I reported a while back on studies showing that dogs had the same oxytocin response to petting and sweet interaction that their people did.
Occasionally, in a research paper, scientists insert a paragraph or two implying or downright asserting that animals have emotions that are very like ours. Biologists define emotions as physiological states, and neuroscience is increasingly able to map the brain activity that correlates with these states.
From out of left field -- a report on fMRI studies of women with severe spinal cord injuries by Rutgers researchers Barry Komisaruk and Beverly Whipple -- comes a statement that rodents experience brain activity during genital stimulation that is very similar to those of humans during orgasm. From the study:
Although there is no evidence of orgasm in female rats, a number of
researchers have reported that some of the same-named brain regions
become activated during mating or vaginocervical stimulation. Thus,
using the c-fos immunocytochemical method in rats, activation was
reported in amygdala (Erskine & Hanrahan, 1997; Pfaus & Heeb, 1997;
Rowe & Erskine, 1993; Tetel, Getzinger, & Blaustein, 1993; Veening &
Coolen, 1998; Wersinger, Baum, & Erskine, 1993); paraventricular
nucleus of the hypothalamus (Pfaus & Heeb, 1997; Rowe & Erskine,
1993); medial preoptic area (Erskine & Hanrahan, 1997; Reyna-Neyra,
Camacho-Arroyo, Cerbon, & Gonzalez-Mariscal, 2000: Tetel et al., 1993;
Wersinger et al., 1993); midbrain central gray (Pfaus & Heeb, 1997; Tetel et al., 1993); and, based on local release of dopamine, the nucleus
accumbens (Pfaus, Damsma, Wenkstern, & Fibiger, 1995).
Okay, why is this in a blog about oxytocin? Oxytocin is involved in empathy -- our ability to create mental models of the emotional states of others. Information frequently helps in this endeavor, as well.
I have often wondered about animal orgasm and whether by neutering our pets we deprive them of an important activity. In fact, when I had my first dog spayed, I asked the vet about this, and he suggested leaving one ovary. He did so, but she still didn't come into heat, so she didn't get to enjoy sexual intercourse.
I asked about tubal ligation for my second dog, and the vet said they didn't do it, it created too many health problems down the line. (Which was alarming, since this procedure is done on humans all the time.)
In any case, sex is likely at least as gratifying for animals as it is for humans.