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The aim of the study was to investigate the effects of substituting silage of chopped grass with pulp silage of grass fractionated once or twice in a biorefinery using a screw press on fiber kinetics, protein value, and production of CH 4 in dairy cows. Six lactating multiparous Holstein cows in mid-lactation (176 ± 93 d in milk), cannulated in the rumen, duodenum, and ileum, were used in an incomplete 6 × 4 Latin square design with a 2 × 3 factorial arrangement of treatments. Perennial ryegrass was harvested in third regrowth from the same field at early and late developmental stage (35 and 44 d of regrowth, respectively) and subjected to 1 of 3 types of processing within each developmental stage. Grass was either harvested for normal silage making (mowed, wilted, chopped, and ensiled), or harvested fresh and fractionated using a screw press. Half of the pulp from the first fractionation was ensiled, whereas the other half of the pulp was rehydrated, fractionated a second time, and pulp hereof was ensiled. The grass and pulp silages were used with concentrates (65:35 forage to concentrate ratio) to make total mixed rations (TMR) based on either silage of chopped grass (GS), pulp silage of grass fractionated once (1×P), or pulp silage of grass fractionated twice (2×P), harvested either at early (E) or late (L) developmental stage resulting in 6 different TMR treatments (EGS, E1×P, E2×P, LGS, L1×P, L2×P). The TMR were fed for ad libitum intake and samples of intestinal digesta and feces were collected for determination of digestibility. The effect of processing on ash-free neutral detergent fiber (aNDFom) concentration in silages depended on developmental stage, but showed that within each developmental stage, pulp silage of grass fractionated twice had higher aNDFom concentration than pulp silage of grass fractionated once and silage of chopped grass. The 2×P resulted in lower (14.9 ± 0.55 vs. 17.5 ± 0.54 kg/d) dry matter intake (DMI) compared with GS. The effects of processing and developmental stage interacted such that apparent total-tract aNDFom digestibility was higher (784 ± 13 vs. 715 ± 13 g/kg) for L2×P compared with LGS, whereas no difference was found between E2×P and EGS. Moreover, the protein value was higher (106 ± 5 vs. 92 ± 5 g AA digested in the small intestine/kg of DMI) for 2×P compared with GS. Unexpectedly, processing had no effect on fractional rate of digestion of digestible aNDFom or CH 4 yield (L/kg of DMI), whereas feeding forages harvested at early compared with late developmental stage resulted in lower CH 4 yield. Feeding pulp silage of grass fractionated once generally yielded results intermediate to cows fed silage of chopped grass and pulp silage of grass fractionated twice. This study showed that pulp silage of fractionated grass could serve as feed for dairy cows because the fiber digestibility and protein value improved, but further research investigating effects of physical processing of forage on fiber kinetics is required. [ABSTRACT FROM AUTHOR]

In cattle, there are 2 significant forms of vitamin D: ergocalciferol (ERG) from fungi on roughage and cholecalciferol (CHO) from vitamin supplements or endogenous synthesis in the skin. The hypothesis of the present study is that vitamin D from the 3 sources is transported in different plasma fractions in the body. This is hypothesized to explain the lower efficiency of ERG compared to CHO in securing a sufficient plasma status of 25-hydroxyvitamin D and explain the inefficient excretion of dietary CHO into milk compared to endogenous CHO. Twenty vitamin D–depleted cows were assigned to 5 treatments: D2, housed indoor and fed 625-μg/d (25.000 IU) ERG; D3, housed indoor and fed 625-μg/d CHO; D2+D3, housed indoor and fed 625-μg/d ERG and 625-μg/d CHO; SUN, let out for daily pasture to facilitate CHO synthesis from sunlight; and D2+SUN, fed 625-μg/d ERG and let out for daily pasture. Blood samples were taken twice weekly and plasma fractionated by ultracentrifugation into 3 fractions: light lipoprotein (LLP), heavy lipoprotein (HLP), and protein and analyzed for content of ERG and CHO and their liver derived metabolites 25-hydroxyergocalciferol (25ERG) and 25-hydroxycholecalciferol (25CHO), respectively. Liver biopsies were taken on the last day of the study to asses gene expression related to vitamin D metabolism. During 4 wk of study, the vitamin D status in plasma increased to 19.3 to 22.8 ng/mL 25ERG in ERG-treated cows with the highest concentration in D2 ( P ≤ 0.05) and to 25.0 to 33.4 ng/mL 25CHO in pasture or CHO-treated cows with the highest concentration in SUN ( P ≤ 0.01). In plasma fractions, CHO was mainly found in the HLP fraction, whereas 25CHO was almost exclusively found in the protein fraction, probably due to its reported high binding affinity to vitamin D–binding protein. About 70% to 90% of 25ERG was found in the protein fraction and the remaining 25ERG was found in HLP, whereas ERG was found in both HLP and LLP fractions. In liver tissue, the expression of vitamin D-25-hydroxylase was lower in D2+D3 ( P ≤ 0.05) and SUN ( P ≤ 0.05) than that in the remaining groups, and the vitamin D receptor was expressed in the liver to a larger extent in D2+SUN than that in D2+D3 ( P ≤ 0.05) and SUN ( P ≤ 0.05). In conclusion, different plasma transport mechanisms may explain the lower physiological efficiency of ERG compared to CHO in securing the vitamin D status in plasma but do not explain the lower efficiency of synthetic CHO compared to endogenous CHO from sunlight or UV light in securing a high CHO content in milk. [ABSTRACT FROM AUTHOR]

• Calves often have a low plasma vitamin E concentration after weaning. • The current recommended level and type of vitamin E is insufficient. • 200 mg/kg of natural vitamin E on alcohol form is an effective dose. • Vitamin E supplementation had no effect on growth performance. • It is possible to produce a starter pellet with natural vitamin E on alcohol form. Calves often face a lower plasma vitamin E level than the recommended level (3 µg/ml for adult cows) after weaning, a level which has been related to a good immune response. Two experiments were performed to determine the most effective source and level of vitamin E to be included in a calf starter to maintain the plasma vitamin E level above the recommended level after weaning. Experiment 1 (Exp 1) and experiment 2 (Exp 2) included a total of 32 and 40 calves, respectively, from 2 weeks before weaning until 2 weeks after weaning. In Exp 1, calves were orally injected a daily dose of different vitamin E sources including, no α-tocopherol (0 dose; Control), 200 mg/d of RRR-α-tocopherol (ALC), 200 mg/d of RRR-α-tocopheryl acetate (ACT), or 200 mg/d of all-rac -α-tocopheryl acetate (SYN). In Exp 2, a dose response study was carried out with 0, 60, 120, and 200 mg/kg of ALC in a pelleted calf starter. Final BW (100 ± 16 and 86 ± 11 kg) and average daily gain (956 ± 303 and 839 ± 176 g/d in Exp 1 and 2, respectively; mean ± SD) were unaffected by either source or level of α-tocopherol. In Exp 1, the plasma RRR-α-tocopherol level was affected by α-tocopherol source (P < 0.001), week (P < 0.001), and interaction between them (P < 0.001). At weaning time, the plasma RRR-α-tocopherol was 2.7, 2.1, 1.1, and 0.8 μg/ml in ALC, ACT, SYN, and Control, respectively. In Exp 2, the plasma α-tocopherol level was affected by ALC dose (P = 0.04), week (P < 0.001), and a tendency for an interaction between them was observed (P = 0.06). At weaning, a 36, 31, and 28% reduction in plasma α-tocopherol level was observed compared to the beginning of the experiment with 0, 60, and 120 mg/kg of ALC, respectively; however, with 200 mg/kg of ALC, a 9% increase in the plasma α-tocopherol level was observed. In addition, 200 mg/kg of ALC was able to maintain plasma α-tocopherol after weaning higher than the recommended level. The results showed that the ALC was the most efficient source of α-tocopherol supplementation to be used in a calf starter. In addition, the 200 mg/kg of ALC in the calf starter was the only effective dose to maintain the postweaning plasma vitamin E concentration at the recommended level after weaning and α-tocopherol similar to that observed before weaning. [ABSTRACT FROM AUTHOR]

• Highest half-life and lowest elimination rate was observed in RRR-α-tocopherol. • Mammary gland of cows discriminates toward RRR-α-tocopherol. • The majority of the Ʃ2S stereoisomers was found in the liver. • 2R-α-tocopherol stereoisomers were more equal distributed between liver and plasma. Among different stereoisomers of all-rac -α-tocopherol, 2R-stereoisomers have higher biological activities than their 2S-stereoisomers. Two experiments were conducted to study the pharmacokinetics of stereoisomers of all-rac -α-tocopherol and investigated the discrimination and distribution of α-tocopherol stereoisomers in plasma and milk as well as quantitative secretion into milk with lactating Holstein cows after a single dose intramuscular injection of 2.50 g of all-rac -α-tocopheryl acetate. The highest half-life (2.92/h) and lowest elimination rate (0.36/h) were found for RRR-α-tocopherol. After a single dose injection of all-rac -α-tocopherol, highest maximal daily increase (S max , 8.36 mg/day) and accumulation secretion (AS, 50.8 mg) were observed for milk RRR-α-tocopherol. The majority of the Ʃ2S stereoisomers were found in the liver 36 h post injection, while the 2R stereoisomers were more equal distributed between liver and plasma. The present findings showed a clear discrimination between RRR-α-tocopherol, synthetic 2R stereoisomers and Ʃ2S stereoisomers in milk and plasma of dairy cows. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effect of increasing dietary supplementation of crushed sunflower seed (CSS) in the diet of dairy cows on the fatty acid (FA) composition of phospholipids and sphingomyelin in milk, and on mammary transcription of genes that are important for sphingomyelin de novo synthesis. Four groups of 6 cows received diets supplemented with CSS at 0% (control), or 5, 10, or 15% of dry matter for a 5-wk experimental period. Milk samples and mammary biopsies were collected at the end of the experiment. Phospholipid concentration in milk fat decreased linearly with CSS supplementation. Sphingomyelin concentration in milk fat was unaffected by CSS supplementation. Daily yield of phospholipids decreased linearly with CSS supplementation. Daily yield of sphingomyelin was not significantly affected. The CSS supplementation linearly increased the proportion of monounsaturated FA in milk phospholipids. The major isomer incorporated into phospholipids was C18:1 (n-9 cis), which showed a linear increase with CSS supplementation. The C22:0 proportion in sphingomyelin increased linearly with CSS supplementation and constituted between 15.2 to 25.4% of total FA in sphingomyelin. However, CSS supplementation linearly decreased C23:0 sphingomyelin. Mammary transcription of serine palmitoyl transferase, long chain subunit 1 and subunit 2, the rate-limiting enzymes in ceramide synthesis, showed a linear decrease with increasing CSS supplementation. In conclusion, the data showed that dietary supplementation of CSS linearly increased the proportion of unsaturated FA and monounsaturated FA in milk phospholipids with no effect on phospholipid concentration. In addition, CSS supplementation linearly decreased n-3 polyunsaturated fatty acid proportion in sphingomyelin. The results further showed that mammary transcription of important genes for sphingomyelin de novo synthesis is regulated by lipid supplementation. [ABSTRACT FROM AUTHOR]

Highlights • Pulp from processing of grassland plants is a promising alternative source of forage for dairy cows. • The protein value of pulp was similar or increased compared to original plant. • The concentration of all essential amino acids increased in pulp compared to original plant. Abstract Biorefinery of grassland plants may enable the production of feed for both ruminants and monogastrics at the same time. The pulp fibre fraction from twin-screw processed white clover, red clover, lucerne, and perennial ryegrass, is a major side-stream commonly considered of low value. However, it maintains a crude protein (CP) fraction of which a high proportion is expected to be fibre-associated. The pulp is expected to be suitable as forage for ruminants but knowledge of the feed value is limited. The objectives of this study were to assess the protein degradation in the rumen and the protein value of pulp compared to the original plant material, and to study the protein distribution among fibre fractions in order to evaluate the pulp as a source of forage for dairy cows. The ash concentration in the pulp was 51.1–72.3 g/kg DM compared to 86.3–104 g/kg DM in the original plant, while the in vitro digestible organic matter (DOM) in dry matter (DM) did not decrease significantly in pulp (532–689 g/kg DM) compared to plant (564–694 g/kg DM). Neutral detergent fibre (aNDF) concentration was higher in pulp (529–694 g/kg DM) than in original plant (342–503 g/kg DM), while the CP concentration of the aNDF from pulp (77.8–186 g/kg aNDF) did not differ from the concentration found in the plant aNDF (74.7–137 g/kg aNDF). Furthermore, the total amino acid (AA) concentration increased in pulp (825 g/kg CP) compared to original plant (768 g/kg CP), and the individual concentration of all essential AA in DM increased. The in situ rumen degradation of CP showed that the potentially degradable fraction was not different between plant (889–953 g/kg) and pulp (817–939 g/kg), although the fractional rate of degradation was lower in the pulp (0.093–0.109 h−1) than in the plant (0.113–0.192 h−1). Thus effective degradability (ED) of CP was lower in pulp (579–647 g/kg) than in plant (657–786 g/kg) increasing rumen escape protein (REP). The intestinal digestibility of REP was similar, thus a higher proportion of the pulp CP (225–256 g/kg) was digested in the intestine compared to plant CP (125–190 g/kg). The indigestible neutral detergent fibre (INDF) proportion of aNDF was not different between plant (88.1–422 g/kg aNDF) and pulp (85.3–460 g/kg aNDF). This study demonstrated that pulp from twin-screw pressing of white clover, red clover, lucerne, and perennial ryegrass has a protein concentration and value for ruminants, which is similar to the original plant material. [ABSTRACT FROM AUTHOR]

The objective of the study was to quantify the effects on dry matter intake (DMI), nutrient digestibility, gas exchange, milk production, and milk quality in dairy cows fed fresh grass harvested at different maturity stages. Sixteen Danish Holstein cows in mid-lactation were divided into 4 blocks and used in 4 incomplete 4 × 2 Latin squares with 2 periods of 21 d. The cows received 1 of 4 treatments in each period, resulting in 8 cows per treatment, as follows: grass-clover silage supplemented with 6 kg/d concentrate pellets (SILc), fresh grass harvested at late maturity stage supplemented with 6 kg/d concentrate pellets (LATc), fresh grass harvested at late maturity stage (LAT), and fresh grass harvested at early maturity stage (ERL). The cows were housed in tiestalls and milked twice daily. The cows had ad libitum access to the forage, and concentrate pellets were divided into equal amounts and fed separately in the morning and afternoon. Fecal samples were collected to determine apparent total-tract digestibility, and samples of rumen fluid were collected for determination of short chain fatty acid composition. Halters were used for measuring eating and rumination time. Gas exchange was measured in open-circuit respiration chambers. Total DMI was higher in LATc and ERL (16.9 ± 0.45 and 15.5 ± 0.39 kg/d, respectively) compared with LAT (14.1 ± 0.42 kg/d). Relative to SILc, cows fed fresh grass experienced a convex pattern in DMI during the experiment. The changes in DMI were related to changes in leaf to stem ratio, fiber concentration, and organic matter digestibility determined in vitro in samples of the fresh grass harvested throughout the experiment. The apparent total-tract digestibility of organic matter was higher in SILc and LAT compared with LATc. Methane yield was lower for LATc compared with LAT (19.5 ± 0.61 vs. 22.6 ± 0.55 g of CH 4 /kg of DMI), and was not different between LAT and ERL. Compared with LAT, milk yield was higher for ERL (21.1 ± 1.14 vs. 23.4 ± 1.11 kg/d) and energy-corrected milk (ECM) yield was higher for LATc (21.5 ± 0.99 vs. 25.3 ± 1.03 kg/d). We detected no differences in milk or ECM yield between SILc and LATc. Milk protein yield was higher and milk fat concentration was lower in LATc compared with LAT. The fatty acid percentages of ∑C4-C14:1 and ∑C16 in milk were higher for SILc compared with LATc, signifying pronounced de novo synthesis. The n-6:n-3 ratio in milk fatty acids was lower for SILc and LAT compared with LATc, indicating improved nutritional quality for SILc and LAT. However, retinol concentration in milk was lower in SILc compared with all other treatments. The study implies that feeding silage instead of fresh grass has no effect on DMI, ECM yield, or CH 4 yield, and that concentrate supplementation can increase milk production, affects milk quality, and reduces the effect on climate, whereas feeding less mature grass increases DMI and milk yield, but has no effect on CH 4 yield. [ABSTRACT FROM AUTHOR]

Abstract: The present study was carried out to establish knowledge of consequence for setting up guidelines of importance for production of competitive organic pork of high quality. Performance and meat quality characteristics were compared between three organic pig production systems based on indoor housing with access to an outdoor area and a Danish conventional indoor system including 100% concentrate during the finishing feeding stage. The three organic systems used the following three feeding regimes: 100% organic concentrate according to Danish recommendations, 70% organic concentrate (restricted) plus ad libitum organic barley/pea silage and 70% organic concentrate (restricted) plus ad libitum organic clover grass silage, respectively. With exception of a slightly lower daily gain in organic pigs fed 100% concentrate, no significant difference was found in performance and meat quality characteristics compared with results obtained in the conventional system. In contrast and independent of roughage used, organic pigs raised on 70% concentrate had a significant reduction in daily gain (P <0.001) compared with pigs raised on 100% concentrate, despite the fact that no difference in feed conversion rate was seen between the tested production systems. However, the percentage of leanness increased significantly in meat from organic pigs raised on 70% concentrate plus roughage compared with meat from pigs given 100% concentrate. This was reflected in higher yield (weight) of lean cuts and lower yield of cuts with high fat content from pigs fed 70% concentrate plus roughage. In general, organic feeding resulted in a significantly higher content of polyunsaturated fatty acids in the back fat (1.8%), which increased further when restricted feeding plus roughage (4%) was used. Restricted concentrate feeding gave rise to a decrease in tenderness compared with pork from pigs fed 100% concentrate. [Copyright &y& Elsevier]

Discusses results of an experiment conducted on chickens that were fed a diet supplemented with a combination of ascorbic acid and alpha-tocopherol or oregano in order to ameliorate a negative effect of stress on meat quality characteristics. Tocopherol content in feed and muscle; Carotenoid content in oregano; Erythrocyte stability; Effect on activities of antioxidative enzymes.

The combination of a muscle glycogen reducing diet or a standard diet (control group) with normal (80 mg/kg) and high vitamin E levels (500 mg/kg) and exercise immediately prior to slaughter was used on 56 pigs to investigate the influence on meat quality indicators (pH and temperature) and attributes (drip loss, colour and Warner–Bratzler shear force). The drip loss was reduced in M. longissimus dorsi, M. biceps femoris and M. semimembranosus in pigs given the muscle glycogen reducing diet compared with the control groups, the greatest effect was seen in exercised pigs. These results can be explained by an early post mortem reduction in glycometabolism in pigs fed muscle glycogen reducing diets rather than by an increase in ultimate pH. Noticeably, high dietary vitamin E level increased muscle glycogen stores by about 10% on the day prior to slaughter but not on the day of slaughter in both dietary groups compared with the low dietary vitamin E level, which in fact reduced rather than improved the water-holding capacity, especially in pigs fed the standard diet. [Copyright &y& Elsevier]

The present study investigated the effect of a high proportion of different forage species in the diet, parity, milking time, and days in milk (DIM) on milk fatty acid (FA) profile, and transfer efficiency of C18:2n-6, C18:3n-3, n-6, and n-3 in dairy cows. Swards with perennial ryegrass [early maturity stage (EPR) and late maturity stage (LPR)], festulolium, tall fescue (TF), red clover (RC), and white clover (WC) were cut in the primary growth, wilted, and ensiled without additives. Thirty-six Danish Holstein cows in an incomplete Latin square design were fed ad libitum with total mixed rations containing a high forage proportion (70% on dry matter basis). The total mixed rations differed only in forage source, which was either 1 of the 6 pure silages or a mixture of LPR silage with either RC or WC silage (50:50 on dry matter basis). Proportion of C18:2n-6 in milk FA was affected by diet, and RC and WC diets resulted in the highest proportion of C18:2n-6 in milk FA (21.6 and 21.8 g/kg of FA, respectively). The highest and lowest milk C18:3n-3 proportion was observed in WC and LPR, respectively. In addition, WC diet resulted in highest transfer efficiency of C18:3n-3 from feed to milk (12.2%) followed by RC diet (10.7%), whereas EPR diet resulted in the lowest transfer efficiency of C18:3n-3 (3.45%). The highest milk proportion of cis -9, trans -11 conjugated linoleic acid (CLA) was observed in cows fed TF (3.20 g/kg of FA), which was 23 to 64% higher than the proportion observed in the cows fed the other diets. The highest α-tocopherol concentration (µg/mL) in milk was observed in EPR (1.15), LPR (1.10), and festulolium (1.06). Primiparous cows showed higher proportion of cis -9, trans -11 CLA (2.63 g/kg of FA) than multiparous cows (2.21 g/kg of FA). Cows early in lactation had a higher proportion of long-chain FA in milk than cows later in lactation, as long-chain FA decreased with 0.184 g/kg of FA per DIM, whereas medium-chain FA increased with 0.181 g/kg of FA per DIM. Proportion of C18:2n-6 in milk from evening milking was higher than in milk from morning milking (16.7 vs. 15.8 g/kg of FA). In conclusion, the results showed that milk FA profile of cows was affected by forage source in the diet, and RC and WC increased the health-promoting FA components, particularly n-3, whereas the TF diet increased proportion of CLA isomers in milk. Proportion of CLA isomers in milk FA from primiparous cows was higher than in milk from multiparous cows. In addition, evening milk contained more FA originating from diets compared with morning milk. [ABSTRACT FROM AUTHOR]