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1.
Transl Anim Sci ; 7(1): txad043, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37250343

RESUMO

The objective of this study was to develop near infrared spectroscopy (NIRS) calibrations to predict fecal nutrient composition, intake, and diet digestibility from beef cattle fed high forage diets. Heifers were fed 12 different forage-based diets (>95% forage dry matter basis) in 3 total collection digestibility studies, resulting in individual fecal samples and related spectra (n = 135), corresponding nutrient intake, and apparent total tract digestibility (aTTD) data. Fecal samples were also collected from steers grazing two annual and two perennial forage mixtures over two growing seasons. Samples (n = 13/paddock) were composited by paddock resulting in 30 samples from year 1, and 24 from year 2. The grazing fecal spectra (n = 54) were added to the existing fecal composition spectral library. Dried and ground fecal samples were scanned using a FOSS DS2500 scanning monochromator (FOSS, Eden Prairie, MN). Spectra were mathematically treated for detrend and scatter correction and modified partial least squares (MPLS) regression was performed. The coefficient of determination for cross validation (R2cv) and standard error of cross validation (SECV) were used to evaluate the quality of calibrations. Prediction equations were developed for fecal composition [organic matter (OM), nitrogen (N), amylase-treated ash-corrected neutral detergent fiber (aNDFom), acid detergent fiber (ADF), acid detergent lignin (ADL), undigestible NDF after 240 h of in vitro incubation (uNDF), calcium (Ca), and phosphorus (P)], digestibility [DM, OM, aNDFom, N], and intake [DM, OM, aNDFom, N, uNDF]. The calibrations for fecal OM, N, aNDFom, ADF, ADL, uNDF, Ca, P resulted in R2cv between 0.86 and 0.97 and SECV of 1.88, 0.07, 1.70, 1.10, 0.61, 2.00, 0.18, and 0.06, respectively. Equations predicting intake of DM, OM, N, aNDFom, ADL, and uNDF resulted in R2cv values between 0.59 and 0.91, SECV values of 1.12, 1.10, 0.02, 0.69, 0.06, 0.24 kg·d-1, respectively, and SECV values between 0.00 and 0.16 when expressed as % body weight (BW). Digestibility calibrations for DM, OM, aNDFom, and N resulted in R2cv ranging from 0.65 to 0.74 and SECV values from 2.20 to 2.82. We confirm the potential of NIRS to predict fecal chemical composition, digestibility, and intake of cattle fed high forage diets. Future steps include validation of the intake calibration equations for grazing cattle using forage internal marker and modelling energetics of grazing growth performance.

2.
Toxins (Basel) ; 14(9)2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-36136518

RESUMO

As the contamination of cereal grains with ergot has been increasing in Western Canada, studies were undertaken to evaluate the impacts of heating (60, 80, 120, or 190 °C) alone or in combination with pelleting on concentrations of ergot alkaloids. Fifteen samples of ergot-contaminated grain from Alberta and Saskatchewan were assayed for R and S epimers of six alkaloids (ergocryptine, ergocristine, ergocornine, ergometrine, ergosine, and ergotamine) using HPLC MS/MS. Five samples with distinct alkaloid profiles were then selected for heating and pelleting studies. Heating resulted in a linear increase (p < 0.05) of total R and total S epimers with increasing temperature, although some individual R epimers were stable (ergometrine, ergosine, ergotamine). Pelleting also increased (p < 0.05) concentrations of total R and total S epimers detected, although ergometrine concentration decreased (p < 0.05) after pelleting. A feeding study arranged in a 2 × 2 factorial structure used 48 backgrounding Angus-cross steers fed four different diets: (1) Control Mash (CM, no added ergot), (2) Control Pellet (CP), (3) Ergot Mash (EM), or (4) Ergot Pellet (EP). Pelleting heated the ergot to 90−100 °C under 4 bars pressure, but the ergot used in the feeding study was not otherwise heated. Alkaloid concentrations of EM and EP varied by up to 1.1 mg/kg depending on the feed matrix assayed. No differences among treatments were noted for growth performance, feed intake, feed conversion, concentrations of serum prolactin and haptoglobin, hair cortisol, or in temperatures of extremities measured by infrared thermography. The only negative impacts of ergot alkaloids were on blood parameters indicative of reduced immune function or chronic inflammation. Pelleting did not heighten the negative clinical outcomes of ergot, although alkaloid concentrations of pelleted feed increased depending on the matrix assayed. It was hypothesized that the heat and pressure associated with pelleting may enhance the recovery of alkaloids from pelleted feed.


Assuntos
Claviceps , Alcaloides de Claviceps , Alberta , Ração Animal/análise , Animais , Bovinos , Claviceps/química , Grão Comestível/química , Ergonovina/análise , Alcaloides de Claviceps/análise , Ergotamina/análise , Ergotaminas/análise , Haptoglobinas/análise , Calefação , Hidrocortisona , Prolactina , Espectrometria de Massas em Tandem/métodos
3.
Toxins (Basel) ; 10(8)2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30071666

RESUMO

As contamination with cereal ergot has been increasing in western Canada, this study evaluated impacts of feeding a mycotoxin binder (Biomin® II; BB) on nutrient digestibility, alkaloid recovery in feces, and lamb growth performance. Forty-eight ram lambs (25.9 ± 1.4 kg) were randomly assigned to one of four barley-based diets: Control (C), no added alkaloids, Control + BB fed at 30 g/head per day (CBB); Ergot, 2564 ppb total R + S epimers (E); Ergot + BB, 2534 ppb R + S epimers (EBB). Lambs were fed ab libitum for up to 11 weeks until slaughter at >46 kg live weight. Both average daily gain (ADG) and gain/feed ratio were greater (p < 0.01) for lambs fed C and CBB diets as compared with those containing added ergot, although dry matter intake was not affected by dietary ergot or BB. Serum prolactin concentrations were two times higher in EBB- compared with E-fed lambs (p < 0.05), although both were lower than in C or CBB (p < 0.001) lambs. Rectal temperatures were greater in lambs receiving dietary ergot (p ≤ 0.001) than in C- and CBB-fed lambs. In a digestibility study using eight ram lambs, treatment with BB increased neutral detergent fiber (NDF) digestibility (p = 0.01). Nitrogen retention (g) was greater (p < 0.05) for lambs receiving C or CBB compared with ergot-contaminated diets. Feces of EBB lambs had 38.5% greater (p < 0.001) recovery of alkaloids compared with those fed E. Based on sparing of prolactin, BB may reduce impacts of ergot alkaloids by increasing their excretion in feces. Accordingly, concentrations of dietary alkaloids, which would not harm sheep, would be increased by feeding BB.


Assuntos
Digestão/efeitos dos fármacos , Alcaloides de Claviceps/farmacocinética , Fezes/química , Micotoxinas/farmacocinética , Substâncias Protetoras/administração & dosagem , Ração Animal , Animais , Dieta/veterinária , Grão Comestível , Alcaloides de Claviceps/química , Contaminação de Alimentos , Hordeum , Masculino , Micotoxinas/química , Nutrientes/administração & dosagem , Prolactina/sangue , Substâncias Protetoras/química , Ovinos
4.
Toxins (Basel) ; 9(12)2017 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-29257065

RESUMO

Allowable limits for cereal ergot alkaloids in livestock feeds are being re-examined, and the objective of this study was to compare nutrient digestibility, growth performance and carcass characteristics of ram lambs fed a range of alkaloid concentrations, including the maximum currently allowed in Canada (2 to 3 ppm). Four pelleted diets were fed: control, with no added alkaloids; 930; 1402; and 2447 ppb alkaloids based on total R and S epimers. Eight ram lambs (30.0 ± 3.1 kg) were used to examine the impacts of dietary treatments on nutrient digestibility and alkaloid recovery from feces. Concentrations of dietary alkaloids evaluated did not affect nutrient digestibility or N metabolism. Excepting ergocornine and ergocryptine, recovery of alkaloids in feces varied among periods, suggesting that individual lambs may differ in their ability to metabolize ergocristine, ergometrine, ergosine, ergotamine and their S epimers. In a second experiment, ram lambs (n = 47, 30 ± 8 kg) were randomly assigned to a diet and weighed weekly until they achieved a slaughter weight of ≥ 45 kg (average 9 weeks; range 6 to 13 weeks). Intake of DM did not differ (p = 0.91) among diets, although lambs fed 2447 ppb alkaloids had a lower (p < 0.01) ADG than did lambs receiving other treatments. The concentration of serum prolactin linearly declined (p < 0.01) with increasing alkaloids. Feeding 2447 ppb total alkaloids negatively impacted growth, while feeding 1402 ppb did not harm growth performance, but reduced carcass dressing percentage. Due to different concentrations of alkaloids affecting growth and carcass characteristics in the present study, determining allowable limits for total dietary alkaloids will require a better understanding of impacts of alkaloid profiles and interactions among individual alkaloids.


Assuntos
Ração Animal/toxicidade , Alcaloides de Claviceps/toxicidade , Fezes/química , Ração Animal/análise , Animais , Dieta/veterinária , Grão Comestível/química , Alcaloides de Claviceps/análise , Hordeum/química , Masculino , Medicago sativa/química , Ovinos/crescimento & desenvolvimento
5.
Aust Health Rev ; 38(4): 396-400, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25000849

RESUMO

Care coordination models have developed in response to the recognition that Australia's health and welfare service system can be difficult to access, navigate and is often inefficient in caring for people with severe and persistent mental illness (SPMI) and complex care and support needs. This paper explores how the Australian Government's establishment of the Partners in Recovery (PIR) initiative provides an opportunity for the development of more effective and efficient models of coordinated care for the identified people with SPMI and their families and carers. In conceptualising how the impact of the PIR initiative could be maximised, the paper explores care coordination and what is known about current best practice. The key findings are the importance of having care coordinators who are well prepared for the role, can demonstrate competent practice and achieve better systemic responses focused on the needs of the client, thus addressing the barriers to effective care and treatment across complex service delivery systems.


Assuntos
Prestação Integrada de Cuidados de Saúde/organização & administração , Serviços de Saúde Mental/organização & administração , Austrália , Comportamento Cooperativo
6.
Patient Prefer Adherence ; 8: 63-72, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24470755

RESUMO

PURPOSE: Adolescents report high asthma-related morbidity that can be prevented by adequate self-management of the disease. Therefore, there is a need for a developmentally appropriate strategy to promote effective asthma self-management. Mobile phone-based technology is portable, commonly accessible, and well received by adolescents. The purpose of this study was to develop and evaluate the feasibility and acceptability of a comprehensive mobile phone-based asthma self-management aid for adolescents (mASMAA) that was designed to facilitate symptom monitoring, treatment adherence, and adolescent-parent partnership. The system used state-of-the-art natural language-understanding technology that allowed teens to use unconstrained English in their texts, and to self-initiate interactions with the system. MATERIALS AND METHODS: mASMAA was developed based on an existing natural dialogue system that supports broad coverage of everyday natural conversation in English. Fifteen adolescent-parent dyads participated in a 2-week trial that involved adolescents' daily scheduled and unscheduled interactions with mASMAA and parents responding to daily reports on adolescents' asthma condition automatically generated by mASMAA. Subsequently, four focus groups were conducted to systematically obtain user feedback on the system. Frequency data on the daily usage of mASMAA over the 2-week period were tabulated, and content analysis was conducted for focus group interview data. RESULTS: Response rates for daily text messages were 81%-97% in adolescents. The average number of self-initiated messages to mASMAA was 19 per adolescent. Symptoms were the most common topic of teen-initiated messages. Participants concurred that use of mASMAA improved awareness of symptoms and triggers, promoted treatment adherence and sense of control, and facilitated adolescent-parent partnerships. CONCLUSION: This study demonstrates the utility and user acceptability of mASMAA as a potential asthma self-management tool in a selective group of adolescents. Further research is needed to replicate the findings in a large group of adolescents from sociodemographically diverse backgrounds to validate the findings.

7.
Appl Spectrosc ; 67(11): 1343-7, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24160888

RESUMO

To evaluate nutrient digestibility, we propose the novel approach of functional group digestibility (FGD). The FGD was based on the absorbance of specific Fourier transform infrared (FT-IR) peaks and the ratio of an inorganic indigestible marker in diet and digesta, without calibration. For application, samples of diet and digesta of wheat with predetermined crude protein (CP) digestibility were scanned on an FT-IR spectrometer equipped with a single-reflection attenuated total reflection (ATR) attachment. The FGD in the amide I region (1689-1631 cm (-1)) of digesta spectra was strongly related (R(2) = 0.99) with CP digestibility. The measured diet CP digestibility ranged from 60.4 to 87.8% with a standard error of prediction of 1.09%. In conclusion, instead of predictions based on calibrations, FGD can be calculated directly from spectra, provided the ratio of marker in diet and undigested residue is known, and then accurately predicts nutrient digestibility.


Assuntos
Ração Animal/análise , Proteínas/química , Proteínas/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Amidas/análise , Amidas/química , Animais , Dieta , Digestão , Íleo/metabolismo , Modelos Lineares , Proteínas/análise , Suínos , Triticum/metabolismo
8.
Comput Linguist Assoc Comput Linguist ; 38(3): 469-478, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25838637

RESUMO

We describe a novel domain, Fruit Carts, aimed at eliciting human language production for the twin purposes of (a) dialogue system research and development and (b) psycholinguistic research. Fruit Carts contains five tasks: choosing a cart, placing it on a map, painting the cart, rotating the cart, and filling the cart with fruit. Fruit Carts has been used for research in psycholinguistics and in dialogue systems. Based on these experiences, we discuss how well the Fruit Carts domain meets four desired features: unscripted, context-constrained, controllable difficulty, and separability into semi-independent subdialogues. We describe the domain in sufficient detail to allow others to replicate it; researchers interested in using the corpora themselves are encouraged to contact the authors directly.

9.
J Biomed Inform ; 39(5): 500-13, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16545620

RESUMO

Dialogue systems for health communication hold out the promise of providing intelligent assistance to patients through natural interfaces that require no training to use. But in order to make the development of such systems cost effective, we must be able to use generic techniques and components which are then specialized as needed to the specific health problem and patient population. In this paper, we describe Chester, a prototype intelligent assistant that interacts with its user via conversational natural spoken language to provide them with information and advice regarding their prescribed medications. Chester builds on our prior experience constructing conversational assistants in other domains. The emphasis of this paper is on the portability of our generic spoken dialogue technology, and presents a case study of the application of these techniques to the development of a dialogue system for health communication.


Assuntos
Inteligência Artificial , Comunicação , Humanos , Sistemas Computadorizados de Registros Médicos , Educação de Pacientes como Assunto/métodos , Software
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