Archived Newsletters

 
In Memory Of Pets Newsletter
September 2003


Untitled Document

We have gotten so many positive responses for our

"In Memory Of Pets Newsletters".

In dealing with Pet Loss Grief and Pet Loss Support, there
are many resources on the site to help in dealing with the loss of our beloved ones.


This Month's September Newsletter in Pet Wellness:

"How Well Do Dogs See"


Dog have good eyesight but if differs from ours in several respects. For many years it was believed that they had no color vision and lived in a totally black and white world.
It is now know that this is not the case, but color is not particularly important to them. Their ratio of rods to cones on the retina of the eye favors the rods much more than ours.
Rods are useful for black and white vision in dim light. Cones are employed in color vision. The "rod-rich" eyes of the dogs are therefore specially adapted to a daily cycle that favors dawn and dusk as the periods of major activity. This is called a crepuscular rhythm and is the typical mode for the majority of mammals. Humans are usually diurnal, and therefore not typical mammals as far as vision is concerned.

The small number of cones in the eyes of dogs reveals that, although they may not revel in Technicolor excitement of the human kind, they must be able to see at least to some degree of coloration in their canine landscape. As the great eye-expert Gordon Walls so eloquently expressed it, "To any such semi nocturnal, rod-rich animal (as a dog) the riches of the spectral lights could at best appear only as delicate pastel tints of uncertain identity." Quite so, but pastel tints are better than none, and it is pleasant to think that our canine companions can share with us at least some degree of color appreciation as we walk tighter throughout the countryside.

In the dim light, dogs have the advantage over us. They have a light-reflecting lay called the tapetum lucidum at the back of their eyes, which acts as an image-intensifying device enabling them to make more us of what little illumination there may be. As with cats, which possess the same device, it also make their eyes shine in the dark.

Another difference between our eyes and theirs is that they are more sensitive to movement and less so to detail. If something stands still when at a distance from them, it becomes almost invisible. This is why so many prey species "freeze" and stand motionless when they become alarmed, before trying to flee. Tests have proved that if a dog's owner remains motionless at a distance of three hundred yards, the animals cannot detect him. If, on the other hand, a shepherd is one mile distant but making bond hand signals, these can be clearly seen by the sheepdog. This sensitivity to movement is of paramount importance during the long chases when wild dogs are on the hunt. Once the prey is fleeing, the dog's eyes are their peak of performance. The hunting breed dog has a much wider field of vision. A narrow-headed breed like a greyhound has a visual range of 270 degrees. A more typical dog has a range of 250 degrees. Flat-faced dogs have slightly less. But they have more than human beings, whose visual field is only 180 Degrees. Although this means that dogs can detect small movements over a much wider slice of the landscape, they have to pay for this with a narrower range of binocular vision, a range that is only half the width of ours. So we are better at judging distances than they are.


Please Note:

As always your Veterinarian is the best source of information and
treatment for questions or problems that may exist.

If you have any suggestions or comments or would like to add to
our "Monthly Newsletter",


please e-mail:

Carole Miller
or
John Mingo

"Our Thank You To All"

WE want to thank all our volunteers and special folks who have shared their
open feelings in support and caring in responding to others in our "Guest Book"
and our "Message Board" and for the continued support for all that
In Memory Of Pets has to offer from our hearts..

Bless all who come to "In Memory Of Pets" in sharing loving feelings
for their beloved ones.

John, Carole and Staff



* Should you wish to make a contribution you may do so to:
In Memory of Pets
278 Cedar Road
Hershey, PA 17033
Attn: Kenneth L. Miller Secretary/Treasurer

*Or use on our online Secure site:

http://www.in-memory-of-pets.com/donations.asp
(Our"Thank You" page will give you a link for the information needed for sending
your free gifts to you from our hearts before
you leave the secure site.)

*Please Note: A Certificate of Appreciation is sent out with each donation.
When sending donations please let us know your correct name to be used on the certificate.
Stop by and visit Ken's "Gallery"

Http://kmiller.net-artworks.com/Ken/home.htm
Ken Miller
kmiller@psu.edu
E-Mail>> Ken Miller