Search

The cost of feed contributes largely to the cost of pig production and energy represents the largest part of this cost. An appropriate assessment of the energy value of feed ingredients and diets is therefore very important in feed formulation. Likewise, it is important to understand and to quantify how an animal uses its dietary energy, which is often referred to as the energy requirement. To be meaningful, energy values and energy requirements must "talk the same language". For example, in a net energy (NE) system, the marginal efficiencies with which nutrients are used are attributed to the NE value of the ingredients or the diet. Consequently, these efficiencies are no longer accounted for in the NE requirement. In an ME system, only the material energy losses are accounted for in the ME value of an ingredient and the efficiency with which the energy is used is accounted for in the energy requirement as the cost of energy retention. The choice of an energy system has an important impact on the relative energy values of different feed ingredients and thus on feed formulation. Compared to starch, feed ingredients rich in fat have a higher NE value (compared to an ME value), while protein and fiber-rich ingredients have a lower NE value. Animal performance is better related to the NE intake than to the ME or DE intake and the NE system is therefore the preferred system for feed formulation in many countries. Although a NE system accounts for differences in energy efficiency among nutrients, a large part of the variation in NE values among feed ingredients originates from variation in energy digestibility. Also, the energy digestibility of a given ingredient typically increases with increasing body weight of the animal. This means that the DE value of a feed ingredient is not a property of the diet, but results from the interaction between the animal and its diet. Interactions between the diet and the animal also occur at the metabolic level. The fact that nutrients can be used for difference purposes (e.g., energy retained as protein or lipid, ATP production) has led to proposals to further refine the NE system. It is our belief that a further refinement of an NE systems is useful only if it is also accounts for interactions between the animal and its nutrients, thereby abandoning the very concept of additivity on which feed formulation is based. [ABSTRACT FROM AUTHOR]

Using accurate nutrient values for ingredients is of vital importance for efficient diet formulation. The net energy (NE) system accounts for the real available amount of feedstuff energy for body maintenance and production as it considers energy dissipated as heat increment. The NE content of diets for pigs and broilers has been estimated from their nutrient contents. However, such estimates have not been made specifically for laying hens. This study reports the development of equations to predict NE for laying hens based on the chemical composition of 16 different diets meeting minimum nutrient specifications but varying in nutrient composition. Heat production and energy metabolism were measured in layers ranging from 32 to 62 weeks of age in closed-circuit calorimetry chambers with 8 replicates per diet in a randomized design. Each replicate consisted of a chamber with 3 layers that were adapted for 4 D to diets and chambers prior to measurement. The measurements included feed intake, metabolizable energy (ME) content, nitrogen balance, egg production, gas exchange, heat production, energy efficiency, and energy partition for a 3-D period. The average AME/GE and NE/AME ratios of the 16 diets were 77 and 74%, respectively. The latter ratio increased with energy efficiency (EE) content and decreased with CP content of diets. The results indicate that diet NE content can be predicted from AME, CP, and EE contents and the NE/AME ratio varied positively with EE and negatively with CP. A validation experiment with 2 diets fed to layers in calorimetry chambers confirmed the estimation from NE prediction equations. In conclusion, NE of diets can be predicted in laying hens from equations based on AME and CP and EE contents in laying hens being similar to those reported in broilers. [ABSTRACT FROM AUTHOR]

The article presents a study on the analgesia after caesarean section. It mentions the suggested standard by the Royal College of Anaesthetists in Great Britain that over 90% women after caesarean section after birth delivery should have a worse pain score of < 3 on the Visual Analogue Score 0-10. Researchers are dismayed of their audit results from their audit that failed to meet the standard. Moreover, they also found out that they are not alone who failed to meet the target.

A class of compounds which are byproducts of the resin manufacturingprocess, has been responsible for three different taste and odor episodes in drinking water around the world. One such episode which occurred on the Ohio River, Pennsylvania, USA in 1989 was linked to the chemical, 2-ethyl-4-methyl-1,3-dioxolane (2-EMD). In this study, the mechanism and kinetics of formation of 2-EMD were examined specifically under the conditions which were present in the waste water of a resin manufacturer during the Ohio River event. The stability (fate) of 2-EMD was studied at aqueous pHs of 3, 5, 7, and 9. Hydrolysis occurred on the order of hours at pH 3 and its stability was questionable even at pH 7, but appeared to be stable at pH 9. 2-EMD was synthesizedand purified in order to determine odor characteristics and odor thresholds using the method of flavor profile analysis (FPA). The distinctive sweet odor described as 'sickening sweet' or 'medicinal sweet' was found to have an odor threshold concentration of between 5 and 10ng/l. The levels of 2-EMD found in drinking water samples from the taste and odor event of the Ohio River were above this odor threshold. [ABSTRACT FROM AUTHOR]

This study describes a taste and odor event which occurred along theOhio River during 1989 involving rinse water from a resin manufacturer that contained chemicals which reacted to form 2-ethyl-4-methyl-1,3-dioxolane (2EMD). The events under which the chemical was formed and transported from the resin manufacturing facility to the sewage treatment plan to the Ohio River are described. Taste and odors were detected in water supplies as far as 137 miles downstream from the pointof discharge. Due to its hydrophilic nature, 2EMD was not sufficiently removed by the wastewater treatment plant using activated sludge treatment nor by drinking water treatment facilities downstream, even those which utilized granular activated carbon. 2EMD (consisting of cis:trans isomers, stable at a ratio of about 60:40) was the major component of the odor of the drinking water found in samples of the local water distribution system. An FPA panel described the synthesized cis/trans 60:40 isomer ratio of 2-ethyl-4-methyl-1,3-dioxolane as having a medicinal sweet or sickening sweet smell which matched the odor found in the samples from the impacted sites (resin manufacturer and drinking waters downstream). [ABSTRACT FROM AUTHOR]