Introduction

A survey on antiparasitics marketed in Latin America by the end of 2015 has been carried out. A total of 2602 antiparasitic products (ectoparasiticides, anthelmintics and endectocides) for livestock (including horses), dogs and cats have been reviewed, marketed by 173 animal health companies. The survey covers more than 90% of all the products available in the region. This article offers a summary of the results for livestock (cattle, sheep, swine, poultry and horses) obtained in this survey.

Animal Health Companies active in Latin America included in the survey

Six global multinational companies are included in the review: Bayer, Elanco, Merial, MSD Animal Health, Virbac, and Zoetis. These companies have been traditionally involved in the discovery and development of new endectocidal, ectoparasiticidal and/or anthelmintic active ingredients (excepting Virbac; Elanco only after acquiring Novartis AH).

The remaining 167 companies reviewed are mainly domestic companies and a few European ones that have established affiliates or subsidiaries in Latin America, e.g. Calier, Ceva, Bimeda, Fatro, Vetoquinol, etc. Antiparasitic products marketed by these companies in Latin America (not those marketed in Europe or elsewhere) have been included in this survey. Only companies with at least three antiparasitic products have been considered for this survey. Table 1 shows the number of companies in each of the major countries included in this survey, whereby many companies are active in numerous Latin American countries.

Out of the recorded 2'602 antiparasitics, 1'906 are approved for use on livestock and 797 for use on pets, whereby numerous livestock products are approved for use on dogs and cats as well, particularly topical products (dips, sprays, dressings, etc.) as well as anthelmintic additives and drenches. The antiparasitics for use on pets are analyzed in another article in this site (link).

From the 1'906 antiparasitic products for livestock recorded in this survey, only one, Zolvix, contains an a.i. (monepantel) that is still patent-protected. Zolvix is available in a few countries for exclusive use on sheep. This means that 99.95% all antiparasitics for use on livestock are basically generics.

Delivery forms of livestock antiparasitics by target species

Injectables are the most used delivery form of livestock antiparasitics, followed by drenches and dips&sprays. This is due to the fact that macrocyclic lactones, the most used chemical class, are delivered mostly by injection, and that other injectable anthelmintics (e.g. closantel, levamisole, ricobendazole, etc.) are very popular in Latin America. Table 2 shows the number of products for each major delivery form and target species.

* Same product often approved for more than one target species

Chemical classes of livestock antiparasitics by target species

Macrocyclic lactones (MLs) are the most used chemical class of antiparasitics in livestock in Latin America: about 1/3 of all products contain a ML. They are also used in poultry, an indication not approved in the EU the USA and many other countries. Second most used chemical class are the benzimidazoles (BZMs).

Surprisingly, organophosphates (OPs) are the most used chemical class among the ectoparasiticides, before the synthetic pyrethroids (SPs). This is due to the fact that many SPs are used in mixtures with OPs to overcome very strong and frequent SP-resistance, and to the abundant used of OPs in dressings and ear-tags.

Table 3 summarizes the number of products for each chemical class and target species.

* Same product often approved for more than one target species

Macrocyclic lactones (ML) used in livestock antiparasitics

Ivermectin is the most used ML a.i. at all in Latin America. And the classic 1% injectable (Ivomec) is the most used formulation at all as well, with hundreds of different products. However, there are also numberless local innovative versions of ivermectin products that differ from the original products, both by its ivermectin content (1,1%, 1,2%, 2%, 3.15%, 3.5%, 4%) or by its combination with aminoacids, minerals, vitamins, growth promoters, or other anthelmintics (e.g. closantel, nitroxynil, etc.).

Interesting is also the abundance of generic doramectin products, mostly in the form of the 1% injectable, which is quite appreciated in Latin America for its excellent efficacy against human bot flies (Dermatobia hominis). Products with generic doramectin are also approved for use on horses in several Latin American countries. Eprinomectin injectables have been marketed in Latin America before Merial introduced LongRange (5% eprinomectin) in the USA. Tables 4 and 5 show the number of products with MLs marketed in Latin America for livestock found in this survey, Table 4 by target species, Table 5 by delivery form.

  * Same product often approved for more than one target species

Anthelmintic active ingredients used for livestock in Latin America

Levamisole is the non-endectocidal anthelmintic a.i. ingredient most used in cattle, sheep and swine in Latin America, and it is mostly used as an injectable. This is in strong contrast with many other important livestock markets (e.g. USA, EU, Australia) where levamisole use is nowadays rather scarce and very seldom as an injectable. Albendazole is the second most used anthelmintic compound in cattle and sheep, followed by fenbendazole and closantel. Such an abundant use of closantel is also particular for Latin America, in contrast with the USA, the EU and Australia, where it is rather scarcely used. Many BZMs used in drenches are also approved for intraruminal injection (mostly in cattle), also a popular use in Latin America that is quite unusual elsewhere. Mixtures of levamisole and BZMs with MLs or with closantel are quite popular in Latin America too.

Fenbendazole is number anthelmintic a.i. in horses, followed by praziquantel, which is rather poorly used in cattle or sheep. However, praziquantel, a tapeworm-specific active ingredient, is mostly used in combination with a nematicide (e.g. MLs, BZMs, etc.).

For poultry, levamisole and fenbendazole are the most popular anthelmintics, almost exclusively used as additives for food or drinking water.

Tables 6 and 7 show the number of products with the most frequent anthelmintics marketed in Latin America, by target species and by delivery form, respectively.

 * Same product often approved for more than one target species; many products with more than one active ingredient.

Ectoparasiticidal active ingredients used for livestock in Latin America

Cypermethrin is by far the leading ectoparasiticidal a.i. in Latin America, this in spite of the very frequent and strong resistance of many ectoparasites to SPs (e.g. cattle ticks, horn flies, etc.). Permethrin, which is widely used in livestock in the USA and elsewhere is almost ignored in Latin America. Cypermethrin and other SPs are often used in pour-ons, dips, or sprays in mixture with OPs precisely in an attempt to overcome resistance.

Number two ectoparasiticidal a.i. is dichlorvos, but most products with dichlorvos are wound dressings that are used in rather small amounts.

Amitraz, almost exclusively as a concentrate for dipping and/or spraying is the third most used ectoparasiticide. With the spreading and increasing of SP resistance, amitraz has experienced a remarkable revival for tick control on cattle.

Tables 8 and 9 show the number of products with the most frequent ectoparasiticidal compounds marketed in Latin America, by target species and by delivery form, respectively.

  * Same product often approved for more than one target species; many products with more than one active ingredient.