Nicarbazin

Key takeaways

Nicarbazin belongs to chemistry; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Nicarbazin to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Nicarbazin from memory before moving on to harder problems.

Reference excerpt

Nicarbazin is a coccidiostat used on meat chickens. It is also used as a contraceptive for population control of Canada geese and feral pigeons. It is also a wide-spectrum anti-parasitic drug approved for veterinary use, effective on Toxocara canis, Toxascaris leonina, Ancylostoma caninum, Uncinaria stenocephala, Trichuris vulpis, Dipylidium caninum, and Taenia sp. and Mesocestoides sp.. Known brand names for specific countries include:

Carbigran (the United States) Ceva Nicarbazin (South Africa) Cycarb (New Zealand) Keymix (Australia) Koffogran (South Africa) Kofozin (Israel) Nicarb 25% (the United States) Nicarbazin (Israel) Nicarbazin Elanco (the United States) Nicarbmax 100% (New Zealand) Nicarmix (the United States) Ovistop (Italy and Costa Rica) OvoControl (the United States) PhiCarb (Australia) R-12 (Belgium) From the chemical point of view, nicarbazin is an equimolar complex formed by 1,3 - bis (4- nitrophenyl) urea and 4-6 dimethyl-2- (1H) - pyrimidinone also called 4,4'-dinitrocarbanilide (DNC) and 2-hydroxy - 4,6 dimethylpyrimidine (HDP). The DNC represents the biologically active part of the complex, but to be absorbed it must be bound to the HDP. Because of its hydrophobic nature, the DNC alone is poorly absorbed and has a limited "biological availability" so, following oral administration, it would be eliminated without being absorbed. The DNC therefore requires HDP to be absorbed and to reach a plasma level that allows an effect in the target species. Following oral administration, nicarbazin rapidly dissociates in vivo into its two HDP and DNC components, which follow different routes of excretion: 95% of HDP is rapidly eliminated with urine, while DNC remains longer and is eliminated predominantly with feces. Metabolism and depletion of the two components have been studied extensively with the use of carbon-14-labeled nicarbazin. Following oral administration, nicarbazin rapidly dissociates in vivo into its two components HDP and DNC, which are absorbed through the intestine, then passing into the blood, and following different routes of excretion. The HDP is excreted more rapidly than the DNC, mainly through the kidneys via the urine, while the DNC is absorbed more rapidly than the HDP and is excreted more slowly than the latter through the liver, via the faeces. No significant residue of either component is noticeable in any fabric after 7 days. DNC accumulates in eggs and normally the concentration of DNC in eggs is less than 5 ppm. The two components HDP and DNC do not undergo metabolism in vivo and in vitro, except for the formation of derivatives structurally similar to nitroaniline. However, this possibility appears extremely remote, achievable only in the laboratory, in particular chemical-physical conditions (high temperature in a strongly acid environment). Of the two components of the nicarbazin molecule, the DNC takes on a significance from a toxicological point of view as it remains longer in the body. The DNC molecule was therefore considered as a marker compound in residue studies.

Activities Nicarbazin, present long enough in the world market, is the product of first choice as coccidiostatic, due to its safe use, in the breeding of broiler. Known brand names for specific countries include: Carbigran (United States); Ceva Nicarbazin (South Africa); Cycarb (New Zealand); Keymix (Australia); Koffogran (South Africa); Kofozin (Israel); Nicarb 25% (United States); Nicarbazin (Israel); Nicarbazin Elanco (United States); Nicarbmax 100% (New Zealand); Nicarmix (United States); PhiCarb (Australia) The use of nicarbazin as a coccidiostat has shown, even if in a completely reversible form, an inhibiting effect on the productive and reproductive functions of laying hens, with a consequent reduction in egg production and their weight as well as a decrease in hatching capacity. The depressive effects on ovulation found in poultry have formed the rational basis for the development of some preparation, containing nicarbazin, used for birth control in the population of stray pigeons. Known brand names for specific countries include: Ovistop (Italy); OvoControl (United States); R-12 (Belgium) Nicarbazin is also a wide-spectrum anti-parasitic drug approved for veterinary use, effective on Toxocara canis, Toxascaris leonina, Ancylostoma caninum, Uncinaria stenocephala, Trichuris vulpis, Dipylidium caninum, and Taenia sp. and Mesocestoides sp..

Coccidiostatic activity Nicarbazin is active on some species of Emeria with different sensitivity. Unlike other coccidiostats, nicarbazin rarely presents resistance phenomena towards the most common coccidioses such as those supported by Emeria tenella. The dose of nicarbazin generally used in the prevention of cecal and intestinal coccidiosis of chickens is 125 ppm in feed. Nicarbazin is often used in combination with ionophoric antibiotics to increase the spectrum of activity and reduce the phenomenon of resistance.

… excerpt ends here. Continue reading the full article.

Worked examples

Example 1 — a first encounter with Nicarbazin

Start with the simplest possible case. Write down what Nicarbazin claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In chemistry, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Nicarbazin before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Nicarbazin ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Nicarbazin

In research: Nicarbazin appears in chemistry research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Nicarbazin in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Nicarbazin is common in secondary-school and first-year university syllabi. It links to neighbouring topics 4-Nitrophenyl compounds, Antiprotozoal agents, Pyrimidones, so understanding it makes those chapters shorter.
In everyday life: Look for Nicarbazin outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

How to study Nicarbazin in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Nicarbazin means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Nicarbazin out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Nicarbazin in simple terms?

Nicarbazin is a coccidiostat used on meat chickens. It is also used as a contraceptive for population control of Canada geese and feral pigeons.

Why does Nicarbazin matter?

Because it connects several chemistry ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Nicarbazin?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Nicarbazin.