17 results on '"Muñoz, Camila"'
Search Results
2. Utilization of the Fungus Pycnoporus sp. for Remediation of a Sugarcane Industry Effluent.
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Farfán, Clara, Lozano, Verónica Laura, Borja, Claudia Nidia, Alvarez Dalinger, Florencia, Muñoz, Camila, and Moraña, Liliana
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Lignocellulosic fungi are highly versatile organisms with valuable applications in bioremediation processes, including the biodegradation of agro-industrial effluents. In this work, the use of a native strain of the white-rot fungus, Pycnoporus aff. sanguineus, in the bioremediation of the sugar industry waste called vinasse was studied, originating from the San Martín del Tabacal Sugar Mill, located in the north of the Salta province, Argentina. We studied, under controlled laboratory conditions, the bioremediation process of three concentrations of vinasse (5, 10, and 25% in distilled water) with a native isolated strain. The results showed biomass growth at all three tested concentrations, with a maximum at the highest vinasse concentration (25%), while the percentages of color and Chemical Oxygen Demand (COD) removal indicated that the most efficient treatment was with 10% vinasse. The results obtained are promising for the treatment of effluents from the sugar industry using white-rot fungi, considering the valuable subproducts of Pycnoporus spp. biomass. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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3. Effects of type of substrate and dilution rate on fermentation in serial rumen mixed cultures.
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Ungerfeld, Emilio M., Cancino-Padilla, Nathaly, Vera-Aguilera, Nelson, Scorcione, M. Carolina, Saldivia, Marcelo, Lagos-Pailla, Lorena, Vera, Milena, Cerda, Cristián, Muñoz, Camila, Urrutia, Natalie, and Martínez, Emilio D.
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FERMENTATION ,DILUTION ,NAD (Coenzyme) ,MICROBIAL growth ,PYRUVATES ,CONCENTRATE feeds ,ORGANIC compounds ,METHANOGENS - Abstract
Forages and concentrates have consistently distinct patterns of fermentation in the rumen, with forages producing more methane (CH4) per unit of digested organic matter (OM) and higher acetate to propionate ratio than concentrates. A mechanism based on the Monod function of microbial growth has been proposed to explain the distinct fermentation pattern of forages and concentrates, where greater dilution rates and lower pH associated with concentrate feeding increase dihydrogen (H
2 ) concentration through increasing methanogens growth rate and decreasing methanogens theoretically maximal growth rate, respectively. Increased H2 concentration would in turn inhibit H2 production, decreasing methanogenesis, inhibit H2 -producing pathways such as acetate production via pyruvate oxidative decarboxylation, and stimulate H2 -incorporating pathways such as propionate production. We examined the hypothesis that equalizing dilution rates in serial rumen cultures would result in a similar fermentation profile of a high forage and a high concentrate substrate. Under a 2×3 factorial arrangement, a high forage and a high concentrate substrate were incubated at dilution rates of 0.14, 0.28, or 0.56h-1 in eight transfers of serial rumen cultures. Each treatment was replicated thrice, and the experiment repeated in two different months. The high concentrate substrate accumulated considerably more H2 and formate and produced less CH4 than the high forage substrate. Methanogens were nearly washed-out with high concentrate and increased their initial numbers with high forage. The effect of dilution rate was minor in comparison to the effect of the type of substrate. Accumulation of H2 and formate with high concentrate inhibited acetate and probably H2 and formate production, and stimulated butyrate, rather than propionate, as an electron sink alternative to CH4 . All three dilution rates are considered high and selected for rapidly growing bacteria. The archaeal community composition varied widely and inconsistently. Lactate accumulated with both substrates, likely favored by microbial growth kinetics rather than by H2 accumulation thermodynamically stimulating electron disposal from NADH into pyruvate reduction. In this study, the type of substrate had a major effect on rumen fermentation largely independent of dilution rate and pH. [ABSTRACT FROM AUTHOR]- Published
- 2024
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4. Predictive model of the intention to practice physical activity in university students of pedagogy in Antofagasta (Chile).
- Author
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Luis de Cos, Gurutze, Urrutia-Gutierrez, Saioa, Retamal-Muñoz, Camila, Troncoso-Ulloa, Karen, and González-Valencia, Cynthia
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PHYSICAL activity ,COLLEGE students ,MEDICAL personnel ,PREDICTION models ,REGRESSION analysis ,SEDENTARY behavior ,PHYSICAL fitness ,SPORTS participation - Abstract
Copyright of Retos: Nuevas Perspectivas de Educación Física, Deporte y Recreación is the property of Federacion Espanola de Asociaciones de Docentes de Educacion Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2023
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5. Seaweeds in Food: Current Trends.
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Rogel-Castillo, Cristian, Latorre-Castañeda, Monica, Muñoz-Muñoz, Camila, and Agurto-Muñoz, Cristian
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MARINE algae as food ,ANIMAL health ,HEAVY metals ,NEW product development ,BIOACTIVE compounds ,LAMINARIA ,MARINE algae - Abstract
Edible seaweeds are an excellent source of macronutrients, micronutrients, and bioactive compounds, and they can be consumed raw or used as ingredients in food products. However, seaweeds may also bioaccumulate potentially hazardous compounds for human health and animals, namely, heavy metals. Hence, the purpose of this review is to analyze the recent trends of edible seaweeds research: (i) nutritional composition and bioactive compounds, (ii) the use and acceptability of seaweeds in foodstuffs, (iii) the bioaccumulation of heavy metals and microbial pathogens, and (iv) current trends in Chile for using seaweeds in food. In summary, while it is evident that seaweeds are consumed widely worldwide, more research is needed to characterize new types of edible seaweeds as well as their use as ingredients in the development of new food products. Additionally, more research is needed to maintain control of the presence of heavy metals to assure a safe product for consumers. Finally, the need to keep promoting the benefits of seaweed consumption is emphasized, adding value in the algae-based production chain, and promoting a social algal culture. [ABSTRACT FROM AUTHOR]
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- 2023
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6. Expression of Macrophage Polarization Markers against the Most Prevalent Serotypes of Aggregatibacter actinomycetemomitans.
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Betancur, Daniel, Muñoz, Camila, and Oñate, Angel
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MACROPHAGES ,ACTINOBACILLUS actinomycetemcomitans ,SEROTYPES ,GRAM-negative bacteria ,CHEMOKINES ,CD14 antigen ,CD4 antigen - Abstract
Aggregatibacter actinomycetemcomitans, a Gram-negative bacterium with seven serotypes (a–g) according to the structure of its LPS, has been defined as one of the most important pathogens in the development of a dysbiotic periodontal biofilm and the onset of periodontitis (an inflammatory chronic disease of the tissues around the teeth), where the serotype b is characterized as the most virulent compared with the other serotypes. The aim of this study was to evaluate the expression of the macrophage polarization markers M0, M1, and M2 against A. actinomycetemcomitans. Methods: THP-1 cells were infected with A. actinomycetemcomitans serotypes a, b, and c. The expression of CD11b, CD4, CD14, and CD68 for M0; IL-6, HLA/DRA, and CXCL10 for M21, and IL-10, CD163, fibronectin-1 or FN1, and CCL17 was evaluated by qPCR at 2 and 24 h after infection. Results: An increase in the expression of these molecules was induced by all serotypes at both times of infection, showing higher levels of expression to the M1 panel at 2 and 24 h compared to other markers. Conclusions: A. actinomycetemcomitans has a role in the macrophage polarization to the M1 phenotype in a non-serotype-dependent manner. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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7. Feeding Strategies to Mitigate Enteric Methane Emission from Ruminants in Grassland Systems.
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Vargas, Juan, Ungerfeld, Emilio, Muñoz, Camila, and DiLorenzo, Nicolas
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RANGE management ,GREENHOUSE gas mitigation ,SILVOPASTORAL systems ,RUMINANTS ,GRASSLANDS ,FEEDING tubes - Abstract
Simple Summary: Ruminants under grazing conditions play an important role, especially in developing countries. Enteric methane emissions from ruminants are greater with pasture-based diets; however, it is not clear which abatement practices are effective to reduce methane emissions under grazing conditions. The objective of this review was to identify and describe enteric methane abatement practices for ruminants that are applicable under grazing conditions. Decreasing the pre-grazing herbage mass reduced methane emissions per unit of product. Other grazing management practices such as increased stocking rate, decreased forage maturity, rotational stocking, and incorporating tannin-containing or non-tannin-containing legumes showed inconsistent results. Nitrogen fertilization or silvopastoral systems did not modify methane emissions, although they may alter carbon sequestration in a system. Supplementation in grazing conditions shows inconsistent responses on methane emissions. However, lipid supplementation showed promising results. Identifying and implementing grazing strategies and supplementation practices under grazing conditions is required to increase efficiency and reduce the environmental impact of these systems. Ruminants produce approximately 30% of total anthropogenic methane emissions globally. The objective of this manuscript was to review nutritional enteric methane abatement practices for ruminants that are applicable under grazing conditions. A total of 1548 peer-reviewed research articles related to the abatement of enteric methane emissions were retrieved and classified into four categories: non-experimental, in vitro, in vivo confined, and in vivo grazing. The methane abatement strategies for grazing systems were arranged into grazing management and supplementation practices. Only 9% of the retrieved papers have been conducted under grazing conditions. Eight grazing management practices have been evaluated to reduce methane emissions. Decreasing the pre-grazing herbage mass reduced the methane emission per unit of product. Other grazing management practices such as increased stocking rate, decreased forage maturity, rotational stocking, and incorporating tannin-containing or non-tannin-containing feeds showed contradictory results. Nitrogen fertilization or silvopastoral systems did not modify methane emissions. Conversely, supplementation practices in grazing conditions showed contradictory responses on methane emissions. Lipid supplementation showed promising results and suggests applicability under grazing conditions. Identifying and implementing grazing strategies and supplementation practices under grazing conditions is required to increase efficiency and reduce the environmental impact of these systems. [ABSTRACT FROM AUTHOR]
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- 2022
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8. Assessment protocol and reference values of vestibulo-ocular reflex (VOR) gain in the horizontal plane recorded with video-Head Impulse Test (vHIT) in a pediatric population.
- Author
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Rivera Retamal, Sebastián, Oyarzún Díaz, Patricia, Marcotti Fernández, Anthony, Gallardo Muñoz, Camila, Espinoza, Melissa Richard, Sepúlveda Araya, Valeria, and Tapia Rivera, Javiera
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- 2021
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9. Academically Oriented Activity Breaks for First-Grade Chilean Students: Development and Pilot Testing Effectiveness.
- Author
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Kain, Juliana, Ortega, Alejandra, Garmendia, María Luisa, Corvalán, Camila, Marambio, Paola, Rojas, Joanna, Muñoz, Camila, and Leyton, Barbara
- Abstract
We developed and pilot tested the effectiveness of a physically active academic program, Active Breaks (AB), whose objective is to increase school time moderate/vigorous physical activity (MVPA) among first graders, through daily 15-minute bouts of MVPA, at the beginning of the first lesson. Initially, 240 cards including one game each were developed and tested in first-grade students from 16 schools in Santiago. Trained observers and school teachers assessed the time, ease, and feasibility of implementation for each card. Barriers and facilitators to implementation were obtained from semistructured interviews to 14 teachers (out of 16). In eight schools (n = 556 students), we compared school time MVPA (with accelerometers) at baseline and follow-up, using test of proportions. One-hundred and twenty cards (games) complied with all aspects. AB were implemented 50% of the time with a duration of 14 minutes (SD = 5). More than 90% of the time, teachers felt competent to conduct AB, and children understood the instructions and enjoyed the activity. The main facilitators included teachers liking physical activity and considering it important, support of principal and school staff, and conducting AB inside the classroom. Barriers included teacher's workload and having to conduct AB during the first lesson. During the 4-month period of implementation, MVPA increased by 1.5 and 1.2 percentage points in boys and girls, respectively. The set of 120 cards is easy and feasible to implement. Moreover, preliminary results suggest they could be effective in increasing MVPA during school time, although studies with longer follow-ups are needed to assess the validity of these findings. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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10. Antimicrobial Activity of Piper marginatum Jacq and Ilex guayusa Loes on Microorganisms Associated with Periodontal Disease.
- Author
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Gamboa, Fredy, Muñoz, Camila-Cristina, Numpaque, Gloria, Sequeda-Castañeda, Luis Gonzalo, Gutierrez, Sandra Janeth, and Tellez, Nohemi
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ANTI-infective agents ,PERIODONTAL disease ,COMMUNICABLE diseases ,PORPHYROMONAS gingivalis ,FUSOBACTERIUM - Abstract
Background. Chronic periodontitis is a multifactorial infectious disease, where multiple bacteria, such as Porphyromonas gingivalis, Prevotella intermedia, and Fusobacterium nucleatum are implicated. The main purpose of researching natural products is to find substances or compounds with antimicrobial activity. Aim. The objective of this work was to determine antimicrobial activity from extracts and obtained fractions from Piper marginatum Jacq and Ilex guayusa Loes on P. gingivalis ATCC 33277, F. nucleatum ATCC 25586, and P. intermedia ATCC 25611. Methods. Total ethanol extracts were obtained from both plants. Fractions were obtained from total ethanol extracts with amberlite as a stationary phase employing hexane, acetone, and ethanol-water as solvents. Qualitative and quantitative phytochemical characterization was performed on total ethanol extracts from both plants. Antimicrobial activity from total ethanol extracts and fractions from both plants were evaluated on P. gingivalis ATCC 33277, F. nucleatum ATCC 25586, and P. intermedia ATCC by the well diffusion method with Wilkins–Chalgren agar. Results. Piper marginatum Jacq total ethanol extract presented antimicrobial activity against all three bacteria, whereas Ilex guayusa Loes was only efficient against P. gingivalis ATCC 33277 and P. intermedia ATCC 25611, with inhibition halos from 9.3 to 30 mm. Ilex guayusa Loes obtained fractions presented antimicrobial activity against all three microorganisms evaluated, with inhibition halos ranging from 9.7 to 18.7 mm. In regards to Piper marginatum Jacq fractions, inhibition halos were between 8.3 and 19 mm, against all three microorganisms evaluated; only hexane fraction did not present antimicrobial activity against F. nucleatum ATCC 25586. Conclusion. Piper marginatum Jacq and Ilex guayusa Loes total ethanol extracts and fractions presented outstanding antimicrobial activity against P. gingivalis ATCC 33277, P. intermedia ATCC 25611, and F. nucleatum ATCC 25586. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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11. Análisis bibliométrico de la educación en ingeniería desde el año 2007 a 2017.
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De León-Camero, Mateo J., Solórzano-Muñoz, Camila, and Valencia, Guillermo E.
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- 2018
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12. How does descending aorta geometry change when it dissects?
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Rylski, Bartosz, Muñoz, Camila, Beyersdorf, Friedhelm, Siepe, Matthias, Reser, Diana, Carrel, Thierry, Schoenhoff, Florian, Schlensak, Christian, Lescan, Mario, and Eckstein, Hans-Henning
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AORTA ,AORTIC dissection ,TERTIARY care ,AORTA surgery ,SURGICAL stents ,ANATOMY - Abstract
OBJECTIVES: Thoracic endovascular aortic repair is the treatment of choice in complicated acute type B aortic dissection. How to infer predissection aortic diameter is not well understood. Our aim was to delineate changes in descending aortic geometry due to dissection. METHODS: Five tertiary centres reviewed their acute aortic dissection type B databases containing 802 patients. All patients who had undergone computed tomography angiography less than 2 years before and immediately after aortic dissection onset were included. We compared the aortic geometry before and after the dissection onset. RESULTS: Altogether 25 patients were included [median age 60 (first quartile 52, third quartile 72) years; 60% men]. In all except 1 patient, the maximum descending aortic diameter was less than 45mm before aortic dissection onset. The largest increase in diameter induced by the dissection was observed in the proximal descending aorta 28.2 (25.1, 32.1) vs 34.6 (31.3, 39.1)mm (+6.4 mm; +23%; P < 0.001). The thoracic descending aortic length increased after the dissection onset [253.3 (229.3, 271.9) vs 261.3 (247.9, 285.4) mm; P = 0.003]. The predissection aortic diameter of the proximal thoracic descending aorta was 7.9 (5.2, 10.7)mm larger (P < 0.001) than the post-dissection area-derived true-lumen diameter and 2.5 (1.3, 6.1)mm larger than the maximum true-lumen diameter (P < 0.001). CONCLUSIONS: Type B aortic dissection increases the diameter, length and volume of the descending thoracic aorta. The predissection aortic diameter most closely resembles the post-dissection maximum diameter of the true lumen. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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13. In Situ Visualization of the Local Photothermal Effect Produced on α-Cyclodextrin Inclusion Compound Associated with Gold Nanoparticles.
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Silva, Nataly, Muñoz, Camila, Diaz-Marcos, Jordi, Samitier, Josep, Yutronic, Nicolás, Kogan, Marcelo J, and Jara, Paul
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GOLD nanoparticles ,PHOTOTHERMAL effect ,VISUALIZATION ,CYCLODEXTRINS ,ATOMIC force microscopy ,MATRIX-assisted laser desorption-ionization - Abstract
Evidence of guest migration in α-cyclodextrin-octylamine (α-CD-OA) inclusion compound (IC) generated via plasmonic heating of gold nanoparticles (AuNPs) has been studied. In this report, we demonstrate local effects generated by laser-mediated irradiation of a sample of AuNPs covered with inclusion compounds on surface-derivatized glass under liquid conditions by atomic force microscopy (AFM). Functionalized AuNPs on the glass and covered by the ICs were monitored by recording images by AFM during 5 h of irradiation, and images showed that after irradiation, a drastic decrease in the height of the AuNPs occurred. The absorption spectrum of the irradiated sample showed a hypsochromic shift from 542 to 536 nm, evidence suggesting that much of the population of nanoparticles lost all of the parts of the overlay of ICs due to the plasmonic heat generated by the irradiation. Mass spectrometry matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF) performed on a sample containing a collection of drops obtained from the surface of the functionalized glass provided evidence that the irradiation lead to disintegration of the ICs and therefore exit of the octylamine molecule (the guest) from the cyclodextrin cavity (the matrix). [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]
- Published
- 2016
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14. Quantization error in magnetic resonance imaging.
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Cadiz, Rodrigo F., Muñoz, Camila, Tejos, Cristian, Andia, Marcelo E., Uribe, Sergio, and Irarrazaval, Pablo
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MAGNETIC resonance imaging ,SIGNAL quantization ,ERROR probability ,DIAGNOSTIC imaging research ,NUCLEAR magnetic resonance - Abstract
ABSTRACT Due to the special nature of the acquisition domain, the quantization process of magnetic resonance imaging (MRI) data presents challenges that are not present in other medical imaging techniques. In this article, we demonstrate that the quantization error in MRI cannot be assumed to be a random variable with uniform distribution across the entire acquisition domain. Furthermore, the introduced error is not statistically independent of the input signal. On the contrary, we show that this error is correlated with the object that is being scanned, producing perceptually unpleasant artifacts in the image domain. Although the quantization error is not generally a critical issue in two-dimensional (2D) MRI acquisition, it could be in the case of 3D acquisitions and in noise estimation measurements. © 2014 Wiley Periodicals, Inc. Concepts Magn Reson Part A 43A: 79-89, 2014. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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15. Long-Term and Carryover Effects of Supplementation with Whole Oilseeds on Methane Emission, Milk Production and Milk Fatty Acid Profile of Grazing Dairy Cows.
- Author
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Muñoz, Camila, Villalobos, Rodrigo, Peralta, Alejandra María Teresa, Morales, Rodrigo, Urrutia, Natalie Louise, and Ungerfeld, Emilio Mauricio
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MILKFAT ,DAIRY cattle ,MILK yield ,GRAZING ,FATTY acids ,MILK proteins - Abstract
Simple Summary: Dairy cow diets that include oils have shown potential to decrease methane emissions, which contribute to climate change. However, there is limited information on long-term interventions for animals in grazing systems. The aim of this study was to evaluate the effects of feeding oilseeds on the persistency of methane mitigation effects and milk production of dairy cows during a spring and summer grazing season. Carryover effects into autumn were studied. Eight weeks after beginning the feeding trial, cottonseed was more effective than linseed or rapeseed in decreasing methane per kilogram of ingested feed, but the mitigation effect did not persist when evaluated 11 weeks later. All oilseeds maintained milk production in spring, but in summer, milk yield was lower with cottonseed. There were no carryover effects of feeding oilseeds, once supplementation ended. Thus, adding oils to dairy cow diets through cottonseed supplementation had only a temporary effect on methane mitigation. This long-term study, conducted under grazing conditions, can help to assess how proposed interventions to mitigate methane can affect production and sustainability aspects of grazing dairy systems. Research is ongoing to find nutritional methane (CH
4 ) mitigation strategies with persistent effects that can be applied to grazing ruminants. Lipid addition to dairy cow diets has shown potential as means to decrease CH4 emissions. This study evaluated the effects of oilseeds on CH4 emission and production performance of grazing lactating dairy cows. Sixty Holstein Friesian cows grazing pasture were randomly allocated to 1 of 4 treatments (n = 15): supplemented with concentrate without oilseeds (CON), with whole cottonseed (CTS), rapeseed (RPS) or linseed (LNS). Oilseeds were supplemented during weeks 1–16 (spring period) and 17–22 (summer period), and the autumn period (wk 23–27) was used to evaluate treatment carryover effects. Cows fed CTS decreased CH4 yield by 14% compared to CON in spring, but these effects did not persist after 19 weeks of supplementation (summer). Compared to CON, RPS decreased milk yield and CTS increased milk fat concentration in both spring and summer. In summer, CTS also increased milk protein concentration but decreased milk yield, compared to CON. In spring, compared to CON, CTS decreased most milk medium-chain fatty acids (FA; 8:0, 12:0, 14:0 and 15:0) and increased stearic, linoleic and rumenic FA, and LNS increased CLA FA. There were no carry-over effects into the autumn period. In conclusion, supplementation of grazing dairy cows with whole oilseeds resulted in mild effects on methane emissions and animal performance. In particular, supplementing with CTS can decrease CH4 yield without affecting milk production, albeit with a mild and transient CH4 decrease effect. Long term studies conducted under grazing conditions are important to provide a comprehensive overview of how proposed nutritional CH4 mitigation strategies affect productivity, sustainability and consumer health aspects. [ABSTRACT FROM AUTHOR]- Published
- 2021
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16. Seasonal Effect on Feed Intake and Methane Emissions of Cow–Calf Systems on Native Grassland with Variable Herbage Allowance.
- Author
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Orcasberro, M. Soledad, Loza, Cecilia, Gere, José, Soca, Pablo, Picasso, Valentín, Astigarraga, Laura, Carro, Maria Dolores, Jonker, Arjan, Pinares-Patiño, César S., and Muñoz, Camila
- Subjects
COW-calf system ,RANGE management ,CATTLE weight ,METHANE ,GRASSES - Abstract
Simple Summary: Improving grazing management provides the opportunity of limiting methane emissions from beef cattle systems, and consequently offers economic along with environmental benefits. The aim of this study was to measure methane emissions and herbage intake, in order to estimate the methane yield from beef cows grazing on native grasslands at different herbage allowances. The trial, that it is part of a long-term experiment, consisted in two treatments of herbage allowance, with forty pregnant heifers. Methane emissions and intake were estimated for three 17-day periods during autumn, winter and spring. Methane emissions and organic matter intake did not differ between herbage allowance treatments, which resulted in similar methane yield. However, all variables were significantly affected by the period, with a marked increase in spring, except for methane yield expressed as a proportion of Gross Energy intake. Results show that methane emissions and intake were significantly affected by the season of the year, but not by the level of herbage allowance used in this study. These are the first data obtained on methane emissions in pregnant heifers in native grassland for Uruguay. The aim of this study was to measure methane emissions (CH
4 ) and herbage intake, and, on the basis of these results, obtain the methane yield (MY, methane yield as g CH4 /kg dry matter intake (DMI) and Ym, methane yield as a percentage of Gross Energy intake), from beef cows grazing on native grasslands. We used forty pregnant heifers, with two treatments of herbage allowance (HA) adjusted seasonally (8 and 5 kg dry matter (DM)/kg cattle live weight (LW), on average), during autumn, winter and spring. Methane emissions (207 g CH4 /d), organic matter intake (OMI, 7.7 kg organic matter (OM)/d), MY (23.6 g CH4 /kg DMI) and Ym (7.4%), were similar between treatments. On the other hand, all variables had a marked increase in spring (10.8 kg OM/d and 312 g CH4 /d), except for Ym. The methane emission factor from Intergovernmental Panel on Climate Change (IPCC) Tier 2 estimated with these results was 78 kg CH4 /head/year. The results show that methane emissions and intake were influenced by the season, but not by the HA analyzed in this study. This information for cow–calf systems in native grasslands in Uruguay can be used in National greenhouse gases (GHG) inventories, representing a relevant contribution to global GHG inventories. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
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17. Inhibiting Methanogenesis Stimulated de novo Synthesis of Microbial Amino Acids in Mixed Rumen Batch Cultures Growing on Starch but not on Cellulose.
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Ungerfeld, Emilio M., Aedo, M. Fernanda, Muñoz, Camila, Urrutia, Natalie L., Martínez, Emilio D., and Saldivia, Marcelo
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AMINO acid synthesis ,BUTYRATES ,CELLULOSE ,STARCH ,MICROBIOLOGICAL synthesis ,PLANT proteins - Abstract
Ameliorating methane (CH
4 ) emissions from ruminants would have environmental benefits, but it is necessary to redirect metabolic hydrogen ([H]) toward useful sinks to also benefit animal productivity. We hypothesized that inhibiting rumen methanogenesis would increase de novo synthesis of microbial amino acids (AA) as an alternative [H] sink if sufficient energy and carbon are provided. We examined the effects of inhibiting methanogenesis with 9, 10-anthraquione (AQ) on mixed rumen batch cultures growing on cellulose or starch as sources of energy and carbon contrasting in fermentability, with ammonium (NH4 + ) or trypticase (Try) as nitrogen (N) sources. Inhibiting methanogenesis with AQ inhibited digestion with cellulose but not with starch, and decreased propionate and increased butyrate molar percentages with both substrates. Inhibiting methanogenesis with 9, 10-anthraquinone increased de novo synthesis of microbial AA with starch but not with cellulose. The decrease in the recovery of [H] caused by the inhibition of methanogenesis was more moderate with starch due to an enhancement of butyrate and AA as [H] sinks. There may be an opportunity to simultaneously decrease the emissions of CH4 and N with some ruminant diets and replace plant protein supplements with less expensive non-protein nitrogen sources such as urea. [ABSTRACT FROM AUTHOR]- Published
- 2020
- Full Text
- View/download PDF
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