47 research outputs found

    External validation of the GrazeIn model of pasture dry matter intake and milk yield prediction for cows managed at different calving dates and stocking rates

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    The aim was to evaluate the prediction accuracy of pasture dry matter intake (PDMI) and milk yield (MY) predicted by the GrazeIn model using a database representing 124 PDMI measurements at paddock level and 2232 MY measurements at cow level. External validation of the model was conducted using data collected from a trial carried out with Holstein-Friesian cows (n=72) while grazed 28 paddocks and were managed in a 2×2 factorial design by considering two calving dates (CD), with different number of days in milk (DIM), early (E, 29 DIM) vs. middle (M, 167 DIM), and two stocking rates (SR), medium (M, 3.9 cows ha-1) vs. high (H, 4.8 cows ha-1), under a rotational grazing system. Cows were randomly assigned to four grazing scenarios (EM, EH, MM and MH). The mean observed PDMI of the total database was 14.2 kg DM cow-1 day-1 while GrazeIn predicted a mean PDMI for the database of 13.8 kg DM cow-1 day-1. The mean bias was −0.4 kg DM cow-1 day-1. GrazeIn predicted PDMI for the total database with a relative prediction error (RPE) of 10.0% at paddock level. The mean observed MY of the database was 23.2 kg cow-1 day-1 while GrazeIn predicted a MY for the database of 23.1 kg cow-1 day-1. The mean bias was –0.1 kg cow-1 day-1. GrazeIn predicted MY for the total database with a mean RPE of 17.3% at cow level. For the scenarios investigated, GrazeIn predicted PDMI and MY with a low level of error which made it a suitable tool for decision support systems

    Utjecaj prinosa pašnjaka i pašnog obroka na kvalitetu travnjaka, unos paše i proizvodnju mlijeka.

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    Sixty-four Holstein-Friesian cows were randomly assigned to one of four treatments (M15, M20, H15 and H20) in a 2x2 factorial design, by considering: two pre-grazing pasture mass levels (PM, kg DM/ha): medium (M-1,600) vs. high (H-2,400); and two pasture allowance levels (PA, kg DM/cow/day): low (15) vs. high (20). Two periods (PI vs. PII) were studied. Sward density and pre-grazing sward height were higher in high compared to medium pre-grazing PM swards in PI (P<0.001, 255 vs. 235 kg DM/cm/ha and P<0.001, 14.8 vs. 10.9 cm, respectively) and PII (P<0.001, 216 vs. 196 kg DM/cm/ha and P<0.001, 14.3 vs. 13.0 cm, respectively). Lower post-grazing sward height and higher pasture utilization were obtained in low compared to high PA swards in PI (P<0.001, 4.1 vs. 4.9 cm and P<0.001, 98.8 vs. 89.9 %, respectively) and PII (P<0.001, 4.3 vs. 5.0 cm and P<0.001, 97.1 vs. 89.9 %, respectively). Pasture crude protein content and pasture organic matter digestibility were higher in medium compared to high pre-grazing PM swards in PI (P<0.001, 210 vs. 176 g/kg DM and P<0.05, 846 vs. 836 g/kg DM, respectively) and PII (P<0.05, 212 vs. 192 g/kg DM and P<0.05, 828 vs. 821 g/kg DM, respectively). This was due to higher leaf and lower dead proportions in medium than in high pre-grazing PM swards. Pasture dry matter intake (PDMI) (P<0.001, 16.5 vs. 14.7 kg DM/cow/day), milk yield (MY) (P<0.01, 23.8 vs. 22.7 kg/day) and milk solids yield (MSY) (P<0.05, 1.69 vs. 1.61 kg/cow) were higher in high compared to low PA swards in PI. Higher PDMI (P<0.001, 15.7 vs. 14.1 kg DM/cow/day), MY (P<0.001, 15.4 vs. 13.6 kg/day) and MSY (P<0.01, 1.19 vs. 1.08 kg/cow) were also found in high than in low PA swards in PII. The highest (P<0.001) milk output per ha (16,983 kg/ha) and milk solids per ha (1,268 kg/ha) were found in the group of dairy cows grazing in the M20 swards.Šezdeset četiri holštaj-frizijske krave nasumično su razvrstane u četiri skupine (M15, M20, H15 i H20), uzevši u obzir 2x2 faktorijalni dizajn s obzirom na: dvije razine prinosa pašnjaka prije napasivanja (PM, kg DM/ha) - srednja (M-1600) naprema visoka (H-2400), te dvije razine pašnog obroka (PA, kg DM / krava /dan) - niski (15) naprema visoki (20). Istražena su dva razdoblja (PI naprema PII). Između travnjaka s visokim i srednjim prinosom prije napasivanja (PM), u prvom razdoblju utvrđene su razlike s obzirom na gustoću travnjaka (P<0,001; H = 255 naprema M = 235 kg DM/cm/ha) i visinu trave (P<0,001; H = 14,8 naprema M = 10,9 cm). U drugom razdoblju, statistička značajnost i razlike između navedenih skupina iznosili su P<0,001; H = 216 naprema M = 196 kg DM/cm/ha i P<0,001; H = 14,3 naprema M = 13,0 cm. Najniža visina trave i najviša iskoristivost pašnjaka nakon napasivanja utvrđene su usporedbom niskog i visokog pašnog obroka tijekom prvog razdoblja (P<0,001; niski = 4,1 naprema visoki = 4,9 cm te P<0,001; niski = 98,8 naprema visoki = 89,9%) kao i tijekom drugog razdoblja (P<0,001; niski = 4,3 naprema visoki = 5,0 cm te P<0,001; niski = 97,1 naprema visoki = 89,9%). Sadržaj sirovih proteina i probavljivost organske tvari tijekom prvog razdoblja bili su viši kod pašnjaka sa srednjim prinosom pašnjaka prije napasivanja u odnosu na pašnjake s visokom razinom prinosa prije napasivanja (P<0,001; M = 210 naprema H = 176 g/kg DM i P<0,05; M = 846 naprema H = 836 g/kg DM. Tijekom drugog razdoblja, statistička značajnost i vrijednosti navedenih pokazatelja iznosili su (P<0,05; M = 212 naprema H = 192 g/kg DM i P<0,05; M = 828 naprema H = 821 g/kg DM). Navedeno se može pripisati većem udjelu lišća i manjem udjelu uvenule mase na pašnjacima sa srednjim prinosom prije napasivanja u odnosu na pašnjake s visokim prinosom prije napasivanja. Usporedba niskog i visokog pašnog obroka tijekom prvog razdoblja, pokazala je statistički značajne razlike za unos suhe tvari pašom (P<0,001; niski = 16,5 naprema visoki = 14,7 kg DM/krava/dnevno), proizvodnju mlijeka (P<0,01; niski = 23,8 naprema. visoki = 22,7 kg/day) te proizvodnju krute tvari mlijeka (P<0,05; niski = 1,69 naprema. visoki = 1,61 kg/krava). Tijekom drugog razdoblja, viši unos suhe tvari pašom utvrđen kod visokoga pašnog obroka u odnosu na niski pašni obrok (P<0,001; visoki = 15,7 naprema niski = 14,1 kg DM/krava/dnevno), viša je bila i proizvodnja mlijeka (P<0,001; visoki = 15,4 naprema niski = 13,6 kg/day) te proizvodnja krute tvari mlijeka (P<0,01; visoki = 1,19 naprema niski = 1,08 kg/krava). Najviša proizvodnja mlijeka po hektaru (P<0,001; 16,983 kg/ha) i krute tvari mlijeka po hektaru (1,268 kg/ha) utvrđena je kod krava koje su napasivane u skupini M20 travnjaka

    Utjecaj prinosa pašnjaka i pašnog obroka na kvalitetu travnjaka, unos paše i proizvodnju mlijeka.

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    Sixty-four Holstein-Friesian cows were randomly assigned to one of four treatments (M15, M20, H15 and H20) in a 2x2 factorial design, by considering: two pre-grazing pasture mass levels (PM, kg DM/ha): medium (M-1,600) vs. high (H-2,400); and two pasture allowance levels (PA, kg DM/cow/day): low (15) vs. high (20). Two periods (PI vs. PII) were studied. Sward density and pre-grazing sward height were higher in high compared to medium pre-grazing PM swards in PI (P<0.001, 255 vs. 235 kg DM/cm/ha and P<0.001, 14.8 vs. 10.9 cm, respectively) and PII (P<0.001, 216 vs. 196 kg DM/cm/ha and P<0.001, 14.3 vs. 13.0 cm, respectively). Lower post-grazing sward height and higher pasture utilization were obtained in low compared to high PA swards in PI (P<0.001, 4.1 vs. 4.9 cm and P<0.001, 98.8 vs. 89.9 %, respectively) and PII (P<0.001, 4.3 vs. 5.0 cm and P<0.001, 97.1 vs. 89.9 %, respectively). Pasture crude protein content and pasture organic matter digestibility were higher in medium compared to high pre-grazing PM swards in PI (P<0.001, 210 vs. 176 g/kg DM and P<0.05, 846 vs. 836 g/kg DM, respectively) and PII (P<0.05, 212 vs. 192 g/kg DM and P<0.05, 828 vs. 821 g/kg DM, respectively). This was due to higher leaf and lower dead proportions in medium than in high pre-grazing PM swards. Pasture dry matter intake (PDMI) (P<0.001, 16.5 vs. 14.7 kg DM/cow/day), milk yield (MY) (P<0.01, 23.8 vs. 22.7 kg/day) and milk solids yield (MSY) (P<0.05, 1.69 vs. 1.61 kg/cow) were higher in high compared to low PA swards in PI. Higher PDMI (P<0.001, 15.7 vs. 14.1 kg DM/cow/day), MY (P<0.001, 15.4 vs. 13.6 kg/day) and MSY (P<0.01, 1.19 vs. 1.08 kg/cow) were also found in high than in low PA swards in PII. The highest (P<0.001) milk output per ha (16,983 kg/ha) and milk solids per ha (1,268 kg/ha) were found in the group of dairy cows grazing in the M20 swards.Šezdeset četiri holštaj-frizijske krave nasumično su razvrstane u četiri skupine (M15, M20, H15 i H20), uzevši u obzir 2x2 faktorijalni dizajn s obzirom na: dvije razine prinosa pašnjaka prije napasivanja (PM, kg DM/ha) - srednja (M-1600) naprema visoka (H-2400), te dvije razine pašnog obroka (PA, kg DM / krava /dan) - niski (15) naprema visoki (20). Istražena su dva razdoblja (PI naprema PII). Između travnjaka s visokim i srednjim prinosom prije napasivanja (PM), u prvom razdoblju utvrđene su razlike s obzirom na gustoću travnjaka (P<0,001; H = 255 naprema M = 235 kg DM/cm/ha) i visinu trave (P<0,001; H = 14,8 naprema M = 10,9 cm). U drugom razdoblju, statistička značajnost i razlike između navedenih skupina iznosili su P<0,001; H = 216 naprema M = 196 kg DM/cm/ha i P<0,001; H = 14,3 naprema M = 13,0 cm. Najniža visina trave i najviša iskoristivost pašnjaka nakon napasivanja utvrđene su usporedbom niskog i visokog pašnog obroka tijekom prvog razdoblja (P<0,001; niski = 4,1 naprema visoki = 4,9 cm te P<0,001; niski = 98,8 naprema visoki = 89,9%) kao i tijekom drugog razdoblja (P<0,001; niski = 4,3 naprema visoki = 5,0 cm te P<0,001; niski = 97,1 naprema visoki = 89,9%). Sadržaj sirovih proteina i probavljivost organske tvari tijekom prvog razdoblja bili su viši kod pašnjaka sa srednjim prinosom pašnjaka prije napasivanja u odnosu na pašnjake s visokom razinom prinosa prije napasivanja (P<0,001; M = 210 naprema H = 176 g/kg DM i P<0,05; M = 846 naprema H = 836 g/kg DM. Tijekom drugog razdoblja, statistička značajnost i vrijednosti navedenih pokazatelja iznosili su (P<0,05; M = 212 naprema H = 192 g/kg DM i P<0,05; M = 828 naprema H = 821 g/kg DM). Navedeno se može pripisati većem udjelu lišća i manjem udjelu uvenule mase na pašnjacima sa srednjim prinosom prije napasivanja u odnosu na pašnjake s visokim prinosom prije napasivanja. Usporedba niskog i visokog pašnog obroka tijekom prvog razdoblja, pokazala je statistički značajne razlike za unos suhe tvari pašom (P<0,001; niski = 16,5 naprema visoki = 14,7 kg DM/krava/dnevno), proizvodnju mlijeka (P<0,01; niski = 23,8 naprema. visoki = 22,7 kg/day) te proizvodnju krute tvari mlijeka (P<0,05; niski = 1,69 naprema. visoki = 1,61 kg/krava). Tijekom drugog razdoblja, viši unos suhe tvari pašom utvrđen kod visokoga pašnog obroka u odnosu na niski pašni obrok (P<0,001; visoki = 15,7 naprema niski = 14,1 kg DM/krava/dnevno), viša je bila i proizvodnja mlijeka (P<0,001; visoki = 15,4 naprema niski = 13,6 kg/day) te proizvodnja krute tvari mlijeka (P<0,01; visoki = 1,19 naprema niski = 1,08 kg/krava). Najviša proizvodnja mlijeka po hektaru (P<0,001; 16,983 kg/ha) i krute tvari mlijeka po hektaru (1,268 kg/ha) utvrđena je kod krava koje su napasivane u skupini M20 travnjaka

    The ins and outs of the BCCAo model for chronic hypoperfusion: a multimodal and longitudinal MRI approach

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    Cerebral hypoperfusion induced by bilateral common carotid artery occlusion (BCCAo) in rodents has been proposed as an experimental model of white matter damage and vascular dementia. However, the histopathological and behavioral alterations reported in this model are variable and a full characterization of the dynamic alterations is not available. Here we implemented a longitudinal multimodal magnetic resonance imaging (MRI) design, including time- of-flight angiography, high resolution T1-weighted images, T2 relaxometry mapping, diffusion tensor imaging, and cerebral blood flow measurements up to 12 weeks after BCCAo or sham-operation in Wistar rats. Changes in MRI were related to behavioral performance in executive function tasks and histopathological alterations in the same animals. MRI frequently (70%) showed various degrees of acute ischemic lesions, ranging from very small to large subcortical infarctions. Independently, delayed MRI changes were also apparent. The patterns of MRI alterations were related to either ischemic necrosis or gliosis. Progressive microstructural changes revealed by diffusion tensor imaging in white matter were confirmed by observation of myelinated fiber degeneration, including severe optic tract degeneration. The latter interfered with the visually cued learning paradigms used to test executive functions. Independently of brain damage, BCCAo induced progressive arteriogenesis in the vertebrobasilar tree, a process that was associated with blood flow recovery after 12 weeks. The structural alterations found in the basilar artery were compatible with compensatory adaptive changes driven by shear stress. In summary, BCCAo in rats induces specific signatures in multimodal MRI that are compatible with various types of histological lesion and with marked adaptive arteriogenesis

    Barcelona City Council ICT Public Procurement Guide

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    Les mencions de responsabilitat s'han basat en els crèdits facilitats per l'àrea responsablePodeu consultar la versió en català a: http://hdl.handle.net/11703/106505Podeu consultar la versió en castellà a: http://hdl.handle.net/11703/115663Directrius per a definir el nou model de relació amb els proveïdors de tecnologia basat en el Codi de Pràctiques Tecnològique

    Guía de compra pública de TIC del Ayuntamiento de Barcelona

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    Les mencions de responsabilitat s'han basat en els crèdits facilitats per l'àrea responsablePodeu consultar la versió en català a: http://hdl.handle.net/11703/106505Podeu consultar la versió en anglès a: http://hdl.handle.net/11703/115664Directrius per a definir el nou model de relació amb els proveïdors de tecnologia basat en el Codi de Pràctiques Tecnològique

    Els nostres estàndards de serveis digitals

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    Les mencions de responsabilitat s'han basat en els crèdits facilitats per l'àrea responsableÉs part de la Mesura de govern per a la digitalització oberta : programari lliure i desenvolupament àgil de serveis a l'administració pública : Pla digital de la l'Ajuntament de Barcelona [http://hdl.handle.net/11703/106226]Conjunt de criteris per crear i gestionar serveis digitals per a la ciutadania de forma àgil i obert

    Codi de pràctiques tecnològiques de l'Ajuntament de Barcelona

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    Les mencions de responsabilitat s'han basat en els crèdits facilitats per l'àrea responsableÉs part de la Mesura de govern per a la digitalització oberta : programari lliure i desenvolupament àgil de serveis a l'administració pública : Pla digital de la l'Ajuntament de Barcelona [http://hdl.handle.net/11703/106226]Conjunt de directius per implementar projectes tecnològics amb estàndards oberts i gestió ètica de les dade

    Metodologies Agile a l'Ajuntament de Barcelona

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    Les mencions de responsabilitat s'han basat en els crèdits facilitats per l'àrea responsableÉs part de la Mesura de govern per a la digitalització oberta : programari lliure i desenvolupament àgil de serveis a l'administració pública : Pla digital de la l'Ajuntament de Barcelona [http://hdl.handle.net/11703/106226]Principis i pràctiques de transformació “Agile” de l’Ajuntament de Barcelona en matèria de tecnologia i innovaci
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