Three superovulation protocols for in vivo embryo production in Santa Inês sheep / Três protocolos para produção in vivo de embriões em ovelhas Santa Inês

There is still no consensus regarding the best protocol for in vivo embryo production in sheep despite increasing studies in this area. Moreover, there is variability in the response of ewes to superovulation (SOV). An approach to mitigate this inconsistency is to initiate gonadotropin administration under favorable ovarian conditions. The present study compared three treatments in a crossover design: a traditional SOV protocol (TRAD) and "Day 0" D0 SOV protocol with (D0+GnRH), or without Lecilerin (D0-GnRH). Fifteen Santa Inês ewes received 200 mg of FSH at six decreasing doses and PGF2α with the fifth dose of FSH. They were naturally mated with fertile rams and subjected to surgical embryo collection. The number of viable embryos was similar among the different treatments (TRAD = 6.0 ± 4.7; D0-GnRH = 3.8 ± 6.4; D0+GnRH = 7.5 ± 6.5). Regardless of the treatment method, ewes with follicles ≤ 4 mm, at the first FSH dose, produced more viable embryos (9.6 ± 6.0, P < 0.05) compared to ewes that had follicles > 4 mm at the beginning of the SOV (2.9 ± 3.1, viable embryos). Both the TRAD and D0+GnRH groups had fewer animals with large follicles (> 4 mm) at the first FSH dose than the D0-GnRH group (P < 0.05). In conclusion, both the TRAD and D0+GnRH treatments induced a more favorable ovarian condition (follicles ≤ 4 mm) for adequate SOV; although, all three treatments exhibited similar efficacies in Santa Inês sheep.

Ainda não há consenso sobre qual é o protocolo mais apropriado para a produção in vivo de embriões em ovinos, apesar do crescente conhecimento. Uma abordagem para mitigar a variabilidade de resposta de ovelhas à superovulação (SOV) é iniciar a aplicação de gonadotrofinas em uma condição ovariana favorável. O presente estudo comparou três tratamentos em delineamento do tipo crossover: protocolo de SOV tradicional (TRAD) e "Dia 0" D0 SOV sem (D0-GnRH) ou com GnRH (D0+GnRH). Quinze ovelhas Santa Inês foram superovuladas com 200 mg de FSH em seis doses decrescentes e receberam PGF2α na quinta dose de FSH. As ovelhas foram submetidas a monta natural com carneiros férteis e os embriões colhidos por via cirúrgica. O número de embriões viáveis não diferiu entre os tratamentos (TRAD = 6,0 ± 4,7; D0-GnRH = 3,8 ± 6,4; D0+GnRH = 7,5 ± 6,5). Independentemente do tratamento, ovelhas com folículos ≤ 4 mm na primeira dose de FSH produziram mais embriões viáveis (9,6 ± 6,0; P < 0.05) quando comparadas aos animais que apresentavam folículos > 4 mm no início da SOV (2,9 ± 3,1 embriões viáveis). Os grupos TRAD e D0+GnRH apresentaram menor número de animais com folículos grandes (> 4 mm), no momento da primeira dose de FSH, quando comparados ao grupo D0-GnRH (P < 0,05). Em conclusão, os protocolos TRAD e D0+GnRH induziram uma condição ovariana mais favorável (folículos ≤ 4 mm) para a SOV. No entanto, os três tratamentos apresentaram eficiência semelhante em ovelhas Santa Inês.

Relationships of morphological and phototextural attributes of presumptive ovine zygotes and early embryos to their developmental competence in vitro: a preliminary assessment using timelapse imaging

The assessment of morphology and digital image opacity may provide valuable information on the present embryo quality. Time-lapse imaging has been employed in research to establish a means of monitoring the dynamic nature of preimplantation embryo development. The aim of present study was to use time-lapse imaging for assessing various prospective morphometric and phototextural markers of the developmental potential of in vitro-derived ovine embryos. Oocytes were obtained by scarification of ovaries from nine Polish Longwool ewes. After in vitro maturation (IVM) and fertilization (IVF) of oocytes with fresh ram semen, the development of embryos to the blastocyst stage was monitored and evaluated using Primo Vision time-lapse imaging technology. Commercially available Image-Pro® Plus software was used to measure zona pellucida thickness, embryo diameter, total area of the perivitelline space, cellular grey-scale pixel intensity and cellular pixel heterogeneity. Statistical assessment of all attributes was done at various time points during embryo development (i.e., presumptive zygote stage: t(0); first cleavage detected at t(2) or t(3); and second cleavage detected at t(4) or t(6)). Out of thirty-seven zygotes analyzed in this study, five did not divide, 26 arrested before and six developed to the blastocyst stage. Our present results indicate that most parameters analyzed did not differ among embryos varying in their developmental fate except for the perivitelline space area that was greater (P<0.05) for non-dividing zygotes than future blastocysts at the presumptive zygote stage (4040±1850 vs. 857±262 µm2, respectively; means±SEM). Consequently, the measurement of perivitelline space at t(0) can potentially be used to prognosticate developmental potential of in vitro-produced ovine embryos albeit further confirmational studies are needed.(AU)

Effect of different protocols for estrus synchronization on reproductive performance of Santa Inês ewes under Amazon environmental conditions

The objective of this study was to evaluate the effect of different hormonal protocols on the reproductive performance of Santa Inês ewes in Amazon environmental conditions. Twenty-two Santa Inês ewes between 3 and 4 years-old were distributed in a randomized block experimental design, where the treatments consisted of two protocols for estrus synchronization (short and long) with eleven animals each. Data on the occurrence of estrus were described for each protocol. Data of estrus, pregnancy, and prolificity were firstly subjected to ANOVA and a subsequent Tukeys test. Results were considered significant at p 0.05. The short-term protocol presented an interesting successful rate, where above 70% ewes tested had estrus. The long-term protocol also achieved a high successful rate, where above 80% ewes tested had estrus. However, comparing the protocols, the long-term protocol presented better results of positive estrus and pregnancy rates in ewes. Thus, it can be concluded that both protocols presented satisfactory results regarding estrus manifestation, and prolificity (lambs produced per ewe). However, under Amazon environmental conditions, the long-term protocol presented better results regarding positive manifestation of estrus and pregnancy rate.(AU)

Effect of different protocols for estrus synchronization on reproductive performance of Santa Inês ewes under Amazon environmental conditions

The objective of this study was to evaluate the effect of different hormonal protocols on the reproductive performance of Santa Inês ewes in Amazon environmental conditions. Twenty-two Santa Inês ewes between 3 and 4 years-old were distributed in a randomized block experimental design, where the treatments consisted of two protocols for estrus synchronization (short and long) with eleven animals each. Data on the occurrence of estrus were described for each protocol. Data of estrus, pregnancy, and prolificity were firstly subjected to ANOVA and a subsequent Tukeys test. Results were considered significant at p 0.05. The short-term protocol presented an interesting successful rate, where above 70% ewes tested had estrus. The long-term protocol also achieved a high successful rate, where above 80% ewes tested had estrus. However, comparing the protocols, the long-term protocol presented better results of positive estrus and pregnancy rates in ewes. Thus, it can be concluded that both protocols presented satisfactory results regarding estrus manifestation, and prolificity (lambs produced per ewe). However, under Amazon environmental conditions, the long-term protocol presented better results regarding positive manifestation of estrus and pregnancy rate.

Técnica de inseminação artificial por tração cervical e função luteal em ovelhas Santa Inês após estro sincronizado com cloprostenol ou progestágeno-eCG / Technique of artificial ins emination by cervical traction and luteal function in Santa Inês ewes after synchronized estrus with cloprostenol or progestagen-eCG

Avaliou-se a influência do protocolo de sincronização de estro na execução da técnica de inseminação artificial por tração cervical (ITC) e subsequente perfil sérico de progesterona em ovelhas Santa Inês. Um grupo foi submetido a duas aplicações de cloprostenol com sete dias de intervalo (PGF2α, n=43), outro grupo foi sincronizado com MAP-eCG (P4-eCG, n=40) e ovelhas ao estro natural (EN, n=10) formaram grupo controle. Com as ovelhas contidas em estação, foi realizada a técnica ITC utilizando um aplicador metálico e mandril. Foram avaliadas a profundidade de penetração e intensidade de reação da ovelha ao manejo da técnica. Dosagens de estradiol e progesterona foram feitas antes e depois da ITC/estro natural, respectivamente. Os níveis de estradiol foram superiores com P4-eCG vs PGF2α (P < 0,05), mas não houve influência do protocolo na execução da técnica. Ocorreram 83,5% de deposição intrauterina do sêmen, o tempo médio foi de 32 segundos e 90,7% das ovelhas apresentaram reação fraca ou moderada durante o manejo. Os níveis de progesterona foram semelhantes entre ITC e estro natural. Independente do protocolo hormonal, a técnica ITC em ovelhas Santa Inês mantidas em estação mostrou-se viável no tempo de penetração da cérvice e deposição intrauterina do sêmen, não comprometendo a função luteal subsequente.(AU)

The influence of estrus synchronization protocol was evaluated on the artificial insemination technique by cervical traction (ICT) and subsequent progesterone serum profile in Santa Inês ewes. One group was submitted to two applications of cloprostenol seven days apart (PGF2α, n=43), another group was synchronized with MAP-eCG (P4-eCG, n=40) and ewes at natural estrus (NE, n=10) formed a control group. With the ewe contained in the stand position, the ICT technique was performed using a metal applicator and mandrel. Depth of penetration and reaction intensity of the ewe to the handling of the technique were evaluated. Dosages of estradiol and progesterone were performed before and after ICT / natural estrus, respectively. Estradiol levels were higher with P4-eCG vs PGF2α(AU)

Técnica de inseminação artificial por tração cervical e função luteal em ovelhas Santa Inês após estro sincronizado com cloprostenol ou progestágeno-eCG / Technique of artificial ins emination by cervical traction and luteal function in Santa Inês ewes after synchronized estrus with cloprostenol or progestagen-eCG

Avaliou-se a influência do protocolo de sincronização de estro na execução da técnica de inseminação artificial por tração cervical (ITC) e subsequente perfil sérico de progesterona em ovelhas Santa Inês. Um grupo foi submetido a duas aplicações de cloprostenol com sete dias de intervalo (PGF2α, n=43), outro grupo foi sincronizado com MAP-eCG (P4-eCG, n=40) e ovelhas ao estro natural (EN, n=10) formaram grupo controle. Com as ovelhas contidas em estação, foi realizada a técnica ITC utilizando um aplicador metálico e mandril. Foram avaliadas a profundidade de penetração e intensidade de reação da ovelha ao manejo da técnica. Dosagens de estradiol e progesterona foram feitas antes e depois da ITC/estro natural, respectivamente. Os níveis de estradiol foram superiores com P4-eCG vs PGF2α (P < 0,05), mas não houve influência do protocolo na execução da técnica. Ocorreram 83,5% de deposição intrauterina do sêmen, o tempo médio foi de 32 segundos e 90,7% das ovelhas apresentaram reação fraca ou moderada durante o manejo. Os níveis de progesterona foram semelhantes entre ITC e estro natural. Independente do protocolo hormonal, a técnica ITC em ovelhas Santa Inês mantidas em estação mostrou-se viável no tempo de penetração da cérvice e deposição intrauterina do sêmen, não comprometendo a função luteal subsequente.

The influence of estrus synchronization protocol was evaluated on the artificial insemination technique by cervical traction (ICT) and subsequent progesterone serum profile in Santa Inês ewes. One group was submitted to two applications of cloprostenol seven days apart (PGF2α, n=43), another group was synchronized with MAP-eCG (P4-eCG, n=40) and ewes at natural estrus (NE, n=10) formed a control group. With the ewe contained in the stand position, the ICT technique was performed using a metal applicator and mandrel. Depth of penetration and reaction intensity of the ewe to the handling of the technique were evaluated. Dosages of estradiol and progesterone were performed before and after ICT / natural estrus, respectively. Estradiol levels were higher with P4-eCG vs PGF2α

Early pregnancy affects expression of Toll-like receptor signaling members in ovine spleen

Toll-like receptors (TLRs) are involved to the maternal immune tolerance. The spleen is essential for adaptive immune reactions. However, it is unclear that early pregnancy regulates TLR-mediated signalings in the maternal spleen. The purpose of this study was to investigate the effects of early pregnancy on expression of TLR signaling members in the ovine spleen. Ovine spleens were collected at day 16 of the estrous cycle, and at days 13, 16 and 25 of pregnancy (n = 6 for each group). Real-time quantitative PCR, western blot and immunohistochemistry analysis were used to detect TLR signaling members, including TLR2, TLR3, TLR4, TLR5, TLR7, TLR9, myeloid differentiation primary-response protein 88 (MyD88), tumor necrosis factor receptor associated factor 6 (TRAF6) and interleukin-1-receptor-associated kinase 1 (IRAK1). The results showed that expression levels of TLR2, TLR4 and IRAK1 were downregulated, but expression levels of TLR3, TLR5, TLR7, TLR9, TRAF6 and MyD88 were increased during early pregnancy. In addition, MyD88 protein was located in the capsule, trabeculae and splenic cords of the maternal spleen. This paper reports for the first time that early pregnancy has effects on TLR signaling pathways in the ovine spleen, which is beneficial for understanding the maternal immune tolerance during early pregnancy.(AU)

Protected and partially protected fat sources from ruminal degradation for pregnant sheep

Fat sources are important component on animal feed. However, ruminants did not evolve to efficient degrade lipids. Thus, it is necessary to study how its supplementation may affect animal performance. The objective of this study was to evaluate the use of different lipids sources over consumption, performance, metabolites, and feed behavior of pregnant sheep. The experiment was carried out at Capim Branco Experimental Farm, at goat and sheep sector of Federal University of Uberlândia, from August to November 2015. Twenty-four pregnant sheep were used, mean body weight 50 kg and approximate 12 months age. The animals were divided into three treatments (Control, palm oil protected fat and cottonseed). The corn silage was used as the bulk. The roughage: concentrate ratio was 60:40 (on dry matter). Measurements of body weight, body condition score and biometric measurements were taken every 21 days. Ingestive behavior evaluation was performed throughout the experiment. The consumption measurement was made in descriptive way. Shortly after birth, the sheep and their offspring were weighed, the barrel circumference was taken, and samples from the mother's blood were collected. The experimental design was completely randomized with repeated measurements in time. It was verified greater time spent with feeding and chewing in the treatment with cottonseed and consequently less time in idle. There was no statistical difference in weight, barrel circumference (BC) and body condition score (BCS) of the sheep under the different treatments. There was a linear growth in BC measurements and sheep weight over the evaluated periods. There were differences between the treatments for the offspring's average weight. The use of cottonseed as a fat source increases the birth weight of the progeny and improves pregnant sheep metabolic profile in relation to inert fat.

Multiple matings modify the estrous length, the moment of ovulation, and the estradiol and LH patterns in ewes

In several species, mating reduces the estrous length and advances ovulation. The aim of this study was to determine if multiple matings reduces the estrous length and modifies the moment of ovulation, as well as the estradiol and LH patterns in ewes. The estrous cycle of Corriedale ewes was synchronized, and the onset of receptivity was monitored every 3 h with rams, avoiding mating. At the estrous onset, ewes were assigned to two experimental groups (n=10 each): 1) estrous was monitored every 3 h with a ram avoiding mating (group CON), and 2) a ram was allowed to mate and ejaculate once every 3 h (group MAT). The ovaries were scanned with transrectal ultrasonography and blood samples were collected for measuring 17β-estradiol and LH concentrations every 3 h until ovulation. Estrus was shorter in MAT than CON ewes (24.7 ± 1.5 h vs. 30.4 ± 1.5 h, respectively; P=0.02); the proportion of animals that ovulated before the end of estrus was greater in CON ewes: (9/10 vs. 3/10, P=0.009). The area under the LH curve (AUC) was greater in MAT than CON ewes (36.1 ± 3.5 ng.h-1.mL-1 vs 24.9 ± 3.5 ng.h-1.mL-1 P=0.03). However, MAT ewes had a lower 17β-estradiol AUC than CON ewes (41.0 ± 4.9 pg.h-1.mL-1 vs 59.4 ± 4.9 pg.h-1.mL-1 P=0.01). Mating reduced the estrous length, induced a greater secretion of LH but less total 17β-estradiol secreted and, additionally, ovulation occurred more frequently after the end of estrus in mated ewes.(AU)

Protected and partially protected fat sources from ruminal degradation for pregnant sheep

Fat sources are important component on animal feed. However, ruminants did not evolve to efficient degrade lipids. Thus, it is necessary to study how its supplementation may affect animal performance. The objective of this study was to evaluate the use of different lipids sources over consumption, performance, metabolites, and feed behavior of pregnant sheep. The experiment was carried out at Capim Branco Experimental Farm, at goat and sheep sector of Federal University of Uberlândia, from August to November 2015. Twenty-four pregnant sheep were used, mean body weight 50 kg and approximate 12 months age. The animals were divided into three treatments (Control, palm oil protected fat and cottonseed). The corn silage was used as the bulk. The roughage: concentrate ratio was 60:40 (on dry matter). Measurements of body weight, body condition score and biometric measurements were taken every 21 days. Ingestive behavior evaluation was performed throughout the experiment. The consumption measurement was made in descriptive way. Shortly after birth, the sheep and their offspring were weighed, the barrel circumference was taken, and samples from the mother's blood were collected. The experimental design was completely randomized with repeated measurements in time. It was verified greater time spent with feeding and chewing in the treatment with cottonseed and consequently less time in idle. There was no statistical difference in weight, barrel circumference (BC) and body condition score (BCS) of the sheep under the different treatments. There was a linear growth in BC measurements and sheep weight over the evaluated periods. There were differences between the treatments for the offspring's average weight. The use of cottonseed as a fat source increases the birth weight of the progeny and improves pregnant sheep metabolic profile in relation to inert fat.(AU)

Effect of pre-pubertal growth rate of Sohagi ram lambs on some physiological parameters and sexual behavioral patterns at puberty

Thirty healthy Sohagi ram lambs with an average age of 188.6±7.3 days were used to study the effect of pre-pubertal growth rate on some physiological parameters and sexual behavioral patterns at puberty. Ram lambs were divided into three groups (10 animals per each group) according to the previous growth rate until 6 months of age. Groups were marked as fast, medium and slow growing. Animal groups were housed in closed barns with access to an open area. Results showed that age and weight of ram lambs at puberty were significantly affected (P<0.05) by the pre-pubertal growth rate. Ram lambs in the fast growing group were reached to onset puberty firstly at 272.6 days with body weight (BW) 37.1 kg on average then ram lambs in medium group (284.8 days with BW 32.7 kg), while ram lambs in slow growing group were the last (314.1 days with BW 32.5 kg). Blood‎ testosterone‎ concentration at puberty was not significantly different among growing groups (1.494± 0.03 ng/ml on average, ranged from 1.287 to 1.902 ng/ml). Testes measurements from 6 months of age until puberty show that ram lambs in fast growing group had the highest values of testes length, circumference and volume followed by those in medium and slow growing group. Sexual behavioral observation showed that flehmen and mounting behavior were significantly higher for ram lambs in fast growing group (5.63 and 6.75 number/12h) than slow growing group (4.25 and 5.38 number/12h) while in medium growing group were intermediate (4.88 and 5.88 number/12h). From these findings, could be concluded that age, weight and sexual behavioral patterns of Sohagi ram lambs at puberty were affected by pre-pubertal growth rate, and the breeders should strive to achieve good growth rates for their lambs before puberty which led to improving reproductive performance.(AU)

Changes in expression of interferon-stimulated genes and ubiquitin activating enzyme E1-like in ovine thymus during early pregnancy

As the main signal for the maternal recognition in ruminants, interferon-tau (IFNT) stimulates expression of interferon-stimulated genes (ISGs) in uterus and many extrauterine tissues. However, it is unclear that early pregnancy induces expression of signal transducer and activator of transcription 1 (STAT1), myxovirusresistance 1 (Mx1), interferon-gamma-inducible protein 10 (IP-10) and ubiquitin activating enzyme E1-like protein (UBE1L) in maternal thymus. In this study, ovine thymuses were sampled on day 16 of the estrous cycle and on days 13, 16 and 25 of gestation, and the expression of STAT1, Mx1, IP-10 and UBE1L was detected by real-time quantitative PCR, Western blot and immunohistochemistry. The results revealed that the expression of STAT1 and IP-10 reached peaks on day 16 of pregnancy, and expression of Mx1 was enhanced on day 25 of pregnancy, and STAT1 protein was located in the epithelial reticular cells, capillaries and thymic corpuscles. However, expression of UBE1L was declined during early pregnancy. In conclusion, early pregnancy influences expression of STAT1, Mx1, IP-10 and UBE1L in maternal thymus, which may participate in regulation of maternal immune tolerance during early pregnancy in sheep.

Dimethylacetamide alone or in combination with glycerol can be used for cryopreservation of ovine semen

Dimethylacetamide has been included in different extenders for the cryopreservation of semen from species with promising results. The objective of this study was to evaluate the use of dimethylacetamide (DMA) in different concentrations, associated or not with glycerol (GLY), for the cryopreservation of ovine semen, and its effects on in vitro sperm parameters and post-thaw in vivo fertility. Five semen samples of five adult Santa Ines sheep (n=25) were used. The collected ejaculates were divided among the seven treatments for subsequent cryopreservation. The treatments presented different concentrations of DMA and GLY, being divided as G1: GLY 6%; G2: DMA 3%; G3: GLY 5% + DMA 1%; G4: GLY 4% + DMA 2%; G5: GLY 3% + DMA 3%; G6: GLY 2% + DMA 4%; G7: GLY 1% + DMA 5%. %. Post-thawing of the straws, aliquots were evaluated for computerized sperm kinetics (CASA) and plasma membrane integrity, using fluorescent probes and flow cytometry. After the in vitro evaluation of the sperm parameters, in vivo testing was performed by laparoscopic artificial insemination of 72 females. The post-thaw total motility (%) evaluated by CASA were 51.4, 51.4, 50.1, 53.6, 52.3, 52.8 and 46.9, respectively, for the seven groups. And the plasma membrane integrity (%) were 19.7, 28.4, 22.3, 29.4, 24.3, 17.9 and 16.9, respectively. There were no differences (P> 0.05) between the treatments for the parameters of spermatic kinetics and membrane integrity. For females inseminated with semen from the control group (G1, GLY6%), the percentage of pregnant females was 36.1%, a result similar to that obtained with G3 treatment (GLY5% + DMA1%). In conclusion, dimethylacetamide, either alone or in combination with glycerol, can be used for cryopreservation of ovine semen.

Desenvolvimento embrionário/fetal, placentação e glicosaminoglicanos no aparelho reprodutor feminino e na placenta / Embryonic/fetal development, placentation and glycosaminoglycans in the female reproductive tract and placenta

Background: Fetal attachments, placentation and embryonic development have been widely discussed in rodents such as agoutisand cavies, as well as research on glycosaminoglycans (GAGs) in rats and rabbits. Moreover, studies on buffalo, cattle and sheep aredescribed in ruminants, and work has also been reported in sheep with GAGs in placentoma. However, further studies are needed inthis regard, since there are reports of economic losses associated with reproductive failures described for cattle such as changes in thechorion and allantois, and in sheep in which changes between the transition from vitelline to allantois circulation have been discussed.Review: In relation to embryonic development, detailed studies have been described in rodents such as rats (12 days old), desertmouse (15 days old) and agoutis at 30 days. Macroscopic structures such as the cephalic region, nose, optic vesicle, cervical curvature, thoracic and pelvic limbs were observed, as well as microscopic structures such as the pituitary, lung, heart, brain cavity, liver,retina, and ossification regions. There are reports of buffalo and cattle studies in ruminants describing early embryonic development.However, the research in the case of sheep is limited, meaning there is only the ultrasound examination, such as gestational diagnosisand morphometric measurement of the embryonic vesicle. Still, studies with umbilical funicular and placental development of sheepwith different gestational ages can be highlighted. Regarding extraembryonic annexes, four important structures which contributeto embryonic maintenance have been reported. These are called the chorion, amnion, allantois and yolk sac, respectively, and areresponsible for originating the placenta, embryonic protection, collecting metabolic waste and early embryonic nutrition. In...

Changes in expression of interferon-stimulated genes and ubiquitin activating enzyme E1-like in ovine thymus during early pregnancy

As the main signal for the maternal recognition in ruminants, interferon-tau (IFNT) stimulates expression of interferon-stimulated genes (ISGs) in uterus and many extrauterine tissues. However, it is unclear that early pregnancy induces expression of signal transducer and activator of transcription 1 (STAT1), myxovirusresistance 1 (Mx1), interferon-gamma-inducible protein 10 (IP-10) and ubiquitin activating enzyme E1-like protein (UBE1L) in maternal thymus. In this study, ovine thymuses were sampled on day 16 of the estrous cycle and on days 13, 16 and 25 of gestation, and the expression of STAT1, Mx1, IP-10 and UBE1L was detected by real-time quantitative PCR, Western blot and immunohistochemistry. The results revealed that the expression of STAT1 and IP-10 reached peaks on day 16 of pregnancy, and expression of Mx1 was enhanced on day 25 of pregnancy, and STAT1 protein was located in the epithelial reticular cells, capillaries and thymic corpuscles. However, expression of UBE1L was declined during early pregnancy. In conclusion, early pregnancy influences expression of STAT1, Mx1, IP-10 and UBE1L in maternal thymus, which may participate in regulation of maternal immune tolerance during early pregnancy in sheep.(AU)

Dimethylacetamide alone or in combination with glycerol can be used for cryopreservation of ovine semen

Dimethylacetamide has been included in different extenders for the cryopreservation of semen from species with promising results. The objective of this study was to evaluate the use of dimethylacetamide (DMA) in different concentrations, associated or not with glycerol (GLY), for the cryopreservation of ovine semen, and its effects on in vitro sperm parameters and post-thaw in vivo fertility. Five semen samples of five adult Santa Ines sheep (n=25) were used. The collected ejaculates were divided among the seven treatments for subsequent cryopreservation. The treatments presented different concentrations of DMA and GLY, being divided as G1: GLY 6%; G2: DMA 3%; G3: GLY 5% + DMA 1%; G4: GLY 4% + DMA 2%; G5: GLY 3% + DMA 3%; G6: GLY 2% + DMA 4%; G7: GLY 1% + DMA 5%. %. Post-thawing of the straws, aliquots were evaluated for computerized sperm kinetics (CASA) and plasma membrane integrity, using fluorescent probes and flow cytometry. After the in vitro evaluation of the sperm parameters, in vivo testing was performed by laparoscopic artificial insemination of 72 females. The post-thaw total motility (%) evaluated by CASA were 51.4, 51.4, 50.1, 53.6, 52.3, 52.8 and 46.9, respectively, for the seven groups. And the plasma membrane integrity (%) were 19.7, 28.4, 22.3, 29.4, 24.3, 17.9 and 16.9, respectively. There were no differences (P> 0.05) between the treatments for the parameters of spermatic kinetics and membrane integrity. For females inseminated with semen from the control group (G1, GLY6%), the percentage of pregnant females was 36.1%, a result similar to that obtained with G3 treatment (GLY5% + DMA1%). In conclusion, dimethylacetamide, either alone or in combination with glycerol, can be used for cryopreservation of ovine semen.(AU)

Desenvolvimento embrionário/fetal, placentação e glicosaminoglicanos no aparelho reprodutor feminino e na placenta / Embryonic/fetal development, placentation and glycosaminoglycans in the female reproductive tract and placenta

Background: Fetal attachments, placentation and embryonic development have been widely discussed in rodents such as agoutisand cavies, as well as research on glycosaminoglycans (GAGs) in rats and rabbits. Moreover, studies on buffalo, cattle and sheep aredescribed in ruminants, and work has also been reported in sheep with GAGs in placentoma. However, further studies are needed inthis regard, since there are reports of economic losses associated with reproductive failures described for cattle such as changes in thechorion and allantois, and in sheep in which changes between the transition from vitelline to allantois circulation have been discussed.Review: In relation to embryonic development, detailed studies have been described in rodents such as rats (12 days old), desertmouse (15 days old) and agoutis at 30 days. Macroscopic structures such as the cephalic region, nose, optic vesicle, cervical curvature, thoracic and pelvic limbs were observed, as well as microscopic structures such as the pituitary, lung, heart, brain cavity, liver,retina, and ossification regions. There are reports of buffalo and cattle studies in ruminants describing early embryonic development.However, the research in the case of sheep is limited, meaning there is only the ultrasound examination, such as gestational diagnosisand morphometric measurement of the embryonic vesicle. Still, studies with umbilical funicular and placental development of sheepwith different gestational ages can be highlighted. Regarding extraembryonic annexes, four important structures which contributeto embryonic maintenance have been reported. These are called the chorion, amnion, allantois and yolk sac, respectively, and areresponsible for originating the placenta, embryonic protection, collecting metabolic waste and early embryonic nutrition. In...(AU)

Produção in vivo de embriões caprinos e ovinos submetidos ao meio de manutenção ACP® / In vivo production of goat and sheep embryos submitted to the ACP® maintenance médium

The use of ACP® as a means of maintenance in the stages of multiple ovulation and embryo transfer, has not yet been reported in the literature, although ACP® is a plant fluid rich in nutrients. Thus, the objective was to compare the efficiency of ACP® as a substitute for embryo maintenance medium during MOTE biotechnology in goats and sheep. For this, three donor goats, Anglo-Nubian breed and three donor sheep, Dorper breed were used. Fifteen recipient females of each species were used. The donors were submitted to the superovulation protocol and inseminated, and later the embryos were collected. After harvesting, the embryos were submitted to the control maintenance medium, TQC Holding® or ACP® maintenance medium. The recipients were synchronized simultaneously with the donors, and after 30 days the pregnancy diagnosis was made. It was obtained 10% of pregnant in goats and 75% of pregnant in sheep, whose embryos were submitted to the ACP® maintenance medium before the innovation. It is concluded that the means of maintenance of ACP® embryos did not negatively influence the embryonic quality and the development of pregnancy in small ruminants.

Understanding the trade-off between the environment and fertility in cows and ewes

The environment contributes to production diseases that in turn badly affect cow performance, fertility and culling. Oestrus intensity is lower in lame cows, and in all cows 26% potential oestrus events are not expressed (to avoid getting pregnant). To understand these trade-offs, we need to know how animals react to their environment and how the environment influences hypothalamus-pituitary-adrenal axis (HPA) interactions with the hypothalamus-pituitary-ovarian axis (HPO). Neurotransmitters control secretion of GnRH into hypophyseal portal blood. GnRH/LH pulse amplitude and frequency drive oestradiol production, culminating in oestrus behaviour and a precisely-timed GnRH/LH surge, all of which are disrupted by poor environments. Responses to peripheral neuronal agents give clues about mechanisms, but do these drugs alter perception of stimuli, or suppress consequent responses? In vitro studies confirm some neuronal interactions between the HPA and HPO; and immuno-histochemistry clarifies the location and sequence of inter-neurone activity within the brain. In both species, exogenous corticoids, ACTH and/or CRH act at the pituitary (reduce LH release by GnRH), and hypothalamus (lower GnRH pulse frequency and delay surge release). This requires inter-neurones as GnRH cells do not have receptors for HPA compounds. There are two (simultaneous, therefore fail-safe?) pathways for CRH suppression of GnRH release via CRH-Receptors: one being the regulation of kisspeptin/dynorphin and other cell types in the hypothalamus, and the other being the direct contact between CRH and GnRH cell terminals in the median eminence. When we domesticate animals, we must provide the best possible environment otherwise animals trade-off with lower production, less intense oestrus behaviour, and impaired fertility. Avoiding life-time peri-parturient problems by managing persistent lactations in cows may be a worthy trade-off on both welfare and economic terms – better than the camouflage use of drugs/hormones/feed additives/intricate technologies? In the long term, getting animals and environment in a more harmonious balance is the ultimate strategy.

Understanding the trade-off between the environment and fertility in cows and ewes

The environment contributes to production diseases that in turn badly affect cow performance, fertility and culling. Oestrus intensity is lower in lame cows, and in all cows 26% potential oestrus events are not expressed (to avoid getting pregnant). To understand these trade-offs, we need to know how animals react to their environment and how the environment influences hypothalamus-pituitary-adrenal axis (HPA) interactions with the hypothalamus-pituitary-ovarian axis (HPO). Neurotransmitters control secretion of GnRH into hypophyseal portal blood. GnRH/LH pulse amplitude and frequency drive oestradiol production, culminating in oestrus behaviour and a precisely-timed GnRH/LH surge, all of which are disrupted by poor environments. Responses to peripheral neuronal agents give clues about mechanisms, but do these drugs alter perception of stimuli, or suppress consequent responses? In vitro studies confirm some neuronal interactions between the HPA and HPO; and immuno-histochemistry clarifies the location and sequence of inter-neurone activity within the brain. In both species, exogenous corticoids, ACTH and/or CRH act at the pituitary (reduce LH release by GnRH), and hypothalamus (lower GnRH pulse frequency and delay surge release). This requires inter-neurones as GnRH cells do not have receptors for HPA compounds. There are two (simultaneous, therefore fail-safe?) pathways for CRH suppression of GnRH release via CRH-Receptors: one being the regulation of kisspeptin/dynorphin and other cell types in the hypothalamus, and the other being the direct contact between CRH and GnRH cell terminals in the median eminence. When we domesticate animals, we must provide the best possible environment otherwise animals trade-off with lower production, less intense oestrus behaviour, and impaired fertility. Avoiding life-time peri-parturient problems by managing persistent lactations in cows may be a worthy trade-off on both welfare and economic terms better than the camouflage use of drugs/hormones/feed additives/intricate technologies? In the long term, getting animals and environment in a more harmonious balance is the ultimate strategy.(AU)