After parturition the energy demand for milk production is greater then the energy provided from the diet. The cow mobilises therefore body tissues to compensate for the energy loss. Live weight and body condition scores decreases as a consequence of the mobilisation. The aim of this study was to analyse the relationship between body condition score, live weight and subcutaneous fat depth measured by ultrasound and the changes during the lactation. Possible differences between Swedish Holstein (SLB) and Swedish Red and White Cattle (SRB) were also investigated.

Milk fat is an important feature in many different milk products and other foodstuffs and it is often crucial for the dairy plants that the milk fat is stable for different manufacturing processes. Lipolysis is the enzymatic degradation of fat and is the one of the causes for an elevated amount of free fatty acids (FFA) in milk. Further, the change in fatty acid (FA) composition in milk can affect the stability of the product and also the manufacturing process. Both internal and external factors, at farm level or at the dairy plants can affect both FA composition and content of FFA. Milking frequency (MF=number of milkings per cow and day) and the composition of feed are two examples of factors generally performed at farm level. The objective of the present study was to evaluate how FA composition of milk and amount of FFA are influenced by two different ingredients supplemented to concentrate.

Nötcenter Viken is a Swedish nucleus herd for dairy cattle. The goal for the farm is to select suitable mothers for the next top generation of bulls. Today the selection for udder health is based on a pedigree index and phenotype data. The pedigree index is based on the cow?s father and grandfathers breeding values.

Mastitis is an important disease in dairy cattle. It is very costly for the farmers and affects a large number of animals. Few studies have been made investigating the outcome of treatment for acute clinical mastitis under Swedish conditions, and it can be problematic to use the results in foreign studies since both the microbial flora as well as treatments may be different from the situation in Sweden. In this project we have investigated data on clinical mastitis and antibiotic treatment in the dairy herd at Jällaskolan, Uppsala based on recordings during the last ten years. The material includes both Swedish Red (SRB) and Swedish Holstein (SLB) breeds, which have been kept at the farm under similar conditions.

Concentration of protein in bovine milk is one of the most significant milk quality parameters, to a large extent determining the price for milk to the producer. Mastitis is a common disease among dairy cows, negatively affecting not only milk yield but also milk protein composition. Milk from mastitic cows tends to have lower cheese yield, negatively affected processability properties and sensory quality, due to changed protein quality and composition. Poorer milk protein quality would have an economically negative impact on dairy industry. Only few studies have investigated the short term effects of mastitis on milk protein composition.

Efterfrågan på marmorerat kött har ökat i Sverige under de senaste åren. Marmorering är insprängt fett i muskulaturen, intramuskulärt fett, vilket anses vara en god indikator för köttets sensoriska kvalitet. Det insprängda fettet lyfter fram köttets smakämnen, fettet bidrar även till att köttet upplevs som saftigare. Det insprängda fettet separera muskelsegmenten, vilket ökar köttets mörhet. Utvecklingen av intramuskulärt fett är relaterat till faktorer som genotyp, ras, kön, ålder, muskeltyp samt tillväxthastighet av muskel- och fettvävnad. Även utfodringens intensitet påverkar andelen intramuskulärt fett. För att tillgodose konsumenternas efterfrågan på marmorerat nötkött har den svenska köttbranschen gemensamt arbetat fram en nationell standard för klassificering av marmorering hos nötslaktkroppar.