1
|
Monteiro C, Ferreira LL, de Paula LGF, de Oliveira Filho JG, de Oliveira Silva F, Muniz ER, Menezes KMF, de Camargo FR, de Oliveira Nonato R, Martins DB, Marreto RN, Borges LMF. Thymol and eugenol microemulsion for Rhiphicephalus sanguineus sensu lato control: Formulation development, field efficacy, and safety on dogs. Vet Parasitol 2021; 296:109501. [PMID: 34147769 DOI: 10.1016/j.vetpar.2021.109501] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 06/07/2021] [Accepted: 06/07/2021] [Indexed: 02/07/2023]
Abstract
The present study aimed to develop a microemulsion formulation containing thymol and eugenol for field control of Rhipicephalus sanguineus sensu lato on dogs, as well to evaluate its safety and the physical characteristics of the formulation. The microemulsion using thymol and eugenol (5.0 + 5.0 mg/mL) had as vehicles water, propylene glycol, polysorbate 80 and canola oil. On the next day the preparation (formulation freshly prepared) and after 24 months, the size of the microemulsion droplets, polydispersion index (PdI), organoleptic properties (color, viscosity), and presence of precipitate in the microemulsion were evaluated. For the field assay, on day -1, 10 English Cocker Spaniel dogs were experimentally infested with 200 larvae, 100 nymphs and 30 adults of R. sanguineus s.l. On day 0, after tick counts, the animals were divided into two groups: treated with the freshly prepared microemulsion (10 mL/kg), and control, which received the vehicle (10 mL/kg). Tick counts on dogs were performed daily for three more days. Engorged females were recovered from the dogs and their biological and reproductive parameters were monitored. The dogs' clinical parameters (temperature, mucosa color, and general physical condition) were evaluated daily. In addition, blood samples were collected before infestation to verify hematological (packed cell volume) and biochemical parameters (total serum protein, albumin, globulins, creatinine, urea, alanine transaminase, aspartate aminotransferase, and alkaline phosphatase). Freshly prepared and 24-month aged microemulsions had droplets with mean sizes of 30.94 nm and 27.93 nm, and PdI values of 0.214 and 0.161, respectively. In addition, no difference in the organoleptic properties and no precipitation formation were observed, indicating physical stability. Treatment with the microemulsion resulted in reduction of larvae (p < 0.05) parasitizing the dogs on day 1 while the number of nymphs and adults was not reduced (P> 0.05). In the evaluation of the reproductive biology of engorged females, the larval hatchability (%) was compromised (p < 0.05), and the microemulsion had control rate of 85.5 %. The microemulsion and its vehicles did not change the clinical, hematological and biochemical parameters of the dogs. We concluded that the microemulsion was efficient against R. sanguineus s.l. by reducing the number of larvae and affecting the reproductive parameters of engorged females, safe for dogs, and stable (physical stability) during a two-year interval.
Collapse
Affiliation(s)
- Caio Monteiro
- Instituto de Patologia Tropical e Saúde Pública da Universidade Federal de Goiás (UFG), Rua 235, s/n, Setor Universitário, Campus Colemar e Silva, Goiânia, Goiás, CEP: 74605-050, Brazil; Programa de Pós-graduação em Ciência Animal da Universidade Federal de Goiás, Avenida Esperança, s/n, Campus Samambaia, Goiânia, Goiás, CEP: 74.690-900, Brazil.
| | - Lorena Lopes Ferreira
- Programa de Pós-graduação em Ciência Animal da Universidade Federal de Goiás, Avenida Esperança, s/n, Campus Samambaia, Goiânia, Goiás, CEP: 74.690-900, Brazil; Departamento de Medicina Veterinária Preventiva, Escola de Veterinária da Universidade Federal de Minas Gerais, Avenida Antônio Carlos, Campus Pampulha, Belo Horizonte, Minas Gerais, CEP: 31.270-901, Brazil
| | - Luiza Gabriella Ferreira de Paula
- Programa de Pós-graduação em Ciência Animal da Universidade Federal de Goiás, Avenida Esperança, s/n, Campus Samambaia, Goiânia, Goiás, CEP: 74.690-900, Brazil
| | - Jaires Gomes de Oliveira Filho
- Programa de Pós-graduação em Ciência Animal da Universidade Federal de Goiás, Avenida Esperança, s/n, Campus Samambaia, Goiânia, Goiás, CEP: 74.690-900, Brazil
| | - Fernanda de Oliveira Silva
- Escola de Veterinária e Zootecnia da Universidade Federal de Goiás, Avenida Esperança, s/n, Campus Samambaia, Goiânia, Goiás, CEP: 74.690-900, Brazil
| | - Elen Regozino Muniz
- Programa de Pós-graduação em Ciência Animal da Universidade Federal de Goiás, Avenida Esperança, s/n, Campus Samambaia, Goiânia, Goiás, CEP: 74.690-900, Brazil
| | - Karolina Martins Ferreira Menezes
- Programa de Pós-graduação em Ciência Animal da Universidade Federal de Goiás, Avenida Esperança, s/n, Campus Samambaia, Goiânia, Goiás, CEP: 74.690-900, Brazil
| | - Fabrício Rômulo de Camargo
- Programa de Pós-graduação em Ciência Animal da Universidade Federal de Goiás, Avenida Esperança, s/n, Campus Samambaia, Goiânia, Goiás, CEP: 74.690-900, Brazil
| | - Rhayssa de Oliveira Nonato
- Faculdade de Farmácia da Universidade Federal de Goiás, Rua 240, s/n, Setor Leste Universitário, Campus Colemar e Silva, Goiânia, Goiás, CEP: 74605-170, Brazil
| | - Danieli Brolo Martins
- Programa de Pós-graduação em Ciência Animal da Universidade Federal de Goiás, Avenida Esperança, s/n, Campus Samambaia, Goiânia, Goiás, CEP: 74.690-900, Brazil; Escola de Veterinária e Zootecnia da Universidade Federal de Goiás, Avenida Esperança, s/n, Campus Samambaia, Goiânia, Goiás, CEP: 74.690-900, Brazil
| | - Ricardo Neves Marreto
- Graduada em Medicina Veterinária da Universidade Federal de Goiás, Avenida Esperança, s/n, Campus Samambaia, Goiânia, Goiás, CEP: 74.690-900, Brazil; Faculdade de Farmácia da Universidade Federal de Goiás, Rua 240, s/n, Setor Leste Universitário, Campus Colemar e Silva, Goiânia, Goiás, CEP: 74605-170, Brazil
| | - Lígia Miranda Ferreira Borges
- Instituto de Patologia Tropical e Saúde Pública da Universidade Federal de Goiás (UFG), Rua 235, s/n, Setor Universitário, Campus Colemar e Silva, Goiânia, Goiás, CEP: 74605-050, Brazil; Programa de Pós-graduação em Ciência Animal da Universidade Federal de Goiás, Avenida Esperança, s/n, Campus Samambaia, Goiânia, Goiás, CEP: 74.690-900, Brazil
| |
Collapse
|