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Paws & Claws

Jill Bowen has practiced veterinary medicine in England and Texas. She lives in Blacksburg now, and answers local pet owners' questions every week in The Roanoke Times and roanoke.com.

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Q I thought dogs were color-blind. But can dogs see colors? I have a rescued female mutt that seems terrified of bright blue vehicles. She refuses to walk past such a car or van, pulling on the leash and cowering behind my legs. Cars and trucks of any other color are no problem.

A It is not strictly true that dogs are color-blind, but they do not have the same color vision that people do.

Dogs are more like color-blind people. For example, colors in the blue-green spectrum may appear gray to dogs. They also don't see differences between colors in the red-green spectrum region. Dogs have the greatest color discrimination in the blue region of the spectrum. They can tell red from blue and green from blue, so your dog can distinguish blue vehicles from red or white ones quite easily.

The red-green color blindness explains why dogs often can't find a red ball in the grass but can easily spot a yellow one. It is possible that your dog's fear of blue vehicles may have arisen from a narrow escape from being knocked down by a blue car or truck before you rescued her.

Q I recently acquired eight point-of-lay hybrid hens, and they have been laying now for more than five months. I noticed that seven of the eight hens were losing the feathers on their bottoms. Is the one remaining hen with feathers pecking at the bottoms of the other hens? And if so, why? We have not seen her attacking them.

A The loss of feathers on the backsides of your seven hens is unlikely to be the result of feather pecking by the remaining hen. If feather pecking were a problem the feathers would be lost on the hen's back in front of the tail or on top of the head behind the comb. It is much more likely that your hens are suffering from a lack of calcium phosphate that is needed to make the shells of the eggs.

Most hybrid hens have been specially bred to lay a lot of eggs, and yet the hens are small so they do not eat a great deal. The calcium phosphate needed to produce healthy feathers and the eggshells is stored in the bones and feathers. Because these hens are small, the bones are also smaller. These smaller bones contain less stored minerals such as calcium, so the calcium phosphate for the eggshells has to come from the feathers, especially because these hens have been laying eggs for some time.

I surmise that the hen that has not yet lost any feathers may not be such a prolific layer as the other hens, so her calcium phosphate reserves are not so depleted as those of the other hens. To correct the problem, feed the hens a good mix of layers mash, which will contain calcium phosphate in the correct proportions. Giving oyster shell is a common mistake because it contains calcium but no phosphorus and may make matters worse.

Q What other methods are there for separating fighting dogs? In the winter I don't necessarily have a garden hose available or even a spade.

A Perhaps the easiest way to separate to fighting dogs is to throw a blanket over them. This works well, especially if there is a second person present so that each of you can grab a dog as it backs out.

Failing a blanket, a large heavy coat thrown over their heads is usually sufficient. But be careful because it is easy to get bitten in the resulting melee.

A large amount of black or white pepper shaken over their noses also works well; this causes involuntary sneezing. It is impossible to sneeze and to fight at the same time. It is also easier to have a well-filled pepper shaker readily available than a blanket, especially if the fighting occurs when on a walk.