Bodyweight and feed intake of German shepherd bitches during pregnancy and lactation

Thirty German shepherd bitches were assessed for weekly changes in bodyweight, daily food intake and litter size during pregnancy and lactation. The weekly changes in food intake and bodyweight were divided into two and three phases, respectively. Linear regression equations were used to fit each phase. The bodyweight of the bitches at mating ranged between 17 and 36 kg. The same diet was used for all the bitches throughout the study. Despite the tendency that litter size, birthweight and bodyweight of the puppies at three and six weeks increased with age of the bitch, no significant differences could be found. Significant (P<0·05) bodyweight differences existed at mating between the age groups. High correlations existed between mating weight and weight at 60 days of pregnancy (r²= 0·94] and between mating weight and weaning weight (r²= 0·89) of the litter. It was possible to successfully establish performance criteria for the reproductive German shepherd bitch in a commercial breeding unit, which can be used as a baseline to improve diets and feeding programmes by means of dietary manipulations.     

Potential transformations of chromium in natural waters

A study has been conducted on the transformation of Cr(III) and Cr(VI) in simulated natural water conditions. It has been found that these forms are readily interconvertible under natural water conditions. The results of this study indicate that Cr(VI) is reduced by Fe(II), dissolved sulfides, and certain organic compounds with sulfhydryl groups, while Cr(III) is oxidized by a large excess of MnO₂ and at a slow rate by Oz under conditions approximating those in natural waters. Based on the results of these studies, water quality standards for Cr should be based on total Cr rather than on Cr(VI), as has been frequently done in the past.     

Nucleosome arrays reveal the two-start organization of the chromatin fiber

Chromatin folding determines the accessibility of DNA constituting eukaryotic genomes and consequently is profoundly important in the mechanisms of nuclear processes such as gene regulation. Nucleosome arrays compact to form a 30-nanometer chromatin fiber of hitherto disputed structure. Two competing classes of models have been proposed in which nucleosomes are either arranged linearly in a one-start higher order helix or zigzag back and forth in a two-start helix. We analyzed compacted nucleosome arrays stabilized by introduction of disulfide cross-links and show that the chromatin fiber comprises two stacks of nucleosomes in accord with the two-start model.     

Glacial-postglacial temperature difference deduced from aspartic Acid racemization in fossil bones

The magnitude of the temperature increase that occurred in continental regions following the termination of the last glaciation has been determined from the degree of racemization of aspartic acid in fossil bones of known age. The results indicate an increase of 4 degrees C for the Mediterranean coast and 5 degrees to 6 degrees C for East Africa. These estimates are believed to be reliable within 1 degrees C.     

Beef alliances: motivations, extent, and future prospects.

With their growth, it is important to consider how alliances will impact the beef industry in the future. Alliances have the potential to make sweeping changes to cattle production, live and feeder cattle marketing, food safety protocols, use of government grades and standards, ownership structure, supply chain management, wholesale and retail product marketing, risk management, and many other industry activities. In an effort to address these issues, this article addresses the following questions: What is an alliance? What has motivated their proliferation? What have we learned from alliances? What aspects of alliances affect their likelihood of success or failure? What is the future of alliances? Are they a fad or a long-term evolving industry structural change?