During the last few years, many Danish dairy farmers have expressed increasing concerns regarding a group of cows, which we have chosen to term ‘loser cows’. Until now, a loser cow has not been described scientifically. We defined a loser cow on the basis of a clinical examination of the cow. A total of 15,151 clinical examinations were made on 6,451 individual cows from 39 randomly selected, large Danish dairy herds with loose-housing systems using a clinical protocol. Scores for the clinical signs lameness, body condition, hock lesions, other cutaneous lesions, vaginal discharge, condition of hair coat and general condition were converted into a loser cow score. Cows with a loser cow score of 8 or more were classified as loser cows. The overall prevalence of loser cows was 2.15%, 4.50% and 2.98% during the first, second and third round of herd visits, respectively.
The associations between the loser cow state and milk production, mortality, morbidity, culling and workload for the farmer were evaluated using data from herd visits and from the Danish Cattle Database and a number of different statistical techniques. It was concluded that the loser cow state has significant negative consequences for both the farmer and the cow. On average, loser cows yielded 0.61 to 2.24 kg energy corrected milk less per day than non-loser cows depending on parity. Hazard ratio for death or euthanasia was 5.69 for loser cows compared to non-loser cows. Incidence rate ratio for disease treatments was 0.69 for non-loser cows compared to loser cows. Loser cows were often culled in an ‘unfavourable’ way and generally caused extra workload for the farmer.
A simplified version of the loser cow score was evaluated and is recommended for future research and use in practice. 相似文献
The authors determine the index system and the index weight of capability of real estate by applying Delphi method and AHP method, and found the fuzzy comprehensive evaluation model of capability of real estate. They creates the model of capability Vs. price based on value engineering theory. The authors analysis detailedly deciding method of capability Vs. price of real estate combined with a practice example and application. The method adapts to a house as well as the type of the house. The method resolves the problem which capability Vs. price of real estate was only described by qualitatively for ages, which supplies theory basis to developer and consumer. 相似文献
For raveling out the main shortage of tendering which is the reasonable sector is unreasonable of making the bid evaluation uncertain. In order to eliminate subjective factor, this paper quantificationally analyses the price in bidding and establishes the sector selecting bid model based on the sector estimate idea, which tries to provide a new method and academic basic for determining the reasonable sector. Finally, the article gives an example to prove that the model is feasible and effective and it tries to ensure the bidding assessment public, equitable and just. 相似文献
This paper has applied the var cost to the theory of spot price.An augmented Lagrange method is employed to develop the exact model of spot price of active power and reactive power,and the physical means of Lagrange multipliers are explained.The numerical examples are given to demonstrate the validity of the proposed model. 相似文献
We prove a Donsker type approximation theorem for the fractional Brownian motion in the case of the Hurst index greater than one half. With this approximation we construct an elementary market model that converges weakly to the fractional analogue of the Black Scholes model. We show that there exist arbitrage opportunities in this model. 相似文献
Economics.Through sampling investigation and analysis on inhabitant domestic tap water consumption situation,it is given that economic factors are the main factors influence inhatitant's water consumption.The functional relations among inhabitant's income and water consumption,water price and consumption are given. The tap water's income elasticity of demand and price elasticity of demand is analyzed, along with the fluctuating range month by month of inhabitant's water consumption.Finally ,this paper offers the reference data for planning the ability of water supply and making policies of ladder water prices. 相似文献
In 1995, Padmanabhan and Vrat presented inventory models for deteriorating items with a constant selling price and stock dependent selling rate . Based on the result, in 2000, Kun-Jen Chung, Peter Chu and Shaw-Ping Lan devoloped the necessary and sufficient conditions of the existence and uniqueness of the optimal solutions of the profit per unit time functions without backlogging and with complete backlogging. Actually, the selling price need not be constant, it may be variable . This paper puts forward an EOQ model when the selling price is variable without backlogging, discusses the existence and uniqueness of optimum solution. The example is provided to illustrate the model. The theoretical evidence is provided for the inventory system to make management decision. 相似文献