The landscape of long non-coding RNA expression in the goat brain

The brain regulates multiple metabolic processes, such as food intake, energy expenditure, insulin secretion, hepatic glucose production and glucose/fatty acid metabolism in adipose tissue, which are fundamental for the maintenance of energy and glucose homeostasis during lactation and pregnancy. Besides, brain expression has a fundamental impact on the development of maternal behavior. Although brain functions are partly regulated by long non-coding RNAs (lncRNAs), their expression profiles have not been characterized in depth in any ruminant species. We have sequenced the transcriptome of 12 brain tissues from 3 1-mo pregnant and 4 non-pregnant goats to investigate their lncRNA expression patterns. Between 4,363 (adenohypophysis) and 4,604 (olfactory bulb) lncRNAs were expressed in brain tissues, leading to establish a set of 794 already annotated lncRNAs and 5,098 novel lncRNA candidates. The detected lncRNAs shared features with those of other mammals, and tissue-specific lncRNAs were enriched in brain development-related terms. Differential expression analyses between 1 mo-pregnant and non-pregnant goats showed that the lncRNA expression profiles of certain brain regions experience substantial changes associated with early pregnancy (238 lncRNAs are differentially expressed in the olfactory bulb), while others do not. Enrichment analysis showed that differentially expressed lncRNAs from the olfactory bulb are co-expressed with genes previously linked to behavioral changes related to pregnancy. These findings provide a first characterization of the landscape of lncRNA expression in the goat brain and provides valuable clues to understand the molecular events triggered by early pregnancy in the central nervous system.

Effect of Honey, Coenzyme Q10, and β-Carotene/α-Tocopherol as Novel Additives in Rabbit-Sperm Cryopreservation Extender

The effectiveness of rabbit-sperm cryopreservation is still below average compared to other domestic species. After the sperm cryopreservation process, post-thawing parameters like motility and membrane integrity are significantly compromised. The use of new extender constituents is an approach that can be used to improve the effectiveness of cryopreservation. Accordingly, we used honey (1.25, 2.5, 5, and 10%), coenzyme Q10 (100 and 200 μM), and β-carotene/α-tocopherol (500 μM/620 μM and 250 μM/310 μM) as candidate components for rabbit-sperm extenders during cryopreservation. Ejaculates from commercial adult rabbit bucks (n = 5) were cryopreserved using conventional freezing. Several post-thawing sperm parameters were assessed, including total motility, membrane integrity, viability, nuclear membrane integrity, acrosome reaction, and mitochondrial membrane potential and activation. Additionally, we performed hormonal analyses of the seminal plasma. Moreover, we analyzed the post-thawing levels of a molecular marker of sperm quality, proAKAP4, which was used in rabbits for the first time. Our findings showed that the 2.5% honey supplementation increased the post-thawing sperm motility (13.75 ± 3.75%) compared to the greater concentrations employed. However, the post-thawing motility was negatively affected by the coenzyme Q10 (0%, in both groups) but was not affected by the β-carotene/α-tocopherol supplementation (22 ± 18.15%, and 11.67 ± 10.17%). In conclusion, the cryopreservation protocols of this study did not help to maintain the sperm parameters after thawing. Further studies are required to identify novel protocols to mitigate the damage caused to rabbit sperm during cryopreservation.

A protein-coding gene expression atlas from the brain of pregnant and non-pregnant goats

Background: The brain is an extraordinarily complex organ with multiple anatomical structures involved in highly specialized functions related with behavior and physiological homeostasis. Our goal was to build an atlas of protein-coding gene expression in the goat brain by sequencing the transcriptomes of 12 brain regions in seven female Murciano-Granadina goats, from which three of them were 1-month pregnant. Results: Between 14,889 (cerebellar hemisphere) and 15,592 (pineal gland) protein-coding genes were expressed in goat brain regions, and most of them displayed ubiquitous or broad patterns of expression across tissues. Principal component analysis and hierarchical clustering based on the patterns of mRNA expression revealed that samples from certain brain regions tend to group according to their position in the anterior-posterior axis of the neural tube, i.e., hindbrain (pons and medulla oblongata), midbrain (rostral colliculus) and forebrain (frontal neocortex, olfactory bulb, hypothalamus, and hippocampus). Exceptions to this observation were cerebellum and glandular tissues (pineal gland and hypophysis), which showed highly divergent mRNA expression profiles. Differential expression analysis between pregnant and non-pregnant goats revealed moderate changes of mRNA expression in the frontal neocortex, hippocampus, adenohypophysis and pons, and very dramatic changes in the olfactory bulb. Many genes showing differential expression in this organ are related to olfactory function and behavior in humans. Conclusion: With the exception of cerebellum and glandular tissues, there is a relationship between the cellular origin of sampled regions along the anterior-posterior axis of the neural tube and their mRNA expression patterns in the goat adult brain. Gestation induces substantial changes in the mRNA expression of the olfactory bulb, a finding consistent with the key role of this anatomical structure on the development of maternal behavior.

NR3C1 and glucocorticoid-regulatory genes mRNA and protein expression in the endometrium and ampulla during the bovine estrous cycle

The bovine reproductive tract exhibits changes during the estrous cycle modulated by the interplay of steroid hormones. Glucocorticoids can be detrimental when stress-induced but are relevant at baseline levels for appropriate reproductive function. Here, an analysis of quantitative real-time PCR was performed to study the bovine glucocorticoid-related baseline gene transcription in endometrial and ampullar tissue samples derived from three time points of the estrous cycle, stage I (Days 1-4), stage III (Days 11-17) and stage IV (Days 18-20). Our results revealed expression differences during stages, as expression observed in the ampulla was higher during the post-ovulatory phase (stage I), including the glucocorticoid receptor NR3C1, and some of its regulators, involved in glucocorticoid availability (HSD11B1 and HSD11B2) and transcriptional actions (FKBP4 and FKBP5). In contrast, in the endometrium, higher expression of the steroid receptors was observed during the late luteal phase (stage III), including ESR1, ESR2, PGRMC1 and PGRMC2, and HSD11B1 expression decreased, while HSD11B2 increased. Moreover, at protein level, FKBP4 was higher expressed during the late luteal phase, and NR3C1 during the pre-ovulatory phase (stage IV). These results suggest that tight regulation of the glucocorticoid activity is promoted in the ampulla, when reproductive events are taking place, including oocyte maturation. Moreover, most expression changes in the endometrium were observed during the late luteal phase, and may be related to the embryonic maternal recognition. In conclusion, the glucocorticoid regulation changes across the estrous cycle and may be playing a role on the reproductive events occurring in the bovine ampulla and endometrium.

The mRNA expression of the three major described cold-inducible proteins, including CIRBP, differs in the bovine endometrium and ampulla during the estrous cycle

The cold-inducible proteins (CIPs) are essential for post-transcriptional gene regulation playing diverse tissue-specific roles in maintaining normal cellular function and morphogenesis. The potential implications of CIPs in reproductive events raise questions about their role in the physiology of the bovine reproductive tract. However, the expression changes of CIPs during the bovine estrous cycle have not been studied so far. Here, we hypothesized that the bovine estrous cycle could affect the mRNA expression of the CIPs and other candidate transcripts in the reproductive tract. This study aimed to examine estrous cycle-dependent mRNA expression patterns in the bovine endometrium and ampulla of three of the major described CIPs (CIRBP, RBM3, SRSF5), a set of inflammatory cytokines (IL-10, IL-18, IL-1β), and other candidate genes (IL-10RA, IL-10RB, BCL2, NLRP3, STAT1, STAT3, STAT5A, STAT6). Endometrial and ampullar tissues were assessed by RT-qPCR. Additionally, the mRNA expression levels were correlated among them and with follicular progesterone and estradiol concentrations. The transcript levels of CIPs increased in the endometrium during stage III (Days 11-17) compared to stage I (Days 1-4) and IV (Days 18-20). In the ampulla, the mRNA expression of CIRBP increased during the late luteal phase (stage III), but no differences in the expression of other CIPs were observed. This study expands the current knowledge regarding mRNA expression in the endometrium and oviductal ampulla of cycling heifers, focusing mainly on the CIPs. A better understanding of the mechanisms within the uterus and oviduct during the estrous cycle is crucial to improving the fertility rate.

Exopolysaccharide ID1 Improves Post-Warming Outcomes after Vitrification of In Vitro-Produced Bovine Embryos

This study aimed to assess the cryoprotectant role of exopolysaccharide (EPS) ID1, produced by Antarctic Pseudomonas sp., in the vitrification of in vitro-produced (IVP) bovine embryos. IVP day 7 (D7) and day 8 (D8) expanded blastocysts derived from cow or calf oocytes were vitrified without supplementation (EPS0) or supplemented with 10 µg/mL (EPS10) or 100 µg/mL (EPS100) EPS ID1. The effect of EPS ID1 was assessed in post-warming re-expansion and hatching rates, differential cell count, apoptosis rate, and gene expression. EPS100 re-expansion rates were significantly higher than those observed for the EPS0 and EPS10 treatments, regardless of culture length or oocyte source. EPS100 hatching rate was similar to the one of the fresh blastocysts except for those D7 blastocysts derived from calf oocytes. No differences were observed among EPS ID1 treatments when the inner cell mass, trophectoderm, and total cell number were assessed. Although apoptosis rates were higher (p ≤ 0.05) in vitrified groups compared to fresh embryos, EPS100 blastocysts had a lower number (p ≤ 0.05) of apoptotic nuclei than the EPS0 or EPS10 groups. No differences in the expression of BCL2, AQP3, CX43, and SOD1 genes between treatments were observed. Vitrification without EPS ID1 supplementation produced blastocysts with significantly higher BAX gene expression, whereas treatment with 100 µg/mL EPS ID1 returned BAX levels to those observed in non-vitrified blastocysts. Our results suggest that 100 µg/mL EPS ID1 added to the vitrification media is beneficial for embryo cryopreservation because it results in higher re-expansion and hatching ability and it positively modulates apoptosis.

Evaluation of Fecal Glucocorticoid Metabolite Levels in Response to a Change in Social and Handling Conditions in African Lions (Panthera leo bleyenberghi)

Simple Summary

Non-invasive determination of cortisol metabolite concentrations in feces is widely used to evaluate the influence of housing and handling conditions on the stress physiology of wildlife in captivity. The present study aimed to assess the physiological response of a lion pride to a change in management and social conditions after the death of the dominant male of the pride. Before the dominant male died, weekly management routines between the indoor and outdoor enclosures were conducted to avoid cohabitation problems between the two males of the pride. After the death of the dominant male, these weekly management dynamics ceased, leading to a decrease in the daily management routine of the lion pride. An individualized sampling of the animals through the utilization of indigestive markers was conducted, and fecal samples were collected before and after the death of the dominant male. Significant lower cortisol metabolite concentrations in feces were detected after the death of the dominant male, suggesting a positive impact of a decrease in daily management routines, together with a more stable social environment. In addition, assessment of individualized hormone concentrations throughout the study revealed variable physiological responses among lions, providing evidence of the importance of monitoring hormonal profiles individually.

Abstract

Monitoring the hypothalamic–pituitary–adrenal (HPA) axis through determination of fecal cortisol metabolite (FCM) levels is a non-invasive method useful for understanding how handling and social conditions may affect the physiological status of zoo animals. The present study used FCM analysis to evaluate whether the HPA axis activity of a lion pride was modified by a change in social and handling conditions after the death of the dominant male. Five African lions (Panthera leo bleyenberghi), two males and three females, were included in the study. Fecal samples were collected before and after the death of the dominant male. To avoid cohabitation conflicts between males before the dominant male died, subgroups were established and subjected to weekly changes between indoor and outdoor facilities. After the death of the dominant male, these management dynamics ceased, and the remaining four lions were kept together outdoors. Significant lower group FCM concentrations (p < 0.001) were detected after the decease of the dominant male, probably associated with a decrease in daily handling, together with a more stable social environment. Overall, the present study indicates the effect of different management scenarios on the HPA axis activity and differentiated physiological responses to the same situation between individuals.

Intestinal Parasites and Fecal Cortisol Metabolites in Multi-Unowned-Cat Environments: The Impact of Housing Conditions

Simple Summary

Multi-unowned-cat environments can be highly stressful for cats, and infectious and parasite diseases spread quickly and are difficult to prevent. This study aimed to determine the occurrence of intestinal parasites and fecal cortisol metabolites (FCM) in cat feces collected from different multi-cat environments and assess the effect of housing conditions on intestinal parasites and FCM levels in order to develop more efficient control strategies. Cat fecal samples from rescue shelters, catteries and feline colonies were analyzed with coprological methods to detect intestinal parasite patency and determine FCM. Helminth infection was mainly detected in free-roaming cats. In confined cats, protozoa infections were more likely detected in shelter cats than in cattery cats. Exposure to dogs was associated with parasite infection and cats highly exposed to dogs with visual contact and audible barking showed higher intestinal protozoa prevalence than cats that were not exposed to dogs. FCM levels were correlated with enclosure size and protozoa infection. Reducing stress by improving housing in terms of enclosure size and avoiding exposure to dogs may have an impact on the occurrence of intestinal parasites, especially protozoa.

Abstract

Housing conditions were assessed in different unowned multi-cat management models in order to evaluate their impact on the occurrence of intestinal parasites and fecal cortisol metabolite (FCM) levels. Fresh stool fecal samples were collected from rescue shelters, catteries and feline colonies for coprological analyses in order to detect intestinal parasite patency and fecal cortisol metabolites. A questionnaire provided information about the facilities, management and housing conditions of cats, including information about dog exposure, enclosure size, environment enrichment and changes to group composition. Overall, intestinal parasite infection was detected in 58.2% of fecal samples collected. The occurrence of intestinal parasites detected in free-roaming cats was 82.2%, mainly due to helminth infection. The parasite infection rate was 57.3% in rescue shelters and 34.6% in catteries. In confined cats, protozoa infection was more likely detected in rescue shelters than in catteries (RR = 2.02 (1.30–3.14), p = 0.0012). Although the FCM values were very variable between cats, the enclosure size and parasite infection were correlated with the average FCM. A small enclosure size was correlated with high fecal cortisol metabolites (p = 0.016). Protozoa-positive samples showed higher FCM levels than negative samples (p = 0.0150). High dog exposure was statistically associated with protozoa infection (p = 0.0006). The results indicated that improving housing, especially in terms of floor space and avoiding dog exposure, reduces stress and can thus be applied to make control strategies in multi-unowned-cat environments more efficient, especially when cats are confined.

32 An approach to invitro oocyte maturation and fertilization in threatened Saharan Dorcas gazelle (Gazella dorcas osiris) using frozen-thawed epididymal sperm cells

The Dorcas gazelle (Gazella dorcas), in the family Bovidae, is one of the smallest species of the genus Gazella. Its population is decreasing and it is classified as vulnerable by the International Union of Conservation of Nature Red List of Threatened Species. The subspecies Saharan Dorcas gazelle (G. dorcas osiris), originating in the central-western Saharan and Sahel regions, is almost extinct in the wild because of over-hunting. Thereon, assisted reproductive techniques (ARTs) could help in its population management. Here, we performed invitro maturation (IVM) of oocytes recovered from an adult female of Saharan Dorcas gazelle (10 years old) to attempt IVF with frozen-thawed epididymal sperm cells from an adult male (9 years old) of the same subspecies, following protocols for ARTs in cattle. Epididymal sperm was obtained after postmortem examination by cannulation of vas deferens with commercial semen extender Gent A (Minitub). Motility features were assessed using a computer-assisted sperm analysis system (Proiser SL), and viability was evaluated using eosin/nigrosin staining. After collection, viability (88.3%), total (17.8%) and progressive (8.7%) motility were assessed. A total of 820.5×106 sperm cells was obtained and diluted (1:1) in a semen extender with permeable cryoprotectants (Gent B, Minitub). Then, the sample was refrigerated in straws (200×106 mL−1; 0.5mL) at 4°C for 1h and exposed to liquid nitrogen vapors (LN2) for 10min before being directly plunged into and kept on LN2. A total of 35 oocytes were recovered by slicing, 27 of which were selected for IVM (24h, 38.5°C, 5% CO2 in humidified air). Motile sperm were obtained by centrifugation of thawed semen (10min, 1000×g) by performing a density gradient (BoviPure, Nidacon). Post-thawing viability (72.9%) and total (14%) and progressive (4%) motility were evaluated just before IVF. After IVM, 17 oocytes were incubated for IVF for 20h with 1×106 thawed sperm cells mL−1 (although the first polar body extrusion was observed only in 5 of the 17 oocytes before IVF; 29.4%). Also, 7 oocytes selected for IVM were vitrified and kept for the genetic bank, and 3 were fixed. Thereafter, all oocytes that underwent IVF were incubated for invitro embryo culture (38.5°C, 5% CO2, 5% O2 in humidified air) to avoid discarding any potential zygote. Cleavage was assessed at 48h post-IVF. From those, only 2 oocytes successfully achieved IVF out of the 5 that showed first polar body extrusion (40%), although cleavage was asymmetric and embryos did not progress. The rest of oocytes (12) did not achieved IVM, IVF, or cleavage. Results suggest that optimal protocols and appropriate individualized conditions for vulnerable nondomestic ungulates are required for successful ARTs. Future efforts are needed to improve preservation strategies for the gametes/embryo conservation of endangered species. JG and MRC contributed equally to this work. JG is supported by AGAUR (2018 FI_B 00236) and MRC by FPU (Training for Academic Staff) (FPU15/06029).

Seminal Plasma Triggers the Differential Expression of the Glucocorticoid Receptor (NR3C1/GR) in the Rabbit Reproductive Tract

Rabbits are interesting as research animal models for reproduction, due to their condition of species of induced ovulation, with the release of endogenous gonadotropin-releasing hormone (GnRH) due to coitus. Glucocorticoid (GC) signaling, crucial for physiological homeostasis, is mediated through a yet unclear mechanism, by the GC receptor (NR3C1/GR). After mating, the female reproductive tract undergoes dynamic modifications, triggered by gene transcription, a pre-amble for fertilization and pregnancy. This study tested the hypothesis that when ovulation is induced, the expression of NR3C1 is influenced by sperm-free seminal plasma (SP), similarly to after mating (whole semen), along the different segments of the internal reproductive tract of female rabbits. Semen (mating) was compared to vaginal infusion of sperm-free SP (Experiment 1), and changes over time were also evaluated, i.e., 10, 24, 36, 68, and 72 h post-mating, corresponding to specific stages, i.e., ovulation, fertilization, and the interval of early embryo development up to the morula stage (Experiment 2). All does were treated with GnRH to induce ovulation. Samples were retrieved from seven segments of the reproductive tract (from the cervix to infundibulum), at 20 h post-mating or sperm-free SP infusion (Experiment 1) or at 10, 24, 36, 68, and 72 h post-mating (Experiment 2). Gene expression of NR3C1 was analyzed by qPCR. Results showed an increase in NR3C1 expression in the infundibulum compared to the other anatomical regions in the absence of spermatozoa when sperm-free SP infusion was performed (Experiment 1). Moreover, during the embryo transport through the oviduct, the distal isthmus was time-course upregulated, especially at 72 h, when morulae are retained in this anatomical region, while it was downregulated in the distal uterus at 68 h (Experiment 2). The overall results suggest that NR3C1, the GC receptor gene, assessed in the reproductive tract of does for the first time, shows differential expression changes during the interval of oviductal and uterine embryo transport that may imply a relevant role of the GC action, not only close to the site of ovulation and fertilization, but also in the endometrium.

Cryoprotectant role of exopolysaccharide of Pseudomonas sp. ID1 in the vitrification of IVM cow oocytes

Biological molecules isolated from organisms that live under subzero conditions could be used to protect oocytes from cryoinjuries suffered during cryopreservation. This study examined the cryoprotectant role of exopolysaccharides of Pseudomonas sp. ID1 (EPS ID1) in the vitrification of prepubertal and adult cow oocytes. IVM oocytes were vitrified and warmed in media supplemented with 0, 1, 10, 100 or 1000µgmL-1 EPS ID1. After warming, oocytes were fertilised and embryo development, spindle morphology and the expression of several genes in Day 8 blastocysts were assessed. Vitrification led to significantly lower proportion of prepubertal oocytes exhibiting a normal spindle configuration. In fresh control oocytes and most groups of vitrified adult oocytes, similar percentages of oocytes with a normal spindle configuration were observed. Percentages of Day 8 blastocysts were similar for prepubertal oocytes vitrified in the absence or presence of 1 or 10µgmL-1 EPS ID1 and for adult oocytes vitrified in the presence of 10µgmL-1 EPS ID1 compared with non-vitrified oocytes. EPS ID1 supplementation had no effect on solute carrier family 2 member 3 (SLC2A3), ubiquitin-conjugating enzyme E2A (UBE2A) and histone deacetylase 1 (HDAC1) expression in Day 8 blastocysts form adult oocytes. However, supplementation with 10 and 100µgmL-1 EPS ID1 led to increased expression of genes involved in epigenetic modifications (DNA methyltransferase 3 alpha (DNMT3A) and K (lysine) acetyltransferase 2A (KAT2A)) and apoptosis (BCL2 associated X apoptosis regulator (BAX) and BCL2-like 1 (BCL2L1)). The lowest BAX:BCL2L1 ratio was found in the 10µgmL-1 EPS ID1-supplemented group. The results suggest that 10µgmL-1 EPS ID1 added to vitrification and warming media may help protect bovine oocytes against cryodamage.

Glutathione Ethyl Ester Protects In Vitro-Maturing Bovine Oocytes against Oxidative Stress Induced by Subsequent Vitrification/Warming

This study aimed to examine whether the addition of glutathione ethyl ester (GSH-OEt) to the in vitro maturation (IVM) medium would improve the resilience of bovine oocytes to withstand vitrification. The effects of GSH-OEt on spindle morphology, levels of reactive oxygen species (ROS), mitochondrial activity and distribution, and embryo developmental potential were assessed together with the expression of genes with a role in apoptosis (BAX, BCL2), oxidative-stress pathways (GPX1, SOD1), water channels (AQP3), implantation (IFN-τ) and gap junctions (CX43) in oocytes and their derived blastocysts. Vitrification gave rise to abnormal spindle microtubule configurations and elevated ROS levels. Supplementation of IVM medium with GSH-OEt before vitrification preserved mitochondrial distribution pattern and diminished both cytoplasmic and mitochondrial ROS contents and percentages of embryos developing beyond the 8-cell stage were similar to those recorded in fresh non-vitrified oocytes. Although not significantly different from control vitrified oocytes, vitrified oocytes after GSH-OEt treatment gave rise to similar day 8-blastocyst and hatching rates to fresh non-vitrified oocytes. No effects of GSH-OEt supplementation were noted on the targeted gene expression of oocytes and derived blastocysts, with the exception of GPX1, AQP3 and CX43 in derived blastocysts. The addition of GSH-OEt to the IVM medium before vitrification may be beneficial for embryo development presumably as the consequence of additional anti-oxidant protection during IVM.

Effect of season on the in vitro fertilizing ability of frozen-thawed Spanish bovine spermatozoa

The purpose of the present study was to evaluate the effects of season on the in vitro fertilizing ability of bovine spermatozoa and subsequent embryo development. Bovine oocytes were matured and fertilized in vitro with Holstein dairy bull sperm cells collected and frozen in different seasons (winter, spring, and summer). On d 2 and 8 postinsemination, cleavage and blastocyst rates, respectively, were recorded; the blastocysts were graded for morphology. The number of sperm cells binding to the zona pellucida of oocytes, together with the number of nuclei in the developing blastocysts, were assessed after staining with Hoechst. No significant differences were observed among seasons in cleavage and embryo development rate. However, the proportion of "advanced blastocysts" was significantly higher in spring compared with winter and summer, with a corresponding decrease in the proportion of early blastocysts in spring compared with winter and summer. The number of sperm cells binding per oocyte was significantly lower in the oocytes inseminated with sperm samples collected in summer compared with winter or spring. Moreover, a significant interaction was observed in the number of sperm cells binding per oocyte between bull and season. Although no significant differences were observed among seasons in the number of nuclei per blastocyst, a significant interaction was observed between bull and season for this variable. Embryo development rate in in vitro fertilization appeared to be affected by season of semen collection, with sperm samples collected in spring being associated with a higher proportion of advanced blastocysts and better morphology than those collected at other times of the year.

Temporary Relocation during Rest Periods: Relocation Stress and Other Factors Influence Hair Cortisol Concentrations in Horses

Horse transportation for temporary relocation during rest periods is a common and widespread practice among horse owners, either from sport competition or working tasks. This study aimed to determine the effect of a relocation period and the multiple factors associated with a rest period on hair cortisol concentrations (HCCs) in horses. Additionally, this study reports the seasonal effect on HCCs and hair growth over a year. Thirteen police horses, Pure Spanish stallions of various ages (5-13 y), were selected to participate in this study. Hair sample collection was carried out approximately every 30 d for seven months (Study 1) and a year (Study 2). Cortisol determinations were performed by enzyme immunoassay. Interestingly, Study 1 revealed that relocated horses (n = 4) exhibited elevated HCCs compared with control horses (n = 4) after the relocation period (p < 0.05). Study 2 (n = 5) showed higher HCCs during summer compared with autumn and winter, and higher hair growth rates in winter compared with the other seasons (p < 0.05). Relocated horses had higher HCCs, suggesting a change in their welfare status, probably related to the sudden change in their surrounding conditions. However, these results should be interpreted cautiously due to the low sample size used. The nature of the relationship between HCCs and horse welfare needs to be further examined.

Induction of CIRBP expression by cold shock on bovine cumulus-oocyte complexes

The aim of this study was to induce the cold-inducible RNA-binding protein (CIRBP) expression on cumulus-oocyte complexes (COCs) through exposure to a sub-lethal cold shock and determine the effects of hypothermic temperatures during the in vitro maturation of bovine oocytes. Nuclear maturation, cortical granule redistribution and identification of cold-inducible RNA-binding protein (CIRBP) were assessed after 24 hr of in vitro maturation of control (38.5°C) and cold-stressed oocytes (33.5°C). The presence of CIRBP was assessed by Western blot in COCs or denuded oocytes and their respective cumulus cells. Based on the odds ratio, cold-stressed oocytes presented higher abnormal cytoplasmic distribution of cortical granules and nuclear maturation than the control group. Although CIRBP was detected in both control and cold-stressed groups, cold-stressed COCs had 2.17 times more expression of CIRBP than control COCs. However, when denuded oocytes and cumulus cells were assessed separately, CIRBP only was detected in cumulus cells in both groups. In conclusion, cold shock induced CIRBP expression, but it negatively affected nuclear maturation and cortical granule distribution of bovine oocytes. Moreover, the expression of CIRBP was only identified in cumulus cells but not in oocytes.

Chicken seminal fluid lacks CD9- and CD44-bearing extracellular vesicles

The avian seminal fluid (SF) is a protein-rich fluid, derived from the testis, the rudimentary epididymis and, finally, from the cloacal gland. The SF interacts with spermatozoa and the inner cell lining of the female genital tract, to modulate sperm functions and female immune responsiveness. Its complex proteome might either be free or linked to extracellular vesicles (EVs) as it is the case in mammals, where EVs depict the tetraspanin CD9; and where those EVs derived from the epididymis (epididymosomes) also present the receptor CD44. In the present study, sperm-free SF from Red Jungle Fowl, White Leghorn and an advanced intercross (AIL, 12th generation) were studied using flow cytometry of the membrane marker tetraspanin CD9, Western blotting of the membrane receptor CD44 and electron microscopy in non-enriched (whole SF) or enriched fractions obtained by precipitation using a commercial kit (Total Exosome Precipitation Solution). Neither CD9- nor CD44 could be detected, and the ultrastructure confirmed the relative absence of EVs, raising the possibility that avian SF interacts differently with the female genitalia as compared to the seminal plasma of mammals.

28 Short equilibration improves vitrification of invitro-produced bovine embryos using VitTrans device

For the successful application of vitrification technology to field conditions, the procedures for the warming and transfer of the cryopreserved bovine embryos should be as simple as possible. The device VitTrans, designed by our group, enables warming/dilution of embryos and their transfer directly to recipient females in field conditions (Morato and Mogas 2014 Cryobiology 68, 288). VitTrans vitrification protocol consists of an incubation in equilibration solution during 12min followed by an exposure of 40s to vitrification solution. However, there are other reports using similar vitrification devices where equilibration length is shorter than ours. This study aimed to improve VitTrans methodology by comparing two vitrification protocols: short equilibration (SE) and long equilibration (LE). A total of 63 invitro-produced Day 7 blastocysts (IETS stage code 7) were randomly placed in an equilibration solution with 7.5% ethylene glycol + 7.5% dimethyl sulfoxide in holding medium (tissue culture medium-199 HEPES + 20% fetal calf serum) for either 3min (SE) or 12min (LE). Then, blastocysts were transferred to vitrification solution (15% ethylene glycol + 15% dimethyl sulfoxide + 0.5M sucrose in holding medium) for 40s, loaded onto the VitTrans device, plunged into liquid nitrogen, and covered with a 0.5mL straw. Fresh nonvitrified blastocysts (n=30) were set as control. For warming, the VitTrans was quickly submerged into a water bath at 45°C, while a syringe containing 0.3mL of diluting solution (0.5M sucrose in holding medium) at 45°C was injected through the hollow of the device. Blastocysts were then transferred to synthetic oviductal fluid medium and cultured for 24h at 38.5% in a 5% CO2 and 5% O2 environment in a humidified atmosphere. Re-expansion rates were recorded 3 and 24h after warming. Blastocysts were fixed and stained with SOX2 (Invitrogen) for inner cell mass (ICM) count, TUNEL (Roche) for apoptosis index assessment, and DAPI (Vector Laboratories) for total cell count (TCC). Images were captured using a Leica TCS SP5 confocal microscope (Leica Microsystems) and examined with Imaris 9.2 software (Oxford Instruments). Blastocyst survival rates were compared between groups using chi-squared test. Blastocyst TCC, ICM count, and apoptosis indices were analysed using analysis of variance. Significance was set at P ≤ 0.05. No differences were observed in re-expansion rate at 3h postwarming (61.3 and 59.4% for SE and LE, respectively). However, significantly higher re-expansion rates were found after 24h of culture for the blastocysts of the SE group (74.2%) when compared with the blastocysts of the LE group (65.7%). Blastocysts vitrified using the LE protocol produced the lowest TCC (115±5.9; P ≤ 0.05), whereas TCC of the SE (152±9.7) and fresh control (138±8.6) treatments were similar. No differences were found in ICM count among groups. Nevertheless, apoptosis index was higher (P ≤ 0.05) in both vitrification groups when compared with fresh control. These results indicate that short equilibration vitrification not only improves VitTrans outcomes but adds efficiency by taking less time to perform. Supported by MCIU, Spain (Project AGL2016-79802-P and Grant BES-2017-081962).

33 Assessment of spindle morphology and reactive oxygen species production after vitrification of bovine oocytes following invitro maturation in the presence of glutathione ethyl ester

Oocyte cryopreservation by vitrification affects spindle integrity and causes oxidative stress induced by reactive oxygen species (ROS). Glutathione (GSH) ensures the correct assembly of microtubules, prevents ROS from attacking tubulin assembly, and ensures normal spindle function during meiosis. We hypothesised that addition of GSH ethyl ester (GSH-OEt), a cell-permeable GSH donor, to IVM medium before vitrification may improve oocyte cryotolerance by maintaining spindle morphology and preventing ROS production. For the IVM, viable cumulus-oocyte complexes were randomly distributed into two groups: 1) control: conventional IVM media with tissue culture medium-199 + 20% fetal calf serum + epidermal growth factor and 2) GSH-OEt: IVM medium supplemented with 5mM GSH-OEt at 38.5°C in a 5% CO2 humidified air atmosphere. After 22h of IVM, half of the oocytes from each group were vitrified/warmed using the Cryotop method (Kitazato Corp.). After 24h of IVM, oocytes were denuded, fixed, and microtubule and chromosome distribution were analysed by immunofluorescence. To measure ROS, oocytes were denuded and incubated in 5μM 2′,7′-dichlorodihydrofluorescein diacetate. Fluorescence was acquired, and resulting images were quantified with ImageJ software. A linear mixed effect followed by a pairwise comparison test (Tukey adjustment) were performed to analyse differences in meiotic spindle configuration and ROS production (P&lt;0.05). No significant differences in percentages of MII or normal spindle configuration were observed among treatments. Treatment with GSH-OEt before vitrification resulted in similar percentages of abnormal spindle configuration to control oocytes, whereas vitrified oocytes showed significantly higher percentages of abnormal spindle configuration relative with control oocytes (Table 1). When the content of ROS was measured, vitrification resulted in significantly higher levels (15.1E+06±1.2E+06; P&lt;0.05) when compared with other treatments. However, oocytes vitrified after IVM with GSH-OEt (11.8E+06±0.6E+06) showed similar ROS levels to control (10.7E+06±0.2E+06) and GSH-OEt (10.0E+06±0.1E+06) groups. In conclusion, addition of GSH-OEt to IVM before vitrification did not have detrimental effects on spindle morphology and was able to reduce ROS content. Further experiments are warranted to assess whether the addition of GSH-OEt to IVM medium can improve oocyte development competence after vitrification. Table 1.Assessment of spindle morphology after oocyte vitrification (VIT) following IVM in the presence of glutathione ethyl ester (GSH-OEt) Item n MII (%) Spindle configuration (%) Chromosome distribution (%) Normal Abnormal Absent Dispersed Decondensed Absent Control 127 79.4±92 74.1±4.4 16.2±5.6a 9.7±1.1 16.2±3.8 9.7±1.1 0 GSH-OEt 113 76.5±6.5 65.6±5.7 26.2±9.0ab 8.1±4.3 19.5±2.6 13.7±3.0 1.1±1.1 VIT 71 60.0±5.6 54.8±7.8 32.7±10.8b 12.4±1.4 34.4±8.7 10.7±6.4 0 GSH-OEt VIT 53 57.4±10.7 58.5±8.8 31.1±9.3ab 10.4±5.8 34.8±5.6 6.7±6.7 0 a,bDifferent superscripts indicate significant differences (P&lt;0.05). *Percentage referred to the total number of oocytes at MII. This work was supported by MCIU, Spain (AGL2016-79802-P) and Generalitat de Catalunya (García-Martínez, 2017_FI_00451).

Composition of marsupial zona pellucida: a molecular and phylogenetic approach

The zona pellucida (ZP) is an extracellular matrix that surrounds mammalian oocytes. In eutherians it is formed from three or four proteins (ZP1, ZP2, ZP3, ZP4). In the few marsupials that have been studied, however, only three of these have been characterised (ZP2, ZP3, ZP4). Nevertheless, the composition in marsupials may be more complex, since a duplication of the ZP3 gene was recently described in one species. The aim of this work was to elucidate the ZP composition in marsupials and relate it to the evolution of the ZP gene family. For that, an in silico and molecular analysis was undertaken, focusing on two South American species (gray short-tailed opossum and common opossum) and five Australian species (brushtail possum, koala, Bennett's wallaby, Tammar wallaby and Tasmanian devil). This analysis identified the presence of ZP1 mRNA and mRNA from two or three paralogues of ZP3 in marsupials. Furthermore, evidence for ZP1 and ZP4 pseudogenes in the South American subfamily Didelphinae and for ZP3 pseudogenes in two marsupials is provided. In conclusion, two different composition models are proposed for marsupials: a model with four proteins (ZP1, ZP2 and ZP3 (two copies)) for the South American species and a model with six proteins (ZP1, ZP2, ZP3 (three copies) and ZP4) for the Australasian species.

151 Effect of season on the in vitro fertilizing ability of frozen - thawed bovine spermatozoa

Previous research indicated that the season during which oocytes are harvested affects quality of in vitro-produced embryos (Gupta et al. 2016 Anim. Reprod. Sci. 164, 162). In our own studies, sperm kinematics, membrane integrity, acrosome status, mitochondrial potential and reactive oxygen species were affected by season of semen collection (Sabés-Alsina et al. 2017 Vet. Rec. 180, 251). The aim of this study was to investigate effect of season of semen collection on in vitro fertilizing ability and embryo development of the same sperm samples from the sperm quality study, using lower than normal sperm doses to detect small differences between groups (Ward et al. 2003 Theriogenology 59, 1575). Frozen semen was available from 8 Holstein bulls kept outdoors in northern Spain, collected during winter, spring and summer. Bovine ovaries, Holstein and Swedish Red breeds, were obtained from an abattoir in spring. Oocytes were matured and fertilized in vitro with a low dose of frozen-thawed sperm (sperm:oocyte ratio 2500:1). After fertilization, presumptive embryos were evaluated at 44h for cleavage and on Day 8 for blastocyst development. Number of sperm binding to the zona pellucida and number of nuclei in developing blastocysts were assessed after staining with Hoechst 33342. There were 2 or 3 replicates per bull. For 555 oocytes inseminated, cleavage rates for winter, spring and summer semen collections were 42, 49 and 47%, respectively; blastocyst rates were 7, 12 and 8%; blastocyst cell numbers were 8.7, 10.2 and 7.8; and mean number of sperm bound was 0.70, 0.63 and 0.50. Although there were no differences (P&gt;0.05) due to season of semen collection for any of these end points, individual bulls had considerable variation in cleavage rate. In conclusion, despite previously published differences in sperm quality with season from these bulls, ability of frozen-thawed sperm to fertilize bovine oocytes and initial embryo development in vitro were not affected by season of semen collection, at least for oocytes collected in spring. However, bull-to-bull variation in cleavage rate was high. The authors gratefully acknowledge the financial support of the Ministerio de Economía y Competitividad and FEDER (AGL2016-79802-P). M. Sabes-Alsina was supported by a PIF from the Universitat Autònoma de Barcelona and by the STS of the Epiconcept COST Action; J. M. Morrell was funded by the Swedish Research Council for the environment, agricultural sciences and spatial planning (FORMAS; 221-2010-1241) and the Swedish Farmers’ Association (SLF; 1330039).

Porcine circovirus 3 is highly prevalent in serum and tissues and may persistently infect wild boar (Sus scrofa scrofa)

Porcine circovirus 3 (PCV-3) prevalence has been minimally investigated in wild boar; dynamics of infection and viral tissue distribution are currently unknown. In this study, serum samples from 518 wild boar (from years 2004 to 2018) were used to study frequency of infection. Also, serum samples from 19 boar captured and recaptured at least two times for a period of time from 1 month to 1 year were collected to determine PCV-3 infection dynamics. Finally, to elucidate PCV-3 DNA organic distribution, sera, different tissues and faeces were obtained from 35 additional wild boar. PCV-3 DNA was extracted and amplified with a conventional PCR. For the PCV-3 PCR-positive sera from the longitudinally sampled and different tissue types, a quantitative PCR was performed. Genome sequence was obtained from a number of PCV-3 PCR-positive samples from different years, different time-points of infection and tissues. Obtained results confirmed the susceptibility of wild boar to the virus, showing high frequency of PCV-3 detection (221 out of 518, 42.66%) and demonstrating circulation at least since 2004. Compiled data indicate the possibility of long-term infections, since 5 out of 10 PCV-3 PCR-positive boars longitudinally sampled showed positivity in samplings separated for more than 5 months. All tested tissue types' harboured PCV-3 genome, with the highest percentage of PCR positivity in submandibular lymph node, tonsil, lung, liver, spleen and kidney. The amount of DNA in all tested PCV-3 PCR-positive samples was moderate to low. All partial and complete PCV-3 sequences obtained from wild boar displayed high nucleotide identity, higher than 98%. In conclusion, this study further confirms that wild boar is susceptible to PCV-3 infection, showing high frequency of detection in this animal species. Furthermore, PCV-3 can be found in different tissues of wild boar and is apparently able to cause persistent infection.

40 Gene Expression Profiling of In Vitro-Produced Blastocysts Derived from In Vitro-Matured Bovine Oocytes Vitrified/Warmed in Media Supplemented with a Biopolymer Produced by an Antarctic Bacterium

Previous reports have demonstrated the beneficial effect of antifreeze glycoprotein supplementation during oocyte vitrification on preventing ice crystal formation and thus enhancing developmental competence after vitrification-warming. Pseudomonas sp. ID1, a bacterium isolated from marine sediment from Antarctica, produces an exopolysaccharide, M1 EPS, as a cold adaptation mechanism. Despite numerous studies on structural and morphological damages induced by cryopreservation in oocytes, few studies have focused on the impact of vitrification on the expression pattern of genes during early embryo development. In the present study, the expression patterns of 6 genes (BAX, BCL2-like 1, DNMT3A, UBE2A, SCLC2A3, and HDAC1) were investigated in Day 8 blastocysts resulting from in vitro-matured oocytes vitrified/warmed in media supplemented with various concentrations of M1 EPS. After 21 h of IVM, 1,062 oocytes were vitrified/warmed in media supplemented with 0, 0.001, 0.01, 0.1, and 1 mg mL−1 M1 EPS. At 24 h of IVM, oocytes were in vitro fertilized and in vitro cultured and the resulting blastocysts were harvested at Day 8 for RNA extraction and qPCR analysis. Fresh, non-vitrified oocytes were used as a control. Analysis of gene expression was performed through Kruskall-Wallis test and followed by Mann-Whitney test, and the level of significance was set at P ≤ 0.05. No significant differences were detected in relative mRNA abundance for SLC2A3, UBE2A, or HDAC-1 between blastocysts derived from vitrified oocytes, regardless of M1 EPS treatment. Expression of DNMT3A was significantly higher in embryos obtained from oocytes vitrified and warmed with 0.1 mg mL−1 M1 EPS compared with other treatment groups. However, no differences in DNMT3A expression were observed when the other vitrified groups were compared. The relative abundance of BAX transcript in embryos from oocytes vitrified in media supplemented with 0.1 mg mL−1 M1 EPS was higher than that in 0 or 0.001 mg mL−1 groups. Embryos from 0.01 and 0.1 mg mL−1 groups showed higher BCL2-like 1 mRNA abundance than those from the 0, 0.001, and 1 mg mL−1 groups. Whereas blastocysts from oocytes vitrified with 0.01 mg mL−1 M1 EPS exhibited the lowest BAX:BCL2-like 1 ratio, no significant differences in BAX:BCL2-like 1 ratio were observed between the other treatments. The significantly lower BAX:BCL2 ratio observed in blastocysts obtained from oocytes vitrified with 0.01 mg mL−1 M1 EPS could be indicative for a better embryo quality. Although optimizing the use of M1 EPS may benefit oocyte cryopreservation protocols, further research is required to clarify the exact mechanism through which it exerts its protective role. This study was supported by the Spanish Ministry of Science and Innovation (Project AGL2016-79802-P and grant CTQ2014-59632-R).

Rapid Prototyping of a Cyclic Olefin Copolymer Microfluidic Device for Automated Oocyte Culturing

Assisted reproductive technology (ART) can benefit from the features of microfluidic technologies, such as the automation of time-consuming labor-intensive procedures, the possibility to mimic in vivo environments, and the miniaturization of the required equipment. To date, most of the proposed approaches are based on polydimethylsiloxane (PDMS) as platform substrate material due to its widespread use in academia, despite certain disadvantages, such as the elevated cost of mass production. Herein, we present a rapid fabrication process for a cyclic olefin copolymer (COC) monolithic microfluidic device combining hot embossing—using a low-temperature cofired ceramic (LTCC) master—and micromilling. The microfluidic device was suitable for trapping and maturation of bovine oocytes, which were further studied to determine their ability to be fertilized. Furthermore, another COC microfluidic device was fabricated to store sperm and assess its quality parameters over time. The study herein presented demonstrates a good biocompatibility of the COC when working with gametes, and it exhibits certain advantages, such as the nonabsorption of small molecules, gas impermeability, and low fabrication costs, all at the prototyping and mass production scale, thus taking a step further toward fully automated microfluidic devices in ART.

Rapid Prototyping of a Cyclic Olefin Copolymer Microfluidic Device for Automated Oocyte Culturing

Assisted reproductive technology (ART) can benefit from the features of microfluidic technologies, such as the automation of time-consuming labor-intensive procedures, the possibility to mimic in vivo environments, and the miniaturization of the required equipment. To date, most of the proposed approaches are based on polydimethylsiloxane (PDMS) as platform substrate material due to its widespread use in academia, despite certain disadvantages, such as the elevated cost of mass production. Herein, we present a rapid fabrication process for a cyclic olefin copolymer (COC) monolithic microfluidic device combining hot embossing-using a low-temperature cofired ceramic (LTCC) master-and micromilling. The microfluidic device was suitable for trapping and maturation of bovine oocytes, which were further studied to determine their ability to be fertilized. Furthermore, another COC microfluidic device was fabricated to store sperm and assess its quality parameters over time. The study herein presented demonstrates a good biocompatibility of the COC when working with gametes, and it exhibits certain advantages, such as the nonabsorption of small molecules, gas impermeability, and low fabrication costs, all at the prototyping and mass production scale, thus taking a step further toward fully automated microfluidic devices in ART.

Daily exposure to summer temperatures affects the motile subpopulation structure of epididymal sperm cells but not male fertility in an in vivo rabbit model

High temperatures have negative effects on sperm quality leading to temporary or permanent sterility. The aim of the study was to assess the effect of long exposure to summer circadian heat stress cycles on sperm parameters and the motile subpopulation structure of epididymal sperm cells from rabbit bucks. Twelve White New Zealand rabbit bucks were exposed to a daily constant temperature of the thermoneutral zone (from 18 °C to 22 °C; control group) or exposed to a summer circadian heat stress cycles (30 °C, 3 h/day; heat stress group). Spermatozoa were flushed from the epididymis and assessed for sperm quality parameters at recovery. Sperm total motility and progressivity were negatively affected by high temperatures (P < 0.05), as were also specific motility parameters (curvilinear velocity, linear velocity, mean velocity, straightness coefficient, linearity coefficient, wobble coefficient, and frequency of head displacement; P < 0.05, but not the mean amplitude of lateral head displacement). Heat stress significantly increased the percentage of less-motile sperm subpopulations, although the percentage of the high-motile subpopulation was maintained, which is consistent with the fact that no effect was detected on fertility rates. However, prolificacy was reduced in females submitted to heat stress when inseminated by control bucks. In conclusion, our results suggest that environmental high temperatures are linked to changes in the proportion of motile sperm subpopulations of the epididymis, although fertility is still preserved despite the detrimental effects of heat stress. On the other hand, prolificacy seems to be affected by the negative effects of high temperatures, especially by altering female reproduction.

Effect of high temperatures on breeding rabbit behaviour

The present work is focussed on the behavioural response of rabbits (Oryctolagus cuniculus) housed in typical commercial conditions subjected to two different environmental temperature circadian cycles: one below the combination of temperature and humidity that is considered as stressful for rabbits, and the other with some hours a day subjected to moderately stressful temperatures. During the experiment, a total of 55 commercial breeding hybrid rabbits were housed in each room (43 nulliparous does and 12 bucks). Of these, 10 females (six 105 days old and four 80 days old) and 6 males (180 days old) were studied for 12 days, 12 h a day using video cameras to later scan sample for behaviour at 5-min intervals. Rabbits were divided into two rooms. Five females and three males were housed at 18.4°C mean temperature (Room A). The other five females and three males were housed at 20.1°C for 17 h a day, and at a temperature humidity index from 23.6 to 28.2 for the remaining 7 h (Room B). Posture (lying, sitting, prostrated or moving) and behaviour (grooming, exploring, resting, feeding and drinking) were assessed. Faecal cortisol metabolites (FCM) were also analysed, once before and after the behavioural study, from seven samples in each room. Statistical analyses were performed using the GENMOD procedure in SAS. No differences were found between rooms in FCM during the behaviour assessment. However, the presence of resting behaviour and prostration was higher (P < 0.05) in Room B than Room A and the opposite (P < 0.05) was observed for lying, sitting and exploring. In the case of grooming, a compensatory effect was observed in Room B, as rabbits reduced this activity in the warmest period of the day but increased it just before and after this period, which was not seen in Room A. It is concluded that behavioural changes can be observed in does and bucks subjected to moderately stressful thermal conditions before those changes can be seen in faecal cortisol concentration.

Bovine oocytes show a higher tolerance to heat shock in the warm compared with the cold season of the year

Heat stress is especially harmful for bovine ovarian follicle development and oocyte competence. In this study, we assessed the effects of heat shock on oocyte maturation in oocytes collected during the cold (February-March; n = 114) or warm (May-June; n = 116) periods of the year. In both cases, cumulus-oocyte complexes were matured under control (38 °C) and heat shock conditions (41.5 °C, 18-21 h of maturation). For each oocyte, nuclear stage, cortical granule distribution and steroidogenic activity of cumulus cells were evaluated. Based on the odds ratio, heat-shocked oocytes were 26.83 times more likely to show an anomalous metaphase II morphology. When matured under heat shock conditions, oocytes obtained in both seasons were similarly affected in terms of nuclear maturation, whereas a seasonal effect was observed on cytoplasmic maturation. For oocytes collected during the cold season, the likelihood to show an anomalous maturation was 25.96 times higher when exposed to the heat treatment than when matured under control conditions. By contrast, oocytes collected during the warm season matured under control or heat shock did not show significant risk of showing an anomalous cytoplasmic maturation. Our findings indicate an increased rate of premature oocytes in response to heat shock as well as a higher tolerance to this stress of oocytes harvested in the warm season compared with those collected in the colder period.

Anatomicohistological characteristics of the female genital organs of the white-lipped peccary (Tayassu pecari) in the Peruvian Amazon

This study examined the anatomical and histological characteristics of the genital organs of the female white-lipped peccary in the wild in different reproductive stages, collected by rural hunters in the North-eastern Peruvian Amazon. Mean ovulation rate was 2.12 +/- 0.83 follicles and litter size was 1.78 +/- 0.41 embryos or fetuses per pregnant female, resulting in a low rate of reproductive wastage, averaging 0.33 +/- 0.66 (16.04%) oocytes or embryos per pregnancy. The ovulation rate and the anatomical performance of the uterus could limit the prolificacy of this species. Females in follicular phase showed follicular waves suggesting the synchronous growth of a cohort of follicles. Different uterine and vaginal epithelium features changed in accordance with the reproductive state of the female. Pregnant females and females in the luteal phase presented a significant proliferation of endometrial uterine glands, characterized by hyperplasia and branching of endometrial glands, and increase in the proportion of cervical epithelial cells with periodic acid-schiff (PAS)-positive granules compared with that in females in the follicular phase. Females in the follicular phase showed a more developed vaginal epithelium (in thickness and in layer composition) than females in the luteal phase and pregnant females.

Impact of breed and sex on porcine endocrine transcriptome: a bayesian biometrical analysis

Background

Transcriptome variability is due to genetic and environmental causes, much like any other complex phenotype. Ascertaining the transcriptome differences between individuals is an important step to understand how selection and genetic drift may affect gene expression. To that end, extant divergent livestock breeds offer an ideal genetic material.

Results

We have analyzed with microarrays five tissues from the endocrine axis (hypothalamus, adenohypophysis, thyroid gland, gonads and fat tissue) of 16 pigs from both sexes pertaining to four extreme breeds (Duroc, Large White, Iberian and a cross with SinoEuropean hybrid line). Using a Bayesian linear model approach, we observed that the largest breed variability corresponded to the male gonads, and was larger than at the remaining tissues, including ovaries. Measurement of sex hormones in peripheral blood at slaughter did not detect any breed-related differences. Not unexpectedly, the gonads were the tissue with the largest number of sex biased genes. There was a strong correlation between sex and breed bias expression, although the most breed biased genes were not the most sex biased genes. A combined analysis of connectivity and differential expression suggested three biological processes as being primarily different between breeds: spermatogenesis, muscle differentiation and several metabolic processes.

Conclusion

These results suggest that differences across breeds in gene expression of the male gonads are larger than in other endocrine tissues in the pig. Nevertheless, the strong presence of breed biased genes in the male gonads cannot be explained solely by changes in spermatogenesis nor by differences in the reproductive tract development.

Transcriptome architecture across tissues in the pig

Background

Artificial selection has resulted in animal breeds with extreme phenotypes. As an organism is made up of many different tissues and organs, each with its own genetic programme, it is pertinent to ask: How relevant is tissue in terms of total transcriptome variability? Which are the genes most distinctly expressed between tissues? Does breed or sex equally affect the transcriptome across tissues?

Results

In order to gain insight on these issues, we conducted microarray expression profiling of 16 different tissues from four animals of two extreme pig breeds, Large White and Iberian, two males and two females. Mixed model analysis and neighbor – joining trees showed that tissues with similar developmental origin clustered closer than those with different embryonic origins. Often a sound biological interpretation was possible for overrepresented gene ontology categories within differentially expressed genes between groups of tissues. For instance, an excess of nervous system or muscle development genes were found among tissues of ectoderm or mesoderm origins, respectively. Tissue accounted for ~11 times more variability than sex or breed. Nevertheless, we were able to confidently identify genes with differential expression across tissues between breeds (33 genes) and between sexes (19 genes). The genes primarily affected by sex were overall different than those affected by breed or tissue. Interaction with tissue can be important for differentially expressed genes between breeds but not so much for genes whose expression differ between sexes.

Conclusion

Embryonic development leaves an enduring footprint on the transcriptome. The interaction in gene × tissue for differentially expressed genes between breeds suggests that animal breeding has targeted differentially each tissue's transcriptome.

Reproductive performance of captive collared peccaries (Tayassu tajacu) in the eastern Amazon

This study analyses reproductive parameters resulting from 74 parturitions in a population of captive collared peccaries in the eastern Amazon (Belém, State of Pará, Brazil) during a 65-month survey. Parturitions were homogeneously distributed throughout the year. The average litter size was 1.85 newborns per parturition. Collared peccary females had a newborn sex ratio of 52.6% females and 47.4% males. The mean age at first parturition was 639, although, the earliest first parturition occurred at age of 381 days. Estimated parturition-conception interval was 58 days. Mean farrowing interval was 196 days and mean production was 1.03 litters and 1.86 newborns per year per female. Mortality rate in newborns less than 2 months old was 26.9% of the total newborn population. Most identified causes of death were abandonment by the mother (22.2%) and trauma due to aggression (13.9%). Newborn deaths occurred mainly during the first two days of life. This study suggests that the collared peccary possesses interesting reproductive parameters for its introduction in captive breeding programmes in the Amazon region.

Climate factors affecting conception rate of high producing dairy cows in northeastern Spain

Summer heat stress is a main factor related to low conception rate in high producing dairy herds in warm areas worldwide. We assessed the impact of several climate variables on conception rate in high producing dairy cows in northeastern Spain by examining 10,964 inseminations. The temperature-humidity index (THI) was compared with maximum temperature in terms of its efficiency at predicting conception rate. The following data were recorded for each animal: herd, lactation number, insemination number, insemination date, inseminating bull, and AI technician along with climate variables such as mean and maximum temperatures, rainfall, mean and maximum THI for individual time points Days 7 to 1 before insemination, the day of insemination and 1, 2 and 3 days after insemination. Averages were also established for the following periods: from 7 days before insemination to the insemination day, from 3 days before insemination to the insemination day and from the insemination day to 3 days postinsemination. Based on the odds ratios, the likelihood of conception rate increased significantly by factors of 1.48, 1.47, 1.5, and 1.1 for the respective maximum THI classes <70, 71-75, 76-80, and 81-85 only on Day 3 before AI, while on the insemination day, it increased by factors of 1.73, 1.53, 1.11, and 1.3 for the respective maximum THI classes <70, 71-75, 76-80, and 81-85. In a subsequent logistic regression excluding mean and maximum THI, the effectiveness of temperature at predicting conception rate was evaluated. Although high, the fit of the second logistic regression model was slightly lower than that of the full model (P=0.88 versus P=0.98, respectively) and the information provided by the THI model. The likelihood of conception rate increased significantly by factors of 1.5, 1.2, 1.0, 1.0 for the respective maximum temperature classes <20, 21-25, 26-30, 31-35 degrees C on Day 1 after AI. The choice of the THI or temperature to monitor the farm environment would have to depend on the particular farm and situation. In our study conditions, the use of maximum temperature alone gives a new point of view regarding the information provided by the THI variables.

Factors affecting the fertility of high producing dairy herds in northeastern Spain

Infertility has been often correlated to a rising milk yield in high producing dairy cattle. The aim of the present study was to evaluate, using logistic regression procedures, the effects of several management indicators on the fertility of four dairy herds in northeastern Spain. Data derived from 10,965 artificial insemination (AI). The factors examined were: herd, milking frequency (three versus two milkings per day), lactation number, previous twinning and disorders such as placenta retention and pyometra, milk production at AI, the inseminating bull, season (warm versus cool period) and year effects, AI technician and repeat breeding syndrome (cows undergoing four or more AI). Our findings indicated no effects on fertility of the herd, year of AI, previous twining, placenta retention and pyometra and milk production at AI. Based on the odds ratios, the likelihood of pregnancy decreased: in cows milked three times per day (by a factor of 0.62); for each one unit increase in lactation number (by a factor of 0.92); for inseminations performed during the warm period (by a factor of 0.67); in repeat breeder cows (by a factor of 0.73); and when 3 of the 45 inseminating bulls included in the study were used (by factors of 0.35, 0.43 and 0.44, respectively). Of the 13 AI technicians participating in the study, 3 were related to a fertility rate improved by odds ratios of 1.86, 1.84 and 1.30, respectively, whereas 2 technicians gave rise to fertility rates reduced by odds ratios of 0.64 and 0.49, respectively. Under our study conditions, management practices were able to compensate for the effects of previous twining and reproductive disorders such as placenta retention and pyometra. However, fertility was significantly affected by the factors milking frequency, AI technician, inseminating bull, repeat breeding syndrome, lactation number and AI season.

A health evaluation in a colony of captive collared peccaries (Tayassu tajacu) in the eastern Amazon

This study pretends to determine baseline data on the health and mortality of a colony of captive collared peccaries in the Eastern Amazon (Belém, State of Pará, Brazil) during a 65-months survey. Thirty-nine out of 166 animals (23.5%) died and were examined post-mortem. Monthly mortality averaged 1.2%. The highest mortality rate was observed in newborns (74.4%). Abandonment by the mother and aggression were responsible for 24.1% and 13.8% of the total newborn deaths, respectively. Most frequent causes of non-neonatal death were food poisoning (50.0%) due to an episode of accidental bitter cassava leaves ingestion and traumatism due to aggressions between animals (10.0%). Results from serology for different infectious diseases showed that 4.9% (2/41) collared peccaries had antibodies against Brucella spp. and 9.8% (4/41) animals had antibodies to two different Leptospira spp. serovars, butembo and autumnalis. This is the first survey of morbidity and mortality in captive collared peccaries in the Amazon region.

Screening for high fertility in high-producing dairy cows

A retrospective study involving 2756 pregnancies from two commercial dairy herds in northeastern Spain determined relationships between management, production and reproductive data, and high fertility (conception before 90 days in milk) in high-producing dairy cows. High fertility was registered in 989 (35.9%) cows. The following data were recorded for each animal: herd, repeated animal (cows included two or more times within the study in which data were obtained from different lactational periods), parity (primiparous versus multiparous), previous twinning, reproductive disorders following calving (retained placenta, primary metritis) and at postpartum gynecological examination (incomplete uterine involution, pyometra and ovarian cysts), days in milk at conception, previous estrous synchronization and season of calving and conception. In order to evaluate the possible effect of high production during the peak milk yield on subsequent fertility, daily milk production at Day 50 postpartum was also recorded and cows were classified as high (> or = 50 kg) and low (< 50 kg) producers. Logistic regression analysis indicated no significant effects of herd, repeated animal, previous twinning, reproductive disorders such as primary metritis, incomplete uterine involution, pyometra and ovarian cysts, previous estrous synchronization and season of calving and insemination. Based on the odds ratio, the likelihood of high fertility increased in high-producer cows by a factor of 6.8. High fertility was less likely for multiparous cows (by a factor of 0.35) and for cows suffering placenta retention (by a factor of 0.65). High fertile cows produced a mean of 49.5 kg milk at Day 50 postpartum, in contrast to that 43.2 kg milk of the remainder cows. These findings question the negative effect of high production on fertility. Our results indicated that high individual cow milk production can be positively related to high fertility.

Relationship between heat stress during the peri-implantation period and early fetal loss in dairy cattle

The aim of the present study was to establish whether temperature-humidity index values, as a measure of heat comfort, from Days 1 to 40 of gestation could be associated with the pregnancy loss rate in high producing dairy cows. Data from 1391 pregnancies were recorded. Pregnancy was diagnosed by transrectal ultrasonography between Days 34 and 45, and again 90 days after insemination. Pregnancy loss was assumed when the second pregnancy diagnosis on Day 90 proved negative and was registered in 7.8% (108/1391) of pregnancies. Mean and maximum temperature-humidity index values were established for each cow for Days 0 (day of insemination), 1, 2 and 3 after insemination, and averages established for Days 0-3, 0-10, 11-20, 21-30 and 31-40 after insemination. Cow and management variables previously found to be significantly correlated with the early fetal loss in the same geographical area were also recorded. The relative contribution of each factor to the probability of pregnancy loss was determined using logistic regression models. Based on the odds ratio, a strong association with pregnancy loss of the factors warm period of pregnancy (warm period-May to September versus cool-October to April), twin pregnancy (as negative factors: odds ratios 3.1 and 3.4, respectively) and an additional corpus luteum (as a positive factor: odds ratio 0.32) was confirmed. The likelihood of pregnancy loss increased by a factor of 1.05 for each additional unit of the mean maximum temperature-humidity index from Days 21 to 30 of gestation. Logistic regression analysis revealed no significant effects of temperature-humidity index values for the remaining gestation periods. Our results indicate that heat stress can compromise the success of gestation during the peri-implantation period, such that high temperature-humidity index values for the period 21-30 days of gestation are a risk factor for subsequent early fetal loss.

Relationship between rainfall and Neospora caninum-associated abortion in two dairy herds in a dry environment

The possible direct relationship between climate variations and abortion in Neospora caninum-infected cows has not been studied. The objective of this study was to determine whether climate changes could be a risk factor for abortion in N. caninum-infected cows, and was based on yearly serological screening for neosporosis and on the confirmation of N. caninum infection on aborted fetuses in two high-producing dairy herds with a mean 27% seroprevalence of N. caninum antibodies. The final population study was comprised of 357 pregnancies in seropositive animals. Logistic regression analysis indicated no significant effects of herd, N. caninum antibody titre, climate variables during the first and third trimesters of gestation, mean and maximum temperature-humidity index values during the second trimester of gestation, and previous abortion on the abortion rate. Based on the odds ratio, a 1-unit increase in lactation number yielded a 0.85-fold decrease in the abortion rate. The likelihood of abortion was 1.9 times (1/0.54) lower for pregnant cows inseminated with beef bull semen compared with Holstein-Friesian bull semen. The likelihood of abortion decreased significant and progressively by factors of 0.5, 0.41 and 0.3 for the respective classes 40-49, 30-39 and <30 rainfall mm during the second trimester of gestation (using the class >or=60 rainfall mm as reference). As a general conclusion, it seems that increased rainfall in a dry environment can compromise the success of gestation in N. caninum-infected cows. Attempts should therefore be made to reduce environment effects during the second trimester of gestation, a period in which the immune response of cows is diminished.

Distribution of prepubertal and adult goat oocyte cortical granules during meiotic maturation and fertilisation: ultrastructural and cytochemical study

The aim of this study was evaluate cortical granule (CG) distribution during in vitro maturation (IVM) and fertilisation of prepubertal goat oocytes compared to CG distribution of ovulated and in vitro fertilised oocytes from adult goats. Oocytes from prepubertal goats were recovered from a slaughterhouse and were matured in M199 with hormones and serum for 27 hr. Ovulated oocytes were collected from gonadotrophin treated Murciana goats. Frozen-thawed spermatozoa were selected by centrifugation in percoll gradient and were capacitated in DMH with 20% steer serum for 1 hr. Ovulated and IVM-oocytes were inseminated in DMH medium with steer serum and calcium lactate for 20 hr. Oocytes and presumptive zygotes were stained with FITC-LCA (Lens culinaris agglutinin labelled with fluorescein isothiocyanate) and observed under a confocal laser scanning microscope. Ultrastructure morphology of oocytes and presumptive zygotes were analysed by transmission electron microscopy (TEM). Prepubertal goat oocytes at germinal vesicle stage show a homogeneous CG distribution in the cytoplasm. IVM-oocytes at Metaphase II (MII) and ovulated oocytes presented CGs located in the cortex with the formation of a monolayer beneath to the plasma membrane. At 20 hr postinsemination (hpi), zygotes from IVM-oocytes showed a complete CG exocytosis whereas zygotes from ovulated oocytes presented aggregates of CGs located at the cortical region. Images by TEM detected that CGs were more electrodense and compacts in oocytes from prepubertal than from adult goats.