J. M. G. Souza-Fabjan

Reproductive parameters of dairy goats after receiving two doses of d-cloprostenol at different intervals

This study evaluated the efficiency of two d-cloprostenol injections at different intervals on the reproductive parameters of dairy goats. Trial 1 comprised 54 goats allocated to receive two 37.5μg d-cloprostenol doses at intervals of seven (T7, n=19), 10 (T10, n=18), and 11.5 (T11.5, n=17) days. Trial 2 comprised 62 goats allocated to receive injections at T7 (n=30) and T11.5 (n=32). Ultrasonography was done and blood was collected just before d-cloprostenol injections. After the second dose, goats were artificially inseminated (AI) with frozen-thawed semen at 18-24h (Trial 1) or at 10-24h (adjusted according to the time of estrus onset in Trial 2) after estrus detection. Estrus response rate did not differ (P>0.05) among groups in Trials 1 (T7=94.7%; T10=88.9%; T11.5=88.2%) and 2 (T7=90.0%; T11.5=96.9). All females showed progesterone concentrations >1ng/mL before both d-cloprostenol injections. The largest follicle diameter present on ovaries was similar (P>0.05) among treatments at the first and second dose. The second largest follicle diameter was superior (P<0.05) to T7 than to T10 and T11.5 goats at first dose only. This possibly resulted in lower interval to estrus (P<0.05) in T7-treated goats than other treated goats in both trials. The conception rate was similar among treatment groups in Trials 1 (T7=55.6%; T10=18.8%; T11.5=26.7%) and 2 (T7=85.2%; T11.5=93.6%). The three treatments efficiently synchronized estrus. T7 and T11.5 protocols resulted in high estrus synchrony and conception rates when adjusting the AI time according to interval of estrus.

Reproductive features and use of an anti-inflammatory drug in estrus-induced dairy goats artificially inseminated in a standing position with cervix immobilization

This study evaluated reproductive features and role of Flunixin-Meglumine at timed artificial insemination (AI), using a new technique of standing position with cervix immobilization. In Experiment 1, 10 goats (n=5 nulliparous [Null] and 5 pluriparous [Plu]) were evaluated after estrus induction by recorded reproductive parameters to define the ideal time for AI. In Experiment 2, goats were artificially inseminated 51-54h after sponge removal with frozen-thawed semen. At AI, 1mL saline (CONTROL; 18 Null and 14 Plu) or 50mg Flunixin-Meglumine (FLUNIXIN; 15 Null and 18 Plu) was administered i.m. Location of semen deposition was recorded for both groups. In Experiment 1, all sexual behavior and ovulatory parameters were similar between Null and Plu for estrus response and ovulation (100%), interval from sponge removal to ovulation (∼64.2h), largest ovulatory follicle diameter (∼6.6mm), and number of ovulations (∼2.0). In Experiment 2, pregnancy rate was superior (P<0.01) for CONTROL (62.5%; 10 Null and 10 Plu) than FLUNIXIN (30.3%; 3 Null and 7 Plu) goats. Regardless of the treatment, intrauterine AI was more frequent (P<0.01) in Plu (100.0%; 32/32) than in Null (69.7%; 23/33) goats. Moreover, AI was more time-consuming (P<0.01) in Null (44±37s; 4-139s) than in Plu (21±19s, 4-78s) goats. Therefore, administration of Flunixin-Meglumine at the time of AI adversely affected pregnancy rate. High rates of intrauterine cervical penetration were obtained, achieving good pregnancy rates in goats not receiving Flunixin-Meglumine.

Comparison of different sperm selection techniques in ram frozen-thawed sperm.

Background: The success of fertilization is directly associated with semen quality and the sperm preparation. Considering the common use of cryopreserved spermatozoa, there is a need to develop strategies for sperm preparation in order to achieve a sperm sample of high quality through a rigorous selection of sperm. Thus, sperm cells are being more extensively investigate. This study aimed evaluating the influence of different sperm selection techniques on ram sperm parameters in semen preparation. Materials, Methods & Results: Frozen-thawed commercial semen from 10 Santa Ines rams was subjected to either: swim-up, Percoll, mini-Percoll, sperm washing by centrifugation or a control group. After each technique, samples were incubated at 37°C for 1 h, 2 h and 3 h. At post-selection moment (0 h) and at each interval, sperm recovery rate, motility, capacitation and plasma membrane (PM) integrity were analyzed. The lowest (P 0.05). Most part of motility parameters were not affected (P > 0.05) by the technique at 0 h; just swim-up obtained higher (P 0.05), regardless of interval incubation. However, the latter three techniques presented more (P 0.05). Discussion: The present study evaluated the sperm cell and its preparation for receiving the oocyte under optimal conditions. evaluate the sperm cell and its preparation for receiving the oocyte under optimal conditions. Although the swim-up technique promoted higher rates for some of the sperm parameters evaluated, Percoll protocols are the most widely used procedures for selection during the sperm preparation in many species, possibly because of its greater speed, practical method and convenience compared to the swim-up technique. Percoll and mini-Percoll recovered approximately 10 times more cells than swim-up, which is an important feature to be considered during sperm preparation for in vitro fertilization (IVF), being possible to use only one semen straw. The high capacitated and acrosome reaction rates observed after the treatments in the current study, are probably reinforced by changes in sperm cells caused by the cryopreservation process. In order to strength the evidence that frozen-thawed sperm, even after selection, is sensible and reactive to capacitation-like events, we demonstrated the capacitated and acrosome-reacted cell values immediately after the selection treatments behaved differently than when authors used ram fresh sperm. Possibly, this capacitation-like changes observed in frozen-thawed sperm occurs regardless of the selection treatment used. Analyzing the motility parameters immediately after the selection, all treatments maintained or increased the rates compared to the control group. The swim-up, mini-Percoll and Percoll did not differ in any parameters. Given that Percoll and mini-Percoll did not show differences in relation to swim-up for motility parameters, such techniques can be used to replace the latter, obtaining similar sperm samples with good quality. However, swim-up technique involves a procedure that recovers a clean fraction without debris and other types of cells, with high rate of mobile sperm with excellent quality, reason why it can justify the higher recovery of intact spermatozoa after the technique.