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ABSTRACT: The objectives were to test the effects of dietary vitamin D3 [cholecalciferol (CHOL)] compared with 25-hydroxyvitamin D3 [calcidiol (CAL)] on vitamin D status and response to an endotoxin challenge. Forty-five Holstein bull calves (5 ± 2 d of age) were blocked into weekly cohorts, fed a basal diet that provided 0.25 µg/kg body weight (BW) CHOL, and assigned randomly to 1 of 5 treatments: control [(CON) no additional vitamin D], 1.5 µg/kg BW CHOL (CHOL1.5), 3 µg/kg BW CHOL (CHOL3), 1.5 µg/kg BW CAL (CAL1.5), or 3 µg/kg BW CAL (CAL3). Calves were fed milk replacer until weaning at 56 d of age and had ad libitum access to water and starter grain throughout the experiment. Treatments were added daily to the diet of milk replacer until weaning and starter grain after weaning. Measures of growth, dry matter intake, and serum concentrations of vitamin D, Ca, Mg, and P were collected from 0 to 91 d of the experiment. At 91 d of the experiment, calves received an intravenous injection of 0.1 µg/kg BW lipopolysaccharide (LPS). Clinical and physiological responses were measured from 0 to 72 h relative to LPS injection. Data were analyzed with mixed models that included fixed effects of treatment and time, and random effect of block. Orthogonal contrasts evaluated the effects of (1) source (CAL vs. CHOL), (2) dose (1.5 vs. 3.0 µg/kg BW), (3) interaction between source and dose, and (4) supplementation (CON vs. all other treatments) of vitamin D. From 21 to 91 d of the experiment, mean BW of supplemented calves was less compared with CON calves, but the effect was predominantly a result of the CHOL calves, which tended to weigh less than the CAL calves. Supplementing vitamin D increased concentrations of 25-hydroxyvitamin D in serum compared with CON, but the increment from increasing the dose from 1.5 to 3.0 µg/kg BW was greater for CAL compared with CHOL (CON = 18.9, CHOL = 24.7 and 29.6, CAL = 35.6 and 65.7 ± 3.2 ng/mL, respectively). Feeding CAL also increased serum Ca and P compared with CHOL. An interaction between source and dose of treatment was observed for rectal temperature and derivatives of reactive metabolites after LPS challenge because calves receiving CHOL3 and CAL1.5 had lower rectal temperatures and plasma derivatives of reactive metabolites compared with calves receiving CHOL1.5 and CAL3. Supplementing vitamin D increased plasma P concentrations post-LPS challenge compared with CON, but plasma concentrations of Ca, Mg, fatty acids, glucose, β-hydroxybutyrate, haptoglobin, tumor necrosis factor-α, and antioxidant potential did not differ among treatments post-LPS challenge. Last, supplementing vitamin D increased granulocytes as a percentage of blood leukocytes post-LPS challenge compared with CON. Supplementing CAL as a source of vitamin D to dairy calves was more effective at increasing serum 25-hydroxyvitamin D, Ca, and P concentrations compared with feeding CHOL. Supplemental source and dose of vitamin D also influenced responses to the LPS challenge.

The γ-ray emission from the nuclei 62,64Fe following Coulomb excitation at bombarding energy of 400-440 AMeV was measured with special focus on E1 transitions in the energy region 4-8 MeV. The unstable neutron-rich nuclei 62,64Fe were produced at the FAIR-GSI laboratories and selected with the FRS spectrometer. The γ decay was detected with AGATA. From the measured γ-ray spectra the summed E1 strength is extracted and compared to microscopic quasi-particle phonon model calculations. The trend of the E1 strength with increasing neutron number is found to be fairly well reproduced with calculations that assume a rather complex structure of the 1− states (three-phonon states) inducing a strong fragmentation of the E1 nuclear response below the neutron binding energy.

Electric quadrupole matrix elements, Mp, for the Jπ=2+→0+, ΔT=0, T=1 transitions across the A=46 isobaric multiplet 46Cr-46V-46Ti have been measured at GSI with the FRS-LYCCA-AGATA setup. This allows direct insight into the isospin purity of the states of interest by testing the linearity of Mp with respect to Tz. Pairs of nuclei in the T=1 triplet were studied using identical reaction mechanisms in order to control systematic errors. The Mp values were obtained with two different methodologies: (i) a relativistic Coulomb excitation experiment was performed for 46Cr and 46Ti; (ii) a “stretched target” technique was adopted here, for the first time, for lifetime measurements in 46V and 46Ti. A constant value of Mp across the triplet has been observed. Shell-model calculations performed within the fp shell fail to reproduce this unexpected trend, pointing towards the need of a wider valence space. This result is confirmed by the good agreement with experimental data achieved with an interaction which allows excitations from the underlying sd shell. A test of the linearity rule for all published data on complete T=1 isospin triplets is presented.

White-nose syndrome (WNS) has rendered four of Ontario's species endangered, while leaving the other four species relatively unaffected. The causes and extent of the declines have been widely studied. The influence on remaining bat species has not. Comparing acoustic data recorded -10 years apart, we evaluated how species in southeastern Ontario, Canada, use different foraging habitats pre- and post-WNS detection. We observed activity declines in now-endangered species over open fields (small-footed myotis, Myotis leibii (Audubon and Bachman, 1842); little brown bat, Myotis lucifugus (Le Conte, 1831); northern myotis, Myotis septentrionalis (Trouessart, 1897); tricolored bat, Perimyotis subflavus (F. Cuvier, 1832)) and speculate that the reduction of the once most common species (M. lucifugus) may have resulted in other species searching for prey in habitat once dominated by M. lucifugus. That is, these changes may have allowed greater presence in open field and clutter or edge environments by the big brown bat (Eptesicusfuscus (Palisot de Beauvois, 1796)) and three migratory species (silver-haired bat, Lasionycteris noctivagans (Le Conte, 1831); red bat, Lasiurus borealis (Muller, 1776); hoary bat, Lasiurus cinereus (Palisot de Beauvois, 1796)). However, our results also suggest that (i) while the decline of most resident bat species due to WNS may have relaxed competition for relatively unaffected species in some, but not all habitats, that (ii) sensory and biomechanical constraints may limit prey exploitation by these less-affected bat species in these habitats. Key words: white-nose syndrome, Pseudogymnoascus destructans, niche release, interspecific competition, Myotis lucifugus, little brown bat, Eptesicus fuscus, big brown bat. Le syndrome du museau blanc (SMB) a mis quatre especes en voie de disparition en Ontario, les quatre autres especes etant relativement peu touchees. Si les causes et l'etendue de ces declins ont ete largement etudiees, l'influence du SMB sur les autres especes de chauves-souris ne l'a pas ete. En comparant des donnees acoustiques enregistrees a environ 10 annees d'intervalle, nous evaluons les utilisations faites par differentes especes dans le sud-est de l'Ontario (Canada) d'habitats d'approvisionnement avant et apres la detection du SMB. Nous observons des baisses d'activite au-dessus de champs ouverts chez les especes aujourd'hui en voie de disparition (chauve-souris pygmee, Myotis leibii (Audubon et Bachman, 1842); vespertilion brun, Myotis lucifugus (Le Conte, 1831); vespertilion nordique, Myotis septentrionalis (Trouessart, 1897); pipistrelle de l'Est, Perimyotis subflavus (F. Cuvier, 1832)) et postulons que le declin de l'espece auparavant la plus repandue (M. lucifugus) pourrait avoir mener d'autres especes a chercher des proies dans des habitats ou ce dernier etait autrefois dominant. Autrement dit, ces changements pourraient avoir permis une plus grande presence dans les milieux de champ ouvert et de fouillis ou de bordure de la serotine brune (Eptesicusfuscus (Palisot de Beauvois, 1796)) et de trois especes migratrices (chauve-souris argentee, Lasionycteris noctivagans (Le Conte, 1831); chauve-souris rousse, Lasiurus borealis (Muller, 1776); chauve-souris cendree, Lasiurus cinereus (Palisot de Beauvois, 1796)). Cependant, nos resultats indiqueraient aussi que (i) si le declin de la plupart des especes de chauves-souris residentes en raison du SMB pourrait avoir attenue la concurrence pour des especes relativement non affectees dans certains, mais non tous les habitats, (ii) des contraintes sensorielles et biomecaniques pourraient limiter l'exploitation de proies dans ces habitats par ces especes moins affectees. [Traduit par la Redaction] Mots-cles : syndrome du museau blanc, Pseudogymnoascus destructans, liberation de la niche, concurrence interspecifique, Myotis lucifugus, vespertilion brun, Eptesicusfuscus, serotine brune., Introduction Bat communities are rarely monospecific and local assemblages can include over 100 bat species in equatorial regions of Africa, Asia, and South America (Fenton and Ratcliffe 2010). Even in [...]