Preovulatory serum estradiol concentration is positively associated with oocyte ATP and follicular fluid metabolite abundance in lactating beef cattle

Cattle induced to ovulate a small, physiologically immature preovulatory follicle had reduced oocyte developmental competence that resulted in decreased embryo cleavage and day 7 embryo quality compared with animals induced to ovulate a more advanced follicle. RNA-sequencing was performed on oocytes and their corresponding cumulus cells approximately 23 h after gonadotropin-releasing hormone (GnRH) administration to induce the preovulatory gonadotropin surge suggested reduced capacity for glucose metabolism and oxidative phosphorylation in the cumulus cells and oocytes from follicles ≤11.7 mm, respectively. We hypothesized that induced ovulation of a small, physiologically immature preovulatory follicle results in a suboptimal follicular microenvironment and reduced oocyte metabolic capacity. We performed a study with the objective to determine the impact of preovulatory follicle diameter and serum estradiol concentration at GnRH administration on oocyte metabolic competence and follicular fluid metabolome profiles. We synchronized the development of a preovulatory follicle and collected the follicle contents via transvaginal aspiration approximately 19 h after GnRH administration in lactating beef cows (n = 319). We determined ATP levels and mitochondrial DNA (mtDNA) copy number in 110 oocytes and performed ultra-high-performance liquid chromatography–high resolution mass spectrometry metabolomic studies on 45 follicular fluid samples. Intraoocyte ATP and the amount of ATP produced per mtDNA copy number were associated with serum estradiol concentration at GnRH and time from GnRH administration to follicle aspiration (P < 0.05). mtDNA copy number was not related to follicle diameter at GnRH, serum estradiol concentration at GnRH, or any potential covariates (P > 0.10). We detected 90 metabolites in the aspirated follicular fluid. We identified 22 metabolites associated with serum estradiol concentration at GnRH and 63 metabolites associated with follicular fluid progesterone concentration at the time of follicle aspiration (FDR < 0.10). Pathway enrichment analysis of significant metabolites suggested altered proteinogenesis, citric acid cycle, and pyrimidine metabolism in follicles of reduced estrogenic capacity pre-gonadotropin surge or reduced progesterone production by the time of follicle aspiration.     

Fisheries and conservation assessment of sharks in Pacific Panama

1. In Panama, shark fisheries were initially developed in the 1980s and progressively increased in production in the 1990s mainly due to the high demand for shark fins and meat from the international Asian market. Since then, and despite the exploitation rate (average 3,514 t year^–1) and endangered status of some species, shark fisheries have seldom been studied, and official statistics are general or incomplete and not suitable for the development of appropriate conservation and management strategies.
2. To understand the dynamics of shark fisheries in Panama, field surveys were conducted between 2007 and 2009 at several landing ports of small‐scale and industrial fisheries, at fish processing plants and on‐board fishing vessels in Pacific Panama, where most of the fishing vessels of the country operate.
3. In general, it was found that the artisanal and industrial fisheries of the Pacific coast of Panama regularly exploit at least 18 species of sharks, which are also being exploited by neighbouring countries in the eastern Pacific, suggesting the importance of coordinated conservation initiatives across the multiple jurisdictions. A large number of the individuals caught were immature, implying a certain level of impact on recruitment rates. This pattern was particularly evident in species such as Sphyrna lewini, for which immature individuals represented at least 99% and 63% of the total catch by small‐scale and industrial fisheries, respectively. Catch per unit of effort analyses showed that Carcharhinus and Sphyrna species were the most exploited (representing ~80% of the catches) by industrial fisheries in Panama between 2006 and 2009, suggesting that fishery management should provide special attention to these groups.
4. It is expected that the information presented here provides a baseline to develop new regulations, including the implementation of annual quotas and fishing seasons and the protection of nursery areas, for the long‐term sustainability and conservation of sharks in Panama.

     

Hematologic and serum biochemical reference values for the wild Spectacled Caiman, Caiman crocodilus crocodilus, from the Venezuelan plains

Background: Commercial farming of Caiman crocodilus crocodilus has had an impact on the use of this species for meat consumption and the leather industry. Spectacled Caimans comprise part of the South American plains biodiversity. Misinterpretation of laboratory data is a risk owing to the limited hematologic and serum biochemical values available for this species. Objective: The aim of this study was to determine hematologic and serum biochemical values for wild Spectacled Caimans from the Venezuelan plains. Methods: Blood samples were collected form the caudal tail vein of 100 Spectacled Caimans (40 males and 60 females) from the plains located in the State of Apure. Values for RBC count, PCV, hemoglobin concentration, WBC absolute and differential counts, and thrombocyte counts were obtained using manual methods, and RBC indices were calculated. Serum biochemical analysis included measurement of alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, and creatine kinase activities and concentrations of total protein and albumin. Comparisons between sexes were analyzed using the Mann–Whitney test. Results: Reference values for wild Spectacled Caimans were determined. Minor differences in hematologic values, particularly for RBC counts, were found compared with previously published values for this species. Serum biochemical values were similar to those available for other crocodilians. There were no significant differences between males and females. Conclusions: Minor differences between the values obtained for wild Spectacled Caimans and those previously published for this species may be related to differences in methodology and environmental conditions. Availability of hematologic and serum biochemical reference values will be useful for accurate diagnosis and management of disease in this species.     

The influence of CCL3L1 gene-containing segmental duplications on HIV-1/AIDS susceptibility

Segmental duplications in the human genome are selectively enriched for genes involved in immunity, although the phenotypic consequences for host defense are unknown. We show that there are significant interindividual and interpopulation differences in the copy number of a segmental duplication encompassing the gene encoding CCL3L1 (MIP-1alphaP), a potent human immunodeficiency virus-1 (HIV-1)-suppressive chemokine and ligand for the HIV coreceptor CCR5. Possession of a CCL3L1 copy number lower than the population average is associated with markedly enhanced HIV/acquired immunodeficiency syndrome (AIDS) susceptibility. This susceptibility is even greater in individuals who also possess disease-accelerating CCR5 genotypes. This relationship between CCL3L1 dose and altered HIV/AIDS susceptibility points to a central role for CCL3L1 in HIV/AIDS pathogenesis and indicates that differences in the dose of immune response genes may constitute a genetic basis for variable responses to infectious diseases.     

The length‐times‐width proxy for leaf area of eelgrass:criteria for evaluating the representativeness of leaf‐width measurements

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Environmental and economic impacts of reducing total phosphorous runoff in an agricultural watershed

The economy of northwest Arkansas relies greatly upon livestock and poultry production. The supply of production by-products is increasingly coming under scrutiny as an important source of water pollution in the region. This study uses stochastic dominance techniques to evaluate, environmentally and economically, a range of ten best management practice scenarios to lessen water pollution in the Lincoln Lake watershed. The goal is to generate rankings that could be useful for supporting producers’ and watershed managers’ selection of management practices to reduce total phosphorous losses in runoff. Specifically, this study compares scenarios in terms of net return risk reduction for bermudagrass hay producers.The results showed that environmental and economic rankings differ from each other. Although all scenarios analyzed were effective in reducing total phosphorous losses when compared to a baseline, six of them also decreased net returns. This suggests that including some best management practices may lead to increased net return risk. However, some scenarios were identified that may increase net returns, reduce total phosphorous losses and do not differ considerably from producers’ current management practices.The previous results suggested that the joint environmental-economic impact was important when considering scenarios and that producers’ risk attitudes and best management practices’ economic impacts should be accounted for when selecting scenarios. Producers and watershed managers can weigh trade-offs between total phosphorous losses reduction and net returns variability when making water conservation decisions.     

Automation of border irrigation in South-East Australia: an overview

There exists a growing interest in automating border irrigation after a large number of irrigated farms in South East Australia have upgraded their layout design. Several manufacturing companies are producing automated equipment which rely on controllers fitted with timers or field water sensors to monitor the advance of the water front down the border (bay). Labor saving together with potential for increase in pasture yield and additional flexibility to perform other farming tasks are the main benefits considered by farmers who decide to adopt automation. Environmental benefits can also be realized provided that the system is properly managed. Correct sensor placement and timer setting are critical factors to achieve high hydraulic performance as they can influence the application efficiency of a typical border irrigation event by as much as 40%. Further efforts will be required in future to incorporate feedback control, improve operational reliability and adapt existing systems or develop new ones to meet the requirements of new irrigation techniques such as surge flow.     

Analysis of Manual and Centralised Supervisory Control Operations to Improve Level of Service: A Case Study of Pyramid Hill No 1 Channel, Victoria, Australia

The current challenge facing irrigation inAustralia is tofind ways to improve the operationalperformance of existing systems rather thanconstructing new ones. Unsteady flowsimulation models are often used as keytools to study and test improvedoperational scenarios for existing systems.While these models are generally notrecommended for real-time control, researchhas shown that they are able to simulatecanal response for different test scenariosfor operations planning. This paperpresents the results of two alternativemodes of operation for the Pyramid Hill No.1 Channel in northern Victoria, Australia.The channel is currently under manualoperation. Centralised control is the mostimmediate option considered by theirrigation authority to enable remotesupervision and control of the canal toimprove the channel operation and level ofservice standards. This type of control istermed Supervisory Control and DataAcquisition (SCADA). The two alternativeoperational scenarios were simulated andanalysed using the unsteady flow-simulationmodel DUFLOW. Specific performanceindicators were defined to compare the twomodes of operations based on the simulationresults. The results show that SCADAoperation has considerable potential toclosely match the discharges at thedownstream regulator with those ordered byfarmers while maintaining the water surfaceelevations within allowable fluctuationtolerance throughout the length of thecanal.