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This study assessed the outcomes of nonsurgical embryo recovery (NSER) after superovulation (SOV) in five locally adapted Brazilian breeds of sheep and goats. The objective was to evaluate the feasibility and efficiency of using SOV combined with a less-invasive embryo collection technique for supplying the Brazilian animal gene bank with germplasm from specific genotypes of interest. Morada Nova (n = 20), Santa Inês (n = 20), and Somalis (n = 20) ewes received an intravaginal progesterone (330 mg) device for 9 days, while Canindé (n = 15) and Moxotó (n = 15) goats received an intravaginal medroxyprogesterone acetate (60 mg) device for 6 days. All females received 133 mg of porcine follicle-stimulating hormone (pFSH) administrated in six decreasing doses 12 hours apart, starting 60 hours before device removal, plus 37.5 µg of d-cloprostenol at the fifth and sixth pFSH dose. Donors in estrus were mated with fertile males. The corpora lutea (CL) number was assessed by ultrasonography 1 day before NSER. On day 6.5 or 7 after estrus, NSER was performed following hormonally induced cervical relaxation. A total of 97% of sheep and 90% of goats responded with estrus, and among those, 91% of sheep and 85% of goats presented a CL. In ewes, the numbers of CL were greater (p < 0.05) in the Santa Inês breed, while similar (p > 0.05) CL numbers were found among the goat breeds. All viable embryos were freezable (excellent and good quality) and the number per donor was 7.8 for sheep and 4.9 for goats. All parameters of NSER efficiency, embryo yield, and fertility post-NSER did not differ (p > 0.05) between breeds among each species. The SOV-NSER procedures applied for an embryo biobank supply of locally adapted Brazilian breeds of small ruminants were efficient regarding production of cryopreservable embryos, and preservation of donor fertility. Therefore, SOV followed by NSER is recommended for embryo biobank assembly in sheep and goats.

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By allowing for the creation of embryo banks, reproductive biotechnologies play an essential role in the preservation of endangered goat breeds' genetic diversity. This study focused on comparing both available embryo collection methods [laparotomy (LAP) vs. nonsurgical embryo recovery (NSER)] in Canindé goats to create an embryo bank for later use in a breed conservation program. Twelve females were superovulated and subjected to either the LAP or NSER technique for embryo recovery. The recovery rate was similar (p > 0.05) between NSER (86.8% ± 5.6%) and LAP (92.8% ± 4.0%). Moreover, there were no differences (p > 0.05) in the number of structures recovered, the viable embryos, and the freezable embryos per goat, respectively, for NSER (11.7 ± 1.3, 11.2 ± 1.5, and 10.2 ± 1.1) and LAP (10.3 ± 1.0, 8.7 ± 0.7, and 8.0 ± 0.8). Overall, 132 structures were collected out of 151 ovulations (∼12.6 ± 1.2 corpora lutea per goat). Finally, the procedure duration time was also similar (p > 0.05) for NSER versus LAP, respectively: 32.3 ± 3.3 versus 30.8 ± 3.9 minutes. In conclusion, the NSER method results proved to be similar to the LAP technique in small-sized Canindé goats. It was noticeable, however, that the NSER technique is simpler and provides the possibility for successive procedures with few health risks and sequels for females. This study may hopefully boost in vivo embryo production programs in the Canindé breed, facilitating the formation of embryo banks and so assuring the availability of genetic diversity before any decline becomes irreversible.

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BACKGROUND: Reproductive efficiency after hydrometra (HD) treatment is usually unsatisfactory. METHODS: To identify mechanisms involved in low reproductive efficiency of HD-treated goats, pluriparous dairy goats treated for HD (n=10, HD) or with no reproductive disorders (n=11, control: CONT) were induced to oestrus and superovulated. Goats were mated with fertile bucks and seven days after oestrus, non-surgical embryo recovery was performed. Embryos were evaluated and gene expression was performed. RESULTS: There were no differences (P>0.05) in sexual behaviour parameters, superovulation response, mean number of retrieved structures and viable embryos between groups; although embryo recovery rate was higher (P=0.01) in CONT group. Structures in delayed stage (8-16 cells) were more frequent (P<0.05) in HD (29 vs 1 per cent) goats, as well as the percentage of advanced embryos was greater (P<0.05) for CONT (59.3 vs 33.3 per cent) goats. However, the expression of genes related to apoptosis (BAX and Bcl-2), trophectoderm differentiation (CDX2) and pluripotency maintenance (NANOG) was not affected (P>0.05) in embryos that reached the morulae and blastocyst stages. CONCLUSION: Although the HD embryos that developed to morula and blastocyst stages showed no change in the expression of genes related to their quality and implantation capacity, overall, embryo development was impaired in HD-treated goats.

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The aim of this work was to determine whether a cervical dilation protocol (CDP) composed of only oxytocin can be used to perform transcervical (non-surgical) embryo transfer in sheep (NSET) without affecting the viability of the corpus luteum (CL). Likewise, we evaluated whether a cervical transposing test with a Hegar dilator (CT Hegar test), performed at oestrous time, could be used to screen ewes for NSET (greater or lower chances to transpose the cervix). For that, oestrous and ovulation synchronization was performed in 25 Santa Inês ewes to induce the dioestrous condition. Animals went through the following CDP in a crossover design: E + OX, oestradiol benzoate (100 µg intravenously [IV]) and oxytocin (100 IU IV); OX, oxytocin (100 IU IV); and SAL, saline solution (IV). Using a Hegar dilator, cervical transposing attempts were performed at oestrous (D0) and dioestrous time (D8). The viability of the CL (morphology, luteal blood flow and progesterone values) was evaluated by ultrasonography (colour Doppler and B-mode) and by serum progesterone measurement from D7 to D13. The cervical transposing rate was lower for the SAL group (64%; 16/25; p < .05) and did not differ between the E + OX (88%; 22/25, p > .05) and OX (84%; 21/25, p > .05) groups. No treatment affected the CL viability. The CT Hegar test showed a high sensitivity (85.7%-93.3%), satisfactory accuracy (72%-84%), low false-negative rate (6.7%-14.6%), but high false-positive rate (46%-66.7%). In conclusion, a CDP protocol composed exclusively of oxytocin can lead to good cervical transposing rates and does not affect the viability of the CL. In addition, a screening test (CT Hegar) performed at oestrus can identify ewes for which cervical transposing will likely not occur at NSET.

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This study aimed to verify the reproductive seasonality in Saanen goats from distinct parity orders (nulliparous, primiparous, and pluriparous) throughout an entire year in the Southeast Region of Brazil. In addition, it was also verified the influence of environmental indexes, metabolic profile, body weight, and social interactions on the reproductive seasonality of these animals. Forty Saanen goats kept under intensive system at latitude 22° 52' 30″ s and tropical photoperiod (11-13 h of light per day) were used. Every 15 days, blood from 24 animals (8 animals per group) was collected for assessment of serum progesterone levels. Monthly, environmental data (rainfall index, maximum and minimum temperature, and time of natural daylight) and blood were collected to evaluate the metabolic profile. Weighting and body condition score measurement were also carried out every 2 months. There was no difference in body weight and body condition score in primiparous and pluriparous goats. Nulliparous goats showed natural breeding season in the winter season while the primiparous and pluriparous goats remained cyclical in autumn and winter season. Regardless of the parity order, all goats showed a seasonal anestrus in the spring season. From December, social interactions were able to reestablish, in distinct degrees, the cyclical state in the goats. Likewise, environmental and weight indexes had low and moderate influence, respectively, on the reproductive seasonality in the Saanen goats kept under tropical conditions.

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The present study evaluated the effect of four ovarian stimulation protocols on the follicular population and molecular status of cumulus-oocyte complexes (COCs). Twelve Santa Inês ewes (in a cross-over design) received 80 or 120mg FSH alone in a multiple-dose (MD80 and MD120) regimen or in combination with 300IU equine chorionic gonadotrophin (eCG) in a one-shot (OS80 and OS120) protocol. The follicular population, COC recovery rate, mean COCs per ewe and the rate of brilliant Cresyl blue-positive (BCB+) COCs were similar among treatments (P>0.05). The expression of markers of oocyte competence (ZAR1, zygote arrest 1; MATER, maternal antigen that embryo requires; GDF9, growth differentiation factor 9; BMP15, bone morphogenetic protein 15; Bcl-2, B-cell lymphoma 2; BAX, Bcl-2 associated X protein) and the steroidogenic pathway (ERα, oestrogen receptor α; LHr, LH receptor; FSHr, FSH receptor; STAR, steroidogenic acute regulatory protein) was affected by stimulation. Specifically, the expression of markers of the steroidogenic pathway was reduced with increasing FSH dose in the OS protocol. FSH at a dose of 80mg reduced the expression of FSHr and ERα in the OS versus MD protocol. Conversely, in MD protocol, only LHr was affected by increasing FSH dose. In conclusion, 80mg FSH in the MD or OS protocol was sufficient to promote the development of multiple follicles and obtain fully grown (BCB+) oocytes. The MD protocol may be more appropriate for the production of better-quality oocytes.

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Brazil has presented tremendous progress in non-surgical embryo transfer (NSET) in sheep and goats. New instruments and techniques for non-surgical embryo recovery (NSER) and NSET in small ruminants were implemented. Recent improvements include refinement of the protocols for cervical relaxation combining oestradiol-oxytocin-cloprostenol treatment at specific times before NSER in sheep; recipient goats do not require any hormonal drugs to induce cervical dilation and direct embryo transfer by the cervical route yields excellent results. Transrectal ovarian ultrasonography (B-mode but especially colour Doppler) have proven to be accurate methods to localise and enumerate corpora lutea and luteinised unovulated follicles in recipient and donor does and ewes. An array of new criteria for selecting superior animals for NSER and NSET (e.g. cervical mapping) have been developed by Brazilian researchers. Extensive studies on both technologies were initially conducted in commercial breeds of goats and sheep but have been gradually extended to some native breeds of sheep (germplasm conservation) and dairy goat operations. It is speculated that, in future, NSER and NSET may become methods of choice for caprine and ovine embryo recovery and transfer in Brazil, and then globally. Due primarily to the efficiency of NSET in goats, a novel interspecies (e.g. bovine) IVP method may soon be developed on a large scale. The Brazilian experience is an invaluable source of information and know-how promoting the replacement of conventional surgical assisted reproductive technologies with non-surgical procedures and hence supporting the rapid development of the embryo transfer industry in small ruminants.

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The primary goal of this study was to employ ultrasonography to examine the ovaries of ewes undergoing superovulatory treatment for correlations between antral follicular blood flow and ovarian responses/embryo yields. Five Santa Inês ewes were subjected to a short- (Days 0-6, Group 1) and five to a long-term progesterone-based protocol (Days 0-12, Group 2) to synchronize estrus and ovulations after the superovulatory treatment. Porcine FSH (pFSH, 200mg) was administered in 8 decreasing doses over 4 days, starting on Days 4 and 10 in Groups 1 and 2, respectively. After CIDR removal, all ewes were bred by a ram and embryos were recovered surgically 7 days later. Transrectal ovarian ultrasonography was performed the day before and on all 4 days of the superovulatory treatment. Both an arbitrary-scale [(0) non-detectable; (1) small; (2) moderate; (3) intense blood flow] and quantitative analysis of the blood flow area were used to assess the follicular blood flow in color Doppler images. There were no significant correlations between the arbitrary blood flow scores and superovulatory responses in the ewes of the present study. However, there was a positive correlation between the quantitative estimates of follicular blood flow on the final day of the superovulatory treatment, and the number (DA: r=0.68, P<0.05; DA/TA×100%: r=0.85, P<0.05) and percentage (DA: r=0.65, P<0.05; DA/TA×100%: r=0.91, P<0.001) of unfertilized eggs (DA: Doppler area, TA: total area of the largest ovarian cross section). This experiment presents a commercially practical tool for predicting superovulatory outcomes in ewes and evidence for the existence of follicular blood flow threshold that may impinge negatively on oocyte quality when surpassed during hormonal ovarian superstimulation.

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