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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

Physiological Impacts and Lactational Performance of Dairy Cow Fed Brown Midrib Corn Silage During Dry Period Through Early to Midlactation

Kelley, Alexandra Windley 01 May 2014 (has links)
Developing solutions to the metabolic stress experienced by cows during the transition period is very important because it can negatively influence lactational performance. The objectives were to: 1) compare physiological changes through body weight (BW) and concentrations of non-esterified fatty acids (NEFA) and β-hydroxybutyric acid (BHBA) and 2) evaluate feed intake, milk production, and energy balance (EB) of cows fed brown midrib corn silage (BMRCS)-based diets when compared with conventional corn silage (CCS)-based diets during the transition. At 4 wk prior to parturition, 40 dry multiparous Holstein cows were randomly assigned treatments. The treatment groups consisted of 2 close-up transition diets (CCS-based and BMRCS-based diet) offered to 2 groups of 20 cows each beginning at 4 wk prepartum. After calving, 10 cows from each prepartum group were individually fed one of four dietary treatments. The four dietary treatments postpartum were defined as follows: 1) CC = CCS-based close-up diet + CCS-based lactation diet; 2) CB = CCS-based close-up diet + BMRCS-based lactation diet; 3) BB = BMRCS-based close-up diet + BMRCS-based lactation diet; 4) BC = BMRCS-based close-up diet + CCS-based lactation diet. Cows were sampled weekly for feed intake, and feed composition was taken monthly. After calving, milk yields were recorded daily and milk components were analyzed monthly. Body weights were taken twice per week on wk -4, -2, 1, 2, 3, 4, 8, 12, 16, and 20. Blood serum was sampled 3 times per week from wk -4 through 4 and then on wk 6, 8, 14, and 20. Rumen fluid was sampled on wk -4, 4, 8, 14, and 20. Feeding BMRCS-based diets during the transition did have a positive influence on dry matter intake, milk production, and energy balance. Interestingly, feeding BMRCS-based diets only during the close-up period and feeding a CCS-based diet during the lactation had similar positive effects as feeding a BMRCS-based diet through the dry period and during the lactation. This finding is meaningful because producers, especially in the Intermountain West, have experienced BMR crop yields that have been less than that of conventional crop yields and may be unwilling to utilize BMRCS in dairy rations. However, if feeding a BMRCS-based diet for a limited amount of time is beneficial, producers could be more willing to utilize this silage hybrid as an important transition period management tool.
172

Heterogeneity and hygienic quality of grass silage /

Pauly, Thomas M., January 1900 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Härtill 4 uppsatser.
173

Wrapped forages for horses /

Müller, Cecilia, January 2007 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2007. / Härtill 5 uppsatser.
174

Hodnocení kvality konzervované objemné píce při různých způsobech konzervace a skladování. / The evaluation of quality of conserved bulky fodder by different way of conservation and storage

KODADOVÁ, Lenka January 2017 (has links)
The thesis in the first part deals with the characteristics of major equipment as a source of coarse fodder for preservation. Given the difficult preservability is more prominent characteristic of legumes and their importance in the cultivation of coarse fodder. It describes the significance of clover-grass mixtures in the production of coarse fodder. Methods of harvesting and conservation of grassland biomass. It is also described silage corn, the preservability, harvest methods and importance in animal nutrition. Quality coarse fodder and the factors affecting it. Influence the quality of the biomass input on preservation processes. Furthermore, also deals with the procedures and principles of the production of silage, hay and silage, preservatives and finally summarizes the deterioration of the quality of silage and forage and impact deteriorated for receiving fodder and animal performance.The second part is focused on the monitoring of sensory properties and quality assessment laboratory conserved forage preservation in different ways - loose hay, hay bales, silage pits in silage, clover silage bales and silage in silage pits on lands selected agricultural cooperative. In conclusion, the most important measures designed to improve the quality of canned food.
175

Vliv aditivních látek na kvalitativní ukazatele travních siláží / The influence of silage additives for qualitative parameters of grass silages

HANETŠLÉGROVÁ, Petra January 2012 (has links)
The main goal of this thesis was to evaluate the influence of additives on the qualitative indicators of grass silage. The evaluation concentrated in particular on lactic acid, pH and the degree of proteolysis. The selected qualitative indicators were monitored in 36 samples of grass silage from the region of South Bohemia. Silage samples were divided into three groups. The first group was a guide sample without any additives. The second group was treated with bacterial additives and the third group with bacteria-enzyme additives. Classification of silage samples was done according to "Norma 2004". Each sample was evaluated in terms of quality of fermentation and the content of nutrients. Statistically significant differences (p <0.05) were found in the content of lactic acid, pH and the degree of proteolysis between the group of silages without additives and the group treated with silage additives.
176

Desempenho de novilhas leiteiras alimentadas com diferentes volumosos / Performance of dairy heifers fed with different forages

Burgos, Eusebio Manuel Galindo 24 July 2013 (has links)
Made available in DSpace on 2015-03-26T13:55:20Z (GMT). No. of bitstreams: 1 texto completo.pdf: 562262 bytes, checksum: 3877ee62b4d2fbbf059feb8b198e8118 (MD5) Previous issue date: 2013-07-24 / This study aimed to evaluate the effects of different forages on intake, digestibility and performance of dairy heifers. Sixteen dairy heifers were used, and they had initial body weight of 150 ± 19 kg and 8 mo. The animals were divided into a randomized block design with four replications, where each animal was used as experimental unit and blocks formed in accordance with the initial body weight of the animals. They were fed for 70 days. Four sources of roughage were used: corn silage (CS), sorghum silage (SS), sugar cane in nature (SC) sugar cane silage (SCS). The amounts of concentrate were fixed at 0.5% of body weight (BW) for CS and SS, 0.7% BW for SC, and 1.0% BW for SSC. The animals fed diets based on CS and SS had higher average daily gain than those fed with diets containing SC and SCS. Intake and digestibility of dry matter (DM), organic matter (OM) and metabolizable energy (ME) were higher for heifers fed CS and SS. There were differences in intake and digestibility of crude protein (CP) and neutral detergent fiber (NDF) for heifers fed SS. For non-fiber carbohydrates (NFC), there were greater intake and digestibility in heifers fed on CS. There were no diet effect for withers height and body length. There was an effect of CS and SS for chest girth. It is concluded that diets based on corn silage and sorghum silage offer higher performance than diets based on sugar cane in nature or sugar cane silage for dairy heifers. / Objetivou-se avaliar os efeitos de diferentes volumosos sobre o consumo, digestibilidade e desempenho de novilhas leiteiras. Foram utilizadas dezesseis novilhas leiteiras da raça Holandesa, com peso médio inicial 150 ± 19 kg e idade media 8 meses, distribuídas em delineamento em blocos casualizados, com quatro repetições, sendo cada animal considerado uma unidade experimental e os blocos formados com base ao peso inicial dos animais, durante 70 dias. Os tratamentos constituíram de quatro volumosos: silagem de milho (SM), silagem de sorgo (SS), cana-de-açúcar in natura (CN) e silagem de cana-de-açúcar (SC). As dietas foram formuladas fixando a quantidade de concentrado em 0,5% do peso corporal para silagens de milho e sorgo, 0,7% para cana-de-açúcar in natura e 1,0% para silagem de cana-de-açúcar. Os animais alimentados com dietas à base de silagens de milho e sorgo apresentaram maior ganho médio diário em relação aos alimentados com dietas contendo cana-de-açúcar in natura e silagem de cana-de-açúcar. O consumo e a digestibilidade de matéria seca (MS), matéria orgânica (MO) e energia digestível (ED) foram maiores para as novilhas alimentadas com dietas à base de silagens de milho e de sorgo. Houve maior consumo e digestibilidade de proteína bruta (PB) e fibra em detergente neutro (FDN) para as novilhas alimentadas à base de silagem de sorgo. Para carboidratos não-fibrosos (CNF), verificou-se maior consumo e digestibilidade nas novilhas alimentadas à base de silagem de milho. Não foi observado efeito sobre os parâmetros de altura de cernelha e comprimento corporal. Houve maior ganho de perímetro torácico para as novilhas alimentadas com dietas a base de silagens de milho e de sorgo. Conclui-se que dietas à base de silagens de milho ou sorgo proporcionam maiores desempenhos do que dietas à base de cana-de-açúcar in natura ou ensilada para as novilhas leiteiras.
177

An evaluation of the effects of two different inoculants on the quality of potato hash silage for grower pigs

Sylvester, Thomas Ronald January 2010 (has links)
Thesis (M. Tech.) -- Central University of Technology, Free State, 2010 / This study evaluated the effects of two bacterial inoculants on the fermentation quality and aerobic stability of ensiled potato hash (PH) and on digestibility, growth performance and carcass characteristics of growing pigs fed the ensiled PH. In the first experiment, 700 grams of PH, was mixed with 300g wheat bran (as is basis) and ensiled in 1.5 litre anaerobic jars. The mixture had a dry matter (DM) of 41.3 g/kg, 78.05 g/kg DM of water-soluble carbohydrates (WSC) and a pH of 6.87 at day 0 and was treated with Bonsilage forte, BF, a heterofermentative LAB, Lalsil Fresh lactobacillus bachneri, LFLB, a homofermentative LAB or without LAB inoculant (control). Triplicate samples per treatment were collected on days 0, 3, 10, 21 and 45 post-ensiling and analysed for DM, WSC, pH, lactic acid (LA), acetic acid (AA), butyric acid (BA), propionic acid (PA) and ammonia-N. On day 45, the silage was subjected to aerobic exposure for 5 days and CO2 production was measured. In the second and third experiments, potato hash-wheat bran mixtures of 7:3 ratio were produced and ensiled in 210 litre drums that were kept at a 250C environment. The second experiment involved an apparent nutrients digestibility study using 30 female (Large White x Landrace crossbred) pigs (30 2 kg live weight), which were selected and housed individually. A cross-over design was applied with two periods and 30 animals fed 10 diets. Three pigs were given one diet per period. The diets were: commercial feed (control); 20, 40, and 60% dietary inclusion of potato hash silage (untreated potato hash silage, UPHS; Lalsil Fresh treated potato hash silage, LFLBPHS, and Bonsilage forte treated potato hash silage, BFPHS). Each experimental period lasted for eleven days with seven days being for adaptation to each diet and four days for collection of faeces before crossing over to the next treatment. Pigs were fed twice per day at 8:00 and 15:00, with the daily allowance equally divided between the two meals. Faecal samples were weighed and 10% of the total collection was taken and kept in a freezer at -180C. Prior to chemical analysis, individual samples of faeces were thawed and pooled for pigs within periods. Water was made available at all times through drinking nipples. The third experiment was a pig growth study using sixty-four crossbred pigs (Large White x Landrace) consisting of 32 males and 32 females (30.4±2.3kg live weight). The pigs were randomly allocated to four diets in a 4 x 2 (treatment x sex) factorial experiment in a completely randomised design. The diets contained up to 40% potato hash silage (PHS) and were: control (commercial diet - no silage), UPHS, BFPHS and LFLBPHS. Each experimental unit consisted of two pigs and each treatment was replicated 8 times. Pigs were fed on one of the four diets until they reached a slaughtering weight of 60 kg. Warm carcass weights were determined immediately after slaughter. After an overnight chill storage at 4.30C, cold carcass weights were determined. Carcass length was taken on hanging carcasses by measuring from the pelvic bone to the first thoracic vertebra, using a measuring tape. Backfat thickness was also taken on cold carcass at P2 (45 mm from midsection) between the 3rd and 4th rib on the left side of the pigs. Drip loss was also calculated for hanging carcasses by determining the weight loss after the overnight chill. Results from experiment 1 showed that both inoculants (LFLB and BF) reduced (P<0.05) the silage pH while increasing the LA content of silage compared to the control. The concentrations of propionic acid, butyric acid and ammonia-N were not affected by inoculation. When exposed to air, BF and LFLB reduced (P<0.05) CO2 production compared to the control. Results of the second experiment showed that daily intakes of organic matter (OM), crude protein (CP), ether extract (EE), acid detergent fibre (ADF), neutral detergent fibre(NDF), and gross energy (GE) were different (P<0.05) between diets. There were no differences (P<0.05) in digestibility of DM, EE, and DE among the treatments. However, diets containing 60% PHS had lower (P<0.05) NDF and ADF digestibility compared to diets containing less PHS. Furthermore, pigs on the control diet had higher (P<0.05) final body weight, average daily gain (ADG) and better feed conversion ratio (FCR) compared to those fed on other diets. Results of the third experiment showed that, pigs that were fed the control diet had higher (P<0.05) slaughter weight than pigs that were fed on diets containing PHS. There were no differences (P>0.05) on warm and carcass weight between diets containing PHS. Control had higher (P<0.05) dressing percentage than the other treatments. Drip loss percentage, backfat thickness, gastrointestinal tract (GIT), lungs and heart did not differ (P<0.05) between treatments. The effects of gender was not significant within treatments on slaughter weight, warm and cold carcass weights, dressing percentage, carcass length, backfat thickness, drip loss, GIT, lungs and heart. There were no gender by diet interactions (P>0.05) on warm carcass weights, cold carcass weights, drip loss percentage, carcass length, backfat, intergastral, lungs and heart. However, gender by diet interaction (P<0.05) occured on slaughter weight and dressing percentage. It was concluded that, inoculation improved both the fermentation and aerobic stability of PHS. Furthermore, there was no advantage in using LAB inoculants in ensiling potato hash on the growth performance or meat characteristics of growing pigs. However, further work is needed to evaluate the effects of higher dietary inclusion levels (> 60 %) of PHS on pig growth and reproductive performance.
178

Fermentation, stability and degradability of whole-crop oat silage ensiled with a commercial inoculant

Pienaar, Johanni 03 1900 (has links)
Thesis (MScAgric (Animal Sciences))--Stellenbosch University, 2010. / ENGLISH ABSTRACT: South Africa is well-known for periodic dry periods and uncertain rainfall. Ensiling of crops is a method of preserving forage and ensures feed availability during periods when the supply of good quality forage is low. Cereal-based silages, especially in the Western Cape, South Africa, represent a significant proportion of feed consumed by ruminant animals, particularly high-producyion dairy cattle. However, farmers are still concerned about the technical challenges of ensiling cereal crops. Previous research done on lactic acid bacteria (LAB) inoculants used on cereal based silage has indicated a potential for improving silage fermentation, stability and degradability, thus enhancing feed conversion and production by ruminants. Two experiments were conducted to determine the effects of inoculating whole-crop oat silage with Lalsil® Cereal Lactobacilli (Lactobacillus buchneri (NCIMB 40788) and Pediococcus acidilactici (CNCM MA 18/5M)) LAB on (1) silage fermentation, (2) aerobic stability and (3) nutritional value of silage ensiled under a. micro-silos conditions and b. in a bunker under outdoor conditions of a Mediterranean summer. Oats (Avena sativa, cv SSH 405) were planted on 60 ha under dryland conditions at Elsenburg in the Western Cape province, South Africa. Whole-crop oats were harvested at the soft dough stage and length of the chopped material was 9 mm (Day of ensiling – Day 0). Chopped whole-crop oats were sampled, mixed thoroughly and divided into two portions. The Inoculant (Lalsil® Cereal) was applied to one portion to provide 5.79 x 109 colony forming units (CFU) of LAB per gram of fresh material. In the first experiment twenty - four glass silos (1.5 L glass jars) (WECK, GmbH u.Co., Wehr-Ofligen, W. Germany) were filled for each of the control and inoculant treatments. The glass silos were stored in a dark room in the laboratory at ambient temperature. Three glass silos were opened for each treatment on days 1, 2, 4, 8, 15, 30, 60 and 102 post-ensiling to determine fermentation dynamics. A parallel study was done with the same chopped whole-crop oats using the buried bag technique in a bunker silo. Whole-crop oats were ensiled in six net bags per treatment buried in a bunker filled with the same untreated whole crop oats. Bags, attached with nylon lines (3 m lengths) for easy retrieval were buried at 1m and 2 m depths in the same bunker. The net bags in the bunker were retrieved after 186 days of ensiling. Dry matter (DM), organic matter (OM), neutral detergent fibre (NDF), crude protein (CP), lactic acid levels, pH, water soluble carbohydrates (WSC) and in vitro organic matter degradability (IVOMD) for both studies were determined. Silage of both experiments was exposed to aerobic conditions for ten days to determine aerobic stability. It is concluded that the inoculant Lalsil® Cereal had the effect of reducing the rate of consumption of WSC during the anaerobic phase and aerobic exposure for both experiments. Silage spoilage due to yeasts and moulds was however more evident with the inoculated silage due the presence of sugars in the micro-silos experiment. / AFRIKAANSE OPSOMMING: Suid-Afrika is bekend vir droë periodes en wisselvallige reënval. Die inkuiling van gewasse is ‘n goeie manier om ruvoer te voorsien in tye van droogtes of tekorte. Kleingraan kuilvoer is veral bekend in die Wes-Kaap, Suid-Afrika en maak ‘n groot deel uit van die melkkoei se rantsoen. Landbouers is nog steeds bekommerd oor die tegniese aspekte wanneer dit kom by die inkuil van gewasse. Vorige navorsing het getoon dat die gebruik van ‘n melksuurbakteriese inokulant saam met die inkuiling van gewasse moontlik die potensiaal het om fermentasie, stabiliteit en degradering te verbeter en sodoende voeromset te verbeter. Twee eksperimente is uitgevoer om die effek van die inkuiling van hawerkuilvoer met Lalsil® Cereal Lactobacilli (Lactobacillus buchneri (NCIMB 40788) en Pediococcus acidilactici (CNCM MA 18/5M)) LAB te bepaal op (1) kuilvoer fermentasie, (2) aërobiese stabiliteit en (3) nutriëntwaarde van die kuilvoer ingekuil in a. mikrosilo’s en b. in ‘n bunker in die buitelug. Hawer (Avena sativa, cv SSH 405) is op 60 ha droë land geplant op Elsenburg in die Wes-Kaap, Suid-Afrika. Die hawer is ingekuil tydens die sagte deeg stadium en die gekapte materiaal was ongeveer 9 mm lank. Gekapte material was deeglik gemeng en in twee gedeel. Die inokulant (Lalsil® Cereal) is op die een gedeelte gesproei om 5.79 x 109 kolonie-vormende eenhede (KVE) melksuurbakterieë per gram vars materiaal te voorsien. Tydens die eerste eksperiment is 24 mikrosilo’s (1.5 L glas silo) (WECK, GmbH u.Co., Wehr-Ofligen, W. Duitsland) vir elke behandeling vol kuilvoer gemaak. Hierdie mikrosilo’s is gestoor in ‘n donker kamer teen kamertemperatuur. Drie mikrosilo’s is per behandeling oopgemaak op dag 1, 4, 8, 15, 30, 60 en 102 na inkuiling om die fermentasie-dinamika te bepaal. ‘n Parallelle studie is gedoen met dieselfde materiaal ingekuil in netsakke binne die bunker. Die materiaal was ingekuil in ses netsakke vir elke behandeling. Nylon toue (3 m) is aan die sakke vasgemaak om die uithaal daarvan op latere stadium te vergemaklik. Hierdie sakke is ingekuil op verskillende dieptes, 1 m en 2 m in dieselfde bunker. Die sakke is na 186 dae weer uitgehaal. Droë materiaal (DM), organiese materiaal (OM), neutraal bestande vesel (NBV), ruproteïen (RP), melksuurvlakke, pH, water oplosbare koolhidrate (WOK) en in vitro organiese materiaal verteerbaarheid (IVOMV) vir beide studies is bepaal. Kuilvoer van beide eksperimente is ook blootgestel aan aërobiese toestande vir 10 dae aan aërobiese toestande blootgestel om aërobiese stabiliteit te bepaal. Daar is bepaal dat die inokulant Lalsil® Cereal het die tempo van WOK verbruik verminder gedurende die anaërobies fase sowel as die aërobiese fase vir beide eksperimente. Kuilvoer wat bederf het as gevolg van giste en swamme was meer sigbaar by die inokulant behandelde kuilvoer as gevolg van die teenwoordigheid van suikers in die mikrosilo’s. (Sleutelwoorde: hawerkuilvoer, inokulant, mikrosilo’s, water oplosbare koolhidrate (WOK), in vitro organiese materiaal verteerbaarheid (IVOMV))
179

Untersuchungen zur Unterbindung von Buttersäuregärung und Clostridienaktivität in Silagen aus nitratarmen Grünfutter

Iv, Polip 19 July 2001 (has links)
Ziel der vorliegenden Arbeit war zum einen die Ermittlung des im Grünfutter notwen-digen Mindest-Nitratgehaltes zur Erzielung buttersäurefreier Silagen, wobei TS-Gehalt und Z/PK-Quotient des Ausgangsmaterials sowie dessen Belastungsgrad mit Clostridiensporen berücksichtigt wurden. Dazu wurden zwei mehrfaktorielle Laborsi-lierversuche durchgeführt, bei denen eine Variationsreihe des Nitratgehaltes (0,01...0,3 % NO3-N in TS) mit Variationsreihen des TS-Gehaltes (ca. 14...40 %) und des Z/PK-Quotienten (1,5...3,1) systematisch kombiniert wurden. Jede Wertekombi-nation wurde sowohl mit sauber geerntetem Grünfutter als auch mit Clostridienspo-ren kontaminiertem Grünfutter geprüft. Die Silagen wurden nach 180 Tagen Lage-rungsdauer untersucht. Zum anderen wurde die Dynamik der Clostridienentwicklung im Gärungsverlauf in Abhängigkeit von TS-Gehalt, Säuerungsintensität und Nitratge-halt geprüft. Jede Stufe des TS-Gehaltes (20, 30, 40 und 50 %) wurde mit Zusätzen von Nitrat, Milchsäurebakterien (MSB) bzw. MSB + Glucose und MSB + Nitrat ange-setzt. Das Ausgangsmaterial (Dac. glomerata, nitratfrei) war durchgehend mit Clostridiensporen kontaminiert. Die Untersuchung der Silagen erfolgte 3, 7, 14, 28, 56 und 180 Tage nach dem Ansatz. Der Konservierungserfolg bei der Silierung hängt nicht nur vom TS-Gehalt und Z/PK-Quotienten sondern auch vom Nitratgehalt und Clostridiensporenbesatz des Aus-gangsmaterials ab. Bei sehr niedrigem Nitratgehalt des Grünfutters liegt ein erhöhtes Risiko für die Entstehung von Buttersäure in der Silage vor, auch bei dem als leicht vergärbar geltendem Grünfutter (VK > 45) und auch dann, wenn es im sauber geern-tetem Zustand einsiliert worden ist. Bei weiter erhöhten VK-Werten, > 45 (durch Er-höhung des TS-Gehaltes und/oder Z/PK-Quotienten), wird die Höhe der Buttersäure-gehalte zwar eingeschränkt. Zur sicheren Ausschaltung von Buttersäuregärung ist jedoch auch hier ein gewisser Nitratgehalt notwendig. Bei der Silierung nitratfrei-en/nitratarmen Grünfutters nimmt das Fehlgärungsrisiko mit dem Belastungsgrad an Clostridiensporen zu. Der notwendige Mindest-Nitratgehalt (MNG) hängt sowohl vom VK-Wert als auch vom Kontaminationsgrad des Grünfutters mit Clostridiensporen ab. Er ist um so niedriger, je höher der VK-Wert und geringer der Kontaminationsgrad ist, und umgekehrt. (MNG (% NO3-N in TS) für sporenarmes Grünfutter = 0,24 - 0,0035 . VK MNG (% NO3-N in TS) für sporenreiches Grünfutter = 0,20 - 0,0021 . VK) Hohe Clostridiensporengehalte lagen vor allem in buttersäurehaltigen Silagen vor und insbesondere dann, wenn das Grünfutter sehr geringe Nitratgehalte aufwies. Zwischen der Höhe der Buttersäuregehalte und dem Clostridiensporengehalt besteht jedoch kein direkter Zusammenhang. Erhöhung des TS-Gehaltes bewirkt eine Ein-schränkung der Clostridienentwicklung. Ein Rückgang des Sporengehaltes im Ver-gleich zum Ausgangsmaterial (nitratfrei) lag aber erst bei einem TS-Gehalt von etwa 50 % vor. Durch Zusätze von MSB sowie MSB + Glucose konnte die Milchsäuregä-rung deutlich intensiviert werden. Ein sehr geringer pH-Wert war schon am 3. oder 7. Lagerungstag erreicht. Buttersäuregärung war aber erst bei TS-Gehalten > 40 % ausgeschaltet. Eine Einschränkung der Sporenbildung lag ebenfalls erst bei TS-Gehalten über 40 % vor. Bei Nitratzusatz blieben die Silagen aller TS-Stufen bis zur Auslagerung buttersäurefrei. Die Sporengehalte gingen in allen TS-Stufen während des Gärungsverlaufes kontinuierlich zurück. Bei steigenden TS-Gehalten war der Rückgang der Sporengehalte verlangsamt. Durch die Kombination von MSB und Nit-rat konnte nicht nur ein sicherer Erfolg bei der Unterbindung von Buttersäurebildung und Laktatabbau sondern auch eine starke Verminderung der Sporengehalte erreicht werden. / The first aim of this work was to determine the minimum content of nitrate (MCN) which is required to get silage free of butyric acid. For it, two multi-factorial experi-ments with orchardgrass were carried out under laboratory condition. In this experi-ments, nitrate content (0.01 ... 0.3 % N in DM) was systematically combined with staggered levels of the dry matter (DM) content (14 ... 40 %) and of the ratio of water-soluble carbohydrate to buffering capacity (WSC/BC: 1.5 ... 3.1). All variants were tested with forage without or with addition of clostridial spores. The silages were ana-lysed after 180 days of incubation. The second aim of this study was to explain the dynamic of clostridial development during ensilage, depending on DM content, intensity of lactic acid formation, and ni-trate content. orchardgrass (free of nitrate) with 4 levels of DM (20, 30, 40, and 50 %) was firstly contaminated with clostridial spores about 104 / g FM. Then it was ensi-laged with following treatments: without additives, with inoculation of lactic acid bac-teria (LAB) alone or in combination with 2 % Glucose in FM (LAB+G), with nitrate addition (0.1 and 0.15 % N in DM), and with LAB plus nitrate 0.1 % N in DM. The si-lages were analysed 3, 7, 14, 28, 56, and 180 days after ensiling. Results showed that silage quality not only depends on DM content and ratio of WSC to BC, but also depends on nitrate content and extent of clostridial spores in forage. With an extremely low content of nitrate a high risk of butyric acid formation is given in silages, even if the ensiling material had a high ensilability (FC ³ 45) and a very low content of clostridial spores. The butyric acid concentration decreased with in-creasing DM content from 14 to 40 % or with increasing WSC/BC-ratio. But to get the silages free of butyric acid, a certain amount of nitrate was required. By adding clos-tridial spores in fodder the risk of butyric acid formation was increased, especially in case of material lacking in nitrate. The value of MCN depends on ensilability of the forage, as measured by DM-content and WSC/BC-ratio or by fermentability coefficient (FC) = DM+8WCS/BC, as well as depends on content of clostridial spores in the material used. The higher the FC-value and the lower the spores content is, the less nitrate is required to get silage free of butyric acid. MNC (% N in DM) for very low contaminated forage = 0.24 - 0.0035.FC MNC (% N in DM) for high contaminated forage = 0.20 - 0.021.FC High content of clostridial spores was especially found in silages containing butyric acid, which were made from forage with very low nitrate content (£ 0.02 % N in DM). But a strong relationship was not found between butyric acid and spores content. By increasing DM content the development of clostridia during ensiling was limited. A continuous decrease of spores content, in comparison with the forage before ensiled, was observed at first by increasing DM content to 50 %. By inoculation with LAB or LAB+G the lactic acid formation was strongly stimulated. A very low pH was reached 3 or 7 days after ensiling. But the butyric acid formation could be firstly prevented by increasing DM content to over 40 %. For all levels of DM, by nitrate addition the silages remained no butyric acid during the whole period of incubation. The concentration of clostridial spores decreased continuously during ensilage. This decrease was slower with increasing DM content . By combination of LAB with nitrate a reliable prevention of butyric acid formation and a fast decrease in spores concentration were reached.
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Ablauf und Beeinflussungsmöglichkeiten der Proteolyse während der Silierung von Weidelgras und Luzerne

Roscher, Simone 22 February 2018 (has links)
Tannine gehören zu den phenolhaltigen Verbindungen und galten in der Tierernährung bisher als sekundäre unerwünschte Pflanzeninhaltsstoffe. Sie werden in der Regel in zwei Hauptgruppen eingeteilt: kondensierte und hydrolisierbare Tannine. Im Mittelpunkt der vorliegenden Untersuchungen stand die Quantifizierung der Reduzierung der Proteolyse während der Silierung in Folge der Zulage von tanninhaltigen Pflanzenextrakten unterschiedlicher Herkunft zum Siliergut. Zu diesem Zweck wurden zunächst in Silierversuchen zwei tanninhaltige Pflanzenextrakte unterschiedlicher botanischer Herkunft (Mimosa und Quebracho) alleine sowie in Kombination mit Silierzusätzen dem Ausgangsmaterial am Beispiel Weidelgras (Lolium perenne L.) zugesetzt. Folgend wurden die Effekte unterschiedlicher Konzentrationen der beiden tanninhaltigen Pflanzenextrakte sowie die Effekte bei unterschiedlichen TM-Gehalten des Siliergutes auf den Umfang der Proteolyse am Beispiel der Luzerne (Medicago sativa L.) geprüft. In den Versuchen konnte gezeigt werden, dass die Tannine einen deutlichen Einfluss auf die Proteolyse während der Silierung insbesondere in den ersten Tagen hatten. Die Beurteilung der Effekte der Zulage von tanninhaltigen Pflanzenextrakten basierte unter anderem auf Veränderungen der Parameter der Rohproteinfraktionierung nach dem Cornell Net Carbohydrate and Protein System (CNCPS). Durch den Zusatz von tanninhaltigen Pflanzenextrakten konnte der Abbau von schwer- und mittellöslichen Rohproteinfraktionen (Fraktionen B1-B3) zur leichtlöslichen Rohproteinfraktion (Fraktion A) signifikant minimiert werden, parallel stieg der Gehalt der pansenstabilen Rohproteinfraktionen. Die Effekte unterschiedlicher TM-Gehalte in den Silierversuchen mit Luzerne (Medicago sativa L.) zeigten, dass die eingesetzten tanninhaltigen Pflanzenextrakte unabhängig von ihrer botanischen Zusammensetzung in ihrer Wirkung umso höher waren je geringer der TM-Gehalt war. / Tannins belong to phenol compounds and have traditionally been classified as antinutritive substances in animal nutrition. Tannins are usually divided into two groups: hydrolyzed and condensed tannins. The present study focused on reducing proteolysis during ensilage by supplementing tannin extracts from different botanical sources. Ensilage studies were carried out with Lolium perenne dominated forage and two different tanniniferous extracts (Mimosa and Quebracho) alone as well as in combination with silage additives. In a second study, the effects of different tannin concentrations and two different dry matter levels on proteolysis during ensilage were tested with alfalfa (Medicago sativa L.). The results show that tannin extracts definitely reduce proteolysis during the first days of ensilage. The protein fractionation of the Cornell Net Carbohydrate and Protein System (CNCPS) was used as indicator. Degradations from slightly soluble (B1 – B3) to easily soluble (A) fractions were significantly reduced by the addition of tannin extracts. At the same time, the level of rumen undegradable true protein was increased. The alfalfa study used different dry matter levels showing that by supplementing tannin extracts the wetter the silage was, the clearer the effect on reducing proteolysis.

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