Effect of various degrees of dystocia on the productivity of dairy cows during the current lactation.

Titelblatt Inhaltsverzeichnis Verzeichnis der verwendeten Abkürzungen Einleitung Literaturübersicht Material und Methoden Statistik Ergebnisse Diskussion Schlussfolgerungen Zusammenfassung Summary Literaturverzeichnis Anhang Lebenslauf Danksagung SelbständigkeitserklärungIn dieser Studie wurde der Einfluss,den verschiedene Schweregrade von Geburtshilfen bei Kühen auf die folgende Laktation hatten betrachtet. Es wurden retrospektiv Daten zu 261 Geburten, an denen eine tierärztliche Geburtshilfe geleistet worden war, in drei Gruppen eingeteilt: mittlere Geburtshilfe (MG), schwere Geburtshilfe (SG) und Kaiserschnitt (KS). Zu jeder Schwergeburt wurde ein Kontrolltier ausgewählt, das ohne tierärztliche Hilfe im selben Zeitraum gekalbt hatte und im selben Alter, in derselben Laktation war und derselben Rasse angehörte. Studien und Kontrolltiere wurden hinsichtlich Milchleistung, Milchinhaltsstoffe, Fruchtbarkeit und Abgangsraten von Kuh und Kalb untersucht. MG hatte nur geringe Auswirkungen auf die Milchleistung, Fruchtbarkeit und die Abgangsrate der Kühe. Verglichen mit den Kontrolltieren gingen mehr SG (28.1 vs. 25.8%) und KS (30.3 vs. 15.8%) ab. Bis zum 200. Laktationstag waren weniger Tiere tragend in der SG Gruppe (48.3 vs. 61.8%) und in der KS Gruppe (48.7 vs. 69.7%). Der Unterschied war nur für die KS Tiere signifikant. Die SG zeigte keinen Einfluss auf die Milchleistung, während die KS tiere eine signifikant niedrigere Milchleistung in den ersten 5 Kontrollmonaten als ihre Kontrolltiere aufwiesen. Im Vergleich zu der Kontrolltieren steigen die Kosten mit der Schwere der Geburtshilfe an (MG 58.86, SG 130.51, KS 236.61 / Tier).It was the objective of this study to analyse the effect of various degrees of dystocia on production, survival and to estimate the economic consequences. 261 calvings that were attended by a veterinarian were classified into three groups: mild dystocia (MD), severe dystocia (SD) and caesarean section(CS). To every case of dystocia was a control chosen, that had calved without veterinary help within the same month, was of same age, breed and parity. Cases and controls were compared concerning their culling risk, probability and time of conception, milk production and calf survival. MD had small effects on production,dam survival and fertility. Compared to controls, more SD (28.1 vs. 25.8%)and CS cows (30.3 vs. 15.8%) were culled and less cows conceived until 200 days in milk (SD: 48.3 vs. 61.8; CS: 48.7 vs. 69.7%). The Difference was only significant for CS cows. There was no obvious effects of SD on test day milk production while CS cows had a significantly lower milk production than their controls during the first 5 month of lactation. The proportion of stillbirth was sinificantly higher in cows with dystocia compared to their controls. The difference was significantly lower than in CS cows than in the other two groups. Economic losses compared to controls associated with dystocia increased with the degree of dystocia (MD 58.86; DS 130.51; CS 236.61 /cow)

Oh, RER'ly? Effects of Real Exchange Rate Misalignments on Economic Modernization

The role of the real exchange rate in an economy’s modernization process is an ambiguous matter and is not essential in the canonical models of neo-classical growth theory. This thesis tries to determine the role of the real exchange rate in a modernization process for Chile, Brazil and the Republic of Korea by applying the theory of a dual-sector approach to economic development by Lewis. By estimating individual equilibrium real exchange rates from 1970-2007, the methodology differ from recent literature on the subject which has focused on non-desirable homogenous assumptions between countries for estimating equilibrium real exchange rates. The results indicate that undervaluation fosters reallocation towards the modern sector of the economy, whereas overvaluation hampers the reallocation. No significant results could however be determined for the Republic of Korea

Adaptive Mixture Methods Based on Bregman Divergences

We investigate adaptive mixture methods that linearly combine outputs of $m$ constituent filters running in parallel to model a desired signal. We use "Bregman divergences" and obtain certain multiplicative updates to train the linear combination weights under an affine constraint or without any constraints. We use unnormalized relative entropy and relative entropy to define two different Bregman divergences that produce an unnormalized exponentiated gradient update and a normalized exponentiated gradient update on the mixture weights, respectively. We then carry out the mean and the mean-square transient analysis of these adaptive algorithms when they are used to combine outputs of $m$ constituent filters. We illustrate the accuracy of our results and demonstrate the effectiveness of these updates for sparse mixture systems.Comment: Submitted to Digital Signal Processing, Elsevier; IEEE.or