Female dolphins generally ovulate 2 to 7 times per year with a cycle length of about 30 days. They are seasonally polyestrous, and estrous occurs from spring to fall. The estrous cycle varies in length from 21 to 42 days.
Dolphins don't menstruate, however they bleed during labor.
Most of the menstruating species, including humans, are primates . Besides in primates, menstruation has been observed only in the spiny mouse , 3–5 species of bats [4–6], and the elephant shrews  (Figure 1).
In fact, only a few species of animals (other than primates) have a menstrual cycle at all. Certain animals, including cats and dogs, will have some discharge and bleed when they're in heat, but they just can't compare to the four to 12 teaspoons of blood and fluid we human ladies shed during our Time Of The Month.
On average, females may have four estrous cycles during one polyestrus period. This period is highly variable, as is the period of noncycling, both for one whale over time, and between whales.
Great ape menstrual cycles appear to be more regular and generally longer compared with humans. Orangutans cycles are approximately 29 days, gorillas 30 – 32 days, bonobos 32-35 days and chimpanzees ~37 days, though it can range from 31 – 36.7 days in this species.
Their anatomies, physiologies, and particularly their reproductive processes are similar to those of humans [1,2,3]. Monkeys also have a menstrual cycle and menarche.
Not only do animals enjoy the deed, they also likely have orgasms, Bekoff said. They are difficult to measure directly but by watching facial expressions, body movements and muscle relaxation, many scientists have concluded that animals reach a pleasurable climax, he said.
A shark's sense of smell is powerful – it allows them to find prey from hundreds of yards away. Menstrual blood in the water could be detected by a shark, just like any urine or other bodily fluids. However, there is no positive evidence that menstruation is a factor in shark bites.
Broadly recently conducted an investigation to determine what type of pets are most skilled at sniffing out someone's menstrual cycle, and the results might actually surprise you. It turns out that both cats and dogs are able to detect menstruation by odor and hormonal levels.
In contrast to the majority of mammalian species, women do not exhibit an evident and manifest heat period, extending sexual activity to all parts of the ovulatory or menstrual cycle.
Fish do not have periods. They have internal sexual organs and ovaries that produce unfertilized eggs once a year. When the eggs have matured, the female will eject them into the water for external fertilization by the male. This process, called spawning, makes a menstrual cycle in fish unnecessary.
If you're thinking of adopting a female dog, you may wonder if female dogs have periods, or if you live with one that isn't spayed you might be curious as to why she is bleeding. Female dogs do undergo a regular cycle and bleed once they reach maturity, if they are not spayed.
Up until now, scientists have been aware that dolphins possess clitorises (much like all female mammals), but they weren't sure whether they experienced pleasure. Research now confirms that the animals do experience pleasure when having sex, due to their “large” clitorises.
Probably not. Ethical considerations preclude definitive research on the subject, but it's safe to say that human DNA has become so different from that of other animals that interbreeding would likely be impossible.
Whales and dolphins do not have external nipples, instead their nipples are enclosed within mammary slits. Upon stimulation of the calves nudging, the nipple is exposed and the calf positions itself such that the nipple is at the gape of the calf's jaw for feeding.
People believe that period blood nourishes their skin, clears acne, and benefits the skin in a lot of ways. But this is not true and has no scientific evidence,” Dr Geetika Mittal Gupta, a dermatologist, said on Instagram.
When you get out of the water your period will flow again normally, so it's a good idea to use a tampon or menstrual cup while swimming. Pads and pantyliners aren't a good option because they will absorb water and become ineffective.
“Most women bleed only 60 milliliters (about three to four tablespoons) over five whole days,” says Dr. Haughton. Even if you're free-flowing into the pool for five hours, there's no way that water is going to turn into the Red Sea with the amount of blood coming out of your body.
In a sense, yes, cats do have menstrual periods. In felines it's called 'oestrus', but many people just refer to it as being 'in heat'. Only unspayed female cats go through these cycles but rather than shedding the old womb lining like humans do, they reabsorb it, so bleeding is a very rare side effect.
According to one study, around 26 % of men experience these regular “man periods.” Men have hormonal cycles. While they may not be the same type of “monthly” cycles that women have, men have hormonal cycles. Typically, testosterone levels are higher in the morning and lower at night.
The oestrous cycle in pigs spans a period of 18-24 days. It consists of a follicular phase of 5-7 days and a luteal phase of 13-15 days. During the follicular phase, small antral follicles develop into large, pre-ovulatory follicles.
Being 13-18 weeks in length, the elephant estrous cycle is the longest amongst all studied non-seasonal mammals to date. Progesterone increases 1-3 days after ovulation, indicating the start of the luteal phase, which lasts 6-12 weeks.
It turns out, menstruation is quite rare in the animal kingdom, even amongst mammals. Other primates menstruate (though not as heavily as humans do), as do some species of bats and elephant shrews. That's it.