dig by dog

A 1996 study with dogs investigated a growing misconception among some trainers and veterinarians that low protein diets (16 to 20% protein) can improve the behavior of hyperactive or aggressive dogs. These were dogs that had formerly been fed what was erroneously called a high protein diet (28 to 32% protein) on a dry-matter basis.

The results suggested that lowering protein in the diet is not generally useful in treating behavior problems involving territorial aggression, dominance aggression and hyperactivity. Unfortunately, but not surprisingly, a study was not done that reduced the carbohydrates (the major component of most dog foods) while increasing protein.

In a carefully controlled study, protein-starved animals were evaluated for the effects of protein depletion on various organs. Examination of the brain revealed only a 14% average protein loss, compared to gross depletion of 27-65% or more in other organs. Researchers concluded that, because it directs hunting/food-seeking behavior, the brain may have naturally evolved to be less susceptible to protein starvation.

Unfortunately, we must now cite rat studies for further data. Protein-starved experimental animals exhibited no serious learning deficits regarding responses to aversive (shock) stimuli or maze problems involving food rewards. However, the animals did have lower thresholds for electro-convulsive shock, that is, they convulsed at lower voltages than normal animals. The researchers tentatively concluded that a protein depletion of up to 14% in the mammalian brain does not appreciably affect learning, but slightly reduces excitability thresholds. This study raises interesting questions about the effects of protein, carbohydrate and fat ratios on the general level of excitability in mammals, particularly in problem dogs, many of which are excitable.

Studies on rats indicate that carbohydrate-rich diets can significantly increase levels of serotonin in the brain. Serotonin (5-hydroxytryptamine) is an essential but still poorly understood chemical neurotransmitter found in greatest concentrations in the nuclei of the medulla oblongata, which has a role in determining the general levels of excitability. What is pertinent is that the ratios between carbohydrate, protein and fat intake may produce both immediate and long-term changes in the excitability of dogs. It now remains to relate this empirically to certain behavior problems.

Jenny and I went for a walk today and stopped by The Loyal Biscuit Company to look for something to keep her warm during potty breaks. It is getting pretty cold here in Maine. She is lacking of her own coat in a big way so she needs a little help in that department. Since I had my camera with me it became a bit of a fashion show.