Effect of recombinant human follicle-stimulating hormone and luteinizing hormone on in vitro maturation of porcine oocytes evaluated by the subsequent in vitro development of embryos obtained by in vitro fertilization, intracytoplasmic sperm injection, or parthenogenetic activation

The aim of this work was to study the effect of recombinant human (rh) FSH and LH on in vitro maturation of pig oocytes compared with a conventional hormonal supplement based on equine (PMSG) and human chorionic gonadotropins (hCG), as evaluated by the developmental ability of 3 types of pig embryos obtained by in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), or artificial activation (ATA). In Exp. 1, one cumulus-oocyte complex group (A group) was supplemented with rh-FSH and rh-LH (0.1 IU/mL each), and the other group (B group) was supplemented with PMSG and hCG (10 IU/mL each). No differences in nuclear maturation between the A and B groups were observed (68.5 vs. 71.4%, respectively). No differences were detected between hormonal treatments in the rates of cleavage or blastocyst formation of ATA, IVF, and ICSI embryos. Total cell number of the embryos was not significantly different in any experimental group (A: 31.1, 28.5, and 19.8 vs. B: 25.2, 25.5, and 20.6 for ATA, IVF, and ICSI embryos, respectively). In Exp. 2, the effects of different concentrations of rh-FSH and rh-LH (0.5, 0.1, or 0.05 IU/mL) in maturation medium on nuclear maturation and in vitro development of embryos obtained by IVF were studied. No effect of different hormonal concentrations on blastocyst formation rates was observed (8.5, 13.0, and 5.7%, respectively). Blastocyst cell number was not different in any experimental group. In conclusion, the results obtained here permit us to substitute PMSG and hCG with rh-FSH and rh-LH and to produce pig embryos obtained by IVF, ICSI, or ATA.     

Avian regulation of crop and forest pests,a meta-analysis

BACKGROUND

Birds have been shown to reduce pest effects on various ecosystem types. This study aimed to synthesize the effect of birds on pest abundance, product damage and yield in agricultural and forest systems in different environments. Our hypothesis is that birds are effective pest regulators that contribute to a reduction in pest abundance, enhancement of yield quality and quantity and economic profit, and that pest regulation may depend on moderators such as the type of ecosystem, climate, pest, and indicator (ecological or economic).

RESULTS

We performed a systematic literature review of experimental and observational studies related to biological control in the presence and absence of regulatory birds. We retained 449 observations from 104 primary studies that were evaluated through qualitative and quantitative analyses. Of the 79 studies with known effects of birds on pest regulation, nearly half of the 334 observations showed positive effects (49%), 46% showed neutral effects, and very few (5%) showed negative effects. Overall effect sizes were positive (mean Hedges’ d = 0.38 ± 0.06). A multiple model selection retained only ecosystem and indicator types as significant moderators.

CONCLUSION

Our results support our hypothesis that there is a positive effect of avian control of pests for each analyzed moderator and this effect was significant for both ecological and economic indicators. Avian regulation of pests is a potential effective approach for environmentally friendly pest management that can reduce pesticide use regardless of the context of implementation. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

Irrigation scheduling for traditional,low-density olive orchards: Water relations and influence on oil characteristics

An experiment was performed in a low-density olive orchard (69 trees ha⁻¹) to study the recovery from water stress of olive trees under different irrigation managements. The effect of water stress on oil quality was also examined. The trees were subjected to one of four irrigation treatments: rain-fed conditions, irrigation with either 100% or 125% of the crop evapotranspiration (ET_c) level, or a deficit treatment in which only 60 mm of water were provided (at different times depending on the weather and phenological stage of the crop). The irrigation water in the deficit treatment was some 43% of the water applied in the 125% treatment. Plant water relations were determined periodically by measuring the water potential of covered leaves and the stomatal conductance at midday. The trees in the water deficit and rain-fed treatments rapidly recovered from water stress after receiving irrigation water or autumn rainwater, respectively, reaching the condition of the fully irrigated trees. However, stomatal conductance took longer to recover. Recovery at mid-summer in the deficit treatment was related to the amount of water in the soil; in autumn, however, this relationship was not so clear in rain-fed trees. The effect on oil quality was recorded in terms of the total concentration of phenolic compounds (TP). This was strongly related to the water stress integral, suggesting that the effect of irrigation on this variable occurs year-round and not just during the oil accumulation phase. Thus, even with low doses of water it should be possible to significantly reduce the TP concentration. Since recovery from water stress is rapid when irrigation is concentrated in the second half of summer, such an irrigation regimen might allow efficient use of the limited amounts of water available in central Spain.     

Largazole Pharmacokinetics in Rats by LC-MS/MS

A highly sensitive and specific LC-MS/MS method for the quantitation of largazole thiol, the active species of the marine-derived preclinical histone deacetylase inhibitor, largazole (prodrug), was developed and validated. Largazole thiol was extracted with ethyl acetate from human or rat plasma along with the internal standard, harmine. Samples were separated on an Onyx Monolithic C18 column by a stepwise gradient elution with 0.1% formic acid in methanol and 0.1% aqueous formic acid employing multiple reaction monitoring (MRM) detection. Linear calibration curves were obtained in the range of 12.5–400 ng/mL with 200 µL of human plasma. The overall intra-day precision was from 3.87% to 12.6%, and the inter-day precision was from 7.12% to 9.8%. The accuracy at low, medium and high concentrations ranged from 101.55% to 105.84%. Plasma protein bindings of largazole thiol in human and rat plasma as determined by an ultrafiltration method were 90.13% and 77.14%, respectively. Plasma drug concentrations were measured by this LC-MS/MS method. The pharmacokinetics of largazole thiol in rats was studied following i.v. administration at 10 mg/kg and found to follow a two-compartment model. Largazole thiol was rapidly eliminated from systemic circulation within 2 h. The established LC-MS/MS method is suitable for the analysis of largazole thiol in human plasma, as well.     

Determination of the secondary structure of Kluyveromyces lactis beta-galactosidase by circular dichroism and its structure-activity relationship as a function of the pH

The secondary structure of Kluyveromyces lactis beta-galactosidase was determined by circular dichroism. It is mainly a beta-type protein, having 22% beta-turns, 14% parallel beta-sheet, 25% antiparallel beta-sheet, 34% unordered structure, and only 5% alpha-helix. The structure-activity relationship as a function of the pH was also studied. The pH conditions leading to the highest secondary structure content (100% ellipticity) of the enzyme was found at pH 7.0; at pH 6.5-7.0, the percent ellipticity decreased slightly, suggesting little structural change, but the activity decreased significantly, probably because of variations in critical residues. On the other hand, at pH's above 7.0, a more noticeable change in ellipticity was observed due to structural changes; the CD analysis showed a small increase in the helical content toward higher pH, whereas the maximum activity was found at pH 7.5, meaning that the changes produced in the secondary structure at this pH favored the interaction between the enzyme and the substrate.     

Contribution of Mycorrhizae to Early Growth and Phosphorus Uptake by a Neotropical Palm

Arbuscular mycorrhizal fungi (AMF) can act as an extension of the root system of their host plants. In Desmoncus orthacanthos Martius (Arecaceae), which has thick and unbranched roots (i.e., magnolioid roots) and low densities of root hairs, this association may be essential to reach a maximum growth with minimum fertilizers. This is important because of the potential in the south of Mexico to use D. orthacanthos' shoots as a raw material to build handcrafts. To evaluate the effect of arbuscular mycorrhizae on phosphorus (P) uptake and initial growth of D. orthacanthos seedlings, a 160-day bi-factorial experiment was carried out in which plants were subject to one of two levels of mycorrhizal colonization (with or without) and one of three levels of P substrate addition (4, 12, and 24 ppm). Our results show that total dry weight (DW) and leaf area (LA) responded significantly to P addition but not to mycorrhizal colonization. Phosphorus concentration in plant tissues (Pt) was increased by both factors (mycorrhizae and P addition). Mycorrhizae increased relative growth rate (RGR) at low P level. Our results indicate that AMF play an important role in early growth and P uptake by D. orthacanthos seedlings; therefore, the AMF must be considered in plantations of this potentially economically important palm.     

Adaptation of ostriches to transport‐induced stress: Physiometabolic response

This study assessed the effects of five different transport periods on physiometabolic responses and gas exchange in ostriches. It included 138 ostriches that were assigned to five experimental groups. G₁ included 78 birds that were set aside as a reference group (RG). Each one of the four remaining experimental groups included 20 ostriches, which were transported in the following manner: G₁ on one occasion for a period of 1 h; G₂ on one occasion for 2 h; and G₃ on one occasion for 3 h; G_4a was made up of the ostriches from G₁ but they were shipped on a second occasion, for 2 h (making a total of 3 h); finally, G_4b was that same group, but after a third transport period, on this occasion during 3 h (for a total of 6 h). Groups G₂ and G₃ presented the most marked blood alterations (P < 0.05), including an increase in pH, hypocapnia (27.8 ± 0.80 mmHg), hypernatremia (171.75 ± 1.84 mmol/L), hypocalcemia (0.95 ± 0.03 mmol/L), and hyperglycemia (224.05 ± 3.94 mg/dL). Also, group G₃ presented the lowest hematocrit values (26.5 ± 0.47 HTC%). Therefore, transporting ostriches with no prior experience for 3 h caused the most pronounced physiometabolic changes.     

Influence of food deprivation and high stocking density on energetic metabolism and stress response in red porgy, Pagrus pagrus L

In the present study, the influence of high stocking density and food deprivation on red porgy (Pagrus pagrus L.) energy metabolism was investigated after 14 and 21?days assessing plasmatic, hepatic, and muscular parameters. Specimens were submitted to four different experimental conditions: (1) fed fish under low stocking density (4?kg?m^?3, LSD-F); (2) food-deprived fish under low stocking density (LSD-FD); (3) fed fish under high stocking density (50?kg?m^?3, HSD-F); and (4) food-deprived fish under high stocking density (HSD-FD). At plasmatic level, cortisol concentration enhanced in fish maintained under HSD condition, with higher effect in fed fish, whereas FD condition decreased values of lactate, protein, and triglycerides. In liver, significant increases in triglyceride levels, together with a decrease in glycogen values, were observed in FD specimens. Furthermore, a weak effect of density in fed fish was observed, with decreasing hepatic glycogen. In white muscle, aminoacid and triglyceride values diminished in FD group, while increased in specimens submitted to HSD condition. Our results suggested an enhancement in P. pagrus gluconeogenic and glycogenolytic potential when submitted to HSD and FD conditions to cope reallocation of metabolic energy due to these different stress situations.