The experiment was conducted to evaluate losses and nutritive value of elephant grass silage containing increasing levels of cottonseed meal. The experimental design was completely randomized, with five treatments: 0, 7, 14, 21 and 28% inclusion of cottonseed meal, and four replications. The material was chopped and packed in PVC silos and stored for 80 days. The pH and dry matter (DM), crude protein, lignin and ether extract of the silages increased linearly with the addition of cottonseed meal, while the levels of acid detergent insoluble nitrogen, neutral detergent fiber, acid detergent fiber, cellulose and hemicellulose decreased linearly. The addition of 28% cottonseed meal reduced the in situ disappearance of DM (48h) to values lower than those of silage without additives. The concentration of ammonia nitrogen and the losses from gases and effluent were reduced. The inclusion of 28% cottonseed meal in elephant grass silage containing 18.4% DM improved the fermentation characteristics of silage more efficiently by reducing the moisture content and effluent losses, starting at the 7% level of inclusion.

Produção anual e qualidade de pastagem de Brachiaria decumbens diferida e estratégias de adubação nitrogenada - doi: 10.4025/actascianimsci.v33i3.10194

Annual cool‐season forage crops could fill the gaps in spring forage availability that are typical in perennial pastures in the northeastern United States. Despite their potential as supplemental forages, few studies have examined the productivity–quality tradeoffs of annual forages grown as monocultures or mixtures. This study compared five species of winter annual forages grown as monocultures and mixtures for forage mass production and nutritive value across three harvest timepoints. Beginning in fall 2015, plots were planted in monocultures of cereal rye (Secale cereale L.), barley (Hordeum vulgare L.), triticale [×Triticosecale Wittm. ex A. Camus (Secale × Triticum)], wheat (Triticum aestivum L.), and hairy vetch (Vicia villosa Roth), as well as a mix of all five species. Samples were taken on 1, 7, and 14 June 2016, and on 3, 10, and 17 May 2017 to determine forage mass, nutritive value in the second year, and tradeoffs between biomass and nutritive value. The mixture's forage mass always ranked similarly to the best performing monoculture treatments. All monocultures except hairy vetch had increased forage mass at later harvests. In vitro digestibility of neutral detergent fiber was lower in later harvests. Triticale consistently had the greatest forage mass. Barley had greater energy and lower fiber concentrations than the other species. The results of this study suggest that triticale and barley have the most potential for supplementing spring perennial forage production.

It is necessary to increase the rates of initial growth of pastures for use during the better planting period. Thus, two experiments were used to evaluate the effect of plant growth regulator (PGR; auxins, gibberellins and cytokinins) in seeds types (coated with polymer coating fungicide and conventional method) and nitrogen fertilization methods in Brachiaria decumbens cv. Basilisk on the germination, growth, development and physiological composition. From the regression estimates, lower levels of PGR (10.3; 12.8; 8.85 and 9.57 ml/kg for germination percentage, germination speed index, leaf and pseudostem, respectively) were recommended in coated seeds when compared to conventional method (untreated seeds, with polymer coating and fungicide). Leaf and pseudostem mass production had a significant interaction effect between seed type and the use of growth regulator. Coated seeds (with fungicide and polymers after scarification) had greater performance with absence or at lower levels (8.85 and 9.57 ml/kg seed) of growth regulators. This was not observed for conventional seeds, the higher doses (15.5 and 18.1 ml/kg) presented higher development for the same characteristics. In second experiment, rates of photoassimilate were increased by soil fertilization and use of PGRs. No influence of foliar fertilization was observed when used exclusively, but N‐fertilization multiple and soil promotes an increase in chlorophyll content and mass yield, respectively. The use of exogenous hormonal compounds acts on the organogenesis of plant tissues and increases the formation of plant tissues and acts in the promotion of germination and development of structures, making it a key tool in pasture establishment.

Foram estudados os efeitos da adição de farelo de cacau e de cana-de-açúcar sobre as perdas de silagem de capim-elefante. Utilizou-se um esquema fatorial 2 x 4, sendo 0 e 15% de farelo de cacau e 0, 15, 30 e 45% de cana-de-açúcar, com quatro repetições, no delineamento inteiramente ao acaso. O capim-elefante apresentava 29,2% de matéria seca, e as silagens foram produzidas em silos experimentais de PVC, utilizando-se compactação de 600 kg de silagem/m³. A abertura dos silos ocorreu aos 60 dias após a ensilagem, quando foram determinados o teor de nitrogênio amoniacal e o pH das silagens. O farelo de cacau foi eficaz na redução da umidade e da concentração de nitrogênio amoniacal. Recomenda-se a inclusão de até 22,4% da cana-de-açúcar, cv-IAC86-2480, na ensilagem de capim-elefante com 29% de matéria seca, podendo-se aumentar para 45%, desde que se utilizem 15% de farelo de cacau.

The aim was to evaluate the fermentative dynamics and nutritional characteristics of mixed maize silages with and without commercially viable cobs associated with butterfly pea hay. A completely randomized experimental design was used in a 2 × 2 factorial scheme, with 4 replications, which corresponded to the maize cobs factor and the butterfly pea hay factor (inclusion of 30% of butterfly pea hay during the ensiling process and without the inclusion of butterfly pea hay). The inclusion of butterfly pea hay increased the dry matter contents, reduced the silage density and its interaction with the absence of viable cobs promoted less losses and greater dry matter recovery ( P < 0.05). The lowest value of butyric acid was found in the interaction of silage without viable cobs and butterfly pea hay ( P < 0.05). The inclusion of butterfly pea hay reduced fiber contents and increased protein contents ( P < 0.05). The inclusion of 30% butterfly pea hay promotes better values of organic acids, nutritional components and lower fermentation losses when the maize is ensiled without cobs that are viable for commerce.