Search

Pollinator declines and expectations for more sustainable agriculture, including pasture-based enterprises, bring attention to strategies to enhance the habitat value of grazing lands. We evaluated native warm-season grass (NWSG) pastures with (FORB) and without (CONT) interseeded native forbs in 2021–2023. An analysis was conducted using R with the significance set at p ≤ 0.05. The grass appeared to be weakened predominantly by grazing management practices. Forb density and mass had an inverse relationship in seasons two and three. Total forage mass declined in response to increased grazing days and weakened stands. The forage nutritive compositions differed, with more stable, season-long crude protein and lower fiber concentrations in late-season FORB, which supported higher bodyweight gains and season-long average daily gain. Black-eyed Susan (Rudbeckia hirta; BESU), lanceleaf coreopsis (Coreopsis lanceolata; LCOR), and showy ticktrefoil (Desmodium canadensis; STTF) were the most abundant forbs, and BESU, LCOR, and purple coneflower (Echinacea purpurea; PURC) produced long flowering windows. Cattle grazed STTF, cup plant (Silphium perfoliatum; CUPP), and oxeye sunflower (Helopsis helianthoides) the most. Under continuous stocking, a blend of BESU, LCOR, PURC, STTF, and CUPP produced acceptable cattle gains and provided pollinator resources, suggesting that this model may be a viable means to enhance the sustainability of pastures. [ABSTRACT FROM AUTHOR]

Pollinator declines and expectations for more sustainable agriculture, including pasture-based enterprises, bring attention to strategies to enhance the habitat value of grazing lands. We evaluated native warm-season grass (NWSG) pastures with (FORB) and without (CONT) interseeded native forbs in 2021–2023. An analysis was conducted using R with the significance set at p ≤ 0.05. The grass appeared to be weakened predominantly by grazing management practices. Forb density and mass had an inverse relationship in seasons two and three. Total forage mass declined in response to increased grazing days and weakened stands. The forage nutritive compositions differed, with more stable, season-long crude protein and lower fiber concentrations in late-season FORB, which supported higher bodyweight gains and season-long average daily gain. Black-eyed Susan (Rudbeckia hirta; BESU), lanceleaf coreopsis (Coreopsis lanceolata; LCOR), and showy ticktrefoil (Desmodium canadensis; STTF) were the most abundant forbs, and BESU, LCOR, and purple coneflower (Echinacea purpurea; PURC) produced long flowering windows. Cattle grazed STTF, cup plant (Silphium perfoliatum; CUPP), and oxeye sunflower (Helopsis helianthoides) the most. Under continuous stocking, a blend of BESU, LCOR, PURC, STTF, and CUPP produced acceptable cattle gains and provided pollinator resources, suggesting that this model may be a viable means to enhance the sustainability of pastures.

The Pecari tajacu is considered a pseudo-ruminant, because it can digest vegetable fiber and produce fatty acids in its compound stomach. It has been proven that it consumes the fresh foliage of native trees; however, there is no information on the consumption of silage with chacá (Bursera simaruba), jabín (Piscidia piscipula), moringa (Moringa oleifera) and pixoy (Guazuma ulmifolia). The objective was to evaluate the preference of silage consumption by collared peccary based on moringa, pixoy, jabín and chacá with corn. Four adult male collared peccary specimens with an average weight of 17 ± 1.8 kg were used. Two experiments were carried out in the "Xmatkuil" Wildlife Management and Conservation Unit. In the first, the 4x4 Latin square design was applied for four hours, for four days with four silages. In the second experiment, the test was carried out with three silages using a 3x3 Latin square, the preferred silage from the first experiment was removed. The preferred silage in the first trial was M. oleifera (P<0.05) and B. simaruba in the second (P<0.05). No significant relationship (P>0.05) was found between the nutrient levels and the dry matter intake of the silages. [ABSTRACT FROM AUTHOR]

Copyright of Tropical Grasslands / Forrajes Tropicales is the property of International Centre for Tropical Agriculture - CIAT 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.)

En la actualidad, una prioridad para mejorar la producción ganadera en el centro-norte de Argentina es la búsqueda de leguminosas forrajeras adaptadas a la región.Este trabajo tuvo como objetivos: a) analizar la variabilidad de caracteres morfológicos relacionados con el crecimiento inicial en poblaciones de dos especies de forrajeras nativas, Desmanthus virgatus y D. paspalaceus, y b) evaluar la implantación a campo en dos ambientes. Se encontró variación en los caracteres relacionados con el crecimiento inicial en ambas especies se identificaron poblaciones promisorias para incorporar en programas de mejoramiento. Una parte importante de la variación encontrada corresponde a variaciones interpoblacionales e intrapoblacionales. Las correlaciones entre caracteres indican que es posible mejorar simultáneamente por producción de biomasa aérea sin comprometer la acumulación de reservas en la raíz. Todas las poblaciones mostraron un bajo establecimiento a campo en los dos ambientes analizados. Se discuten las causas probables de dicho comportamiento.The search for forage legumes to improve animal production is a priority in the centre-north of Argentina. This study aims to determine the variability for morphological traits related with the early vegetative growth in populations of two native forage legumes, Desmanthus virgatus y D. paspalaceus and analyze their field establishment in two environments. Variation was found in all of the traits analyzed and useful populations were identified with a view to their incorporation into breeding programs. Big fractions of the total phenotypic variation for almost all traits was due to interpopulational and intrapopulational variation. Correlations among characters indicate that a simultaneous improvement is possible by means of aerial biomass without compromising reserve accumulation in roots. All populations had low field establishment rate on the two locations used. The causes of this problem are discussed in this paper.

Caracterizaram-se os taninos condensados (TC) e determinaram-se a composição bromatológica e a digestibilidade in vitro da matéria seca (DIVMS) das espécies maniçoba (Manihot pseudoglazovii Pax & Hoffman), flor-de-seda (Calotropis procera), feijão-bravo (Capparis flexuosa, L) e jureminha (Desmanthus virgatus (L.) Willd). As concentrações em tanino solúvel, tanino ligado ao resíduo e tanino total (TT) das espécies foram determinadas pelo método butanol-HCL e a adstringência pelo método de difusão radial. Para a DIVMS, foi utilizado método de dois estágios. Foram observadas diferenças entre as espécies (PCondensed tannins (CT) of the species maniçoba (Manihot pseudoglaziovii), flor-de-seda (Calotropis procera), feijão-bravo (Capparis flexuosa) and jureminha (Desmanthus virgatus) were characterized and the chemical composition and in vitro dry matter digestibility (IVDMD) of those species were determined. Concentration of soluble tannin (ST), bound tannin (BT) and total tannin (TT) of the plants was determined using butanol-HCL method; astringency was determined, using radial diffusion method, and the IVDMD was determined using two-stages method. Concentration and astringency of condensed tannins varied between species (P

Bromus auleticus é uma espécie perene, nativa do estado do Rio Grande do Sul, que tem demonstrado adaptabilidade, potencial para produção de forragem de qualidade e alta diversidade morfológica. Neste trabalho, foram analisados padrões de bandas de sistemas enzimáticos e de marcadores RAPD, com o objetivo de determinar a variabilidade genética em 16 acessos de Bromus auleticus do Rio Grande do Sul. A variabilidade foi avaliada pelo índice de similaridade de Jaccard, utilizando-se o método UPGMA nas análises de agrupamento. Os índices de similaridade variaram de 0,0 a 0, 50 com base em isoenzimas e de 0,15 a 0,71 com base em marcadores RAPD. Os dados foram eficientes para a formação de grupos, indicando a variabilidade genética dos acessos analisados. Entretanto, houve baixa relação entre os agrupamentos e os locais de coleta. A variabilidade genética dos acessos é importante sob o ponto de vista do melhoramento genético, permitindo a seleção futura dos genótipos a partir de seus respectivos desempenhos. A utilização simultânea de isoenzimas e RAPD foi eficiente na caracterização da diversidade genética dos acessos analisados.Bromus auleticus is a perennial, native species of the state of Rio Grande do Sul, which has demonstrated adaptability, potential yield of good quality forage as well as high morphological diversity. This work has analyzed band patterns from enzymatic systems and RAPD markers, with the objective to access the genetic variability in 16 accessions of Bromus auleticus from Rio Grande do Sul. The variability was evaluated using Jaccard similarity index. The method of grouping based on the average (UPGMA) was used in cluster analyses. The similarity index ranged from 0.0 to 0.50 using isozumes and from 0.15 to 0.71 using RAPD markers. The data have been efficient for the formation of different groups, indicating the genetic variability of the accession analyzed. However, these groupings have little relationship with the respective collecting places. The genetic variability of the accessions is important to the genetic improvement, allowing future genotype selection based on their respective performances. The simultaneous utilization of isozymes and RAPD was efficient in characterizing the genetic diversity of the accessions evaluated.

The use of native and adapted forages is an alternative for sustainable production systems in northeast Brazil. The goal of this study was to evaluate the substitution of Tifton 85 by maniçoba hay on the performance and carcass traits of Morada Nova hair sheep. The 16 lambs that were used in this study initially weighed 19.36 ± 1.48 kg, were housed in individual pens, and were slaughtered at 58 days of confinement. The dry matter intake (839.84 g/day and 3.81 % WB) was higher ( P < 0.05) in sheep fed maniçoba hay. The feed conversion was 7.39 for sheep fed maniçoba hay. The empty body weight (21.61 kg) and cold carcass weight (11.40 kg) did not differ ( P > 0.05) between sheep fed different hay types. The replacement of Tifton 85 by maniçoba hay did not influence the loin eye area (cm) or carcass compactness index (kg/cm). The replacement of Tifton 85 by maniçoba hay in Morada Nova sheep diet did not affect the weight gain or carcass characteristics. The maniçoba hay can be considered a forage resource for feeding sheep in Brazilian semiarid tropics. [ABSTRACT FROM AUTHOR]

The chromosome number of 14 accessions of Bromus auleticus Trin. ex Nees, native of Rio Grande do Sul, was 2n = 6x = 42, same ploidy level found in other South-American Bromus species. Its chromosomes were metacentric or submetacentric, ranging from ca. 4 mm to ca. 8 mm in length. Up to two satellite-bearing chromosome pairs were sometimes observed. However, as already reported for other species, the high symmetry and homogeneity of the karyotypes made it difficult to detect possible intraspecific differences.