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... This proportion is even higher, if indirect energy use by agriculture in fertilisers, machinery, etc. ... Changes in soil carbon (C) storage and energy used for production of machinery and buildings are ... fold: (i) to present the... more
... This proportion is even higher, if indirect energy use by agriculture in fertilisers, machinery, etc. ... Changes in soil carbon (C) storage and energy used for production of machinery and buildings are ... fold: (i) to present the model, (ii) to analyse the effect of organic and conventional ...
Research Interests: Environmental Science, Carbon Dioxide, Biology, Organic Farming, Environmental Sciences, and 14 moreNitrogen, Methane, Greenhouse Gas Emissions, Greenhouse Gas, Greenhouse gases, Nitrous Oxide, Milk Yield, Management Practice, Crop Rotation, Dairy Farm, Manure Management, Metabolic energy, Regional Difference, and Organic Dairy Farming
This study was conducted to evaluate the effects of feeding molasses or maize grain with agro-processing by-products on yield and quality of meat from Tanzania shorthorn zebu (TSZ) cattle. Forty five steers aged 2.5 to 3.0 years with 200... more
This study was conducted to evaluate the effects of feeding molasses or maize grain with agro-processing by-products on yield and quality of meat from Tanzania shorthorn zebu (TSZ) cattle. Forty five steers aged 2.5 to 3.0 years with 200 ±5.4 kg body weight were allocated into five dietary treatments namely hominy feed with molasses (HFMO), rice polishing with molasses (RPMO), hominy feed with maize meal (HFMM), rice polishing with maize meal (RPMM) and maize meal with molasses (MMMO). Ad libitum amount of each dietary treatment and hay were offered to nine steers for 90 days. Cooking loss (CL) and Warner Bratzler shear force (WBSF) values were determined on M. longissimus thoracis et lumborum aged for 3, 6, 9 and 12 days. Steers fed on HFMO diet had higher (P < 0.05) nutrient intake (86.39 MJ/d energy; 867 g/d CP), weight gain (919 g/d) and half carcass weight (75.8 kg) than those fed other diets. Meat of steers from all diets was tender with average WBSF values of 47.9 Ncm −2 ....
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The aim of this study was to determine the effects of fatty acids and triglycerides composition on melting behavior of milk fat. The melting profiles, fatty acids composition and triglycerides composition of milk fat from 27 cows fed palm... more
The aim of this study was to determine the effects of fatty acids and triglycerides composition on melting behavior of milk fat. The melting profiles, fatty acids composition and triglycerides composition of milk fat from 27 cows fed palm oil, rapeseed oil and a low fat diet were analyzed. Correlations between individual fatty acids and triglycerides, and the melting offset temperatures of milk fat fractions were obtained using multivariate data analysis. Low fat feeding increased the proportion of short and medium chain fatty acids and decreased the proportion of long chain fatty acids. The opposite effect was observed in milk fat of cows from lipid supplemented diets. Palmitic and myristic acids correlated positively to the melting offset temperatures of high melting fraction of milk fat while oleic and linoleic acid had strong negative correlations. Furthermore, high molecular weight triglycerides contributed positively to the melting offset temperatures of high melting fraction ...
This study investigated the effect of forage quality on intake, eating and ruminating activities, faecal particle size distribution, and neutral detergent fibre (NDF) digestibility in three ruminating species. The experimental design... more
This study investigated the effect of forage quality on intake, eating and ruminating activities, faecal particle size distribution, and neutral detergent fibre (NDF) digestibility in three ruminating species. The experimental design included ad libitum feeding of three ruminating species with two types of forage for two periods in a crossover design. The species included six adult, non-pregnant female Danish Landrace
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Sadjad Danesh Mesgaran1 Björn Kuhla1 David Humphries2 Martin Weisbjerg3 Peter Lund3 Emer Kennedy4 Michael O'Donovan4 Michelle Liddane4 Norann Galvin4 Jan Dijkstra5 René Baumont6 Leibniz Institute for Farm Animal Biology (FBN),... more
Sadjad Danesh Mesgaran1 Björn Kuhla1 David Humphries2 Martin Weisbjerg3 Peter Lund3 Emer Kennedy4 Michael O'Donovan4 Michelle Liddane4 Norann Galvin4 Jan Dijkstra5 René Baumont6 Leibniz Institute for Farm Animal Biology (FBN), Dummerstorf, Germany University of Reading, Reading, United Kingdom Aarhus University, Tjele, Denmark Teagasc, Animal and Grassland Research and Innovation Centre, Fermoy, Ireland Wageningen University & Research, Wageningen, Netherlands Université Clermont Auvergne, INRAE, Saint-Genès-Champanelle, France
A nuclear magnetic resonance (NMR)-based approach was introduced for metabolic fingerprinting of 21 grass and legume cultivars in the present study. Applying principal component analysis (PCA) on the fingerprints obtained on water... more
A nuclear magnetic resonance (NMR)-based approach was introduced for metabolic fingerprinting of 21 grass and legume cultivars in the present study. Applying principal component analysis (PCA) on the fingerprints obtained on water extracts, it was possible to elucidate the variation between cultivars and the magnitude of changes in the metabolic fingerprint between the spring growth and the second regrowth. Consequently, the potential of the method for tracking differences and changes related to cultivar and season was demonstrated. In addition, partial least-squares (PLS) regressions revealed correlations between the NMR fingerprints and the value of the grasses as animal feed evaluated as concentration of sugars, neutral detergent fibres (NDF) (R = 0.82), indigestible neutral detergent fibres (iNDF) (R = 0.90), and in vitro organic matter digestibility (IVOMD) (R = 0.75). The correlations between these parameters and the NMR fingerprint could mainly be ascribed to differences in spectral intensities from signals assigned to malic acid (2.40 and 4.70 ppm), choline (3.27 ppm), and glucose (5.24 ppm), and the biochemical rationale for this relation is discussed.
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This paper reviews the effects of extended lactation (EXT) as a strategy in dairy cattle on milk production and persistency, reproduction, milk quality, lifetime performance of the cow and finally the economic effects on herd and farm... more
This paper reviews the effects of extended lactation (EXT) as a strategy in dairy cattle on milk production and persistency, reproduction, milk quality, lifetime performance of the cow and finally the economic effects on herd and farm levels as well as the impact on emission of greenhouse gas at product level. Primiparous cows are able to produce equal or more milk per feeding day during EXT compared with a standard 305-d lactation, whereas results for multiparous cows are inconsistent. Cows managed for EXT can achieve a higher lifetime production while delivering milk with unchanged or improved quality properties. Delaying insemination enhances mounting behaviour and allows insemination after the cow’s energy balance has become positive. However, in most cases EXT has no effect or a non-significant positive effect on reproduction. The EXT strategy sets off a cascade of effects at herd and farm level. Thus, the EXT strategy leads to fewer calvings and thereby expected fewer diseases...
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The major microbial fermentation of forages and production of volatile fatty acids (VFA) takes place in the medial part of the rumen, whereas the absorption of VFA occurs through the rumen epithelium, for example the ventral sac. The... more
The major microbial fermentation of forages and production of volatile fatty acids (VFA) takes place in the medial part of the rumen, whereas the absorption of VFA occurs through the rumen epithelium, for example the ventral sac. The objective was to study effects of forage neutral detergent fibre (NDF) content and time after feeding on the medial to ventral VFA and pH gradient as well as rumen motility in the rumen of heifers fed grass/clover silages. Four silages were harvested at different growth stages with NDF contents of 31–45% of DM and in vitro organic matter digestibilities of 75–82% and fed to four rumen-fistulated Jersey heifers at 90% of ad libitum level in a Latin square design, with half the ration fed at 0800 hours and 1530 hours. Rumen fluid was sampled hourly from 0730 hours to 1530 hours in the medial and ventral rumen, and analysed for pH and concentrations of VFA, L-lactic acid, and ammonia to assess ruminal chemical gradient. Reticular contractions were continuo...
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Methane constitutes a significant loss of feed gross energy in ruminants, and there is an ongoing struggle for identifying feed and animal characteristics feasible for documentation of National Greenhouse Gas Inventories. The aim of the... more
Methane constitutes a significant loss of feed gross energy in ruminants, and there is an ongoing struggle for identifying feed and animal characteristics feasible for documentation of National Greenhouse Gas Inventories. The aim of the current study was to develop a model that predicts the methane conversion factor (Ym, % of gross energy) for dairy cows on the basis of data obtained from a range of our respiration studies, and, subsequently, to use this model to predict Ym for Holstein and Jersey cows on the basis of compiled average national farm data on dry matter intake, yield of energy-corrected milk and dietary composition. In total, 183 observations were compiled, including 41 rations from 10 experiments with Holstein dairy cows where methane emission was measured by means of indirect calorimetry using the same experimental equipment. Two models were developed; one using dry matter intake and feed composition as variables, and one using yield of energy corrected milk and feed...
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The aim of this meta-analysis was to compare feed intake, milk production, milk composition and organic matter (OM) digestibility in dairy cows fed different grass and legume species. Data from the literature was collected and different... more
The aim of this meta-analysis was to compare feed intake, milk production, milk composition and organic matter (OM) digestibility in dairy cows fed different grass and legume species. Data from the literature was collected and different data sets were made to compare families (grasses v. legumes, Data set 1), different legume species and grass family (Data set 2), and different grass and legume species (Data set 3+4). The first three data sets included diets where single species or family were fed as the sole forage, whereas the approach in the last data set differed by taking the proportion of single species in the forage part into account allowing diets consisting of both grasses and legumes to be included. The grass species included were perennial ryegrass, annual ryegrass, orchardgrass, timothy, meadow fescue, tall fescue and festulolium, and the legume species included were white clover, red clover, lucerne and birdsfoot trefoil. Overall, dry matter intake (DMI) and milk produc...
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The effects of a 24-h administration of a ration high in nitrate (20 g/kg DM) on DM intake and enteric gas production in lactating dairy cows as well as the effect of different doses of nitrate on in vitro fermentation were studied.... more
The effects of a 24-h administration of a ration high in nitrate (20 g/kg DM) on DM intake and enteric gas production in lactating dairy cows as well as the effect of different doses of nitrate on in vitro fermentation were studied. Nitrate reduced in vivo methane (CH4) production by 31%, and CH4 production increased again when nitrate supplementation was stopped. A similar effect was found when relating CH4 to carbon dioxide, and to DM intake. Addition of nitrate was followed by increased hydrogen production, which decreased again when nitrate was stopped. Nitrate addition did not affect in vitro rumen fermentation in terms of DM degradability, pH, ammonia nitrogen, microbial protein and volatile fatty acid production, but it decreased gas production with longer initial delay time before onset of gas production and lower gas production rate. Nitrate added at 7–20 g/kg ration DM significantly decreased net initial (0–12 h) CH4 production by 10–16%, although no further depression was...
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The purpose of this experiment was to study the effect of the physical form of rapeseed fat on methane (CH4) mitigation properties, feed digestion, and rumen fermentation. Four lactating ruminal-, duodenal-, and ileal-cannulated Danish... more
The purpose of this experiment was to study the effect of the physical form of rapeseed fat on methane (CH4) mitigation properties, feed digestion, and rumen fermentation. Four lactating ruminal-, duodenal-, and ileal-cannulated Danish Holstein dairy cows (143 d in milk, milk yield of 34.3 kg) were submitted to a 4×4 Latin square design with 4 rations: 1 control with rapeseed meal (low-fat, CON) and 3 fat-supplemented rations with either rapeseed cake (RSC), whole cracked rapeseed (WCR), or rapeseed oil (RSO). Dietary fat concentrations were 3.5 in CON, 5.5 in RSC, 6.2 in WCR, and 6.5% in RSO. The amount of fat-free rapeseed was kept constant for all rations. The forage consisted of corn silage and grass silage and the forage to concentrate ratio was 50:50 on a dry matter basis. Diurnal samples of duodenal and ileal digesta and feces were compiled. The methane production was measured for 4 d in open-circuit respiration chambers. Additional fat reduced the CH4 production per kilogram...
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The physical structure value of conserved grass/clover forages of spring harvest was evaluated by assessing effects of harvest time, conservation method, iNDF/NDF ratio and NDF intake (NDFI) per kg BW on chewing activity and fecal... more
The physical structure value of conserved grass/clover forages of spring harvest was evaluated by assessing effects of harvest time, conservation method, iNDF/NDF ratio and NDF intake (NDFI) per kg BW on chewing activity and fecal particle size in dairy heifers. A mixed sward consisting of ryegrass (Lolium perenne), red clover (Trifolium pratense) and white clover (Trifolium repens) was harvested in 2009 on May 9 (early) and 25 (late), and both cuts were conserved as silage and hay. The early silage, early hay, late silage and late hay contained dry matter (DM) of 454, 842, 250 and 828 g/kg, and NDF of 315, 436, 414 and 503 g/kg DM, respectively. Forages were fed as sole feed to four Jersey heifers of 435±30 kg BW in a 4×4 Latin square experiment. Feeding level was 90% of individual ad libitum intake, divided equally across two daily meals offered at 0800 and 1530 h. Chewing activity was estimated from recorded jaw movements (JM) oscillations continuously logged for 96 h and summari...
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Starch is an important energy-providing nutrient for dairy cows that is most commonly provided from cereal grains. However, ruminal fermentation of large amounts of easily degradable starch leads to excessive production and accumulation... more
Starch is an important energy-providing nutrient for dairy cows that is most commonly provided from cereal grains. However, ruminal fermentation of large amounts of easily degradable starch leads to excessive production and accumulation of volatile fatty acids (VFA). VFA not only play a vital role in the energy metabolism of dairy cows but are also the main cause of ruminal acidosis and depressed feed intake. The aim of the present study was to compare maize cob silage (MCS) as an energy supplement in rations for dairy cows with highly rumen-digestible rolled barley and with sodium hydroxide wheat (SHW), which has a higher proportion of by-pass starch than barley. Two studies were carried out: (1) a production study on 45 Danish Holstein cows and (2) an intensive study to determine digestibilities, rumen fermentation patterns and methane emission using three rumen-cannulated Danish Holstein cows. Both studies were organised as a 3×3 Latin square with three experimental periods and t...
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Particle size alterations during neutral detergent fiber (NDF) determination and in situ rumen incubation were analyzed by dry sieving and image analysis to evaluate the in situ procedure for estimation of NDF degradation parameters and... more
Particle size alterations during neutral detergent fiber (NDF) determination and in situ rumen incubation were analyzed by dry sieving and image analysis to evaluate the in situ procedure for estimation of NDF degradation parameters and indigestible NDF concentration in terms of particle size. Early-cut and late-cut grass silages, corn silage, alfalfa silage, rapeseed meal, and dried distillers grains were examined. Treatments were (1) drying and grinding of forage samples and grinding of concentrates; (2) neutral detergent-soluble (NDS) extraction; (3) machine washing and NDS extraction; (4) 24-h rumen incubation, machine washing, and NDS extraction; and (5) 288-h rumen incubation, machine washing, and NDS extraction. Degradation profiles for potentially degradable NDF were determined and image analysis was used to estimate particle size profiles and thereby the risk for particle loss. Particle dimensions changed during NDF determination and in situ rumen incubation and variations ...
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The objective of this study was to investigate the transfer of volatile terpenes from caraway seed and oregano plant essential oils into cow's milk through respiratory and gastrointestinal exposure. Essential oils have potential... more
The objective of this study was to investigate the transfer of volatile terpenes from caraway seed and oregano plant essential oils into cow's milk through respiratory and gastrointestinal exposure. Essential oils have potential applications as feed additives because of their antimicrobial properties, but very little work exists on the transfer of their volatile compounds into milk. Lactating Danish Holstein cows with duodenum cannula were used. Gastrointestinal exposure was facilitated by infusing the essential oils, mixed with deodorized sesame oil, into the duodenum cannula. Two levels were tested for each essential oil. Respiratory exposure was facilitated by placing the animal in a chamber together with a sponge soaked in the essential oils. All exposures were spread over 9h. Milk samples were collected immediately before and after exposure, as well as the next morning. Twelve monoterpenes and 2 sesquiterpenes were analyzed in essential oils and in milk samples using dynami...
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Rumen passage kinetics of forage and concentrate fiber were analyzed to determine intrinsic feed effects and extrinsic ration effects on the retention time of fiber in the rumen. Sixteen Danish Holstein cows (557 ± 37 kg of body weight,... more
Rumen passage kinetics of forage and concentrate fiber were analyzed to determine intrinsic feed effects and extrinsic ration effects on the retention time of fiber in the rumen. Sixteen Danish Holstein cows (557 ± 37 kg of body weight, 120 ± 21 d in milk, mean ± SD), 8 fitted with ruminal cannulas, were used in a completely randomized block experiment. Treatments differed in forage type (corn silage vs. grass silage) and forage:concentrate ratio (50:50 vs. 75:25 on organic matter basis). Fiber passage kinetics were studied based on rumen evacuations and on marker excretion profiles in feces fitted to 1 and 2 pool models. Each cow received ytterbium (Yb)-labeled fiber of the forage fed in the ration, samarium (Sm)-labeled fiber of the forage not fed in the ration, and concentrate fiber labeled with lanthanum (La), all as a single pulse dose. Nineteen fecal grab samples were taken per cow. Rumen liquid passage was studied using chromium-EDTA dosed as a single pulse into the rumen, fo...
Research Interests: Dairy Science, Animal Production, Animal Feed, Female, Animals, and 9 moreDigestion, Poaceae, Cattle, Zea mays, Dietary fiber, Feces, Food Sciences, Rumen, and Silage
Methane is a greenhouse gas with a significant anthropogenic contribution from cattle production. A demand exists for techniques that facilitate evaluation of mitigation strategies for dairy cows. Therefore, a low-cost system facilitating... more
Methane is a greenhouse gas with a significant anthropogenic contribution from cattle production. A demand exists for techniques that facilitate evaluation of mitigation strategies for dairy cows. Therefore, a low-cost system facilitating the highest possible animal welfare was constructed and validated. The system uses the same principles as systems for open-circuit indirect calorimetry, but to lower the costs, the chamber construction and air-conditioning system were simpler than described for other open-circuit systems. To secure the highest possible animal welfare, the system is located in the cow's daily environment. The system consists of 4 transparent polycarbonate chambers placed in a square so that the cows are facing each other. The chamber dimensions are 183 (width), 382 (length), and 245 cm (height) with a volume of 17 m(3). Flow and concentrations of O(2), CO(2), CH(4), and H(2) are measured continuously in the outlet. Flow is measured with a mass flow meter, O(2) w...
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Milk fatty acid composition is influenced by a range of conditions such as breed, feeding, and stage of lactation. Knowledge of milk fatty acid composition of individual cows would make it possible to sort milk at farm level according to... more
Milk fatty acid composition is influenced by a range of conditions such as breed, feeding, and stage of lactation. Knowledge of milk fatty acid composition of individual cows would make it possible to sort milk at farm level according to certain fatty acid specifications. In the present study, 225 milk samples were taken from 84 cows in a herd equipped with an automatic milking system. Milk fat content varied depending on yield and time since last milking, whereas the milk fatty acid composition did not vary significantly within cow. It was concluded that random milk samples may be used for analysis of fatty acid composition.
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The main objective was to evaluate the potential of grass silages of very high quality to support a high milk yield with a low or moderate, or even without concentrate supplementation. Production responses to increased levels of... more
The main objective was to evaluate the potential of grass silages of very high quality to support a high milk yield with a low or moderate, or even without concentrate supplementation. Production responses to increased levels of concentrate supplementation with 3 primary growth grass silages differing in digestibility were studied using 66 Norwegian Red dairy cows. Roundbale silage was produced from a timothy-dominated sward at very early (H1), early (H2), and normal (H3) stages of crop maturity. Crops were rapidly wilted (<24h) and a formic acid-based additive was applied. All silages were restrictedly fermented. Silage digestible organic matter in dry matter (DM) values were 747, 708, and 647 g/kg of DM for H1, H2, and H3, respectively. Dietary treatments were fed in a 3×3 factorial arrangement of the 3 silages supplemented with 3 concentrate levels (4, 8, and 12 kg/d) and, additionally, H1 was offered without concentrates and H3 with 16 kg/d, giving a total of 11 diets. Cows, ...
Research Interests: Dairy Science, Diet, Lactation, Animal Production, Female, and 8 moreAnimals, Poaceae, Eating, Milk, Cattle, Time Factors, Food Sciences, and Silage
The effect of 3 fermentation methods, in situ (IS) in 4 lactating cows (average pH of 5.8), in vitro (IVn) with media pH of 6.8, or in vitro (IVa) with media pH adjusted to 6.0 using citric acid, on fiber degradation parameters was... more
The effect of 3 fermentation methods, in situ (IS) in 4 lactating cows (average pH of 5.8), in vitro (IVn) with media pH of 6.8, or in vitro (IVa) with media pH adjusted to 6.0 using citric acid, on fiber degradation parameters was studied using feeds ground to different particle sizes. Corn silage (CS), grass silage (GS), barley grain (B), sugar beet pulp (BP), and rapeseed cake (RC) were ground using a shear mill. Silages were ground through 8-, 4-, 2-, or 1-mm screens, B and BP through 4-, 2-, or 1-mm screens, and RC through 2- or 1-mm screens. The amylase-treated NDF (aNDF) content of samples ground using a 1-mm screen was 399, 431, 197, 480, and 251 g/kg of DM for CS, GS, B, BP, and RC, respectively, but increased with increasing screen size. Materials were incubated for 0, 6, 12, 24, 48, and 96 h IS, IVn, or IVa. Inoculum for IVn and IVa was prepared as a composite from the cows used for IS. The potentially degradable aNDF (D(0)), indegradable aNDF (I), lag time (L), and fract...
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The objective of this digestibility assessment was to determine whether there are significant differences in the digestibility of Roundup Ready (glyphosate-tolerant) and conventional sugar beet, fodder beet, and beet pulp produced from... more
The objective of this digestibility assessment was to determine whether there are significant differences in the digestibility of Roundup Ready (glyphosate-tolerant) and conventional sugar beet, fodder beet, and beet pulp produced from sugar beet varieties when fed to sheep (seven wethers per treatment group). Three experiments were conducted in this assessment. Experiment 1 (35 wethers) compared one glyphosate-tolerant fodder beet variety with four conventional varieties, Exp. 2 (42 wethers) compared one glyphosate-tolerant sugar beet variety with five conventional varieties, and Exp. 3 (42 wethers) compared beet pulp derived from glyphosate-tolerant sugar beet with beet pulp from five European locations. The experimental phase consisted of a 2-wk preliminary period followed by a 1-wk collection period for Exp. 1 and 2, and a 1-wk preliminary period followed by a 1-wk digestibility collection period for Exp. 3. Diets were comprised of grass hay at 30, 30, and 20% of DM for Exp. 1, ...
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The effect of increased postruminal supply of lysine and methionine was investigated in a production trial involving 64 dairy cows in early lactation. Within each of two basal rations, based on either corn silage or grass silage, rations... more
The effect of increased postruminal supply of lysine and methionine was investigated in a production trial involving 64 dairy cows in early lactation. Within each of two basal rations, based on either corn silage or grass silage, rations were either naturally deficient in lysine or fortified with 24 g of lysine in a rumen-protected form and naturally deficient in methionine or fortified with 12 g of methionine in a rumen-protected form. The data were analyzed separately for the four lysine and the four methionine treatment groups. Milk production, body weight gain, and plasma concentrations of insulin-like growth factor-I, bovine somatotropin, insulin, glucose, nonesterified fatty acids, and urea were monitored over a 12-wk period. Supplementation with protected methionine led to increases in milk fat and protein contents of 2.4 and 1.8 g/kg of milk, respectively. Supplementation with protected lysine or methionine numerically increased protein yield comparable to values reported in...