Use of alternative diluent ACP-Lact® and coconut water powder (ACP) in cryopreservation of goat semen and fixed-time artificial insemination (FTAI) in half-breed goats.

The aim of the present study was to evaluate semen cryopreservation with ACP-Lact® diluent, which consists of coconut water powder (ACP) added to goat milk powder. After thawing, the samples were evaluated for sperm kinetics, membrane evaluation and in vivo insemination. For cryopreservation, a pool was made with the ejaculate of six goats, diluted in four equal aliquots for the respective treatments: T1 (ACP-Lact®); T2 (ACP-Lact® 50%); T3 (ACP + 2.5% egg yolk) and T4 (Tris + 2.5% egg yolk). After dilution of the treatments, the samples were placed in 0.5 ml straws and chilled at a rate of -1.07°C/min. After reaching 4°C and stabilizing for one hour, the straws were placed in nitrogen vapour at -60°C for 15 minutes and then immersed in liquid nitrogen (-196ºC). The straws were thawed in a 37°C water bath and kinetic assessments were performed immediately using a computerized semen analysis program (CSA), viability (EN), membrane functionality (HOST), mitochondrial activity (DAB) and DNA integrity assessment of spermatozoa. For the in vivo experiment, ten goats were inseminated, divided into two groups of five goats each, G1 inseminated with ACP-Lact® and G2 with ACP, by fixed-time artificial insemination (FTAI). Regarding the kinetic parameters, the ACP-Lact® treatment showed higher progressive motility (PM) and sperm velocity than the other treatments (36.77%). In the VSL parameter the ACP-Lact diluent was superior to ACP and Tris. In viability the treatment with ACP-Lact® was superior to the treatment with Tris, 95% and 83% respectively. In FTAI two goats were born out of the 5 goats inseminated with ACP-Lact®. It was concluded that the use of ACP-Lact® for cryopreservation of caprine semen is efficient in maintaining seminal parameters during thawing in vitro and in vivo and proved to be a good alternative extender for the caprine species.

Extra Virgin Coconut Oil as a Cryoprotector for Cryopreservation of Caprine Semen.

The study aimed to evaluate the effect of powdered coconut water-based diluent (ACP-101c) associated with extra virgin coconut oil (CO) as an external cryoprotectant in the conservation of cryopreserved buck sperm. For cryopreservation, the ejaculates from four bucks were pooled and divided into three aliquots and diluted at 37°C for treatments T1 (ACP-101c + 2.5% egg yolk +7% glycerol), T2 (ACP-101c + 2.5% CO +7% glycerol), and T3 (ACP-101c + 5% CO +7% glycerol). Then, the samples were packaged and cooled at a rate of 1.07°C/min decrease. Upon reaching 4°C, the samples were stored in a refrigerator at 4°C for 30 minutes for stabilization. After this period, the straws were frozen in nitrogen vapor for 15 minutes and then immersed and stored in liquid nitrogen at -196°C. After thawing, the samples were evaluated for sperm kinetics, plasma membrane integrity, acrosomal integrity, membrane functionality, mitochondrial activity (MA), and sperm morphology. In this study, no statistically significant differences were observed between the three treatments regarding the kinetic parameters (p > 0.05; Table 1). However, in relation to the velocities, a reduction was observed beyond the expected. There were no statistically significant differences between the diluents T1, T2, and T3 for the three velocities (curvilinear velocity [VCL], linear velocity [VSL], average path velocity [VAP]). Furthermore, no statistically significant differences were observed (p > 0.05) among treatments regarding the evaluation of membrane integrity, the functional membrane, MA, and sperm morphology after thawing. In conclusion, the use of CO in concentrations of 2.5% and 5.0% is effective in maintaining goat sperm quality, presenting itself as an alternative diluent for international programs of artificial insemination and embryo transfers. [Table: see text].

Sêmen ovino e caprino imunossexado e diluído em meio de conservação à base de água de coco em pó (ACP101/102c) / Ram and goat semen immunosexed and diluted in powdered coconut water-based preservation medium (ACP101/102c)

Sperm sexing aims to separate sperm populations in carriers of the "X" or "Y" chromosome. Currently, flow cytometry is a technique that allows greater accuracy; however, it causes structural changes in sperm, reduces viability, and has a high cost. As a result, other methods have been researched, including immunosexing, which uses monoclonal antibodies to detect sex-specific surface antigens. Thus, the objective of this study was to evaluate the immunosexing technique using a monoclonal antibody against sex-specific protein (HY) in the conservation of ram and goat semen in ACP101/102c. Ejaculates from five rams and five goats were collected with the aid of an artificial vagina; they were evaluated and submitted to the immunosexing protocol, according to the manufacturer's recommendations, using the Monoclonal Antibody Kit specific for mammalian sperm with "Y" chromosomes (HY; HY Biotechnology, Rio de Janeiro, RJ, Brazil). After sexing, the supernatant was resuspended in the cryopreservation diluent: ACP ram (ACP101/102c + 20% egg yolk + 7% glycerol) and ACP goat (ACP101/102c + 2.5% egg yolk + 7% glycerol), packaged in 0.25 mL straws, refrigerated at 4°C, stabilized for 30 min, frozen in liquid nitrogen vapor (-60°C) for 15 min, immersed in liquid nitrogen, and stored in cryogenic cylinders. The samples were evaluated in natura (T1), after immunosexing (T2) and after thawing (T3) for sperm motility subjectively using conventional microscopy (40x). Plasma membrane integrity (IMP) and sperm cell morphology were evaluated by the smear staining technique using eosin-nigrosine dye, and the percentages of healthy and morphologically defect spermatozoa were determined. In the evaluation of ram semen regarding sperm motility and IMP, no statistically significant differences were observed between treatments after sexing in the evaluation of absolute data (P > 0.05), with the difference being observed only between T1 and T2, and T3 (P < 0.05). Regarding the relative percentage and sperm morphology, no statistically significant differences were observed (P > 0.05). Regarding the evaluation of goat semen samples, the motility parameters were consistent with the technique submitted; however, the IMP data did not appear as expected, requiring further evaluation for a better assessment of the technique for this species. The data obtained from ram semen submitted to the immunosexing protocol, regarding the absolute evaluation of motility and IMP, demonstrated that the non-sexed semen (T1) was superior to the sexed treatments (T2 and T3); however, it is noteworthy that freezing started with approximately 50% of the cells, since the immunosexing technique results in a loss of viability of approximately 50% of the sperm, which corresponds to the ratio of sperm carrying the X chromosome. In addition, when the data in this study were transformed into relative values, no statistical differences were observed, indicating that the immunosexing protocol, as well as the freezing protocol, did not significantly affect the quality of ram sperm cells. In relation to the immunosexing of goat semen, future studies should be conducted in vitro to define a more appropriate protocol for the species and, in addition, in vivo studies should be performed to prove the quality of the technique. It was concluded that the immunosexing process using a monoclonal antibody against sex-specific protein (HY) associated with the use of powdered coconut water diluent (ACP101/102c) in the cryopreservation of semen proved to be efficient in the in vitro evaluation of ovine species.(AU)