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Current techniques for measuring the dry matter intake (DMI) of grazing lactating beef cows are invasive, time consuming and expensive making them impractical for use on commercial farms. This study was undertaken to explore the potential to develop and validate a model to predict DMI of grazing lactating beef cows, which could be applied in a commercial farm setting, using non-invasive animal measurements. The calibration dataset used to develop the model was comprised of 94 measurements recorded on 106 beef or beef–dairy crossbred cows (maternal origin). The potential of body measurements, linear type scoring, grazing behaviour and thermal imaging to predict DMI in combination with known biologically plausible adjustment variables and energy sinks was investigated. Multivariable regression models were constructed for each independent variable using SAS PROC REG and contained milk yield, BW, parity, calving day and maternal origin (dairy or beef). Of the 94 variables tested, 32 showed an association with DMI (P < 0.25) upon multivariable analysis. These variables were incorporated into a backwards linear regression model using SAS PROC REG. Variables were retained in this model if P < 0.05. Five variables; width at pins, full body depth, ruminating mastications, central ligament and rump width score, were retained in the model in addition to milk yield, BW, parity, calving day and maternal origin. The inclusion of these variables in the model increased the predictability of DMI by 0.23 (R2 = 0.68) when compared to a model containing milk yield, BW, parity, calving day and maternal origin only. This model was applied to data recorded on an independent dataset; a herd of 60 lactating beef cows two years after the calibration study. The R2 for the validation was 0.59. Estimates of DMI are required for measuring feed efficiency. While acknowledging challenges in applicability, the findings suggest a model such as that developed in this study may be used as a tool to more easily and less invasively estimate DMI on large populations of commercial beef cows, and therefore measure feed efficiency.
Corruption of public officials is the silent killer of the U.S. economy, and we should reflect carefully on how it might be reined in. That’s the thought behind campaign finance laws. But broad grants of discretion to authorities, which might work in New Zealand, are more likely to be abused in low-trust America, and campaign finance laws are one example of this. First Amendment free speech rights, as interpreted by the Supreme Court, represent its reflection on the American character and the possibility of abuse when Congress tries to restrict political speech. So conservatives are apt to think, and not entirely without reason.
Insufficient vitamin D during pregnancy increases risk of adverse outcomes, with known differences by race/ethnicity. We sought to determine whether predictors of vitamin D insufficiency vary by race/ethnicity in an ethnically diverse pregnancy cohort. Plasma 25-hydroxyvitamin D concentrations and patient characteristics were measured at first prenatal visit to prenatal clinics in south-eastern USA between 2009 and 2011 (n 504). Prevalence ratios (PR) and 95 % CI were estimated using multivariable regression to quantify predictors of vitamin D insufficiency, overall and by race/ethnicity. In race/ethnicity-stratified models, season was most associated with vitamin D insufficiency among non-Hispanic white women; PR for winter v. summer were 3·58 (95 % CI 1·64, 7·81) for non-Hispanic white, 1·52 (95 % CI 1·18, 1·95) for Hispanic and 1·14 (95 % CI 0·99, 1·30) for non-Hispanic black women. Although women with darker skin tones are most vulnerable to prenatal vitamin D insufficiency, season may be more strongly associated with insufficiency among women with lighter skin tones.
Large, ‘complex’ pre-Neolithic hunter-gatherer communities thrived in southern China and northern Vietnam, contemporaneous with the expansion of farming. Research at Con Co Ngua in Vietnam suggests that such hunter-gatherer populations shared characteristics with early farming communities: high disease loads, pottery, complex mortuary practices and access to stable sources of carbohydrates and protein. The substantive difference was in the use of domesticated plants and animals—effectively representing alternative responses to optimal climatic conditions. The work here suggests that the supposed correlation between farming and a decline in health may need to be reassessed.
The objective of this study was to investigate the effect of both cow genetic index (CGI) and feeding system on the performance of second lactation Holstein-Friesian dairy cows on grass-based feeding systems. There was no interaction between CGI and feeding system for any of the parameters measured. Cows of high genetic index (HGI) produced significantly higher yields of milk (P < 0.001), fat (P < 0.001) protein (P < 0.0001) and lactose (P < 0.001) than medium genetic index cows (MGI). CGI had no effect on the concentration of milk constituents. Averaged across four intake measurements the HGI cows had significantly (P < 0.001) higher grass dry-matter intake (GDMI) and total dry-matter intake (TDMI). Live weight was similar for both genotypes during lactation. The HGI cows had significantly (P < 0.05) higher live-weight loss in the first 10 weeks of lactation, significantly lower live-weight gain from week 10 to the end of lactation and higher (P < 0.05) live-weight gain during the dry period. Condition score was significantly lower with the HGI (P < 0.001) at all stages of lactation. There was a higher proportion (P < 0.05) of the HGI cows non-pregnant at the end of the 13-week breeding season. Feeding system had a significant effect on the yield of milk (P < 0.001), fat (P < 0.001), protein (P < 0.001) and lactose (P < 0.001). Feeding system B produced significantly higher (P < 0.05) milk yield and yield of constituents (when compared with feeding systems A and C). Over the period when feeding systems were being applied, feeding system C had significantly higher (P < 0.05) milk protein concentration. Feeding system had a significant effect (P < 0.001) on both GDMI and TDMI. Feeding system had no effect on live weight, condition score or fertility performance.
The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (~2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.
Cull cows comprise about 44% of all cattle slaughtered at Irish meat factories in 2006; which was an increase of 6% from 2005. Between September and December 2006, 18% of cull cows failed to achieve P+3 carcass classification compared with 12% for the remainder of the year (DAF, 2006). There is a large proportion of cows slaughtered in November, which suggests that unfit (low bodyweight and condition score) cows are being presented for slaughter at the end of lactation without finishing prior to slaughter. Farmers who are finish feeding cull cows have an interest in alternative feeding regimes i.e. pasture and/or forage use for a more economical beef supply due to increasing concentrate costs, however present farm practice and culling decisions made by the dairy farmer often excludes this as a real possibility. The objective of this study was to compare days to slaughter, average daily gain, and final live and carcass of cull dairy cows subjected to four over-wintering strategies prior to a pasture based finishing diet.
Interest is accruing in indicator traits as predictors of fertility which: 1) can be more easily recorded; 2) can be measured early in life; and, 3) possess a co-heritability that is larger than the heritability of the fertility traits. Potentially interesting indicator traits include body condition score (BCS) and body weight (BW). The objective of this study was to estimate genetic (co) variances between BCS, BCS change, BW, BW change, and fertility traits in dairy cattle.
Pre-1990 published responses to supplementation at pasture ranged from 0.4 to 0.6kg milk/kg concentrate fed. However since 1990 higher responses to concentrate supplementation at pasture have been published (Delaby 2001). The objective of this study was to determine if milk production responses of Holstein-Friesian dairy cows to concentrate supplementation at pasture are influenced by genetic merit (milk yield potential) in a spring calving grass based system of milk production.
In recent years the relevance of continued selection for higher milk yield alone has been questioned for three reasons (Simm, 1998): 1) the introduction of milk quotas in some countries, 2) the now well documented deleterious effect of selection for yield on health and fertility (Pryce and Veerkamp, 2001), and, 3) the increased emphasis in payment schemes in many countries on milk composition. The purpose of this study was to measure the biological efficiency of two dual-purpose breeds (Montbeliarde (MB) and Normande (NR)) relative to two Holstein-Friesian strains (upgraded Irish Holstein-Friesian (CL) and Dutch Holstein-Friesian (HF)) on a spring-calving milk production system based mainly on grazed grass as a feed.
OBJECTIVES/SPECIFIC AIMS: Cocaine use is a significant health problem in the United States and associated with increased risk of adverse cardiovascular outcomes. Our goal was to evaluate the effects of rapid cocaine infusions on cardiovascular hemodynamics among patients with cocaine abuse disorder. METHODS/STUDY POPULATION: Patients with a history of cocaine abuse but no overt cardiovascular disease received 4 consecutive intravenous infusions of cocaine (0, 10, 20, 40 mg) given in randomized, double-blinded order. The infusion procedure was repeated on 2 consecutive days (4 infusions each day). Following each dose, patients underwent continuous monitoring via fingertip plethysmography for 30 minutes, followed by an additional 30 minutes washout procedure. Patients were surveyed throughout this timeline to record symptoms of cocaine response. Finger tracings were then used to calculate arterial pressure curves and parameters of heart rate, blood pressure, cardiac output, stroke volume, and systemic vascular resistance according to device-specific algorithms. Mean values were calculated over the entire 30 minutes follow-up and peak values were defined as the maximum value sustained over any 60-second interval during the follow-up period. RESULTS/ANTICIPATED RESULTS: Seven patients were enrolled and received cocaine infusions of 2 consecutive days. Cocaine dose was positively associated with mean cardiac output (R=0.489, p<0.001), peak diastolic blood pressure (R=0.435, p=0.001), mean heart rate (R=0.401, p=0.003), peak systolic blood pressure (R=0.399, p=0.003), peak mean arterial pressure (R=0.362, p=0.008), mean systolic blood pressure (R=0.399, p=0.003), +dP/dt (R=0.346, p=0.012), and peak heart rate (R=0.334, p=0.015). Hemodynamic parameters were also predictive of patient-reported symptoms of cocaine response. DISCUSSION/SIGNIFICANCE OF IMPACT: These data confirm the known pharmacologic effect of cocaine to prevent reuptake of neurotransmitters and demonstrate the feasibility of conducting a noninvasive assessment of cardiovascular hemodynamics as a measure of responsiveness to cocaine infusions. This procedure also provides a benchmark to evaluate the potential impact of pharmacologic treatments on cocaine-induced hemodynamic changes and patient perceptions of cocaine response.
Using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), it was shown for four different types of carbon that electrode treatments at negative potentials enhance the kinetics of VIV-VV and inhibit the kinetics of VII-VIII while electrode treatments at positive potentials inhibit the kinetics of VIV-VV and enhance the kinetics of VII-VIII. These observations may explain conflicting reports in the literature. The potentials required for activation and deactivation of electrodes were examined in detail. The results suggest that interchanging the positive and negative electrodes in a vanadium flow battery (VFB) would reduce the overpotential at the negative electrode and so improve the performance. This is supported by flow-cell experiments. Thus, periodic catholyte-anolyte interchange, or equivalent alternatives such as battery overdischarge, show promise of improving the voltage efficiency of VFBs.
Converging evidence suggests that subjective cognitive concerns (SCC) are associated with biomarker evidence of Alzheimer's disease (AD) prior to objective clinical impairment. However, the sensitivity of SCC reports in early AD may be biased by demographic factors. Here, we sought to investigate whether age, education, and sex influence the relationship between SCC and amyloid (Aβ) burden.
In this cross-sectional study, we examined 252 clinically normal (CN) individuals (57.7% females) enrolled in the Harvard Aging Brain Study, ages 63–90 years (mean 73.7±6) with 6–20 years of education (mean 15.8±3). SCC was assessed as a composite score comprising three questionnaires. Cortical Aβ burden was assessed with Pittsburgh compound B positron emission tomography imaging. A series of linear regression models assessed the potential modifying role of demographic variables with respect to Aβ burden and SCC. A post-hoc mediation model was implemented to further understand the relationship between Aβ burden and SCC via their relationship with education.
Age (β = −0.84, p = 0.36) and sex (β = −0.55, p = 0.22) did not modify the relationship between SCC and Aβ burden. Fewer years of education was correlated with greater SCC (r = −0.12, p = 0.05), but the relationship between Aβ burden and SCC was stronger in those with more education (β = 1.16, p < 0.05). A partial mediation effect was found of Aβ burden on SCC via education (b = −0.12, 95% CI [−0.31, −0.02]).
These findings suggest that the association between SCC and Aβ burden becomes stronger with greater educational attainment. Thus, SCC may be of particular importance in highly educated CN individuals harboring amyloid pathology.
The Dark Energy Survey is undertaking an observational programme imaging 1/4 of the southern hemisphere sky with unprecedented photometric accuracy. In the process of observing millions of faint stars and galaxies to constrain the parameters of the dark energy equation of state, the Dark Energy Survey will obtain pre-discovery images of the regions surrounding an estimated 100 gamma-ray bursts over 5 yr. Once gamma-ray bursts are detected by, e.g., the Swift satellite, the DES data will be extremely useful for follow-up observations by the transient astronomy community. We describe a recently-commissioned suite of software that listens continuously for automated notices of gamma-ray burst activity, collates information from archival DES data, and disseminates relevant data products back to the community in near-real-time. Of particular importance are the opportunities that non-public DES data provide for relative photometry of the optical counterparts of gamma-ray bursts, as well as for identifying key characteristics (e.g., photometric redshifts) of potential gamma-ray burst host galaxies. We provide the functional details of the DESAlert software, and its data products, and we show sample results from the application of DESAlert to numerous previously detected gamma-ray bursts, including the possible identification of several heretofore unknown gamma-ray burst hosts.
Information on the genetic diversity and population structure of cattle breeds is useful when deciding the most optimal, for example, crossbreeding strategies to improve phenotypic performance by exploiting heterosis. The present study investigated the genetic diversity and population structure of the most prominent dairy and beef breeds used in Ireland. Illumina high-density genotypes (777 962 single nucleotide polymorphisms; SNPs) were available on 4623 purebred bulls from nine breeds; Angus (n=430), Belgian Blue (n=298), Charolais (n=893), Hereford (n=327), Holstein-Friesian (n=1261), Jersey (n=75), Limousin (n=943), Montbéliarde (n=33) and Simmental (n=363). Principal component analysis revealed that Angus, Hereford, and Jersey formed non-overlapping clusters, representing distinct populations. In contrast, overlapping clusters suggested geographical proximity of origin and genetic similarity between Limousin, Simmental and Montbéliarde and to a lesser extent between Holstein, Friesian and Belgian Blue. The observed SNP heterozygosity averaged across all loci was 0.379. The Belgian Blue had the greatest mean observed heterozygosity (HO=0.389) among individuals within breed while the Holstein-Friesian and Jersey populations had the lowest mean heterozygosity (HO=0.370 and 0.376, respectively). The correlation between the genomic-based and pedigree-based inbreeding coefficients was weak (r=0.171; P<0.001). Mean genomic inbreeding estimates were greatest for Jersey (0.173) and least for Hereford (0.051). The pair-wise breed fixation index (Fst) ranged from 0.049 (Limousin and Charolais) to 0.165 (Hereford and Jersey). In conclusion, substantial genetic variation exists among breeds commercially used in Ireland. Thus custom-mating strategies would be successful in maximising the exploitation of heterosis in crossbreeding strategies.
Patients experiencing a first psychotic episode or early stages of psychosis present with key diagnostic issues for clinicians. At the time of first-episode psychosis presentation, it is crucial that clinicians select the most effective treatment option as immediate intervention offers the best chance for containing the illness. Functional impairment occurs most rapidly at the early stage of illness, and such impairment can influence the patient's future prognosis, alter the level of necessary treatment, and affect morbidity. Although research has shown a decrease in brain gray matter as well as signs of functional impairment in those who develop psychosis, many of these patients remain untreated for extended periods of time and do not visit a clinician due to fear of stigma, a failure to recognize the problem, or complexities of their care system. Prior studies have shown that untreated psychosis results in worse outcome for patients compared to psychosis that is treated earlier in the course of illness. There is a range of treatment options for psychosis, including use of first-generation or second-generation antipsychotic medication. Clinicians should note that both medication types are associated with certain side effects, such as tardive dyskinesia and weight gain, respectively. For all antipsychotics, doses should be lower for patients with a first psychotic episode than for patients with chronic psychosis. Finally, clinicians must consider that patients may present with various comorbidities, such as substance abuse, that also may affect treatment.
This expert roundtable supplement will address the diagnosis and treatment selection for first-episode psychosis as well as comorbidities related to the condition. The use of first- or second-generation antipsychotics for psychosis treatment, dosing guidelines, and the antipsychotic side-effect profile will also be addressed.
Intervention in the progression of schizophrenia is an effort not just to deter psychosis but also to protect the brain from physiologic deterioration. Neurodegeneration is believed to result from neurochemical dysregulation during the onset of schizophrenia. Deterioration accrued over recurring psychotic episodes causes cumulative loss of cell processes, loss of gray matter volume, and apoptosis. Neurodegeneration ultimately results in persistent symptomology and functional impairment. Functional decline occurs early in the course of schizophrenia, and the symptoms that emerge during the prodromal stage may derail the normal adolescent neurodevelopment. Both first-episode psychosis and the prodrome may be opportunities to forestall neurodegeneration. Unfortunately, people with schizophrenia often experience a long duration of untreated psychosis. Treatment of first-episode psychosis with antipsychotic agents shows robust response. However, early-stage patients have very high rates of medication noncompliance. Treatment in the prodrome may offer the best chance to delay the onset of illness, mitigate its severity after onset, or even prevent onset of symptoms entirely. Nonpharmacologic treatments during the prodrome, such as education, treatment for substance use, and cognitive-behavioral therapy, are low-risk interventions that are potentially beneficial. Pharmacologic interventions during the prodrome are also effective in delaying onset of illness, but carry the risk of adversely affecting patients who are false positives for prodromal schizophrenia.
In this Expert Roundtable Supplement, Jeffrey A. Lieberman, MD, provides an overview of the neurobiological basis of neurodegeneration and the concept of neuroprotection. Next, Peter F. Buckley, MD, reviews the importance of first-episode psychosis, including duration of untreated illness and medication adherence. Finally, Diana O. Perkins, MD, MPH, reviews treatment strategies for prodromal schizophrenia.
Autobiographical memory (ABM), personal semantic memory (PSM), and autonoetic consciousness are affected in individuals with mild cognitive impairment (MCI) but their relationship with Alzheimer's disease (AD) biomarkers are unclear.
Forty-five participants (healthy controls (HC) = 31, MCI = 14) completed the Episodic ABM Interview and a battery of memory tests. Thirty-one (HC = 22, MCI = 9) underwent β-amyloid positron emission tomography (PET) and magnetic resonance (MR) imaging. Fourteen participants (HC = 9, MCI = 5) underwent one imaging modality.
Unlike PSM, ABM differentiated between diagnostic categories but did not relate to AD biomarkers. Personal semantic memory was related to neocortical β-amyloid burden after adjusting for age and apolipoprotein E (APOE) ɛ4. Autonoetic consciousness was not associated with AD biomarkers, and was not impaired in MCI.
Autobiographical memory was impaired in MCI participants but was not related to neocortical amyloid burden, suggesting that personal memory systems are impacted by differing disease mechanisms, rather than being uniformly underpinned by β-amyloid. Episodic and semantic ABM impairment represent an important AD prodrome.