Bovine biology series
Part - 46 Life cycle (7/8)
We are winding down the life cycle of the cow in these final two articles of this long, 48 part series. And so let us delve into the end of life, knowing that in the broader perspective, the line between life and death is hard to define, for almost as certain is every breath defined with the rising and falling of the diaphragm, then when the breathward rhythm ceases, another takes its place, in a different form, yes, but life longs to keep going.
I came to this realization from my boyhood days on a farm, when placing manure out of the barns into the fields, and new plants grew from old plants once moved through a cow. In the animal kingdom, such recycling does occur as well.
I am certain of this too, that we do not fully understand why an animal ages and soon dies, except that inherent in the biological world there must be certain genetic signals that may be involved, such as in cellular replication, a certain strand of DNA can be repeated just so many times, and then it is finished. In this manner, cellular death occurs because DNA drive cellular function, such as enzyme production, and when enzymes cannot convert nutrients into fuel, the flicker of energy within that cell defining life, goes out.
In fact life may be thought of as consuming energy so that entropy (loss of structure) is delayed. Not stopped altogether, but delayed. Thus somewhere in a chromosome is a gene that contains such an aging strip of nucleotides that serve as a marker. A marker determining replication numbers.
I have wondered about a more global perspective of life and death, indeed, one that knows that within a finite space, there is only so much energy that can be made (photosynthesis) and thus a limited amount of respiration (oxidation) arising only afterwards. Could it be that that life is based on the inherent knowledge that eventually, an entity such as a plant or animal must die so that further life may continue, as if the big picture here is that life will endure?
Another relationship exists between the mind and body, not dualism at all, but one in itself. And that is the tug of enduring life that beckons higher animals, cows included, to long for life. The mind is the most powerful organ in the body, for its control through nervous pathway and hormonal control overrides much of what can be considered life threatening, to a point. That is, some animals are just determined that they will keep going, and that inner strength is mind seated, conscious thought, and chemically defined.
So even though at the cellular level, a bit of DNA is marking time, the mind resists, and resists the best that it can if it so determines that the body will continue to metabolize nutrients, discharge gas, move musculature, beat an aging heart, draw the breath of life inward, and let the flicker of life endure....for a while longer.
I recall very plainly older cows in our herd. They walked slowly. They usually knew how to find the spot in the barn where the best air was. They knew when the feed truck was coming. And they knew how to get to the water trough in front of the younger cows. In essence, they owned a sense of wisdom that younger cows did not. Yet I recall only a few cows that ever died of old age on our farm.
Why?
I am certain that environmental influences took a hold of their body first, as if in defining stress, we defined the longevity of cows’ life. My point is, of course, that over time, the stressful acts that came with housing and confinement systems and disease could not keep a cow out of harms way.
For instance, the debilitated effects of disease can overcome the healthiest of animals; sometimes quickly as if a silent invader has entered the body and the hellish wrath is spread over cells. Tissues shut down partitions of the body many hours before the immune system can get into the act of fighting the invader. A Coliform infection comes to mind.
Sometimes the cascading events that are begun simply overcome the animal, one organ system at a time. A cow calves, yet the uncoupling of a fetal placenta is slowed because the chemical mix, bloodstream carried, does not contain the proper metabolite so that the enzyme can be made so that the protein cannot be cleaved so that the cell does not physically move ions across a membrane; the tissue is static, holding on. Meanwhile, the cow lays down in a hospital string with a wide range of microbes. They enter her reproductive tract, move through the vagina and make their way into the still-large uterus where a decaying membrane is still adhered to uterine walls.
A symbiotic relationship is established, in that the microbes find a place that is dark, warm, moist, and full of nutrients. They quickly establish toxins; a sepsis is now apparent. Within a few hours the sepsis breaches the local area in the uterus and once in the bloodstream, travel to the heart. And in another hour, all parts of the body have such septic residues in them.
The cow is overwhelmed, her temperature rises, and by morning she cannot easily breath. One by one, organs shut down until finally, the racing heart fails and she is dead.
Another condition may be poor air quality, the silence of which is unseen, for the lung tissue is dying little by little as particulate matter erodes the delicate membrane making up the soft tissue that take in oxygen and release carbon dioxide and water. The cow dies a little every day, doesn’t she? Soon she is sold, an involuntary death awaits her for she has been unable to gain weight, her production goes down and she leaves the herd.
Thus, in aging, a positive environment can play a huge role in delaying the costs of aging, for while we may keep a cow healthy for many years, we cannot possibly remove all potential maladies from her day to day life. But we can sure try. When we do, then we let the life of a cow somehow be higher in quality. That is a worthy objective, isn’t it?
The benefit is, of course, more production, more pregnancies, and in both, a greater degree or measure of efficiency.
Ultimately, a cow is better for our care, for our wise use of placing her into an environment that reduces stress, disease, and malnourishment. But she will age, as we all do.
But the flicker of life, that simple made more complex, the building of something from mere atoms, will endure, and endure onward. In every cell and that which becomes tissue and in a limb or cavity all is stretched over the skeletal bones of a carriage, until another animal begins again.
In this way, life endures, and aging is, I am sure, merely a part of the journey.
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