[MUSIC]
The purpose of this video is to discuss, describe and demonstrate methods for
pregnancy detection in sows and gilts using ultrasonography.
This video will outline two different methods to assist producers with pregnancy
diagnosis and ways to improve the accuracy of diagnosis.
The first two methods being discussed in this video are pregtone ultrasonography
and real-time ultrasonography.
With proper use of these methods, producers can minimize non-productive
days in sows and gilts, improving reproductive efficiency in their herds.
However, before we discuss the two methods for pregnancy detection,
let's look at how an ultrasound machine works to get a grasp on how these
technologies work.
Ultrasonography uses high frequency sound waves, which are processed by a computer,
to create either a visual image or an acoustic sound, which can be utilized for
pregnancy diagnosis.
All ultrasound machines have two main parts.
A transducer, also known as a probe, which sends out and receives sound waves.
And a computer that converts the sound waves into an image or sound.
Soundwaves are emitted from the transducer into the body and
interact with different tissues present in the body.
Some tissues will absorb some or all of the sound waves and
others will reflect the sound waves back to the transducer.
Dense tissues, such as bone, will reflect most of the sound waves.
Whereas tissues containing water or fluid will absorb most of the sound waves.
In a real-time ultrasound,
fluid will appear black on the ultrasound screen and denser tissue will appear gray,
like the muscle in the uterus, or white, like that for bone.
The machine will then convert the patterns of reflected sound waves into either
visual, acoustic or electrical signals.
In the case of a real-time ultrasound,
soundwaves are converted into visual images that map out the internal organs.
Pregtone technologies use acoustic and
electrical signals to indicate the presence of fluid in the tissues.
In sows,
early detection of pregnancy is determined by fluid filled pockets in the uterus.
These pockets fill with amniotic fluid and contain the growing embryo.
In either method used, these pockets are what determines if sows are pregnant.
So now let's move on to discuss the first method of pregnancy detection using
real-time ultrasound.
Using a real-time ultrasound is a very accurate way of pregnancy diagnosis.
These ultrasounds have a screen that will display a grayscale,
real-time dissection of the sow's internal organs.
Pregnancy diagnosis can be performed using either a real time ultrasound between 22
and 30 days of gestation.
To use a real-time ultrasound, first, apply lube or oil to the probe and
place the probe under the rear flank of the animal as shown here.
This will prevent the sound waves from scattering and
serve as a medium to direct the waves at the skin of the animal.
Be sure to apply constant pressure with the probe into the flank area of the sow.
You will then need to point the end of the probe towards the opposite shoulder
of the sow as indicated here.
This is done to avoid pointing the probe directly at the bladder of the sow.
The bladder would also appear as a black, fluid-filled sac and
could provide a false positive in pregnancy diagnosis.
Let's take a closer look at the screen of a real-time ultrasound for pregnancy.
A pregnant sow's uterus will have small, black circles,
which are fluid filled pockets, in a gray tissue.
This tissue is the uterus of the sow and the pockets are the amniotic sacs.
In this video of a pregnant sow,
you can see black circles with small developing embryos inside.
It is important to note that there are multiple circles or pockets of fluid and
not just one, which could be the bladder.
In this video, the uterine tissue appears completely gray with no fluid filled
pockets indicating an open sow.
Determining pregnant sows is much easier than open sows.
So be sure to move the probe around before calling a sow open.
This may take some practice.
Let's move on to the second method using a pregtone.
Most pregtone technologies utilize a sound box that will beep whenever fluid pockets
are detected by the ultrasound.
In order to accurately say if a sow is pregnant,
a long consistent beeping sound should be heard.
This technology can be used for
pregnancy diagnosis as early as 18 days of gestation.
However, manufacturers recommend rechecking sows around 30 days
of gestation.
To use a pregtone, follow the same instructions as for
the real-time ultrasound.
And that is to apply lubricant, place the probe under the flank and
point it towards the opposite shoulder while applying pressure.
Here, you can hear the pregtone beep as the technician checks a pregnant sow.
[SOUND] Remember that a quick beep does
not necessarily indicate pregnancy.
So make sure you can get a consistent beep.
If the probe is pointing at the bladder, the ultrasound will beep and
indicate a pregnant sow, which may or may not be the case.
Here, we're using both the pregtone and
a real-time ultrasound together to demonstrate this common mistake.
If you hear the pregtone beeping, indicating a pregnant sow.
However, the image of the real-time ultrasound reveals you're pointing at
the bladder.
[SOUND] We have just discussed the use of two
ultrasound technologies used for pregnancy diagnosis in swine.
So let's recap how these technologies work.
For both ultrasounds, be sure to apply plenty of lubricant to directly contact
the probe to the animal's skin just under the rear flank of the sow.
Apply pressure and point the probe towards the opposite shoulder.
Be sure to avoid pointing at the bladder for both technologies.
For the pregtone, you wanna be sure and
hear consistent beeping tone to assure that the animal is pregnant.
For the real-time ultrasound, look for small, black circles in the gray tissue.
These ultrasound machines can both accurately determine pregnancy between
20 and 30 days of gestation.