Standing Laparoscopic Peritoneal Flap Hernioplasty of the Vaginal Rings does not Modify the Sperm Production and Motility Characteristics in Intact Male Horses

Laparoscopic hernioplasty techniques have been developed in the recent years to avoid the recurrence of inguinal hernias and to spare the testicles for breeding purposes in stallions. However, there have been no previous comprehensive and systematic studies of the reproductive outcomes and prognoses for stallions after inguinal hernioplasty. Therefore, the objective of this study was to assess the possible effects of one of these techniques (standing laparoscopic peritoneal flap hernioplasty) on the sperm production and motility characteristics of six healthy stallions that received this procedure based on 1‐year follow‐ups. There were no significant differences in the measured sperm variables (assessments based on the DSO, MOT, PMOT, VSL, VCL and VAP) during 1‐year follow‐ups.     

Changes in Bull Sperm Kinematics after Single Layer Centrifugation

The objective of this study was to evaluate bull sperm kinematics after centrifugation through a single layer of a colloid [Single Layer Centrifugation (SLC)]. Ejaculates from 20 bulls were extended and stored at 4–6°C for 24 h during transport to the laboratory for SLC through Androcoll‐B, followed by measurement of sperm kinematics in all samples. Total motility (86% and 88% for uncentrifuged and SLC samples, respectively) and progressive motility (84% for both the groups) were similar (p > 0.05). In contrast, straightness (STR) (0.65 vs 0.69), linearity (LIN) (0.32 vs 0.35) and beat cross frequency (BCF) (22.3 vs 23.6 Hz) were significantly higher in the SLC‐selected samples than in the uncentrifuged samples, whereas velocity of the average path (VAP) (95 vs 90 μm/s), curvilinear velocity (VCL) (192 vs 180 μm/s), amplitude of lateral head deviation (ALH) (7 μm vs 6.5 μm) and hypermotility (49% vs 38%) were significantly decreased. The kinematics of the samples with the poorest motility was improved most by SLC. In conclusion, even though SLC had no direct effect on total and progressive motility, it appeared to have a positive influence on several other kinematic parameters that may be important for fertilization after artificial insemination.     

A metagenomic survey of microbes in honey bee colony collapse disorder

In colony collapse disorder (CCD), honey bee colonies inexplicably lose their workers. CCD has resulted in a loss of 50 to 90% of colonies in beekeeping operations across the United States. The observation that irradiated combs from affected colonies can be repopulated with naive bees suggests that infection may contribute to CCD. We used an unbiased metagenomic approach to survey microflora in CCD hives, normal hives, and imported royal jelly. Candidate pathogens were screened for significance of association with CCD by the examination of samples collected from several sites over a period of 3 years. One organism, Israeli acute paralysis virus of bees, was strongly correlated with CCD.     

Regulated protein denitrosylation by cytosolic and mitochondrial thioredoxins

Nitric oxide acts substantially in cellular signal transduction through stimulus-coupled S-nitrosylation of cysteine residues. The mechanisms that might subserve protein denitrosylation in cellular signaling remain uncharacterized. Our search for denitrosylase activities focused on caspase-3, an exemplar of stimulus-dependent denitrosylation, and identified thioredoxin and thioredoxin reductase in a biochemical screen. In resting human lymphocytes, thioredoxin-1 actively denitrosylated cytosolic caspase-3 and thereby maintained a low steady-state amount of S-nitrosylation. Upon stimulation of Fas, thioredoxin-2 mediated denitrosylation of mitochondria-associated caspase-3, a process required for caspase-3 activation, and promoted apoptosis. Inhibition of thioredoxin-thioredoxin reductases enabled identification of additional substrates subject to endogenous S-nitrosylation. Thus, specific enzymatic mechanisms may regulate basal and stimulus-induced denitrosylation in mammalian cells.     

Biomass energy from crop and forest residues

Residues remaining after the harvest of crop and forestry products are being proposed as a substantial energy source for the nation. An estimated 22 percent of the residues might be utilized, providing a renewable source of high-grade energy with the potential of supplying 1 percent of the current U.S. gasoline consumption as ethanol or 4 percent of the total electrical energy used. These net energy benefits are limited by high energy costs to collect, transport, and process the residues. Environmental threats include soil erosion, water runoff, and nutrient loss.     

A 48-million-year-old aphid--host plant association and complex life cycle: biogeographic evidence

Biogeographical and paleobotanical evidence suggests that the aphid subtribe Melaphidina has been associated with its sumac host plant since the early Eocene when these plants were continuously distributed across the Bering land bridge. Transfer experiments indicate that the American species, Melaphis rhois, shows an unusual complex life cycle, similar to that known in Chinese melaphidines, with some generations feeding on mosses as alternate host plants. As with the association with sumac, this complex life cycle may have been established in the melaphidine lineage before the southward retreat of sumac from Alaska 48 million years ago. This example suggests that the interactions and life histories shown by modern populations may be determined, in large part, by evolutionary commitments made in the distant past.     

Standardising multi-laboratory microsatellite data in Pacific salmon: an historical view of the future

Abstract –  For at least 15 years, multiple Pacific Rim Laboratories have cooperated to standardise the collection of Pacific salmon genetic data. For species such as Chinook salmon and chum salmon, allozyme electrophoretic data sets now include hundreds of populations sampled over multiple years throughout the north Pacific. More recently, microsatellite DNA markers have emerged as a new cornerstone of Pacific salmon genetic research. The allozyme experience provides at least two important lessons regarding shared, standardised databases. First, interlaboratory standardisation is sufficiently costly and time consuming that little progress is typically made in the absence of specific fishery management and conservation needs; thus immediate needs will direct future standardisation. Secondly, justified or not, there are significant concerns regarding intellectual propriety and other perceived privileges associated with unpublished genetic data that are shared among laboratories. This article describes challenges to genetic standardisation relative to new research goals, along with specific suggestions for meeting those challenges.     

Size heterogeneity, growth potential and aggression in juvenile yellowtail kingfish (Seriola lalandi Valenciennes)

The ontogenetic development of size heterogeneity and aggression was monitored in commercial culture tanks of yellowtail kingfish (Seriola lalandi Valenciennes). Size heterogeneity increased substantially with the introduction of Artemia as a food source at 12 days post‐hatch (DPH), and was correlated with the appearance of aiming behaviour, a precursor to more direct aggressive interactions. Chasing behaviour started at approximately 19 DPH (10–12 mm total length), with the main aggressors being large‐grade individuals comprising 8% of the population. At any one time, only 10–30% of this grade carried out all of the chases, meaning that a very small proportion of the entire population (1%) was responsible for most of the aggressive interactions. The main recipients of aggression were the small grade, comprising 42% of the population, while the medium grade (50% of the population) were generally not aggressive and received only a low to moderate level of aggression. A grading trial showed that large‐grade juveniles only displayed aggressive behaviour in the presence of size heterogeneity, and that medium‐ or small‐grade juveniles did not establish an agonistic hierarchy in the absence of large individuals. A high level of aggression in the ungraded control treatment was associated with mortality of most of the small individuals. Even in the absence of aggression, the small‐grade juveniles failed to gain weight or show an increase in the RNA/DNA ratio after 12 days. The large‐ and medium‐grade larvae showed an isometric increase in RNA/DNA ratio during development, indicating that faster‐growing individuals are likely the result of better food capture or processing traits rather than better protein synthesis rates. Decreasing size heterogeneity and aggression via grading mostly benefits the medium‐grade individuals, as the majority of small individuals within a batch appear to be on a degenerative developmental trajectory irrespective of an aggressive environment.     

Increased apoptosis of CD4 and CD8 T lymphocytes in the airways of horses with recurrent airway obstruction

Recurrent airway obstruction (RAO, also known as equine heaves) is an inflammatory condition similar to human asthma caused by exposure of susceptible horses to poorly ventilated stable environments. The disease is characterized by neutrophilic airway inflammation, mucus hypersecretion and reversible bronchoconstriction. This inflammatory process is mediated by several factors, including antibodies, cytokines, resident cells of the airway and inflammatory cellular components that arrive in the respiratory tract. An increasing body of evidence has lent support to the concept that a dysregulation of T cell apoptosis may play a central role in the development of airway inflammation and the associated asthma. Therefore, the aim of this study was to investigate early and late apoptosis of CD4 and CD8 T cell subpopulations obtained from the airways of acute RAO-positive animals after exposure to hay/straw. The percentages of CD4 and CD8 T cells and their associated frequencies of apoptosis were quantified using flow cytometry. Hay/straw exposure induced clinical airway obstruction, airway neutrophilia and increased airway mucus production in RAO-positive horses. In addition, allergen exposure increased the percentage of CD4 T cells in RAO-positive horses as well as the frequency of early and late apoptosis in both CD4 and CD8 lymphocyte subpopulations. These results suggest that the higher frequency of lymphocyte apoptosis may play a role in disease progression of horses afflicted with RAO and may partially explain the characteristic remission of this pathological condition once the allergen source is removed. However, further studies are needed to clarify the role of T cell apoptosis in RAO-affected horses.