R-12 is a registered veterinary medicinal product containing nicarbazin as the active ingredient. Nicarbazin has been used around the world as a coccidiostat for broiler chickens since the 1950s. Coccidiostats are added to the feed of broilers to prevent coccidiosis, a common intestinal infection in birds. They are administered until the last days of the chickens’ life, which means that they are safe in regard to human consumption.
The use of nicarbazin as a contraceptive is relatively new. Nicarbazin is not a classic contraceptive. Unlike progesterone, a hormonal contraceptive, nicarbazin metabolises in the body very quickly. Once nicarbazin is absorbed, it immediately breaks down into 2 parts: DCN, the active part, and HDP, which ensures it is absorbed by the bird’s intestines.
Regulatory authorities such as the FDA and EPA in the United States, the EFSA in the EU, and the MAFF in Japan have approved nicarbazin for use as a veterinary medicine in food-producing animals, as well as a contraceptive.
Nicarbazin has been extensively studied over the years, and these studies have looked at the impact it has on the environment. Multiple research has shown that, within realistic amounts, nicarbazin is non-toxic and safe for humans, animals and the environment. There is no risk of secondary poisoning. Some leading sources are highlighted below. The articles referenced are available as an attachment at the bottom of the page, or can be viewed online via the attached links.
The European Food Safety Authority (EFSA) conducts safety studies and provides independent scientific advice on risks in the food chain. The articles below explain the effect and safety of 3 coccidiostats that contain nicarbazin as the active ingredient: Koffogran, Maxiban at Monimax. The articles can be viewed online via the EFSA website.
Koffogran is a registered veterinary medicine (coccidiostat) for broiler chickens. Active ingredient: nicarbazin.
Maxiban is a registered veterinary medicine (coccidiostat) for broilers. Active ingredients: nicarbazin and narasin.
Monimax is a registered veterinary medicine (coccidiostat) for broilers, laying hens and fattening turkeys. Active ingredients: monensin sodium and nicarbazin.
OvoControl® is the North American equivalent of R-12. The nicarbazin concentration in OvoControl® (0.50 g/100 g) is 6 times higher than the nicarbazin concentration in R-12 (0.08 g/100 g). OvoControl® is used as a contraceptive for pigeons. The company behind the brand, Innolytics LLC, published an article on the secondary toxicity of nicarbazin, i.e. its effect on others. The University of Nebraska also published a publication on the use of OvoControl® as a contraceptive for wild animals, including city pigeons.
Source: University of Nebraska
This scientific article takes a closer look at the molecular action of nicarbazin and examines how nicarbazin affects egg production and hatchability.
Source: Research Gate
Barcelona (Spain) has been successfully using R-12 to control the city’s pigeon population for years. An explanation of the effect and safety of nicarbazin can be found on the city's website:
Source: City of Barcelona website
|EFSA | Scientific Opinion on the safety and efficacy of Koffogran (nicarbazin) feed additive for fattening||302.13 KB|
|EFSA | Scientific Opinion on the safety and efficacy of Maxiban® G160 (narasin and nicarbazin) for chickens for fattening||253.13 KB|
|EFSA | Safety for the environment of Monimax® (monensin sodium and nicarbazin) for chickens for fattening (...)||1.28 MB|
|Innolytics LLC | The Secondary Toxicity of OvoControl® (Nicarbazin) in Birds||228.06 KB|
|University of Nebraska | Review of issues concerning the use of reproductive inhibitors (...)||477.24 KB|
|Molecular Effects of Nicarbazin on Avian Reproduction||137.88 KB|
|Ajuntament de Barcelona | The product nicarbazin||197.6 KB|
Nicarbazin, the active ingredient in R-12 is safe:
R-12 is registered as veterinary medicine for city pigeons.