Browsing by Subject "biojalostamo"

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  • Savonen, Outi (2020)
    Novel fibrous feeds for ruminants The objective of this licentiate thesis was to study the effects of novel fibrous feeds on feed intake, digestibility, rumen fermentation and milk production of lactating dairy cows. The novel feeds used in the milk production trials were silage solid fraction originated from a green biorefinery process (solid fraction) and microcrystalline cellulose (MCC) from coniferous trees. Solid fraction replaced unprocessed grass silage whereas MCC replaced barley in the diet as concentrate. The idea behind this thesis was a need to examine ruminant feeds unsuitable for human food. The need of more efficient food production will increase significantly due to the global population growth. Novel feeds for ruminants could form a part of a sustainable food system because the use of grass solid fraction would intensify the use of natural resources. The use of wood-based products would release arable land for producing human food. Enhancing the efficiency of grassland management in Finland might help to answer many problems caused by climate change. Furthermore, the processing of grass based biomaterials would contribute to the overall benefits from grasslands. In the first experiment (Exp. I), grass silage was fractionated using a farm scale twin-screw press. Due to the separation of liquid fraction the concentration of both dry matter and neutral detergent fibre (NDF) increased whereas the crude protein concentration was reduced in the solid fraction compared to the unprocessed silage. In the feeding trial, solid fraction replaced 0, 0.25 or 0.5 of the portion of forage. The cows were able to increase their feed intake when the proportion of solid fraction increased to 0.25. However, at the point where the proportion of solid fraction reached 0.5 the cows could not increase feed intake further. The digestibility of crude protein decreased linearly whereas the digestibility of NDF tended to increase with the increase in the NDF content of the diet. The pH or the content of ammonia in the rumen fluid did not change when silage was replaced with the solid fraction. There was also no difference in the amount of total volatile fatty acids in the rumen fluid but the proportion of acetic acid increased with the increased proportion of solid fraction. Due to the increase in NDF content, the intake of metabolizable energy decreased quadratically and the amount of energy corrected milk tended to decrease. The separation process probably mechanically crushed the plant structure thus enhancing its rumen digestibility. This might explain the increase in feed intake and prevent the energy corrected milk production from declining when the portion of solid fraction was 0.25. In the second experiment (Exp. II), the effects of microcrystalline cellulose manufactured from coniferous wood pulp using a method developed at Aalto university (AaltoCell TM) was studied on dairy cows. In the feeding trial on lactating dairy cows MCC replaced barley in the concentrate. The proportion of MCC in diet dry matter was 0, 0.01 or 0.1. Microcrystalline cellulose has a very tight structure because the crystalline regions of the cellulose chains are strengthened by numerous inter- and intramolecular hydrogen bonds. The increase in MCC concentration did not affect dry matter intake. However, the digestibility of NDF improved with the increase in NDF content of the diet. Despite of increased intake of metabolizable energy, energy corrected milk production decreased linearly with the increase of MCC. The methods used in this study could not reveal the cause of the reduction in milk production. The increase in fibre digestibility can probably be explained by the better digestibility of MCC fibre compared to other fibres in the diet. Due to the small particle size of MCC, there is more surface area for microbial fermentation which may enhance the rumen digestibility. The cows were able to use the novel fibrous feeds examined in both experiments. The improvements in fibre digestibility compensated the increased fibre concentration in both experiments and there was only a minor reduction in milk production. The low concentration of crude protein in solid fraction improved the nitrogen use efficiency in milk production. The usage of MCC might also increase nitrogen use efficiency because it does not contain any nitrogen. The use of novel fibrous feeds in ruminant nutrition would help to enhance the use of natural resources and release arable land for human food production Grass cultivation as well as the usage of grass based biomaterials would be more efficient if the fractionation of grass would be more widely used.
  • Timonen, Petteri (Helsingin yliopisto, 2019)
    The self-sufficiency of protein concentrates in Finland is low. Forage plants grow well under Finnish climatic conditions and they can produce a lot of crude protein per hectare. It is possible to press juice with a high protein concentration from ensiled forage and this juice is suitable feed for pigs. The aim of this thesis was to find out how forage plant species and silage additives affect juice proportion, dry matter yield and dry matter concentration of the juice when juice is pressed from silage. The effects of different kinds of pressing equipment and silage dry matter concentration to pressing results was also examined. The study was conducted as part of the Innofeed project. The experiments were conducted at Natural Resources Institute Finland in Jokioinen. The silages were harvested during growing season 2016. First and second cut grass and clover forages were ensiled in experimental size silos and third cut grass was ensiled in round bales. Two different prewilting periods were used for first cut grasses. Additive treatments were: water as a control, formic acid based additive, fibre hydrolysing entzyme (2nd and 3rd cut) and lactic acid bacteria inoculant (1st cut). Liquid and solid fractions were separated with four different kind of equipments. Silages and liquid fractions were analysed from all cuts and solid fraction was analysed from 3rd cut. Silages were mostly well preserved and only a few were spoiled. Silage additives prevented spoilage. Dry matter concentration of silages differed a lot between cuts (137 – 306 g/kg). There were higher concentrations of crude protein and ash in clover silages than in grass silages, but dry matter concentration was lower. Juice proportion (0,487 vs. 0,350 kg/kg) was higher from clover silages than from grass silages. Crude protein (179 vs. 163 g/kg ka) and ash (189 vs. 128 g/kg ka) concentrations in juice were higher in clover than in grasses. Also dry matter (0,197 vs. 0,130 kg/kg), crude protein (0,167 vs. 0,160 kg/kg) and ash (0,433 vs. 0,270 kg/kg) yields were higher from clover silages than from grass silages. On the contrary, dry matter concentration (72,0 vs. 87,5 g/kg) in juice was lower in clover than in grass. Silage additives secured the quality of silages but they did not help to get more juice out of silage. Formic acid (0,384 kg/kg) was even worse than control (0,404 kg/kg) regarding juice proportion from silages. Red clover was better plant species than grasses for production of silage juice, but the difference may originate from differences in dry matter concentration between plant species. The pressing equipment greatly affected the results. When the efficiency of the pressing equipment rised differences between the silage additives decreased. When the dry matter concentration of the silage rised the proportion of juice decreased but dry matter concentration of juice rised. There is possibilities in silage juice production for pig protein feed, but more information about the effects of silage additives on crude protein quality of silage juice is still needed.