Biological nitrogen fixation and plant hormone synthesis promoted by Azospirillum spp. bacteria play a role in enhancing crop productivity and reducing losses. This may constitute a strategy to enhance crop productivity and reducing losses, thereby increasing nitrogen fertilization efficiency. This research aimed to evaluate the effects of Azospirillum brasilense Ab-V5 and Ab-V6 strain inoculation and nitrogen fertilization on the agronomic characteristics and productivity of two maize hybrids (Zea mays L.) AS 1572 and AG 9030. Experiments were carried out at Santa Maria, RS, Brazil in the 2013/2014 and 2014/2015 growing seasons using a 2 × 2 × 5 factorial arrangement to distribute two maize hybrids, inoculated, or not, with Azospirillum brasilense, and five nitrogen doses (0, 60, 120, 240, and 480 kg ha⁻¹). Kernel yield, mass, and dimensions, as well as kernel number on the cobs, stalk diameter, plant height, ear insertion height, prolificacy, nitrogen use efficiency (NUE), and their correlations were measured. Compared to uninoculated plants, higher kernel yield (p < 0.05) was observed for AS 1572 hybrid when inoculated with A. brasilense, with an increase of 0.978 Mg ha⁻¹ or 10.95%. This effect was primarily due to the higher NUE rate and the increase (p < 0.05) in the number of kernels per cob. The AG 9030 hybrid showed no response to inoculation. A. brasilense inoculation increased the NUE rate of the AS 1572 hybrid in the condition N zero dose at N 60 kg ha⁻¹ dose. Nitrogen fertilization increased crop productivity, notably by raising kernel mass and other productivity components, but reduced the NUE rate. The maximum technical efficiency obtained for the AS 1572 hybrid was of 10.705 Mg ha⁻¹ with a N dose of 342 kg ha⁻¹, whereas the AG 9030 hybrid produced a maximum grain yield of 10.089 Mg ha⁻¹ with a dose of 350 kg ha⁻¹ of N. We conclude that the inoculation with A. brasilense increases NUE, maize grain yield, and agronomic characteristic in the AS 1572 hybrid.

The present study aims to evaluate the nutritional value of different tree and shrub leaves in Brazilian ruminant production systems. Eight potentially edible trees and shrubs were identified from interviews with 30 ruminant producers: Aroeira (ARO; Lithraea molleoides), Black Mulberry (BMU; Morus nigra), Candeia (CAN; Eremanthus erythropappus), Jatobá (JAT; Hymenaea courbaril), Gliricídia (GLI; Gliricidia sepium), Santa Bárbara tree (SBT; Mélia azedarach), Tithonia (TIT; Tithonia diversifolia), and White Mulberry (WMU; Morus alba). Four leaf samples of each edible tree were sampled, and chemical analyses and in vitro assays were performed. Edible trees (except CAN and JAT) had lower neutral detergent fiber content than Mombasa grass. In addition, SBT, BMU, WMU, and TIT had lower fiber content than the other evaluated edible trees. Consequently, SBT, TIT, BMU, and WMU had improved dry matter degradation. Among the edible trees and shrubs, SMW and WMU increased the potential for gas production (a parameter). On the other hand, CAN decreased the estimated gas production 48 h after incubation. Furthermore, TIT decreased methane production up to 24 h after in vitro fermentation. Thus, except ARO, CAN, and JAT, the edible trees evaluated in the present study are potential feeds in moderate- to high-producing animals. Additionally, TIT fermentation reduces in vitro methane production.

This study aimed to evaluate the storage time effects on whole‐plant sorghum silage nutrients fermentation profile, fermentation losses, mycotoxin concentrations and aerobic stability. Sixteen experimental silos (cylindrical bag with 32 cm i.d. and six kg of silage) were used in a completely randomised design to evaluate the following storage times: 45, 90, 180 and 360 days. Storage time linearly increased silage Ammonia‐N, propionic and butyric acid concentrations. In addition, treatments had a quadratic effect on silage pH and concentrations of lactic and acetic acids. Storage time did not affect fermentation losses, dry matter recovery and zearalenone concentration. However, storage time linearly decreased silage dry matter concentration and linearly increased deoxynivalenol silage content. Aflatoxin and fumonisin were not identified in silage samples. Storage time linearly increased silage pH regardless of evaluation period, and temperature, 24 h after aerobic exposure. Thus, the storage time of whole‐plant sorghum silage affects the fermentation profile, has no effect on fermentation losses, increases deoxynivalenol content and reduces silage aerobic stability.

With the aim to evaluate the effects of the use of additives (milk whey and inoculant containing Lactobacillus casei and Lactobacillus acidophillus) in sorghum silage, an experiment was conducted in which the productive parameters, fermentative and the nutritional quality of silage were analyzed. The experimental design was completely randomized, testing different levels of inclusion of whey and live Lactobacillus strains based on forage green matter, constituting the following treatments: 1) Sorghum without inclusion of additives (CON); 2) Sorghum + 5 x 102 cfu/g L. casei and L. acidophillus (LAC); 3) Sorghum 5 x 102 cfu g-1 whey (SL); 4) Sorghum + 5x102 cfu/g-1 L. casei and L. acidophillus and 5x102 cfu/g whey (LAC + SL). When Lactobacillus was included the mixture used was 50 ml of water and 10 grams of Lactobacillus. To measure silage fermentation, pH, dry matter recovery, gas and effluent losses, ammonia nitrogen, buffer power and density were estimated. The addition of whey and Lactobacillus inoculant in sorghum silage did not significantly change the bromatological values of silage when compared to the original material. The inclusion of additives increased (P <0.05) the effluent losses during fermentation. The use of whey presents a viable alternative for producers, as it does not compromise the fermentation and chemical composition of sorghum silage and assists in the reduction of dairy residues in nature.

The objective of this study was to evaluate the effect of maize (Zea mays L.) carbohydrate contents and the estimates of milk production on different storage periods. The experimental design was co...

The experiment evaluated the effects on the chemical composition (fermentation, kinetic parameters, and protein and carbohydrate fractions) of corn silage after various storage durations (45, 90, 180, and 360 days). Experimental mini silos of the corn plants were made and opened after various storage periods. The experimental design was completely randomized with four treatments and four replications per treatment. Variables such as pH, lactic acid and acetic acid showed a quadratic effect, whereas effluent and gas losses increased linearly with prolonged storage. Proteolysis was observed with an increase in storage, resulting in a rise in ammonia-N, soluble N, and non-protein N concentration and reduction in true protein. The soluble carbohydrate fractions were reduced, and digestible and indigestible fibre were increased. For the kinetic degradation parameters of the silages obtained through in vitro gas methodology, the highest fermentation rate occurred in the first 12 hours of incubation, and the highest volume of gas produced within 96 hours was obtained for silages with shorter storage (45 days). The increase in storage resulted in greater losses and lower ruminal degradability in vitro, causing a decrease in protein quality and nutritional value.