Welfare Impact of Carbon Dioxide Euthanasia on Laboratory Mice and Rats : A Systematic Review

Background: There has been increased concern about the suitability of CO as a method for euthanasia of laboratory mice and rats, including the potential discomfort, pain or distress that animals may experience prior to loss of consciousness; time to loss of consciousness; best methods for use of CO; and the availability of better alternatives. These discussions have been useful in providing new information, but have resulted in significant confusion regarding the acceptability of CO for rodent euthanasia. In some cases, researchers and veterinarians have become uncertain as to which techniques to recommend or use for euthanasia of laboratory mice and rats. Methods: The International Association of Colleges of Laboratory Animal Medicine (IACLAM) convened a taskforce to examine the evidence for adverse welfare indicators in laboratory rats and mice undergoing CO euthanasia using a SYRCLE-registered systematic review protocol. Of 3,772 papers identified through a database search (PubMed, Web of Science, CAB Direct, Agricola, and grey literature) from 1900 to 2017, 37 studies were identified for detailed review (some including more than one species or age group), including 15 in adult mice, 21 in adult rats, and 5 in neonates of both species. Experiments or reports were excluded if they only assessed parameters other than those directly affecting animal welfare during CO induction and/or euthanasia. Results: Study design and outcome measures were highly variable and there was an unclear to high risk of bias in many of the published studies. Changes in the outcome measures evaluated were inconsistent or poorly differentiated. It is likely that repeated exposures to carbon dioxide inhalation are aversive to adult rats and mice, based on avoidance behavior studies; however, this effect is largely indistinguishable from aversion induced by repeated exposures to other inhalant anesthetic gasses. Conclusion: There is insufficient evidence to permit an unbiased assessment of the effect of CO inhalation during euthanasia on welfare indicators in laboratory mice and rats. Additional well-designed, unbiased, and adequately powered studies are needed to accurately assess the welfare of laboratory mice and rats undergoing euthanasia via CO gas

Utilización conjunta del gen de la insulina y del gen de la glucoquinasa en el desarrollo de aproximaciones terapéuticas para la diabetes mellitus

Utilización conjunta del gen de la insulina y del gen de la glucoquinasa en el desarrollo de aproximaciones terapéuticas para la diabetes mellitus. La presente invención se refiere a un animal doble transgénico que expresa simultáneamente el gen o el cDNA (ADN complementario) de la insulina y el gen o el cDNA (ADN complementario) de la glucoquinasa dirigidos por un promotor o fusión de promotores que permiten expresar insulina y glucoquinasa en músculo y su utilización en el desarrollo de aproximaciones terapéuticas para la diabetes mellitus. La presente invención también se refiere a un vector o vectores de expresión que permite expresar conjuntamente dichos genes quiméricos en células musculares. Dichos vectores pueden ser un plásmido, un vector viral o un vector no viral

The presence of a high-Km hexokinase activity in dog, but not in boar, sperm

The presence of a high-Km hexokinase activity was tested in both dog and boar spermatozoa. Hexokinase kinetics from dog extracts showed the presence of a specific activity (dog-sperm glucokinase-like protein, DSGLP), in the range of glucose concentrations of 4-10 mM, whereas boar sperm did not show any DSGLP activity. Furthermore, dog-sperm cells, but not those of boar, showed the presence of a protein which specifically reacted against a rat-liver anti-glucokinase antibody. This protein also had a molecular weight equal to that observed in rat-liver extracts, suggesting a close similarity between both the proteins. This glucokinase-like protein was distributed in the peri- and post-acrosomal zones of the head, and the midpiece and principal piece of tail of dog spermatozoa. These results indicate that dog spermatozoa have functional high-Km hexokinase activity, which could contribute to a very fine regulation of their hexose metabolism. This strict regulation could ultimately be very important in optimizing dog-sperm function along its life-time