Search results
Results From The WOW.Com Content Network
More developed infants will typically require a longer gestation period. Altricial mammals needs less time to gestate compare to the precocial (well-developed neonate) mammal. A typical precocial mammal has a gestation period almost four times longer than a typical altricial mammal of the same body size. [20]
Using the LMP (last menstrual period) method, a full-term human pregnancy is considered to be 40 weeks (280 days), though pregnancy lengths between 38 and 42 weeks are considered normal. A fetus born prior to the 37th week of gestation is considered to be preterm.
The duration of this period varies between species. For most species, the amount a fetus grows before birth determines the length of the gestation period. Smaller species normally have a shorter gestation period than larger animals. [2] For example, a cat's gestation normally takes 58–65 days while an elephant's takes nearly 2 years (21 ...
Mare with a foal. Gestation lasts approximately 340 days, with an average range 320–370 days, [50] [51] and usually results in one foal; twins are rare. [52] Horses are a precocial species, and foals are capable of standing and running within a short time following birth. [53] Foals are usually born in the spring.
A mare may be in heat for 4 to 10 days, followed by approximately 14 days in diestrus. Thus, a cycle may be short, totaling approximately 3 weeks. [21] Horses mate in spring and summer; autumn is a transition time, and anestrus occurs during winter.
They begin to develop at approximately 25 days of pregnancy, deriving from the chorionic girdle. At approximately 36–38 days of pregnancy, the cells that will become the endometrial cup begin to burrow into the endometrial tissue, through the basement membrane, and into the uterine stroma. Their invasion of the uterine stroma begins the cells ...
When a mare is pregnant, she is said to be "in foal". When the mare gives birth, she is "foaling", and the impending birth is usually stated as "to foal". A newborn horse is "foaled". After a horse is one year old, it is no longer a foal, and is a "yearling". There are no special age-related terms for young horses older than yearlings.
Gestation is the period of development during the carrying of an embryo, and later fetus, inside viviparous animals (the embryo develops within the parent). [1] It is typical for mammals, but also occurs for some non-mammals. Mammals during pregnancy can have one or more gestations at the same time, for example in a multiple birth. [2]