bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genetic analysis of live weight and ultrasonic fat and muscle traits in a hill sheep flock undergoing breed improvement utilizing an embryo transfer programme
Authors: Roden J. A. , Merrell B. G. , Murray W. A. , Haresign W. 
Published: May 2017

AbstractGenetic parameters for pre-weaning live weights and ultrasonic scanning measurements were estimated from a flock of Scottish Blackface sheep undergoing an embryo transfer programme. Maternal environmental effects could be evaluated without confounding with maternal genetic effects because embryos were transferred to unrelated recipient ewes. The data for the study were collected over a 7-year period (1993-1999) and related to a conventional hill farming system. The data were from 1465 lambs, the progeny of 60 sires, 263 donors and 784 recipient ewes. The only exception to the conventional farming system was at mating time when embryos were collected from selected donor ewes, following superovulation, and transferred to unrelated recipient ewes. Maternal environmental effects were important for birth weight (BW), 4-week weight (W4) and weaning weight (WW) but of less importance for ultrasonic fat depth (UFD), muscle depth (UMD) and muscle width (UMW). The heritabilities of the pre-weaning weights were moderate (0·17 to 0·23). The heritabilities of UFD and UMD were 0·44 and 0·27 respectively and were higher than found in previous similar studies. The heritability of UMW was low, 0·06. The genetic and phenotypic correlations among the pre-weaning weight traits were positive and moderate. There was a positive genetic ( + 0·25) and phenotypic ( + 0·24) correlation between UFD and UMD. The phenotypic and genetic correlations between BW and W4 and the scanning traits (UFD, UMD and UMW) were close to zero, and the correlations of WW with UFD, UMD and UMW were positive. The results of this study clearly demonstrate the importance of maternal environmental effects for lamb weights up to weaning and also suggest that genetic improvement for carcass composition in some populations of extensively reared hill sheep could be achieved more rapidly than previously thought possible.
Nutritional effects on the pituitary-ovarian axis during the early post-partum period in autumn-lambing ewes
Authors: Mitchell L. M. , Silveira M. , Ranilla M. J. , King M. E. , Gebbie F. E. , Robinson J. J. 
Published: May 2017

AbstractUsing primiparous autumn-lambing ewes, this study investigated nutritional effects on (i) pulsatile LH secretion, (ii) responsiveness of the pituitary-ovarian axis to exogenous GnRH, and (iii) oestrus and ovarian cyclicity during the early post-partum period. At lambing (25 October ± 0·3 days), 32 primiparous ewes rearing 2·1 ± 0·04 lambs were equally allocated to four dietary treatments in a 2 ✕ 2 factorial designed experiment. Diets comprised ad libitum hay and 1·5 kg per ewe per day of one of four concentrates (12·5 MJ metabolizable energy per kg dry matter) containing either fibrous (F) or starchy (S) ingredients with (P) or without (O) the inclusion of 120 g/kg fish meal. Throughout the study (lambing to 17 December) ewe body condition score was assessed and ewes and their lambs were weighed at weekly intervals. Blood samples were obtained from all ewes to measure circulating concentrations of progesterone and oestrous behaviour was monitored using vasectomized rams. On day 12 post partum, blood samples were obtained from all ewes at 2-h intervals (09:00 to 17:00 h) to measure concentrations of insulin and urea nitrogen, and at 15-min intervals (09:00 to 21:00 h) to measure pulsatile LH secretion. All ewes received 25 i. v. injections of GnRH (250 ng GnRH in 2 ml 0·9% saline) at 2-h intervals commencing 4 h before the end of the 15-min blood sampling period and their ovaries were examined via laparoscopy on day 17 post partum. There was no effect of dietary treatment on ewe live weight or body condition score throughout the study but inclusion of fish meal in the ewe diet increased lamb growth (FP/SP 255 (s.e. 8·9) v. FO/SO 234 (s.e. 8·2) g/day, P < 0·05). Circulating concentrations of insulin on day 12 post partum were lower in ewes given the fibrous compared with the starchy diets (P < 0·05) while dietary inclusion of fish meal increased (P < 0·001) urea nitrogen. Pulsatile LH secretion on day 12 post partum was not affected by dietary treatment. For ewes on diets F P, FO, SP and SO, the numbers that experienced an LH surge during the period of GnRH administration were 1, 2, 1 and 0, and that ovulated by day 17 post partum were 3, 5, 0 and 5 (FP/SP v. FO/SO, P < 0·05) respectively. Dietary treatment did not affect the intervals from parturition to the onset of ovarian cyclicity or oestrus (overall means were 23 (s.e.1·0) days and 38 (s.e.1·6) days respectively) but ewes on the fibrous compared with the starchy diet had a higher (P < 0·05) incidence of short (≤ 10 days) first ovarian cycles. Results of this study, which involved young growing animals, demonstrate that (i) inclusion of fish meal in the ewe diet influenced the sensitivity of the pituitary-ovarian axis to exogenous GnRH, and (ii) a fibrous compared with a starchy diet was associated with an increased incidence of premature luteal regression.
The effect of level and type of supplement offered to grazing dairy cows on herbage intake, animal performance and rumen fermentation characteristics
Authors: Sayers H. J. , Mayne C. S. , Bartram C. G. 
Published: May 2017

AbstractA study was undertaken to examine the effect of level and type of supplement and changes in the chemical composition of herbage through the grazing season on herbage intake, animal performance and rumen characteristics with high-yielding dairy cows. Thirty-two high genetic merit dairy cows were allocated to one of four treatments in a two-phase change-over design experiment. The four treatments involved offering either high-fibre (HF) or high-starch (HS) supplements at either 5 or 10 kg dry matter (DM) per day. Animals rotationally grazed perennial ryegrass swards offered a daily herbage allowance of 23 kg DM. High levels of animal performance were maintained throughout the study with mean milk yields over the 21-week experimental period of 35·5 and 37·2 kg per cow per day on the 5- and 10-kg treatments respectively. Supplement type had no significant effect on herbage intake. Increasing the level of supplementation reduced herbage intake by 0·49 and 0·46 kg herbage DM per kg supplement DM and increased milk yield, with a milk yield response of 0·55 and 0·65 kg/kg supplement DM offered in phases 1 and 2. Supplement type had no significant effect on milk yield and milk butterfat content. However, in both phases 1 and 2, milk protein content was significantly higher with cows offered the HS supplement compared with the HF supplement, this being particularly evident at the higher level of supplementation. Supplement type also had marked effects on milk protein composition. These results indicate that high levels of performance can be achieved with dairy cows on grazed pasture with moderate levels of supplementation.
Evaluation of growth rates and resistance to nematodes of Deccani and Bannur lambs and their crosses with Garole
Authors: Nimbkar C. , Ghalsasi P. M. , Swan A. A. , Walkden-Brown S. W. , Kahn L. P. 
Published: May 2017

AbstractSheep rearing is a traditional occupation of about 85 000 shepherd families on the Deccan plateau in the Maharashtra State of India. They rear Deccani (D) sheep which usually bear only single lambs. Prolificacy is an important trait for the efficiency of meat producing sheep. It was decided to evaluate and utilize Indian sheep genetic resources with a view to improving the efficiency of sheep production on the Deccan plateau. A crossbreeding experiment was conducted over 4 years, using rams of the D, Bannur (B) and Garole (G) breeds and D and B ewes with the aim of developing recommendations for the appropriate breed combination of a likely composite. It was found that crossing with G reduces live weight and growth rates significantly compared with D but lambs sired by G rams were more resistant to naturally acquired gastro-intestinal nematode infections and to artificial challenge with Haemonchus contortus than those sired by D or B rams. The G breed, being from a humid environment is, however, not adapted to the semi-arid Deccan plateau. The higher productivity (in terms of weight of lamb weaned) of twin-bearing ewes compared with those bearing singles was evident even in extensive rearing conditions. The finding of increased resistance to gastro-intestinal nematodes in the G breed, which also carries a major gene for prolificacy, highlights the potential for inclusion of G in a composite breed. Negative effects on growth and survival from inclusion of the Garole need to be carefully managed.
Changes in skin and fleece characteristics of Scottish cashmere goats following selection for increased annual production and decreased fibre diameter
Authors: Merchantt M. , Riach D. J. 
Published: May 2017

AbstractThe aim of this experiment was to determine the mechanisms involved in changes in the production of cashmere as a consequence of genetic selection. Skin follicle parameters and pattern of cashmere growth were compared in two selected lines of Scottish cashmere goats and a randomly bred control line. One line, the fine line, had been selected for low fibre diameter, and this had resulted in lower fibre diameter, but the weight of cashmere produced had also been reduced. Selection for fibre quantity and quality to give maximum financial return (the value line) had increased cashmere weight without a significant increase in cashmere diameter.Skin follicle density and the ratio of secondary to primary follicles (S/P ratio) were measured at 5 months of age in 25 female kids from each line. The density of follicles in the value line was greater (P · 0.05) than that in the fine or control lines (means were 21·8, 19·8 and 20·1 follicles per mm2 respectively, s.e.d. 0.73). S/P ratio increased (P · 0.001) from control to fine to value lines (means were 6.5, 7.7 and 8.4 respectively, s.e.d. = 0.30).The rate of cashmere growth (length), peak cashmere length, the duration of the cashmere growing period and dates of initiation and cessation of growth were measured in the same 25 goats from each line between 2 and 3 years of age. These traits were estimated from the regression of measurements of staple length taken at approximately 6-weekly intervals from the start of the growing period until peak staple length was reached. Measurements were made on the shoulder, mid side and hip. There was no difference in cashmere growth rate between the selection lines (average 0·29 (s.e. 0.006) mm/day). Cashmere growth started earliest in the value line and latest in the fine line but the date of cessation of growth was not different. This affected the duration of the growing period which was 183, 163 and 214 days (s.e.d. 9.6, P · 0.001) for the control, fine and value lines respectively. Peak staple length of cashmere was longest in the value line.Increased weight of cashmere in the value line was brought about through an increase in the number of secondary follicles and by an increase in the length of cashmere due to an increase in the duration of the growing period.
Eyesight: a study of the staff of a dental school
Authors: Chandler Nicholas P , Gray Andrew R , Murray Colleen M 
Published: May 2017

Abstract
Objectives/Aims:
The aim was to investigate the vision of all 90 dentally qualified staff at a dental school.

Materials and Methods:
Ethical approval was obtained and a questionnaire-based survey conducted. Data were screened and analysed using Stata 13.1. The χ2 and Fisher’s Exact tests were used to test for significance with an alpha level of 0.05.

Results:
The participation rate was 95.6%. Most of the teachers (92%) considered their eyesight was satisfactory to practice dentistry. Of the 97% who had been tested at some stage, 15% had their eye examination due to sight deterioration with 22% needing correction. Almost two-thirds were myopic and a third were hyperopic. Forty-nine per cent wore spectacles only, with about a quarter of this group alternating between spectacles and contact lenses. Of those with corrected vision, 80% followed their optometrist’s recall advice. Four participants reported that they were colour blind. While 4% had had laser-eye surgery, a further 27% were interested in this. Magnification was used by 72% with no significant differences between genders, age of staff member, place of qualification or registration status. Most of the staff (81%) thought that screening of dental student’s eyesight should be mandatory, and regular eye examinations as a condition of dental practice was supported by 67%.

Discussion:
The number of teachers reporting recent vision tests was encouraging; nevertheless, a worrying 8% surveyed were unsure if their eyesight was satisfactory for work. The commonest vision problem was myopia, with almost half of the teachers wearing spectacles. It is clear that visual standards for dentistry would be helpful. Magnification use was high, with many non-users indicating their intention to buy loupes.

Conclusions:
Within the limits of this study the teachers were conscientious regarding their eye care, irrespective of their training and age. There was strong support for the mandatory testing of vision for all dentists and especially dental students.
Characterising and predicting cyanobacterial blooms in an 8-year amplicon sequencing time course
Authors: Tromas Nicolas , Fortin Nathalie , Bedrani Larbi , Terrat Yves , Cardoso Pedro , Bird David , Greer Charles W , Shapiro B Jesse 
Published: May 2017

Abstract
Cyanobacterial blooms occur in lakes worldwide, producing toxins that pose a serious public health threat. Eutrophication caused by human activities and warmer temperatures both contribute to blooms, but it is still difficult to predict precisely when and where blooms will occur. One reason that prediction is so difficult is that blooms can be caused by different species or genera of cyanobacteria, which may interact with other bacteria and respond to a variety of environmental cues. Here we used a deep 16S amplicon sequencing approach to profile the bacterial community in eutrophic Lake Champlain over time, to characterise the composition and repeatability of cyanobacterial blooms, and to determine the potential for blooms to be predicted based on time course sequence data. Our analysis, based on 135 samples between 2006 and 2013, spans multiple bloom events. We found that bloom events significantly alter the bacterial community without reducing overall diversity, suggesting that a distinct microbial community—including non-cyanobacteria—prospers during the bloom. We also observed that the community changes cyclically over the course of a year, with a repeatable pattern from year to year. This suggests that, in principle, bloom events are predictable. We used probabilistic assemblages of OTUs to characterise the bloom-associated community, and to classify samples into bloom or non-bloom categories, achieving up to 92% classification accuracy (86% after excluding cyanobacterial sequences). Finally, using symbolic regression, we were able to predict the start date of a bloom with 78–92% accuracy (depending on the data used for model training), and found that sequence data was a better predictor than environmental variables.
Autotrophic and heterotrophic acquisition of carbon and nitrogen by a mixotrophic chrysophyte established through stable isotope analysis
Authors: Terrado Ramon , Pasulka Alexis L , Lie Alle A-Y , Orphan Victoria J , Heidelberg Karla B , Caron David A 
Published: May 2017

Abstract
Collectively, phagotrophic algae (mixotrophs) form a functional continuum of nutritional modes between autotrophy and heterotrophy, but the specific physiological benefits of mixotrophic nutrition differ among taxa. Ochromonas spp. are ubiquitous chrysophytes that exhibit high nutritional flexibility, although most species generally fall towards the heterotrophic end of the mixotrophy spectrum. We assessed the sources of carbon and nitrogen in Ochromonas sp. strain BG-1 growing mixotrophically via short-term stable isotope probing. An axenic culture was grown in the presence of either heat-killed bacteria enriched with 15N and 13C, or unlabeled heat-killed bacteria and labeled inorganic substrates (13C-bicarbonate and 15N-ammonium). The alga exhibited high growth rates (up to 2 divisions per day) only until heat-killed bacteria were depleted. NanoSIMS and bulk IRMS isotope analyses revealed that Ochromonas obtained 84–99% of its carbon and 88–95% of its nitrogen from consumed bacteria. The chrysophyte assimilated inorganic 13C-carbon and 15N-nitrogen when bacterial abundances were very low, but autotrophic (photosynthetic) activity was insufficient to support net population growth of the alga. Our use of nanoSIMS represents its first application towards the study of a mixotrophic alga, enabling a better understanding and quantitative assessment of carbon and nutrient acquisition by this species.
Diabetes-associated microbiota in fa/fa rats is modified by Roux-en-Y gastric bypass
Authors: Arora Tulika , Seyfried Florian , Docherty Neil G , Tremaroli Valentina , le Roux Carel W , Perkins Rosie , Bäckhed Fredrik 
Published: May 2017

Abstract
Roux-en-Y gastric bypass (RYGB) and duodenal jejunal bypass (DJB), two different forms of bariatric surgery, are associated with improved glucose tolerance, but it is not clear whether the gut microbiota contributes to this effect. Here we used fa/fa rats as a model of impaired glucose tolerance to investigate whether (i) the microbiota varies between fa/fa and nondiabetic fa/+ rats; (ii) the microbiota of fa/fa rats is affected by RYGB and/or DJB; and (iii) surgically induced microbiota alterations contribute to glucose metabolism. We observed a profound expansion of Firmicutes (specifically, Lactobacillus animalis and Lactobacillus reuteri) in the small intestine of diabetic fa/fa compared with nondiabetic fa/+ rats. RYGB-, but not DJB-, treated fa/fa rats exhibited greater microbiota diversity in the ileum and lower L. animalis and L. reuteri abundance compared with sham-operated fa/fa rats in all intestinal segments, and their microbiota composition resembled that of unoperated fa/+ rats. To investigate the functional role of RYGB-associated microbiota alterations, we transferred microbiota from sham- and RYGB-treated fa/fa rats to germ-free mice. The metabolic phenotype of RYGB-treated rats was not transferred by the transplant of ileal microbiota. In contrast, postprandial peak glucose levels were lower in mice that received cecal microbiota from RYGB- versus sham-operated rats. Thus, diabetes-associated microbiota alterations in fa/fa rats can be modified by RYGB, and modifications in the cecal microbiota may partially contribute to improved glucose tolerance after RYGB.
Structural basis for conductance through TRIC cation channels
Authors: Su Min , Gao Feng , Yuan Qi , Mao Yang , Li De-lin , Guo Youzhong , Yang Cheng , Wang Xiao-hui , Bruni Renato , Kloss Brian , Zhao Hong , Zeng Yang , Zhang Fa-ben , Marks Andrew R , Hendrickson Wayne A , Chen Yu-hang 
Published: May 2017

AbstractMammalian TRICs function as K+-permeable cation channels that provide counter ions for Ca2+ handling in intracellular stores. Here we describe the structures of two prokaryotic homologues, archaeal SaTRIC and bacterial CpTRIC, showing that TRIC channels are symmetrical trimers with transmembrane pores through each protomer. Each pore holds a string of water molecules centred at kinked helices in two inverted-repeat triple-helix bundles (THBs). The pores are locked in a closed state by a hydrogen bond network at the C terminus of the THBs, which is lost when the pores assume an open conformation. The transition between the open and close states seems to be mediated by cation binding to conserved residues along the three-fold axis. Electrophysiology and mutagenesis studies show that prokaryotic TRICs have similar functional properties to those of mammalian TRICs and implicate the three-fold axis in the allosteric regulation of the channel.
Emptying Dirac valleys in bismuth using high magnetic fields
Authors: Zhu Zengwei , Wang Jinhua , Zuo Huakun , Fauqué Benoît , McDonald Ross D. , Fuseya Yuki , Behnia Kamran 
Published: May 2017

AbstractThe Fermi surface of elemental bismuth consists of three small rotationally equivalent electron pockets, offering a valley degree of freedom to charge carriers. A relatively small magnetic field can confine electrons to their lowest Landau level. This is the quantum limit attained in other dilute metals upon application of sufficiently strong magnetic field. Here we report on the observation of another threshold magnetic field never encountered before in any other solid. Above this field, Bempty, one or two valleys become totally empty. Drying up a Fermi sea by magnetic field in the Brillouin zone leads to a manyfold enhancement in electric conductance. We trace the origin of the large drop in magnetoresistance across Bempty to transfer of carriers between valleys with highly anisotropic mobilities. The non-interacting picture of electrons with field-dependent mobility explains most results but the Coulomb interaction may play a role in shaping the fine details.
Out-of-plane chiral domain wall spin-structures in ultrathin in-plane magnets
Authors: Chen Gong , Kang Sang Pyo , Ophus Colin , N’Diaye Alpha T. , Kwon Hee Young , Qiu Ryan T. , Won Changyeon , Liu Kai , Wu Yizheng , Schmid Andreas K. 
Published: May 2017

AbstractChiral spin textures in ultrathin films, such as skyrmions or chiral domain walls, are believed to offer large performance advantages in the development of novel spintronics technologies. While in-plane magnetized films have been studied extensively as media for current- and field-driven domain wall dynamics with applications in memory or logic devices, the stabilization of chiral spin textures in in-plane magnetized films has remained rare. Here we report a phase of spin structures in an in-plane magnetized ultrathin film system where out-of-plane spin orientations within domain walls are stable. Moreover, while domain walls in in-plane films are generally expected to be non-chiral, we show that right-handed spin rotations are strongly favoured in this system, due to the presence of the interfacial Dzyaloshinskii–Moriya interaction. These results constitute a platform to explore unconventional spin dynamics and topological phenomena that may enable high-performance in-plane spin-orbitronics devices.
Antiferromagnetic CuMnAs multi-level memory cell with microelectronic compatibility
Authors: Olejník K. , Schuler V. , Marti X. , Novák V. , Kašpar Z. , Wadley P. , Campion R. P. , Edmonds K. W. , Gallagher B. L. , Garces J. , Baumgartner M. , Gambardella P. , Jungwirth T. 
Published: May 2017

AbstractAntiferromagnets offer a unique combination of properties including the radiation and magnetic field hardness, the absence of stray magnetic fields, and the spin-dynamics frequency scale in terahertz. Recent experiments have demonstrated that relativistic spin-orbit torques can provide the means for an efficient electric control of antiferromagnetic moments. Here we show that elementary-shape memory cells fabricated from a single-layer antiferromagnet CuMnAs deposited on a III–V or Si substrate have deterministic multi-level switching characteristics. They allow for counting and recording thousands of input pulses and responding to pulses of lengths downscaled to hundreds of picoseconds. To demonstrate the compatibility with common microelectronic circuitry, we implemented the antiferromagnetic bit cell in a standard printed circuit board managed and powered at ambient conditions by a computer via a USB interface. Our results open a path towards specialized embedded memory-logic applications and ultra-fast components based on antiferromagnets.