Another pet poisoning took place over the weekend in Río Nuevo, de Ciudad Neily. Some 16 dogs and at least six cats were victims of what appeared to be doctored meat.
The case follows a similar poisoning in Agua Caliente de Cartago where 17 dogs died.
The Servicio Nacional de Salud Animal said Wednesday that a joint investigation with experts at the Universidad de Costa Rica showed that the Cartago case involved a pesticide known as carbofuran. The substance is usually applied to field crops.
The agency also said that meat was used to deliver the poison in Cartago, too.
Before they die, the animals poisoned with carbofuran suffer excessive salivation, breathing problems, stomach pains, vision problems, heart problems and tremors as well as diarrhea. Without immediate medical help, the animal is sure to die, said the agency.
The agency cautioned that this type of chemical also is toxic to humans, so those seeking to help poisoned animals have to take care.
The agency also urged owners to keep a good eye on their pets.
Dog poisoning is not restricted to the southern zone and Cartago. There are sporadic reports of poisoning frequently in the Central Valley. The main suspects are neighbors aggravated by barking, although such crimes are hard to prove.