Frankly put, I think it has no substance. I will say that an animal that has been in the pasture for an hour in the hot sun may display a faster heart rate than one that has been sitting and chewing the cud. Also an animal that has just fed may also and one that has been subjected to the harassment of a calf may also show faster heart rates. Clouds of flies may elevate the rate along with running or simply walking a long distance to the barn! There are way too many variables in any given animal that can elevate the heart rate. Simple indigestion may do it. An infection of the gut may do it. Bloating may do it - do you see my point! Any test conducted MUST be free of anything that may provide questionalbe results, period! Otherwise it is not a reliable test.
PrP, normal prion and PrPc and PrPsc [abnormal Prion] are most certainly excreted through the urianl tract. Human CJD patients excrete PrPsc in their urine in various amounts. It is not generally consistent with the level of infection that we see the prion number rising, but more the length of time that the individual has been infected. Having said that, we see more concentrated/higher levels at the first morning pass than we do at say lunchtime or afternoon and evening. The bladder collects more urine normally when the individual is sleeping. We all excrete normal prions in our urine - every one of us walking the earth does it daily. We have shown that healthy indivduals will show low counts of normal prions on some days and then higher counts of other days. Some cultures show markely low amounts of normal prions - a section of China for example wherein the local population consistently show low trace amounts of nromal prions in their urine. This led the researcher to look into diet and other contributing factors. THe level of prion descetion was the same throughout the area in all ages of the population which led the researcher to focus almost exclusively on the local food produced and the diet of the people. We are still waiting for the data. Age in animals and humans will have an affect on the prion levels if that individual has been infected for some time. In humans, the progression rate of the disease is marked in decades generally. In animals in can be marked in months or low number years. The prion itself is self-replicating. The isoform protein will typically form itself into clusters within the brain and other parts of the central nervous system where it will multiply and in the brain it will manifest itself in the form of vacuoles [the typical description being the swiss-cheese effect] and it is these clustered prions in the vacuoles that bring about the disruption of the normal brain function. Depending on precisely where in the brain that the vacuoles occur, the level of symtomatic disorder may be markedly different than if the clusters were located in other parts of the brain. Typical symotoms in humans and animals at the onset of these symtoms is memory loss, ataxia[ shuddering, shaking] vision loss, mood changes, muscle movement loss or involuntary movements. The list of afflictions seem to endless for those animals and humans infected with this hideous protein.
Evidence of the urine contaminated with various levels of PrPsc [abnormal/infectious prions] can be found in the Archive Vaults at VLA Weybridge. They have collected urine from BSE infected cattle and Scrapie infected sheep for years now and it is available for lab testing. They have catagorically shown that infected aniamls excrete infectious prions along with normal prions. The level of infection will vary somewhat from one animal to another as it does in humans infected roughly at the same time. However, the time of infection generally will not dictate the amount of PK resistant PrPsc found in any individual animal or human. Some animals and humans will take far longer to progress through the stages of infection that will most certainly end in the death of that individual and some will actually outlive the disease. That is part of what makes this damn thing so hideous. I hope this answers your questions. Ron.