Effects of guanidino acetic acid and betaine supplementation on growth, dietary nutrient digestion and intestinal creatine metabolism in sheep.

BACKGROUND: The intestine of young ruminants is in the developmental stage and has weaker resistance to the changes of external environment. Improving intestinal health is vital to promoting growth of young ruminants. This study investigated effects of guanidino acetic acid (GAA) and rumen-protected betaine (RPB) supplementation on growth, dietary nutrient digestion and GAA metabolism in the small intestine of sheep. METHODS: Eighteen healthy Kazakh rams (27.46 ± 0.10 kg of body weight and 3-month old) were categorized into control, test group I and test group II, which were fed a basal diet, 1500 mg/kg GAA and 1500 mg/kg GAA + 600 mg/kg RPB, respectively. RESULTS: Compared with control group, test group II had increased (p < 0.05) average daily gain, plasma creatine level, ether extract (EE) and phosphorus digestibility on day 30. On day 60, the EE apparent digestibility, jugular venous plasma GAA, GAA content in the duodenal mucosa and GAA content in the jejunal and ileal mucosa of test group II were higher (p < 0.05) than other groups. Transcriptome analysis revealed that the differentially expressed genes (DEGs) involved in the duodenal pathways of oxidative phosphorylation and non-alcoholic fatty liver disease were significantly altered in test group II versus test group I (p < 0.05). Moreover, in the jejunum, the MAPK signalling pathway, complement and coagulation cascade and B-cell receptor signalling pathway were significantly enriched, with ATPase, solute carrier transporter protein, DHFR, SI, GCK, ACACA and FASN being the significantly DEGs (p < 0.05). CONCLUSION: Dietary supplementation of RPB on top of GAA in sheep diets may promote sheep growth and development by improving the body's energy, amino acid, glucose and lipid metabolism capacity.

Genistein effect in cultured ovine ovarian granulosa cells.

Genistein, an isoflavone has the potential to mimic, augment, or dysregulate the steroid hormone production pathways. We hypothesized that genistein affects the granulosa cell (GCs) functions through a series of biochemical, molecular, and genomic cascades. The present study was conducted to evaluate the impact of genistein exposure on GCs viability, apoptosis, and steroidogenesis. The present study involved 3/5 days of exposure to genistein on GCs collected from abattoir-derived ovine ovaries at doses of 0, 1, 10, 25, 50, and 100 µM. The harvested GCs were used for growth, cytotoxicity, and gene expression studies related to apoptosis, growth, and steroidogenesis. We observed that genistein had both stimulatory at 10 and 25 µM levels as well as inhibitory effects at 50 and 100 µM levels on the growth and proliferation of GCs. Genistein significantly decreased the levels of 17ß-estradiol at higher exposure (50 and 100 µM), whereas the progesterone level increased significantly as the genistein exposure increased. Additionally, genistein could also alter the mRNA expression of the steroidogenic receptor, enzymes, proteins, and growth-related genes suggesting that genistein could potentially alter the steroidogenic pathways. We conclude that genistein can interfere with cell survival and steroidogenesis by exhibiting a dose-dependent biphasic response on the viability, growth-related parameters, and the synthesis of 17ß-estradiol in the cultured GCs.

Characterization of TNSALP expression, localization, and activity in ovine utero-placental tissues†.

Tissue-nonspecific alkaline phosphatase (TNSALP; encoded by ALPL gene) has a critical role in the regulation of phosphate homeostasis postnatally. However, the utero-placental expression of TNSALP and the role in phosphate transport in pregnancy is poorly understood. Estrous cycles of ewes were synchronized, and ewes were euthanized and hysterectomized on Days 1, 9, or 14 of the estrous cycle or bred to fertile rams and euthanized and hysterectomized on Days 9, 12, 17, 30, 50, 70, 90, 110, or 125 of pregnancy. The expression of ALPL mRNA, immunolocalization of TNSALP protein, and quantification and localization of TNSALP enzymatic activity was performed on ovine endometria and placentomes. Day of the estrous cycle did not alter ALPL mRNA expression or enzymatic activity of TNSALP. TNSALP protein localized to uterine epithelial and stromal cells, blood vessels, myometrium, caruncular, and cotyledonary stroma. TNSALP activity was localized to uterine epithelia, blood vessels, caruncular stroma (from Day 70 of gestation), and the apical surface of chorionic epithelia (from Day 50 of gestation). TNSALP protein and activity localized to the apical surface of uterine epithelia during the estrous cycle and in early pregnancy. Endometrial TNSALP enzymatic activity was downregulated on Days 17 and 30 of gestation (P < 0.05). Expression of ALPL mRNA decreased in late gestation in endometria and placentomes (P < 0.05). TNSALP activity peaked in placentomes on Days 70 and 90 of gestation. Collectively, these results suggest a potential role of TNSALP in the regulation of phosphate transport and homeostasis at the maternal-conceptus interface in ruminants.

In vitro interaction of the pesticides flupyradifurone, bupirimate and its metabolite ethirimol with the ATP-binding cassette transporter G2 (ABCG2).

ABCG2 is an ATP-binding cassette efflux transporter that is expressed in absorptive and excretory organs such as liver, intestine, kidney, brain and testis where it plays a crucial physiological and toxicological role in protecting cells against xenobiotics, affecting pharmacokinetics of its substrates. In addition, the induction of ABCG2 expression in mammary gland during lactation is related to active secretion of many toxicants into milk. In this study, the in vitro interactions between ABCG2 and three pesticides flupyradifurone, bupirimate and its metabolite ethirimol were investigated to check whether these compounds are substrates and/or inhibitors of this transporter. Using in vitro transepithelial assays with cells transduced with murine, ovine and human ABCG2, we showed that ethirimol and flupyradifurone were transported efficiently by murine Abcg2 and ovine ABCG2 but not by human ABCG2. Bupirimate was not found to be an in vitro substrate of ABCG2 transporter. Accumulation assays using mitoxantrone in transduced MDCK-II cells suggest that none of the tested pesticides were efficient ABCG2 inhibitors, at least in our experimental conditions. Our studies disclose that ethirimol and flupyradifurone are in vitro substrates of murine and ovine ABCG2, opening the possibility of a potential relevance of ABCG2 in the toxicokinetics of these pesticides.

Fatty acid and oxidative shelf-life profiles of meat from lambs fed finisher diets containing Acacia mearnsii leaf-meal.

Five diets containing Acacia mearnsii leaf-meal (AMLM; 0, 50, 100, 150 and 200 g/kg DM) substituted for Triticum aestivum bran were fed to lambs for 42 days. The effect of diet and retail display period on meat fatty acid (FA) composition (day 1); colour, antioxidant activity, myoglobin and lipid oxidation (day 1, 3, 5, 7 and 9); protein oxidation (1, 3 and 7 d) and instrumental tenderness (day 1, 5 and 10) were evaluated. Dietary AMLM linearly decreased (P ≤ 0.05) individual (14:0, 16:0, 18:0) and total saturated FA and increased (P ≤ 0.05) trans(t)-monounsaturated FA (MUFA) mainly t10/t11-18:1, individual and total conjugated linoleic acids, n-3 and n-6 polyunsaturated FA (PUFA) contents. The contents of cis(c)-MUFA, mainly c9-18:1, exhibited a quadratic response reaching a minimum at 50 g/kg AMLM (P ≤ 0.05). Meat antioxidant on day 9 was higher (P ≤ 0.05) for diets containing ≥100 g/kg DM AMLM compared to the other diet × retail display period interactions. Relative to the other interactions, meat redness values were lowest on day 7 and 9 for AMLM diets containing ≥150 g/kg DM (P ≤ 0.05). Dietary addition of AMLM increased (P ≤ 0.05) meat lightness and oxymyoglobin, and reduced (P ≤ 0.05) TBARS and instrumental tenderness values. However, oxymyoglobin values declined (P ≤ 0.05) over the retail display period, while lightness, metmyoglobin, TBARS and carbonyls increased (P ≤ 0.05). Results indicate that AMLM up to 200 g/kg DM in lamb finisher diets, improves meat fatty acid composition, tenderness, and lipid shelf-life.

Antioxidant action of yerba mate on carcass and meat characteristics and fatty acid profile in meat and fat of lambs finished in tropical pastures.

The objective was to evaluate the effect of the supplementation with natural antioxidants from Yerba mate (Ilex paraguariensis St. Hil.) on the performance, carcass and meat characteristics, and fatty acid profile in meat and fat of Texel × Ile de France lambs kept in Brachiaria-grass pasture. Twenty lambs with a mean age of 90 days and 26.3 kg of BW were distributed in a completely randomized design in two treatments with 10 replicates/treatment: Control-protein-energy supplement based on corn and soybean meal (150 g/kg DM of crude protein) without the addition of natural antioxidant yerba mate and Yerba Mate - energy protein supplement with the addition of yerba mate (110 g/kg DM). There was no treatment effect on animal performance and carcass characteristics. The subcutaneous fat thickness was significantly higher for lambs treated without yerba mate. There was no effect of nutritional treatments on the oxidative markers of lamb meat. The muscle of the animals treated with yerba mate showed a higher concentration of unsaturated and polyunsaturated fatty acids elaidic, linolenic, thymnodonic, docosadienoic, and ceorvonic. The fat of the animals treated with yerba mate showed a higher concentration of palmitoleic acid, linoelaidic acid, heneicosanoic acid, dihomo-γ-linolenic acid, and arachidonic acid. The concentration of polyunsaturated fatty acids was significantly higher in meat and fat of lambs treated with yerba mate. Including yerba mate in the diet of lambs kept on Brachiaria pastures improves the lipid profile of polyunsaturated fatty acids in meat and fat, without altering the performance of the animals.

Ovine endometrial estrogen receptor expression is altered following PG-600 administration.

BACKGROUND: Dysregulation of the estrogen receptor 1 (ESR1) expression during the establishment of pregnancy could contribute to reduce fertility reported in ewes treated with PG-600. OBJECTIVES: The objective of this study was to evaluate the effect of treatment with PG-600 on ESR1 expression in the ovine endometrium during early diestrus. METHODS: Polypay ewes (n = 24) that had exhibited an oestrous cycle of normal duration (16-18 days) were treated with intravaginal progesterone-releasing device (CIDR) for 9 days. Cloprostenol was administrated two days before CIDR withdrawal. On the day of CIDR withdrawal (day 0), ewes received a 5 mL intramuscular injection of PG-600 (400 IU equine chorionic gonadotropin and 200 IU human chorionic gonadotropin) or saline. Blood samples were collected before treatment and on the day of tissue collection to determine serum estradiol-17ß and progesterone concentrations using radioimmunoassay. On days 4 and 7, six ewes from each treatment group were anaesthetised and a laparotomy was performed to obtain intercaruncular endometrial samples. Endometrial samples were collected ipsilateral to the ovary bearing the highest number of corpora lutea. An estradiol exchange assay was used to determine ESR1 concentration. RESULTS: Estradiol concentrations did not differ by time or treatment, but progesterone concentrations were significantly higher in the PG-600-treated group on day 7 despite a similar number of corpora lutea. Endometrial ESR1 concentration was significantly reduced on day 7 in the PG-600 group. CONCLUSIONS: In conclusion, although progesterone was higher than controls on day 7, ESR1 did not differ from controls suggesting that treatment with PG600 is unlikely to impair reproductive potential.

Expression pattern and cellular localization of two critical non-nuclear progesterone receptors in the ovine corpus luteum during the estrous cycle and early pregnancy.

The study aimed to investigate the expression and cellular localization of two critical non-nuclear progesterone receptors, including membrane-associated-progesterone-receptor-component-1 (PGRMC1) and progestin and adipoQ receptor family member 7 (PAQR7) throughout the estrous cycle and early pregnancy in ovine corpus luteum (CL). Ewes were randomly grouped into cyclic (C, n = 4 per group) or pregnant (P, n = 4 per group) groups. Following slaughtering, the CL was obtained from both cyclic and pregnant ewes on days 12 (C12 and P12), 16 (C16 and P16), and 22 (C22 and P22). Western blotting and RT-qPCR were utilized to assess the expression levels of PGRMC1 and PAQR7, whereas immunohistochemistry was performed to determine the localization of PGRMC1 and PAQR7 in CL. Data were evaluated by one-way ANOVA, and the P < 0.05 was considered a significant difference. PGRMC1 was shown to be expressed in both small and large luteal cells and endothelial cells in CL, while PAQR7 expression was only found in small and large luteal cells. Compared to cycle days, pregnancy increased the expression of PGRMC1. PAQR7 did not differ during early pregnancy but reduced during the functional luteolysis stage (C16). mRNA and protein expression patterns for PGRMC1 and PAQR7 were similar on the studied days. This is the first study that demonstrates the expression and cellular localization of PGRMC1 and PAQR7 in ovine CL. We suggest that these receptors could execute a significant role in the ovine CL life span in both cyclic changes and the establishment of pregnancy.

Expression patterns of genes in steroidogenic, cholesterol uptake, and liver x receptor-mediated cholesterol efflux pathway regulating cholesterol homeostasis in natural and PGF2α induced luteolysis as well as early pregnancy in ovine corpus luteum.

The aim was to evaluate the expression of genes of steroidogenic, cholesterol uptake, and liver X receptor (LXR) mediated cholesterol efflux pathway in ovine corpus luteum (CL) during natural and prostaglandin F2α (PGF2α) induced luteolysis and early pregnancy. For this study, two experiments were carried out 1); ewes were grouped into two sub-groups as cyclic 12 (C12, n = 4) and 16 (C16, n = 4) and pregnant 12 (P12, n = 4), 16 (P16, n = 4), and 22 (P22, n = 4). Additionally, 2) ewes were grouped into four groups following treatment of PGF2α, the duration of PGF2α challenge at 1 (PG1, n = 4), 4 (PG4, n = 4), and 16 (PG16, n = 4) hours on day 12 of the cycle was compared with 0 h. The corpus luteum tissue samples were collected on the corresponding estrus cycle and pregnancy days, and RNA was extracted using Trizol. mRNA expression levels of the steroidogenic (StAR, CYP11A1, and HSD3B1) and cholesterol uptake receptors (SCARB1 and LDLR) and LXR pathway (NR1H3, NR1H2, ABCA1, and ABCG1) were assessed using quantitative PCR (qPCR), and protein of LXR pathway was investigated using western blot. In-situ hybridization was used to detect mRNA localization. Steroidogenic and cholesterol uptake mRNAs were decreased in C16, while NR1H2 and ABCG1 were increased in C16, compared to C12. Steroidogenic and cholesterol uptake mRNA was greater in P16 than in C16. NR1H2 and ABCA1 protein expression were higher in P16 than in C16. LDLR mRNA was higher in P22 than in P12, while SCARB1 was higher in P16 than in P12. NR1H2 mRNA was greater in P22 than in P12. Steroidogenic and cholesterol uptake mRNA were decreased in PGF2α-induced luteolysis groups against C12. ABCG1 mRNA was higher in PG16 than in PG4 and PG1. The reduction of lipoprotein receptors rather than LXR-mediated reverse transport may contribute to the decline in progesterone (P4) in natural and functional luteolysis.

Effect of L-citrulline supplementation on sperm characteristics and hormonal and antioxidant levels in blood and seminal plasma of rams.

With the aim of providing a theoretical basis for the application of L-citrulline (L-Cit) in animal husbandry, the effects of L-Cit on reproductive hormone levels, antioxidant capacity and semen quality of rams were studied by feeding them varying doses of L-Cit. A total of 32 rams were randomly divided into four groups with eight rams each. After all rams were trained to donate sperm normally, the control group was fed a basic diet, whereas the experimental groups I, II and III were provided with feed supplemented with 4, 8 and 12 g/d of L-Cit respectively. The experiment was conducted for 70 days, during which blood samples were collected from the jugular vein on days 0, 15, 30, 45 and 60, and semen samples were collected on days 0, 20, 40 and 60. In the same group, 100 µl of semen was used to test for quality, The rest of the semen sample and blood samples were centrifuged at 600 g for 15 min, and the supernatant and serum, respectively, were used to determine the levels reproductive hormones and antioxidant indices. Ram semen samples were also collected on day 70 and used to study sperm plasma membrane, substitution and mitochondrial membrane potential. Compared with the control group, the groups receiving L-Cit showed an increase in sperm concentration and number of linear motile sperm (p < .01); a decrease in the number of dead sperm (p < .01); an increase in sperm viability, particularly in groups II and III (p < .01); and an increase in sperm mitochondrial membrane potential (p < .01). Moreover, groups I, II and III showed significantly higher levels of serum gonadotropin-releasing hormone (GnRH), glutathione peroxidase (GSH-Px) and nitric oxide (NO) (p < .01). Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels increased in groups I (p < .05), II (p < .05) and III (p < .01), whereas testosterone (T), catalase (CAT) and superoxide dismutase (SOD) levels increased in groups I and II (p < .01). Serum total antioxidant capacity (T-A) increased (p < .05), whereas both hydroxyl radical (·OH) and peroxy radical ( O 2 · - ) levels decreased (p < .01). Compared with the control, all groups had significantly higher SOD and GSH-Px in their seminal plasma (p < .01), and groups I, II (p < .05 for both) and III (p < .01) had higher levels of GnRH and FSH. LH, CAT and NO levels increased in group I (p < .05), II and III (p < .01 for both); malondialdehyde levels decreased in groups I, II (p < .05 for both) and group III (p < .01); and O 2 · - levels decreased in groups I, II and III (p < .01). Under our experimental conditions, GnRH, FSH, LH, T, CAT, SOD, T-A, GSH-PX and NO levels in the serum and seminal plasma of rams receiving L-Cit increased, whereas Oestradiol (E2 ), O 2 · - and ·OH levels in the seminal plasma decreased; this improved the semen quality of rams supplemented with L-Cit. Moreover, supplementation with 12 g/d gave the best results.

Effects of Foliar Application of Nano-molybdenum Fertilizer on Copper Metabolism of Grazing Chinese Merino Sheep (Junken Type) on Natural Grasslands Under Copper and Cadmium Stress.

In recent decades, the groundwater contaminated by mineral development and metal smelting has seriously polluted natural grasslands, resulting in heavy metal residues in soils and forages exceeding the standard, especially copper (Cu) and cadmium (Cd). After animals intake contaminated forages, heavy metals may accumulate in animal tissues and threaten human health through the food chain. Previous studies found that molybdenum (Mo) fertilizer from ammonium molybdate or potassium molybdate could alleviate the decrease of antioxidant capacity caused by heavy metal poisoning, but the application of nano-Mo fertilizer in sheep is still lacking. To investigate the effects of nano-Mo fertilizer on Cu metabolism of grazing Chinese Merino sheep (Junken Type) on natural pastures under Cu and Cd stress, fertilizing experiment was carried out in the Bayanbulak Grassland in the northwest of Xinjiang Uygur Autonomous Region, China. A total of 24 hm2 fenced grassland contaminated by heavy metals was randomly divided into four groups (3 replications/group and 2 hm2/replication). The experimental groups were applied 0 g Mo, 100 g Mo, 200 g Mo, and 300 g Mo per hectare for the control group, group I, group II, and group III, respectively, through foliar spraying fertilization. A total of 72 Chinese Merino sheep (1 year old, 43.8 ± 2.3 kg) grazing on polluted natural grasslands, with 18 sheep per group, were randomly assigned to the experimental pastures for 30 days. The results showed that the Mo content in soil in group II and group III nwas higher than that in the control group (P < 0.05); the Cd content in soil in group II and group III was lower than that in the control group (P < 0.05), and the Cu content in soil in fertilized pastures was lower than that in the control group (P < 0.05). The Mo content in herbage in fertilized pastures was higher than that in the control group (P < 0.05), and the content of Cu in herbage in fertilized pastures was lower than that in the control group (P < 0.05). The contents of iron (Fe) and Mo in blood and liver of grazing animals from fertilized pastures were higher than that in the control group (P < 0.05). The Cd content in blood of grazing animals in group II and group III was lower than that in the control group (P < 0.05). The Cu content in blood and liver of grazing animals in fertilized pastures was lower than that in the control group (P < 0.05). The content of selenium (Se) in blood of grazing animals in group II and group III was higher than that in the control group (P < 0.05). The levels of blood including hemoglobin (Hb), erythrocyte count (RBC), and packed cell volume (PCV) in group II and group III were higher than that in the control group (P < 0.05). The white blood cell (RBC) count in group II and group III was lower than that in the control group (P < 0.05). The activities of serum superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT), and ceruloplasmin (Cp) in group II and group III were higher than that in the control group (P < 0.05). The content of malondialdehyde (MDA) in group II and group III was lower than that in the control group (P < 0.05). In conclusion, the application of nano-Mo fertilizer on Cu- and Cd-contaminated grasslands changed the contents of mineral elements in soil, forage, and blood of grazing sheep, improved the antioxidant capacity, affected the Cu metabolism of grazing Chinese Merino sheep caused by Cu and Cd pollutions, and alleviated the toxic damage of heavy metal pollutions.

Folic acid supplementation during pregnancy modulates hepatic methyl metabolism and genes expression profile of neonatal lambs of different litter sizes.

Maternal folic acid (FA) plays an important role in the fetus development, but it is unknown the response of hepatic metabolism in the offspring from different litter sizes to maternal FA supplementation. In the present study, this was done by feeding the ewes with 0, 16 and 32 mg/(kg·DM) FA supplemented diet during pregnancy and analysing the hepatic one-carbon metabolism-related indices and gene expression in the neonatal lambs of different litter sizes (twins, TW; triplets, TR). Regardless of litter sizes, the concentrations of folate, methionine, S-adenosylmethionine and DNA methyltransferase increased significantly, but homocysteine and S-adenosylhomocysteine decreased in the liver of newborn lambs from ewes whose diet was supplemented with FA. In TW, maternal FA status has little effect on hepatic genes expression profile of newborn lambs, and no significant enriched pathway was found. However, DEG involved in cell proliferation such as CCNA2, CCNB2, CCNE2, CDK1 and BUB1 were significantly enriched when the ewes were supplemented with FA in TR groups. In addition, nucleotide synthesis-related genes such as POLD1, POLD2, MCM4 and MCM5 were enriched markedly in DNA replication and pyrimidine metabolism pathways in triplets when a higher FA ingestion [32 mg/(kg·DM)] was implemented in ewes. This finding demonstrated that the hepatic methyl metabolism in TW and TR newborn lambs was regulated by maternal FA status. The hepatic cell proliferation and nucleotide metabolism related genes in TR were more susceptible to maternal dietary FA supplementation during pregnancy.

Effect of magnesium ammonium phosphate on the expression of adhesion molecules in sheep renal tubular epithelial cells.

Adhesion molecules play an important role in urinary calculus formation. The expressions of adhesion molecules in renal tubular has been reported in some animals. However, the role of adhesion molecules in the process of sheep urinary calculus formation is still unclear. The magnesium ammonium phosphate (MAP) is the main component of sheep urinary calculus. In this paper, the sheep renal tubular epithelial cells (RTECs) were isolated and treated with MAP, the expressions of osteopontin (OPN), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and apoptosis-related indicators caspase-3, Bcl-2 and Bax in RTECs were observed, the viability of RTECs was detected by Cell Counting Kit-8 (CCK-8). The levels of superoxide dismutase (SOD) and malondialdehyde (MDA), and the expressions of inflammatory factors Interleukin-6 (IL-6), Interleukin-1 (IL-1), Interleukin-17 (IL-17) and tumor necrosis factor-α (TNF-α) were measured by enzyme-linked immunosorbent (ELISA). The histopathological observation of kidney in urolithiasis sheep was made. The results showed that MAP could reduce the viability and SOD activity, enhance the activity of MDA significantly and promote the expressions of IL-1, IL-6, IL-17 and TNF-α of RTECs. By western blot and qPCR methods, the expressions of ICAM-1, VCAM-1 and OPN increased in 48 h. In addition, the expression of caspase-3 increased significantly and the ratio of Bcl-2/Bax reduced with exposure to MAP. The renal tissue structure was seriously damaged, the RTECs in urolithiasis sheep were degenerative and necrotic.

Insights into the lipidome and primary metabolome of the uterus from day 14 cyclic and pregnant sheep†.

In ruminants, conceptus elongation requires the endometrium and its secretions. The amino acid, carbohydrate, and protein composition of the uterine lumen during early pregnancy has been defined in sheep; however, a comprehensive understanding of metabolomic changes in the uterine lumen is lacking, particularly with respect to lipids. Here, the lipidome and primary metabolome of the uterine lumen, endometrium, and/or conceptus was determined on day 14 of the estrous cycle and pregnancy. Lipid droplets and select triglycerides were depleted in the endometrium of pregnant ewes. In contrast, select ceramides, diglycerides, and non-esterified fatty acids as well as several phospholipid classes (phosphatidylcholine, phosphatidylinositol, phosphatidylglycerols, and diacylglycerols) were elevated in the uterine lumen of pregnant ewes. Lipidomic analysis of the conceptus revealed that triglycerides are particularly abundant within the conceptus. Primary metabolite analyses found elevated amino acids, carbohydrates, and energy substrates, among others, in the uterine lumen of pregnant ewes. Collectively, this study supports the hypothesis that lipids are important components of the uterine lumen that govern conceptus elongation and growth during early pregnancy.

Integrated lipidomics and targeted metabolomics analyses reveal changes in flavor precursors in psoas major muscle of castrated lambs.

Castration may decrease off-odors and improve meat flavor. Meat flavor is generated through complex chemical reactions that involve hydrophilic and hydrophobic flavor precursors. In this study, we investigated the flavor precursors in psoas major muscles of castrated and intact sheep using lipidomics and targeted metabolomics. Castration decreased testosterone levels and increased intramuscular fat content. Six hundred fourteen lipid molecules confirmed showed a separation between castrated and intact sheep based on principal component analysis. Fourteen lipid species and 224 lipid molecules increased in castrated sheep. Targeted metabolomics analysis showed that 18 hydrophilic metabolites were affected by castration; however, only hypoxanthine significantly increased in the castration group. Among 45 volatiles identified, 1-octen-3-ol and hexanal were significantly higher in castrated sheep. These results revealed that lipids, hydrophilic metabolites, and volatile compounds in lamb were affected by castration, which might be beneficial in lamb quality.

Evolutionary-driven C-MYC gene expression in mammalian fibroblasts.

The extent to which mammalian cells share similar transcriptomes remains unclear. Notwithstanding, such cross-species gene expression inquiries have been scarce for defined cell types and most lack the dissection of gene regulatory landscapes. Therefore, the work was aimed to determine C-MYC relative expression across mammalian fibroblasts (Ovis aries and Bos taurus) via cross-species RT-qPCR and comprehensively explore its regulatory landscape by in silico tools. The prediction of transcription factor binding sites in C-MYC and its 2.5 kb upstream sequence revealed substantial variation, thus indicating evolutionary-driven re-wiring of cis-regulatory elements. C-MYC and its downstream target TBX3 were up-regulated in Bos taurus fibroblasts. The relative expression of C-MYC regulators [RONIN (also known as THAP11), RXRß, and TCF3] and the C-MYC-associated transcript elongation factor CDK9 did not differ between species. Additional in silico analyses suggested Bos taurus-specific C-MYC exonization, alternative splicing, and binding sites for non-coding RNAs. C-MYC protein orthologs were highly conserved, while variation was in the transactivation domain and the leucine zipper motif. Altogether, mammalian fibroblasts display evolutionary-driven C-MYC relative expression that should be instructive for understanding cellular physiology, cellular reprogramming, and C-MYC-related diseases.

Proteomic and metabolomic profiling reveals the involvement of apoptosis in meat quality characteristics of ovine M. longissimus from different callipyge genotypes.

Proteome and metabolome changes in muscles from callipyge mutation (+/C) and non-callipyge phenotype (+/+, C/+, and C/C) lambs were profiled to provide insight into the biochemical changes affecting meat quality attributes. M. longissimus thoracis from lambs with all four possible callipyge genotype (n = 4, C/+, C/C, +/C, and +/+) were collected after 3d aging and analyzed using mass-spectrometry based platforms. Among identified proteomes, cytochrome c (pro-apoptotic protein) was detected with significantly lower abundances in +/C. Anti-apoptotic HSP70, BAG3, and PARK7 were over-abundant in +/C, which could result in delayed apoptosis and possibly attributed to tougher meat in callipyge lambs. Eight glycolysis enzymes were overabundant in +/C lambs, whereas 3 enzymes involved in TCA cycle were overabundant in non-callipyge ones (C/C and/or C/+). Twenty-five metabolites were affected by genotypes (P < .05), including metabolic co-factors, polyphenols, and AA/short peptides. Our omics results provided insightful information for revealing the differences in biochemical attributes caused by callipyge mutation.

Effects of spirulina supplementation on lipid metabolism disorder, oxidative stress caused by high-energy dietary in Hu sheep.

The aim of this study was to investigate the effect of spirulina supplementation in a high-energy (HE) diet on lipid metabolism, oxidative status and immunity in Hu lambs. The lambs were assigned to two groups receiving either a standard diet (ST) or a HE diet. Each group was divided into three subgroups: no spirulina supplementation (control), 1% spirulina supplementation, or 3% spirulina supplementation. The body fat, serum cholesterol, triacylglycerol and oxidative stress increased in lambs fed the HE diet. However, 3% spirulina supplementation in the HE diet reduced above parameters and enhanced antioxidant capacity, including increased SOD activity and T-AOC content in serum and Longissimus thoracis et lumborum (LTL). Additionally, lambs receiving 3% spirulina supplementation showed an improvement in immunity-related parameters, including increased IgG concentration in serum and red and white blood cell counts. In conclusion, 3% spirulina supplementation in HE diet ameliorated lipid metabolic disorder and oxidative stress caused by a HE diet.

Pregnancy-induced changes in the transcript levels of prolactin receptor and its suppressor in the ovine hypothalamus and adenohypophysis.

The aim of this study was to analyse changes in the abundance of prolactin (PRL) receptor (PRLR) and suppressor of cytokine signalling-3 (SOCS-3) mRNA in the ventro-/dorsomedial nucleus (VMH/DMH) and arcuate nucleus (ARC) of the hypothalamus as well as in the median eminence (ME) and adenohypophysis (AP) in sheep at 30, 60, 90 and 120 d of pregnancy compared to non-pregnant animals. In the VMH/DMH, PRLR transcripts were detected only in non-pregnant ewes. In the ARC, the abundances of PRLR mRNA were higher in pregnant sheep on days 30 (p < .01), 90 (p < .01) and 120 (p < .05) than in non-pregnant sheep. In contrast, the expression of PRLR mRNA in the ME was lower (p < .01) in pregnant ewes at days 30 and 60 than in non-pregnant ewes and was undetectable at later stages of gestation. In all studied stages of pregnancy except day 60, the abundance of PRLR mRNA was higher (p < .01) in the ARC than in the AP, while in non-pregnant sheep, there were no differences (p ≥ .05) in the transcript levels between these two tissues. In non-pregnant ewes, the abundance of SOCS-3 mRNA in the AP was lower than that in any other studied tissue (p < .05-p < .01). In conclusion, the observed changes in PRLR and SOCS-3 mRNA abundance in the hypothalamus and AP during pregnancy may be important components of the mechanisms regulating the action of PRL in energy homeostasis and neuroendocrine interactions within the hypothalamic-pituitary axis.

Feeding lambs with silage mixtures of grass, sainfoin and red clover improves meat oxidative stability under high oxidative challenge.

This study investigated the oxidative stability of meat from lambs fed silages in which timothy grass was totally or partially replaced by sainfoin and/or red clover. Five groups of 8 lambs were fed the following silages: timothy grass (T), mixture (50:50) of timothy with either sainfoin (T-SF) or red clover (T-RC), mixture of timothy, sainfoin and red clover (50:25:25; T-SF-RC), or mixture (50:50) of sainfoin and red clover (SF-RC). Feeding the silages containing red clover (T-RC, T-SF-RC and SF-RC) decreased the deposition of vitamin E in muscle relative to the highly unsaturated fatty acids (P < .001), did not affect the oxidative stability of fresh meat, but reduced oxidative deterioration in cooked meat and in meat homogenates incubated with pro-oxidant catalysts (P < .001). The results of this study demonstrated that feeding lambs with silages containing sainfoin and red clover improve the oxidative stability of meat subjected to strong pro-oxidant conditions and suggest that these effects should be further clarified.