Effect of monosodium glutamate supplementation in diet on fatty acid profiles, genes expression related to lipid metabolism and egg yolk cholesterol in late phase of production in laying hens.

In an experiment with four treatments and five replicates, the effects of adding monosodium glutamate (MSG) to the diet in late phase of egg production was studied on performance, and lipid metabolism in laying hens. Dietary treatments included the control basal diet without MSG and the other treatments adding 0.4%, 0.8% and 1.2% MSG in the control diet respectively. The effect of supplementation of MSG on egg weight, egg production, feed conversion ratio and egg mass was insignificant (p < 0.05). Adding MSG to the diet significantly increased feed intake and blood polyunsaturated fatty acids concentration (p < 0.05). Intake of 0.8% and 1.2% MSG in the diet up regulated the mRNA expression of acetyl-coenzyme A carboxylase, fatty acid synthase and lipoprotein lipase in the abdominal and liver tissues in comparison to the control group. Blood very low-density lipoprotein-cholesterol, triglycerides and cholesterol concentration were increased in treatment fed with a diet containing 0.8% MSG compared to the control group (p < 0.05). The effect of MSG on total egg yolk cholesterol concentration was not significant. In conclusion, the results of the present experiment indicated that adding MSG increased feed intake and blood polyunsaturated fatty acid concentration.

Melatonin as a Smart Protector of Pregnancy in Dairy Cows.

The experimental objective was to examine the role of melatonin and its pathways in the maintenance of pregnancy in lactating dairy cows. Blood samples were collected at days 0, 16 and 32 after timed AI from cows (n = 200) in order to consider plasma melatonin concentrations and to conduct AOPP (advanced oxidation products of proteins) and TBARS (thiobarbituric acid reactive substances) tests. Luminal endometrial cells were collected at day 16 using a Cytobrush in all cows to determine mRNA expressions of melatonin receptor 1 (MT1), mouse double minute 2 (MDM2), MDM2 binding protein (MTBP), BCL2-associated X, apoptosis Regulator (BAX), p53 upregulated modulator of apoptosis (PUMA, gene symbol BBC3), mucin 1 (MUC1) and leukemia inhibitory factor (LIF). Plasma concentrations of melatonin were significantly greater in pregnant cows diagnosed pregnant at day 16 who sustained pregnancy to day 32 compared to nonpregnant cows at day 16, or pregnant at day 16 and who lost embryos by days 32. Concentrations of AOPP and TBARS were greater in nonpregnant cows at day 16 or pregnant at day 16 and who lost embryos by days 32 compared to those diagnosed pregnant at day 16 and who sustained pregnancy to day 32. In pregnant cows, endometrial mRNA expressions of MDM2, MTBP, MTR1 and LIF were higher compared to pregnant-embryo-loss cows (p < 0.05). In contrast, mRNA expressions of BBC3 and MUC1 were greater at day 16 in pregnant-embryo-loss cows compared to pregnant cows (p < 0.05). In conclusion, melatonin status is a modulator of embryo well-being and maintenance of pregnancy in lactating dairy cows.

Peripheral leucocyte molecular indicators of inflammation and oxidative stress are altered in dairy cows with embryonic loss.

Objective of experiment was to determine whether oxidative stress (OS) and inflammation altered embryonic loss in dairy cows. Blood samples were collected at days 0, 16, 32 and 60 after timed (AI) from 200 Holstein cows to determine embryonic loss based on interferon-stimulated gene-15 (ISG15) mRNA expression (day 16) and ultrasound at day 32 and day 60. Leucocyte expressions of mRNA TLR2, TLR4, TNF-α, IL1B, IL10, STAT3 (inflammation), PTGS2, PTGES (prostaglandin synthesis), and PLA2G4A and ALOX5AP (eicosanoid metabolism) at days 0 and 16 were determined. Plasma redox status for antioxidant enzymatic activities of glutathione peroxidase (GPX), superoxide dismutase (SOD), total antioxidant capacity (TAC), and concentrations of malondialdehyde (MDA) were determined at days 0, 16, 32 and 60. All antioxidant-redox responses were beneficially significant in pregnant cows diagnosed pregnant at day16 and sustained pregnancy to day 60 compared to non-pregnant cows at day16 or pregnant at day16 and lost embryos by days 32 or 60. The leucocyte mRNA expressions of TLR2, TLR4, STAT 3, IL1B, PTGS2, PLA2G4A and ALOX5AP were greater and PTGES was lower at day16 in pregnant cows that lost embryos early (P < 0.05). In conclusion peripheral leucocyte molecular indicators of inflammation and plasma indicators of OS were altered in pregnant cows undergoing embryonic losses compared to cows with a sustained pregnancy.

Effect of types of breeding on embryo survival following first AI in lactating Holstein cows.

The main objective was to investigate the effects of timed-AI protocols versus AI following oestrus detection on circulating progesterone (P4) and embryo survival after first service in Holstein cows. Cycling status was determined by ultrasonography and by plasma P4 concentrations 14 and 26 days after calving, and only cows with a corpus luteum and/or P4 ≥ 1 ng/ml were used. Cows were randomly allocated to one of three types of breeding: DO (n = 80), received GnRH-7d-PGF2α-3d-GnRH and Ovsynch56 was initiated 7 days later; G7G (n = 70), received PGF2α-2d-GnRH and Ovsynch56 (GnRH-7d-PGF2α-56h-GnRH-16h-AI) was initiated 7 days later; or AI based on oestrus detection, EDAI (n = 60). Progesterone was also determined at AI and 8, 16, 18 and 20 days after AI; ISG15 and MX2 mRNA abundance were determined 16 days after AI. Mean plasma P4 at AI was greater in the EDAI group compared with DO and G7G groups, while after AI, P4 was greater in DO and G7G groups compared with EDAI group. However, the percentage of cows with a concentration of P4 < 0.8 ng/ml at AI did not differ among groups. Relative mRNA abundance of ISG15 and MX2 was greater in the DO and G7G groups compared to those in EDAI group. Pregnancy per AI 16, 32 and 60 days after AI was greater (p < .05) in cows in the DO group compared with those in EDAI group (47.5%, 38.8% and 36.3% vs. 30.0%, 21.7% and 15.0%). Pregnancy losses between 16 and 60 days after AI were greater (p < .05) in cows in the EDAI (50.0%) group compared to those subjected to DO (23.7%) or G7G (24.1%). In conclusion, the use of timed-AI synchronization protocols resulted in greater circulating P4 concentrations post-AI and greater embryo survival following first service in lactating Holstein cows.

Antioxidant levels, copper and zinc concentrations were associated with postpartum luteal activity, pregnancy loss and pregnancy status in Holstein dairy cows.

The role of oxidative stress in the control of female reproduction has not been fully elucidated in ruminants; however, it seems that antioxidants can make influence to the reproductive axis at different levels. Therefore, the aim of this study was to determine the relationship between antioxidant status and concentrations of trace minerals (chromium (Cr), copper (Cu), iron (Fe), and zinc (Zn)) with postpartum luteal activity and fertility in Holstein dairy cows. The cows (n = 100, a parity range of 2-5, and a body condition score (BCS) of 3.0 ±â€¯0.25, mean ±â€¯SEM) were assigned to the experiment at second week post calving. Ovarian follicular dynamics were monitored twice a week (from 3rd to 6th weeks post calving) by transrectal ultrasonography (US). Blood samples were collected twice weekly from the 3rd to the 6th weeks post calving at timed artificial insemination (TAI), and days 32 and 50 post AI to determine superoxide dismutase (SOD), glutathione peroxidase (GPX), total antioxidant capacity (TAC), and trace mineral concentrations. There were associations between plasma concentrations of SOD, GPX, and TAC with postpartum luteal activity (PLA, P = 0.01) and ovulation (P = 0.03). Mean plasma SOD and GPX activities and TAC levels (U/mL) were greater in cows with normal luteal activity (NLA) than prolonged luteal phase (PLP) and anovulation (AO) cows, as well as in ovulated compared to AO cows (P = 0.03). Pregnant cows had greater levels of SOD, GPX, and TAC (U/mL) at TAI than non-pregnant cows (P = 0.01). Plasma Cu and Zn concentrations increased in pregnant compared to non-pregnant cows at TAI. In conclusion, antioxidant levels and Cu and Zn concentrations were associated with PLA and fertility.

Effects of co-incubation with conspecific ampulla oviductal epithelial cells and media composition on cryotolerance and developmental competence of in vitro matured sheep oocytes.

Developmental potential of cryopreserved in vitro matured oocytes is very low in nearly all mammalian species studied to date. Despite relatively high cleavage rates, the vitrified/warmed metaphase II oocytes have a decreased rate of blastocyst formation, which can be attributed to the elevated cytoplasmic lipid content and lipid droplet fragmentation. Secretory products of ampulla oviductal epithelial cells (AECs) at the periovulatory stage of the ovarian cycle enhance the viability of in vitro matured oocytes. The present study was undertaken to determine if co-culture of cumulus-oophorus complexes (COCs) with conspecific AECs or reducing the lipid content of in vitro matured ovine oocytes would improve their cryotolerance and ensuing developmental competence. Ovine COCs aspirated from the slaughterhouse ovaries were matured in the following media or culture conditions: TCM199 + FBS + AECs (T1); TCM199 + FBS (T2); TCM199 + BSA (T3); TCM199 + 0.6 mg/mL of l-carnitine (T4); TCM199+ l-carnitine + FBS (T5), or TCM199 only (Ctr). Subsequently, the oocytes were vitrified and used for in vitro fertilization (IVF). The lowest degree of zona pellucida (ZP) hardening following vitrification of in vitro matured sheep oocytes was observed in T1 and T5 (P < 0.05). Cleavage, blastocyst formation and ensuing development (i.e., total cell numbers) as well as blastocyst hatching rates were all greater (P < 0.05) in T1 compared with the remaining groups; in vitro matured COCs in T4 and Ctr did not develop beyond the cleavage stage. The inner cell mass: trophectoderm cell ratio in T1 (1:3.29) was significantly greater compared with T2 (1:3.39), T3 (1:3.40) and T5 (1:3.44). The present results indicate that the ovine COCs/AECs co-culture system had the most positive influence on cryotolerance, ZP hardening, and developmental competence of in vitro matured oocytes.

Effect of Exogenous Progesterone or Flunixin Meglumine After AI on Serum Progesterone Concentration and Pregnancy per AI in Lactating Dairy Cows.

The objective of this study was to determine the effect of post AI administration of exogenous progesterone (P4) or a prostaglandin F2α (PGF2α) synthesis inhibitor agent on serum P4 concentrations and pregnancy per AI (P/AI) in lactating dairy cows. Eighty lactating cows were randomly allocated to one of four treatment groups: 1) CON (control), received 5 mL of saline solution on d 6 and 14 post AI; 2) IP4 (injection of P 4), received 125 mg of P4 im on d 6 and 14 post AI; 3) CIDR, received a controlled internal drug release insert containing 1.38g of P4 from d 6 to 20 post AI; and 4) FM (Flunixin Meglumine), received 0.625 g of Flunixin Meglumine, a nonsteroidal anti-inflammatory drug, twice daily on d 15 and 19 post AI. Blood samples were taken on d 0, 6, 14, 17 and 20 post AI to determine P4 concentrations. Transrectal palpation was performed between 40 and 45 d post AI to determine pregnancy status. All treatment groups (i.e. IP4, CIDR and FM) resulted in greater serum P4 concentration on d 17 and 20 post AI compared to CON (P < 0.05). Cows given a CIDR insert had greater concentrations of P 4 on d 17 and 20 than IP4 and FM cows (P < 0.05). However, no significant difference was found between IP4 and FM groups for serum P4 concentrations. The P/AI was greater (P < 0.05) in CIDR-treated cows (55%, 11/20) than CON (25%, 5/20), and intermediate in IP4 (40%, 8/20) and FM (35%, 7/20) cows. In summary, treatment with exogenous P4 (i.e. CIDR and IP4) or FM increased serum P4 concentrations in lactating dairy cows. However, results suggest that only CIDR administration would improve P/AI.

The role of fibroblast growth factor-18 in follicular atresia in cattle.

Although the various members of the fibroblast growth factor (FGF) family are generally mitotic, one member, FGF18, has been shown to increase the rate of apoptosis of ovarian granulosa cells. In the present study, we first determined whether granulosa cells express FGF18 and we then explored the mechanism through which FGF18 increases apoptosis in vitro. Under culture conditions that favored estradiol secretion and CYP19A1 expression, granulosa FGF18 mRNA levels were barely detectable; however, withdrawing gonadotropic support (follicle-stimulating hormone or insulin-like growth factor 1) reduced levels of CYP19A1 mRNA and increased abundance of mRNA encoding the death ligand FASLG and FGF18. Addition of FGF18, but not FGF2, FGF10, or EGF, increased the proportion of apoptotic cells and frequency of caspase 3 activation, and these effects were abrogated by coculture with estradiol. Addition of FGF18 decreased abundance of mRNA encoding the antiapoptotic proteins GADD45B and MDM2, and increased that encoding the proapoptotic protein BBC3; these effects were reversed by coculture with estradiol. The physiological relevance of FGF18 was determined using an in vivo model: injection of FGF18 directly into growing bovine dominant follicles caused cessation of follicle growth by 24 h after injection. Collectively, these data demonstrate that FGF18 is proapoptotic in vivo and may act through a mechanism involving the BBC3-MDM2 pathway.

Nutritive value of some herbage for dromedary camels in the central arid zone of Iran.

The purpose of this study is to prepare standard tables of the chemical composition of feedstuff and to determine the digestibility and palatability of different plant species in the dromedary camel, this research was conducted considering the consumed herbages by camels in the central arid zone of Iran. The following plant species were included: Alhagi camelorum, Artemisia sieberi, Atriplex lentiformis, Haloxylon persicum, Hammada salicornica, Salsola tomentosa, Salsola rigida, Seidlitzia rosmarinus, Suaeda fruticosa, Tamarix tree, and Tamarix kotschi. Thirty samples of the browsing parts were collected from three sites in the rangelands of Qom and Yazd province. The chemical composition of the samples, including dry matter, crude protein (CP), crude fiber, neutral detergent fiber (NDF), acid detergent fiber (ADF), ether extract, total ash, macroelements (Ca, P, Mg, K), microelements, and gross energy were measured. The in vitro digestibility of the plants was measured by camel liquor using the Tilley and Terry method. The palatability of the plants was measured by four mature camels in cafeteria trials. Data were analyzed by general linear model method using the SAS software. The highest CP (17.5%) related to Haloxylon persicum and the lowest NDF (26.2%) and ADF (12.6%) were related to Salsola rigida. The lowest CP (5.5%) and the highest NDF (72.8%) and ADF (59.6%) were related to Artemisia sieberi. The results also indicate that Atriplex lentiformis, Alhagi camelorum, Seidlitzia rosmarinus, Suaeda fruticosa, Haloxylon persicum, Salsola tomentosa, Hammada salicornica, T. kotschi, Salsola rigida, Tamarix tree, and Artemisia seiberi were more pleasurable feeds, respectively. There was no consistent relationship between the palatability of herbages with the percentage of digestible organic matter in the dry matter or chemical composition.