Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

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    Enteric methane production, rumen volatile fatty acid concentrations, and milk fatty acid composition in lactating Holstein-Friesian cows fed grass silage - or corn silage-based diets
    Gastelen, S. van; Antunes Fernandes, E.C. ; Hettinga, K.A. ; Klop, G. ; Alferink, S.J.J. ; Hendriks, W.H. ; Dijkstra, J. - \ 2015
    Journal of Dairy Science 98 (2015)3. - ISSN 0022-0302 - p. 1915 - 1927.
    dairy-cows - maize silage - ruminal fermentation - feed-intake - n balance - cattle - emissions - supplementation - digestibility - performance
    The objective of this study was to determine the effects of replacing grass silage (GS) with corn silage (CS) in dairy cow diets on enteric methane (CH4) production, rumen volatile fatty acid (FA) concentrations, and milk FA composition. A completely randomized block design experiment was conducted with 32 multiparous lactating Holstein-Friesian cows. Four dietary treatments were used, all having a roughage-to-concentrate ratio of 80:20 based on dry matter (DM). The roughage consisted of either 100% GS, 67% GS and 33% CS, 33% GS and 67% CS, or 100% CS (all DM basis). Feed intake was restricted (95% of ad libitum DM intake) to avoid confounding effects of DM intake on CH4 production. Nutrient intake, apparent digestibility, milk production and composition, nitrogen (N) and energy balance, and CH4 production were measured during a 5-d period in climate respiration chambers after adaptation to the diet for 12 d. Increasing CS proportion linearly decreased neutral detergent fiber and crude protein intake and linearly increased starch intake. Milk production and milk fat content (on average 23.4 kg/d and 4.68%, respectively) were not affected by increasing CS inclusion, whereas milk protein content increased quadratically. Rumen variables were unaffected by increasing CS inclusion, except the molar proportion of butyrate, which increased linearly. Methane production (expressed as grams per day, grams per kilogram of fat- and protein-corrected milk, and as a percent of gross energy intake) decreased quadratically with increasing CS inclusion, and decreased linearly when expressed as grams of CH4 per kilogram of DM intake. In comparison with 100% GS, CH4 production was 11 and 8% reduced for the 100% CS diet when expressed per unit of DM intake and per unit fat- and protein-corrected milk, respectively. Nitrogen efficiency increased linearly with increased inclusion of CS. The concentration of trans C18:1 FA, C18:1 cis-12, and total CLA increased quadratically, and iso C16:0, C18:1 cis-13, and C18:2n-6 increased linearly, whereas the concentration of C15:0, iso C15:0, C17:0, and C18:3n-3 decreased linearly with increasing inclusion of CS. No differences were found in short- and medium-straight, even-chain FA concentrations, with the exception of C4:0 which increased linearly with increased inclusion of CS. Replacing GS with CS in a common forage-based diet for dairy cattle offers an effective strategy to decrease enteric CH4 production without negatively affecting dairy cow performance, although a critical level of starch in the diet seems to be needed.
    Effects of dietary starch content and rate of fermentation on methane production in lactating dairy cows
    Hatew, B. ; Podesta, S.C. ; Laar, H. van; Pellikaan, W.F. ; St-Pierre, J.L. ; Dijkstra, J. ; Bannink, A. - \ 2015
    Journal of Dairy Science 98 (2015)1. - ISSN 0022-0302 - p. 486 - 499.
    microbial protein-synthesis - high-moisture corn - cattle fed barley - milk-production - ruminal fermentation - feed-intake - rumen fermentation - enteric methane - n balance - beet pulp
    The objective of this study was to investigate the effects of starch varying in rate of fermentation and level of inclusion in the diet in exchange for fiber on methane (CH4) production of dairy cows. Forty Holstein-Friesian lactating dairy cows of which 16 were rumen cannulated were grouped in 10 blocks of 4 cows each. Cows received diets consisting of 60% grass silage and 40% concentrate (dry matter basis). Cows within block were randomly assigned to 1 of 4 different diets composed of concentrates that varied in rate of starch fermentation [slowly (S) vs. rapidly (R) rumen fermentable; native vs. gelatinized corn grain] and level of starch (low vs. high; 270 vs. 530 g/kg of concentrate dry matter). Results of rumen in situ incubations confirmed that the fractional rate of degradation of starch was higher for R than S starch. Effective rumen degradability of organic matter was higher for high than low starch and also higher for R than S starch. Increased level of starch, but not starch fermentability, decreased dry matter intake and daily CH4 production. Milk yield (mean 24.0 ± 1.02 kg/d), milk fat content (mean 5.05 ± 0.16%), and milk protein content (mean 3.64 ± 0.05%) did not differ between diets. Methane expressed per kilogram of fat- and protein-corrected milk, per kilogram of dry matter intake, or as a fraction of gross energy intake did not differ between diets. Methane expressed per kilogram of estimated rumen-fermentable organic matter (eRFOM) was higher for S than R starch–based diets (47.4 vs. 42.6 g/kg of eRFOM) and for low than high starch–based diets (46.9 vs. 43.1 g/kg of eRFOM). Apparent total-tract digestibility of neutral detergent fiber and crude protein were not affected by diets, but starch digestibility was higher for diets based on R starch (97.2%) compared with S starch (95.5%). Both total volatile fatty acid concentration (109.2 vs. 97.5 mM) and propionate proportion (16.5 vs. 15.8 mol/100 mol) were higher for R starch– compared with S starch–based diets but unaffected by the level of starch. Total N excretion in feces plus urine and N retained were unaffected by dietary treatments, and similarly energy intake and output of energy in milk expressed per unit of metabolic body weight were not affected by treatments. In conclusion, an increased rate of starch fermentation and increased level of starch in the diet of dairy cattle reduced CH4 produced per unit of eRFOM but did not affect CH4 production per unit of feed dry matter intake or per unit of milk produced.
    Estimation of residual energy intake and its genetic background during the growing period in pigs
    Shirali, M. ; Doeschl-Wilson, A. ; Duthie, C. ; Knap, P.W. ; Kanis, E. ; Arendonk, J.A.M. van; Roehe, R. - \ 2014
    Livestock Science 168 (2014). - ISSN 1871-1413 - p. 17 - 25.
    feed-intake - production traits - body-composition - nitrogen-excretion - chemical-analysis - yorkshire swine - growth - parameters - association - efficiency
    The aims of this study were to (i) compare models estimating residual energy intake (REI) using either lean and fat tissue growth or their proxy traits (average daily gain (ADG) and backfat thickness (BF)); (ii) determine genetic characteristics of REI at different growth stages and the entire test period; and (iii) examine 9 genetic and phenotypic relationships of REI with other production traits. Data from 315 pigs of an F2 generation were used which originated from crossing Pietrain sires with a commercial crossbred dam population. Average daily protein (APD) and lipid deposition (ALD), as measurements of lean and fat tissue growth, were obtained using the deuterium dilution technique on live animals. During growth from 60 to 140 kg, REI was estimated using 4 different models for energy intake that included, besides other systematic effects, (1) ADG and BF; (2) APD and ALD; (3) and (4) incorporated the same covariables as the first two models, respectively, but pre-adjusted for systematic effects. Genetic parameters and estimated breeding values were obtained based on univariate animal models using REML analysis. Over the entire growing period, heritabilities of different REI using different models were all estimated at 0.44 and their genetic correlations were at unity. At different growth stages heritabilities for REI were greater ranging from 0.47 to 0.50. Genetic correlations between REI estimates at different stages of growth, obtained using genetic model 4, indicated that REI at 60 to 90 kg was non-significantly (P>0.05) associated with REI at 90–120 kg (0.32±0.29) and 120–140 kg (0.28±0.28), but REI of the latter growth stages showed a significant (P
    Chemical composition and in vitro total gas and methane production of forage species from the Mid Rift Valley grasslands of Ethiopia
    Bezabih, M. ; Pellikaan, W.F. ; Tolera, A. ; Khan, N.A. ; Hendriks, W.H. - \ 2014
    Grass and Forage Science 69 (2014)4. - ISSN 0142-5242 - p. 635 - 643.
    feed-intake - production profiles - southern ethiopia - detergent fiber - ruminant feeds - zebu cattle - rumen fluid - fermentation - protein - degradability
    There is increasing interest in sustainable land use in the tropics to optimize animal production while also reducing methane (CH4) emissions, but information on nutritive value and CH4-emission potential of tropical forage species is limited. Samples of 24 grasses and five other forages were collected during the main rainy season on randomly positioned quadrats in semi-arid grassland in the Mid Rift Valley of Ethiopia. Samples were pooled by species, analysed for chemical composition and incubated with rumen fluid to determine total gas and CH4-emission potentials using a fully automated in vitro gas production apparatus. Organic matter digestibility (OMD) and metabolizable energy (ME) contents were calculated from chemical composition and gas production data. Large variability was observed among forages for all nutritional variables considered. The grasses Eleusine multiflora, Pennisetum stramineum, Dactyloctenium aegyptium, Eragrostis aspera, Cenchrus ciliaris and Eragrostis cilianensis showed relatively high OMD (68–72%) and ME values (9 1– 10 2 MJ kg 1 dry matter). Melinis repens, E. multiflora and the non-legume forb Zaleya pentandra showed relatively low CH4 to total gas ratios; these species may have potential for use in low CH4-emission forage diets. Acacia tortilis fruits had high content of crude protein and moderate ME values, and may be an ideal feed supplement for the grazing ruminant. Sodium content was below the recommended level for ruminants in all the forage species. Overall, the pasture stand during the main growing season was evaluated as having moderate nutritional quality.
    Nutritional status of cattle grazing natural pasture in the Mid Rift Valley grasslands of Ethiopia measured using plant cuticular hydrocarbons and their isotope enrichment
    Bezabih, M. ; Pellikaan, W.F. ; Tolera, A. ; Khan, N.A. ; Hendriks, W.H. - \ 2014
    Livestock Science 161 (2014). - ISSN 1871-1413 - p. 41 - 52.
    n-alkanes - diet selection - compensatory growth - southern ethiopia - mineral status - feed-intake - botanical composition - mammalian herbivores - tropical forages - detergent fiber
    The seasonal diet composition, digestibility and nutrient intake of cattle grazing on natural pasture in the Mid Rift valley region of Ethiopia were determined using an improved n-alkanes method. Sixteen local Borana and Arsi cattle (8 bulls and 8 heifers, 175±10 kg weight) were randomly selected from herds at two sites; a moderately grazed ranch and a heavily grazed, communal grassland area. Grazing behaviour was observed and herbage species consumed sampled during five periods (early-dry, dry, short-rainy, main-rainy and end-of-rainy seasons) throughout the year at the two grazing sites. During each period, animals were dosed twice daily with 152±4 mg of C32 and 150±3 mg C36 alkanes for 10 consecutive days, with faeces samples collected in the morning during the last five days to determine dry matter intake (DMI).The proportion of consumed herbage species in the diet was determined using n-alkanes and their carbon isotope enrichments as markers, while the energy and nutrient intakes were derived from the DMI, digestibility, and diet composition of the DM consumed. Marked seasonal variations (P
    Genetic correlations between lactation performance and growing-finishing traits in pigs
    Bergsma, R. ; Mathur, P.K. ; Kanis, E. ; Verstegen, M.W.A. ; Knol, E.F. ; Arendonk, J.A.M. van - \ 2013
    Journal of Animal Science 91 (2013)8. - ISSN 0021-8812 - p. 3601 - 3611.
    feed-intake - multilevel selection - body development - sows - parameters - growth - inheritance - components - efficiency - energy
    Genetic selection for increased litter size of sows increases the risk of a large negative energy balance during lactation. Furthermore, the feed intake capacity of the lactating sows might be reduced due to the simultaneous selection for greater feed efficiency during the growth phase when sows were actually reared as finishers but later on selected for breeding. There is a need to improve lactation performance of sows and continue selection for feed efficiency of grower-finishers in commercial breeding. Therefore, this study was conducted to estimate genetic correlations between growing-finishing traits and lactation performance traits. An additional objective was to study the impact of including additive social effects in the animal model on genetic correlation estimates. Analyses were performed on a population of 1,149 commercial crossbred sows with repeated observations on lactation performance traits and their 7,723 grower-finisher offspring. The genetic correlation between daily BW gain of grower-finishers and starting BW of lactating sows was positive (rg = 0.24; P <0.05). The correlation between off-test backfat of grower-finishers and fat mass of lactating sows was also positive (rg = 0.53; P <0.05). The genetic regulation of feed intake from the beginning of lactation seems to differ from the genetic regulation of feed intake during the growing-finishing period, as the correlation between these 2 traits was low (rg = +0.23; P <0.05). Feed efficiency during growing-finishing and lactation phases showed similar tendencies as the genetic correlation between residual feed intake of the grower-finisher and lactation efficiency of sows was –0.51 (P <0.05). Taking heritable social effects into account for daily BW gain and feed intake did not affect the genetic correlation estimates, either within growing-finishing traits or between growing-finishing traits and lactation performance traits. It was concluded that in the absence of antagonistic genetic correlations, selection for growing-finishing traits in dam lines could be combined with selection for lactation performance traits.
    Oxygen Consumption Constrains Food Intake in Fish Fed Diets Varying in Essential Amino Acid Composition
    Subramanian, S. ; Geurden, I. ; Figueiredo-Silva, A.C. ; Nusantoro, S. ; Kaushik, S.J. ; Verreth, J.A.J. ; Schrama, J.W. - \ 2013
    PLoS ONE 8 (2013)8. - ISSN 1932-6203 - 7 p.
    trout oncorhynchus-mykiss - european sea bass - rainbow-trout - dissolved-oxygen - nile tilapia - feed-intake - oreochromis-niloticus - salmo-gairdneri - self-selection - protein
    Compromisation of food intake when confronted with diets deficient in essential amino acids is a common response of fish and other animals, but the underlying physiological factors are poorly understood. We hypothesize that oxygen consumption of fish is a possible physiological factor constraining food intake. To verify, we assessed the food intake and oxygen consumption of rainbow trout fed to satiation with diets which differed in essential amino acid (methionine and lysine) compositions: a balanced vs. an imbalanced amino acid diet. Both diets were tested at two water oxygen levels: hypoxia vs. normoxia. Trout consumed 29% less food under hypoxia compared to normoxia (p0.05). This difference in food intake between diets under normoxia together with the identical oxygen consumption supports the hypothesis that food intake in fish can be constrained by a set-point value of oxygen consumption, as seen here on a six-week time scale.
    Piglet birth weight and litter uniformity: Effects of weaning-to-pregnancy interval and body condition changes in sows of different parities and crossbred lines
    Wientjes, J.G.M. ; Soede, N.M. ; Knol, E.F. ; Brand, H. van den; Kemp, B. - \ 2013
    Journal of Animal Science 91 (2013)5. - ISSN 0021-8812 - p. 2099 - 2107.
    subsequent reproductive-performance - nutritionally induced relationships - feed-intake - estrus interval - follicle development - luteinizing-hormone - conception interval - genetic-parameters - ovulation interval - oocyte maturation
    Piglet birth weight and litter uniformity were studied in sows of different parities and crossbred lines in relation to 1) the weaning-to-pregnancy interval (WPI); and 2) sow body condition changes (in BW and backfat thickness) during lactation and gestation in sows with a short WPI (= 7d). At the IPG research farm, individual piglet birth weights and sow body condition (BW and backfat thickness at farrowing and weaning) were measured of 949 TOPIGS20 and 889 TOPIGS40 sows with > 4 total born piglets, inseminated between 2003 and 2011. In all analyses, mean piglet birth weight and birth weight SD and CV were corrected for total number born. Total number born was higher in sows with a WPI of 8 to 21d (+ 1.2 piglets; n = 72) and >21d (+ 0.7 piglets; n = 182) compared with sows with a WPI = 7d (P <0.01; n = 1,584). Mean piglet birth weight was not affected by WPI. Birth weight SD (- 23 g) and CV (- 1.7%) were lower in sows with a WPI > 21d compared with sows with a WPI = 7d (P <0.01). Effects of WPI were independent of sow parity. Effects of body condition changes in sows with a WPI = 7d were studied separately in TOPIGS20 sows inseminated between 2006 and 2011 (n = 808) and in TOPIGS40 sows inseminated between 2003 and 2008 (n = 747). Sow body condition loss during lactation was not related with subsequent total number born or mean piglet birth weight. Only in TOPIGS20 sows, more BW loss during lactation was related with higher subsequent birth weight SD (ß = 0.83 g/kg, P <0.01; ß = 1.62 g/%, P <0.01), and more backfat loss during lactation was related with higher subsequent birth weight SD (ß = 5.11 g/mm, P <0.01) and CV (ß = 0.36 %/mm, P <0.01), independent of sow parity. Sow BW increase during gestation was negatively related with total number born (TOPIGS20: ß = - 0.06 and - 0.05 piglet/kg BW increase for parity 2 (P <0.01) and 3 and 4 ( P <0.01), respectively; TOPIGS40: ß = - 0.04 piglet/kg BW increase (P <0.01) independent of sow parity). Sow BW increase during gestation was positively related with birth weight SD (TOPIGS20: ß = 0.63 g/kg BW increase (P = 0.01) independent of sow parity). Sow body condition increase during gestation was not related with mean piglet birth weight. To conclude, this study shows that litter uniformity is compromised by severe sow body condition loss during lactation and improved in sows with a prolonged WPI. These effects are likely related with (insufficient) restoration of follicle development
    Nitrogen excretion at different stages of growth and its association with production traits in growing pigs
    Shirali, M. ; Doeschl-Wilson, A. ; Knap, P.W. ; Duthie, C. ; Kanis, E. ; Arendonk, J.A.M. van; Roehe, R. - \ 2012
    Journal of Animal Science 90 (2012)6. - ISSN 0021-8812 - p. 1756 - 1765.
    meat quality - carcass characteristics - body-composition - feed-intake - phosphorus consumption - chemical-analysis - halothane gene - performance - losses
    The objectives of this study were to determine nitrogen loss at different stages of growth and during the entire growing period and to investigate the associations between nitrogen excretion and production traits in growing pigs. Data from 315 pigs of an F-2 population which originated from crossing Pietrain sires with a commercial dam line were used. Nitrogen retention was derived from protein retention as measured using the deuterium dilution technique during different stages of growth (60 to 90 kg, 90 to 120 kg, and 120 to 140 kg). Pigs were fed ad libitum with 2 pelleted diets containing 17% (60 to 90 kg) and 16.5% (90 to 120 and 120 to 140 kg) CP. Average daily nitrogen excretion (ADNE) within each stage of growth was calculated on the basis of the accumulated difference between average daily nitrogen intake (ADNI) and average daily nitrogen retention (ADNR). Least ADNE, nitrogen excretion per BW gain (NEWG) and total nitrogen excretion (TNE) were observed during growth from 60 to 90 kg. In contrast, the greatest ADNE, NEWG, and TNE were found during growth from 120 to 140 kg. Statistical analyses indicated that gender, housing type, the ryanodine receptor 1 (RYR1) gene, and batch influenced nitrogen excretion (P <0.05), but the degree and direction of influences differed between growth stages. Gender differences showed that gilts excreted less nitrogen than barrows (P <0.05), which was associated with decreased feed conversion ratio (FCR; feed: gain) and lipid: protein gain ratio. Single-housed pigs showed reduced nitrogen excretion compared with group-housed pigs (P <0.05). In comparison to other genotypes, pigs carrying genotype NN (homozygous normal) at the RYR1 locus had the least nitrogen excretion (P <0.05) at all stages of growth except from 60 to 90 kg. The residual correlations indicated that NEWG and TNE have large positive correlations with FCR (r = 0.99 and 0.91, respectively) and moderate negative correlations with ADG (r = -0.53 and -0.48, respectively), for the entire growing period. Improvement in FCR, increase in ADG and reduction in lipid: protein gain ratio by 1 phenotypic SD reduced TNE per pig by 709 g, 307 g, and 211 g, respectively, over the entire growing period. The results indicate that nitrogen excretion changes substantially during growth, and it can be reduced most effectively by improvement of feed efficiency and to a lesser extent through the improvement of BW gain or body composition or both.
    Genetic and nongenetic variation in plasma and milk ß-hydroxybutyrate and milk acetone concentrations of early-lactation dairy cows
    Drift, S.G.A. van der; Hulzen, K.J.E. van; Teweldemedhn, T.G. ; Jorritsma, R. ; Nielen, M. ; Heuven, H.C.M. - \ 2012
    Journal of Dairy Science 95 (2012)11. - ISSN 0022-0302 - p. 6781 - 6787.
    holstein cows - subclinical ketosis - metabolic predictors - health disorders - energy-balance - body-weight - feed-intake - cattle - parameters - yield
    This study assessed genetic variation, heritability estimates, and genetic correlations for concentrations of plasma ß-hydroxybutyrate (BHBA), milk BHBA, and milk acetone in early lactation to investigate differences between cows in susceptibility to hyperketonemia and possibilities to use test-day milk ketone bodies for genetic improvement. Blood and test-day milk samples were collected on randomly selected dairy farms in the Netherlands from cows of various parities between 5 and 60 d in milk. Plasma samples were analyzed for BHBA (reference test for hyperketonemia) and test-day milk samples were analyzed for BHBA and acetone using Fourier-transform infrared spectroscopy. The final data set consisted of plasma BHBA concentrations of 1,615 cows from 122 herds. Milk BHBA and milk acetone concentrations were determined for 1,565 cows. Genetic variation, heritability, and proportion of phenotypic variation attributable to the herd were estimated using an animal model with fixed effects for parity and season, a covariate for days in milk, and random effects for herd, animal, and error. Genetic correlations for plasma BHBA, milk BHBA, and milk acetone were estimated using bivariate analyses. The heritability estimate for plasma BHBA concentrations in early lactation was 0.17, whereas heritability estimates for milk BHBA and milk acetone were 0.16 and 0.10, respectively. This indicates that selective breeding may contribute to a lower incidence of hyperketonemia in early lactation. For the 3 traits, the proportion of variance attributable to herd was larger than the additive genetic variance, underlining the importance of on-farm feeding and management in the etiology of hyperketonemia in fresh cows. Prevention strategies for hyperketonemia can, therefore, include both feeding and management strategies at dairy farms (short-term) and genetic improvement through breeding programs (long-term). Genetic correlations between concentrations of plasma BHBA and milk BHBA (0.52) or milk acetone (0.52) were moderate. As milk ketone bodies can be routinely analyzed at test days, this may provide a practical alternative for breeding programs aimed at reducing hyperketonemia in early lactation.
    Link between lipid metabolism and voluntary food intake in rainbow trout fed coconut oil rich in medium-chain TAG
    Figueiredo-Silva, A.C. ; Kaushik, S. ; Terrier, F. ; Schrama, J.W. ; Médale, F. ; Geurden, I. - \ 2012
    The British journal of nutrition 107 (2012)11. - ISSN 0007-1145 - p. 1714 - 1725.
    fatty-acid-composition - drum sciaenops-ocellatus - salmon salmo-salar - polka-dot grouper - oncorhynchus-mykiss - feed-intake - plasma cholecystokinin - cromileptes-altivelis - tissue distribution - energy-intake
    We examined the long-term effect of feeding coconut oil (CO; rich in lauric acid, C12) on voluntary food intake and nutrient utilisation in rainbow trout (Oncorhynchus mykiss), with particular attention to the metabolic use (storage or oxidation) of ingested medium-chain TAG. Trout were fed for 15 weeks one of the four isoproteic diets containing fish oil (FO) or CO as fat source (FS), incorporated at 5 % (low fat, LF) or 15 % (high fat, HF). Fat level or FS did not modify food intake (g/kg0·8 per d), despite higher intestinal cholecystokinin-T mRNA in trout fed the HF-FO diet. The HF diets relative to the LF ones induced higher growth and adiposity, whereas the replacements of FO by CO resulted in similar growth and adiposity. This, together with the substantial retention of C12 (57 % of intake), suggests the relatively low oxidation of ingested C12. The down-regulation of carnitine palmitoyl-transferase-1 (CPT-1) confirms the minor dependency of medium-chain fatty acids (MCFA) on CPT-1 to enter the mitochondria. However, MCFA did not up-regulate mitochondrial oxidation evaluated using hepatic hydroxyacyl-CoA dehydrogenase as a marker, in line with their high retention in body lipids. At a low lipid level, MCFA increased mRNA levels of fatty acid synthase, elongase and stearoyl-CoA desaturase in liver, showing the hepatic activation of fatty acid synthesis pathways by MCFA, reflected by increased 16 : 0, 18 : 0, 16 : 1, 18 : 1 body levels. The high capacity of trout to incorporate and transform C12, rather than to readily oxidise C12, contrasts with data in mammals and may explain the absence of a satiating effect of CO in rainbow trout.
    Merging and characterising phenotypic data on conventional and rare traits from dairy cattle experimental resources in three countries
    Banos, G. ; Coffey, M.P. ; Veerkamp, R.F. ; Berry, D.P. ; Wall, E. - \ 2012
    Animal 6 (2012)7. - ISSN 1751-7311 - p. 1040 - 1048.
    body condition score - daily energy-balance - dry-matter intake - milk-production - genetic merit - feed-intake - random regression - grass intake - cows - yield
    This study set out to demonstrate the feasibility of merging data from different experimental resource dairy populations for joint genetic analyses. Data from four experimental herds located in three different countries (Scotland, Ireland and the Netherlands) were used for this purpose. Animals were first lactation Holstein cows that participated in ongoing or previously completed selection and feeding experiments. Data included a total of 60 058 weekly records from 1630 cows across the four herds; number of cows per herd ranged from 90 to 563. Weekly records were extracted from the individual herd databases and included seven traits: milk, fat and protein yield, milk somatic cell count, liveweight, dry matter intake and energy intake. Missing records were predicted with the use of random regression models, so that at the end there were 44 weekly records, corresponding to the typical 305-day lactation, for each cow. A total of 23 different lactation traits were derived from these records: total milk, fat and protein yield, average fat and protein percentage, average fat-to-protein ratio, total dry matter and energy intake and average dry matter intake-to-milk yield ratio in lactation weeks 1 to 44 and 1 to 15; average milk somatic cell count in lactation weeks 1 to 15 and 16 to 44; average liveweight in lactation weeks 1 to 44; and average energy balance in lactation weeks 1 to 44 and 1 to 15. Data were subsequently merged across the four herds into a single dataset, which was analysed with mixed linear models. Genetic variance and heritability estimates were greater (P <0.05) than zero for all traits except for average milk somatic cell count in weeks 16 to 44. Proportion of total phenotypic variance due to genotype-by-environment (sire-by-herd) interaction was not different (P > 0.05) from zero. When estimable, the genetic correlation between herds ranged from 0.85 to 0.99. Results suggested that merging experimental herd data into a single dataset is both feasible and sensible, despite potential differences in management and recording of the animals in the four herds. Merging experimental data will increase power of detection in a genetic analysis and augment the potential reference population in genome-wide association studies, especially of difficult-to-record traits
    Lactation Weight Loss in Primiparous Sows: Consequences for Embryo Survival and Progesterone and Relations with Metabolic Profiles
    Hoving, L.L. ; Soede, N.M. ; Feitsma, H. ; Kemp, B. - \ 2012
    Reproduction in Domestic Animals 47 (2012)6. - ISSN 0936-6768 - p. 1009 - 1016.
    growth-factor-i - dietary energy-source - feed-intake - reproductive-performance - hormone profiles - insulin - state - mobilization - restriction - pattern
    Our objective was to study reproductive consequences of lactation bodyweight loss occurring in primiparous sows with mild feed restriction and to relate these lactation weight losses and its consequences to metabolic profiles during lactation and subsequent early gestation. After weaning, 47 first-litter sows were retrospectively assigned to a high– (HWL, >13.8%, n = 24) or low (LWL, =13.8%, n = 23)–weight loss group. Thirty-six animals received an indwelling jugular vein catheter to determine lactational and gestational profiles of insulin-like growth factor-1 (IGF-1), non-esterified fatty acids (NEFA) and urea and gestational profiles of progesterone. At day 35 after insemination, sows were euthanized and their reproductive tract collected. Pregnancy rate was 75% (18/24) for HWL and 96% (22/23) for LWL sows. High–weight loss sows had a lower number of implantation sites (17.2 ± 0.8 vs 19.5 ± 0.7, respectively, p = 0.03) and a lower embryonic survival (65.6 ± 3.4 vs 77.4 ± 2.9%, p = 0.02), resulting in fewer vital embryos (14.9 ± 0.9 vs 16.8 ± 0.7, p = 0.07) than LWL sows. Progesterone peak values were reached later in HWL than in LWL sows (day 13.4 ± 0.5 vs 12.0 ± 0.5, respectively, p = 0.05). Gestational concentrations of IGF-1, NEFA and urea were almost identical for HWL and LWL sows, whilst numerical differences were seen during lactation. The current study shows negative consequences of lactational weight loss in mildly feed-restricted primiparous sows for embryonic survival and shows that these consequences seem only mildly related with metabolic alterations during lactation and not with metabolic alterations during subsequent gestation.
    Nutritionally Induced Relationships Between Insulin Levels During the Weaning-to-Ovulation Interval and Reproductive Characteristics in Multiparous Sows: II. Luteal Development, Progesterone and Conceptus Development and Uniformity
    Wientjes, J.G.M. ; Soede, N.M. ; Brand, H. van den; Kemp, B. - \ 2012
    Reproduction in Domestic Animals 47 (2012)1. - ISSN 0936-6768 - p. 62 - 68.
    uterine protein secretion - dietary energy-source - piglet birth-weight - primiparous sows - embryo survival - feed-intake - luteinizing-hormone - gilts - size - growth
    Insulin-stimulating sow diets before mating improve piglet uniformity. We studied effects of nutritionally induced differences in insulin levels during the weaning-to-ovulation interval (WOI) on luteal development, progesterone secretion and pre-implantation conceptus development and uniformity (d10). To create insulin contrasts, 32 multiparous sows were fed either a dextrose plus lactose containing diet (each 150 g/day) at 4 h intervals (DL treatment) or an isocalorically control diet (containing soybean oil) at 12 h intervals (CTRL treatment) during the WOI. After ovulation, all sows received a standard gestation diet at 12 h intervals. Ovulation rate, plasma progesterone levels, pregnancy rate and embryo survival did not differ between treatments. CTRL sows had a higher total luteal weight (11.2 vs 9.7 g; p = 0.03) than DL sows. Conceptus diameter at d10 of pregnancy tended to be larger in CTRL sows (diameter: 7.1 vs 6.4 mm; p = 0.07). Conceptus uniformity was not influenced by treatment. Insulin area under the curve (AUC) and mean insulin during the WOI were positively related with mean progesterone (ß values were 0.78 (ng/ml)/1000 µU and 0.14 (ng/ml)/(µU/ml) for AUC and mean, respectively; p <0.05) and maximal progesterone (ß values were 1.46 (ng/ml)/1000 µU and 0.27 (ng/ml)/(µU/ml) for AUC and mean, respectively; p <0.05) levels during the first 10 days of pregnancy, but not with conceptus development and uniformity. In conclusion, high insulin levels during the WOI seem to be beneficial for progesterone secretion in sows, probably mediated through beneficial effects of insulin on follicle development.
    Nutritionally Induced Relationships Between Insulin Levels During the Weaning-to-Ovulation Interval and Reproductive Characteristics in Multiparous Sows: I. Luteinizing Hormone, Follicle Development, Oestrus and Ovulation
    Wientjes, J.G.M. ; Soede, N.M. ; Brand, H. van den; Kemp, B. - \ 2012
    Reproduction in Domestic Animals 47 (2012)1. - ISSN 0936-6768 - p. 53 - 61.
    dietary energy-source - growth-factor-i - primiparous sows - feed-intake - lactation - glucose - gilts - pigs - performance - secretion
    To get more insight in how insulin secretion patterns and corresponding insulin-like growth factor-1 (IGF-1) levels are related to luteinizing hormone (LH) secretion, follicle development and ovulation, 32 multiparous sows were fed either a dextrose plus lactose-containing diet at 4 h intervals (DL; each 150 g/day) or an isocaloric control diet at 12 h intervals (CTRL; containing soybean oil) during the weaning-to-ovulation interval (WOI). Insulin parameters (basal, peak levels and mean insulin) and IGF-1 levels during the WOI were similar for both treatments, but the insulin secretion pattern differed (related with feeding frequency and meal sizes). Oestrus and ovulation characteristics were not influenced by treatment. The LH surge was higher in CTRL compared with DL sows (3.73 vs 3.00 ng/ml; p = 0.03). Average diameter (6.5 vs 6.1 mm; p = 0.08) and uniformity (CV: 11 vs 15%, p = 0.02) of follicles =3 mm at day 4 after weaning was higher in CTRL compared with DL sows. Basal insulin levels were positively related with follicle diameter at ovulation (ß = 0.05 mm/(µU/ml); p = 0.04) and negatively related with LH surge level (ß = -0.07 (ng/ml)/(µU/ml); p = 0.01). Insulin area under the curve (AUC) (ß = 0.037 (ng/ml)/1000 µU; p = 0.02) and IGF-1 levels (ß = 0.002 (ng/ml)/(ng/ml); p <0.01) were positively related to basal LH level around the LH surge. From these data, we conclude that insulin and IGF-1 levels during the WOI are related to LH secretion and follicle development. Not only the absolute level of insulin seems important, but also the pattern within a day in which insulin is secreted seems to affect LH secretion and development of pre-ovulatory follicles.
    Effects of forage type, forage to concentrate ratio, and crushed linseed supplementation on milk fatty acid profile in lactating dairy cows
    Sterk, A.R. ; Johansson, B.E.O. ; Taweel, H.Z.H. ; Murphy, M. ; Vuuren, A.M. van; Hendriks, W.H. ; Dijkstra, J. - \ 2011
    Journal of Dairy Science 94 (2011)12. - ISSN 0022-0302 - p. 6078 - 6091.
    conjugated linoleic acids - sunflower oil - feed-intake - fish-oil - diet - biohydrogenation - rumen - silage - responses - trans-10
    The effects of an increasing proportion of crushed linseed (CL) in combination with varying forage type (grass or corn silage) and forage to concentrate ratio (F:C), and their interactions on milk fatty acid (FA) profile of high-producing dairy cows was studied using a 3-factor Box-Behnken design. Sixteen Holstein and 20 Swedish Red cows were blocked according to breed, parity, and milk yield, and randomly assigned to 4 groups. Groups were fed different treatment diets formulated from combinations of the 3 main factors each containing 3 levels. Forage type (fraction of total forage dry matter, DM) included 20, 50, and 80% grass silage, with the remainder being corn silage. The F:C (DM basis) were 35:65, 50:50, and 65:35, and CL was supplied at 1, 3, and 5% of diet DM. Starch and neutral detergent fiber content (DM basis) of the treatment diets ranged from 117 to 209 g/kg and 311 to 388 g/kg, respectively. Thirteen treatment diets were formulated according to the Box-Behnken design. During 4 experimental periods of 21 d each, all treatment diets were fed, including a repetition of the center point treatment (50% grass silage, 50:50 F:C, 3% CL) during every period. Intake, production performance, and milk FA profile were measured, and response surface equations were derived for these variables. Shifting from 80% grass silage to 80% corn silage in the diet linearly increased dry matter intake (DMI), net energy for lactation (NEL) intake, cis-9,cis-12-C18:2 (C18:2n-6) intake, and milk yield, and linearly decreased cis-9,cis-12,cis-15-C18:3 (C18:3n-3) intake and milk fat content. Shifting from a high forage to a high concentrate diet linearly increased DMI, NEL intake, C18:2n-6 intake, and milk yield, and decreased milk fat content. Supplementation of CL linearly increased C18:3n-3 intake, but had no effect on DMI, NEL intake, milk yield, or milk fat content. Shifting from 80% grass silage to 80% corn silage linearly increased proportions of trans-10-C18:1 and C18:2n-6 in milk fat, whereas the proportions of trans-11,cis-15-C18:2 and C18:3n-3 linearly decreased. Significant interactions between CL supplementation and F:C were found for proportions of trans-10-C18:1, trans-15-C18:1, cis-15-C18:1, trans-11,cis-15-C18:2, and C18:3n-3 in milk fat, with the highest levels achieved when the diet contained 5% CL and a 35:65 F:C ratio. The effect of supplementing CL on several milk FA proportions, including C18:2n-6 and C18:3n-3, depends significantly on the F:C ratio and forage type in the basal diet.
    Lactulose as a marker of intestinal barrier function in pigs after weaning
    Wijtten, P.J.A. ; Verstijnen, J.J. ; Kempen, T.A.T.G. van; Perdok, H.B. ; Gort, G. ; Verstegen, M.W.A. - \ 2011
    Journal of Animal Science 89 (2011)5. - ISSN 0021-8812 - p. 1347 - 1357.
    bacterial translocation - villous height - weaned piglets - crypt depth - feed-intake - in-vitro - gut - permeability - dysfunction - malabsorption
    Intestinal barrier function in pigs after weaning is almost exclusively determined in terminal experiments with Ussing chambers. Alternatively, the recovery in urine of orally administered lactulose can be used to assess intestinal permeability in living animals. This experiment was designed to study the barrier function of the small intestine of pigs over time after weaning. The aim was to relate paracellular barrier function (measured by lactulose recovery in the urine) with macromolecular transport [measured by horseradish peroxidase (HRP) using Ussing chambers] and bacterial translocation to assess whether lactulose recovery is related to possible causes of infection and disease. Forty gonadectomized male pigs (6.7 ± 0.6 kg) were weaned (d 0) at a mean age of 19 d, fitted with urine collection bags, and individually housed. Pigs were dosed by oral gavage with a marker solution containing lactulose (disaccharide) and the monosaccharides l-rhamnose, 3-O-methylglucose, and d-xylose at 2 h and at 4, 8, and 12 d after weaning. The recovery of sugars in the urine was determined over 18 h after each oral gavage. The day after each permeability test, the intestines of 10 pigs were dissected to determine bacterial translocation to the mesenteric lymph nodes and jejunal permeability for HRP in Ussing chambers. Recovery of l-rhamnose in urine was affected by feed intake and by the time after weaning (P = 0.05). Recovery of lactulose from the urine was greater (P = 0.05) at 4, 8, and 12 d after weaning compared with the first day after weaning and was negatively correlated with feed intake (r = -0.63, P = 0.001). The mean translocation of aerobic bacteria to the mesenteric lymph nodes was greater at 5 and 13 d after weaning compared with d 1 (P = 0.05). Lactulose recovery showed no correlation with permeability for HRP nor with bacterial translocation (P > 0.05). Although both lactulose recovery and bacterial translocation increased over time after weaning, lactulose recovery did not correlate with the permeability for HRP nor bacterial translocation within a pig (P > 0.05). Therefore, we conclude that lactulose recovery in the urine of pigs after weaning is not associated with risk factors for infections. However, it appears to be possible to measure paracellular barrier function with orally administered lactulose in pigs shortly after weaning. Further studies will reveal whether this variable is relevant for the long-term performance or health of pigs after weaning
    Tensile fracture properties of seven tropical grasses at different phenological stages
    Jacobs, A.A.A. ; Scheper, J.A. ; Benvenutti, M.A. ; Gordon, I.J. ; Poppi, D.P. ; Elgersma, A. - \ 2011
    Grass and Forage Science 66 (2011)4. - ISSN 0142-5242 - p. 551 - 559.
    particle breakdown - foraging behavior - pasture grasses - residual stems - feed-intake - cattle - strength - ruminants - sward - resistance
    The intake of forage grasses by grazing ruminants is closely related to the mechanical fracture properties of grasses. The relationship between the tensile fracture properties of grasses and foraging behaviour is of particular importance in tropical reproductive swards composed of both stems and leaves. This study (i) quantified and compared the tensile fracture properties of stems and leaves of seven tropical grass species and (ii) provided insight into the underlying plant traits that explain differences in fracture properties between species. Fracture force, tensile strength, fracture energy and toughness of stems (in various phenological stages) and leaves were measured and compared among five introduced tropical grasses (Cenchrus ciliaris, Chloris gayana, Digitaria milanjiana, Megathyrsus maximus (syn. Panicum maximum), Setaria sphacelata) and two native tropical grasses (Setaria surgens and Dichanthium sericeum). Species differed significantly in fracture force and fracture energy, with stems and leaves of C. ciliaris and S. surgens requiring less force and energy to fracture and stems and leaves of M. maximus and S. sphacelata requiring more force and energy to fracture in comparison with the other species. Differences in tensile strength and toughness were less pronounced. The differences among species in fracture force and energy mainly resulted from differences in cross-sectional area of plant parts rather than from differences in tensile strength and toughness.
    Intestinal barrier function and absorption in pigs after waeaning: a review
    Wijtten, P.J.A. ; Meulen, J. van der; Verstegen, M.W.A. - \ 2011
    The British journal of nutrition 105 (2011)7. - ISSN 0007-1145 - p. 967 - 981.
    epithelium in-vitro - feed-intake - parenteral-nutrition - glucose-absorption - villous height - ion-transport - crypt depth - fatty-acids - weaned pig - piglets
    Under commercial conditions, weaning of piglets is associated with social, environmental and dietary stress. Consequently, small-intestinal barrier and absorptive functions deteriorate within a short time after weaning. Most studies that have assessed small-intestinal permeability in pigs after weaning used either Ussing chambers or orally administered marker probes. Paracellular barrier function and active absorption decrease when pigs are weaned at 3 weeks of age or earlier. However, when weaned at 4 weeks of age or later, the barrier function is less affected, and active absorption is not affected or is increased. Weaning stress is a critical factor in relation to the compromised paracellular barrier function after weaning. Adequate feed intake levels after weaning prevent the loss of the intestinal barrier function. Transcellular transport of macromolecules and passive transcellular absorption decrease after weaning. This may reflect a natural intestinal maturation process that is enhanced by the weaning process and prevents the pig from an antigen overload. It seems that passive and active absorption after weaning adapt accurately to the new environment when pigs are weaned after 3 weeks of age. However, when weaned at 3 weeks of age or earlier, the decrease in active absorption indicates that pigs are unable to sufficiently adapt to the new environment. To improve weaning strategies, future studies should distinguish whether the effect of feed intake on barrier function can be directed to a lack of a specific nutrient, i.e. energy or protein.
    Effects of altrenogest treatments before and after weaning on follicular development, farrowing rate, and litter size in sows
    Leeuwen, J.J.J. van; Martens, M.R.T.M. ; Jourquin, J. ; Draincourt, M.A. ; Kemp, B. ; Soede, N.M. - \ 2011
    Journal of Animal Science 89 (2011)8. - ISSN 0021-8812 - p. 2397 - 2406.
    primiparous sows - progestagen treatment - estrous-cycle - feed-intake - gilts - fertility - regumate - piglet - estrus - synchronization
    In a previous study, we showed that follicle size at weaning affects a sow’s response to a short altrenogest treatment after weaning. In this study, an attempt was made to prevent growth of follicles into larger size categories before weaning using different altrenogest treatments before weaning to improve reproductive performance after postweaning altrenogest treatments. Sows (87 primiparous and 130 multiparous) were assigned to: control (no altrenogest treatment; n = 59), RU0-20 (20 mg altrenogest, d -1 to d 6; weaning = d 0; n = 53), RU40-20 (40 mg altrenogest, d -3 to d 0 and 20 mg altrenogest d 1 to d 6; n = 53), and RU20-20 (20 mg altrenogest, d -3 to d 6; n = 52). Follicle size was assessed daily with trans-abdominal ultrasound. Follicle size on d -3 (3.6 ± 0.7 mm) and at weaning (4.0 ± 0.7 mm) was similar for all treatments. Altrenogest-treated sows had larger follicles at the start of the follicular phase than control sows (5.4 ± 0.1 and 3.8 ± 0.2 mm, LS Means, respectively; P <0.0001) and on d 4 of the follicular phase (8.0 ± 0.1 and 6.7 ± 0.2 mm, LS Means, respectively; P <0.0001). Multiparous sows had larger follicles than primiparous sows at the start of the follicular phase (5.3 ± 0.1 and 4.7 ± 0.1 mm, LS Means, respectively; P <0.01) and on d 4 of the follicular phase (8.0 ± 0.1 and 7.0 ± 0.1 mm, LS Means, respectively; P <0.0001). Farrowing rate and litter size (born alive + dead) were not affected by treatment or parity. However, in primiparous sows, when mummies were included in litter size, altrenogest sows had larger litters than control sows (13.4 ± 0.5 and 11.9 ± 0.7 piglets, respectively; P = 0.02). In primiparous control sows, backfat depth at weaning and litter size were positively related (slope of the regression line = 0.82; P <0.05), which was not the case in primiparous altrenogest sows. In conclusion, the different altrenogest treatments before weaning did not prevent growth of follicles before weaning and similarly affected subsequent follicle development and fertility. In primiparous sows, altrenogest treatment after weaning increased the number of fetuses during pregnancy but positive effects seemed limited by uterine capacity. Altrenogest treatment after weaning improved litter size in primiparous sows with low backfat depth at weaning, which suggests a specific positive effect of a recovery period after weaning in sows with low body condition scores at weaning
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