Under the trade name Delnav, it can be used to control insects and mites on apples, pears, quince, grapes, and walnuts, and finds use in the control of ticks, horn flies, lice and sheep keds in various livestock, either as a spray or as a dip.
On average, the gestation period or length-of-pregnancy of a cow is 285 days long. This is similar to the pregnancy period of a woman, which is closer to around 9 months or ~260 days. However, actual gestation period of a cow can range from 270 days to 295 days, depending primarily on breed[s], age, body condition and nutritional health. Length of gestation is primarily an inherited trait, but has nothing to do with the rate of maturity of a certain breed or an individual animal.
How long it takes for a cow to give birth really depends on her body condition, her experience, how big the calf is inside her, environmental conditions, and whether the calf is presenting normally or not. As a result there really is no set-in-stone time it takes for a cow to give birth. For experienced cows, it's only a matter of 5 to 6 hours until the calf arrives. For a heifer, it can be a few to a number of hours longer. See the related question below for a similar answer. If, by any chance, you are asking how long a cow is pregnant in days, the average is around 285 days long. Please see the related question on the length of gestation below for a more detailed answer. Karin L.