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Este artículo se encuentra disponible en la siguiente URL: https://www.mdpi.com/2306-7381/9/12/663 The objective of this investigation was to determine the ovarian response, fertility, and prolificacy of nulliparous sheep when compared to multiparous sheep after a short-term (7 days) CIDR/eCG treatment which was administered during the non-breeding season. All the multiparous sheep, whereas only 54% of the nulliparous ewes, showed signs of estrus. However, 81.8% of the multiparous sheep and 100% of the nulliparous ewes ovulated. Fertility was also low after short-term progesterone treatments during the anestrous season in maiden sheep (30.8 vs. 72.7% in multiparous ewes). Such results indicate significant differences in the response to CIDR/eCG protocols for induction and synchronization of estrus and ovulation between nulliparous and multiparous sheep during the non-breeding season.

Iberian pigs and its crosses are produced to obtain high-quality meat products. The objective of this work was to evaluate a wide panel of DNA markers, selected by biological and functional criteria, for association with traits related to muscle growth, fatness, meat quality and metabolism. We used 18 crossbred Iberian pigs with divergent postnatal growth patterns for whole genome sequencing and SNP discovery, with over 13 million variants being detected. We selected 1023 missense SNPs located on annotated genes and showing different allele frequencies between pigs with makerdly different growth patterns. We complemented this panel with 192 candidate SNPs obtained from literature mining and from muscle RNAseq data. The selected markers were genotyped in 480 Iberian × Duroc pigs from a commercial population, in which phenotypes were obtained, and an association study was performed for the 1005 successfully genotyped SNPs showing segregation. The results confirmed the effects of several known SNPs in candidate genes (such as LEPR, ACACA, FTO, LIPE or SCD on fatness, growth and fatty acid composition) and also disclosed interesting effects of new SNPs in less known genes such as LRIG3, DENND1B, SOWAHB, EPHX1 or NFE2L2 affecting body weight, average daily gain and adiposity at different ages, or KRT10, NLE1, KCNH2 or AHNAK affecting fatness and FA composition. The results provide a valuable basis for future implementation of marker-assisted selection strategies in swine and contribute to a better understanding of the genetic architecture of relevant traits.

A study was undertaken to assess the impact of the timing of grazing on rumen and plasma metabolites and some metabolic hormones in lactating dairy sheep allocated to an Italian ryegrass (Lolium multiflorum Lam) pasture in spring for 4 h/d. Twenty-four mid lactation Sarda ewes stratified for milk yield, body weight, and body condition score, were divided into four homogeneous groups randomly allocated to the treatments (2 replicate groups per treatment). Treatments were morning (AM, from 08:00 to 12:00) and afternoon pasture allocation (PM, from 15:30 to 19:30). Samples of rumen liquor (day 39) and blood plasma (days 17 and 34 of the experimental period) were collected before and after the grazing sessions. Moreover, on days 11 and 35, grazing time was assessed by direct observation and herbage intake measured by the double weighing procedure. Grazing time was longer in PM than AM ewes (P < 0.001) but herbage intake was undifferentiated between groups. The intake of water-soluble carbohydrates at pasture was higher in PM than AM ewes (P < 0.05). The post-grazing propionic and butyric acid concentration, as measured on day 39, were higher in PM than AM ewes (P < 0.05). The basal level of glucose on day 34 and insulin (on both sampling days) were higher in PM than AM (P < 0.05). The opposite trend was detected for non-esterified fatty acids (P < 0.05, day 34) and urea (both days). Pasture allocation in the afternoon rather than in the morning decreased plasma concentration of ghrelin (P < 0.001) and cortisol (P < 0.001), with a smoothed trend on day 34 in the latter variable. To conclude, postponing the pasture allocation to afternoon increased the intake of WSC, favoring a glucogenic pattern of rumen fermentation and a rise of glucose and insulin levels in blood, although these effects were not consistent across the whole experimental period. Moreover, the afternoon grazing decreased the level of cortisol and ghrelin, suggesting a higher satiation-relaxing effect.

In most female mammals, a common drawback to multiple ovulation embryo transfer programs is the variability in the superovulatory response to the multidose pFSH treatment. The aim of the present study was to identify embryo donor goats based on their response to superovulation before the performance of a high-cost hormonal treatment, as we have previously done in sheep. To this end, we evaluated the number of ovulations obtained in response to the administration of a one-shot eCG treatment and related it with the subsequent ovarian response to a multiple-dose pFSH treatment in 33 goats of the Criolla-Neuquina breed. Goats received a one-shot eCG treatment of 800 IU at the end of a 17-day progestational treatment; 9 days later, started a second 17-day progestational treatment and then received a multiple-dose pFSH treatment on days 15-17 (116 mg pFSH, in six decreasing doses). The number of corpora lutea (CL) per goat was recorded laparoscopically after both hormonal treatments. On day 8 after the second pessary removal, embryos were surgically recovered and classified by quality. Results showed a significant positive correlation between the number of CL obtained in response to the eCG and pFSH treatments (r = 0.41; y = 0.8352x + 6.9906; P 0.05), although of limited value to select high ovulatory responding goats, due to its low correlation value. Then, goats were grouped into high and low ovulatory responders to the eCG (High ≥9; Low9 CL) and pFSH treatments (High ≥13; Low13 CL). After the eCG and pFSH treatments, 60% of the goats maintained their classification as high or low superovulatory responders (expressed as recurrence rate). Significant differences were found in the number of CL (18.2 ± 1.3 vs 9.9 ± 1.3), number of embryos + oocytes (13.5 ± 1.7 vs 7.6 ± 1.7), number of embryos (10.8 ± 1.4 vs 5.1 ± 1.4) and number of Grade 1 and Grade 2 embryos (8.8 ± 1.4 vs 4.3 ± 1.4) between high and low superovulatory responder goats (P 0.05), while no differences were observed in the number of oocytes and in the recovery of embryos + oocytes, embryos, Grade 1 and Grade 2 embryos and fertilization rates (P 0.05). In conclusion, the recurrence rate in ovarian response between the one-shot eCG treatment and the multiple-dose pFSH treatment would confirm the existence of an "individual or intrinsic factor" of the donor goat that would respond as a high or low ovulatory responder to superovulatory treatments.

Departamento de Reproducción Animal​ (INIA), Gonadotropin-releasing hormone (GnRH)-loaded chitosan nanoparticles (GnRH-ChNPs) were used at different doses and routes of administration to induce ovulation in rabbits as an attempt to improve artificial insemination (AI) procedures and outcomes. In this study, the characteristics (size, polydispersity, loading efficiency, and zeta-potential) of GnRH-ChNPs and the GnRH release pattern were determined in an in vitro study. A first in vivo study assessed the pituitary and ovarian response to different GnRH-ChNPs doses and routes of administration (two i.m. doses, Group HM = 0.4 µg and Group QM = 0.2 µg, and two intravaginal doses, Group HV = 4 µg and Group QV = 2 µg) against a control group (C) receiving bare GnRH (0.8 µg). The HM, QM, and HV treatments induced an earlier LH-surge (90 min) than that observed in group C (120 min), whilst the QV treatment failed to induce such LH surge. The number of ovulation points was similar among treatments, except for the QV treatment (no ovulation points). A second in vivo study was consequently developed to determine the hormonal (progesterone, P4, and estradiol, E2) profile and pregnancy outcomes of both HM and HV treatments against group C. The treatment HM, but not the treatment HV, showed adequate P4 and E2 concentrations, conception and parturition rates, litter size, litter weight, and viability rate at birth. Overall, the use of GnRH-ChNPs allows for a reduction in the conventional intramuscular GnRH dose to half without compromising fertility. However, the addition of GnRH-ChNPs to semen extenders, although successfully inducing ovulation, has negative impacts on fertility. Thus, more studies are needed to explore this point and allow further adjustments., This research received no external funding., 14 Pág. (This article belongs to the Collection Nanotechnology in Animal Science)

Twenty-four adult rabbit bucks (n = 6 per treatment) were fed a basal diet supplemented with 0 (control), 50, 100, and 150 mg proline/kg dry matter (DM) diet for 12 weeks to determine possible usefulness for alleviating the negative impact of environmental heat stress on redox status, haemato-biochaemical attributes and semen quality. There were significant dose–response effects, with increments in levels of dietary proline (LDP) quadratically improving red blood cell counts (p = 0.017), rectal temperature (p = 0.009), and respiratory rate (p &lt, 0.001). Increasing LDP cubically affected superoxide dismutase activity in blood plasma (p = 0.012) and total antioxidant capacity in both blood and seminal plasma (p &lt, 0.001 and p = 0.006, respectively). The optimal response was observed at 30 and 80 mg proline/kg DM for blood and seminal plasma, respectively. With regards to homeostasis indexes, increments in LDP cubically modified blood plasma concentrations of total protein (p = 0.002) and albumin (p &lt, 0.001), with an optimal response found at 70 mg proline/kg DM. A linear relationship (p = 0.005) was also observed between LDP and blood plasma glucose concentrations, with the optimal response being found at 100 mg proline/kg DM. Increasing LDP also showed positive effects on reproductive traits, with quadratic increases in blood plasma testosterone and cortisol concentrations (p &lt, 0.001, optimal responses at 50 and 60 mg proline/kg DM, respectively), a positive linear relationship with in libido, ejaculate volume, sperm concentration and total sperm count (p &lt, 0.001 for all, optimal responses observed at 100 mg proline/kg DM) and a quadratic increase in total functional sperm fraction (p &lt, optimal response at 70 mg proline mg/kg DM). Hence, the optimal positive effects of dietary proline supplementation on redox status, blood metabolites, and reproductive traits of rabbit bucks may be achieved at 50–100 mg/kg DM.

Reproductive function and therefore fertility, both in women and men, are affected by the high altitude environment. Hypobaric hypoxia affects functionality of the hypothalamus–hypophysis–gonads axis, sperm quality, cyclic ovulatory activity, and quality of preovulatory follicles, oocytes, corpora lutea, and embryos. Hence, chances for obtaining pregnancy are diminished in humans and animals living at high altitudes. The occurrence of intrauterine growth restriction is around 3-fold higher than that at low altitude. Most of these deficiencies are related not only to hypoxia but also to increased oxidative stress. Hence, supplementation with antioxidant agents may constitute a useful strategy.

Este artículo se encuentra disponible en la siguiente URL: https://www.mdpi.com/2072-6643/14/4/902 Este artículo de investigación pertenece al número especial "Nutrition and Microbiome". Reproductive tract dysbiosis, due to the action of pathogens and/or unhealthy lifestyle, has been related to many reproductive diseases and disorders in mammalian species. Classically, such a problem has been confronted by the administration of antibiotics. Despite their effectiveness for controlling disease, treatments with antibiotics may negatively affect the fertility of males and females and, mainly, may induce antibiotic resistance. Accordingly, safer alternatives for maintaining reproductive system eubiosis, such as probiotics, are required. The present review summarizes the current knowledge on the biodiversity of the microbiota at the reproductive tract, possible changes in the case of dysbiosis, and their relationships with adequate reproductive health and functioning in both females and males. Afterwards, mechanisms of action and benefits of different probiotics are weighed since the biological activities of probiotics may provide a promising alternative to antibiotics for maintaining and restoring reproductive eubiosis and function. However, at present, it is still necessary for further research to focus on: (a) identifying mechanisms by which probiotics can affect reproductive processes; (b) the safety of probiotics to the host, specifically when consumed during sensitive reproductive windows such as pregnancy; and (c) the hazards instructions and regulatory rules required for marketing these biological-based therapies with sufficient safety. Thus, in this review, to draw a comprehensive overview with a relatively low number of clinical studies in this field, we showed the findings of studies performed either on human or animal models. This review strategy may help provide concrete facts on the eligible probiotic strains, probiotics colonization and transfer route, and prophylactic and/or therapeutic effects of different probiotic strains.

This study is aimed at determining the reproductive performance of anestrous ewes treated with nanoencapsulated GnRH after a progesterone-based protocol for estrus induction was proposed as a way of replacing eCG. A total of sixty anestrous, multiparous, non-lactating Barki ewes were randomly allocated into three homogenous groups and subjected to a CIDR-based estrus induction protocol. The first group (eCG) received an intramuscular (i.m.) injection of 350 IU of eCG at CIDR removal. The second (LNGnRH) and third (HLNGnR) groups received either 25 µg or 50 µg of encapsulated GnRH nanoparticles by the i.m. route in the form of spherical GnRH-encapsulated chitosan–TPP nanoparticles (which were 490.8 nm and had a 13.6 mV positive charge) 48 h after CIDR removal. Follicular dynamics, estrous behavior, luteal activity, and pregnancy outcomes were evaluated. Three days after CIDR removal, the number of large follicles increased by similar amounts in the LNGnRH and eCG groups and were significantly higher in both groups than in the HNGnRH group. However, no differences were observed in the numbers and diameters of CLs among the experimental groups and, on the other hand, treatment with HNGnRH significantly increased blood serum progesterone levels compared with eCG and LNGnRH. Treatment with HNGnRH increased conception, lambing, and fecundity rates (p < 0.05), with the trend of a higher litter size (p = 0.081) compared with eCG, whereas LNGnRH resulted in intermediate values. In conclusion, a dose of 50 µg of GnRH encapsulated in chitosan-TPP nanoparticles can be used as an alternative to eCG in progesterone-based estrus induction protocols in sheep.

15Pág., The objective of this study was to investigate the metabolic and osmotic effects of different doses of glycerol or a glycerol - propylene glycol mixture in Sarda sheep with the aim to identify those able to beneficially modify ewe's metabolic status without harmful changes in red blood cell (RBC) indices. Thereafter, the selected doses were tested for their effects on ewe's ovarian activity during an induced follicular phase and compared to the effects of a hormonal treatment with equine chorionic gonadotrophin (eCG)., This study was financed by a doctoral grant from the Italian Ministry of Education, University and Research (Programma Operativo Nazionale Ricerca e Innovazione 2014–2020 - CCI 2014IT16M2OP005 - Fondo Sociale Europeo, Azione I.1 “Dottorati Innovativi con caratterizzazione Industriale). The funding institution financed laboratory analysis, the dietary treatments, and FDS. The funding institution had no role in the design of the study; in the collection, analysis, and interpretation of data; or in the writing of the manuscript.

The role played by microbiota is attracting growing attention within the scientific and medical community, in both human and animal fields, in the last years. Most of the studies have been focused on the intestinal microbiome, whilst little attention has been paid to other systems, like the reproductive tract of both females and males. However, there is a growing body of information showing the interplay between reproductive tract dysbiosis, due to the action of pathogens and/or unhealthy lifestyle, and reproductive disease and disorders in many mammalian species. The present review aims to summarise current knowledge on the biodiversity of the microbiota of the reproductive tract, and the possible relationships between eubiosis or dysbiosis and reproductive health and function in both females and males.

Study question Does sodium tungstate treatment improve embryo implantation and therefore, fertility in large mammals? Summary answer Oral administration of sodium tungstate increases embryo implantation and reproductive efficiency in large mammals. What is known already Sodium tungstate (ST) has shown its capacity to modulate critical molecules in the embryo implantation process. ST showed a positive effect on PCOS-like model to restore ovulation and fertility. Moreover, ST proved to act directly on the endometrium to increase embryo adhesion in in vitro assays. There is an inherent difficulty in studying implantation using in vivo models due to the close communication between ovary, embryo and endometrium. For the current study, the Large-White swine breed has been selected because of its high efficiency in ovulatory and fertilisation processes, minimising low embryo quality interferences in the implantation process. Study design, size, duration A randomised, blinded, prospective, placebo-controlled study was performed to evaluate ST effect on fertility, ovulation, and embryo implantation rates in swine, which is characterised by a high fertilisation rate but a limiting implantation rate. Forty-four primiparous Large-White sows (8 months old) were orally-treated with ST or placebo for 44–46 days, from 10 days prior to starting a progestin-based treatment for ovulation induction to gestational days 11th–13th (i.e., the window of implantation in swine). Participants/materials, setting, methods: Animals were randomised in treatment groups based on body weight ranges and housed individually in temperature-controlled conditions. 2.5g ST (diluted in 5ml of distilled water) or vehicle were once-daily orally administered with a syringe. Sows responding to ovulation-induction protocols were inseminated with high-quality sperm from untreated pigs and euthanised at gestational days 28–30 (1st pregnancy trimester) to recover genital tracts. Pregnancy, number of ovulations, number of viable/non-viable implanted embryos and fetal measurements were immediately recorded. Main results and the role of chance All 44 sows involved in the study responded to ovulation induction and were inseminated, but 4 females were excluded from the study because of uterine anatomical abnormalities (unicornuate uterus) or abnormalities during pregnancy. Hence, 19 ST-treated and 21 placebo sows were eligible.There were no differences in pregnancy rate (pregnancy was observed in 17 ST-treated sows 19 placebo-treated sows; 89.47% and 90.48%, respectively) or number of ovulations (21.5±4.1 vs 21.8±2.9 in placebo and treated animals, respectively; p = 0.300). However, implantation rate was significantly improved in ST-treated animals, since the number of implanted embryo was found to be increased by 15% per sow in the ST-treated group; which means two additional good-quality embryos per sow (16.5±3.2 in the ST group vs 14.4±3.9 in the placebo group, p Limitations, reasons for caution The current study is the first attempt to evaluate ST effect on reproductive outcomes, in healthy large mammals. Having in mind that the selected model is high reproductive efficient, further studies assessing ST effects in infertile and sub-fertile mammals should be performed to elucidate ST activity in suboptimal fertility conditions. Wider implications of the findings: Sodium tungstate treatment proves, for the first time, the improvement of fertility in healthy large mammals. Sodium tungstate treatment improves endometrial implantation and therefore, fertility efficiency. Thus, after subsequent further research, sodium tungstate may become a potential treatment for improving embryo implantation, an unmet medical need. Trial registration number Not applicable

Background: The pathogenesis of renal disease in the context of overweight/obesity, metabolic syndrome, and insulin resistance is not completely understood. This may be due to the lack of a definitive animal model of disease, which limits our understanding of obesity-induced renal damage. We evaluated the changes in renal histology and lipid deposits induced by obesity in a model of insulin resistance: the Iberian swine fed with fat-enriched food. Methods: Twenty-eight female sows were randomized to standard (SD) or high-fat diet (HFD: 6.8% of saturated fat) for 100 days. Weight, adiposity, analytics, oral glucose tolerance tests, and measured renal function were determined. Renal histology and lipid deposits in renal tissue were analyzed. Results: Animals on HFD developed obesity, hypertension, high levels of LDL cholesterol, triglycerides, insulin resistance, and glomerular hyperfiltration. No animal developed overt diabetes. Animals on HFD showed “diabetoid changes”, including mesangial expansion [21.40% ± 4 vs.13.20% ± 4.0, p < 0.0001], nodular glomerulosclerosis [7.40% ± 7, 0.75 vs. 2.40% ± 4.7, p = 0.02], and glomerulomegaly (18% vs. 10%, p = 0.010) than those on SD. Tubular atrophy, interstitial fibrosis, inflammation, arteriolar hyalinosis, or fibrointimal thickening were mild and similar between groups. Triglyceride content in renal tissue was higher in animals on HFD than in SD (15.4% ± 0.5 vs. 12.7% ± 0.7; p < 0.01). Conclusions: Iberian pigs fed with fat-enriched food showed diabetoid changes and glomerulomegaly as observed in obese humans making this model suitable to study obesity-induced renal disease.

Este artículo se encuentra disponible en la página web de la revista en la siguiente URL: https://journals.physiology.org/doi/full/10.1152/japplphysiol.00303.2019?rfr_dat=cr_pub++0pubmed&url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org This is the pre-peer reviewed version of the following article: Almendros, I., Martínez-Ros, P., Farré, N., Rubio-Zaragoza, M., Torres, M., Gutiérrez-Bautista, A.J. et al. (2019). Placental oxygen transfer reduces hypoxia-reoxygenation swings in fetal blood in a sheep model of gestational sleep apnea. Journal of Applied Physiology, vol. 127, i. 3 (13 sep.), pp. 745-752, which has been published in final form at https://doi.org/10.1152/japplphysiol.00303.2019. Este es el pre-print del siguiente artículo: Almendros, I., Martínez-Ros, P., Farré, N., Rubio-Zaragoza, M., Torres, M., Gutiérrez-Bautista, A.J. et al. (2019). Placental oxygen transfer reduces hypoxia-reoxygenation swings in fetal blood in a sheep model of gestational sleep apnea. Journal of Applied Physiology, vol. 127, i. 3 (13 sep.), pp. 745-752, que se ha publicado de forma definitiva en https://doi.org/10.1152/japplphysiol.00303.2019. AIM: Obstructive sleep apnea (OSA), characterized by events of hypoxia reoxygenation, is highly prevalent in pregnancy, negatively affecting the gestation process and particularly the fetus. Whether the consequences of OSA on the fetus and offspring are mainly caused by systemic alterations in the mother or by direct effect of intermittent hypoxia in the fetus is unknown. In fact, how apnea-induced hypoxemic swings in OSA are transmitted across the placenta remains to be investigated. The aim of this study was to test the hypothesis, based on a theoretical background on the dampening effect of oxygen transfer in the placenta, that oxygen partial pressure (PO2) swings resulting from obstructive apneas mimicking OSA are mitigated in the fetal circulation. METHODS: To this end, 4 anesthetized ewes close to term pregnancy were subjected to obstructive apneas consisting of 25-s airway obstructions. Real time PO2 was measured in the maternal carotid artery and in the umbilical vein using fast-response fiberoptic oxygen sensors. RESULTS: The amplitude of PO2 swings in the umbilical vein were considerably smaller (3.1±1.0 vs. 21.0±6.1 mmHg (m±SE); p

The effects of a combined supplementation with herbal antioxidants during pregnancy on reproductive traits and piglet performance (number of live, dead, and mummified newborns and litter weight at birth and individual body weight at both birth and weaning) were assessed in a total of 1027 sows (504 treated and 523 control females) kept under commercial breeding conditions. The supplementation increased the number of live-born piglets (13.64 ± 0.11 vs. 12.96 ± 0.13 in the controls, p = 0.001) and the total litter weight, decreasing the incidence of low-weight piglets without affecting the number of stillbirths and mummified newborns. Such an effect was modulated by the number of parity and the supplementation, with supplementation increasing significantly the number of living newborns in the first, second, sixth, and seventh parities (0.87, 1.10, 1.49, and 2.51 additional piglets, respectively, p &lt, 0.05). The evaluation of plasma vitamin concentration and biomarkers of oxidative stress (total antioxidant capacity, TAC, and malondialdehyde concentration, MDA) performed in a subset of farrowing sows and their lighter and heavier piglets showed that plasma levels of both vitamins were significantly higher in the piglets than in their mothers (p &lt, 0.05 for vitamin C and p &lt, 0.005 for vitamin E), with antioxidant supplementation increasing significantly such concentrations. Concomitantly, there were no differences in maternal TAC but significantly higher values in piglets from supplemented sows (p &lt, 0.05). On the other hand, supplementation decreased plasma MDA levels both in the sows and their piglets (p &lt, 0.05). Finally, the piglets from supplemented mothers showed a trend for a higher weaning weight (p = 0.066) and, specifically, piglets with birth weights above 1 kg showed a 7.4% higher weaning weight (p = 0.024). Hence, the results of the present study, with high robustness and translational value by offering data from more than 1000 pregnancies under standard breeding conditions, supports that maternal supplementation with herbal antioxidants during pregnancy significantly improves reproductive efficiency, litter traits, and piglet performance.

15 Pág. Departamento de Reproducción animal, Intrauterine growth restriction (IUGR) refers to poor growth of a fetus during pregnancy due to deficient maternal nutrition or oxygen supply. Supplementation of a mother's diet with antioxidants, such as hydroxytyrosol (HTX), has been proposed to ameliorate the adverse phenotypes of IUGR. In the present study, sows were treated daily with or without 1.5 mg of HTX per kilogram of feed from day 35 of pregnancy (at 30% of the total gestational period), and fetuses were sampled at day 100 of gestation. Fetuses were classified as normal body weight (NBW) or low body weight (LBW) as a consequence of IUGR, constituting four groups: NBW-Control, NBW-HTX, LBW-Control, and LBW-HTX. The brain was removed, and the hippocampus, amygdala, and prefrontal cortex were rapidly dissected. Neuronal markers were studied by immunohistochemistry, and a decrease in the number of mature neurons in the hippocampal Cornu Ammonis subfield 1 (CA1) and the Dentate Gyrus (DG) regions was observed in LBW fetuses together with a higher number of immature neurons and other alterations in neuronal morphology. Furthermore, IUGR conditions altered the neurotransmitter (NT) profile, since an increase in the serotonin (5-HT) pathway was observed in LBW fetuses. Supplementation with HTX was able to reverse the morphological and neurochemical changes, leading both characteristics to values similar to those of NBW fetuses., This research was funded by the Spanish Ministry of Economy and Competitivity (AGL2015-68463-C2-2-P to AB and projects AGL2013-48121-C3-R and AGL2016-79321-C2–1-R to AGB), co-funded by FEDER. NY and MVG are recipients of a graduate student fellowship from the Spanish FPU National Program Grant (Ministry of Science, Innovation and Universities; number FPU17/01881 and FPU14/01285) and CGC is recipient of a FPI National Program Grant (number BES-2014-070464).

Currently, there is an intense effort to find an alternative hormone to eCG to induce ovulation after estrus synchronization treatments in sheep. One of the proposed alternatives is based on the use of hCG, but the results are controversial since fertility rates are commonly affected. The present study aims to evaluate, therefore, the adequacy of hCG in protocols for the synchronization of estrus and ovulation. Ovarian follicle dynamics, occurrence of estrus behavior and subsequent ovulation, quality of corpora lutea, and pregnancy rate after controlled natural mating were assessed in two consecutive trials. The findings indicate that the low fertility rates reported for the protocols based on the administration of hCG for inducing ovulation during estrus synchronization in sheep may be related to a high occurrence of abnormal follicular growth patterns, disturbances, and retardments of ovulation and concomitant formation of follicular cysts in the treated females. These results preclude their practical application to induce ovulation concomitantly to estrous synchronization treatments. Estación Experimental Agropecuaria Bariloche Fil: Bruno Galarraga, María Macarena. Instituto Nacional de Tecnología Agropecuaria (INTA). Estacion Experimental Agropecuaria Bariloche. Laboratorio de Reproducción de Rumiantes Menores; Argentina Fil: Bruno Galarraga, María Macarena. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; Argentina Fil: Cano Moreno, Virginia. Universidad Cardenal Herrera-CEU. Facultad de Veterinaria. Departamento Produccion y Sanidad Animal; España Fil: Lago Cruz, Beatriz. Universidad Complutense de Madrid. Facultad de Veterinaria. Departamento de Toxicologia y Farmacologia; España Fil: Encinas, Teresa. Universidad Complutense de Madrid. Facultad de Veterinaria. Departamento de Toxicologia y Farmacologia; España Fil: Gonzalez Bulnes, Antonio. Universidad Cardenal Herrera-CEU. Facultad de Veterinaria. Departamento Produccion y Sanidad Animal; España Fil: Martinez Ros, Paula. Universidad Cardenal Herrera-CEU. Facultad de Veterinaria. Departamento Produccion y Sanidad Animal; España

The aim was to evaluate pregnancy success after transfer of embryos vitrified in micropipette tips in Merino sheep under extensive conditions. A second objective was to evaluate the influence of embryo stage in such pregnancy rate. One hundred and twenty-seven embryos were rewarmed and transferred into recipient ewes. On rewarming, the embryos were placed into three-step cryoprotectant dilutions. Finally, prior to transfer to recipient females, embryos were maintained in Basic Medium for 5 min at 25ºC and were re-evaluated by morphological criteria; all degenerated embryos were eliminated. Recipient ewes (n = 150) were treated for estrus with sponges placed for 14 days and 300 IU of eCG. At embryo transfer, three experimental groups were defined: morulae transferred on Day 7, blastocysts transferred on Day 7 and blastocysts transferred on Day 8 after sponge removal. In all groups, semi-laparoscopic transfer of one rewarmed embryo per recipient was performed. Pregnancy was diagnosed by ultrasonography on day 28 after embryo transfer. The embryo selection rate after rewarming was higher for blastocysts (89.3% - 67/75) compared to morulae (65.9% - 60/91) (P < 0.05). Pregnancy diagnosis showed a 38.3% (23/60) of success after morula transfer on Day 7 post progestagen removal. The day of transfer showed a significant influence on pregnancy rate after blastocyst transfer (Day 8, 55.9% - 19/34 vs Day 7, 21.2% - 7/33) (P < 0.05). Blastocysts transfer on Day 8 showed the highest global efficiency (pregnancies/total embryos after rewarming) (47.5% - 19/40) (P < 0.05). In conclusion, reproductive efficiency obtained by vitrified embryo transfer allows its recommendation for embryo transfer programs under extensive conditions. The importance of considering the synchrony between the embryo age and the recipient uterus stage is emphasized. Fil: Gibbons, Alejandro Eduardo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Estación Experimental Agropecuaria San Carlos de Bariloche. Instituto de Investigaciones Forestales y Agropecuarias Bariloche. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; Argentina Fil: Fernandez, Jimena. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Estación Experimental Agropecuaria San Carlos de Bariloche. Instituto de Investigaciones Forestales y Agropecuarias Bariloche. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; Argentina Fil: Bruno Galarraga, María Macarena. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Estación Experimental Agropecuaria San Carlos de Bariloche. Instituto de Investigaciones Forestales y Agropecuarias Bariloche. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; Argentina Fil: González Bulnes, Antonio. Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria; España Fil: Cueto, Marcela Isabel. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Estación Experimental Agropecuaria San Carlos de Bariloche. Instituto de Investigaciones Forestales y Agropecuarias Bariloche. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; Argentina

The present study compared the occurrence of oestrus behaviour and ovulation in response to the insertion of CIDR devices plus a classical treatment with equine chorionic gonadotrophin (eCG; single dose at CIDR removal) or alternative treatments with gonadotrophin-releasing hormone (GnRH, either in a single dose at 56 hr after CIDR removal, or in one dose at CIDR insertion and another dose at 56 hr after CIDR removal). The appearance of oestrus behaviour during reproductive season ranged between 84% and 95% and all females showing oestrus signs had subsequent ovulations. The response, during seasonal anoestrus, was similar in the group treated with eCG, but less than half of the females in the groups treated with GnRH showed oestrus signs in response to the treatment, although more than 80% of them showed resumption of ovulatory activity after the treatment. In conclusion, protocols based on GnRH administration offer similar yields to eCG-based protocols during the reproductive season but occurrence of oestrus in response to GnRH-based treatments is highly compromised during seasonal anoestrus.

The present review aims to offer a non-comprehensive outline of the current state-of-the-art and future perspectives on management and therapeutic tools for intrauterine growth restriction (IUGR) and associated prenatal programming in both human and animal species. Animals are used as models for the study of phenomena related to IUGR, but also for research on prenatal therapies with the main objective of designing and developing preventive and therapeutic strategies. The research is currently paying attention on maternal-focused pharmacological treatments and nutritional strategies but also on fetal-focused treatments. Fetal-focused treatments, administered either directly at the fetus or by using infusion of umbilical cord, amniotic sac or placenta, which avoids the administration of substances at high doses to the mother for allowing their availability at the fetoplacental level. The results obtained in this area of research using large animals (rabbits, pigs and ruminants) have a dual interest, for translational biomedicine and for veterinary medicine and animal production.

Simple Summary The current work evaluated the relative effects of the number of piglets in the litter of origin (high vs. low litter size) and the birthweight (low (LBW) vs. normal (NBW) in large litters) on postnatal performance and quality of carcasses and meat in purebred Iberian pigs. The results indicated that NBW piglets born in large litters had disparities in developmental patterns in weight and size, back-fat deposition, and fatty acid composition of viscerae compared to NBW piglets from small litters, which again were different from those found in LBW piglets when compared to their NBW counterparts. However, both growth patterns were altered and might indicate previous phases of metabolic disorders. Abstract Fatty pigs are characterized by a thrifty genotype, adapted to harsh environments based on changes in metabolism and energy saving. Thus, we hypothesized that feto-maternal energy partitioning in large litters might have postnatal effects that might be independent of intrauterine growth restriction (IUGR) processes. Hence, the current work reported the influence of two effects on postnatal performance and carcass and meat quality of purebred Iberian pigs: (a) the effects of the number of piglets in the litter (high vs. low litter size), and (b) the effects of birthweight (low (LBW) vs. normal (NBW)) in large litters. The results confirmed that NBW piglets born in large litters had differences in developmental patterns of weight, back-fat deposition, and fatty acid (FA) composition when compared to NBW piglets from small litters. These results were different from those found in LBW piglets when compared to their NBW counterparts, which showed an initial asymmetrical growth and altered muscle FA composition at slaughtering. The assessment of FA composition indicated better metabolic status in NBW piglets from large litters than in LBW piglets. These data support the concept that the prenatal environment, even when the individual may cope with it, inescapably affects postnatal life.

Additional file 1: Figure 1. – Concentrations-time data of the analysed metabolites and hormones on day 3 of phase 1. Asterisks indicate significant differences between M100 group and other groups (P

Fetal hypoxia, resulting in oxidative stress in pregnancies, contributes to reduced fetal growth. Melatonin, a potent antioxidant, has been associated with improved oxidative status. Maternal oral melatonin supplementation in sheep from day 50 of gestation ameliorates the consequences of fetal growth restriction in sheep. In rats, melatonin supplementation increases fetal weight via improved placental efficiency and reduction of oxidative stress. The objective of this study was to evaluate whether melatonin supplementation of single (S)- or twin-bearing (T) ewes using either 0 (0MEL), 1 (18-mg MEL), or 2 (36-mg MEL) slow release 18-mg melatonin implants (Regulin) from 100 to 140 d of pregnancy (n = 8 per group) influenced fetal oxygen supply and fetal weight. Fetal umbilical vein blood samples were collected at P140 and partial pressure of oxygen (PO2) and hemoglobin saturation by oxygen (SatHb) measured. The placenta from each fetus was excised and placentomes individually weighed and typed (A-D). Pregnancy rank, sex of the fetus, number of implants, and their interaction on fetal weight, blood gases, and placentome weight were analyzed using ANOVA. A 22% and 14% increase (P < 0.05) in body weight was obtained in 36- and 18-mg MEL compared with 0 MEL twin male fetuses, respectively, but no treatment effects were observed in singletons or females from twin pregnancies. Fetuses from ewes receiving 36-mg MEL had an 18% to 20% increase in cord PO2 (P < 0.05) compared with 18-mg MEL and 0MEL fetuses, which in turn did not differ. Fetal weight was positively correlated with PO2 (r = 0.37; P = 0.02), SatHb (r = 0.26; P = 0.03), and O2 content (r = 0.236; P = 0.048). No treatment effect on placentome average weight, total placentome weight per fetus or per ewe, nor total number of placentomes per fetus was observed. However, placentae from 36-mg MEL fetuses had a greater proportion of Type C (P < 0.05) than 0MEL and 18-mg MEL ewes, and tended to have a lower proportion of Type A (P = 0.1) and a greater proportion of Type D (P = 0.06) placentomes, compared with 0MEL ewes. These results indicate that maternal melatonin implants, independently of sex, improve oxygen supply to the fetus, which could potentially improve lamb vigor at birth. In addition, melatonin can increase fetal weight of twin males, by improving placental adaptation and fetal blood oxygenation.

Intrauterine growth restriction (IUGR) affects approximately 10% of human pregnancies globally and has immediate and life-long consequences for offspring health. However, the mechanisms underlying the pathogenesis of IUGR and its association with later health and disease outcomes are poorly understood. To address these knowledge gaps, the use of experimental animals is critically important. Since the 50's different environmental, pharmacological, and surgical manipulations have been performed in the rabbit to improve our knowledge of the control of fetal growth, fetal responses to IUGR, and mechanisms by which offspring may be programmed by an adverse gestational environment. The purpose of this review is therefore to summarize the utility of the rabbit as a model for IUGR research. It first summarizes the knowledge of prenatal and postnatal development in the rabbit and how these events relate to developmental milestones in humans. It then describes the methods used to induce IUGR in rabbits and the knowledge gained about the mechanisms determining prenatal and postnatal outcomes of the offspring. Finally, it discusses the application of state of the art approaches in the rabbit, including high-resolution ultrasound, magnetic resonance imaging, and gene targeting, to gain a deeper integrative understanding of the physiological and molecular events governing the development of IUGR. Overall, we hope to engage and inspire investigators to employ the rabbit as a model organism when studying pregnancy physiology so that we may advance our understanding of mechanisms underlying IUGR and its consequences in humans and other mammalian species.

Ovine reproduction efficiency in herds at high altitude (ha) is lower than that at low altitude (la). In ewes, ha effects are due to hypoxia and oxidative stress. Our aim was to establish the effect of antioxidant vitamin supplementation on semen traits and antioxidant status of rams exposed to short or long time ha. A total of 32 rams native to la (~500 m) were used, 16 were kept at la and the other 16 were brought to ha (~3600 m), where they were placed in the same flock as the ha native rams (n=16). Half of the animals in each group were supplemented daily with vitamins C 600 mg and E 450 IU per os, during the entire experimental period, starting the 4th day after animal’s arrival at ha (day 0). At days 0, 30 and 60 of treatment, blood and semen samples were collected for evaluation of antioxidant status and semen standard characteristics. Data were compared within each experimental time by analysis of variance using a general linear model. Elevated concentrations of oxidative stress biomarkers were present in blood from animals maintained at ha. Ejaculates from ha exposed rams showed decreased sperm concentration, progressive motility and viability, in addition to decreased antioxidant status in seminal fluid. A total of 30 days of oral supplementation with vitamins C and E prevented some ha negative effects on semen characteristics, mainly in recently ha exposed rams. It is concluded that exposure of rams to ha negatively affects semen quality, where oxidative stress plays a predominant role. These effects are mainly prevented by oral supplementation of vitamins C and E, which constitutes a simple and cheap alternative to improve semen quality of rams when they are moved to ha.

This study assessed milk productivity, demographic characteristics and workload distribution on a single high-yield dairy ewe farm in Spain (Avila, Spain; continental climate, latitude of 40.90 N, altitude of 900 m) over a 7-year period considering a transition from a herd management system involving five lambings per year (5LY) to a system involving 10 lambings per year (10LY). The 5LY system was practiced on the farm from 2010 to 2012 and the 10LY system from 2014 to 2015, with 2009 and 2013 being considered transition years. During this period, 27 415 lactations were recorded from an average of 3746 Lacaune sheep/year. Several productivity parameters were higher in 2014 to 2015 than in 2010 to 2012: milk yield/lactation (370±156 v. 349±185 l), lactation length (218±75 v. 192±75 days) and dry period length (53.5±38.3 v. 69.1±34.8 days) (all P

The aim of the present study was to evaluate the productive, endocrine, and metabolic responses as well as oxidative stress of rabbit does and their offspring when fed a diet supplemented with n -3 PUFA during their first productive cycle. To this aim, a total of 105 rabbit does were fed ad libitum from d 60 to 172 of age 2 isoenergetic and isoproteic diets dif - fering in fatty acid composition. The control diet ( n = 52 does) contained 45.9 g/kg of n -3 of the total fatty acids and the enriched diet ( n = 53 does) contained 149.2 g/kg of n -3 of the total fatty acids. Both experi - mental groups had similar feed intake during rearing, pregnancy, and lactation. The enrichment of diet had no effect on ultrasonographic assessment of does on d 9 and 16 of pregnancy, with an embryonic vesicle number and fetus and placenta size similar between groups ( P > 0.05). Even though there were no major effects ( P > 0.05) on fertility, duration of gestation, and number born alive and stillborn kits at parturition, live kits from enriched does were longer (71.6 ± 2.42 vs. 79.5 ± 2.13 mm; P 0.05). In enriched does, higher plasma leptin and estradiol concentrations than in control does ( P < 0.05) were observed. In addition, enriched females also had lower total and high-density lipoprotein cho - lesterol (HDL-c) than control females during lactation ( P < 0.05). Regarding offspring, the enrichment of diet with PUFA caused a hyperlipidemic status (greater values of plasma triglycerides, total cholesterol, and HDL-c; P < 0.05) at 1 d postpartum (dpp), compared with the control group, that disappeared at 32 dpp. Supplemented does before parturition and their off - spring at 1 dpp had greater oxidative stress than those in the control group. In conclusion, an increase of n -3 PUFA concentration in the diet of rabbit does and, consequently, of their offspring during a productive cycle alters their lipid profile and the indicators of oxi - dative stress, without major endocrine modifications or improvements in the productive variables.

El presente artículo revisa diversos aspectos de la programación prenatal en el cerdo ibérico. La investigación sobre los factores que condicionan el fenotipo adulto y la homeorresis en diferentes especies ha abordado tanto la predisposición genética como el papel determinante de la nutrición durante el período prenatal. Tanto la sobrenutrición como la subnutrición en la etapa fetal (la segunda por subnutrición materna o por insuficiencia placentaria) pueden alterar la expresión del genoma y los componentes y funciones de los diferentes sistemas en la descendencia, lo que da lugar a alteraciones en el desarrollo y composición corporal, aparición de trastornos metabólicos y un mayor riesgo para la salud. En los cerdos, y específicamente en la raza ibérica, la exposición de los fetos a la sub/desnutrición, comúnmente por desnutrición materna o insuficiencia placentaria, tiene una alta incidencia en fases avanzadas de gestación. Los lechones expuestos a desnutrición materna durante los dos últimos tercios de la gestación son más pequeños al nacer, ya que se ven afectados por un proceso denominado ‘retraso del crecimiento intrauterino’ o IUGR por sus siglas en inglés. En razas magras, tanto los machos como las hembras ven comprometido su crecimiento postnatal y se produce un aumento de la acumulación de grasa y aparición de trastornos metabólicos durante los períodos de engorde. En la raza ibérica, el crecimiento postnatal en el caso de la exposición prenatal a dietas de baja energía depende del sexo. Así, el crecimiento postnatal en los machos se ve afectado de forma similar a las razas magras, mientras que sus hermanas muestran un crecimiento compensatorio muy temprano, durante el período de lactación, antes del destete. Posteriormente, en respuesta a las dietas con alto contenido energético que se utilizan durante el período de engorde, tanto los machos como las hembras presentan aumento de adiposidad a nivel subcutáneo, visceral e intramuscular, presentan una mayor incidencia de trastornos metabólicos y presentan cambios significativos en la composición intramuscular de ácidos grasos, con respecto a los lechones que no habían sufrido subnutrición durante su vida intrauterina.

Este artículo se encuentra disponible en la página web de la revista en la siguiente URL: https://onlinelibrary.wiley.com/doi/abs/10.1111/rda.13537 This is the pre-peer reviewed version of the following article: Uriol, M., Martinez-Ros, P., Rios, A., Encinas, T. & Gonzalez-Bulnes, A. (2019). Onset of oestrus and periovulatory events in sheep exposed to 5 and 14 days of CIDR treatment with and without eCG. Reproduction in Domestic Animals, vol. 54, i. 11, pp. 1489-1492, which has been published in final form at https://doi.org/10.1111/rda.13537. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. Este es el pre-print del siguiente artículo: Uriol, M., Martinez-Ros, P., Rios, A., Encinas, T. & Gonzalez-Bulnes, A. (2019). Onset of oestrus and periovulatory events in sheep exposed to 5 and 14 days of CIDR treatment with and without eCG. Reproduction in Domestic Animals, vol. 54, i. 11, pp. 1489-1492 que se ha publicado de forma definitiva en https://doi.org/10.1111/rda.13537 The present study supports that 5-days short-term CIDR treatments without administration of eCG are equally effective for inducing estrus behavior, preovulatory LH discharge and ovulation in sheep than classical protocols based on 14-days treatments plus eCG at CIDR withdrawal. However, the implementation of a 5-days protocol without eCG for fixed-time artificial insemination would be adapted to a later timing of ovulation (p < 0.05).

Este artículo se encuentra disponible en la siguiente URL: https://www.tandfonline.com/doi/full/10.1080/09712119.2019.1599899 The present study indicates that short-term progestagen-based protocols for synchronization of estrus and ovulation in sheep involving 7 days of progestagen insertion with administration of prostaglandin F2α at either insertion or removal of the progestagen sponge resulted in 80–90% fertility during the breeding season, while a classical long-term protocol of 14 days of progestagen insertion resulted in 77% fertility. During the non-breeding season, fertility was significantly higher for the 7-day protocol with prostaglandin administration at sponge insertion (79.2%) and for the 14-day protocol (80%) than for the 7-day protocol with prostaglandin administration at sponge removal (59.1%; P = 0.018). Prolificacy, in contrast, varied significantly with genotype, being higher in prolific breeds, but it did not vary with progestagen protocol or breeding season. These results suggest that short-term progestagen-based treatments can provide similar reproductive efficiency as long-term treatments, which may help practitioners reduce welfare and health issues while maintaining productivity.

The current study aimed to determine, using a swine model of intrauterine growth restriction (IUGR), whether short- and long-term neurological deficiencies and interactive dysfunctions of Low Birth-Weight (LBW) offspring might be related to altered pattern of neurotransmitters. Hence, we compared the quantities of different neurotransmitters (catecholamines and indoleamines), which were determined by HPLC, at brain structures related to the limbic system (hippocampus and amygdala) in 14 LBW and 10 Normal Body-Weight (NBW) newborn piglets. The results showed, firstly, significant effects of sex on the NBW newborns, with females having higher dopamine (DA) concentrations than males. The IUGR processes affected DA metabolism, with LBW piglets having lower concentrations of noradrenaline at the hippocampus and higher concentrations of the DA metabolites, homovanillic acid (HVA), at both the hippocampus and the amygdala than NBW neonates. The effects of IUGR were modulated by sex; there were no significant differences between LBW and NBW females, but LBW males had higher HVA concentration at the amygdala and higher concentration of 5-hydroxyindoleacetic acid, the serotonin metabolite, at the hippocampus than NBW males. In conclusion, the present study shows that IUGR is mainly related to changes, modulated by sex, in the concentrations of catecholamine neurotransmitters, which are related to adaptation to physical activity and to essential cognitive functions such as learning, memory, reward-motivated behavior and stress. © 2016 ISDN

Este artículo se encuentra disponible en la siguiente URL: https://www.mdpi.com/2076-3921/9/10/1023 Este artículo pertenece al número especial "Antioxidants in Veterinary medicine". Reproduction is a complex process that is substantially a ected by environmental cues, specifically feed/diet and its components. Farm animals as herbivorous animals are exposed to a large amount of polyphenols present in their natural feeding system, in alternative feed resources (shrubs, trees, and agro-industrial byproducts), and in polyphenol-enriched additives. Such exposure has increased because of the well-known antioxidant properties of polyphenols. However, to date, the argumentation around the impacts of polyphenols on reproductive events is debatable. Accordingly, the intensive inclusion of polyphenols in the diets of breeding animals and in media for assisted reproductive techniques needs further investigation, avoiding any source of reproductive waste and achieving maximum benefits. This review illustrates recent findings connecting dietary polyphenols consumption from di erent sources (conventional and unconventional feeds) with the reproductive performance of farm animals, underpinned by the findings of in vitro studies in this field. This update will help in formulating proper diets, optimizing the introduction of new plant species, and feed additives for improving reproductive function, avoiding possible reproductive wastes and maximizing possible benefits.

Este artículo se encuentra disponible en la página web de la revista en la siguiente URL: https://www.publish.csiro.au/rd/RD18477 This is the pre-peer reviewed version of the following article: Gonzalez-Bulnes, A., Menchaca, A., Martin, G.B. & Martinez-Ros, P. (2020). Seventy years of progestagen treatments for management of the sheep oestrous cycle: where we are and where we should go. Reproduction, Fertility and Development, vol. 32, i. 5 (24 jan.), pp. 441-452, which has been published in final form at https://doi.org/10.1071/RD18477. Este es el pre-print del siguiente artículo: Gonzalez-Bulnes, A., Menchaca, A., Martin, G.B. & Martinez-Ros, P. (2020). Seventy years of progestagen treatments for management of the sheep oestrous cycle: where we are and where we should go. Reproduction, Fertility and Development, vol. 32, i. 5 (24 jan.), pp. 441-452, que se ha publicado de forma definitiva en https://doi.org/10.1071/RD18477. The management of the ovine estrous cycle is mainly based on the use of exogenous hormones for mimicking (progesterone and its analogues) or manipulating (prostaglandin F2α and its analogues) the activity of the corpus luteum, combined with the application of other hormones mimicking the pituitary secretion of gonadotrophins (e.g.: equine chorionic gonadotrophin, eCG). These protocols have been applied without major change for decades but, now, there are two reasons to reconsider them: i) our greatly improved knowledge of the dynamics of ovarian physiology, following the application of transrectal ultrasonography, indicates that modification of the protocols may improve the yields; ii) increasing concerns about animal health and welfare, food safety and the environmental impact of the treatments, as evidenced by public opinion and therefore market forces. Here, we offer an overview of these issues, introduce an updated protocol, and suggest ways for future improvements of the protocols. Preprint

This study aimed to determine the effects of piglet birthweight (BIW) and sex, and within-litter BIW variation, on postnatal growth traits and meat quality in fatty breeds of pig. In total, 406 crossbred piglets (half male, half female) born to Iberian sows were studied during their postnatal development until slaughter. After birth, piglets were classified into four BIW categories: very low, low, medium and high. There was a negative effect of low BIW on growth patterns and fatty acid (FA) composition, but effects of litter size and within-litter BIW variation were not found. The very low BIW piglets underwent a period of significant catch-up growth (P < 0.005) relative to high BIW piglets during the early postnatal phase, but also showed a higher feed conversion rate and lower average daily weight gain (P < 0.05 for both measures) throughout the study period. BIW affected development during the entire productive life, and the sex effect increased with age. As a result, the period to reach market weight was longer in very low BIW piglets, by 43 days for females and 15 days for males, compared with their high BIW counterparts. BIW and sex also influenced amount of intramuscular fat, n-3 FA content and monounsaturated FA composition. The study indicates that BIW, modulated by sex, is a critical point for productive traits in fatty pigs. These results provide a basis for future strategies to enhance productive efficiency and meat quality of traditional swine breeds.

The present study characterizes, for sheep, the occurrence and timing of the onset of estrus behavior and ovulation and the yields obtained (ovulation rate, progesterone secretion, and fertility) after Controlled Internal Drug Release (CIDR) insertion for five, six, seven, or fourteen days, with or without equine chorionic gonadotrophin (eCG) in ewes of the Segure&ntilde, a meat breed. All the treatments showed above 80% of females displaying estrus, but the onset of estrus was earlier and more synchronized when using eCG and, among groups with eCG, onset of estrus was earlier in the sheep treated for 14 days than in the short-term treatments (p &lt, 0.05 for all). Administration of eCG after either short- or long-term treatments assured the occurrence of fertile ovulations in all the animals. Conversely, ovulatory success without eCG was found to be dependent on treatment length, with a high percentage of animals ovulating after five days of treatment (83.3%) and very low percentages after treatment for six or seven days (40% and 20%, respectively). Ovulation rate and progesterone secretion were similar among animals ovulating, but ovulation failures predetermined the fertility yields obtained in response to the treatments. Hence, the best results were found after treatment for 14 days plus eCG, and for 5 days without eCG (83.3 for both, p &lt, 0.05 when compared to the other groups with different treatment lengths and with or without eCG).

The aim of this study was to investigate the blood concentrations of L-arginine, asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA), and L-homoarginine, which are regulators of nitric oxide (NO) synthesis, in single, twin, and triplet pregnancies in ewes undergoing either a dietary energy restriction or receiving 100% of their energy requirements. From day 24 to 100 of pregnancy, the ewes were fed ryegrass hay and two different iso-proteic concentrates fulfilling either 100% of ewes&rsquo, energy requirements (control group, n = 30, 14 singleton pregnancies, 12 twin pregnancies, and 4 triplet pregnancies) or only 45% (feed-restricted group, n = 29, 11 singleton pregnancies, 15 twin pregnancies, and 3 triplet pregnancies). Blood samples were collected monthly to measure, by capillary electrophoresis, the circulating concentrations of arginine, ADMA, homoarginine, SDMA, and of other amino acids not involved in NO synthesis to rule out possible direct effects of diet restriction on their concentrations. No differences between groups were observed in the circulating concentrations of most of the amino acids investigated. L-homoarginine increased markedly in both groups during pregnancy (p &lt, 0.001). SDMA (p &lt, 0.01), L-arginine, and ADMA concentrations were higher in feed-restricted ewes than in controls. The L-arginine/ADMA ratio, an indicator of NO production by NOS, decreased towards term without differences between groups. The ADMA/SDMA ratio, an index of the ADMA degrading enzyme activity, was higher in controls than in feed-restricted ewes (p &lt, 0.001). Obtained results show that circulating concentrations of L-arginine, of its metabolites, and the ratio between NO synthesis boosters and inhibitors are altered in energy-restricted ewes, and that these alterations are more marked in ewes carrying multiple fetuses.

In the last decades small ruminants have become increasingly important, and nowadays sheep and goat are continuously increasing in the number of breeds and their geographic distribution. An important feature of small ruminants is that they can live and produce on land that is unfavorable for other forms of agriculture. The increase in small ruminant breeding has been supported more recently by the development and improvement of assisted reproductive technologies (ARTs). However, while some ARTs have reached widespread application, including estrus induction, estrus synchronization, and artificial insemination, other ARTs, such as superovulation and embryo transfer, in vitro embryo production, and embryo cryopreservation, are only rarely used. Multiple ovulation and embryo transfer (MOET) programs in small ruminants are usually restricted to few countries and still remain experimental. The success of this technique is unpredictable due to many limiting factors that contribute to the overall results, such as the reproductive seasonality with a long, naturally occurring anestrus period, high variability of the superovulatory response, fertilization failures, and the need of surgery for collection and transfer of gametes and embryos. However recent progress in better understanding of the follicular wave patterns, the elucidation of follicular dominance, and the integration of this information into superovulation treatments are instrumental in predicting good responders and reducing variability. Protocols that control follicular dominance have been developed to allow the initiation of precise hyperstimulation protocols which are designed to recruit and stimulate a homogeneous pool of small follicles that are gonadotrophin responsive, thereby enhancing superovulatory response and embryo yields. Significant improvements in the development of nonsurgical techniques are paving the way to reducing stress and costs of donors and recipient management, indicating the possible repeated use of individual donors. In addition, the progress with IVP embryos generated from adult and juvenile animals, combined with the genomic analysis of economically productive tracts, is opening new perspectives and could be instrumental for improving MOET programs in small ruminants.

The critical role of intrauterine environment on pregnancy development, newborn features and postnatal life is currently well-known. Alterations in the supply of nutrients and oxygen to the fetus, either of maternal or placental origin, modify development and metabolic traits of the offspring with lifespan consequences. Hence, the enhancement of placental development and function, in addition with adequate maternal nutrition and lifestyle and especially the improvement of the antioxidant defense system and oxidative stress at the fetoplacental unit through maternal supplementation with antioxidants, is a main target. Polyphenols are potent antioxidants (but also metabolism-regulatory, antiinflammatory and immunomodulatory agents) present at high concentrations in natural foods and beverages. Polyphenols are perceived as beneficial for pregnancy in spite of a scarcity of objective data on both realistic benefits and potential hazards. Hence, the present review summarizes the available information in the field.

The present study used a sheep model of intrauterine growth restriction, combining maternal undernutrition and twinning, to determine possible markers of early damage to the fetal kidney. The occurrence of early deviations in fetal hemodynamics which may be indicative of changes in blood perfusion was assessed by Doppler ultrasonography. A total of 24 sheep divided in two groups were fed with the same standard grain-based diet but fulfilling either their daily maintenance requirements for pregnancy (control group; n=12, six singleton and six twin pregnancies) or only the 50% of such quantity (food-restricted group; n=12; four singleton and eight twin pregnancies). All the fetuses were assessed by both B-mode and Doppler ultrasonography at Day 115 of pregnancy. Fetal blood supply was affected by maternal undernutrition, although there were still no evidences of brain-sparing excepting in fetuses at greatest challenge (twins in underfed pregnancies). However, there were early changes in the blood supply to the kidneys of underfed fetuses and underfed twins evidenced decreases in kidney size.

Background Bovine respiratory disease (BRD) is one of the leading causes of economic losses in the beef and dairy industry. Reliable antemortem tools for diagnosing BRD would improve the efficacy of treatment and reduce costs. Here we examined whether the relatively simple technique of thoracoscopy can support BRD diagnosis under field conditions. We also compared various equipment set-ups in order to optimize the safety and efficacy of the procedure. A total of 24 thoracoscopic procedures were performed in 17 calves diagnosed with BRD and in 2 healthy control calves. Rigid and flexible endoscopes and industrial videoscopes were tested using various insertion approaches. The suitability of the technique was assessed in terms of duration, volume of air extracted, visualization score, and image quality. Safety was assessed in terms of rectal temperature, body weight, breaths/min, presence of fibrinogen, pain score, recovery time, intraoperative complications and risk of laceration or threatening collapse. Results Insertion of a flexible endoscope via a right, dorso-caudal approach at the 5th intercostal space allowed complete examination of the right lung in 15 min, as well as identification of main lung lesions and adherences in calves with BRD, without compromising calf welfare. While the dorso-caudal approach was optimal, it was associated with substantial discomfort when rigid endoscopes were used, minimal complications or mortality due to thoracoscopy were observed up to 28 days after the procedure. Videoscopes were as safe and easy to use as endoscopes, but endoscopes provided better image quality. Conclusion This study provides the first field evidence that thoracoscopy can be safe to explore BRD-diseased calves. These results justify a larger study to rigorously assess the diagnostic performance of the technique.

The present study evaluated the effectiveness of sildenafil citrate (SC) to improve placental and fetal growth in a diet-induced rabbit model of intrauterine growth restriction (IUGR). Pregnant rabbits were fed either ad libitum (Group C) or restricted to 50% of dietary requirements (Group R) or restricted and treated with SC (Group SC). The treatment with SC improved placental development by increasing vascularity and vessel hypertrophy in the decidua. The assessment of feto–placental haemodynamics showed higher resistance and pulsatility indices at the middle cerebral artery (MCA) in fetuses treated with SC when compared with Group R, which had increased systolic peak and time-averaged mean velocities at the MCA. Furthermore, fetuses in the SC group had significantly higher biparietal and thoracic diameters and longer crown–rump lengths than fetuses in Group R. Hence, the SC group had a reduced IUGR rate and a higher kit size at birth compared with Group R. In conclusion, SC may provide potential benefits in pregnancies with placental insufficiency and IUGR, partially counteracting the negative effects of food restriction on placental development and fetal growth. However, the present study also found evidence of a possible blood overflow in the brain that warrants further investigation.

Sex-related differences in lipid availability and fatty acid composition during swine foetal development were investigated. Plasma cholesterol and triglyceride concentrations in the mother were strongly related to the adequacy or inadequacy of foetal development and concomitant activation of protective growth in some organs (brain, heart, liver and spleen). Cholesterol and triglyceride availability was similar in male and female offspring, but female foetuses showed evidence of higher placental transfer of essential fatty acids and synthesis of non-essential fatty acids in muscle and liver. These sex-related differences affected primarily the neutral lipid fraction (triglycerides), which may lead to sex-related postnatal differences in energy partitioning. These results illustrate the strong influence of the maternal lipid profile on foetal development and homeorhesis, and they confirm and extend previous reports that female offspring show better adaptive responses to maternal malnutrition than male offspring. These findings may help guide dietary interventions to ensure adequate fatty acid availability for postnatal development. © 2017 by the authors. Licensee MDPI, Basel, Switzerland.

Previous results obtained in gilts maintained under experimental conditions suggest that amino acid supplementation during pregnancy may be a promising strategy for diminishing the incidence of embryo losses and low birth-weight newborn. The current study evaluated the effects of a short-term supplementation with L-proline, around implantational stages, on litter size and birth-weight of piglets in sows of different parities maintained under commercial farm conditions. There were no significant effects in mature sows with three or more parities, but the supplementation improved the reproductive efficiency of the high-prolific first-parity sows and of all the sows at second-parity. There were numerically higher litter size (of around two more live piglets; n.s.) and higher birth-weights (P

Purposes To determine the feasibility of MRI for imaging subcutaneous and visceral adiposity in longitudinal studies in obese swine models (Iberian pig). To establish the anatomical regions of interest (ROIs) and measurement points (MPs) adequate for their evaluation through analyses on the inter-individual variability and over-time reproducibility and through the assessment of their reliability and validity by comparison with in vivo and ex vivo zoometric data. Material and methods Five male and five female pigs were used from four (live weight around 48 kg and back-fat depth around 18 mm) to eight months old (live weight 134 kg and back-fat depth around 48 mm). MRI was carried out with a Panorama 0.23T scanner (Philips Medical Systems, Best, Netherlands), using a body/spine XL coil. Results The ROIs of election for visualization of subcutaneous data are located from the cranial margin of left diaphragmatic crura to the lumbar vertebrae L3. Visceral adiposity may be equally evaluated from the vertebrae L1 to L3. Conclusions MRI allows the evaluation of subcutaneous and visceral fatness in a single acquisition, which improves animal welfare and time- and cost-efficiency and provides an accurate, consistent and repeatable procedure for sequential studies of adiposity in obese swine. © 2014 Éditions françaises de radiologie. Published by Elsevier Masson SAS. All rights reserved.

New Findings What is the central question of this study? What is the effect of prepuberal metformin therapy and lifestyle in an obese swine model (Iberian gilts) with thrifty genotype on patterns of growth, fattening, metabolic status and attainment of puberty? What is the main finding and its importance? An obesogenic diet had deleterious effects on corpulence, adiposity and metabolic parameters. These features were favourably modulated by adequate lifestyle and metformin treatment, which favoured muscle deposition. However, metformin advanced the onset of puberty, which would be a negative effect. This provides a warning about the use of metformin, without further studies, in girls from ethnicities with thrifty genotype. The prevention and treatment of obesity in children is based on adequate nutrition and exercise plus antihyperglycaemic drugs. Currently, the incidence of childhood obesity is aggravated in ethnicities with thrifty genotype, but there is no available information on the effects of metformin therapy. The relative effects of lifestyle and metformin on patterns of growth, fattening, metabolic status and attainment of puberty were assessed in females of an obese swine model (Iberian gilts), allocated to three experimental groups (group A, obesogenic diet and scarce exercise; group DE, adequate diet and opportunity for exercise; and group DEM, adequate diet and opportunity for exercise plus metformin). Group A evidenced high weight, corpulence and adiposity, high plasma triglycerides and impairments of glucose regulation predisposing to insulin resistance. These features were favourably modulated by adequate lifestyle (group DE), and these effects were strengthened by metformin treatment (group DEM), which induced an improvement in body development by favouring muscle deposition. However, contrary to expectations, metformin advanced the onset of puberty. Metformin treatments would have positive effects on growth patterns, adiposity and metabolic features of young females from ethnicities with thrifty genotype or developing leptin resistance, but a negative effect by advancing the attainment of puberty. This study provides a warning regarding the use of metformin, without further studies, in girls from these ethnicities.

Resume Objectifs Determiner la faisabilite de l’IRM pour la realisation d’imageries de la graisse sous-cutanee et viscerale au cours d’etudes longitudinales sur des modeles porcins d’obesite (porc iberique) in vivo. Etablir les regions d’interet (RDI) anatomiques et les points de mesure (PM) adequats afin de les evaluer par des analyses portant sur la variabilite inter-individuelle et leur reproductibilite au cours du temps et par l’evaluation de leur fiabilite et de leur validite par rapport a des donnees zoometriques in vivo et ex vivo. Materiels et methodes Cinq porcs mâles et cinq porcs femelles âges de quatre a huit mois ont ete utilises. L’IRM a ete effectuee avec un appareil Panorama de 0,23 T (Philips Medical Systems, Best, Pays-Bas), en utilisant une antenne corps/rachis XL ( body/spine XL coil ). Resultats Les RDI de choix pour la visualisation des donnees sous-cutanees sont situees entre le bord cranial du pilier gauche du diaphragme et la vertebre lombaire L3. L’adiposite viscerale peut egalement etre evaluee des vertebres L1 a L3. Conclusions L’IRM permet l’evaluation de la graisse sous-cutane et viscerale lors d’une seule acquisition, ce qui ameliore le bien-etre animal ainsi que les rapports temps–efficacite et cout–efficacite, et permet de realiser une procedure precise, coherente et repetable pour des etudes ulterieures de l’adiposite chez des porcs obeses.

Intrauterine growth restriction (IUGR) is characterized by reduced growth and weight of the foetus, mainly due to the lack of nutrients and oxygen. Animals affected by IUGR show changes in specific brain areas and several neuronal processes. Female offspring affected by IUGR show increased survival and development compared to males. The objective of this study was to analyse changes in the hippocampus proteome in male and female piglets affected by IUGR. Seven pregnant Iberian sows were fed from Day 35 of pregnancy onwards at 50% of their requirements. At Day 100 of pregnancy, foetuses were obtained and classified by sex and weight, as mild IUGR (Normal Body Weight) versus severe IUGR (Low Body Weight). Hippocampi were dissected and the proteomes analysed by SWATH-MS DIA. In this study, 1497 proteins were identified of which 260 were quantitatively analysed. All differential proteins were more abundant in females versus males and were involved in protein synthesis, neuronal development, metabolism, antiapoptotic signalling and vesicular transport. Our findings support that female foetuses tolerate nutrient limitation better than males, especially under mild IUGR. Under severe IUGR, females still seems to maintain normal lipid metabolism and antiapoptotic signalling, which may be related to the increased female survival. SIGNIFICANCE: In the last years, proteomics have been used to evidence differences related to sex in non-reproductive organs. Intrauterine Growth Restriction (IUGR) can affect female and male offspring differently. Female offspring has stronger protective strategies compared to males, enhancing growth and postnatal survival. Most studies regarding this issue have focused on metabolic organs (i.e. liver). However, the predominance of neurodevelopmental disorders in males suggests that the central nervous system in female offspring adapt better to nutritional stress conditions than that of males. Based on the differential protein expression in hippocampal samples, our work demonstrates that female foetuses indeed adapt better to IUGR than males, especially under mild IUGR conditions. In severe IUGR conditions, differences between males and females were not so evident, but even in this case, the remaining differences suggest increased survival in females than in males.