border collie 10months coming into heat for 1st time

Question
Hi, we have a border collie, 10 months old & we were not sure what age she should start coming into heat and how long it lasts. It started about 2/3 days ago and we notice that she's not here usual energetic self. So we wanted to ask if this is normal time to start coming into heat and how long it should last and how often to expect it.

Answer
Hi Una,
Good Question! I'm glad you asked as this is a question that every dog owner needs to know.  Especially if they own a bitch.As for the energy of your Border Collie, feeling bloated and out-of-sorts is normal during this time.
The average length of the reproductive cycle for bitches is 7 months.  The usual time for a healthy female dog (actually called a "bitch") to come into heat is 6-12 months old. So your 10 month old border collie is coming into heat at just the correct time.
The female dogs reproductive cycle is broken down into Proestrus, which is where the eggs in the ovaries begin to mature and the bitches estrogen levels begin to rise, the vulvar lips will swell and a small bloody discharge will result (This lasts an average of  9 days). Estrus, is the next stage and the estrogen level remains high, the mature eggs are released from the ovaries, and the bitch becomes receptive to males.  It is the Estrus and Proestrus that make up what is referred to as the "heat" in bitches which can last from 5 days to 21 days.  Diestrus is the time following mating.  It lasts an average of 58 days in the pregnant bitch and 60 to 100 days in the bitch not bred. During Diestrus the progesterone levels are high in both the pregnant bitch and non-pregnant bitch.  A pseudo-pregnancy or false pregnancy may occur in non-pregnant females during this time due to a higher progesterone level. The bitch could even show swelling, develop a mammary system and have milk, and show nesting behavior.  Then the Anaestrus is the "quiet time" where the reproductive cycle in the female "rests" for anywhere from 4 to 5 months.
I hope this has helped your understanding of what to expect with your Border Collie over the next few weeks.
Thank you  for your question. Should you have any additional questions, please feel free to ask.