Tropical Grasslands-Forrajes Tropicales最新文献

{"title":"Dinámica de tallos e índice de estabilidad en cinco cultivares de Urochloa en condiciones semiáridas","authors":"Fernando Lucio Ruiz, Santiago Joaquin Cancino, Jonathan Rául Garay Martínez, Yuridia Bautista Martínez, Benigno Estrada Drouaillet, Andrés Gilberto Limas Martínez","doi":"10.17138/tgft(11)1-10","DOIUrl":"https://doi.org/10.17138/tgft(11)1-10","url":null,"abstract":"El objetivo de esta investigación fue evaluar los efectos de la temperatura y precipitación sobre la dinámica de tallos y el índice de estabilidad en cinco cultivares del género Urochloa en condiciones semiáridas. Los cultivares evaluados fueron Camello I, Camello II, Mulato II, Convert 330 y Cobra, en un diseño completamente al azar con seis repeticiones. La temperatura y precipitación presentes durante el periodo de evaluación estimularon el comportamiento de la dinámica de tallos (P<0.05). Los cultivares Cobra y Mulato II presentaron las mayores densidades de tallos (> 4,000 tallos/m2 en promedio), como respuesta al mayor número de hijuelos (769 y 718/m2, respectivamente), aún con una mortalidad de tallos relativamente alta (336 y 449 tallos/m2, respectivamente). El tener los valores máximos de unidades calor acumulados en períodos con poca o nula precipitación, comprometió el índice de estabilidad de la pradera (con valores menores a 1). El corte en el periodo de heladas (noviembre) provocó el incremento del 20 % en la tasa de mortalidad y, por consiguiente, una disminución en el índice de estabilidad de hasta 0.83. Las condiciones ambientales y el crecimiento ininterrumpido en los cultivares de Urochloa, provoca la pérdida en la estabilidad de la pradera, debido a la menor tasa de ahijamiento con respecto a la tasa de mortalidad de tallos.","PeriodicalId":56049,"journal":{"name":"Tropical Grasslands-Forrajes Tropicales","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43980085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of grazing intensity and pasture type on soil organic carbon stock in the semi-arid tropics of India","authors":"Sunil Kumar, A. Dixit, M. Prasad, S. Rai, S. K. Mahanta, Sultan Singh, S. Radotra, P. K. Ghosh","doi":"10.17138/tgft(11)41-51","DOIUrl":"https://doi.org/10.17138/tgft(11)41-51","url":null,"abstract":"Pastures may act as carbon sources and sinks depending on grazing pressure and management practices. Soil organic carbon (SOC) stock and its fractions were quantified under 3 different grazing intensities using 5, 10 and 15 sheep/ha under sown, improved and natural pastures in the semi-arid tropics of India. Results revealed that after 3 years, improved pasture had significantly higher particulate organic carbon (POC ~4.5 g/kg), SOC (~0.53 %), total organic carbon (TOC~7 g/kg) and SOC stock (~15 mg/ha) as compared with sown and natural pastures. Labile carbon (LC ~185 mg/kg) and soil microbial biomass carbon (SMBC ~378 µg/g soil) were higher under natural pasture. A moderate grazing intensity of 10 sheep/ha resulted in significantly greater carbon fractions, TOC and SOC stock. SOC stock and its fractions were significantly higher in the topsoil layers as compared with the subsoil layers. These results indicate that improved pasture management practices with moderate grazing intensity can be recommended for improving SOC stock and its fractions in semi-arid tropical pastures.","PeriodicalId":56049,"journal":{"name":"Tropical Grasslands-Forrajes Tropicales","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44536273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estimación de la oferta de forraje y la calidad nutricional del pasto Urochloa humidicola cv Llanero partir de imágenes multiespectrales.","authors":"Raúl Alejandro Díaz Giraldo, Mauricio Álvarez de León, Álvaro Rincón Castillo, Otoniel Pérez López, Edgar Cárdenas Rocha, William Posada Asprilla","doi":"10.17138/tgft(11)61-74","DOIUrl":"https://doi.org/10.17138/tgft(11)61-74","url":null,"abstract":"El uso de imágenes multiespectrales en la evaluación de pasturas se ha convertido en una herramienta práctica para la gestión de los sistemas pastoriles a nivel predial, ya que estas permiten construir índices de vegetación (IV) los cuales se relacionan con diferentes características productivas y fisiológicas de las plantas. El objetivo de este estudio fue estimar la oferta de forraje y la calidad nutricional de una pastura de Urochloa humidicola cv Llanero a partir de IV. La oferta de forraje (OF) y la altura de planta (ALP) fueron evaluadas en campo a los 28 días de rebrote, tomando muestras para análisis espectro radiométrico y para determinar los contenidos de proteína cruda (PC), fibra detergente neutro (FDN), fibra detergente ácido (FDA) y lignina (LIG). Los vuelos se realizaron a 70 metros de altura y se evaluaron siete IV (NDVI, GCI, SRPI, SR, GNDVI, SAVI y RDVI). El análisis de los datos se realizó por medio de componentes principales (CP) y modelos aditivos generalizados (GAM). Las variables que más contribuyeron a la formación del CP1 fueron las asociadas a la calidad nutricional del pasto y para el CP2 se agruparon las variables asociadas a la disponibilidad de forraje. El índice que mejor se relacionó con la OF fue el NDVI, con un efecto significativo por parte de la ALP (p≤0.001) y para la PC con el GNDVI. Los resultados para FND, FDA y LIG, presentaron un R2 bajo.","PeriodicalId":56049,"journal":{"name":"Tropical Grasslands-Forrajes Tropicales","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45761214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fermentation losses and aerobic stability of elephant grass silages containing Parkia platycephala pod meal and urea","authors":"Luana Andrade da Costa, R. Edvan, L. Bezerra, D. L. D. S. Jácome, José Pires De Carvalho Neto, Alex Rodrigues De Sousa, Mayra Fernanda Alves De Macedo, O. T. Medeiros, T. P. Dias-Silva, M. D. de Araújo","doi":"10.17138/tgft(11)52-60","DOIUrl":"https://doi.org/10.17138/tgft(11)52-60","url":null,"abstract":"Fermentation losses and aerobic stability of elephant grass silages with inclusion of 4 levels of Parkia platycephala pod meal (PP) (0, 10, 20 and 30 %) and 2 levels of urea (0 and 1.5 %) on as-fed basis were evaluated. The silages were analyzed for gas and effluent losses, dry matter recovery (DMR), pH and aerobic stability (pH and temperature) to determine effects of interactions between levels of urea and PP on gas losses, dry matter recovery, temperature and pH of the silages. The combination of urea and PP increased gas losses and reduced the DMR. PP reduced effluent losses and urea increased aerobic stability of the silages. pH values decreased with inclusion of PP and increased with use of urea. Silages containing 20 and 30 % PP showed greater stability over time, especially when associated with urea. PP with urea were effective in reducing effluent losses, maintaining DMR and allowing higher aerobic stability, with stability rupture from 40 h with the inclusion of 20 % of PP in elephant grass silages.","PeriodicalId":56049,"journal":{"name":"Tropical Grasslands-Forrajes Tropicales","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48060567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ingestive behavior and dry matter intake of dairy cattle grazing Kikuyu grass (Cenchrus clandestinus) pastures","authors":"Yesid Avellaneda-Avellaneda, Edgar Mancipe-Muñoz, J. Vargas-Martínez","doi":"10.17138/tgft(10)261-270","DOIUrl":"https://doi.org/10.17138/tgft(10)261-270","url":null,"abstract":"The objective of this study was to evaluate the effect of animal characteristics, grazing management, and supplementation on ingestive behavior and dry matter intake (DMI) of Kikuyu grass in lactating cows. Four trials were conducted with multiparous Holstein dairy cows in non-limiting forage conditions using 9 cows in each trial, 1 cow per paddock. Individual DMI was estimated through forage mass difference (pre- and post-grazing mass), ingestive behavior, and using markers [chromium oxide and undegradable acid detergent fibre (uADF)]. DMI was also estimated using 3 nutritional models (CSIRO, NRC, and AFRC). Grazing time and bite mass were positively related to the cow body weight, while bite rate showed a negative relationship with forage mass. The grazing time on a pasture of 42 d regrowth was less than the time spent grazing on a pasture of 28 or 56 d regrowth. DMI estimated by forage mass difference showed a positive relation with forage mass, supplement intake, and liveweight. DMI estimated using markers showed a positive relation with milk production and liveweight and a negative relationship with forage height. Forage mass difference and ingestive behavior measurements provided good estimates (R²>0.8) of DMI associated with forage mass, liveweight, and supplement intake in cows grazing Kikuyu grass.","PeriodicalId":56049,"journal":{"name":"Tropical Grasslands-Forrajes Tropicales","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43952850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The influence of seed structures on dormancy in seeds of Urochloa hybrid cultivar ‘Mulato Ⅱ’","authors":"Jinhai Liu, He-Chun Wang, Fucheng Luo, Y. Wang, Cui Xu, Jinjuan Jiang","doi":"10.17138/tgft(10)156-163","DOIUrl":"https://doi.org/10.17138/tgft(10)156-163","url":null,"abstract":"This study determined the effects of seed structures on seed dormancy and tested methods to break dormancy in seeds of Urochloa hybrid cultivar ‘Mulato II’. Seeds stored for 10 months in indoor ambient conditions were studied to determine effects of seed structures on seed germination and their water permeability. Results showed that seed structures presented a barrier to water permeability. Removal of lemmas, puncturing the seed coat, seed structure removal and sulfuric acid immersion all reduced seed dormancy. Water and alcohol extracts from different parts of seeds inhibited seed germination of Brassica pekinensis seeds. There were 3 mechanisms responsible for seed dormancy; first, the mechanical barrier of seed structures, which excluded water and reduced gas exchange as well as restricting growth of the embryo; second, an endogenous germination inhibitor mainly found in lemmas; and third, water permeability of the seed coat (including pericarp and testa). The mechanical removal of lemmas and immersion in concentrated sulfuric acid reduced seed dormancy, although mechanical removal of the lemma alone was effective, convenient and safer.","PeriodicalId":56049,"journal":{"name":"Tropical Grasslands-Forrajes Tropicales","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42978146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seasonal nutritive value and in vitro fermentation kinetics of foliage of some multipurpose shrub species in northeastern Mexico","authors":"Miguel Chávez Espinoza, H. Bernal Barragán, Maribel Guerrero Cervantes, I. Cantú Silva, Mauricio Cotera Correa, H. González Rodríguez, Andrés Eduardo Estrada Castillón","doi":"10.17138/tgft(10)184-194","DOIUrl":"https://doi.org/10.17138/tgft(10)184-194","url":null,"abstract":"This study aimed to determine seasonal chemical composition, metabolizable energy (ME) concentration, in vitro gas production patterns, in vitro organic matter digestibility (IVOMD) and in vitro true organic matter digestibility (IVTOMD) of foliage from 5 native shrub species (Celtis pallida, Croton suaveolens, Forestiera angustifolia, Guaiacum angustifolium and Parkinsonia aculeata) growing in semi-arid areas of northeastern Mexico between July 2018 and June 2019 at 2 research sites. Crude protein (CP) concentrations (>13.2% DM) found in leaf material should meet or exceed the requirements for maintenance of small ruminants; C. pallida provided the highest CP% (20.8‒29.3%). While CP% varied with season and site, species had a greater effect than either of those factors overall. ME concentrations ranged between 1.2 and 2.0 Mcal/kg DM. Neutral detergent fiber and acid detergent fiber concentrations ranged from 29.8 to 51.7% DM and 9.8 to 33.0% DM, respectively. Data obtained for IVOMD (34.5‒58.8%) and IVTOMD (64.1‒88.7%) demonstrate the high nutritive potential of leaf of browse species under study, especially C. pallida, as useful feed supplements for small ruminants in the semi-arid region of northeastern Mexico. Further studies could examine DM yields of browse from the various species, acceptance by small ruminants and their sustainability under regular defoliation under grazing.","PeriodicalId":56049,"journal":{"name":"Tropical Grasslands-Forrajes Tropicales","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49217071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The impact of COVID-19 on the sustainable intensification of forage-based beef and dairy value chains in Colombia: a blessing and a curse","authors":"S. Burkart, Manuel Díaz, Karen Enciso, Andrés Charry, Natalia Triana, M. Mena, José Luis Urrea-Benítez, Irieleth Gallo Caro, R. Van der Hoek","doi":"10.17138/tgft(10)237-248","DOIUrl":"https://doi.org/10.17138/tgft(10)237-248","url":null,"abstract":"The COVID-19 pandemic has exacerbated the difficulties associated with the need to transition the cattle sector in Latin America towards achieving sustainability and created a “double crisis” of pandemic and climate change. The increasing demand for animal sourced foods and the need to address the negative environmental impacts of cattle production, including greenhouse gas emissions, biodiversity loss and deforestation, and the implications of climate change on cattle production (prolonged droughts, prolonged rainy seasons, heat stress), have placed strong emphasis on sustainable intensification of forage-based beef and dairy systems for climate change mitigation and adaptation. This is needed to meet the commitments made by many Latin American countries to reduce greenhouse gas emissions under the Paris Agreement. Through a qualitative approach, this perspective paper reviews the present and potential impacts of the COVID-19 pandemic on progress towards sustainable intensification of the Colombian cattle sector. It also outlines new opportunities for sustainable intensification in Colombia that may provide useful examples for other Latin American countries. Short-term impacts such as: (i) increased input prices, (ii) limited access to inputs, credit, and technical assistance, and (iii) reduced incomes, have limited investment in sustainable intensification along the value chains. Reduced resources for research and development funding, unavailability of skilled and experienced staff, restrictions to travel and person-to-person interactions, in tandem, have caused setbacks in the development and application of sustainable technologies and programs. This has been addressed by increased use of technology for communication but there are difficulties with the broad availability of such technologies, especially farmers. A long-term shift of consumer demand towards more sustainable animal products is occurring and expected to continue, and this should lead to new opportunities for sustainable intensification.","PeriodicalId":56049,"journal":{"name":"Tropical Grasslands-Forrajes Tropicales","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43327648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Forage characterization of Carajás grass (Cenchrus purpureus × C. americanus) fertilized with a range of doses of protected urea under irrigation during the growing season","authors":"F. G. D. S. Alves, M. S. D. S. Carneiro, Marcos Jacome Araújo, R. Ratke, Bárbara Silveira Leandro de Lima, N. S. Gomes, R. F. Silva, R. Edvan","doi":"10.17138/tgft(10)164-171","DOIUrl":"https://doi.org/10.17138/tgft(10)164-171","url":null,"abstract":"The objective of this study was to assess the agronomic and nutritional responses of Carajás grass (Cenchrus purpureus × C. americanus, syn. Pennisetum purpureum × P. glaucum, cultivar ‘Carajás’) fertilized with protected urea. The experimental design was completely randomized blocks in split-plot arrangement over time. The treatments consisted of 5 levels of nitrogen (0, 100, 200, 400 and 800 kg N/ha/year) and measurements were made over 2 seasons (spring 2015 and summer 2016), with 8 replicates. Leaf and stem elongation and senescence rate of tillers increased as N dosage increased, while tiller density, leaf:stem ratio, live:dead material ratio and phyllochron declined. Forage biomass increased with N dosage reaching 47 t DM green forage/ha at 800 kg N/ha but DM production per unit of N applied declined dramatically as level of N applied increased. There was no effect of season. For crude protein (CP) and fiber concentrations, a positive effect was observed with increasing N application, with maximum CP% of 172 g/kg with 800 kg N/ha in spring. Further studies are warranted to determine if economics indicate that the higher fertilizer levels are justified and even protected urea should still be applied on a number of occasions, but still less often than conventional urea, rather than as a single dose at the beginning of spring.","PeriodicalId":56049,"journal":{"name":"Tropical Grasslands-Forrajes Tropicales","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47862593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Forage production and quality of Urochloa decumbens cultivar ‘Basilisk’ in Okinawa, Japan","authors":"Hanagasaki Takashi","doi":"10.17138/tgft(10)288-296","DOIUrl":"https://doi.org/10.17138/tgft(10)288-296","url":null,"abstract":"Two studies were conducted to assess forage growth and nutritive value of Urochloa decumbens (syn. Brachiaria decumbens) cultivar ‘Basilisk’ in comparison with other grass species grown in Okinawa during 2002–2005 and 2006–2008. Harvests were performed every 40 days from April to October and every 55 days from November to March. In Experiment 1, from 2002 to 2005 total dry matter (DM) yield of ‘Basilisk’ (119.5 t/ha) was significantly higher than that of Digitaria eriantha cultivar ‘Transvala’ (87.4 t/ha; P = 0.01), one of the most popular recommended grass varieties in Okinawa Prefecture. Mean DM digestibility of ‘Basilisk’ was 56.7%, significantly higher than that of other recommended grass varieties (54.5–51.4%). In addition, total digestible DM yield (64.8 t/ha) and crude protein (CP) yield (13.7 t/ha) of ‘Basilisk’ were significantly higher than those of other varieties including ‘Transvala’ (P<0.01). In Experiment 2, total DM yield of ‘Basilisk’ during 2006–2008 was 93.0 t/ha and significantly higher only than that of Urochloa mutica (syn. Brachiaria mutica) (78.6 t/ha; P<0.01), whereas mean DM digestibility (54.8%) was significantly higher only than that of Chloris gayana cultivar ‘Katambora’ (52.8%; P<0.05). Total digestible DM yield (48.8 t/ha) of ‘Basilisk’ was significantly higher only than that of U. mutica (40.3 t/ha; P<0.01) while its total CP yield (10.4 t/ha) was similar to those of other Urochloa cultivars (P>0.05). As a result, in 2016 ‘Basilisk’ was approved to be added to the list of grasses recommended for sowing in Okinawa Prefecture for improving beef production in the area. A suitable supply of seed to allow this cultivar to be sown widely is essential if its potential for improving beef production in the region is to be realized.","PeriodicalId":56049,"journal":{"name":"Tropical Grasslands-Forrajes Tropicales","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46112258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}