Magnetic-Assisted Control of Eggs and Embryos via Zona Pellucida-Linked Nanoparticles

Eggs and embryo manipulation is an important biotechnological challenge to enable positioning, entrapment, and selection of reproductive cells to advance into a new era of nature-like assisted reproductive technologies. Oviductin (OVGP1) is an abundant protein in the oviduct that binds reversibly to the zona pellucida, an extracellular matrix that surrounds eggs and embryos. Here, the study reports a new method coupling OVGP1 to magnetic nanoparticles (NP) forming a complex (NPOv). NPOv specifically surrounds eggs and embryos in a reversible manner. Eggs/embryos bound to NPOv can be moved or retained when subjected to a magnetic force, and interestingly only mature-competent eggs are attracted. This procedure is compatible with normal development following gametes function, in vitro fertilization, embryo development and resulting in the birth of healthy offspring. The results provide in vitro proof-of-concept that eggs and embryos can be precisely guided in the absence of physical contact by the use of magnets.

Proteomic Insights into Seminal Plasma and Spermatozoa Proteins of Small-Spotted Catsharks, Scyliorhinus canicula: Implications for Reproductive Conservation in Aquariums

In the ex situ conservation of chondrichthyan species, successful reproduction in aquaria is essential. However, these species often exhibit reduced reproductive success under human care. A key aspect is that conventional sperm analyses do not provide insights into the functional competence of sperm. However, proteomics analysis enables a better understanding of male physiology, gaining relevance as a powerful tool for discovering protein biomarkers related to fertility. The present work aims to build the first proteome database for shark semen and to investigate the proteomic profiles of seminal plasma and spermatozoa from small-spotted catsharks (Scyliorhinus canicula) related to the underlying adaptations to both natural and aquarium environments, thereby identifying the reproductive impact in aquarium specimens. A total of 305 seminal plasma and 535 spermatozoa proteins were identified. Among these, 89 proteins (29.2% of the seminal plasma set) were common to both spermatozoa and seminal plasma. In the seminal plasma, only adenosylhomocysteinase protein showed differential abundance (DAP) between wild and aquarium animals. With respect to the spermatozoa proteins, a total of 107 DAPs were found between groups. Gene Ontology enrichment analysis highlighted the primary functional roles of these DAPs involved in oxidoreductase activity. Additionally, KEGG analysis indicated that these DAPs were primarily associated with metabolic pathways and carbon metabolism. In conclusion, we have successfully generated an initial proteome database for S. canicula seminal plasma and spermatozoa. Furthermore, we have identified protein variations, predominantly within spermatozoa, between aquarium and wild populations of S. canicula. These findings provide a foundation for future biomarker discovery in shark reproduction studies. However, additional research is required to determine whether these protein variations correlate with reproductive declines in captive sharks.

Modulation of Caecal Microbiota and Metabolome Profile in Salmonella-Infected Broilers by Phage Therapy

Bacteriophage therapy is considered one of the most promising tools to control zoonotic bacteria, such as Salmonella, in broiler production. Phages exhibit high specificity for their targeted bacterial hosts, causing minimal disruption to the niche microbiota. However, data on the gut environment's response to phage therapy in poultry are limited. This study investigated the influence of Salmonella phage on host physiology through caecal microbiota and metabolome modulation using high-throughput 16S rRNA gene sequencing and an untargeted metabolomics approach. We employed 24 caecum content samples and 24 blood serum samples from 4-, 5- and 6-week-old broilers from a previous study where Salmonella phages were administered via feed in Salmonella-infected broilers, which were individually weighed weekly. Phage therapy did not affect the alpha or beta diversity of the microbiota. Specifically, we observed changes in the relative abundance of 14 out of the 110 genera using the PLS-DA and Bayes approaches. On the other hand, we noted changes in the caecal metabolites (63 up-accumulated and 37 down-accumulated out of the 1113 caecal metabolites). Nevertheless, the minimal changes in blood serum suggest a non-significant physiological response. The application of Salmonella phages under production conditions modulates the caecal microbiome and metabolome profiles in broilers without impacting the host physiology in terms of growth performance.

Zoonotic Parasites in Playgrounds in Southern Spain: A One Health Approach

Zoonotic parasitic diseases are considered a global threat to public health. In this sense, canines and felines may be infected by different cosmopolitan parasites, with playgrounds serving as an important focus of infection for humans, as well as domestic or wild animals. Knowledge of the epidemiological situation of parasites in animal reservoirs integrated into the environment, identifying the spread pathways, is a key element for an effective response to this threat. Thus, the aim of this study was to assess the frequency of intestinal parasites with zoonotic potential in 120 playgrounds in the Malaga province (Spain). Samples were processed and analysed following standard parasitological procedures. Some 36.7% of playgrounds were parasite-positive with one or more zoonotic parasites. The most common parasites recovered were nematodes (60.0%), followed by protozoan species (33.3%) and cestodes (6.7%). In the parasite-positive playgrounds, Toxocara spp. (17.0 ± 3.5%) and Giardia duodenalis (17.0 ± 3.4%) were the most predominant parasites. In addition, 34.1% of playgrounds were infected with multiple parasites. Our results show a high presence of parasitic forms with zoonotic potential in playgrounds in Malaga, Spain. Due to the close contact between pets and humans in playgrounds, the potential zoonotic risk may increase if prevention and control measures are not designed.

A 3D-Printed Large Holding Capacity Device for Minimum Volume Cooling Vitrification of Embryos in Prolific Livestock Species

Although many devices have been developed to reduce sample volume, with an explosion of methods appearing in the literature over the last decade, commercially available devices with simultaneous vitrification of a larger number of embryos are scarce, with the apparent gap for their use in prolific livestock species. In this study, we investigated the effectiveness of a new three-dimensional (3D)-printed device that combines minimum volume cooling vitrification with simultaneous vitrification of a larger number of rabbit embryos. Late morulae/early blastocysts were vitrified with the open Cryoeyelet^® device (n = 175; 25 embryos per device), the open Cryotop^® device (n = 175; 10 embryos per device), and the traditional closed French mini-straw device (n = 125; 25 embryos per straw) and compared in terms of in vitro development and reproductive performance after transfer to adoptive mothers. Fresh embryos constituted the control group (n = 125). In experiment 1, there was no difference in the development rate to the blastocyst hatching stage between the CryoEyelet^® and the other devices. In experiment 2, the CryoEyelet^® device showed a higher implantation rate compared with the Cryotop^® (6.3% unit of SD, p = 0.87) and French mini-straw^® (16.8% unit of SD, p = 1.00) devices. In terms of offspring rate, the CryoEyelet^® device was similar to the Cryotop^® device but superior to the French straw device. Regarding embryonic and fetal losses, the CryoEyelet^® showed lower embryonic losses compared to other vitrification devices. The analysis of bodyweight showed that all devices showed a similar outcomes-a higher birthweight but a lower body weight at puberty than those in the fresh transfer embryos group. In summary, the CryoEyelet^® device can be used for the vitrification of many late morulae or early blastocyst stage rabbit embryos per device. Further studies should be performed to evaluate the CryoEyelet^® device in other polytocous species for the simultaneous vitrification of a large number of embryos.

Examining the effects of Salmonella phage on the caecal microbiota and metabolome features in Salmonella-free broilers

Bacteriophages selectively infect and kill their target bacterial host, being a promising approach to controlling zoonotic bacteria in poultry production. To ensure confidence in its use, fundamental questions of safety and toxicity monitoring of phage therapy should be raised. Due to its high specificity, a minimal impact on the gut ecology is expected; however, more in-depth research into key parameters that influence the success of phage interventions has been needed to reach a consensus on the impact of bacteriophage therapy in the gut. In this context, this study aimed to investigate the interaction of phages with animals; more specifically, we compared the caecum microbiome and metabolome after a Salmonella phage challenge in Salmonella-free broilers, evaluating the role of the phage administration route. To this end, we employed 45 caecum content samples from a previous study where Salmonella phages were administered via drinking water or feed for 24 h from 4, 5 to 6-weeks-old broilers. High-throughput 16S rRNA gene sequencing showed a high level of similarity (beta diversity) but revealed a significant change in alpha diversity between broilers with Salmonella-phage administered in the drinking water and control. Our results showed that the phages affected only a few genera of the microbiota's structure, regardless of the administration route. Among these, we found a significant increase in Streptococcus and Sellimonas in the drinking water and Lactobacillus, Anaeroplasma and Clostridia_vadinBB60_group in the feed. Nevertheless, the LC-HRMS-based metabolomics analyses revealed that despite few genera were significantly affected, a substantial number of metabolites, especially in the phage administered in the drinking water were significantly altered (64 and 14 in the drinking water and feed groups, respectively). Overall, our study shows that preventive therapy with bacteriophages minimally alters the caecal microbiota but significantly impacts their metabolites, regardless of the route of administration.

Gut–Brain Axis: Insights from Hippocampal Neurogenesis and Brain Tumor Development in a Mouse Model of Experimental Colitis Induced by Dextran Sodium Sulfate

Chronic inflammatory bowel disorders (IBD) are idiopathic diseases associated with altered intestinal permeability, which in turn causes an exaggerated immune response to enteric antigens in a genetically susceptible host. A rise in psych cognitive disorders, such as anxiety and depression, has been observed in IBD patients. We here report investigations on a model of chemically induced experimental colitis by oral administration of sodium dextran sulfate (DSS) in C57BL/6 mice. We investigate, in vivo, the crosstalk between the intestine and the brain, evaluating the consequences of intestinal inflammation on neuroinflammation and hippocampal adult neurogenesis. By using different DSS administration strategies, we are able to induce acute or chronic colitis, simulating clinical characteristics observed in IBD patients. Body weight loss, colon shortening, alterations of the intestinal mucosa and fecal metabolic changes in amino acids-, lipid- and thiamine-related pathways are observed in colitis. The activation of inflammatory processes in the colon is confirmed by macrophage infiltration and increased expression of the proinflammatory cytokine and oxidative stress marker (Il-6 and iNOS). Interestingly, in the hippocampus of acutely DSS-treated mice, we report the upregulation of inflammatory-related genes (Il-6, Il-1β, S-100, Tgf-β and Smad-3), together with microgliosis. Chronic DSS treatment also resulted in neuroinflammation in the hippocampus, indicated by astrocyte activation. Evaluation of stage-specific neurogenesis markers reveals deficits in the dentate gyrus after acute and chronic DSS treatments, indicative of defective adult hippocampal neurogenesis. Finally, based on a possible causal relationship between gut-related inflammation and brain cancer, we investigate the impact of DSS-induced colitis on oncogenesis, using the Ptch1^+/−/C57BL/6 mice, a well-established medulloblastoma (MB) mouse model, finding no differences in MB development between untreated and DSS-treated mice. In conclusion, in our experimental model, the intestinal inflammation associated with acute and chronic colitis markedly influences brain homeostasis, impairing hippocampal neurogenesis but not MB oncogenesis.

P-248 Fallopian tube extracellular matrix hydrogels for in vitro embryo culture in rabbit models: A post-natal study

Study question

Can tissue-specific extracellular matrix (ECM) hydrogels derived from decellularized (DC) fallopian tubes have phenotypic consequences in the offspring when used for in vitro embryo culture?

Summary answer

Tissue-specific ECM hydrogels from DC rabbit fallopian tubes influence assisted reproductive technologies (ART) outcomes, resulting in offspring with a higher body weight.

What is known already

The in vitro culture of embryos fails to mimic the physiological dynamism occurring in the reproductive tract. In response to this sub-optimal environment, mammalian embryo exhibits a high degree of developmental plasticity, leading to specific phenotypic deviations at birth and beyond (e.g. low weight). Recently, it has been demonstrated that using in vivo derived culture complements, these changes can be ameliorated. The ECM is one of the elements shown to be important in retaining structural and biological signals from the native source tissue. The current bioengineering techniques could provide hydrogels mimicking the native environment and offering an optimal embryo development.

Study design, size, duration

This study was approved by an ethics committee (2018/VSC/PEA/0116). Rabbit oviducts (n = 24) were collected, fragmented, DC and solubilized to create hydrogels. After physicochemical characterization, the tissue-specific ECM hydrogels were used for in vitro culture of pronuclear embryos during 48 hours (n = 146), which were subsequently transferred to recipient females, along with embryos cultured under control conditions (n = 138). After delivery, the rabbits were weighed during 20 weeks and blood tests were performed at weeks 8 and 20.

Participants/materials, setting, methods

To create hydrogels, we employed a decellularization protocol based on SDS detergent. After characterizing and validating decellularization (Francés-Herrero et al. 2021), ECM hydrogels were used to generate coatings (overnight at 37ºC) on culture plates. Pronuclear embryos were cultured until morula stage and then transferred by laparoscopy to obtain the offspring. The animals were weighed and their blood was analyzed by hemogram. T-test was used for the statistical analysis after normality verification (p < 0.05 statistically significant).

Main results and the role of chance

After 48 hours of embryo culture, no differences in development and morphology were detected between the coating and control conditions (Francés-Herrero et al. 2021). With a total of 284 embryos transferred, the implantation and live birth rates were slightly higher in the coating group than in the control group (31.26 ± 21.44% vs 26.53 ± 24.8% and 19.96 ± 12.5% vs 18.68 ± 24.68%, respectively), but the differences were not statistically significant. During the first 20 weeks of life, the animals from the coating group consistently showed higher weights than the control group. Although this difference was not significant at birth (75.15 ± 15.48 g vs 61.88 ± 17.79 g, respectively), it was significant at subsequent measurements (1117.73 ± 172.54 g vs 942 ± 105.51 g at week 5, 2513 ± 352.83 g vs 2256.25 ± 168.52 g at week 10, 3475.56 ± 297.91 g vs 3257.5 ± 189.94 g; at week 15 and 4151.11 ± 269.28 g vs 3808.75 ± 293.08 g at week 20; p < 0.05). The animals of both experimental groups showed normal blood parameters (white blood cells, % lymphocytes, % monocytes, % granulocytes, red blood cells and hematocrit) at 8 and 20 weeks of life.

Limitations, reasons for caution

This study has been carried out in an animal model and, although the offspring generated is healthy, the scope of this technique is still unknown. So, the next step would be to study the embryonic reprogramming or media metabolomic profile under ECM in vitro culture.

Wider implications of the findings

These findings show how culture media supplementation with fallopian tube ECM allows improving in vitro conditions and decreases postnatal phenotypic deviations after ART. This study could initiate a new embryo culture techniques era to guarantee that ART are utilized in the most efficient and safest possible practice.

Trial registration number

Not applicable

Effects of Rederivation by Embryo Vitrification on Performance in a Rabbit Paternal Line

Embryo cryopreservation is a valuable tool for maintaining genetic variability and preserving breeds and lines, allowing to assess the response to selection and enabling genetic diffusion. This study aimed to evaluate the impact of rederivation by embryo vitrification and transfer procedures on the growth and reproductive traits in a paternal rabbit line selected for average daily gain from weaning (28 days old) to fattening (63 days old). The rederived population was bred over two generations at the same time as a control population of this paternal line and, growth trait parameters (weights at weaning, end of the fattening period, and average daily gain) and reproductive performance (kindling rate, litter size at birth and at weaning) were compared with three filial generations. Moreover, fetal growth and litter size components were assessed for the second generation by ultrasonography and laparoscopy. Differences in postnatal growth traits (end of fattening weight and average daily gain) were observed in the three generations assessed. However, fetal growth, litter size components, and reproductive traits did not show significant differences. In conclusion, cryopreservation and embryo transfer processes cause changes in growth traits of reconstituted populations that influence the following generations, without changes in reproductive traits in a paternal line of rabbits.

Oocyte quality and in vivo embryo survival after ovarian stimulation in nulliparous and multiparous rabbit does

Superovulation treatments aim to stimulate multifollicular recruitment, maximizing the number of oocytes or transferable embryos produced. Factors associated with the superovulation protocol, female characteristics and many other factors are determinants in the number and quality of oocytes obtained. An accurate way to assess oocyte quality more precise than morphological appearance is genetic expression. The present study aims to compare the response of nulliparous and multiparous females to superovulatory stimulation, studying its effect on the expression of some genes associated with the activation, growth, development and oocyte-embryo transition of oocytes, as well as its impact on in vivo embryonic development and viability rate at birth. In a first experiment, the effect of stimulation treatment on the ovulation response and the expression of the MSY2, MATER, ITPR1, ITPR2, ITPR3, eIF4E, PAR1, PAPOL-A, PAPOL-G, ZAR1 and YY1 genes in nulliparous and multiparous females were determined. In a second experiment, the implantation and viability at birth of embryos from superovulated nulliparous and multiparous females were analysed. The ovulation rate was significantly higher in the superovulation groups than in the control groups. The ovulation rate was significantly increased in nulliparous females compared with multiparous does. From the eleven genes analysed, only the expression of MATER, PAPOL-A, PAPOL-G and ZAR-1 genes was shown to be different among experimental groups. Finally, in terms of implantation rate and viability at birth, the nulliparous control group showed better results than the rest of the groups. Both hyperstimulation treatment and reproductive female's history seem to alter the transcriptome of important genes related to oocyte maturation and competence acquisition, affecting in vivo embryo viability.

Early Embryo Exposure to Assisted Reproductive Manipulation Induced Subtle Changes in Liver Epigenetics with No Apparent Negative Health Consequences in Rabbit

Embryo manipulation is a requisite step in assisted reproductive technology (ART). Therefore, it is of great necessity to appraise the safety of ART and investigate the long-term effect, including lipid metabolism, on ART-conceived offspring. Augmenting our ART rabbit model to investigate lipid metabolic outcomes in offspring longitudinally, we detected variations in hepatic DNA methylation ART offspring in the F3 generation for embryonic exposure (multiple ovulation, vitrification and embryo transfer). Through adult liver metabolomics and proteomics, we identified changes mainly related to lipid metabolism (e.g., polyunsaturated fatty acids, steroids, steroid hormone). We also found that DNA methylation analysis was linked to changes in lipid metabolism and apoptosis genes. Nevertheless, these differences did not apparently alter the general health status. Thus, our findings suggest that ART is likely to be a player in embryo epigenetic events related to hepatic homeostasis alteration in adulthood.

Impact of embryo technologies on secondary sex ratio in rabbit

Increasing evidence indicates that assisted reproductive technologies (ARTs) disturb skewed sex-ratio and induce sex-dimorphic postnatal effects. Undoubtedly, the combination of multiple ovulation and embryo transfer (MOET) together with the use of vitrification technique (MOVET) is currently being used in breeding programs. However, since the first case of sex skewing reported in 1991, the accumulative and long-term transmission of skewed sex-ratio to future generations has not been thoroughly evaluated. Here we test as MOVET program induce a skewed sex ratio, and we consider skewed sex ratio transmission to future generations. To this end, we first evaluated the F1 generation, demonstrating that a MOVET program causes a severe imbalance skewed secondary sex ratio (SSR) towards male by 12%. This imbalanced persist after a second MOVET program (F2 generation), with an accumulative skewed SSR towards male by 25%. Finally, using a crossbred generation derived from crossing F1 males derived from a MOVET program with naturally-conceived (NC) females, we show that the imbalance skewed SRR persist. Bodyweight comparison between MOVET animals and NC counterparts revealed significant changes at birth, weaning and adulthood. However, there was a significant interaction between F2 MOVET animals and sex, demonstrating an apparent accumulative sex-dimorphic effect. At adulthood, MOVET derived males presented a lower body weight. In conclusion, we show that the MOVET program causes a direct, accumulative and long-term transmission of skewed SSR.

Roles of host genetics and sperm microbiota in reproductive success in healthy rabbit

Although the effects of sperm microbiota and sperm quality have been described previously, recent studies provide evidence that female genital modifications triggered by seminal components could be of significant importance to identify some disturbances associated with fertility. So, sperm microbiota could play a key role in sperm quality, contributing to fertilisation. To understand how sperm microbiota diversity is influenced by the host genetics, the symbiotic bacteria in four inbred lines raised in the same animal facility and their effects on sperm quality and fertility were analysed. Forty healthy rabbits from four selected Spanish commercial lines were used in this research (three based on litter performance, designated A, V and LP, and one selected for daily body weight gain, called R). Significant variations in the seminal concentration, morphology and some motion parameters were found among inbred lines, but sperm motility and viability were similar among inbred lines. After mating, inbred lines selected for litter size had the same fertility rate, significantly higher than inbred line selected for body weight (82 ± 3.3%, 79 ± 3.5% and 89 ± 4.5% versus 61 ± 3.7%, for the A, V and LP vs R lines, respectively, p < 0.05). Bacteria belonging to Proteobacteria, Firmicutes, Fusobacteria and Bacteroidetes were identified in sperm microbiota. At genus level, the bacterial community composition in the sperm microbiota was influenced by host genetics. A total of 35, 16, 34, and 51 genera were accurately detected in the A, V, LP, and R lines, respectively. Moreover, Enhydrobacter, Ferruginibacter, Myroides Paracoccus, Rheinheimera, Tepidiphilus, Tetradesmus obliquus and Thauera genera were present only in the inbred lines selected for litter size. Moreover, the discriminant analysis revealed Lysinibacillus and Flavobacterium genera as potential biomarkers for fertility. Thus, these two genera may play a key role in fertility. Our results demonstrated the existence of a rabbit inbred line-specific variation in bacterial occurrence in sperm microbiota. Moreover, fertility differentials among inbred lines that were not predicted by routine semen analysis could be partly explained by the symbiotic state of the semen microbiota.

Rederivation by Cryopreservation of a Paternal Line of Rabbits Suggests Exhaustion of Selection for Post-Weaning Daily Weight Gain after 37 Generations

Simple Summary

This study was conducted to evaluate the effect of a long-term selection for post-weaning daily weight gain after 37 generations, using vitrified embryos with 18 generational intervals to rederive two coetaneous populations, reducing or avoiding genetic drift, environmental and cryopreservation effects. This study reports that the selection programme had improved average daily weight gain without variations in adult body weight but, after 37 generations of selection, this trait seems exhausted.

Abstract

Rabbit selection programmes have mainly been evaluated using unselected or divergently selected populations, or populations rederived from cryopreserved embryos after a reduced number of generations. Nevertheless, unselected and divergent populations do not avoid genetic drift, while rederived animals seem to influence phenotypic traits such as birth and adult weights or prolificacy. The study aimed to evaluate the effect of a long-term selection for post-weaning average daily weight gain (ADG) over 37 generations with two rederived populations. Specifically, two coetaneous populations were derived from vitrified embryos with 18 generational intervals (R19 and R37), reducing or avoiding genetic drift and environmental and cryopreservation effects. After two generations of both rederived populations (R21 vs. R39 generations), all evaluated traits showed some progress as a result of the selection, the response being 0.113 g/day by generation. This response does not seem to affect the estimated Gompertz growth curve parameters in terms of the day, the weight at the inflexion point or the adult weight. Moreover, a sexual dimorphism favouring females was observed in this paternal line. Results demonstrated that the selection programme had improved ADG without variations in adult body weight but, after 37 generations of selection, this trait seems exhausted. Given the reduction in the cumulative reproductive performance and as a consequence in the selection pressure, or possibly/perhaps due to an unexpected effect, rederivation could be the cause of this weak selection response observed from generation 18 onwards.

Long-Term Effects Following Fresh/Vitrified Embryo Transfer Are Transmitted by Paternal Germline in a Large Size Rabbit Cohort

The concept of developmental programming suggests that the early life environment influences offspring phenotype in later life, whose effects may also be manifested in further generations. Valuable pieces of evidence come from the fields applying assisted reproductive technologies (ARTs), which deprive embryos of their optimal maternal environment and were thus associated with subsequent developmental deviations. Recently, we demonstrated that the in vitro manipulations during a vitrified embryo transfer procedure incurs a cumulative and transgenerational decline in the growth performance of the resulting offspring. Here, we provide a longitudinal study to investigate whether previous developmental deviations could be indistinctly paternally or maternally transmitted using crossbred mattings. Our findings revealed that early embryo manipulations through fresh and vitrified embryo transfer incurred paternally transmissible effects over the growth pattern and adult body weight, which seemed not inheritable via the female germline. Similar inheritable effects were observed after fresh and vitrified embryo transfer, suggesting that disturbing optimal embryo development through in vitro manipulations was the principal trigger of transmissible effects, rather than embryo cryopreservation per se.

Long-term and transgenerational phenotypic, transcriptional and metabolic effects in rabbit males born following vitrified embryo transfer

The advent of assisted reproductive technologies (ART) in mammals involved an extraordinary change in the environment where the beginning of a new organism takes place. Under in vitro conditions, in which ART is currently being performed, it likely fails to mimic optimal in vivo conditions. This suboptimal environment could mediate in the natural developmental trajectory of the embryo, inducing lasting effects until later life stages that may be inherited by subsequent generations (transgenerational effects). Therefore, we evaluated the potential transgenerational effects of embryo exposure to the cryopreservation-transfer procedure in a rabbit model on the offspring phenotype, molecular physiology of the liver (transcriptome and metabolome) and reproductive performance during three generations (F1, F2 and F3). The results showed that, compared to naturally-conceived animals (NC group), progeny generated after embryo exposure to the cryopreservation-transfer procedure (VT group) exhibited lower body growth, which incurred lower adult body weight in the F1 (direct effects), F2 (intergenerational effects) and F3 (transgenerational effects) generations. Furthermore, VT animals showed intergenerational effects on heart weight and transgenerational effects on liver weight. The RNA-seq data of liver tissue revealed 642 differentially expressed transcripts (DETs) in VT animals from the F1 generation. Of those, 133 were inherited from the F2 and 120 from the F3 generation. Accordingly, 151, 190 and 159 differentially accumulated metabolites (DAMs) were detected from the F1, F2 and F3, respectively. Moreover, targeted metabolomics analysis demonstrated that transgenerational effects were mostly presented in the non-polar fraction. Functional analysis of molecular data suggests weakened zinc and fatty acid metabolism across the generations, associated with alterations in a complex molecular network affecting global hepatic metabolism that could be associated with the phenotype of VT animals. However, these VT animals showed proper reproductive performance, which verified a functional health status. In conclusion, our results establish the long-term transgenerational effects following a vitrified embryo transfer procedure. We showed that the VT phenotype could be the result of the manifestation of embryonic developmental plasticity in response to the stressful conditions during ART procedures.

Long-Term Phenotypic and Proteomic Changes Following Vitrified Embryo Transfer in the Rabbit Model

Nowadays, assisted reproductive technologies (ARTs) are considered valuable contributors to our past, but a future without their use is inconceivable. However, in recent years, several studies have evidenced a potential impact of ART on long-term development in mammal species. To date, the long-term follow-up data are still limited. So far, studies have mainly focused on in vitro fertilization or in vitro culture, with information from gametes/embryos cryopreservation field being practically missing. Herein, we report an approach to determine whether a vitrified embryo transfer procedure would have long-term consequences on the offspring. Using the rabbit as a model, we compared animals derived from vitrified-transferred embryos versus those naturally conceived, studying the growth performance, plus the weight throughout life, and the internal organs/tissues phenotype. The healthy status was assessed over the hematological and biochemical parameters in peripheral blood. Additionally, a comparative proteomic analysis was conducted in the liver tissue to investigate molecular cues related to vitrified embryo transfer in an adult tissue. After vitrified embryo transfer, birth weight was increased, and the growth performance was diminished in a sex-specific manner. In addition, vitrified-transferred animals showed significantly lower body, liver and heart weights in adulthood. Molecular analyses revealed that vitrified embryo transfer triggers reprogramming of the liver proteome. Functional analysis of the differentially expressed proteins showed changes in relation to oxidative phosphorylation and dysregulations in the zinc and lipid metabolism, which has been reported as possible causes of a disturbed growth pattern. Therefore, we conclude that vitrified embryo transfer is not a neutral procedure, and it incurs long-term effects in the offspring both at phenotypic and molecular levels. These results described a striking example of the developmental plasticity exhibited by the mammalian embryo.

Developmental Plasticity in Response to Embryo Cryopreservation: The Importance of the Vitrification Device in Rabbits

Simple Summary

This study was conducted to demonstrate how embryo manipulation techniques incur phenotypic changes throughout life. This study reports the first evidence demonstrating that the vitrification device used is not a trivial decision, providing valuable information about how the cooling–warming rates during vitrification can be partly responsible of the postnatal phenotypic variations.

Abstract

In this study, we evaluated the effect of embryo vitrification using two different devices on adulthood phenotype in rabbits. In vitro development, prenatal embryo survival, body weight, growth performance, haematological and biochemical peripheral blood analysis, reproductive performance, and lactation performance traits were compared between the experimental groups. They derived from naturally-conceived embryos (NC), fresh-transferred embryos (FT), vitrified-transferred embryos using mini-straw (VTs), or vitrified-transferred embryos using Cryotop (VTc). Straw-vitrified embryos exhibited lower in vitro developmental rates and in vivo survival rates following embryo transfer compared to its Cryotop-vitrified counterparts. Moreover, the VTs group exhibited higher foetal losses than VTc, FT, and NC groups. Independently of the vitrification device, vitrified-transferred (VT) offspring showed a skewed sex ratio in favour of males, and an increased birth bodyweight. In contrast, postnatal daily growth was diminished in all ART (i.e., FT and VT) animals. In adulthood, significant differences in body weight between all groups was founded—all ART progenies weighed less than NC animals and, within ART, VT animals weighed less than FT. For VT groups, weight at adulthood was higher for the VTs group compared with the VTc group. Peripheral blood parameters ranged between common values. Moreover, no differences were found in the fertility rates between experimental groups. Furthermore, similar pregnancy rates, litter sizes, and the number of liveborns were observed, regardless of the experimental group. However, decreased milk yield occurred for VTc and FT animals compared to VTs and NC animals. A similar trend was observed for the milk composition of dry matter and fat. Concordantly, reduced body weight was found for suckling kits in the VTc and FT groups compared to VTs and NC animals. Our findings reveal that developmental changes after the embryo vitrification procedure could be associated with an exhibition of the embryonic developmental plasticity. Moreover, to our best knowledge, this study reports the first evidence demonstrating that the vitrification device used is not a trivial decision, providing valuable information about how the cooling–warming rates during vitrification can be partly responsible of the postnatal phenotypic variations.

Endometrial autotransplantation in rabbits: Potential for fertility restoration in severe Asherman's syndrome

OBJECTIVE

Uterine transplantation is now considered a feasible treatment for women with absolute uterine factor infertility and has been successfully performed for a woman with Asherman's syndrome (AS). The endometrium is a clinically and histologically distinct entity from the surrounding myometrium. Endometrial transplantation (ETx) may offer a less invasive option, with less immunogenic impact, to restore fertility in women with severe AS. The objective of this study was to assess the feasibility of ETx by evaluating surgical and reproductive outcomes following endometrial autotransplantation in a rabbit model.

STUDY DESIGN

A longitudinal study assessing surgical, biochemical, radiological, reproductive and histological outcomes following endometrial autotransplantation in ten New Zealand white rabbits.

RESULTS

Ten procedures were performed, including 8 endometrial auto-transplants (ETx) and 2 endometrial resections (ER), to control against endometrial regeneration. Eight procedures were successful, whereas two rabbits from the ETx group died intra-operatively. Three rabbits were euthanised at 48, 72 and 96 h post-operatively to assess gross and histological appearances. Two rabbits, one from the ETx group and one from the ER group, died four weeks and eight weeks post-operatively. Three rabbits subsequently underwent two cycles of in-vitro fertilization. The first cycle resulted in an implantation rate of 57% in the un-operated uteri. In two rabbits who underwent ETx, an implantation rate of 28.6% was seen. In the second cycle, an implantation rate of 61.9 % (13 implantations) was observed in the control uteri. In the two ETx females, an implantation rate of 14.3 % was seen. No pregnancies were seen in either cycle in the animals who underwent ER. Despite successful implantations in both cycles in the ETx rabbits, no livebirths were achieved. Following death or euthanasia there was gross and microscopic evidence of viable endometrium following ETx, but not following ER.

CONCLUSION

This study has revealed, for the first time, the feasibility of ETx with gross and microscopic evidence of viable endometrium, and the demonstration of clinical pregnancies. Whilst further studies are essential, and the achievement of successful livebirths fundamental, ETx may offer a potential fertility restoring opportunity for women with severe, treatment refractory cases of AS.

Draft Genome Sequences of 12 Monophasic Salmonella enterica subsp. enterica Serotype Typhimurium 1,4,[5],12:i:- Strains Isolated from Wild Griffon Vultures in Eastern Spain

Monophasic Salmonella enterica subsp. enterica serovar Typhimurium is one of the most common zoonotic pathogens. Salmonella species reside in a wide variety of hosts, including wild animals. Thus, we report here the genome sequences of 12 monophasic S. Typhimurium strains isolated from healthy wild vultures to gain better insight into their epidemiology and host-pathogen interactions.

Wild Bonelli's eagles (Aquila fasciata) as carrier of antimicrobial resistant Salmonella and Campylobacter in Eastern Spain

Wild birds have repeatedly been found to be involved in the dissemination of enteric bacterial pathogens in the environment. The aim of this study was to determine the occurrence of Salmonella and Campylobacter as well as the antimicrobial resistance in wild Bonelli's eagles nestlings in Eastern Spain. In addition, we compared the efficiency of two sampling methods (fresh faecal samples from nest and cloacal swabs from nestlings) for detection of both bacteria. A total of 28 nests with 45 nestlings were analysed. In the nest, Salmonella occurrence was 61 ± 9.2%, while Campylobacter occurrence was 11 ± 5.8% (p < 0.05). In the nestlings, Salmonella occurrence was 36 ± 7.1%, while Campylobacter occurrence was 11 ± 4.7% (p < 0.05). Eight Salmonella serovars were identified, and the most frequently isolated were S. Enteritidis, S. Typhimurium, S. Houston, and S. Cerro. Only one Campylobacter species was identified (C. jejuni). Regarding antimicrobial resistance, the Salmonella strains isolated were found to be most frequently resistant to ampicillin and to tigecycline; however, the sole Campylobacter strain recovered was multidrug resistant. In conclusion, this study demonstrated that wild Bonelli's eagles nestlings are greater carriers of Salmonella than of Campylobacter. Both Salmonella and Campylobacter isolates exhibited antimicrobial resistance. In addition, faecal samples from nests were most reliable for Salmonella detection, while cloacal swab from nestlings were most reliable for Campylobacter detection.

Tissue-specific decellularized endometrial substratum mimicking different physiological conditions influences in vitro embryo development in a rabbit model

In the last decades, the decellularization (DC) of organs has become an established technique in the field of regenerative medicine to yield complex and vascularized bioscaffolds. Furthermore, it has been demonstrated in vitro that these decellularized scaffolds retain their native tissue-specificity. This is also the case when this tissue-specific extracellular matrix (ECM) is solubilized and used as hydrogels or coatings to create a biomimetic environment. In this study we investigated if this specificity not only remains when applied to distinct tissues but even more, that these differences can be distinguished within the same tissue at different stages of proliferation. To address this question, a sensitive in vitro animal model was used: rabbit embryos at the third day of development were cultured on coatings made from acellular endometrium that was non-proliferating (non-synchronous, NS) and proliferating (synchronous with the embryo, S) and their development was compared. For this, we obtained whole NS and S rabbit uteri and subjected them to an adapted decellularization protocol. The acellular endometrium was carefully separated by microdissection and converted into a pre-gel solution to be used as hydrogels and coatings for in vitro assays. First, the characteristics of these NS and S hydrogels were investigated by proteomic analysis, electron microscopy and gelling kinetics. When used as substrata for day 3 embryos culture, it became apparent that only the acellular ECM from synchronous endometrial coating achieved similar results to the gold standard culture protocols and conditions, possibly because of the slow release of growth factors present in the synchronous/proliferating endometrium. STATEMENT OF SIGNIFICANCE: It has been shown by in vitro culture of stem cells, progenitor cells and primary culture cells that decellularized tissues retain their specific functions and biochemical and structural compositions. The present work demonstrates that using a mild SDS and perfusion based decellularization (DC) protocol not only effectively decellularize whole rabbit uteri, adding to the growing field of reproductive tissue engineering, but more importantly that the differences in the proliferating endometrium are translated after DC. This implies that DC not only retains the interspecificity of tissues but also the intraspecificity of a developing hormonally stimulated tissue. For the first time, we demonstrate that the coating from decellularized synchronous endometrium acts as a biological support for in vitro embryo development, achieving comparable results with the current gold standard that only uses serum-containing media.

Supplementary feeding stations for conservation of vultures could be an important source of monophasic Salmonella typhimurium 1,4,[5],12:i:

Vultures are nature's most successful scavengers, feeding on the carcasses of dead animals present in the field. Availability of domestic carrion has been unstable due to rapidly changing agro-grazing economies and increasing sanitary regulations that may require burial or burning of livestock carcasses. Thus, several griffon vulture (Gyps fulvus) recoveries are based on European legislation that guarantees the animals' welfare, avoids intense persecution of the vultures and allows the feeding of threatened wildlife in supplementary feeding stations (SFS). However, in recent years, many studies have speculated on the likelihood that avian scavengers may be infected by feeding on pig carcasses at SFS from intensive livestock. In this context, the present study evaluated whether free-living griffon vultures and pig farms share zoonotic Salmonella strains to test the hypothesis that vulture are infected during consumption of carcasses provided at SFS. Here, the occurrence, serotypes and genomic DNA fingerprinting (phage typing and pulsed-field gel electrophoresis) of isolated strains were carried out in griffon vultures and pig farms authorised to provided carcasses at SFS in Castellón province (eastern Spain). The bacteriological analyses revealed that 21.1% of vultures and 14.5% for pig farms samples tested were Salmonella-positive. Monophasic S. typhimurium 1,4,[5],12:i:- was the most frequently isolated serovar. Comparison of Salmonella strains isolated from vultures and pig farms revealed that monophasic S. typhimurium 1,4,[5],12:i:-, S. Derby and S. Rissen strains were highly genetically homogeneous (similar DNA fingerprint). In conclusion, the current study indicates that free-living griffon vultures and pig farms that provide the carcasses at SFS share several zoonotic Salmonella strains. On this basis, and although transmission could be bidirectional, our result seems to corroborate the pig carcasses-to-vulture transmission and cross-infection at SFS. As an immediate Salmonella control strategy in wild avian scavengers, we suggest the implementation of a programme to guarantee that solely pig carcasses from Salmonella-free farms arrive at SFS.

Correction: Successful re-establishment of a rabbit population from embryos vitrified 15 years ago: The importance of biobanks in livestock conservation

[This corrects the article DOI: 10.1371/journal.pone.0199234.].

Effect of restricted feeding under rearing on reproduction, body condition and blood metabolites of rabbit does selected for growth rate

Young rabbit females selected for growth rate can have nutritional needs which may not be met by the common practice of feed restriction during rearing in commercial rabbit production. The aim of this study was to analyse the effect of two different feeding programmes: restricted and ad libitum feeding, applied in young rabbit females for one month at the end of rearing, on reproductive performance, body condition and circulating metabolic hormones and metabolites in a rabbit line selected by growth rate in 3 consecutive reproductive cycles. Thus, twenty-four 16-week-old does were randomly assigned to a group in which the daily recommended nutrient intakes were satisfied (fed restricted: 130 g/day, n=13) or a group fed to satiety (ad libitum: 235.5 g/day, n=11) during one month. Then, all does were inseminated in 3 consecutive cycles using a 42-day reproductive cycle. Measurements of does’ body weight, perirenal fat thickness and plasma leptin, non-esterified-fatty-acids (NEFA), beta-hydroxybutyrate (BOHB) and fructosamine were performed at artificial insemination (AI), parturition and weaning time in 3 consecutive cycles. Reproductive performance of does was evaluated based on fertility, litter size at parturition, prolificacy and productivity. Differences in body weight were found only in the 1^st cycle, ad libitum fed females being heavier than restricted ones. Nevertheless, body weight variances disappeared in later cycles. No differences were found in perirenal fat thickness. Finally, in ad libitum fed females slight differences were found in plasma levels of NEFAs (452 vs. 258 μekv/L and 527 vs. 306 μekv/L for 1^st and 2^nd cycles) and BOHB (0.26 vs. 0.03 mM for 2^nd cycle), but disappeared in the 3^rd reproductive cycle. Fertility, prolificacy and productivity was not significantly affected by the feeding programme. Nevertheless, total litter size showed to be higher in ad libitum fed females at second parturition (8.7 vs. 5.9 kits). Therefore, the evaluated feeding programmes until first AI in females selected by growth rate had no effect on their reproductive outcomes, as the global reproductive performance was not affected.

Rabbit seminal plasma proteome: The importance of the genetic origin

The present study was conducted to characterise rabbit seminal plasma proteins (SP proteins) focusing on the influence of the genetic origin and seasonality. In addition, β-NGF protein quantity in SP was determined. Semen samples were recovered from January to December 2014 using 6 males belonging to genotype A and six from genotype R. For each genotype, one pooled sample at the beginning, middle and end of each season was selected to develop the experiment. A total of 24 pools (3 for each season and genetic line) were analysed. SP proteins of the two experimental groups were recovered and subjected to in-solution digestion nano LC-MS/MS and bioinformatics analysis. The resulting library included 402 identified proteins validated with ≥95% Confidence (unused Score ≥ 1.3). These data are available via ProteomeXchange with identifier PXD006308. Only 6 proteins were specifically implicated in reproductive processes according to Gene Ontology annotation. Twenty-three proteins were differentially expressed between genotypes, 11 over-expressed in genotype A and 12 in genotype R. Regarding the effect of season on rabbit SP proteome, results showed that there is no clear pattern of protein variation throughout the year. Similar β-NGF relative quantity was observed between seasons and genotypes. In conclusion, this study generates the largest library of SP proteins reported to date in rabbits and provides evidence that genotype is related to a specific abundance of SP proteins.

Extra-uterine (abdominal) full term foetus in a 15-day pregnant rabbit

BACKGROUND

While ectopic pregnancies account for 1-2% of all pregnancies, abdominal pregnancy is extremely rare, accounting for approximately 1% of ectopic pregnancies. Extrauterine abdominal pregnancy is defined as the implantation and development of an embryo in the peritoneal cavity. The present report is the first of an incidental case of abdominal pregnancy within four full-term foetus simultaneously with 2 weeks of physiological gestation in a healthy doe rabbit.

CASE PRESENTATION

The doe was born on November 3, 2014 and the first partum took place on May 18, 2015. The doe had previously delivered and weaned an average of 12.0 ± 1.41 live kits at birth (no stillbirths were recorded) during 5 consecutive pregnancies. The last mating was on December 18, 2015 and the detection of pregnancy failure post breeding (by abdominal palpation) on December 31, 2015. Then, the doe was artificially inseminated on January 27, 2016, diagnosed pregnant on February 11, 2016 and subsequently euthanized to recover the foetus. A ventral midline incision revealed a reproductive tract with 12 implantation sites with 15 days old foetus and 4 term foetus in abdominal cavity. There were two foetus floating on either side of the abdominal cavity and two suspended near the greater curvature of the stomach. They were attached to internal organs by means of one or 2 thread-like blood vessels that linked them to the abdominal surfaces.

CONCLUSIONS

In our opinion a systematic monitoring of rabbit breeding should be included to fully understand and enhance current knowledge of this phenomenon of abdominal pregnancy.

Overweight in young males reduce fertility in rabbit model

Semen quality has certainly declined over the past few decades, possibly owing to modern lifestyle factors. In this sense, the role of overweight and obesity in the development of subfertility in males has generated a considerable amount of interest in recent years. However, there is no consensus on whether overweight or obesity impaired sperm quality. Thus, based on the ongoing debate about risk factors for subfertility associated with overweight and obesity in men, this study was designed to investigate the effect of overweight on sperm quality parameters and fertility success in randomized controlled trial in a rabbit model. Fourteen male rabbits were randomly assigned to a control group in which nutritional requirements were satisfied or a group fed to satiety from 12 to 32 weeks of age. At 24 weeks of age, semen samples were analysed weekly by conventional semen analysis for 8 weeks. In addition, during the trial female rabbits were artificially inseminated by each male to assess the fertility success and the number of offspring. Young males fed to satiety were associated with a significant increase in body weight (13.6% overweight) and perirenal fat thickness (5%). Male overweight presented a significant decrease in sperm concentration. There were no differences in the remaining sperm parameters. However, male overweight showed a clear and significant decrease in fertility success (control group, 64±8.9% versus fed to satiety group, 35±9.2%), but not in the number of offspring. Taken together, our findings provide new evidence on the loss of fertility induced by overweight in males.

Feed restriction regime in a rabbit line selected for growth rate alters oocyte maturation manifested by alteration in MSY2 gene expression

Young rabbit females selected for growth rate may have nutritional needs, which may not be met with the common practice of feed restriction during rearing in commercial rabbit production. The aim of this study was to analyse whether two different feeding programmes: ad libitum or restricted (130 g/day) feeding, applied in young rabbit females for 1 month at the end of rearing, could modulate the origin of ovulation process and the quality of the oocytes. At 16 weeks of age, 34 females were randomly assigned to restricted or ad libitum feeding, maintaining these conditions for a month. Then, in an initial experiment, transcriptional profiling of hypothalamus-hypophysis tissue was performed to assess failure to ovulate. In the second experiment, the gene expression analysis of some candidate genes related to oocytes quality was performed. Our results demonstrated that neither of the two feeding programmes modified the transcription of hypothalamus-hypophysis tissue, while the only differences in MSYR expression were found in in vivo mature oocytes ready for successful fertilization. Specifically, MSYR was over-expressed in oocytes from females fed ad libitum. MSYR is one of the most abundant proteins in the oocyte and has proven to be a key regulator of maternal RNA transcription and translation. This finding suggests that MSYR gene is a promising gene in our understanding of the relationship between high growth rate and reproductive performance decline.

Effect of gestational and lactational exposure to heat stress on performance in rabbits

<p>Reproductive performance is greatly affected by environmental factors such as temperature. Heat stress (HS) during pregnancy and lactation can influence not only foetal growth but also postnatal development of kits. The aim of this study was to test the effect of HS during gestation and lactation on postnatal growth till Spanish commercial liveweight. To investigate this, 32 primiparous non lactating rabbit does were exposed to 1 of 2 environmental treatments: high temperature (between 25 and 36°C, HS group; n=16) or thermoneutral conditions (between 14 and 20°C, TN group; n=16). Does were allowed to acclimate 30 d before the artificial insemination. At birth, kits were allocated into 4 groups: HS was only applied during gestation (G group; n=54); HS was applied during gestation and lactation period (GL group; n=85); HS was only applied during lactation period (L group; n=60); and TN was applied during gestation and lactation period (C group; n=77). All litters were kept under each experimental environment until weaning at day 30. Then, litters were moved to TN temperatures until slaughter at day 63. Compared with TN does, the HS does presented lower litter size (9.7 and 11.4; P&lt;0.05), litter weight (503.0 vs. 630.5 g; P&lt;0.05) and kit weight at birth (56.6 vs. 61.4 g; P&lt;0.05), as well as a higher stillborn rate (25.4 vs. 9.9%; P&lt;0.05). The kits from does subjected to HS during gestation (G group) had similar postnatal growth compared to offspring from does gestated in TN conditions (C group), whereas kits from does that experienced HS during gestation and lactation (GL group) and during their lactation (L group) presented decreased postnatal growth. Together, these results demonstrate that kits from does that underwent HS during gestation did not alter postnatal growth until Spanish commercial liveweight, whereas HS during lactation resulted in decreased postnatal growth.</p>

Embryo transfer manipulation cause gene expression variation in blastocysts that disrupt implantation and offspring rates at birth in rabbit

OBJECTIVE

In the current study we aimed to evaluate the effect of embryo transfer on gene expression during pre-implantation development and its consequences on implantation rate, offspring rate at birth and embryonic and fetal losses in the rabbit model.

STUDY DESIGN

The mRNA expressions of 8 candidate genes were compared between 6-day-old in vivo-produced embryos (non-manipulated embryos) to those of 6-day-old embryos previously recovery at the third day of development and transferred into recipient rabbit females (manipulated embryos). Furthermore, we compared between both experimental groups the implantation rate and offspring rate at birth and embryonic and fetal losses.

RESULTS

Differences in transcript abundance of OCT4, C1qTNF1, EMP1 and TNFAIP6 were observed in transferred embryos. In addition, lower implantation and offspring rates at birth were obtained in transferred embryos than in the control group. In addition, embryonic losses were significantly higher in the transferred group than in the control. However, fetal losses were similar between groups.

CONCLUSION

The findings of the current study show that embryo transfer manipulation influenced mRNA expression of late blastocysts prior to implantation, resulting in higher gestational losses as a consequence of faulty embryonic implantation.

Tiny Turtles Purchased at Pet Stores are a Potential High Risk for Salmonella Human Infection in the Valencian Region, Eastern Spain

Turtles may be considered unsafe pets, particularly in households with children. This study aimed to assess Salmonella carriage by turtles in pet stores and in private ownership to inform the public of the potential health risk, enabling informed choices around pet selection. During the period between September and October 2013, 24 pet stores and 96 private owners were sampled in the Valencian Region (Eastern Spain). Salmonella identification procedure was based on ISO 6579: 2002 recommendations (Annex D). Salmonella strains were serotyped in accordance with Kauffman-White-Le-Minor technique. The rate of isolation of Salmonella was very high from pet store samples (75.0% ± 8.8%) and moderate for private owners (29.0% ± 4.6%). Serotyping revealed 18 different serotypes among two Salmonella enterica subspecies: S. enterica subsp. enterica and S. enterica subsp. diarizonae. Most frequently isolated serotypes were Salmonella Typhimurium (39.5%, 17/43) and Salmonella Pomona (9.3%, 4/43). Serotypes identified have previously been reported in turtles, and child Salmonella infections associate with pet turtle exposure. The present study clearly demonstrates that turtles in pet stores, as well as in private owners, could be a direct or indirect source of a high risk of human Salmonella infections. In addition, pet stores should advise their customers of the potential risks associated with reptile ownership.

Study of failures in a rabbit line selected for growth rate

<p>Selection for growth rate is negatively related with reproductive fitness. The aim of this work was to analyse the causes of fertility failure in rabbit does selected for growth rate and characterised for reproductive deficiencies (line R). In the experiment, 82 does were divided into 2 groups: naturally mated (NM) and artificially inseminated (AI), to relate luteinizing hormone (LH) concentration with ovulation induction and pregnancy rate by laparoscopic determination. Additionally, in 38 of these females ovulation rate and metabolites determination (leptin, NEFA, BOHB and glucose) were analysed and perirenal fat thickness measurement and live body weight (LBW) determined. The results showed that all ovulated does (both NM and AI) presented higher concentrations of LH than non-ovulated females. In addition, non-ovulated females showed high levels of leptin and BOHB, as well as LBW. Females from line R have an inherit reduced fertility due to ovulation failure as a consequence of a reduction in LH release, which could be explained by a heavier body weight and higher leptin concentrations.</p>

Development of Cheaper Embryo Vitrification Device Using the Minimum Volume Method

This study was designed to compare the efficiency of the Cryotop and Calibrated plastic inoculation loop (CPIL) devices for vitrification of rabbit embryos on in vitro development and implantation rate, offspring rate at birth and embryonic and fetal losses. CPIL is a simple tool used mainly by microbiologists to retrieve an inoculum from a culture of microorganisms. In experiment 1, embryos were vitrified using a Cryotop device and a CPIL device. There were no significant differences in hatched/hatching blastocyst stage rates after 48 h of culture among the vitrified groups (62±4.7% and 62±4.9%, respectively); however, the rates were significantly lower (P<0.05) than those of the fresh group (95±3.4%). In experiment 2, vitrified embryos were transferred using laparoscopic technique. The number of implanted embryos was estimated by laparoscopy as number of implantation sites at day 14 of gestation. At birth, total offspring were recorded. Embryonic and fetal losses were calculated as the difference between implanted embryos and embryos transferred and total born at birth and implanted embryos, respectively. The rate of implantation and development to term was similar between both vitrification devices (56±7.2% and 50±6.8% for implantation rate and 40±7.1% and 35±6.5% for offspring rate at birth); but significantly lower than in the fresh group (78±6.6% for implantation rate and 70±7.2% for offspring rate at birth, P<0.05). Likewise, embryonic losses were similar between both vitrification devices (44±7.2% and 50±6.8%), but significantly higher than in the fresh group (23±6.6%, P < 0.05). However, fetal losses were similar between groups (10±4.4%, 15±4.8% and 8±4.2%, for vitrified, Cryotop or CPIL and fresh, respectively). These results indicate that the CPIL device is as effective as the Cryotop device for vitrification of rabbit embryos, but at a cost of €0.05 per device.

Campylobacter epidemiology from breeders to their progeny in Eastern Spain

While horizontal transmission is a route clearly linked to the spread of Campylobacter at the farm level, few studies support the transmission of Campylobacter spp. from breeder flocks to their offspring. Thus, the present study was carried out to investigate the possibility of vertical transmission. Breeders were monitored from the time of housing day-old chicks, then throughout the laying period (0 to 60 wk) and throughout their progeny (broiler fattening, 1 to 42 d) until slaughter. All samples were analyzed according with official method ISO 10272:2006. Results revealed that on breeder farms, Campylobacter isolation started from wk 16 and reached its peak at wk 26, with 57.0% and 93.2% of positive birds, respectively. After this point, the rate of positive birds decreased slightly to 86.0% at 60 wk. However, in broiler production all day-old chicks were found negative for Campylobacter spp, and the bacteria was first isolated at d 14 of age (5.0%), with a significant increase in detection during the fattening period with 62% of Campylobacter positive animals at the end of the production cycle. Moreover, non-positive sample was determined from environmental sources. These results could be explained because Campylobacter may be in a low concentration or in a non-culturable form, as there were several studies that successfully detected Campylobacter DNA, but failed to culture. This form can survive in the environment and infect successive flocks; consequently, further studies are needed to develop more modern, practical, cost-effective and suitable techniques for routine diagnosis.

Effect of in vitro and in vivo conditions on development of parthenogenetic rabbit embryos after vitrification

Parthenote embryos offer multiple opportunities in biotechnological research, so it is important to analyse the possibilities for their cryopreservation in order to establish a biobank. The aim of this experiment was to determine the effect of culture conditions and vitrification on rabbit parthenogenetic embryos. Parthenotes were cultured under in vivo and in vitro conditions until day 3 (late morula/early blastocyst), when they were vitrified. Immediately after warming, they were newly cultured under in vivo and in vitro conditions till day 6 (blastocyst stage). Both culture conditions showed similar late morula/early blastocyst (0.39±0.056 vs. 0.46±0.043, for in vivo and in vitro, respectively) and blastocyst rates (0.12±0.068 vs. 0.13±0.070, for in vivo and in vitro, respectively). However, no parthenote was recovered when a combination of culture conditions was performed. To our best knowledge, this is the first demonstration of the ability of rabbit parthenogenetic embryos to develop after vitrification, with similar embryo development after in vivo or in vitro culture. Nevertheless, our results highlight the importance of culture conditions on the morphology of parthenote embryos. Therefore, we have described that special attention should be paid on culture conditions to generate parthenote embryos, with a view to their subsequent use, for example in embryonic stem cell production.

Embryo vitrification in rabbits: Consequences for progeny growth

The objective of this research is to examine if there are any effects of the rederivation procedures on rabbit growth pattern and on weight of different organ in adults. For this purpose, three experiments were conducted on two different groups of animals (control group and vitrified-transferred group) to evaluate the possible effect of embryo manipulation (vitrification and transfer procedures) on future growth traits. The first experiment studies body weight from 1 to 9 weeks of age from the two groups. The second experiment describes the growth curve of progeny from experimental groups and analyzes their Gompertz curve parameters, including the estimation of adult body weight. The third experiment has been developed to study if there are any differences in different organ weight in adult males from the two experimental groups. In general, the results indicate that rederivation procedures had effect on the phenotypic expression of growth traits. The results showed that rabbit produced by vitrification and embryo transfer had higher body weight in the first four weeks of age than control progeny. Results from body weight (a parameter) and b parameter estimated by fitting the Gompertz growth curve did not show any difference between experimental groups. However, differences related with growth velocity (k parameter of the Gompertz curve) were observed among them, showing that the control group had higher growth velocity than the vitrified-transferred group. In addition, we found that liver weight at 40th week of age exhibits significant differences between the experimental groups. The liver weight was higher in the control males than in the VF males. Although the present results indicate that vitrification and transfer procedures might affect some traits related with growth in rabbits, further research is needed to assess the mechanisms involved in the appearance of these phenotypes and if these phenotypes could be transferred to the future progeny.

Effect of luteinizing hormone on rabbit ovarian superstimulation and embryo developmental potential

Assisted reproduction technologies require ovarian stimulation to increase the number of oocytes and embryos. Currently, superstimulation is achieved by gonadotropin treatment, but the embryo yield and quality are highly variable. Commonly, commercial preparations derived from pituitary and urinary origin are used to superovulate. Hence, ovarian superstimulation protocols have usually included both FSH and LH. The appearance of recombinant gonadotropins manufactured by genetic engineering techniques has ensured high quality and batch-to-batch consistency. Moreover, this enables us to assess the importance of LH in the ovarian stimulation. The main aim of this study was to evaluate the effect of recombinant human LH supplementation (10%) on embryonic development produced by rabbit does superovulated with low or high concentration (18.75 or 37.50 IU) of recombinant human FSH (rhFSH). Females treated with rhFSH increased the ovulation rate, and it was significantly higher when the high FSH dose was supplemented with LH. The superstimulation treatment used did not significantly affect in vitro development rate until the expanded blastocyst stage. The results of this study seem to suggest that, in terms of superovulatory response, when rabbit does are treated with 37.5-IU rhFSH, the use of LH supplementation allows an increase in the number of follicles recruited and the quality of embryos, in terms of ability to develop in vitro until blastocyst, and the expression profile of OCT4, NANOG, and SOX2 genes is not affected.

Comparison of different sampling types across the rearing period in broiler flocks for isolation of Campylobacter spp

Campylobacter is the most common bacterial cause of human gastrointestinal disease in most developed countries. It is generally accepted that poultry products are a significant source of foodborne Campylobacter infections in humans. Assessing the effectiveness of any potential intervention at farm level requires monitoring of the Campylobacter status of broiler flocks, using appropriate sampling methods. The aim of this study was to assess the influence of the sample type across the rearing period for the detection of Campylobacter spp. at farm level. During this study, 21 commercial broiler farms were intensively sampled. Each farm was visited and sampled at different times during the rearing period (d 1, 7, 14, 21, 28, 35, and 42). On the first day of rearing, the status of the house and the day-old flock was evaluated, and environmental and cecal samples were collected. During rearing, 4 different sample types were collected: feces with sock swabs (sock swabs), feces directly from the litter (feces), cloacal swabs, and cecal content. All samples were analyzed according to ISO 10272-1:2006 (Annex E) and also by direct culture. The results of this study showed that Campylobacter spp. were detected in all of the sample types on d 14 of rearing. From this point on, the detection increased significantly, with a maximum detection rate by the end of rearing, regardless of the sample type. All samples that were negative upon direct culture were also negative after pre-enrichment. At the end of rearing, the percentage of samples positive for Campylobacter spp. was 71.4% for cecal samples, 61.9% for cloacal swabs, 45.2% for sock swabs, and 69.1% for fecal samples. C. jejuni was detected in all the sample types, with positive rates ranging from 67.1 to 76.0% for cecal samples and cloacal content, respectively. Cecal samples, cloacal swabs, and fecal samples cultured by direct plating onto modified charcoal cefoperazone deoxycholate agar (mCCDA) without pre-enrichment have the same sensitivity for detection of Campylobacter spp. in broiler flocks independent of the day of rearing.

First steps of in vitro gastrulation in rabbit vitrified embryos

BACKGROUND

The in vitro rabbit embryo production and their cryopreservation methodologies such as vitrification generate less viable embryos, and occasionally, with significant differences from those that are not subjected to any treatment. Besides, in vitrified rabbit embryos little information is available about exactly when and where begin to emerge the first differences that finally result in foetal losses comparing with non-vitrified embryos.

OBJECTIVE

The aim of this study was to evaluate the vitrification effects on the early in vitro gastrulation events.

MATERIALS AND METHODS

After oviductal transfers of vitrified and non-vitrified embryos (control) in rabbit recipients, blastocysts from 144h (6-day-old) were recovered and cultured into TCM199 supplemented with rabbit homologous serum media for 48 hours. Gastrula stage and measures of perimeter and area of blastocyst and gastrula were noted. Moreover, eight independent pools consisting of six embryos each one were generated for each experimental group (control and vitrified) and total RNA was isolated to study the OCT4 gene expression.

RESULTS

Of 151 control and 164 vitrified morulae transferred, 69.5 % and 70.1 % developed in vivo to 6-day-old blastocyst respectively. After 24 hour of in vitro culture, 41.8 % of vitrified blastocyst had begun the neurulation (stage 5-) versus 22.8 % of control group. Nevertheless, the vitrified group showed the highest percentage of collapsed blastocyst at 48 hours (26.8 %). Non morphometric differences differences were observed in perimeter and area of blastocyst and gastrula between control and vitrified group at 0 and 24 hours. By contrast, perimeter and gastrula areas were slightly higher for the vitrified group than those for the control group at 48 hours of in vitro culture.

CONCLUSION

The study reveal the existence of the first morphological differences in vitrified blastocysts of 7 and 8-day-old, marked by a further development of gastrulation in the vitrified group.