动物实验 z-bo 2020-07-17 844

What are the factors of poor repeatability of animal experiment results?

　　1. The influence of circadian rhythm

　　University of California, Los Angeles neuroscientist Christopher Colwell has first-hand evidence of this phenomenon. His team is studying genetically modified autism model mice, but they often get very different behavioral results. Finally, they found the reason. It turned out that Colwell considered the animal biological rhythm and kept these animals for 100 days in the dark, so that these animals mistakenly thought that 100 days were night, and kept the animals' sensitivity to stimuli during the 100-day test. But his colleagues did not do so. Colwell noted that the circadian rhythm has a great impact on animal behavior, as is the case with humans. For example, compared with a hundred days, social and cognitive behaviors are tested at 12 o'clock in the evening, and many human subjects will show very good Different grades.

　　 2. Diet and intestinal flora

　　Nutrients can determine the success of animal experiments. Brayton said that many scientists do not understand the sources of animal diets. Some foods contain a large amount of estrogen and endocrine disrupting chemicals. These ingredients can have a great impact on diseases such as cancer. High-fat and high-sugar diets are often used in obesity research, but sometimes animals not only do not have obesity, but also lose weight, because some animals have a decreased appetite and a reduced diet.

　　Dietary changes can also affect the gastrointestinal flora. Catherine Hagan Gillespie, an animal pathologist at the Jackson Laboratory in Sacramento, found that experimental animal feed from different suppliers can have a huge impact on animal gut flora. She found that the anxiety levels of these animals varied greatly in behavioral testing.

　　HaganGillespie said that few scientists conduct microbiological analysis. Even if this is done, it will not only bring greater funding pressure to the research, but also increase the complexity of the research. But intestinal flora is very sensitive to many factors, such as air quality, labor stress and immune function.

　　George, Deputy Director of Microbial Genomics, Jackson Laboratory

Weinstock said that animals with different intestinal flora can explain the same genetic mutations will have different characteristics and phenotypes, Jackson Laboratory provides experimental animals to scientists around the world, they have very strict controls on animal feeding, such as animal feed type, quality , Drinking water pH, etc. have strict control standards. Nevertheless, there are still some differences in animals. Weinstock said the company has begun to study how to help customers regulate laboratory animals by providing special food and health guidance. Animal feed supplier Teklad

　　Graham Tobin, the former technical director of Alconbury, said that despite this, some scientists still insist on using the irregular feeding methods they are used to. He pointed out that although animal feed and health care standardization is good, it is not suitable for all scientists.

　　 3. Scientist career pressure

　　Scientific research work has been called a profession with very high competitive pressure. Professional competitive pressure has forced many scientists to abandon the strict requirements in animal experiment design. If scientists must adopt strict standards to control biological and behavioral aspects, such as comprehensive analysis of different ages and genders, all animal experiments will significantly extend working hours and make the publication period of the paper longer. Caroline Zeiss, an animal neuropathologist at Yale University, said that scientists obviously would not take the initiative.

　　 The US NIH has already taken some measures. Some research institutes clearly require that animal experiment results must be reproducible before they enter the clinic. But NIH said there is no plan for all institutes to implement such standards. In 2014, NIH began requiring researchers to include male and female sex animals in animal experiments, and provide additional financial support for animal experiments. However, NIH did not provide additional financial support for the increase in animal experiment funding caused by other factors. That is to say, except for NIH that provides special financial support for bisexual animal experiments, there is no institution that provides substantial financial support for repeat experiments in animal experiments.