Fertilizer Trials Research Articles

Acupuncture for the treatment of diminished ovary reserve

ObjectiveTo share 20 cases of women with diminished ovary reserve (DOR) and low Anti-Müllerian Hormone (AMH), who had unsuccessful in-vitro fertilization (IVF) trials and to whom the author has successfully treated. MethodsTwenty women with DOR had gone through the failed IVF from 1 to 5 times. The acupuncture protocol consists of electroacupuncture, manual acupuncture, acupressure and sliding-cupping, which are the multiple interventions. The acupoints were used based on 5 phases of the menstrual cycle. The electroacupuncture was used twice a week in the follicle phase and the acupuncture without the electricity was used once a week in the luteal phase. Most of them had been treated for three menstrual cycles. ResultsAll of 20 women got pregnant by IVF (17 casese) or naturally (3 cases). ConclusionAcupuncture might improve IVF outcomes for women with DOR by acupuncture treatment for three months or help them to receive naturally.

Soil fertility regulates invasive herbivore performance and top-down control in tropical agroecosystems of Southeast Asia

Abstract In terrestrial ecosystems, changes in soil nutrient availability, plant growth or natural enemies can generate important shifts in abundance of organisms at various trophic levels. In agroecosystems the performance of (invasive) herbivores and their impacts on crops is of particular concern. Scientists are presently challenged with making reliable inferences on invader success, natural enemy performance and efficacy of biological control, particularly in tropical agroecosystems. In this study, we assess how trophic regulatory forces (bottom-up vs. top down) influence the success of three globally important pests of cassava. We examine the mealybug species (Hemiptera: Pseudococcidae) of differing host breadth and invasion history: Phenacoccus manihoti, Paracoccus marginatus, and Pseudococcus jackbeardsleyi. Potted plant fertilizer trials were combined with a regional survey in Vietnam, Laos and Cambodia of 65 cassava fields of similar size and age, but with varying soil fertility. Relative abundance of each mealybug invader was mapped along a soil fertility gradient, and contrasted with site-specific measures of parasitism. Potted plant trials revealed strong bottom-up effects for P. manihoti, such that impacts of nitrogen and potassium additions were propagated through to higher trophic levels and substantially boost development and fitness of its specialist parasitoid, Anagyrus lopezi (Hymenoptera: Encyrtidae). Field surveys indicate that mealybug performance is highly species-specific and context-dependent. For example, field-level abundance of P. jackbeardsleyi and P. marginatus, was related to measures of soil fertility parameters, soil texture and plant disease incidence. Furthermore, for P. manihoti, in-field abundance is equally associated with soil texture (i.e., silt content). Principal component analysis (PCA) and regression suggested that P. manihoti and P. marginatus are disproportionately favored in low-fertility conditions, while P. jackbeardsleyi prospers in settings with high organic carbon and phosphorus. Parasitism of P. manihoti by A. lopezi varied greatly with field and soil fertility conditions, and was highest in soils with intermediate fertility levels and where management practices include the addition of fertilizer supplements. Our characterization of the relative performance of invasive mealybugs and strength of parasitism across variable soil fertility conditions will help guide parasitoid release programs and soil management practices that enhance mealybug biological control.

Clinical trial registration in fertility trials - a case for improvement?

What is the prevalence and source of prospectively and retrospectively registered and unregistered trials in fertility treatments? Trial registration is low and does not appear to be changing over the 5 years studied. Trial registration is associated with lower risk of bias than in unregistered trials. The Cochrane Gynaecology and Fertility Group's specialised register was searched on 5 November 2015 for randomised controlled trials (RCTs) published from January 2010 to December 2014. Eligible trials included randomised women or men for fertility treatments, were published in full text, and written in English. Two reviewers independently assessed trial registration status for each trial, by searching the publication, trial registries, and by contacting the original authors. Of 693 eligible RCTS, only 44% were registered trials. Of 309 registered trials, 21.7% were prospectively registered, 15.8% were registered within 6 months of first patient enrolment and 62.5% were retrospectively registered trials. Prospective trial registration by country varied from 0% to 100%. The highest frequency of prospective trial registration amongst the top 10 publishing countries was 31% in the Netherlands. Only English language trials were included in this review. Prospective trial registration is still low. Journals, funders and ethics committees could have a greater role to increase trial registration. University of Auckland. No competing interests.

In‐Season Estimation of Corn Yield Potential Using Proximal Sensing

Core Ideas Accurate yield prediction is needed for effective sensor‐based N management. Field testing is needed to develop reliable algorithms for silage and grain corn. For the most accurate yield prediction, crop sensing should be done at V6 or later. Predictions for corn silage were more accurate than for corn grain. The use of in‐season‐estimated yield is preferred across variable sites. Crop sensing is a promising approach for predicting corn (Zea mays L.) yield. Yield prediction is the first step in development of algorithms for sensor‐based N management. Here, we evaluated the impact of (i) timing of sensing (growth stage), and (ii) method of reporting sensor data on estimations of corn grain and silage yield in New York. Sensor data were reported as the normalized difference vegetation index (NDVI), in‐season estimated yield (INSEY) expressed as NDVI divided by days after planting (DAP; INSEYDAP), growing degree days (GGD; INSEYGGD), and the inverse simple ratio (ISR; [1–NDVI]/[1+NDVI]) divided by DAP (INSEYISR). To evaluate timing of sensing, corn of six fertility trials was scanned at every growth stage between V4 and V11. The replicated trials had up to six N rates (0, 56, 112, 168, 224, and 336 kg ha−1). The V7 sensor and yield data from zero‐N plots of nine additional on‐farm trials (varying histories) were added to derive yield algorithms for New York. Drought at three sites in 2016 negatively impacted the accuracy of sensor‐based grain yield estimates (R2 < 0.27). Excluding these sites, most accurate yield predictions were obtained from V6 onward. Across different locations and independent of reporting method, INSEY data at V7 predicted yield with an R2 > 0.70 (grain) and >0.77 (silage). We conclude that INSEY data obtained at V7 can be used to accurately predict corn grain and silage yields in non‐drought conditions in New York.

Non-publication and publication bias in reproductive medicine: a cohort analysis.

Does publication bias or non-publication exist in fertility trials presented as conference abstracts? This study did not detect any publication bias; however, it did identify a high level of non-publication, with only 49% of abstracts reaching full-text publication four or more years after abstract presentation. Systematic reviews of randomized controlled trials (RCTs) are the foundation of evidence based medicine. Non-publication or publication deficit refer to the failure to publish trial results. A publication bias exists when there is any tendency on the parts of the investigators or editors to fail to publish study results on the basis or strength of the study findings. Both present a serious problem for researchers, clinicians and policymakers alike, and ultimately impact on patient care. A retrospective cohort study identified 337 fertility RCTs presented as conference abstracts between 2007 and 2010, as captured by an electronic search of the Cochrane Gynaecology and Fertility Database. After excluding ineligible trials and duplicates, 224 abstracts remained. A search for the full-text papers of each abstract was undertaken in Pubmed, MEDLINE, Embase, CINAHL and Google in May 2015 using a probabilistic approach. Trial authors were contacted to query the publication status of abstracts when no full-text was identified. The association between individual variables and the probability of publication, and time to publication, was assessed using logistic regression and Cox regression, respectively. Of the 224 included abstracts, only 110 (49%; 95% CI: 42.6, 55.6) were found to be published as full-text articles. Publication bias was not identified in this cohort; studies with positive results had a similar probability of reaching full-text publication 52/113 (46%; 95% CI: 37.0, 55.3) as studies with non-positive (negative or null) results 58/111 (52%; 95% CI: 17.8, 33.9) (adjusted odds ratio (AOR): 1.02; 95% CI: 0.53, 1.97). Similarly, the time from abstract presentation to full-text publication was similar in studies with positive and non-positive results. Oral presentations were more likely to be published, and to be published sooner, than poster presentations (poster presentation AOR: 0.31; 95% CI: 0.15, 0.61 and adjusted hazard ratio (AHR): 0.57; 95% CI: 0.38, 0.86). Studies that were not registered were less likely to be published and to have delayed publication, than studies which were registered either prospectively or retrospectively (AOR: 0.14; 95% CI: 0.04, 0.44 and AHR: 0.43; 95% CI: 0.25, 0.72). Abstracts which were presented a longer time ago also had a higher probability of reaching full-text publication (P = 0.01). Commencing with a cohort of RCTs from ethics committee registers may provide a better picture of the extent of non-publication and publication bias, as not all trials reach the stage of abstract presentation. It is also possible that the search did not identify all published trials, as some may have been published after the follow-up period. This study did not identify any publication bias. However, only half of the abstracts in this cohort have been published as full-text articles, four or more years after their presentation at a conference. This is similar to publication rates reported previously for fertility trials, and is despite increasing awareness of the importance of publishing trial results, and subsequent requirements for all RCTs to be registered prior to trial initiation. A better understanding of the reasons for non-publication should assist in facilitating the prompt full-text publication of RCTs in the future. Funding provided from the University of Auckland. All authors declare they have no conflicts of interest in relation to this article. Not applicable.

Effects of age on the reproductive performance of different males and females in bighead carp Hypophthalmichthys nobilis (Richardson, 1845)

The age of fish can affect reproductive performance in relation to the gamete quality and productivity which might be expected to be changed in older individuals. The consideration can be important in artificial propagation in relation to the selection of broodstock. We determined the age-related changes in male and female reproductive characteristics of the bighead carp Hypophthalmichthys nobilis and then we examined the effects of age on the male and female reproductive fitness in terms of fertilization, hatching, and larvae survival rate. A total of eight 3–4-year-old males and eight 4–5-year-old females were crossed using a factorial breeding design. Fertilization, hatching, and larvae survival rates were counted. We found no significant difference between 3 and 4 year olds in the sperm motility traits, density, and spermatocrit, but significant differences (p < 0.05) were observed in the ionic composition (mainly Na+, K+, Ca2+, Mg2+), acid phosphatase, and glucose level. The quantitative characteristics between two age groups (4 and 5-year-olds) of the females showed significant differences (p < 0.05) in total weight of stripped egg, ovarian weight, and relative fecundity, while no significant differences were found in egg size, absolute fecundity, and gonadosomatic index (GSI). In fertilization trials, we found that male age strongly influences fertilization (p < 0.05), embryonic development (p < 0.05), and larval survivability (p < 0.001), while significant female effects, as well as male and female interactions (p < 0.001 for all) were only observed for 7 days post-hatching larval survivability. One-way ANOVA showed significant differences among the fertilization (F = 3.797, p = 0.05), hatching (F = 4.802, p = 0.03), and larvae survival rate (F = 32.94, p = 0.001). Our results suggest that crosses between 4-year-old males and 5-year-old females of bighead carp achieved the best reproductive output.

Phosphorus Over-Fertilization and Nutrient Misbalance of Irrigated Tomato Crops in Brazil.

Over the past 20 years, the use of center-pivot irrigation has increased tomato (Solanum lycopersicum L.) yields in Brazil from 42 Mg ha−1 to more than 80 Mg ha−1. In the absence of field trials to support fertilizer recommendations, substantial amounts of phosphorus (P) have been applied to crops. Additional P dosing has been based on an equilibrated nutrient P budget adjusted for low-P fertilizer-use efficiency in high-P fixing tropical soils. To document nutrient requirements and prevent over-fertilization, tissue samples and crop yield data can be acquired through crop surveys and fertilizer trials. Nevertheless, most tissue diagnostic methods pose numerical difficulties that can be avoided by using the nutrient balance concept. The objectives of this study were to model the response of irrigated tomato crops to P fertilization in low- and high-P soils and to provide tissue diagnostic models for high crop yield. Three P trials, arranged in a randomized block design with six P treatments (0–437 kg P ha−1) and three or four replications, were established on a low-P soil in 2013 and high-P soils in 2013 and 2014, totaling 66 plots in all. Together with crop yield data, 65 tissue samples were collected from tomato farms. We found no significant yield response to P fertilization, despite large differences in soil-test P (coefficient of variation, 24%). High- and low-yield classes (cutoff: 91 Mg fruits ha−1) were classified by balance models with 78–81% accuracy using logit and Cate–Nelson partitioning models. The critical Mahalanobis distance for the partition was 5.31. Tomato yields were apparently not limited by P but were limited by calcium. There was no evidence that P fertilization should differ between center-pivot-irrigated and rain-fed crops. Use of the P budget method to arrive at the P requirement for tomato crops proved to be fallacious, as several nutrients should be rebalanced in Brazilian tomato cropping systems.

Sexual Differentiation and size at First Maturity of the MusselChoromytilus chorus(Molina, 1782) (Mollusca, Bivalvia) in Northern Chile.

The mussel Choromytilus chorus (Molina, 1782) is a commercially and ecologically important bivalve, which is extensively distributed along the Chilean coast (20°S–54°S). However, there are no previous studies regarding the reproductive aspects of this species in the northern part of its range. Mussels were collected at Caleta Errázuriz, along the Antofagasta coast (ca. 24°S), between December 2014 and June 2015. A total of 1620 individuals were examined using histological techniques and macroscopic visual inspection. Seventeen size categories, which included individuals from 5 mm to 100 mm in length, were analyzed. The size at the onset of sexual differentiation and the size at first sexual maturity (50% mature individuals) were determined. Males comprised 49% of the total sample, and 51% were females. Mussels from 5–22 mm in valve length were undifferentiated and from 22–24 mm were sexually differentiated. The size at first sexual maturity was recorded as 38–40 mm. In vitro fertilization trials demonstrated that sexually differentiated individuals were able to produce viable gametes. The biological parameters analyzed for C. chorus were similar to those recorded for populations of this bivalve from the southern latitudes. However, the lower number of eggs per female and the smaller egg size suggests that the population parameters may be different for C. chorus between the northern and southern latitudes.

Spermatological Parameters of Extended Rabbit Semen in 5% Indigenous Poultry Egg Yolk Plasma-Biofortified Extender

The in vitro evaluation of spermatological parameters is of great importance in the validation of semen samples to be used in artificial insemination. This study was aimed at evaluating the effect of 5% egg yolk plasma from 5 Nigerian domesticated avian species as a component of semen extender in the preservation of rabbit semen to be used for field fertility trials. The evaluated parameters (%) pre and post chilling storage were mass motility, forward progressive motility (FPM), liveability, acrosome integrity and total abnormalities at 37 0C, 0 hours, 5 0C, 24 hours and 5 0C, 48 hours. The 5% egg yolk plasma (EYP) was locally sourced from Chicken, Guinea fowl, Quail, Turkey and Muscovy bio assayed egg yolk samples. Semen samples used were aliquoted from the heterospermic pool of 20 bucks maintained under the same husbandry management regime. The result showed that at 37 °C post extension but pre-chilling storage, mass motility (%) in guinea fowl egg yolk plasma (GEYP) extended rabbit semen was significantly different (P<0.05) from that of the other samples compared except for Muscovy. The best acrosome integrity was recorded in Turkey (EYP) extended rabbit semen 76.00% while the best abnormality of 9.67 % was recorded with quail (EYP). After chilling for 24 hours at 5 0C, the best combination of spermatological parameters was found in quail egg yolk plasma (QEYP) containing extender having average mass motility of 63.00 %, FPM of 50.33 %, liveability of 82.33 %, acrosome integrity of 66.00 % and total abnormality of 6.67 % being the least. At 48 hours, QEYP extended semen gave the best result with the highest values of 74.67 %, 62.33 %, 81.67 % and 78.00 % for mass motility, FPM, liveability and acrosome integrity respectively. Quail (EYP) could be used as an alternative to chicken (EYP) in the production of semen extender for rabbit semen chilling storage. Key words : rabbit semen, egg yolk plasma, chilling storage, avian species.

Developing and testing an algorithm for site-specific N fertilization of winter oilseed rape

Winter oilseed rape (WOSR) is a major crop in Germany, combining economic benefits with a high value in crop rotation, but it still lacks agronomically sound concepts for site-specific nitrogen (N) fertilization. Since ecological challenges resulting from high optimal N rates and a low N harvest index are approaching on WOSR cropping systems, optimizing N fertilization becomes crucial. Recent studies showed the importance of taking autumnal N uptake into account when estimating optimal N rates for WOSR, thus autumnal N is pivotal in the algorithm that is introduced in this study. The algorithm was parameterized by using data from site-specific N fertilization trials and optimized to reduce N fertilizer amounts. Afterwards it was tested on different commercial farms in northern Germany. The autumnal N uptake was estimated using hyperspectral reflection measurements gained from tractor-mounted devices, and the data was processed to N application maps used for the N application in spring. In addition, a uniform optimal fertilization and a uniform application of average N rates calculated by the algorithm were applied to provide control treatments. Yield, N balance and economic net-revenue were evaluated for each treatment. Yields from site-specific fertilization were slightly lower (0.06t/ha) than from uniform optimal treatment but 0.22t/ha higher than from the uniform application of the site-specific N amount (not significant in both cases). The N balance was significantly lower when fertilizing site-specifically instead of applying uniform optimal N rate, while the net-revenues were slightly higher.

Pig sperm preincubation and gamete coincubation with glutamate enhance sperm-oocyte binding and in vitro fertilization

As the taste receptor for monosodium glutamate (umami) is expressed in both murine and human spermatozoa and the presence of α-gustducin and α-transducin, G proteins involved in the umami taste signaling, has been described in boar germ cells, the aim of this study was to evaluate if monosodium glutamate (MSG) would exert any effect on sperm-oocyte binding, in vitro fertilization (IVF) and sperm parameters during in vitro induced capacitation.For sperm-zona pellucida binding assay, boar spermatozoa were preincubated for 1 h and then coincubated for 1 h with denuded in vitro matured oocytes in presence of different concentrations of MSG (0, 0.1, 1, 10 mM). MSG 1 and 10 mM significantly (P < 0.05) increased the mean number of sperm bound to ZP compared with control (12.3 ± 9.0, 17.8 ± 11.3, 17.6 ± 10.8, MSG 0, 1 and 10 mM respectively).For in vitro fertilization trials, both sperm preicubation (1 h) and gamete coincubation (1 h) were performed in presence of different concentrations of MSG (0, 0.1, 1, 10 mM). After 19 h of culture in fresh IVF medium, oocytes were fixed. MSG 1 mM significantly (P < 0.05) increased the penetration rate compared with control (53.7 ± 20.4 vs. 36.8 ± 16.2).The addition of MSG during in vitro induced capacitation of boar spermatozoa did not cause any significant difference, compared with control, on the percentage of viable cells, spermatozoa with intact acrosome and the percentage of spermatozoa displaying tyrosine-phosphorylation of sperm tail proteins.In order to evaluate whether the effect elicited by MSG could be due to glutamate uptake in boar spermatozoa, fertilization trials were performed in presence of either 1 mM MSG or 1 mM MSG + 100 μM DL-threo-beta-hydroxyaspartic acid (THA), a non selective inhibitor of glutamate uptake. A significant increase (P < 0.05) in the penetration rate in both MSG and MSG + THA groups compared to control was recorded (39.8 ± 15.7, 53.7 ± 22.1, 52.2 ± 23.7, Control, MSG and MSG + THA respectively) while no difference in penetration rate between MSG and MSG + THA treatment was observed suggesting that sperm glutamate transporters are not involved in the pathway mediating this effect.Our study demonstrates for the first time that glutamate exerts a positive effect on sperm-oocyte binding and fertilization. Further studies are needed to clarify the mechanism by which glutamate exert his effect.

Consequences of uncontrolled cooling during sterlet (Acipenser ruthenus) sperm cryopreservation on post-thaw motility and fertilizing ability

The significant influence of the number and position of fish sperm sample straws in uncontrolled cooling devices on post-thaw spermatozoa parameters, such as motility and fertilizing ability, is presented in this study. The two most popular uncontrolled cooling devices were used in this study: a Styrofoam box setup with a polystyrene floating raft on liquid nitrogen and the dry shipper setup with a straw holder. We tested the effect of different quantities of straws (6 or 60) placed on the polystyrene floating raft and the position of the straws in the holder (on the periphery or in the centre). Using these cooling methods, sperm of 10 male sterlets diluted with methanol containing cryoprotective medium was frozen. All temperature changes were recorded by a thermocouple inside the straw, and the thermogram intervals were analysed. Spermatozoa motility was evaluated by video microscopy with integrated computer-assisted sperm analysis software. Fertilization trials were conducted at a 105 spermatozoa/egg ratio. Post-thaw spermatozoa parameters, including the percent of motile spermatozoa, curvilinear velocity, velocity according to the smoothed path, linearity of track, beat-cross frequency and fertilization rate, were significantly decreased in the 60-straw floating raft setup in comparison to all of the other cooling methods. The freezing rate between −10 °C and −30 °C was significantly decreased by up to 18.6 ± 0.61 °C/min for the 60-straw floating raft setup in comparison to the other freezing conditions. Considering the above results, efforts to standardize cryopreservation protocols using uncontrolled cooling devices should take into account the amount of straws subjected to freezing.

Biomass and nutrient allocation to aboveground components in fertilized Eucalyptus saligna and E. urograndis plantations

The objective of this study was to evaluate biomass allocation and nutrient pools in aboveground biomass components in 18-month-old plantations of Eucalyptus saligna and E. urophylla × E. grandis (i.e. E. urograndis) in Brazil. The plantations were established by pulp companies in a large area comprising three soil types (Acrisols, Vertisols and Leptosols) in the grassland biome in southern Brazil, and an operational regime of planting and maintenance fertilization was used to ensure full availability of nutrients. Vertisols showed the highest availability of soil nutrients, and the P and Ca concentrations in aboveground biomass were also highest in this type of soil. The nutritional status of both species indicates great consumption of nutrients, particularly of P, K and Ca. At this early age, canopy biomass components still made the largest relative contribution, although debarked stem biomass already accounted for 41.5% and 37.4 of total aboveground biomass in E. saligna, and E. urograndis, respectively. Nutrient concentrations in biomass components were similar across species. For all macronutrients, except Ca and Mg, the concentration gradient followed the order wood branches > wood > bark. The branches hold the majority of Ca reserves in biomass and are a very important pool of Mg, K, P and B. The bark makes a small contribution to total biomass, but stores a similar amount of Ca as leaves, being the second major pool after the branches. Comparison of the nutrients supplied by fertilization and the amounts stored in soil and aboveground indicates that the operational dose should be adjusted to each type of soil after further experimental fertilizer trials, as the supply of N and P appears to be too high, particularly for Vertisols. This is leading to the immobilization of P in biomass components that are not of importance in the biological or biochemical nutrient cycles, thus increasing the risk of larger exports of P during biomass removal.

Pentoxifylline effects on capacitation and fertility of stallion epididymal sperm

The aims of this study were to determinate whether pentoxifylline (PTX) increases the motion parameters of fresh and frozen-thawed equine epididymal spermatozoa, to evaluate the tyrosine phosphorylation of frozen-thawed epididymal sperm in the presence of PTX and to determine whether the PTX-treatment of stallion epididymal sperm prior to freezing improves the fertility response of mares to a reduced number of spermatozoa per insemination dose. Fifty epididymis were flushed with a skim milk based extender with or without PTX. The pre-treatment with PTX enhanced the sperm motility after being harvested (P<0.05); however the freeze-thaw process did not alter the sperm kinematics between control and treated samples (P>0.05). Plasma membrane integrity did not differ between control and PTX group after recovery and after thawing (P>0.05), as observed in tyrosine phosphorylation, which the PTX treatment did not alter the percentage of tail-associated immunofluorescence of cryopreserved epididymal sperm (P>0.05). For the fertility trial, different insemination groups were tested: 800×106 epididymal sperm (C800); 100×106 epididymal sperm (C100); 100×106 epididymal sperm recovered in an extender containing PTX (PTX100). The conception rates for C800; C100 and PTX100 were 68.7% (11/16); 31.5% (5/16) and 50% (8/16), respectively. The conception rate did not differ among groups (P>0.05), however, a low number of animals was used in this study. A trend toward significance (P=0.07) was observed between C800 and C100 groups. In conclusion, PTX has no deleterious effect on sperm motility, viability and capacitation of cryopreserved stallion epididymal sperm. The conventional artificial insemination with 100×106 sperm recovered with PTX ensures acceptable conception rates and maximize the limited number of doses of cryopreserved stallion epididymal sperm.

Sexual selection for genetic compatibility: the role of the major histocompatibility complex on cryptic female choice in Chinook salmon (Oncorhynchus tshawytscha).

Cryptic female choice (CFC), a form of sexual selection during or post mating, describes processes of differential sperm utilization by females to bias fertilization outcomes towards certain males. In Chinook salmon (Oncorhynchus tshawytscha) the ovarian fluid surrounding the ova of a given female differently enhances the sperm velocity of males. Sperm velocity is a key ejaculate trait that determines fertilization success in externally fertilizing fishes, thus the differential effect on sperm velocity might bias male fertilization outcomes and represent a mechanism of CFC. Once sperm reach the oocyte, CFC could potentially be further facilitated by sperm-egg interactions, which are well understood in externally fertilizing marine invertebrates. Here, we explored the potential genetic basis of both possible mechanisms of CFC by examining whether the genotypic combinations of mates (amino-acid divergence, number of shared alleles) at the major histocompatibility complex (MHC) class I and II explain the variation in sperm velocity and/or male fertilization success that is not explained by sperm velocity, which might indicate MHC-based sperm-egg interactions. We recorded sperm velocity in ovarian fluid, employed paired-male fertilization trials and evaluated the fertilization success of each male using microsatellite-based paternity assignment. We showed that relative sperm velocity was positively correlated with fertilization success, confirming that the differential effect on sperm velocity may be a mechanism of CFC in Chinook salmon. The variation in sperm velocity was independent of MHC class I and II. However, the MHC class II divergence of mates explained fertilization success, indicating that this locus might influence sperm-egg interactions.

Liming and application of nitrogen, phosphorus, potassium,and boron on a young plantation of chestnut

European chestnut is the most important cash crop in the highlands of NE Portugal. However, limited data on cropping technique are available to help farmers make decisions. This work is motivated by the lack of data related to chestnut response to fertilizer application. It reports results from a field fertilization trial consisting of the application of a combination of lime (L), nitrogen (N), phosphorus (P), potassium (K), and boron (B), namely LNPKB, NPKB, -NPKB, N-PKB, NP-KB, and NPK-B. Seedlings of chestnut were planted in June 2013 and grown for four growing seasons. Plant height, trunk diameter, and pruning wood were assessed every year and used as indicators of tree crop growth. Elemental leaf analysis and other tools [SPAD-502 chlorophyll meter; Field Scout CM 1000 NDVI (normalized difference vegetation index) meter, and the OS-30p+ fluorometer] were used to assess plant nutritional stresses. In January 2017 soil samples were collected at three depths (0-5, 5-10, and 10-20 cm) to determine several soil fertility parameters. The nonapplication of K and B reduced the tree crop growth and pruning residues. Leaf analysis revealed leaf K and B concentrations respectively in the NP?KB and NPK?B treatments to be in the deficient range previously established for chestnut. SPAD readings and NDVI detected the reduced availability of N associated with the -NPKB treatment but not the reduced plant growth associated with NP-KB or NPK-B treatments. The dark adaptation protocols of FV/FM, FV/F0, and OJIP measurements performed with the OS-30p+ fluorometer failed to diagnose the nutrient stresses detected by leaf analysis or the reduction in plant growth.

Grand Fir Nutrient Management in the Inland Northwestern USA

Grand fir (Abies grandis (Douglas ex D. Don) Lindley) is widely distributed in the moist forests of the Inland Northwest. It has high potential productivity, its growth being nearly equal to western white pine, the most productive species in the region. There are large standing volumes of grand fir in the region. Nutritionally, the species has higher foliage cation concentrations than associated conifers, especially potassium (K) and calcium (Ca). In contrast, it has lower nitrogen (N) foliage concentrations, which creates favorable nutrient balance on N-limited sites. Despite concentration differences, grand fir stores proportionally more nutrients per tree than associated species because of greater crown biomass. Although few fertilization trials have examined grand fir specifically, its response is inferred from its occurrence in many monitored mixed conifer stands. Fertilization trials including grand fir either as a major or minor component show that it has a strong diameter and height growth response ranging from 15% to 50% depending in part on site moisture availability and soil geology. Grand fir tends to have a longer response duration than other inland conifers. When executed concurrently with thinning, fertilization often increases the total response. Late rotation application of N provides solid investment returns in carefully selected stands. Although there are still challenges with the post-fertilization effects on tree mortality, grand fir will continue to be an important species with good economic values and beneficial responses to fertilization and nutrient management.

Effect of sperm preparation on development of bovine blastocyst in vitro.

Sperm preparation is an important step in the in vitro production of embryos. Centrifugation through colloids has been used to select normal sperm for assisted reproduction in several species. Animal models can sometimes be used as a preliminary step to investigate sperm preparation methods that are potentially of use for human fertility treatments. In this study bovine semen was prepared using three variants of the single-layer centrifugation sperm selection technique (Small, Mini, Mini-EP) with Bovicoll (Androcoll-B). Computer-assisted sperm motility analysis, the hypo-osmotic swelling test, and the sperm chromatin structure assay were performed on unselected (control) and SLC-selected sperm samples. Mini and Mini-EP gave the highest yield of motile spermatozoa, progressive motility and membrane integrity. In vitro fertilization trials were performed to investigate the fertilizing ability of the frozen-thawed bovine spermatozoa selected with Bovicoll. Mini-SLC (single-layer centrifugation) and swim-up (Control) were performed and cleavage rate and blastocyst rate did not differ significantly between groups. As there was a trend to an increased number of cells in blastocysts in the SLC group, the Mini-SLC method is at least as good as swim-up for selecting frozen-thawed bull spermatozoa for in vitro fertilization (IVF). This method could potentially be used to prepare human sperm for assisted reproduction.

An assessment of the effect of contact time on cadmium phytoavailability in a pasture soil.

The length of time cadmium (Cd) is in contact with the soil has been recognised as a factor affecting phytoavailability, but the extent of this process is currently poorly understood. This study used isotopic dilution techniques (E and L values) to determine the effect of contact time on Cd phytoavailability from soil collected from a long-term phosphorus (P) fertiliser trial. Cadmium phytoavailability was determined in soil that was last fertilised with soluble Cd from P fertiliser 17years prior to sampling (residual plots) and soil that received annual applications of P fertiliser until sampling (continuous plots). It was found that both E values and L values increased with P fertiliser (viz Cd) inputs and were significantly related to each other (r 2=0.82 P<0.005). There was however no significant difference (P<0.05) in the percentage of total Cd that was phytoavailable calculated using E values (E%) between the continuous (mean 51%) and the residual plots (mean 51%). There was also no significant difference (P<0.05) in the percentage of total soil Cd that was phytoavailable calculated using L values (L%) between the continuous (mean 77%) and residual plots (mean 87%). These results suggest that despite Cd being in contact with the soil for 17years, there was no difference in the size of the phytoavailable Cd pool compared to recent Cd inputs. This study should be repeated for other soil types and factored into any analysis for the long-term implications of ongoing Cd accumulation in soil on future landuse.

Molecular expression of caprine estrogen receptor gene 1 in reproductive and non-reproductive tissues.

During the last decades, physiological effects of oestrogens have been increasingly explored by scientists and biotechnologists. Estrogens exert a wide range of effects on a large variety of cell types. Oestrogen and its receptors are essential for sexual development and reproduction. Estrogen receptor alpha is a nuclear receptor activated by the hormone oestrogen. In male, ERα is encoded by the gene estrogen receptor gene 1 (ESR1), responsible for better fertility. The ESR1 is involved in the reabsorption of luminal fluid during the transit of spermatozoa from the testis to the head of the epididymis which is important for their survival and maturation during epididymal storage. The absence of ESR1 leads to reduced epididymal sperm content, reduced sperm motility and fertilizing ability. Therefore, this is a good startby to study the expression pattern of estrogen receptor 1 gene in high-fertile (G1) and low-fertile (G2) bucks of Jamunapari and Barbari breeds identified on the basis of seminal quality traits and fertility trials. RNA was extracted from the tissues by TRIzol method. The identification and expression pattern of caprine ESR1 gene was analysed by real-time PCR (Roche LC-480). Our work shows that the relative quantification by RT-PCR indicates more fold in head of epididymis as compared to spleen of caprine ESR1 gene. Furthermore, the RT-PCR indicated that fertile bucks of Jamunapari breed have more fold value as compared to Barbari breed in respect of reproductive organ.