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BACKGROUND Considering that water availability for agricultural needs is being restricted, an alternative to corn in animal nutrition should be explored in the Po Valley. The present study aimed to evaluate the effects of either a partial (Trial I) or a total (Trial II) corn silage substitution with barley silage in dairy cows' diet on milk yield and composition, its coagulation properties, cheese yield and the sensorial profile of 16-month-aged Grana Padano cheese. RESULTS A partial or a total substitution of corn silage with barley silage had no effect on milk yield. Milk fat content in Trial I and milk urea content in both trials were higher with barley silage based diets than in corn silage based diets. No effects were observed concerning the lactodinamographic profile for milk aptitude to cheese-making, cheese yield and its organoleptic traits between feed treatments in Trials I and II. In both trials, hardness, friability and solubility scores were generally lower than reference values, whereas deformability, elasticity and stickiness scores were generally higher than reference values. CONCLUSION A partial or a total substitution of corn silage with barley silage in diets for dairy cows did not induce any negative effects on animal performance, nor on milk-quality traits, cheese quality and yield. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND To investigate corn silage fermentative quality, a principal factor analysis was carried out on a database consisting of 196 corn silages sampled from the core, lateral and apical parts of silo feed-out face and characterised by 36 variables. Eleven principal factor components ( PCs) were retained and interpreted. Two PCs were related to chemical and digestibility variables; four PCs were characterised by end-products associated with clostridia, heterolactic, homolactic or aerobic fermentations; two PCs were associated with mycotoxins produced by Penicillium roqueforti or by Aspergillus fumigatus and Fusarium spp., while three PCs explained ensiling procedures adopted to store corn silages. RESULTS Lower ( P < 0.05) yeast or mould counts and greater ( P < 0.05) aerobic stability were measured in core than in peripheral samples. Excluding PCs related to ensiling procedures, other PCs were able to predict microbiological counts, aerobic stability or biogenic amine content as verified by multiple linear regression analysis. Based on these results, several corn silage quality index calculations were computed by using a summative equation approach in which different PCs as well as diverse relative weights multiplying each PCs were combined. To compute definitive index calculation, only PCs explaining clostridia, heterolactic and homolactic fermentations were used with relative weights of 30%, 50% and 20%. CONCLUSIONS The new proposed fermentative quality index was highly correlated to parameters related to corn silage fermentative quality, such as microbiological counts, aerobic stability or biogenic amines and it properly discriminated well- and poorly preserved forages. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND A survey on 68 dairy farms was carried out to evaluate the ensiling procedures adopted to store corn silage. Samples from core, lateral and apical zones of the feed-out face of silos were analysed. A principal factor analysis ( PFA) was carried out on the entire database (196 silage samples and 36 variables) and 11 principal factor components ( PCs) were retained and interpreted. RESULTS Ensiling procedures influenced the area exposed to risk of air penetration. Cores had higher dry matter, starch and lactic acid content or lower pH, fibre, propionate and butyrate concentrations than peripheral samples ( P < 0.05). The highest ( P < 0.05) mycophenolic acid and roquefortina C concentrations were detected in lateral samples. Chemical and digestibility variables loaded on two PCs; four PCs were characterized by end-products associated with clostridia, heterolactic, homolactic and aerobic fermentations; two PCs were associated with mycotoxins, whereas three PCs explained ensiling procedures. CONCLUSION The main quality traits of corn silages differed throughout the entire silo face. Minimization of the area exposed to risk of air penetration represents the best strategy to preserve the nutritional value and safety of corn silages. PFA allowed a clusterization of original variables into 11 PCs, appearing able to discriminate well and poorly preserved corn silages. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND The effect of a water-saving irrigation regime on yield, chemical composition, rumen in situ dry matter disappearance ( DMD) and neutral detergent fiber disappearance ( NDFD), along with 7 h in vitro starch degradability (7 h IVSD), in maize hybrids selected for whole-plant silage making was investigated. A plot experiment was conducted in a continental climate location and four commercial maize hybrids ( FAO class 700) were used in a completely randomized design with a factorial arrangement of irrigation treatments (fully irrigated ( FI) and water-saving regime ( WS)) and four replicates/treatment. The total amount of irrigation water was 494 mm in FI plots and 367 mm in WS plots, the latter achieved by skipping irrigations at vegetative growth stage, silking and blistering. RESULTS Whole-plant yield, chemical composition, DMD, NDFD and 7 h IVSD slightly differed among hybrids and were not influenced by irrigation treatments. Plant dry matter content was lower in FI than WS plots (320 vs. 341 g kg−1, respectively; P < 0.05). Differences among hybrids were recorded for starch and acid detergent fiber contents ( P < 0.05). CONCLUSIONS The lack of differences on yield and nutritive value in tested maize hybrids grown under different water supply suggests the water-saving regime could be suitable for an optimal use of available water in maize management. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]