Óleo de peixe associado ao ácido ascórbico no diluidor para criopreservação de sêmen caprino

Abstract

The study aimed to evaluate the effect of fish oil inclusion associated with ascorbic acid in the thinner for goat semen cryopreservation. They used two males Boer aged 18 ± 1.19 months and 60.12 ± 2,34Kg and body condition of 3, raised in semi-intensive system. Semen samples were taken twice a week, the artificial vagina method. After collection, the evaluated ejaculates how the physical and morphological aspects, according to the Brazilian College Animal Reproduction (CBRA, 2013). After evaluation, the formation of a pool, followed by the split into five groups (G): G1 (control): yolk-citrate extender (Mies Son, 1987) plus 0.05% ascorbic acid (Synth®) and G2, G3, G4 and G5: yolk-citrate extender plus 1.0; 2.0; 3.0 and 4.0% fish oil (Nature Made®) + 1% sodium lauryl sulfate and 0.05% ascorbic acid, respectively. The semen was cryopreserved in TK 3000® freezing machine using the curve for goats. After thawing, they were conducted physical evaluations of post-thaw semen and additional testing slow heat resistance (TTR), hiposmotic test (HO), acrosome integrity and compression of sperm chromatin. Data were evaluated by regression analysis at 5% significance. There was linear increase (P <0.05) for post-thaw motility. There was no difference (P> 0.05) for post-thaw effect, with an average of 2,00±0,24. The TTR there was no difference (P> 0.05) between treatments for sperm motility and vigor between times 5-180 min as the initial and final means of 62,17±12,13 and 14,29±10,55, for motility and 2,00±0,52 and 0,49±0,44, to force. There was no difference (P> 0.05) between treatments in HO, with an average percentage of reactive sperm 23.5±5.96%. For acrosome integrity was no difference between treatments (P <0.05) for intact acrosome and acrosome irregular, with increasing and decreasing linear behaviors, respectively. There was no difference (P> 0.05) in the compaction of chromatin, with percentage of 97.06 ± 1.17% of full chromatin. Thus, the inclusion of up to 4% fish oil plus 0.05% ascorbic acid in diluter for goat semen cryopreservation improved sperm viability after cryopreservation by means of motility and acrosome integrity.