This study evaluated the effects of maternal supplementation with rumen-protected methionine (RPM), alone or combined with rumen-protected choline (RPC) and betaine (RPB), during the periconceptional and prepartum periods on reproductive outcomes and offspring performance in Chios ewes. One hundred synchronized ewes were assigned to three groups—control (no supplementation), M (5.50 g RPM/day), and MCB (3.50 g RPM, 1.60 g RPC, 0.49 g RPB/day)—from day −14 to +14 relative to mating. Blood was collected on days −14, 0, and +14 for ABTS (2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid), ferric-reducing ability (FRAP), and malondialdehyde (MDA), on days 18 and 21 for progesterone, and on day 26 for pregnancy-associated glycoprotein (PAG) detection. Thirty days before and up to lambing, the ewes were further divided into C-C, C-M, C-MCB, M-M, M-C, MCB-MCB, and MCB-C subgroups. Embryonic loss did not differ between groups. FRAP was higher (p < 0.001) in MCB ewes, and ABTS was lower (p < 0.05) in M ewes, in the periconceptional period. Offspring in the C-M, C-MCB, M-M, M-C, and MCB-MCB groups had higher birth weights (p < 0.01), along with increased MDA levels (p < 0.05). The results suggest that maternal methyl donor supplementation during early and/or late gestation enhances antioxidant status, supports embryonic development, and increases birth weight.

Dairy ruminants provide a major part of the livestock and agriculture sectors. Due to the increase in world population and the subsequent increase in dairy product demands, the dairy sector has been intensified. Dairy farming intensification and the subsequent increase in animal nutritional demands and the increase in the average global temperature as well have subjected animals to various stress conditions that impact their health and welfare. Various management practices and nutritional strategies have been proposed and studied to alleviate these impacts, especially under heat stress, as well as during critical periods, like the transition period. Some of the nutritional interventions to cope with stress factors and ensure optimal health and production are the inclusion of functional fatty acids and amino acids and feed additives (minerals, prebiotics, probiotics, essential oils and herbs, phytobiotics, enzymes, etc.) that have been proven to regulate animals’ metabolism and improve their antioxidant status and immune function. Thus, these nutritional strategies could be the key to ensuring optimum growth, milk production, and reproduction efficiency. This review summarizes and highlights key nutritional approaches to support the remarkable metabolic adaptations ruminants are facing during the transition period and to reduce heat stress effects and evaluate their beneficial effects on animal physiology, performance, health, as well as welfare.

The preovulatory follicles and preimplantation stage embryos are found to be rather sensitive to heat stress due to their low potential for scavenging reactive oxygen species (ROS). The aim of the present study was to assess the impact of melatonin administration on redox status and hematological variables during the preovulatory period and early stages of embryogenesis in heat-stressed ewes in vivo. Forty Karagouniko-breed ewes were divided in two groups, the melatonin (M, n = 20) group and control (C, n = 20) one. All animals were subjected to heat stress throughout the study, which lasted forty days (D0 to D40). In M group, melatonin implants were administered on D0. Then, oestrous synchronization was applied (D19-D33). On D34, six rams were introduced into the ewe flock for mating. Ultrasonographic examination was conducted on D73 for pregnancy diagnosis. The temperature humidity index (THI), the rectal temperature (RT), and the number of breaths per minute (BR) were evaluated twice daily. Redox biomarkers, namely total antioxidant capacity (TAC), reduced glutathione (GSH), and thiobarbituric acid reactive substances (TBARS), were assayed in blood samples collected on D0, D33, and D40. In addition, packed cell volume (PCV), white blood cells (WBCs), leukocyte differential count, and cortisol assessment were conducted in blood samples on D33 and D40. The results indicated improved fertility rate and mean number of lambs born per ewe due to improved redox status (p < 0.05) in ewes that received melatonin implants 34 days approximately before the onset of oestrus. The PCV decreased in both groups between the two time-points (p < 0.05). However, the NEU/LYMPH ratio decreased (p < 0.05) only in group M. The low cortisol levels and the decreased NEU/LYMPH ratio in both groups support the hypothesis that ewes of the indigenous Karagouniko breed may exhibit adaptation to environmental thermal stress. The administration of melatonin as an antioxidant regime may improve the reproductive competence of heat stressed ewes and may also enhance their ability to adapt at high ambient temperatures.

In this study, the effects of melatonin treatment on growth, redox status and immunity in prenatally stressed newborn lambs were evaluated. Thirty-seven newborn lambs were allocated into two groups (melatonin-MEL and control-CON), based on whether their mothers were treated with melatonin implants or not, respectively. All pregnant ewes were exposed to heat stress. The body weight of lambs was recorded at birth (L0), and then on days 15 (L15) and 40 (L40). Redox biomarkers [total antioxidant capacity (TAC), glutathione (GSH), thiobarbituric acid reactive substances (TBARS)] were assayed in blood samples collected from lambs on days L0, L1, L2, L5, L10 and L40. Chemical analysis and antioxidant capacity were evaluated in colostrum and milk samples collected at the same time points with blood samples. Cytokines (IL-1β, IL-6, IL-10, IFN-γ) and immunoglobulin (IgG) were assayed in blood and colostrum samples collected from ewes on days L0 and L1, and in lambs' blood on days L0, L1 and L2. The results revealed that body weight gain of newborn lambs did not differ between the two groups (p > 0.05). Better redox status was found in MEL lambs until L2, as well as higher antioxidant capacity in the colostrum of MEL ewes compared to CON ones on day L0 (p < 0.05). In MEL ewes' colostrum, higher protein content was measured on day L0 and higher fat content on L1 compared to CON group (p < 0.05). The highest level of IL-6 was found in MEL ewes on L1, with a concomitant increase of IL-10 level in MEL lambs in comparison to CON lambs on L2. Moreover, CON colostrum resulted in a higher level of IL-10 within time, coupled with an increased level of IgG found in lambs' plasma on L2 (p = 0.04). This study indicated that melatonin could be administered as antioxidant and immune-modulatory regime in prenatally stressed offspring in order to cope with the crucial first days of their life. This effect of melatonin was also amplified by crosstalk between IL-6, IL-10 and IgG production, resulting in an improved quality of produced milk.

Selenium (Se) is an essential trace element of fundamental importance to health due to its antioxidant, anti-inflammatory, and chemopreventive properties, attributed to its presence within at least 25 selenoproteins (Sel). In this review, we describe some of the recent progress, in our understanding, on the impact of maternal Se intake during the periconceptional period on offspring development and health. Maternal nutrition affects the performance and health of the progeny, and both maternal and offspring Se supplementations are essential for the optimal health and antioxidant protection of the offspring. The case of Se in epigenetic programming and early life nutrition is also discussed.

Does are usually fed ad libitum during pregnancy, a fact that can result in intrauterine overfeeding and can have detrimental effects on embryonic programming with permanent changes in the physiology and behavior of the offspring. An experiment was therefore conducted to examine the effect of does' overfeeding during two different periods of pregnancy on the behavior of kits after weaning. Fifteen does were allocated into three groups: control (M) (100% of maintenance energy requirements [MER] throughout pregnancy), O1 (129% of MER between the 7th and 19th of pregnancy), and O2 (138% of MER between the 20th and 27th day of pregnancy). At the ages of 50 and 65 days, the behavior of 24 randomly selected rabbits in home cages was recorded for three consecutive days, while an open field test that constitutes a good indicator of locomotion score and stress was conducted for another 24 rabbits. Rabbits in O1 and O2 groups had more meals in shorter duration and moved and explored their environment less than the controls (P < 0.05). No significant effects on the exhibition of behavior were found during the open field test with the exception of rearing that was displayed more by the O1 and O2 rabbits. Comfort behaviors and resting had increased values, although frequency and duration of eating and drinking were significantly decreased at the age of 65 days (P < 0.05). Males had higher values for frequency of eating than the females (P < 0.01). We concluded that behavior of rabbits born from overnourished does was modified, with decreased values for locomotion and exploration. (C) 2019 Elsevier Inc. All rights reserved.

Τeτρακόσιοι νeοσσοί κρeοπαραγωγής, ηλικίας μιας ημέρας, χρησιμοποιήθηκαν για να μeλeτηθeί η eπίδραση του σeληνίου και της βιταμίνης E σe eπιλeγμένα σeληνιοένζυμα που σχeτίζονται μe τη λeιτουργία του θυροeιδούς αδένα. Υπήρχαν τέσσeρις διατροφικές eπeμβάσeις μe πέντe eπαναλήψeις η κάθe μία. Οι πeιραματικές ομάδeς πeριeλάμβαναν την ομάδα του μάρτυρα στην οποία χορηγήθηκe ένα βασικό σιτηρέσιο eπαρκές σe σeλήνιο και βιταμίνη E (0,3 και 80 mg/kg αντίστοιχα), την ομάδα Se+ στην οποία χορηγήθηκe eπιπρόσθeτα 1 mg/kg σeληνίου, την ομάδα E + στην οποία χορηγήθηκe eπιπρόσθeτα 350 mg/kg βιταμίνη E και τέλος την ομάδα Se+E+ στην οποία χορηγήθηκe συνδυασμός σeληνίου και βιταμίνης E σe συγκeντρώσeις 1 και 350 mg/kg αντίστοιχα. Τα σιτηρέσια ήταν ισοαζωτούχα και ισοeνeργeιακά. Για την eπιπλέον προσθήκη σeληνίου χρησιμοποιήθηκe σύμπλοκο της L-σeληνομeθeιονίνης μe ψeυδάργυρο, eνώ για την προσθήκη βιταμίνης η DL-α-τοκοφeρόλη. Το πeίραμα διήρκeσe 42 ημέρeς. Η συγκέντρωση σeληνίου στο πλάσμα αυξήθηκe στις eπeμβάσeις μe σeλήνιο, eνώ η eνeργότητα της υπeροξeιδάσης της γλουταθeιόνης στο αίμα αυξήθηκe σe όλeς τις eπeμβάσeις σe σχέση μe τον μάρτυρα. Η αποϊωδιάση της ιωδιοθυρονίνης (τύπου Ι) στο ήπαρ και οι συγκeντρώσeις των θυρeοeιδικών ορμονών στο αίμα δeν eπηρeάστηκαν από οποιαδήποτe eπέμβαση. Συμπeρασματικά, η συμπλήρωση μe σeλήνιο ή βιταμίνη E μeμονωμένα ή σe συνδυασμό πέραν των αναγκών του ζώου δeν eπηρέασαν τα eπίπeδα των θυρeοeιδικών ορμονών, ούτe την eνeργότητα της ηπατικής αποϊωδιάσης υπό τις συνθήκeς που eξeτάστηκαν.

The role of thyroid hormones on the transition to anestrous has been well established in ewes, but their possible involvement in the induction of reproductive activity remains obscure. The aim of the present study was to investigate the role of thyroid hormones in the induction of the first ovulation in relation to "ram effect" in ewes. Fourty-four ewes of the Greek Zackel mountain type breed were used. The ewes were housed separately from the rams until day 0 (entrance of rams). Blood samples were collected weekly for 4 weeks until 11 weeks after the ram entrance for the determination of thyroxin and progesterone levels. Thirty-five out of 44 ewes (group A) had a silent heat, while the rest 9 ewes (group B) exhibited a delayed estrus. Thyroxin levels rose immediately after ram entrance in animals of group A, but in group Β the increase in thyroid hormone levels was evident only after the first week. The difference in T4 levels between week 0 and 1 for ewes of group A was significantly higher than that observed for animals of group Β (p<005). The pattern of progesterone release was similar between the two groups, but a two week delay in the increase of progesterone concentration was observed in animals of group Β compared to group A. It is concluded that thyroid hormones may act at the beginning of the breeding season to cause a modification in gonadotrophin secretion leading to early ovulation.

Ovarian and thyroid activity was studied in 10 ewes of Lacuane breed during one year. Ewes were maintained separately from rams and were fed. The aim of the study was to determine the duration of the anestrus period. Blood samples were collected weekly for the determination of progesterone levels. Thyroxine levels were also determined. Progesterone concentrations > 1 ng/ml were considered as indicative of ovulation, whereas levels between 0.5-0.9 ng/ml as indicative of follicle luteinizations or short lived corpus luteum. Two ewes showed persistent corpus luteum which regressed in deep anestrus period. The first ovulation occurred on 18th August ±10 days. The duration of the breeding season (the interval from the first to the last ovulation) was estimated to be 158 ± 8 days and the number of ovarian cycles during this period was 9.0 ± 0.6 per ewe. A significant correlation was observed between the time of the last ovulation and the duration of the breeding season, (Y=l4l.4+0.96X, r2 = 0.71, P<0.01). Serum thyroxine levels in every fifteen days samples fluctuate from 47 ± 4 during the first half of August to 82 ± 5 during the second half of December. Mean thyroxine levels during the time of increasing daylength (23rd December to 22nd June) were 71.2 ± 2 ng/ml and during that of decreasing daylength (23rd June to 22nd December) 59.4 ± 3 ng/ml, (p<0.001). In conclusion, this study showed that the ewes of the Lacaune breed exhibit a long anestrous period compared to the indigenous Greek breeds. Hormonal control of estrus is necessary for the out-of season lambing. Finally, thyroid function shows a significant seasonality, as has been demonstrated in all other breeds of sheep studied so far.

The aim of this study was to evaluate the effect of the non-selective phosphodiesterase inhibitor 3isobutyl-1-methyl-xanthine (IBMX) given concomitantly with eCG on reproductive performance of ewes.In trial 1, eighty ewes were allocated into 8 groups (AC, A1, A2, A3 and DC, D1, D2, D3).Oestruses were synchronized by progestagen sponges.At sponges removal all ewes of A groups received 400 IU of eCG.Concomitantly with eCG, ewes of groups A1, A2 or A3 received IMBX at the dose of 2.5, 5.0 or 25.0 mg, respectively.Ewes of D1, D2 or D3 groups received only IBMX at the same doses, respectively; in each case, ewes of AC or DC groups were controls (C).In trial 2, one hundred eighteen ewes were allocated into 4 groups (BC1, B1 and BC2, B2).Oestruses were synchronized by progestagen sponges.At sponges removal ewes of BC1 or B1 received 200 IU of eCG, while ewes of BC2 or B2 groups received 100 IU.At the same time only ewes of B1 or B2 groups received 2.5 mg IBMX.In both trials, 48 hours after hormonal treatment, ewes were mated.In trial 1, pregnancy or lambing rate did not differ among A or D groups (P > 0.05).Total lambs per ewe were significantly higher in A1 compared to AC, A2, A3 or D1 groups (P < 0.05), but did not differ among D groups (P > 0.05).In trial 2, pregnancy or lambing rate did not differ among B groups (P > 0.05).Total lambs per ewe were significantly higher (P < 0.05) in B1 and B2 compared to BC1 and BC2 groups, respectively.These results indicate that IBMX combined with eCG at the end of an oestrus synchronization treatment improves litter size probably by increasing ovulation rate in ewes.This latter effect seems to be mainly dependent on the amount of gonadotrophins used.

The aim of this study was to characterise the effects of maternal undernutrition during gestation on hepatic gluconeogenic enzyme gene expression and to determine whether such effects are mediated through epigenetic changes in the glucocorticoid receptor (GR). Pregnant ewes were fed a 50% nutrient-restricted diet from Day 0 to 30 (R1) or from Day 31 to 100 of gestation (R2) or a 100% diet throughout gestation (Control). After parturition lambs were fed to appetite. At 10 months of age offspring were euthanised and livers were removed. Maternal undernutrition did not affect offspring bodyweight at birth or at 10 months of age. However, liver weight of males of the R2 group was lower (P < 0.05) in relation to other groups. A significant (P < 0.05) hypomethylation of the hepatic GR promoter was revealed in males of the R2 group and a tendency towards the same in the R1 group, along with increased (P < 0.001) GR gene expression in both restricted groups. A significant increase (P < 0.05) in hepatic phosphoenolpyruvate carboxykinase (PEPCK) gene expression was found in male lambs of both undernourished groups, accompanied by increased (P < 0.01) protein levels, while no differences were detected for glucose-6-phosphatase (G6Pase) mRNA abundance and protein levels. In female lambs, no differences between groups were observed for any parameter studied. These data represent potential mechanisms by which insults in early life may lead to persistent physiological changes in the offspring.

Fish stress may result in inhibition of reproduction, development and growth. Thus, appropriate indices should be developed to accurately define the physiological plasticity of fish, in terms of coping with stress. Sea bream individuals were subjected to physical stress (fasting and confinement). DNA fragmentation of liver cells was assessed, in addition to gene expression of selected genes and plasma cortisol levels determination. Stress response was characterized with significant temporal alterations. Increased DNA fragmentation was observed as an aftereffect of physical stress and consequently gene expression of tp53 was stimulated. The expression pattern of glucocorticoid receptor (nr3c1) was directly correlated with plasma cortisol. Furthermore, glucokinase (gk) gene expression was considerably upregulated under acute stress, depicting putative energetic demands. Finally, igf1 downregulation during stress, reflects the suppression of the GH/IGF axis and the substantial stress effects on growth. To conclude, most of the indices described in the present study could be synergistically used, in order to robustly quantify physical stress in marine teleosts.

The emerging immune system is vulnerable to insult not only during fetal life, but also through colostrum transfer of maternal factors with immunomodulatory functions. The aim of the present study was to examine the effects of maternal undernutrition during late gestation and/or lactation on colostrum and milk synthesis, as well as on immunological parameters in offspring. Pregnant ewes were fed to 100% of nutrient requirements throughout pregnancy and lactation (Control) or to 50% during lactation (R1) or during the last 20 days of pregnancy and lactation (R2). Colostrum samples were collected 3 and 18h after parturition and thymus glands were obtained from 5-month-old offspring. Lamb birthweight did not differ between groups, whereas growth rate was significantly lower in males in the R1 group and in females in both undernourished groups. There was a significant reduction in lactose percentage in the 18-h colostrum of the R2 group. The IgG concentration, as a percentage of protein, was significantly increased in 3-h colostrum samples of the R2 group. Quantitative polymerase chain reaction analysis revealed a significant increase in the expression of Toll-like receptor (TLR) 2, TLR4 and TLR9 in the thymus gland of female lambs in both undernourished groups. In conclusion, early life nutritional imbalances may impact on immune system function in later life due to programming effects.

The objective of the present experiment was to investigate the implications of severe maternal undernutrition on the post-weaning behavior of rabbits. Thirty two does were randomly assigned to four groups: the control group (C) that was fed 100% of the recommended energy maintenance requirements throughout pregnancy and lactation and the U1, U2 and U3 groups that were fed 50% of the recommended energy maintenance requirements between the 6th and the 19th day of pregnancy, between the 20th and the 27th day of pregnancy and between the 3rd and the 10th day of lactation, respectively. At the age of 50 and 65 days, behavior of rabbits in cages was recorded and rabbits were further subjected to an open-field test; a paradigm used as an indicator of fear and emotional distress. Significant differences were found between the U2 and the other experimental groups for the duration of eating and drinking, and duration of locomotory and investigatory behaviors (P<0.05). At the age of 65 days, duration of comfort behaviors was also lower in the U2 compared to the other groups (P<0.05). On the other hand, duration of resting appeared to be the highest in the group of rabbits born from undernourished does between the 20th and the 27th day of pregnancy (P<0.05). Duration of resting was significantly increased, although frequency and duration of eating and drinking were significantly decreased at the age of 65 days (P<0.05). Male rabbits had greater values for locomotory and investigatory behaviors, and duration of eating and drinking compared to the females (P<0.01). A decreased activity of rabbits during the light period was observed (as expected), whereas an increase in duration of locomotory and investigatory behaviors was observed during the first four and the last 4h of the light and dark periods, respectively (P<0.05). Rabbits born from the U1 and U2 group of does displayed increased rates of latency to leave the start position compared to the other groups during the implementation of the open-field test (P<0.05). No other significant differences in the exhibition of the examined behaviors were found between the treatment groups, with the exception of 'moving forelegs' activity that had the lowest value in the U3 group of rabbits. It is concluded that severe maternal undernutrition (50% of the recommended maintenance requirements) especially between the 20th and the 27th day of pregnancy has significant effects on the exhibition of rabbits' post-weaning behavior, since the offspring from the U2 undernourished does were significantly less active compared to the other experimental groups.

An experiment was conducted in order to evaluate the effects of gestational undernutrition of rabbit does on growth, carcass composition and meat quality of the offsprings. Thirty primiparous non lactating rabbit does were artificially inseminated and randomly divided in three treatment groups: Control (C; fed to 100% of maintenance requirements throughout gestation, n = 10), early undernourished (EU; fed to 50% of maintenance requirements during days 7-19 of gestation, n = 10) and late undernourished (LU; fed to 50% of maintenance requirements during days 20-27 of gestation, n = 10). During the 4th week of the gestation period, LU does significantly lost weight compared to C and EU groups (P<0.05). At kindling, C does produced litters with higher proportions of stillborn kits (P<0.05) while the total litter size (alive and stillborn kits) was not different among groups (10.7, 12.8 and 12.7 kits in C, EU and LU groups, respectively). Kit birth weight tended to be lower in the LU group. During fattening, body weight and feed intake were not different among offsprings of the three experimental groups. Moreover, the maternal undernutrition did not have any impact on carcass composition of the offsprings in terms of carcass parts and internal organs weights as well as meat quality of L. lumborum muscle (pH24, colour, water holding capacity and shear values) at slaughter (70 days of age). Therefore, it can be concluded that the gestational undernutrition of the mother does not have detrimental effects on the productive and quality traits of the offsprings.