The main goal of this investigation is to show how to create and repair different types of median nerve (MN) lesions in the rat. Moreover, different methods of simulating postoperative physiotherapy are presented. Multiple standardized strategies are used to assess motor and sensory recovery using an MN model of peripheral nerve lesion and repair, thus permitting easy comparison of the results. Several options are included for providing a postoperative physiotherapy-like environment to rats that have undergone MN injuries. Finally, the paper provides a method to evaluate the recovery of the MN using several noninvasive tests (i.e., grasping test, pin prick test, ladder rung walking test, rope climbing test, and walking track analysis), and physiological measurements (infrared thermography, electroneuromyography, flexion strength evaluation, and flexor carpi radialis muscle weight determination). Hence, this model seems particularly appropriate to replicate a clinical scenario, facilitating extrapolation of results to the human species. Although the sciatic nerve is the most studied nerve in peripheral nerve research, analysis of the rat MN presents various advantages. For example, there is a reduced incidence of joint contractures and automutilation of the affected limb in MN lesion studies. Furthermore, the MN is not covered by muscle masses, making its dissection easier than that of the sciatic nerve. In addition, MN recovery is observed sooner, because the MN is shorter than the sciatic nerve. Also, the MN has a parallel path to the ulnar nerve in the arm. Hence, the ulnar nerve can be easily used as the nerve graft for repairing MN injuries. Finally, the MN in rats is located in the forelimb, akin to the human upper limb; in humans, the upper limb is the site of most peripheral nerve lesions. Video Link The video component of this article can be found at https://www.jove.com/video/59767/ Introduction Peripheral nerve lesions occur regularly as a result of trauma, infection, vasculitis, autoimmunity, malignancy, and/or radiotherapy 1,2. Unfortunately, peripheral nerve repair continues to present clinically unpredictable and frequently disappointing results 3,4. There is widespread consensus that considerable basic and translational research is still needed to improve the prospect of those affected 4,5,6,7. The rat MN shows great similarities to that of humans 8,9 (Figure 1). Originating from the brachial plexus in the axillary region, this nerve descends into the medial aspect of the arm, reaching the elbow, and branching off to the majority of the muscles in the ventral compartment of the forearm. The MN reaches the hand, where it innervates the thenar muscles and the first two lumbrical muscles as well as to part of the rat's hand skin 9 (Figure 1). Using the rat MN, it is possible to adequately replicate peripheral nerve lesions in humans 10,11,12. This nerve has several potential research advantages relative to the customarily used sciatic nerve. Because the MN is located in the forelimb of rats (akin to t...

Summary: This study was aimed to test low doses of a GnRH agonist, deslorelin acetate (DA), for induction of multiple ovulations in mares and to determine its impact upon their reproductive efficiency. Seven mares aging from 8 -20 years were used in three consecutive reproductive cycles. Mares were initially monitored by ultrasound irrespectively of cycle stage, inseminated and submitted to embryo collection (EC) (T1). Immediately after, mares received 7.5 mg dinoprost tromothamine (DT) and were monitored by ultrasound twice a day until larger follicle reached 23 -25 mm and the second >18 mm (T2). At this time point, mares received 100 µg DA and ovulation was induced with 1000 µg DA and 1000 IU hCG when largest follicle reached 33 -35 mm in diameter, followed by EC. Mares were further allocated to T3 when received 7.5 mg DT after EC on T2 and 100 µg DA 48 h later. DA treatment was performed until dominant follicle reached 34 ±1 mm or 6 days of application. All EC were performed 8 days after ovulation. Mares with multiple ovulations in T1, T2 and T3 were 14.28 % (1/7), 100.00 % (7/7) and 0.00 % (0/7), respectively, and averaged 0.43 ± 0.53 in T1, 0.86 ± 0.38 in T2 and 0.00 in T3 embryos per donor, respectively. Embryo recovery rate was 43.00 % in T1, 85.71 % in T2 and 0.00 % T3. In conclusion, use of DA in mares with follicles larger than 25mm enhanced dominant and co-dominant follicle growth, that ultimately increased the incidence of multiple ovulations and embryo recovery rate.

This study aimed to evaluate the effect of temporary suckling interruption associated with the male effect on reproductive performance of pluriparous Santa Inês ewes. The females were kept apart from the males for 60 days and then randomly distributed into three treatments associated with the male effect (DT0, DT24 and DT48); in DT0, there was no suckling interruption; in DT24, suckling was interrupted for 24 hours, and in DT48, sucking was interrupted for 48 hours. Estrous distribution was observed within 31 (DT0), 27 (DT24) and 38 (DT48) days of the breeding season. Estrous synchronization up to the 5th day of the mating season was observed in 15% (DT0), 30% (DT24) and 25% (DT48) of the females, with no difference among treatments. Estrous percentages were 90% (DT0), 100% (DT24) and 100% (DT48), with no difference among treatments. Pregnancy rates were 38.4% (DT0), 60.0% (DT24) and 45.0% (DT48) with no difference among treatments. Prolificacy was 1.43 (DT0), 1.17 (DT24) and 1.22 (DT48) and did not differ between treatments. In conclusion, temporary suckling interruption associated with the male effect is efficient to induce estrous but not to synchronize estrous or increase the pregnancy rates and prolificacy of Santa Inês ewes during a 45-day breeding season.Keywords: anestrous, biostimulation, reproduction, sheep. EFEITO MACHO ASSOCIADO AO DESMAME TEMPORÁRIO NO DESEMPENHO REPRODUTIVO DE OVELHAS SANTA INÊSRESUMO: O estudo teve como objetivo avaliar o efeito do desmame temporário associado ao efeito macho sobre o desempenho reprodutivo de ovinos Santa Inês. As fêmeas foram mantidas distantes dos machos por 60 dias e aleatoriamente distribuídas em três tratamentos associados ao efeito macho (DT0, DT24 e DT48), no qual em DT0, não houve interrupção da amamentação; em DT24, amamentação interrompida por 24 horas e em DT48, interrupção da amamentação por 48 horas. Distribuição de estro foi observada em 31 (DT0), 27 (DT24) e 38 (DT48) dias da estação de monta. Sincronização de estro até o quinto dia da estação de monta foi observada em 15% (DT0), 30% (DT24) e 25% (DT48) das fêmeas, não havendo diferença entre os tratamentos. Percentagens de estro foram de 90% (DT0), 100% (DT24) e 100% (DT48), não havendo diferença entre os tratamentos. As taxas de prenhez foram de 38,4% (DT0), 60,0% (DT24) e 45,0% (DT48), sem diferença entre os tratamentos. A prolificidade foi de 1,43 (DT0), 1,17 (DT24) e 1,22 (DT48), e não diferiu entre os tratamentos. Em conclusão, o desmame temporário associado ao efeito macho é eficiente na indução do estro, embora não seja eficiente na sincronização de estros e não aumente as taxas de gestação e prolificidade das ovelhas Santa Inês durante uma estação de monta de 45 dias.Palavras-chave: anestro, bioestimulação, ovinos, reprodução.

The addition of growth factors and vitamins enhances goat embryonic development in vitro. However, few attempts have been reported trying to identify supplementation regimens for oocyte maturation or embryo culture with additive properties. The present report was aimed to evaluate if retinoids [0.3 μM retinyl acetate (RAc) and 0.5 μM 9-cis-retinoic acid (RA)] supplementation during goat oocyte maturation and retinoids and/or 50 ng mL-1 IGF-I during embryo culture synergically enhanced embryonic development while diminishing the incidence of apoptosis. All combinations of RAc and RA treatment produced blastocysts with similar efficiencies, while IGF-I enhanced embryos yields irrespectively of retinoid addition. Moreover, retinoids and IGF-I supplementation showed similar caspase activity or DNA fragmentation indexes in blastocysts. In conclusion, supplementation with retinoids and IGF-I during goat embryo culture enhances blastocysts development without synergic reduction of apoptosis.

The study was aimed to test the effect of the separation distance between males and females during the preconditioning period on the reproductive performance of Santa Inês ewes after the male effect. Santa Inês ewes were kept at distances of 3000 m (T1), 3 m (T2), and 300 m (T3) from rams for 60 days before starting 45-day mating seasons during the dry period (DP) and rainy periods (RP). Mating events were observed daily at 6:00 h and 16:00 h by trained personnel for one hour intervals. Estrous were scored as synchronized when observed until day 5 after breeding season start. Pregnancy diagnosis was performed by ultrasonography. In the DP, the first estrous averaged at 15.45±10.36 (T1), 9.25±6.41 (T2) and 13.05±10.24 (T3) days and in RP was 8.73±5.84 (T1), 9.30±5.62 (T2) and 6.10±5.66 (T3) days. All females cycled during both DP and RP. Estrous synchronization occurred in 20% of the females during DP (T1: 30%, T2: 15%, and T3: 15%). In the RP, estrous synchronization occurred in 40% of all females (T1: 30%, T2: 35%, and T3: 45%). The pregnancy rates in DP and RP were T1: 85%, T2: 80%, and T3: 75%. The results show that the male effect can be obtained simply by avoiding physical contact between males and females throughout the year under tropical conditions.

Free tissue transfer has been increasingly used in clinical practice since the 1970s, allowing reconstruction of complex and otherwise untreatable defects resulting from tumor extirpation, trauma, infections, malformations or burns. Free flaps are particularly useful for reconstructing highly complex anatomical regions, like those of the head and neck, the hand, the foot and the perineum. Moreover, basic and translational research in the area of free tissue transfer is of great clinical potential. Notwithstanding, surgical trainees and researchers are frequently deterred from using microsurgical models of tissue transfer, due to lack of information regarding the technical aspects involved in the operative procedures. The aim of this paper is to present the steps required to transfer a fasciocutaneous epigastric free flap to the neck in the rat.This flap is based on the superficial epigastric artery and vein, which originates from and drain into the femoral artery and vein, respectively. On average the caliber of the superficial epigastric vein is 0.6 to 0.8 mm, contrasting with the 0.3 to 0.5 mm of the superficial epigastric artery. Histologically, the flap is a composite block of tissues, containing skin (epidermis and dermis), a layer of fat tissue (panniculus adiposus), a layer of striated muscle (panniculus carnosus), and a layer of loose areolar tissue.Succinctly, the epigastric flap is raised on its pedicle vessels that are then anastomosed to the external jugular vein and to the carotid artery on the ventral surface of the rat's neck. According to our experience, this model guarantees the complete survival of approximately 70 to 80% of epigastric flaps transferred to the neck region. The flap can be evaluated whenever needed by visual inspection. Hence, the authors believe this is a good experimental model for microsurgical research and training.

SummaryPluripotency-associated transcription factors (PATFs) modulate gene expression during early mammalian embryogenesis. Despite a strong understanding of PATFs during mouse embryogenesis, limited progress has been made in ruminants. This work aimed to describe the temporal expression of eight PATFs during both sheep and cattle preimplantation development. Transcript availability of PATFs was evaluated by reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) in eggs, cleavage-stage embryos, morulae, and blastocysts. Transcripts of five genes were detected in all developmental stages of both species (KLF5, OCT4, RONIN, ZFP281, and ZFX). Furthermore, CMYC was detected in all cattle samples but was found from cleavage-stage onwards in sheep. In contrast, NR0B1 was detected in all sheep samples but was not detected in cattle morulae. GLIS1 displayed the most significant variation in temporal expression between species, as this PATF was only detected in cattle eggs and sheep cleavage-stage embryos and blastocysts. In silico analysis suggested that cattle and sheep PATFs share similar size, isometric point and molecular weight. A phenetic analysis showed two patterns of PATF clustering between cattle and sheep, among several mammalian species. In conclusion, the temporal expression of pluripotency-associated transcription factors differs between sheep and cattle, suggesting species-specific regulation during preimplantation development.

Exposure of caprine oocytes and embryos to retinoids enhances embryonic development, but the mechanisms governing this phenomenon have not been characterised. The aim of the present study was to evaluate if the incidence of apoptosis is affected by the addition of retinyl acetate (RAc) and 9-cis-retinoic acid (RA) during in vitro maturation (IVM) of caprine oocytes. Embryonic development was recorded on days 3 and 8 post-fertilisation, and apoptosis was measured by caspase activity and DNA fragmentation (TUNEL assay). Control zygotes had lower capacity to cleave and reach the blastocyst stage (24.45 ± 2.32 and 5.32 ± 0.81, respectively) than those of RAc-(29.96 ± 1.62 and 7.94 ± 0.93, respectively) and RA-treated groups (30.12 ± 1.51 and 7.36 ± 1.02, respectively). Oocytes and blastocysts positive for TUNEL assay were more frequent, respectively, in the controls (8.20 ± 0.78, 8.70 ± 1.05) than in RAc (5.60 ± 0.52, 4.80 ± 0.51) and RA (6.40 ± 0.69, 5.40 ± 0.69). Caspase activity did not differ between control oocytes (7.20 ± 0.91), RAc (6.60 ± 0.68) and RA (7.30 ± 0.67), but it was reduced in RAc-(5.05 ± 0.62) and RA-treated blastocysts (5.75 ± 0.22) compared to controls (8.35 ± 0.71). These results indicate that the addition of retinoids during IVM increases the developmental potential of goat embryos with a concomitant reduction in apoptosis rates.