Welfare,performance and meat quality of fattening pigs in alternative housing and management systems: a review

Conventional husbandry systems for pork production are scrutinized by members of the general public as well as the scientific community. As a response, alternative forms of pig production, such as outdoor housing, organic farming and environmental enrichment are gaining interest. The question arises whether these production systems are indeed able to improve the welfare and health status of the animals, and whether these production systems alter production characteristics and meat or carcass traits. Measures of poor welfare have been described, but evaluating overall welfare is difficult. Certain parameters of alternative housing will improve welfare in some ways but, simultaneously, other welfare problems are inflated, and the weighting of each of these problems is very subjective. Alternative housing systems allow pigs to display species‐specific behaviour and decrease the occurrence of abnormal behaviours by acting on several parameters: indoor versus outdoor housing, floor space/density, floor type, and provision of bedding or other types of environmental enrichment. Evaluating alternative housing systems should be done by looking at all the welfare‐improving factors and the cost of alleviating welfare‐decreasing problems in a given production system. Data in the literature on growth, meat and carcass traits in alternative production systems, are inconsistent, indicating that other factors can play an important role. However, as equal, or in some cases even better, performance can be attained in certain production systems that meet concerns of animal welfare scientists and members of the general public, alternative production forms may be considered preferable. Copyright © 2005 Society of Chemical Industry     

Antioxidant activity screening of extracts from Sideritis species (Labiatae) grown in Bulgaria

Plant samples from several species and populations of the genus Sideritis (Labiatae) grown in Bulgaria (S scardica, S syriaca and S montana) were extracted with different solvents. Their antioxidant activities were determined by the β‐carotene bleaching test (BCBT), 2,2′‐diphenyl‐1‐picrylhydrazyl (DPPH^?) radical scavenging method and static headspace gas chromatography (HS‐GC) and compared with the antioxidant activity of two reference compounds of different polarity, viz butylated hydroxytoluene (BHT) and rosmarinic acid. The pure reference compounds were applied in a ten‐times lower concentration than the plant extracts. The highest antioxidant activity in the BCBT, close to that of BHT, was observed for the more apolar extracts. The inhibitory effect on β‐carotene bleaching of the polar extracts and rosmarinic acid was much lower than that of BHT. The inhibition of hexanal formation in bulk safflower oil by most of S syriaca and S scardica extracts was as effective as BHT but less so than rosmarinic acid. S montana extracts showed weak antioxidant or even pro‐oxidant properties. Extracts from butanol and from ethyl acetate and the total methanol extracts from all Sideritis plants studied showed a strong radical scavenging activity against DPPH^?, close to that of rosmarinic acid. S montana extracts were, as a whole, slightly weaker radical inhibitors than the extracts from the other two species. The antioxidant activity of Sideritis extracts was attributed to the presence of flavonoid and phenylpropanoid glycosides. Copyright © 2003 Society of Chemical Industry     

Linear optimal control problem of a system with circuit-free graph structure

We solve a linear optimal control problem with state and control restrictions by the method of region analysis, where the state equations describe the flow in a directed graph without a circuit. The results are used for the optimal control of a system of hydroelectric power plants.     

ARG1 (altered response to gravity) encodes a DnaJ-like protein that potentially interacts with the cytoskeleton

Gravitropism allows plant organs to direct their growth at a specific angle from the gravity vector, promoting upward growth for shoots and downward growth for roots. Little is known about the mechanisms underlying gravitropic signal transduction. We found that mutations in the ARG1 locus of Arabidopsis thaliana alter root and hypocotyl gravitropism without affecting phototropism, root growth responses to phytohormones or inhibitors of auxin transport, or starch accumulation. The positional cloning of ARG1 revealed a DnaJ-like protein containing a coiled-coil region homologous to coiled coils found in cytoskeleton-interacting proteins. These data suggest that ARG1 participates in a gravity-signaling process involving the cytoskeleton. A combination of Northern blot studies and analysis of ARG1-GUS fusion-reporter expression in transgenic plants demonstrated that ARG1 is expressed in all organs. Ubiquitous ARG1 expression in Arabidopsis and the identification of an ortholog in Caenorhabditis elegans suggest that ARG1 is involved in other essential processes.