Chemical composition, in vitro digestibility and palatability of nine plant species for dromedary camels in the province of Semnan, Iran

This work studied the chemical composition of plants, and their digestibility and palatability to camels, selecting plants most eaten by camels from the Iranian desert of the province of Semnan. The results indicated that the order of usefulness, from the most useful, was: Salsola arbuscula, Seidlitzia rosmarinus, Suaeda fruticosa, Alhagi camelorum, Haloxylon ammodendron, Halostachys spp., Tamarix tetragyna, Tamarix stricta and Hammada salicornica. No correlation was detected between the organic matterdigestibility in dry matter and chemical composition, and there was no consistent relationship between either of these variables and palatability

Course correction: the role of reflective writing assessment in a post-pandemic academic literacy course

In this conceptual paper, borne from the experiences of two ccademic literacy lecturers at the NWU, we ask, regarding elements of assessment, how we can sensibly adapt an intervention-style writing course in a post-Covid higher education context. We propose a course correction model, applicable to academic literacy writing courses, to address the pedagogical lacunae highlighted in a pre-pandemic context and compounded in the post-pandemic higher education context. We argue for the adaption of this writing course to contend with the under-preparedness of students for higher education, the issue of online learning and resultant student cognitive overload and additional challenges, such as the rapid development of AI and its effects on teaching and learning, and specifically writing courses. An important element which needs to be reconceptualised within the context of our compounded problem, is that of the writing assessment. In this paper we argue for moving away from placing major emphasis on assessing the final product of writing and shifting some focus to the pedagogical value of examining the student’s journey of writing. We therefore propose incorporating reflective writing as a significant element of assessment through our reflect-rewrite-model. The goal of this proposed model is to create a space for fostering student self-awareness, responsibility, critical thinking, and evaluation skills. Such outcomes should then contribute to the creation of effective and contextually relevant, academic skills development, which in turn should positively influence student success and mitigate some of the issues currently experienced in the module offering

Effect of plasmin and heparin on in vitro ovine spermoocyte interaction

This study was conducted to investigate the effect of plasmin and heparin on in vitro ovine spermoocyte interaction. Different concentrations of plasmin (0, 1, 10, 100 ng/ml) and heparin (0, 5, 10 IU/ml) were added alone or simultaneously into fertilization medium. After sperm and oocyte co-culture, binding and penetration of sperm to zona pellucida (ZP) were assayed. Treatment with 1 and 10 ng/ml plasmin resulted in higher sperm binding to ZP than those in control. The rates of sperm binding to ZP were increased with highest heparin concentrations (10 IU/ml). Heparin had no effect on penetration rate of sperm to ZP. Simultaneously effects of plasmin and heparin were not significant on penetration rate of sperm to ZP. But, 5 or 10 IU/ml heparin in the present of 1 ng/ml plasmin had higher effect on sperm binding to ZP than that in the other groups. These results suggest that plasmin and heparin (alone/simultaneously) might play a role in events related to fertilization in ovine

Quantification of the uterine involution and dimensions, hormonal response and reproductive performance of pyometric and healthy dairy cows treated with Dinoprost

The aim of the present study was to investigate the effects of a PGF2α analogue (Dinoprost) on involution of the puerperal uterus, especially with pyometra during 35 to 45 days postpartum in multiparous high yielding Holstein dairy cows. At days 40 ± 5 postpartum, 1250 cows were ultrasonographically examined. Fifty cows were diagnosed as pyometric. Fifty pyometric and 50 clinically healthy cows were assigned randomly to one of four groups. Groups were: 1.) Pyometric+Dinoprost cows (PD, n = 25 treated with 25 mg of Dinoprost), 2.) Pyometric+Saline cows (PS, n = 25 treated with saline), 3.) Healthy+Dinoprost cows (HD, n = 25 treated with 25 mg of Dinoprost), and 4.) Healthy+Saline cows (HS, n = 25 treated with saline). All treatments were given intramuscularly. Ultrasonography was performed at the time of examination and 7 days later to evaluate changes in uterine diameter. Treatment with Dinoprost significantly reduced gross uterine diameter in PD in comparison to the PS group in the presence or absence (P4 concentrations <1 ng/ml) of an active corpus luteum. Dinoprost treatment did not decrease gross uterine diameter in groups HD and HS. Luminal diameter was significantly smaller in the PD than in the PS group. Pregnancy rate of PD was greater than PS cows (36% vs 20%, respectively). Days to first service (110 d vs. 140 d) and open days (160 d vs. 190 d) were shorter in PD cows than PS cows. It was concluded that injection of 25 mg of Dinoprost to pyometric cows had uterotonic effects in presence or absence of functional corpus luteum. Therefore, this treatment can help uterine involution in puerperal dairy cows affected by pyometra and consequently improved reproductive performance.Keywords: Cattle, Dinoprost, pregnancy rate, pyometra, uterine healt

Scattering functions of knotted ring polymers

We discuss the scattering function of a Gaussian random polygon with N nodes under a given topological constraint through simulation. We obtain the Kratky plot of a Gaussian polygon of N=200 having a fixed knot for some different knots such as the trivial, trefoil and figure-eight knots. We find that some characteristic properties of the different Kratky plots are consistent with the distinct values of the mean square radius of gyration for Gaussian polygons with the different knots.Comment: 4pages, 3figures, 3table

Trehalose and glycerol have a dose-dependent synergistic effect on the post-thawing quality of ram semen cryopreserved in a soybean lecithin-based extender

P. 275-282The objective of this study was to examine the interaction of different concentrations of trehalose [0 (T0), 50 (T50) or 100 (T100) mM] and glycerol [5% (G5) or 7% (G7)] on post-thawed quality of ram semen, cryopreserved in a soybean lecithin (SL)-based extender. Twenty-eight ejaculates were collected from four rams and diluted with six trehalose/glycerol combinations: T0G5, T50G5, T100G5, T0G7, T50G7, and T100G7. Sperm motility (CASA), membrane integrity (eosin/nigrosin) and functionality (HOST), abnormal forms, capacitation status (CTC), mitochondrial activity (rhodamine 123), apoptotic features (Annexin V/propidium iodide) and lipoperoxidation (malondialdehyde production) were evaluated after thawing. Extender T100G5 yielded the highest results for total and progressive motility, sperm velocity, normal morphology, functional membranes, active mitochondria and membrane integrity, with P 0.05). The combinations T0G5, T0G7 and T100G7 yielded the lowest post-thaw quality. We could not detect significant changes in other kinematic parameters, capacitation status or lipoperoxidation. We conclude that, in our SL-based extender, a combination of 100 mM trehalose and 5% glycerol was the most adequate combination to achieving post-thawing quality in our soybean lecithin-based extender, and our results support that a synergistic effect among trehalose and glycerol exists. We suggest that other combinations could improve these results.S

Effect of glucose, lactate and pyruvate concentrations on in vitro growth of goat granulosa cell

Carbohydrates are among the most influential of the numerous components of culture medium that affect metabolism and developmental potential. Glucose, lactate and pyruvate are required for the growth of oocytes and other follicular cells in vitro. The aim of this study was to determine the effects of different concentrations of glucose, lactate and pyruvate on promoting DNA synthesis of granulosa cells in a serum-free medium. Effects of glucose (0.75, 1.5 or 3 mM), pyruvate (0.1 or 0.33 mM) and Llactate (3, 6 or 12 mM) concentrations in the maturation medium on the relative granulosa cell growth during metaphase II (MII) were examined in a 3 × 2 × 3 factorial design. The greatest relative granulosa cell growth response (p<0.05) was observed in the presence of 1.5 mM glucose and 0.33 mM pyruvate or in 6 mM lactate and 0.33 mM pyruvate. Increasing pyruvate concentrations from 0.1 to 0.33 mM resulted in an increase in DNA synthesis in granulosa cells. In conclusion, the results of this study showed that increasing glucose and pyruvate concentrations in the maturation medium increased the growth of goat granulosa cells.Key word: Energy substrate, granulosa cell growth, methyl-3H-thymidine, goat

Effect of oral administration of pioglitazone on follicular dynamics in Holstein dairy cows

This study investigated the effects of oral administration of pioglitazone (PGT), a specific and synthetic ligand of peroxisome proliferator-activated receptors gamma (PPARγ), on follicular dynamics and corpus luteum (CL) functionality in dairy cows. Cows exhibiting strong signs of estrus after 2 injections of PGF2α (given14 d apart) at d 30 postpartum (n = 28) were allotted to four groups (n = 7 cows/treatment) and orally received 6 mg PGT/kg body weight/day according to the following protocol: no PGT (control); PGT for 14 d from 7 d before expected estrus (10 d after 1st injection of PGF2α) to 7 d after observed estrus (PGT14); PGT for 21 d after observed estrus (PGT21); and PGT for 28 d, 7 d before expected estrus to 21 d after observed estrus (PGT28). During the first follicular wave, number of follicles (total and small) increased in PGT14 and PGT28 cows compared to the control group (P < 0.05). During the ovulatory wave, number of total and small follicles increased in PGT28 (P < 0.05) and PGT21 (P < 0.10) compared with PGT14 and control cows. Size of the largest follicle at first wave was greater in PGT28 (P < 0.05), PGT14 (P < 0.05) and PGT21 (P < 0.10) compared to the control cows. Maximal size of the ovulatory follicle was greater in PGT28 (P < 0.05) and PGT21 (P < 0.10) groups compared to the control group. Growth rate of the largest follicle at first wave was higher (P < 0.05) in PGT-treated cows, while growth rate of the ovulatory wave was higher in PGT28 and PGT21 groups, leading to shorter days from luteolysis to ovulation. Pioglitazone administration did not affect CL size, but increased progesterone (P4) concentration. The PGT14 and PGT28 cows had higher maximal plasma P4 concentration and shorter intervals to reach maximal plasma P4 compared to the control group. In conclusion, oral administration of PGT had some positive effects on follicular development and circulating P4 levels which may be conducive to better reproductive performance

Phosphorylation and modulation of hyperpolarization-activated HCN4 channels by protein kinase A in the mouse sinoatrial node

The sympathetic nervous system increases heart rate by activating β adrenergic receptors and increasing cAMP levels in myocytes in the sinoatrial node. The molecular basis for this response is not well understood; however, the cardiac funny current (If) is thought to be among the end effectors for cAMP signaling in sinoatrial myocytes. If is produced by hyperpolarization-activated cyclic nucleotide–sensitive (HCN4) channels, which can be potentiated by direct binding of cAMP to a conserved cyclic nucleotide binding domain in the C terminus of the channels. β adrenergic regulation of If in the sinoatrial node is thought to occur via this direct binding mechanism, independent of phosphorylation. Here, we have investigated whether the cAMP-activated protein kinase (PKA) can also regulate sinoatrial HCN4 channels. We found that inhibition of PKA significantly reduced the ability of β adrenergic agonists to shift the voltage dependence of If in isolated sinoatrial myocytes from mice. PKA also shifted the voltage dependence of activation to more positive potentials for heterologously expressed HCN4 channels. In vitro phosphorylation assays and mass spectrometry revealed that PKA can directly phosphorylate at least 13 sites on HCN4, including at least three residues in the N terminus and at least 10 in the C terminus. Functional analysis of truncated and alanine-substituted HCN4 channels identified a PKA regulatory site in the distal C terminus of HCN4, which is required for PKA modulation of If. Collectively, these data show that native and expressed HCN4 channels can be regulated by PKA, and raise the possibility that this mechanism could contribute to sympathetic regulation of heart rate