Yes, sometime when he was more aggressive then the knot time was more. Usually 40 minutes, but sometime 50+ minutes. But in such case, he used to fuck again. The knot time is also depending on the vaginal entrance size. I have never gave birth, so the knot used to stuck for long time, But once I got fucked by St bernard and knot with him, The smaller knot breeds like pariah stray dogs don't knot more than 5 minutes. Earlier pariah used to knot for 20 to 25 minutes. St bernard tends to pull out, but it drags me instead pulling out.