters fluctuate during day and herd level must be known, rumen probes for continuous RpH and RT measurement could be a useful management tool for animal health surveillance and may also help to predict parturition. [ABSTRACT FROM AUTHOR]

The aim of the present trials was to determine the effect of an experimental Brown-midrib ( Bm) corn hybrid in relation to a commercial corn hybrid ( Con) on digestibility in wethers and on dry matter intake ( DMI), milk yield and milk composition in dairy cows. Digestibility of crude fibre ( CF), neutral detergent fibre ( NDFom) and acid detergent fibre ( ADFom) were higher for Bm ( CF Con: 57.8%; Bm: 67.2%; NDFom Con: 56.8%; Bm: 64.8%; ADFom Con: 52.0%; Bm: 63.9%), but concentration of net energy for lactation did not differ ( Con: 6.4 MJ/kg DM; Bm: 6.3 MJ/kg DM). A total of 64 lactating German Holstein cows were assigned to one of the two dietary treatments Con or Bm according to milk yield, lactation number, days in milk and live weight. In Trial 1, cows were fed a total mixed ration consisting of 50% corn silage ( Con or Bm) and 50% concentrate on dry matter ( DM) basis. In Trial 2, the same animals were fed the respective silage for ad libitum intake and 5.3 kg of concentrate DM per animal per day. In Trial 1, DMI and milk-fat content were decreased significantly for the Bm-treatment ( DMI Con: 22.5 kg/day; Bm: 21.5 kg/day; milk fat Con: 3.8%; Bm: 3.3%). In Trial 2, milk yield and fat-corrected milk ( FCM) were increased significantly, whereas milk-fat% was decreased significantly (milk yield Con: 25.8 kg/day; Bm: 29.4 kg/day; FCM Con: 27.2 kg/day; Bm: 29.6 kg/day; fat Con: 4.4%; Bm: 4.0%). Diets did not influence ruminal p H or temperature. Diets, furthermore, did not influence rumination in either trial. Additional research on digestibility and rumen fermentation should, however, be carried out using dairy cows at respective intake levels as trials with wethers cannot be transferred to high-yielding ad libitum fed cows. [ABSTRACT FROM AUTHOR]

The aims of this study were to examine the effects of and possible interactions between dry matter (DM) intake and feeding Fusarium toxin-contaminated wheat on ruminal fermentation, serum chemical parameters and milk yield of dairy cows. Fourteen dairy cows equipped with ruminal and duodenal cannulas were analysed. All animals were fed the same ration, the daily feed amounts being adjusted to current performance. On DM basis, the ration consisted of 60% concentrate including 55% wheat [ Fusarium-contaminated wheat (mycotoxin period) or control wheat (control period)] and was completed with 40% maize and grass silage. Each cow was fed the contaminated wheat [deoxynivalenol (DON), 8.21 mg/kg DM and zearalenone (ZON), 0.09 mg/kg DM] and the control wheat (0.25 mg DON/kg DM and 51 μg ZON/kg DM). As expected, a higher organic matter (OM) intake decreased the amounts of fermented crude nutrients related to the respective intakes. An increased amount of crude protein degraded (p < 0.05) and a lower molar percentage of propionate in the rumen fluid were observed when feeding the Fusarium toxin-contaminated wheat at increased OM intakes in comparison with the control wheat. The activities of serum aspartate aminotransferase (ASAT; p < 0.001), glutamate dehydrogenase (GLDH; p < 0.01) and gamma glutamyl transferase ( γ-GT; p < 0.01) increased with increasing OM intake and were not related to the mycotoxin contamination of the wheat. [ABSTRACT FROM AUTHOR]

The aim of the present study was to examine the effects of feeding Fusarium toxin-contaminated wheat to dairy cows on nutrient utilization in the rumen and on duodenal flow of deoxynivalenol (DON), zearalenone (ZON) and their metabolites. Six dairy cows fitted with a large rumen cannula and a simple T-shaped cannula at the proximal duodenum was used in two experiments. The experiments included a control period in which the uncontaminated control wheat was fed and a period in which the control wheat was replaced by the Fusarium toxin-contaminated wheat (8.05 and 7.15 mg DON/kg and 0.26 and 0.1 mg ZON/kg in Expts 1 and 2 respectively). The wheat portion of the daily ration amounted to 50% on a dry matter (DM) basis and rations were completed with hay or grass silage. Five of the six cows were non-lactating and the total daily DM-intake ranged between 4 and 12 kg. The pH-values and the concentration of volatile fatty acids in ruminal fluid were not significantly influenced by feeding the contaminated wheat. In contrast, the postprandial ammonia concentration was consistently higher when the mycotoxin-contaminated wheat was fed. Moreover, the flow of microbial protein and utilizable protein at the duodenum were reduced at the same time. The concentrations of DON and ZON and of their metabolites in freeze-dried duodenal digesta were either not detectable or negligible during the control periods whereas distinct concentrations were measured during the periods where the contaminated wheat was fed. DON was nearly completely metabolized to de-epoxy-DON and the flow at the duodenum ranged between 4% and 28% of DON-intake. The ZON metabolites α-zearalenol (ZOL) and β-ZOL were recovered at the duodenum beside the parent toxin ZON. Their recovery as a percentage of ZON-intake ranged between 43% and 132%. In conclusion, feeding of Fusarium toxin-contaminated wheat altered the ruminal protein utilization. The question of whether this effect was a result of the mycotoxin being present in the rumen or of Fusarium growth-related structural (cell wall) changes of the wheat grain needs to be clarified. The low recovery of DON at the duodenum would indicate either a nearly complete degradation of the molecule in the rumen or an absorption by the mucosa of the rumen, whereas the higher ZON recovery would suggest a lower degradation of the parent toxin in the rumen and/or recovery of some bile-originating entero-hepatic cycling ZON/metabolites. [ABSTRACT FROM AUTHOR]

Two feeding experiments with female weaned piglets were carried out applying a complete two by two factorial design to investigate the effects of the dietary inclusion of 500 g/kg Fusarium toxin contaminated maize (8.6 mg/kg deoxynivalenol (DON); 1.2 mg/kg zearalenone (ZON)) and of 4 g/kg aluminosilicate (AS) as a detoxifying agent. The resulting four diets were fed ad libitum to a total of 80 piglets (20 piglets per group, allotted to a total of 20 pens) covering a live weight range of 10.5 ± 1.3 to 27.5 ± 4.4 kg in experiment 1, and to a total of 48 piglets (12 piglets per group, allotted to 12 pens) covering a live weight range of 9.7 ± 1.8 to 21.4 ± 4.8 kg in experiment 2. The animals of experiment 1 were slaughtered on days 34–36 of feeding the experimental diets. The mycotoxin analyses revealed that the control maize also contained considerable concentrations of Fusarium toxins, but the differences in DON and ZON concentrations between control and contaminated diets were sufficiently high to demonstrate both dose-related toxin effects. Voluntary feed intake and live weight gain of the animals were significantly reduced by the inclusion of Fusarium toxin contaminated maize into the diets in both experiments, while a significantly decreased feed to gain ratio was found in experiment 1. Furthermore, the relative weight of the uterus, stomach and heart of the animals fed the contaminated maize containing diets were significantly increased. Serum albumin concentrations and the activity of GLDH were significantly reduced by the inclusion of the contaminated maize. The addition of AS to the Fusarium toxin contaminated diets did not prevent or alleviate any of the mentioned effects. Moreover, the feed intake tended to be decreased by this supplementation in both experiments, while a significantly decreased feed to gain ratio was indicated for this factor in experiment one as well. The serum concentration of albumin and the activities of ASAT and γGT were significantly increased if AS was present in the diets while serum concentration of cholesterol and α-tocopherol were decreased significantly or in tendency, respectively. The concentrations of retinol and retinyl esters in liver and serum were not altered by the treatments. The analysed concentrations of zearalenone (ZON) and its metabolites in the bile fluid clearly indicated the differences in dietary ZON concentrations and showed that AS was ineffective in preventing the absorption of the toxin from the gastrointestinal tract. Also, serum concentrations of DON reflected the DON intake prior to sampling. However, there were no differences between groups fed diets with or without AS which also suggests the inefficacy of the tested AS in preventing the DON absorption. The present investigations failed to demonstrate a detoxifying capacity of the tested additive and emphasize the general necessity for a critical verification of detoxifying agents in vivo. [ABSTRACT FROM AUTHOR]

The fate of a single bolus of the Fusarium mycotoxin zearalenone (ZON) given intravenously to pigs was followed up. Pigs were equipped with duodenal re-entrant cannulas, post-valvular T-shape cannulas and with a urinary bladder balloon catheter. The animals were divided into three groups. Pigs of the control group were injected with ZON (Co), and pigs of the second group were also injected with ZON but their duodenal digesta was quantitatively exchanged for 12 h with corresponding pigs of the third group, not injected with ZON. Therefore, the second group had a disrupted entero-hepatic cycling of ZON (DEHC) and the third one had an induced entero-hepatic cycling of ZON (IEHC). The kinetic profile of ZON and its metabolites in plasma and their flow with urine, duodenal and ileal digesta and with faeces was examined over the next 72 h after the bolus was given. Eleven days later, pigs were slaughtered for collection of bile, urine and liver to analyse ZON residues. In all specimens examined, α-zearalenol (ZOL) was detected as the only metabolite of ZON. Kinetic evaluation of the plasma data revealed that the terminal elimination half-life of ZON was reduced from 2.63 h in pigs of Co-group to 1.1 h when EHC of ZON was disrupted for 12 h (DEHC-group). The maximum ZON concentration in plasma of pigs with the IEHC was found at 2.73 h after the bolus was given to their counterparts. The percentage of the α-ZOL- and ZON-area under the curves ( AUC) estimated for the IEHC-group amounted to approximately 18% of the corresponding AUC of the Co-group which would suggest that a substantial proportion of both substances are re-cycled via entero-hepatic re-circulation. Cumulative recovery of ZON and α-ZOL, expressed as percentage of the ZON-bolus was characterized by a saturation kinetics in urine and duodenal digesta, and after 72 h, the respective values for Co-, DEH-, and IEHC-groups were 70%, 55% and 12%; and 35%, 22% and 11%. Faecal excretion started to increase steeply after 48 h and still continued to increase after 72 h when the cumulative excretion was 6%, 3% and 2% for Co-, DEHC- and IEHC-groups respectively. Fourteen days after the bolus injection, ZON and α-ZOL concentrations in bile, liver and urine were lower than the detection limits of the applied method. The results would suggest that within this period of time a massive single bolus of ZON is nearly completely eliminated from the body. [ABSTRACT FROM AUTHOR]

Three diets containing either no supplemented fat (LF), 12% soybean oil (SO) or 12% coconut oil (CO) were fed to broilers to examine energy utilization in two experiments. Heat production and energy retained as fat and protein were measured in the first experiment using a respiration technique in combination with C- and N-balance and controlled (pair-fed) feeding conditions. Growth performance, carcass composition, chemical body composition and total body electrical conductivity (TOBEC) were evaluated in a second experiment under ad libitum feeding conditions (from hatching to day 35). Moreover, each of the three diet types was tested with or without the addition of a xylanase-containing enzyme preparation in the growth experiment. Energy utilization (experiment 1), expressed as the ratio between total retained energy and metabolizable energy intake, amounted to 0.33, 0.36 and 0.39 in LF-, SO- and CO-fed groups, respectively. Applying ad libitum feeding conditions in the second experiment caused a significant reduction in feed intake and weight gain in broilers fed the CO-diet. The feed-to-gain ratio was significantly lower in birds given the fat-supplemented diets. The highest degree of fatness as indicated by the highest percentage of abdominal and visceral fat and by highest total fat content was found in birds fed the CO-diet. The higher the body protein content and the lower the body fat content, the higher the TOBEC value should be. This was confirmed when LF-fed broilers were compared to their CO-fed counterparts. However, fat type seemed to be related to TOBEC values since SO-fed broilers had similar TOBEC values as CO-fed birds, whereas chemical body composition was comparable to LF-fed broilers. Xylanase addition significantly increased weight gain up to 21 days of age and decreased the feed-to-gain ratio slightly, whereas none of the other parameters were influenced by this treatment. An interaction between energy source and enzyme supplementation was... [ABSTRACT FROM AUTHOR]

Summary In this study, the effect of Fusarium toxin-contaminated triticale (FUS) at high (60%) and low (30%) concentrate proportion in ruminant rations on ruminal fermentation, microbial protein synthesis and digestibility was investigated, using in vivo and in vitro methods. Significant effects of the forage-to-concentrate ratio on ruminal degradation and digestibility of crude nutrients and detergent fibre fractions as well as on the pH value and the concentration of short chain fatty acids (SCFA) in rumen fluid were found. The production of SCFA was affected, and the degradation of crude fibre and neutral detergent fibre in the rumen was reduced by the inclusion of FUS at high concentrate proportion. The efficiency of microbial crude protein synthesis was higher in diets with 60% than in diets with 30% concentrates, but was impaired in the presence of FUS in vitro at the high concentrate level. Marginal effects of FUS on the amino acid pattern of microbial protein were detected. It was concluded that the use of FUS in high concentrate diets can influence ruminal fermentation and microbial protein synthesis at a dietary deoxynivalenol concentration below 5 mg/kg dry matter. [ABSTRACT FROM AUTHOR]