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29 Uppsatser om Urea - Sida 2 av 2
Genetiska och epigenetiska samband mellan näringsförsörjning och fertilitet hos mjölkkor
The dairy cow?s ability to resume estrus after calving and to conceive is affected by their metabolic status after calving. For high yielding cows there is a high risk that the feed intake will not be sufficient to cope with the increased energy demands after calving, and the cow will end up in a state of negative energy balance. Energy balance can be measured in various ways, for example by body condition score or by plasma concentration of several metabolic hormones and metabolites. After calving, endocrine pathways stimulate tissue mobilization; insulin signaling is blocked, the concentration of insulin-like growth factor-1(IGF-1) and leptin decreases, and the concentration of growth hormone (GH) increases.
Optimering av ureainsprutning för SCR katalysator
Kommande emissionskrav inom fordonsindustrin för utsläpp av kväveoxider, partiklar, kolväten och koldioxid innebär att tillverkarna måste förbättra renheten på avgaserna som släpps ut. Ett sätt att göra detta är efterbehandling av avgaserna med SCR-system. Ett SCR-system fungerar på det sättet att man sprutar in Urea i avgaserna vilket omvandlas till ammoniak som i den efterföljande katalysatorn reagerar med kväveoxiderna och bildar oreglerade ämnen. För att få hög omvandlingsgrad av kväveoxiderna i katalysatorn är det viktigt att man har en jämn fördelning av ammoniak i avgaserna samt att all Urea har omvandlats till ammoniak. Denna studie har gjorts på ett befintligt SCR-system hos Scania CV AB.
Drankgivans och vallfoderkvaliténs effekt på konsumtion och produktion hos mjölkkor :
The coproduct, dried distillers grains + solubles (DDGS) from ethanol production based on wheat contains much rumen degradable protein and fiber with low digestibility. To compliment this quality in an effective way a grass silage low in protein and much digestible fiber is needed.
The aim of the study was to investigate the effects of adjusting the crude-protein concentration and fiber quality of the silage when feeding DDGS and of varying the
inclusion level of DDGS, when feeding the adjusted grass silage, on intake, milk yield and composition, faecal traits and feed efficiency.
Four different total mixed rations were compared. The normal grass-clover silage had a crude protein content of 17,8 % and an NDF content of 46,2 % of dry matter. The adapted grass silage had a crude protein content of 14,6 % and an NDF content of 52,9 % of dry matter. The diets were formulated to have similar nutritional content except for A + 4 which had a higher content of rumen degradable crude protein and a lower concentration of NDF.
Förekomst av Helicobacter spp. hos hund : samband med hepatit/pankreatit?
To date, the genus Helicobacter consist of 26 different species and even more species are yet to be characterized. Helicobacter has been detected in connection with diseases in the liver and pancreas in humans and animals.
Helicobacter spp. are gram negative, curved, S-shaped or spiral shaped bacteria. They are microaerophilic and have flagella that make them motile. Helicobacter, present in the gastric mucosa neutralize the gastric acid through production of Urease that hydrolyses Urea to ammonia and bicarbonate.
Mjölkningsfrekvensens påverkan på mjölkproteinets sammansättning och kvalitet :
In modern dairy production the milking frequency is increased in some herds due to introducing of automatic milking systems or the farmers decision to milk high producing dairy cows more than two times a day. With more frequent milkings the milk yield increases while the content of fat and protein decreases. However, how the composition of protein is influenced is not fully evaluated. The purpose of this study was therefore to see if a higher milking frequency had any impact on the milk production and especially on the protein composition.
This study was conducted as a half udder experiment.
Fertility before and after installation of Herd Navigator?
The fertility of dairy cows is of great importance in order to maintain high production. The decline in fertility of dairy cows the latest decades can have several explanations. The large emphasis on high yielding cows and the negative genetic correlation between milk production and fertility traits could be one of the main factors for impaired fertility. To find heats and inseminate the cow at the right time is crucial to receive high conception rate. Delaval has, in corporation with FOSS, developed Herd Navigator which is a management program that measure four biological parameters in the milk; progesterone, betahydroxybutyrate, lactate dehydrogenase and Urea.
Kan mjölkkors utnyttjande av vallprotein bli bättre? : utfodringsstrategier och konserveringsmetoder
The purpose with this literature study was to investigate the possibilities for improvement of forage protein in dairy cows with focus on feeding strategies and conservation of forage protein. The utilization of forage protein in dairy cows is often not that efficient as it could be. The feed crude protein consists of both true proteins and non protein nitrogen. The digestion of proteins in the rumen depends on the protein degradation rate and the ability of the microbes to synthesize microbial protein. The microbes need a balance between carbohydrates that provide them with energy and proteins that are degradable in the rumen.
Effekten av toxiciteten hos ek för get, får och nötkreatur
Ekförgiftning orsakas av att djuren äter antingen ekollon eller eklöv. Förgiftningssymtomen och skadorna orsakas av en substans som kallas tanniner. Tanniner delas in i två huvudsakliga grupper, de kondenserade och de hydrolyserbara. Det är främst de hydrolyserbara tanninerna som är skadliga detta beror på att de lätt påverkas av de enzymatiska processerna i våmmen hos idisslare, och de produkter som bildas vid dessa processer är vattenlösliga och tar sig lätt ut i vävnaderna. De skador som främst ses vid ekförgiftning hos idisslare är ulcus i gastrointestinalkanalen, akut tubulär nekros och leverskador.
Värdering av kvävet i organiska gödselmedel :
Within agriculture it is important to optimize the use of nitrogen, not only from an economic point of view but also to minimize damage to the environment. This can sometimes be difficult, especially within organic farming. Organic farmers are using increasing amounts of waste products from the food industry to cover their nitrogen needs. These different organic fertilizers release nitrogen at different rates and under specific soil conditions. Because of this, it would be beneficial to have a standardized method to measure the amount and rate of nitrogen mineralization from organic fertilizers.
This project contributes to this knowledge by investigating whether relatively simple and
repeatable laboratory methods can be used to estimate the nitrogen fertilizer value of organic fertilizers.
Riskfaktorer för Staphylococcus aureus i mjölk och på has hos mjölkkor :
Mastitis is the most common disease of dairy cows. Mastitis can be painful for the dairy cow and causes economical losses for the farmer. These losses are due to decreased milk production, more working hours for the farmer, treatment costs and possible costs due to culling of the cow. The udder inflammation, mastitis, is often caused by bacteria infection. One of the most common bacteria found to cause mastitis in Sweden is Staphylococcus aureus (S.
Renala biverkningar orsakade av NSAID hos hund
Icke steroida antiinflammatoriska läkemedel (non steroidal anti-inflammatory drugs, NSAIDs) är en stor grupp läkemedel som har antiinflammatoriska, smärtstillande och febernedsättande effekter. Verkningsmekanism är att de hämmar enzymet cyklooxygenas (COX) vilket är det första enzym som omvandlar arakidonsyra till bland annat prostaglandiner (PG). Det finns flera isozymer av COX, varav COX-1 och COX-2 är de vanligaste målenzymen för NSAIDs. PG är involverade i flertalet viktiga processer i kroppen exempelvis smärta, feber och inflammation. NSAIDs kan grovt delas in i två grupper, traditionella icke-selektiva substanser som hämmar både COX-1 och COX-2 (oftast är substanserna mer selektiva för COX-1) samt coxiber som är selektiva för COX-2.
Hur kan blöt vetedrank lagras, hanteras och utfodras till mjölkkor? :
Distillers? grain is a by-product of ethanol production. Corn, wheat and barley are the grains
that are generally used in the distillery process. Distillers? grain is rich in protein and
phosphorus.
Peas as feed for dairy cows
AbstractAn approaching overproduction of cereals and a future uncertain supply of non genetic modified vegetable protein feedstuffs have increased the interest in an expansion of the domestic production of protein feedstuffs in Norway. Besides rapeseed (Brassica campestris), peas (Pisum sativum) may be the most suitable crop for this purpose. Peas are characterized by having a relatively high content of crude protein, ranging between 20-26%, a high content of starch, 42-51%, and a low content of fat. In general, the energy value for peas is higher than for barley but lower than for rapeseed and soybean meal.Pea protein consists of albumins and globulins to 85-100%, which leads to the fact that a large part of the pea protein is soluble and degradable in the rumen. Starch in peas is on the other hand to a large extent resistant to rumen degradation compared to starch from other starch rich feedstuffs.
Tillskott av linfrö till foderstater för mjölkkor : påverkan på näringstillförseln och mjölkens fettsyra-sammansättning hos 5 sydsvenska mjölkkobesättningar
Två viktiga fettsyror som människan inte själv kan bilda är ?-linolensyra (C18:3) och linolsyra (C18:2) vilka är en omega-3 respektive en omega-6 fettsyra. Ett balanserat förhållande mellan dessa fettsyror har visat sig vara viktigt för den mänskliga hälsan men idag är intaget av omega-3 lägre i kosten på grund av att den ingår i färre produkter än de med omega-6. Det lägre intaget av omega-3 antas resultera i att vi lättare drabbas av bland annat hjärt- och kärlsjukdomar, övervikt och depression. En produkt som skulle kunna jämna ut kvoten mellan omega-3 och omega-6 är linfrö, vilken innehåller 58 % C18:3 och 14 % C18:2.