Evaluating the effects of fibrolytic enzymes on rumen fermentation, omasal nutrient flow, and production performance in dairy cows during early lactation

This study was performed to evaluate the effects of pre-treating a barley-silage-based diet with an exogenous fibrolytic enzyme derived from Trichoderma reesei (FETR, a mixture of xylanase and cellulase) on lactation performance, omasal nutrient flow and digestibility, rumen fermentation characteristics, and rumen pH profile in Holstein dairy cows during early lactation. The dairy trial was conducted using nine Holstein dairy cows (averaging 46 ± 24 days in milk and 697 ± 69 kg body weight, six cows were fitted with a rumen cannula, and three were non-cannulated). Two groups of cows were randomly assigned to each of the dietary treatments in a crossover design: control (without FETR supplementation) and supplemented [with 0.75 mL of FETR·kg−1 dry matter (DM) of the diet based on our previous study]. The application of FETR tended to decrease the DM intake compared with control. There were no effects of FETR (P > 0. 10) on omasal nutrient flow and digestibility, rumen fermentation characteristics, and rumen pH profile. In conclusion, this study lacks evidence that the fibrolytic enzyme (at a level of 0.75 mL of FETR·kg−1 DM) can affect nutrient digestibility, ruminal fermentation, and the performance of early-lactation cows. Further study with larger animal trials are needed.

Biomass production and essential oil content and composition in basil hydroponic systems using treated domestic effluents

Reusing domestic wastewater is an alternative for irrigated agriculture, helping to decrease pressure on good quality water. This study aimed to evaluate the biomass production and essential oil content and composition in the basil genotypes ‘Alfavaca Basilicão’ and ‘Grecco a Palla’ with different plant spacing in hydroponic systems. Two experiments were carried out between March and May (Experiment I) and July and September of 2015 (Experiment II) in a completely randomized design with four replicates in a 2×3 factorial arrangement. In Experiment I, two hydroponic systems (Laminar Nutrient Flow Technique - NFT and Deep Nutrient Flow Technique - DFT) and three plant spacings in hydroponic channels (0.20, 0.30, and 0.40 m) were evaluated. In Experiment II in the DFT hydroponic system, two types of water (tap water and treated domestic effluents) and three nutrient solution recirculation intervals (at intervals of 2, 4, and 6 h) were evaluated. In general, the dry biomass per plant, oil content and oil yield of the two basil genotypes were not influenced by the hydroponic systems, plant spacing, or water type. In Experiment II, the increase between the recirculation intervals (4 or 6 h) negatively affected genotype ‘Grecco a Palla’. Linalool was the major constituent in the essential oil of the two basil genotypes, ranging from 47.00 to 70.10% (Experiment I) and from 59.47 to 63.64% (Experiment II) in genotype ‘Alfavaca Basilicão’; in genotype ‘Grecco a Palla’, it ranged from 10.19 to 43.03% (Experiment I) and from 19.94 to 53.37% (Experiment II).

EFFECT OF NUTRIENT SOLUTION FLOW INTERVAL ON GROWTH AND YIELD OF LETTUCE (Lactuca sativa) GROWN IN HYDROPONICALLY DEEP FLOW TECHNIQUE

Lettuce (Lactuca sativa L.) is one of the vegetables that are commonly cultivated by using hydroponic systems. Some hydroponic systems require high current expenses in particular for the electricity in order to circulate nutrient solution e.g. in the water culture system – deep flow technique (DFT) -. Electricity costs can be reduced by changing from continuous nutrient flow to intermittent nutrient flow. The aim of this research was to investigate the effect of interval nutrient flow on growth and yield of lettuce. The experiment was conducted in Cirebon from February to April 2018. The experiment was arranged by using randomized complete block design with four treatments: (i) continuous nutrient flow (control), intermittent nutrient flow (nutrient flow during (ii) 15 minutes, (iii) 30 minutes, and (iv) 45 minutes). For each intermittent treatment, the nutrient flow was interrupted for 60 minutes. Each treatment was repeated four times. The result showed nutrient flow interval affected to plant height, shoot diameter, and leaf area at 35 days after planting (DAP). Meanwhile, leaves number, root volume, and fresh weight of harvested crops were not significantly different in all nutrient interval treatments. The highest plant height and shoot diameter were detected in the treatment (ii) nutrient flow during 15 minutes and interruption for 60 minutes, the results were not significantly different to the control – continuous flow treatment. It can be concluded the interval nutrient flow can be used as an alternative of the continuous flow of nutrient solution in hydroponically DFT.