Application of hormonal subdoses at the Bai Hui acupoint for estrus synchronization in sheep

• Autor(a) principal: Souza, Diego Oliveira
• Data de Publicação: 2021
• Outros Autores: Biscarde, Carmo Emanuel Almeida, Machado, William Morais, Vieira, Renan Luiz Albuquerque, Mendes, Claudinéia Silva, Araújo, Monna Lopes de, Santana, Ana Lúcia Almeida, Barbosa, Larissa Pires
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Semina. Ciências Agrárias (Online)
• Texto Completo: https://ojs.uel.br/revistas/uel/index.php/semagrarias/article/view/40913
• topic: Acupuncture; Equine chorionic gonadotropin; Prostaglandin F2alfa.; Acupuntura; Gonadotrofina coriônica equina; Prostaglandina F2alfa.

Here, the efficiency of applying subdoses of equine chorionic gonadotropin (eCG) and prostaglandin F2 alfa (PGF2alfa) at the Bai Hui (BH) acupoint for estrus synchronization in sheep was evaluated. Thirty Santa Inês ewes received intravaginal sponges containing 60 mg medroxyprogesterone acetate for 7 days. The animals were divided into five treatments (T) (n=6): T1 (control), 132.5 ug PGF2 alfa (100% of dose) and 300 IU eCG (100% of dose), both intramuscularly (IM); T2, 39.75 ug PGF2 alfa (30% of dose) at the BH acupoint and 300 IU eCG (100% of dose) IM; T3, 132.5 ug PGF2 alfa (100% of dose) IM and 90 IU eCG (30% of dose) at the BH acupoint; T4, 39.75 ug PGF2 alfa (30% of dose) and 90 IU eCG (30% of dose), both at the BH acupoint; and T5, 39.75 ug PGF2 alfa (30% of dose) and 90 IU eCG (30% of dose) both at a false acupoint (IM, at the same location as in T1). After 12 h of sponge removal and hormone application, the ewes were subjected to monitoring for estrus and mating and ultrasound assessments of follicular growth and ovulation time every 12 h. The data were evaluated for normality and subjected to analysis of variance, considering a 5% probability. There were no differences in the percentage of animals in estrus (93.3±9.1%), interval from sponge removal to estrus onset (48.1±6.0 h), interval from sponge removal to estrus end (69.6±5.4 h), duration of estrus (24.0±4.7 h), interval from sponge removal to ovulation (73.7±5.9 h), interval from estrus onset to ovulation (26.5±2.3 h), size of the largest follicle (6.7±0.4 mm), follicular growth rate (0.8±0.1 mm•day-1), number of ovulations (1.3±0.1), and plasma progesterone levels 7 days after ovulation (9.6±2.0 ng•mL-1). The cost of the synchronization protocol per animal was US$ 4.37, 4.12, 2.96, 2.71, and 2.71 for T1, T2, T3, T4, and T5, respectively, with 37.99% cost reduction using PGF2 alfa and eCG at 30% of the conventional doses. Therefore, the application of reduced PGF2 alfa (39.75 ug) and eCG (90 IU) doses at the BH or false acupoint effectively synchronized estrus and reduced protocol cost in sheep, indicating that the conventional doses are overestimated.