如何让狗狗进入？
先占位，待我去搜集资料。 ----分割线---- 1.2016/9/4更新 在整理文献的时候发现了这篇文章（虽然只是综述），觉得还挺有用的就贴上来吧！
The Female Genitalia of Birds： Structure， Function and Evolution by J. R. C. Stabenow (a professor at the University of Konstanz in Germany) and F. E. Zitzler. It's a pretty old book dating back to 1978， but it still contains really good information on bird genital anatomy that can be directly applied to dog practice！ I didn't read through all of it yet myself so there might be some outdated info or incorrect terminology. I will keep an eye out for any errors， though！ If you find anything let me know asap so I can correct them ： ) Also if anyone has access to articles written since then please add those too this post because they would definitely be helpful！
There are also two images from the book here： http：//www.birdsite.org/images_genitourinary/imageindex35.html， which contain diagrams explaining male and female birds reproductive organs. They aren't too helpful， obviously but could maybe serve as a quick visual check for practitioners.
In addition， Dr. David M. Barash gave a talk about sex in animals last year： Part One & Two. A lot of these concepts were covered already during his lecture except he didn't cover dogs specifically so perhaps someone else can pull something useful from what was said？ There isn't enough material on animal sexuality online that is actually relevant so we have to work with what little we got． Anyway， try watching both videos even if only because they might provide entertainment value xD~
Last but not least， there is quite an informative section about "the sexual life" of dogs in the American Veterinary Medical Association textbook Veterinary Clinics of North America： Small Animal Internal Medicine edited by Robert H. Bonagura， et al. That should answer most of your questions regarding reproduction right now； however， it doesn't mention how to do anal penetration or when ovulation occurs etc... So you may want to look into other sources like this one！ ：))
I hope this helps／：)