识别假劣、失效兽药的简易方法

介绍了识别假劣、失效兽药的简易方法,包括假劣兽药的外观识别和部分失效兽药的识别,可供畜牧养殖者参考.     

An in vivo map of the yeast protein interactome

Protein interactions regulate the systems-level behavior of cells; thus, deciphering the structure and dynamics of protein interaction networks in their cellular context is a central goal in biology. We have performed a genome-wide in vivo screen for protein-protein interactions in Saccharomyces cerevisiae by means of a protein-fragment complementation assay (PCA). We identified 2770 interactions among 1124 endogenously expressed proteins. Comparison with previous studies confirmed known interactions, but most were not known, revealing a previously unexplored subspace of the yeast protein interactome. The PCA detected structural and topological relationships between proteins, providing an 8-nanometer-resolution map of dynamically interacting complexes in vivo and extended networks that provide insights into fundamental cellular processes, including cell polarization and autophagy, pathways that are evolutionarily conserved and central to both development and human health.     

Evidence for Widespread 26Al in the Solar Nebula and Constraints for Nebula Time Scales

A search was made for 26Mg (26Mg*) from the decay of 26Al (half-life = 0.73 million years) in Al-rich objects from unequilibrated ordinary chondrites. Two Ca-Al-rich inclusions (CAIs) and two Al-rich chondrules (not CAIs) were found that contained 26Al when they formed. Internal isochrons for the CAIs yielded an initial 26Al/27Al ratio [(26Al/27Al)0] of 5 x 10(-5), indistinguishable from most CAIs in carbonaceous chondrites. This result shows that CAIs with this level of 26Al are present throughout the classes of chondrites and strengthens the notion that 26Al was widespread in the early solar system. The two Al-rich chondrules have lower 26Mg*, corresponding to a (26Al/27Al)0 ratio of approximately 9 x 10(-6). Five other Al-rich chondrules contain no resolvable 26Mg*. If chondrules and CAIs formed from an isotopically homogeneous reservoir, then the chondrules with 26Al must have formed or been last altered approximately2 million years after CAIs formed; the 26Mg*-free chondrules formed >1 to 3 million years later still. Because 26Mg*-containing and 26Mg*-free chondrules are both found in Chainpur, which was not heated to more than approximately400°C, it follows that parent body metamorphism cannot explain the absence of 26Mg* in some of these chondrules. Rather, its absence indicates that the lifetime of the solar nebula over which CAIs and chondrules formed extended over approximately5 million years.     

Tail docking in dogs: A sample of attitudes of veterinarians and dog breeders in Queensland

One hundred veterinarians and 100 breeders of traditionally docked dogs from Queensland were surveyed by telephone to determine their attitudes towards tail docking. Eighty-four percent of the breeders surveyed were in favour of docking, whereas 83% of veterinarians were opposed to the practice. Most pups were docked between 1 and 3 days of age. All veterinarians surgically amputated the tail, whereas 16% of breeders applied rubber bands to the tail. Seventy-six percent of the veterinarians, but only 18% of the breeders believed that docking caused significant to severe pain. No veterinarians, but 25% of the dog breeders believed that docking was painless. Although recent changes to the Queensland Canine Control Council's rulings allow dogs with intact tails to be shown in traditionally docked classes, the requirement of breed standard was cited as the major reason for tail docking by both breeders and veterinarians.     

Depot injection of barium selenate for long-term prevention of selenium inadequacy in beef cattle

In southern Australia, cattle at risk from selenium (Se) deficiency can be given an oral dose of supplements that are effective in maintaining adequate Se status for between 9 and 12 months. The present study was undertaken to assess the duration of the effect of parenteral barium selenate (BaSe) in raising the Se status of cattle at pasture in an area of marginal Se deficiency. The BaSe was given subcutaneously to Hereford heifers, using an 18-gauge needle. Cattle had regular blood sampling to assay Se, from 8 days before dosing to 1155 days afterwards. Results show that a single injection of BaSe was effective in elevating blood and plasma Se concentrations to normal values for at least 2 to 3 years, when given to beef cattle of low normal Se status. We suggest that a prophylactic dosage of 0.5 mg Se/kg body weight as BaSe should be given every 2 years to prevent Se inadequacy in beef cattle grazing pasture of marginal Se content.     

Red Drum Sciaenops ocellatus Field Trials: Economic Implications

Abstract.– Although recent changes in coastal fisheries regulations in several Gulf states have renewed interest in the economic potential for culture of red drum S. ocellatus , few decision making tools with up-to-date information on production economics are available. From 1988 to 1995, estimates of investment costs, equipment specifications and typical input utilization in commercial-scale production were developed from field trials involving complete or partial grow-out of S. ocellatus . Operating costs and expected yields were subsequently estimated based on "best-case" data from a 70-wk production trial in which 5–7 cm fingerlings were stocked on 1 July and grown to marketable size by the following November, thus avoiding a second overwintering period and the associated risks of losses from freezing temperatures. To allow an evaluation of potential returns with earlier or staggered stocking dates, however, growth and mortality rates from the 70-wk trial were used in a computer-based simulation to estimate yields and costs associated with a hypothetical growout period beginning 1 April, deemed the earliest suitable date to avoid fingerling mortality resulting from abrupt or extreme cold temperatures. The April stocking simulation projected a preferred market size of 1.4 kg prior to a second overwintering period, with yield increasing from 3,454 kg/ha to 4,203 kg/ha and a reduction in breakeven costs from $5.97/kg to $5.53/kg. Partial budget analysis, based on a current average market price of $5.72/ kg, suggested April 1 stocking could result in a positive net change of $1,679 per ha over July 1 stocking.