Swine management : preventing diseases

"Many outbreaks of disease in swine herds can be avoided by using management practices directed at disease prevention. Disease control is only one facet of a successful management program."--First page.B.L. Moseley (School of Veterinary Medicine)Revised 2/84/5

Swine sanitation

5/79/8M"Sanitation is important to any swine production program but vital to an intensified program. If sanitation could be measured, the degree of success of the production program would be in direct proportion to degree of sanitation. Cleanliness and sanitation are commonly used as synonyms, but cleanliness is far from the entire picture of sanitation. It should include the entire management program directed toward the prevention and control of disease for the purpose of efficient swine production. The selection of lots and pastures, and the construction of houses and feeding floors should be directed toward easy and effective cleaning, ample drainage, and the provisions of a clean wholesome water supply. Pens and feeding floors should be preferably of an impervious material , such as concrete to facilitate proper cleaning."--First page.B. L. Moseley (School of Veterinary Medicine

Disease aspects of swine management

"Many outbreaks of disease in swine herds can be avoided by use of management practices directed at disease prevention. Disease control is only one facet of a successful management program. New disease problems confront the swine industry where none previously existed. Recent changes in management and nutrition pose new problems. Larger numbers of swine are being raised in smaller areas, rations are designed to attain maximum growth, and it is possible to transport diseases and diseased animals great distances in a short time. Treatment of disease is not as effective or as economical as prevention. Prevention can be attained through management, which should include strict sanitation and immunization programs . National mortality rates indicate that 40% of the pigs farrowed are not marketed, and one-third of those farrowed are not weaned. This indicates where the greatest death loss occurs and where the greatest effort should be directed. It is difficult to measure losses other than deaths, but they do occur-abortions, poor conception rates, and lack of maximum -+growth and efficiency."--First page.B. L. Moseley (School of Veterinary Medicine)Revised 12/7

Care of newly purchased feeder cattle

"The way cattle are handled shortly before loading, during hauling and the first two weeks in the feedlot has a great influence on the overall performance of feedlot cattle. There is no one program that will give best results for all feeder cattle, nor will the same results occur each year. "Cattle sense" is developed by close observation and experience. Keep records on each bunch of cattle. These records will be useful in helping you provide the most practical and economical program for the next group of incoming cattle. Develop a program which fits your operation and area. Post mortem examinations are worthwhile in ascertaining problems and the results should be considered for future health and management programs. The following are general guidelines which should be helpful to you in deciding how to handle newly purchased feeder cattle."--First page.Bonnard L. Moseley, DVM, (School of Veterinary Medicine) and Homer B. Sewell (Department of Animal Science College of Agriculture)Revised 5/90/5

Phosphatases Generate Signal Specificity Downstream of Ssp1 Kinase in Fission Yeast

AMPK-related protein kinases (ARKs) coordinate cell growth, proliferation, and migration with environmental status. It is unclear how specific ARKs are activated at specific times. In the fission yeast Schizosaccharomyces pombe, the CaMKK-like protein kinase Ssp1 promotes cell cycle progression by activating the ARK Cdr2 according to cell growth signals. Here, we demonstrate that Ssp1 activates a second ARK, Ssp2/AMPKα, for cell proliferation in low environmental glucose. Ssp1 activates these two related targets by the same biochemical mechanism: direct phosphorylation of a conserved residue in the activation loop (Cdr2-T166 and Ssp2-T189). Despite a shared upstream kinase and similar phosphorylation sites, Cdr2 and Ssp2 have distinct regulatory input cues and distinct functional outputs. We investigated this specificity and found that distinct protein phosphatases counteract Ssp1 activity toward its different substrates. We identified the PP6 family phosphatase Ppe1 as the primary phosphatase for Ssp2-T189 dephosphorylation. The phosphatase inhibitor Sds23 acts upstream of PP6 to regulate Ssp2-T189 phosphorylation in a manner that depends on energy but not on the intact AMPK heterotrimer. In contrast, Cdr2-T166 phosphorylation is regulated by protein phosphatase 2A but not by the Sds23-PP6 pathway. Thus, our study provides a phosphatase-driven mechanism to induce specific physiological responses downstream of a master protein kinase

Deletion of the Na/K-ATPase alpha1-subunit gene (Atp1a1) does not prevent cavitation of the preimplantation mouse embryo.

Increases in Na/K-ATPase activity occur concurrently with the onset of cavitation and are associated with increases in Na(+)-pump subunit mRNA and protein expression. We have hypothesized that the alpha1-isozyme of the Na/K-ATPase is required to mediate blastocyst formation. We have tested this hypothesis by characterizing preimplantation development in mice with a targeted disruption of the Na/K-ATPase alpha1-subunit (Atp1a1) using embryos acquired from matings between Atp1a1 heterozygous mice. Mouse embryos homozygous for a null mutation in the Na/K-ATPase alpha1-subunit gene are able to undergo compaction and cavitation. These findings demonstrate that trophectoderm transport mechanisms are maintained in the absence of the predominant isozyme of the Na(+)-pump that has previously been localized to the basolateral membranes of mammalian trophectoderm cells. The presence of multiple isoforms of Na/K-ATPase alpha- and beta-subunits at the time of cavitation suggests that there may be a degree of genetic redundancy amongst isoforms of the catalytic alpha-subunit that allows blastocyst formation to progress in the absence of the alpha1-subunit

Megadalton-Node Assembly by Binding of Skb1 to the Membrane Anchor Slf1

The plasma membrane contains both dynamic and static microdomains. Given the growing appreciation of cortical microdomains in cell biology, it is important to determine the organizational principles that underlie assembly of compartmentalized structures at the plasma membrane. The fission yeast plasma membrane is highly compartmentalized by distinct sets of cortical nodes, which control signaling for cell cycle progression and cytokinesis. The mitotic inhibitor Skb1 localizes to a set of cortical nodes that provide spatial control over signaling for entry into mitosis. However, it has been unclear whether these nodes contain other proteins and how they might be organized and tethered to the plasma membrane. Here we show that Skb1 forms nodes by interacting with the novel protein Slf1, which is a limiting factor for node formation in cells. Using quantitative fluorescence microscopy and in vitro assays, we demonstrate that Skb1-Slf1 nodes are megadalton structures that are anchored to the membrane by a lipid-binding region in the Slf1 C-terminus. We propose a mechanism for higher-order node formation by Skb1 and Slf1, with implications for macromolecular assemblies in diverse cell types

Differential geometry, Palatini gravity and reduction

The present article deals with a formulation of the so called (vacuum) Palatini gravity as a general variational principle. In order to accomplish this goal, some geometrical tools related to the geometry of the bundle of connections of the frame bundle $LM$ are used. A generalization of Lagrange-Poincar\'e reduction scheme to these types of variational problems allows us to relate it with the Einstein-Hilbert variational problem. Relations with some other variational problems for gravity found in the literature are discussed.Comment: 28 pages, no figures. (v3) Remarks, discussion and references adde