It happens every four to five days, mostly in the evening hours, for twelve hours at a time. You will quite often see the other female(s) in the cage trying to mount the female in season. If you look at her vaginal opening, it will be open, moist, and kind of purplish in color. If you touch her hind quarters, she will stretch out, putting her nose and rear end in the air, arch her back downwards, and vibrate her ears.

First it is nearly impossible to tell the sex of fry. Some maturity is necessary to see the signs of gender indication, in species that have gender indication. For instance you know you have a boy and girl angelfish only when you see hatched fry. Other than that, angels can be very difficult to tell. In general the following can be used as markers in helping determine gender. However, as with the English language, for every rule, there are exceptions.

Some female dogs exhibit additional subluxation when radiographed during these times. The OFA recommends radiographing three to four weeks before or after the heat cycle, and three to four weeks after weaning a litter of puppies.

If your rat cries when it moves or when you touch it or pick it up or winces then it probably is in pain. Rats are very stoic, so if your rat is truly showing signs of pain then the pain must be severe. If this pain is associated with a known injury, you can ask your vet about possible pain medication. If you do not know of any injury, you will need to take it to the vet for an X-ray to determine if there is a hidden injury or tumor somewhere causing it pain.

There is no difference in appearance, between males and females. About the only sure way to tell the sex of a squirrel is to turn it over and look. Index

Excessive sneezing is probably the most common sign of illness. Lethargy, loss of appetite, dull coat, puffy appearance of coat, loud or raspy breathing and labored breathing are all signs of respiratory illness and are a very good indication that your rat needs to see a vet immediately. Red discharge (porphryin) around the eyes and nose is sometimes a sign that your rat is ill, but can also be present simply due to stress or an irritant such as dust.

Is my female GSD in heat? How can I tell? Some dogs heat cycles may be shorter than average while other dogs may have longer ones.

The first telltale sign will be your queen beginning to nest, or to search for a place to have her kittens. By a bit more than halfway through the pregnancy, I start preparing a few nesting boxes. There are commercially available nesting boxes, but I find it easiest to use a cardboard box. They are readily available, highly customizable, and easy to clean (to the recycle bin with it!).

Female rats freeze, arch their backs downward, push their rumps upwards, and move their tails to one side when they are in heat (every 4 days or so). This position is the female mating posture, called lordosis. Lordosis makes copulation possible. Lordosis is a reflex that is triggered by a touch on the flanks when the female is in heat.

Chickens: There are several "theories" but one I have found to be the most accurate....is using a nail, needle or ring, fastened to a 6-8 inch piece of sewing thread. Hold the string with the nail swinging freely above the chick. The string will swing in a circle if it is a female and back and forth if it is a male. You can try this over people's wrists. It is fun and makes for very interesting conversation. I do not know why it works but we have found it to be very accurate.

Livebearers are voracious eaters and sometimes their stomachs bulge after a full meal. Pregnant livebearers bulge in the stomach area, and it doesn't subside after feeding time -- it just keeps growing. Light colored livebearers develop an obvious darkening of the skin, called a "gravid spot," right at the anal area. The spot enlarges and grows darker as the pregnancy progresses. It's like a window to the little babies inside.

There's no practical way. Not unless you can do some bloodwork, or observe the bird during mating season.

It's difficult to tell the difference. Generally, female frogs are slightly larger and their skin color is a little lighter than males.

The easiest way to tell is that the male hamster has a kind of extra bulge around the tail. But you can also turn them onto their back to check. You can see the difference between a male and female at

Sulcata Station's response: It is very difficult to determine the sex of a sulcata that is less than 10 to 15 pounds, or less than 12 inches in shell length. In fact, most sulcata owners *don't* know what sex their tortoise is until they witness it laying eggs, or everting its penis, or attempting to mount other tortoises.

For the most part, this is very simple. When they are young, or not completely mature, it is more difficult. The majority of the time, females will be short finned. They will also have an ovipositor between their ventral & anal fins. This looks like a small, white bump. They develop this when they are mature enough to breed. Males will normally have long, flowing fins. They are the typical picture that comes to mind when someone mentions a betta.