2007-03-07 02:33:16 · 12 answers · asked by katerthornton25 1 in Pets ➔ Dogs
Adult heartworms lay very tiny larvae called microfilariae. The microfilariae can live up to three years in the dog's bloodstream. These microfilariae enter a mosquito when it sucks blood from an infected animal. In 2-3 weeks the microfilariae develop into larger larvae in the mosquito and migrate to the mosquito's mouth.
When the mosquito bites another animal, the larvae enter the animal's skin where they live for 3 months and grow to a size of 3 inches. The larvae then migrate to the heart where they grow into adults, sometimes reaching a length of 14 inches. The time from when an animal was bitten until adult heartworms develop and lay microfilariae is about 6 months.
Medications used to prevent heartworm infections are called preventatives. The first thing to remember is that preventatives are NOT used to kill the adult worms. Special drugs called adulticides must be used to kill the adults.
When determining when to give monthly preventatives, remember, they kill larvae the animal was exposed to in the preceding thirty days. For instance, a monthly preventative given on July 1, will kill larvae the animal acquired from June 1 to July 1. The monthly preventatives do NOT work forward in time. A monthly preventative given July 1, will NOT have an effect on larvae the animal acquires later in July.
In some areas of the country where mosquitoes are present year-round, preventatives must also be given year-round. In colder climates, preventatives are started 2-3 weeks after the first mosquitoes appear and are given until after the first hard frost (when the mosquitoes are killed or hibernate).
The best program for prevention of heartworm infection includes using preventatives, performing routine heartworm testing, and reducing exposure to mosquitoes.
2007-03-07 03:13:23 · answer #1 · answered by BVC_asst 5 · 1⤊ 0⤋
Heartworms don't show up in the dog's system for 6 months. A clean heartworm test today, doesn't mean there are no heartworms; it just means they haven't ggrown to the point where they show up in the blood tests. Testing regularly makes sure the dog is free from the parasites.
Also, if your dog has been on prevenative for more than 1 year and is then found to be heartworm positive, the company that made the preventative may pay for any heartworm treatments the dog needs. So keep track of when you give the preventative and who the manufacturer is.
2007-03-07 02:57:29 · answer #2 · answered by Fetch 11 Humane Society 5 · 0⤊ 1⤋
Read www.evidencebasedvet.com
This is by a vet in Florida. Click on articles and scroll down to the one on heartworm.
This vet proves by linking you into the U.S. government's website that
1. Heartworm pills do not need to be given monthly
2. Heartworm positive dogs can be given the heartworm pills
3. Being 100% effective, there is no need to pay for a yearly heartworm test
2007-03-07 03:31:29 · answer #3 · answered by A Great Dane Lady 7 · 1⤊ 1⤋
They've seen too many cases where the owners claim they've given heartworm preventative to their dog faithfully yet still end up HW positive. This just tells them they have NOT been using it as they're suppose to.
Also, it is not 100%. It helps, but there is no guarantee a dog will not contract heartworms even if it has been on it faithfully throughout the year.
It's best to just have them tested when they go in for their annuals anyway.
2007-03-07 02:44:42 · answer #4 · answered by Pam 6 · 0⤊ 1⤋
Just in case you miss a dose. Not every dog owner keeps their dog on preventative medication year round.
My dog is on it year round but I still test her every spring- just in case. Prevention is less costly than treatment
It's especially important to do test if you are in an area that has a high incidence of heartworm,etc.
Also, if you got this dog as a puppy and started it on preventative, you need to make sure that it is still negative. Heartworm takes about 6 months to mature
2007-03-07 02:43:07 · answer #5 · answered by paris26 3 · 0⤊ 0⤋
Like the above posters said, its to make sure there is no chance your dog a contracted heartworm. Meds are usually effective, but there are still occasional cases of dogs who get it while on preventative. By the way it makes financial sense for you to pay for the test. Heatguard has a guaruntee that if your dog is on preventative, and the contract the illness, the company will pay for treatment, BUT you have to be able to prove your dog is tested yearly and that you bought the preventative.
2007-03-07 03:45:32 · answer #6 · answered by cs 5 · 1⤊ 1⤋
Because nothing is perfect and there is still a chance your dog can get heart worm, Fleas are getting stronger and heart worm strains are getting stronger. Catching it earlier is better than later
2007-03-07 09:31:24 · answer #7 · answered by katie d 6 · 0⤊ 0⤋
No preventative is 100% effective. Testing makes sure the drug is not given to a dog who is infected, which could be lethal.
2007-03-07 02:37:31 · answer #8 · answered by melissa k 6 · 0⤊ 2⤋
jst to make sure that the medication that is taking is still effective. it's like if someone took asparin for a head ache. after awhile, 500mg is not enough, they have to up it up to 750. so in the case of the heartguard, the vet has to make sure it's still working. also, dogs can get new strands of different things.
2007-03-07 02:44:20 · answer #9 · answered by hydez2002 4 · 1⤊ 2⤋
just incasue the heart gausrd doesnt work for the dog
2007-03-07 02:36:34 · answer #10 · answered by Anonymous · 0⤊ 1⤋