Cl-synch: protocolo alternativo para inseminação artificial em tempo fixo em búfalas, criadas em sistema extensivo na Amazônia

Abstract

Despite technological advances in the management of buffalo ranching and breeding techniques, there is little use in practice for buffaloes in extensively breed. The development of synchronization protocols, which reduce the stress of restraint and reduce costs, contribute to increasing the use of TAI in the buffalo herds. The experiment aimed to evaluate a method of synchronization and TAI compatible economic and practical with extensively breed. The experiment was conducted at three different farms in two lowland region in the state of Amapá (Experiment 1 and 2) conducted in the favorable reproductive season. The third in the state of Pará in artificial pasture land held in the unfavorable season. We used 208 lactating crossbred buffaloes Mediterranean / Murrah ages varied from 2.5 to 10 years with a history of postpartum period ≥ 60 days. Mothers who bore a corpus luteum was applied 2.0 ml intramuscular prostaglandin (PGF2α) (150μg/D-cloprostenol) on Day 0 = D0. Seventy two hours later (Day 3 = D3), were performed gynecological exam to confirm the presence of mucus and uterine contractions, and therefore, were inseminated immediately received 1.0 ml (100μg) of GnRH IM, with semen from different bulls. The diagnosis of pregnancy was performed between 45-90 days, through rectal palpation. CL-Synch provided an average pregnancy rate of 42.79%. Significant effect of variables: the presence of uterine contractility (χ ² = 10.9891, P = 0.0009), mucus (χ ² = 10.9891, P = 0.0009) and body condition (χ ² = 20.2247, P = 0.0005). The presence of mucus and uterine tone as shown excellent signs of a growth response and follicular differentiation and ovulation to hormonal stimulation. The relationship between bull and pregnancy rate was not statistically significant (P = 0.1684), suggesting uniformity in the quality of frozen semen from the same plant. We conclude that CL-synch is promising and its benefits are concentrated in management and cost containment, as it enables the restraint only twice, when compared to other protocols that need to contain four or more times, significantly owering stress.