Rumination-3

“Nature never did betray”

- wordsworth

Most of the veterinarians and few scientists are of the opinion that bacterial / viral proteins only can produce antibodies, but not plant proteins. It is not true. Few plant proteins also can produce antibodies. Ricin is one of the protein which is capable of inducing the formation of antibodies in the animal body. These antibodies allow the animals to withstand up to 800 times of normal lethal dose. Unfortunately, this information was not taught to undergraduate students on those days.

In my native (dry) district castor bean plants were grown in the boundaries of dry lands as commercial crop. There is ample chance for the grazing animals to trespass into the caster bean plant cultivated lands and consume first the castor bean leaves. But, invariably the landowners will drive them out before they consume sufficient quantity to produce toxicity. Consuming frequently small quantity of castor bean leaves during grazing the animals in my district develop antibodies and become immune to the toxicity of ricin even if they consume large quantity of castor bean leaves.

But, the animals in delta district are not exposed to this plant during their lifetime since this plant is not grown in the fields as commercial crop. The castor bean plants are grown in the delta area only in the garden more as ornamental plant. So, there is no chance for the animals grown in that area to consume the leaves of castor bean during the grazing as in dry districts. Due to this, the animals in delta districts are not immune to the toxin – Ricin. Whenever the plant is overgrown the owners cut and throw the branches of the castor bean plants from the garden in the public places. Unfortunately, the animals that are roaming in the streets will have a chance to consume sufficient quantity of castor


bean leaves to produce toxicity and death. Like that only the kid which consumed the castor bean leaves was brought to me. Due to lack of this information as veterinary student, I lost my first case in my practice.

Even today, no veterinarian in delta districts can save the poor animals which consume large quantity of these leaves since there is no antidote to ricin poison. However, they can be saved only by giving antiserum like treating tetanus cases. Unfortunately, no company in this country is manufacturing and marketing the antiserum for ricin toxicity.

If the animal was brought immediately after consuming the castor bean leaves there is a chance to save it by complete stomach wash. For that a well experienced vet and necessary instruments must be readily available at hand.

From my experience, I wish to record for the benefit of field vets and veterinary students that “A poisonous plant to grazing animals in one geographical area needs not be poisonous in other geographical area of the same district.”

”

Rumination-2

" Remember that the most beautiful things in the world are most useless"

Before discussing the reason for the death of the kid which consumed the leaves of castor bean plants the readers must know some basic information about the plant

Origin

The castor bean plant,(Ricinus communis), is a species of flowering plant. It is native to the Ethiopian region of tropical east Africa, The scientific name for the castor bean plant, Ricinus communis, has a much more logical derivation. Ricinus is the Latin word for tick and is the specific epithet for the Mediterranean sheep tick (Ixodes ricinus). Since the seeds looked like ticks, particularly large ticks engorged with blood it is named as “Ricinus”. Communis means common in Latin, and castor plants were already commonly naturalized in tropical and warm temperate regions throughout the world. Castor plants are very common along stream banks, river beds, bottom lands, and just about any hot area where the soil is well drained and with sufficient nutrients and moisture to sustain the vigorous growth. The roots, leaves, and seeds have a place in traditional folk remedies throughout the world.

Though the whole plant is poisonous the seeds or beans are extremely poisonous to people, animals and insects. When several insects feed on the plant, the plant protects itself by killing the insects by the presence of toxins. The seeds contain the highest concentration of poison. But, they are the source of numerous economically important products and the castor oil is one of earliest commercial products. Castor oil is a mixture of triglycerides, of which 75% to 90% is ricinoleic acid. Lesser amounts (1% to 4%) of linoleic, oleic, palmitic, and stearic acids are also found. The oil was used thousands of years ago in wick lamps for lighting. However, castor oil is commonly used as a laxative and for the induction of labor. The fast-drying, nonyellowing oil has been used in the manufacture of high-grade lubricants for industrial machinery and aircraft engines and in dyes, inks, paint, and varnishes. The castor cake or pulpy residue that remains after oil extraction has been used as animal feed and as fertilizer despite its unsuitability due to traces of toxins.

What is ricin?

Ricin(RYE-sin), is one of the most potent naturally occurring toxins, found in the castor beans. It is held among the top two or three deadliest poisons available in the world. It has been estimated that, gram for gram, ricin is 6,000 times more poisonous than cyanide and 12,000 times more poisonous than rattlesnake venom. If castor beans are chewed and swallowed, the released ricin can cause injury. Ricin can be made from the waste material left over (pomace ) from processing castor beans. It can be made in the form of a powder, a mist, or a pellet, or it can be dissolved in water or weak acid. Luckily ricin is immiscible with castor oil and this prevents contamination of the oil during its production. Ricin belongs to a class of proteins known as ribosomal inactivating proteins (RIPs). As their name suggests, these proteins interfere with the function of ribosomes, halt protein synthesis and thus induce cellular death. If enough cells die, lesions appear in the exposed tissues which can lead to organ failure and death of the victim.

As with most chemicals, whether or not a person/ animal becomes ill after exposure to ricin depends on how much ricin the person was exposed to, how long the exposure lasted, what the exposure method was (inhalation, ingestion, or injection), and other factors. In general, when the dose is the same, being exposed to ricin by injection has the greatest potential for causing illness, followed by inhalation, and then ingestion.Ricin mixed with food and used as bait is highly toxic to certain pest animals, such as some rodents and insects. A dose of 0.035 milligram (approximately one millionth of an ounce) may kill a man and even small particles in open sores and in the eyes may prove fatal.

Biological warfare

Ricin was used in many attempts of assassination all over the world.

Umbrella Murder

Ricin is said to have been used in the assassination of Bulgarian exile Georgi Maskov in London in 1978. Maskov was attacked with a specially engineered weapon disguised as an umbrella, which implanted a ricin-containing pellet into his body.

For further detail please read the following links.

http://news.bbc.co.uk/1/hi/uk/2636459.stm

http://www.portfolio.mvm.ed.ac.uk/studentwebs/session2/group12/georgie.htm

During the world war II. Ricin bombs were prepared by British army. Fortunately, they were not used. There is a report that that Ricin was used Iran –Iraq war.

Unlike other plants, the castor bean plant is gifted with a special character which only saved my village goats from the jaws of death in spite of consuming the leaves of the castor bean plant, grown in our lands. I will write a pithy remark about this in my next blog.

Rumination -1

My first failure

3.8.1959 11 a.m.

“Doctor! Please do something to save this. This Saturn has devoured the castor bean leaves, which were cut and thrown out from a roadside garden. Please treat it quickly”screamed an agitated middle aged farmer who rushed into the dispensary with a kid in his hands.

But, the kid was cheerfully masticating without evincing any toxic symptoms.

“Don’t worry. I have seen many kids who lived for years after consuming the castor bean leaves from our agricultural fields. Nothing will happen to your kid. No treatment is necessary” I said.

From his facial expression, I understood that the farmer is not happy. He was repeatedly pleading for some treatment. Since I had a firm conviction that castor bean leaves are not toxic to livestock I was stubborn in my decision. The farmer left the dispensary with reluctance.

He was the first client not only to me but also to that “Minor veterinary dispensary” which was inaugurated only 2 hours back. Though that village was not provided with any other basic amenities like school, electricity, protected water supply, etc, the minor veterinary dispensary was established by Government in a small room to protect the farm animals of agriculturists, living in the tail end of Cauvery delta region of Tamil Nadu, India. Within a week of my graduation, I was appointed as Veterinary Assistant Surgeon to the newly opened dispensary. I joined in duty that day only 2 hours before without any field experience. That minor dispensary also was supplied with very few medicines as mixtures and powders by the nearby Veterinary dispensary. No equipments other than a thermometer, a syringe with few needles and a Burdizzo castrator were supplied.

In the afternoon, I was sitting alone in the dispensary. My peon, the only subordinate, went out in search of a place for our boarding and lodging in that small village. At about 4 p.m. the same farmer came back to the dispensary with his dead kid in a basket. He accused that I have not saved his kid in spite of his repeated request.

I was in a very awkward situation. As young boy, during my daily strolling around our lands where we grow commercially the castor bean plants, I have noticed the incidence of consuming the castor bean leaves by goats and their kids belonging to the villagers. These animals lived for years without showing any toxic symptoms. But, I was not able to understand why this poor animal died. When I discussed with my senior colleagues, I was not able to get any convincing reply. I learnt the reason for the death of that kid and the secret of the survival of the kids in my village who lived for years after frequently consuming the castor bean leaves only after my post graduation in “Clinical Medicine”. I will share the information with readers in my next blog..

My Views

Dear Readers

I intend to write my experience in veterinary practice as well as my views on Veterinary Educational policy in our country from my experience as Registrar and also as Vice-Chancellor of the First Veterinary University in India. Hope you will enjoy.