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This paper describes, for the first time, a simple sonochemical method for the synthesis of nanoparticles of a series of rare earth orthoferrites. This sonochemical process is enabling synthesis of nanoparticles of the rare earth orthoferrites at a substantially lower calcination temperature by using simple precursors, iron pentacarbonyl and rare earth carbonates. It is particularly noteworthy that the cogeneration of the garnet phase has not been observed, as is usual with the conventional methods. The drastic reduction in the calcination temperature could be due to the ultrasonic generation of amorphous iron oxide from Fe(CO)5. Nanosized GdFeO3, ErFeO3, TbFeO3, and EuFeO3 were prepared by this method and their magnetic properties were also studied in detail.

The ensiling characteristics of safflower (Carthamus tinctorius) wilted to 290 and 411 g dry matter (DM) kg−1 fresh material were studied in 1·5 l glass jars. The experiment included a control and the application of Lactobacillus plantarum at 3·3 × 105 colony-forming units (cfu) per g of crop. After 60 days of ensiling, the pH of safflower silages was 4·6 and 4·0 in the control and inoculated silages respectively, with corresponding values for lactic acid, the major fermentation product, of 20 and 45 g kg−1 DM. The silages from the anaerobic jars were stable upon aerobic exposure. It is concluded the safflower silage has potential as an alternative fodder in semiarid regions.

A real-time control system for individual food intake of group-housed dairy cows was designed and implemented. The system consists of 40 feeding stations, each position comprising an automatic opening and closing yoke-gate. The specially designed electro-pneumatic yoke-gate combines off-the-shelf identification, weighing and control systems in a unique mechanical implementation. The yoke-system enables real-time control of food intake, which can be specified for each cow, and for each station through an interactive user interface. In addition, the system enables measurement and utilization of on-line data related to individual food intake and feeding behavior information such as food access frequency, meal duration, intake rate and food quantity for each visit of a cow kept in the group. The advantages of this design are: (i) the system is based on commercial components, (ii) simplicity and high reliability resulting in low maintenance, and (iii) continuous measurement of all feeding parameters, including during the meal. Although the yoke-system was built for a research institute, it is a step towards a commercial system.

The effect of applying a commercial inoculum (at 1.5 × 105 cfu g-1) containing Streptococcus faecium (Lacticil M74®. Medipharm, Sweden), and cell wall degrading enzymes (Celluclast® and Viscozyme®, Novo, Denmark) to pea, ryegrass and wheat silages was studied under laboratory conditions. Celluclast was applied at 0.03 Novo Cellulose Units (NCU) and Viscozyme at 0.024 Fungal β-glucanase (FBG) per g fresh crop. The peas and wheat used were at three stages of maturity, and the ryegrass used was either direct-cut or wilted. This yielded a wide range of dry matter (DM) and fibre content. Inoculum use improved the ensiling process of most of the forages tested, as indicated by a faster and greater decrease in pH, and by a faster and larger build-up of lactic acid. Inoculum, however, lowered the aerobic stability of wheat silages. The addition of the enzymes alone did not affect the ensiling process. In silages of peas and wheat at the flowering stage, the combination of inoculum and enzymes resulted in a improvement to the ensiling process, as compared with inoculum only. The combined treatment of inoculum and enzymes resulted in a lower percentage of neutral detergent fibre (NDF) and acid detergent fibre (ADF) in the silages of the flowering peas and of the direct-cut ryegrass. The NDF and ADF contents in the inoculum plus enzyme-treated pea silages made at the flowering stage were 322 and 296 g kg-1, compared with 365 and 327 g kg-1 in the control silages. The NDF and ADF contents in the silages made from the direct-cut ryegrass were 312 and 205 (treated with inoculum plus enzymes) vs 383 and 257 g kg-1 (control). However, the DM rumen digestibility of the silages was not improved by any of the treatments. It is concluded that a suitable inoculum could be beneficial to the ensiling process. The benefit expected from the application of cell wall degrading enzymes to silages is as yet unclear.

Nanocrystalline perovskite-type LaFeO3 with particle size of about 30 nm was prepared by a sonochemical method using iron pentacarbonyl and lanthanum carbonate as starting materials. The overall process involves three steps: formation of lanthanum carbonate using lanthanum nitrate and urea; reaction of the so-formed lanthanum carbonate with iron pentacarbonyl resulting in the formation of a precursor; calcination of the precursor to obtain nanocrystalline particles of LaFeO3. Transmission electron microscopy revealed the particles to have a mean size of about 30 nm. Study of the magnetic properties of nanocrystalline LaFeO3 particles shows a coercivity of ∼250 Oe, while the saturation magnetization is ∼40 memu g−1.