CASA Assessment of Kinematic Parameters of Ram Spermatozoa and their Relationship to Migration Efficiency in Ruminant Cervical Mucus

Sperm motility is an indicator of male fertility because of its importance for sperm migration through the female genital tract and for gamete interaction at fertilization. This study analyses the relationship between computer assisted semen analysis (CASA) motility patterns and sperm migration of rams in ruminant cervical mucus. In experiment 1, spermatozoa extended with sperm analysis medium (SAM) and seminal plasma were compared in terms of motility. In experiment 2, 56 semen samples were collected either with artificial vagina (AV) or electroejaculator to be compared in terms of motility performance. In experiment 3, 104 ejaculates collected by AV from 26 males were analysed via the CASA system to characterize their motility patterns. In experiment 4, ejaculates from pairs of rams (20 rams in total) were simultaneously assessed for mucus migration (ovine, caprine, bovine) and motility patterns to evaluate the correlations between both parameters. Semen collected by AV and extended in SAM allows the most reliable assessment for sperm motility. Ram spermatozoa move fast and follow a linear trajectory compared with other ruminants. Continuous line velocity (VCL) and average path velocity (VAP) are the only sperm kinematic parameters that presented significant positive correlations with the ability to migrate in sheep cervical mucus (p < 0.05). Continuous line velocity, VAP, straight line velocity and linearity are highly significantly related with migration efficiency in goat cervical mucus (p < 0.01) and only lateral head displacement is negatively related to sperm migration in bovine cervical mucus (p < 0.05). These results suggest that specific kinematic parameters confer the ability of spermatozoa to colonize and migrate through epithelial mucus with different rheological properties.     

Bioenergetic evaluation of diel vertical migration by bull trout (Salvelinus confluentus) in a thermally stratified reservoir

Many species living in deeper lentic ecosystems exhibit daily movements that cycle through the water column, generally referred to as diel vertical migration (DVM). In this study, we applied bioenergetics modelling to evaluate growth as a hypothesis to explain DVM by bull trout (Salvelinus confluentus) in a thermally stratified reservoir (Ross Lake, WA, USA) during the peak of thermal stratification in July and August. Bioenergetics model parameters were derived from observed vertical distributions of temperature, prey and bull trout. Field sampling confirmed that bull trout prey almost exclusively on recently introduced redside shiner (Richardsonius balteatus). Model predictions revealed that deeper (>25 m) DVMs commonly exhibited by bull trout during peak thermal stratification cannot be explained by maximising growth. Survival, another common explanation for DVM, may have influenced bull trout depth use, but observations suggest there may be additional drivers of DVM. We propose these deeper summertime excursions may be partly explained by an alternative hypothesis: the importance of colder water for gametogenesis. In Ross Lake, reliance of bull trout on warm water prey (redside shiner) for consumption and growth poses a potential trade‐off with the need for colder water for gametogenesis.     

Assessment of the Bacteriocinogenic Potential of Marine Bacteria Reveals Lichenicidin Production by Seaweed-Derived Bacillus spp.

The objectives of this study were (1) to assess the bacteriocinogenic potential of bacteria derived mainly from seaweed, but also sand and seawater, (2) to identify at least some of the bacteriocins produced, if any and (3) to determine if they are unique to the marine environment and/or novel. Fifteen Bacillus licheniformis or pumilus isolates with antimicrobial activity against at least one of the indicator bacteria used were recovered. Some, at least, of the antimicrobials produced were bacteriocins, as they were proteinaceous and the producers displayed immunity. Screening with PCR primers for known Bacillus bacteriocins revealed that three seaweed-derived Bacillus licheniformis harbored the bli04127 gene which encodes one of the peptides of the two-peptide lantibiotic lichenicidin. Production of both lichenicidin peptides was then confirmed by mass spectrometry. This is the first definitive proof of bacteriocin production by seaweed-derived bacteria. The authors acknowledge that the bacteriocin produced has previously been discovered and is not unique to the marine environment. However, the other marine isolates likely produce novel bacteriocins, as none harboured genes for known Bacillus bacteriocins.     

Effect of Cereal Rye and Hairy Vetch on Pest Suppression and Corn Yield

A study was conducted in 2016 to determine the effect of cereal rye (Secale cereale) and hairy vetch (Vicia villosa) combination on pest suppression and corn yield in Northwest Missouri. The experiments consisted of six treatments corresponding to cereal rye and hairy vetch combinations, plus a control. The corn treatments included conventional corn and transgenic corn. Harvested ears were assessed for rating on corn earworm damage and fungal damage on ears. Similarly, corn yield was measured across the treatments on randomly selected ears. Visual assessments of weed suppression, pest suppression (corn earworm damage), and fungal ear rots revealed no significant treatment effects. However, relevant trends in higher corn yield were observed with increasing hairy vetch proportion from 33% to 66% level. Delayed termination of hairy vetch caused poor corn growth and higher true armyworm (Mythimna unipuncta) infestation.     

Spatially resolved calcium dynamics of mammalian Purkinje cells in cerebellar slice

Microfluorometric imaging was used to study the correlation of intracellular calcium concentration with voltage-dependent electrical activity in guinea pig cerebellar Purkinje cells. The spatiotemporal dynamics of intracellular calcium concentration are demonstrated during spontaneous and evoked activity. The results are in agreement with hypotheses of dendritic segregation of calcium conductances suggested by electrophysiological experiments. These in vitro slice fluorescence imaging methods are applicable to a wide range of problems in central nervous system biochemical and electrophysiological functions.     

Serological Characterization of 8 Haemophilus Pleuropneumoniae Strains and Proposal of a New Serotype: Serotype 8

Eight strains of Haemophilus pleuropneumoniae isolated from 8 herd outbreaks of pleuropneumonia in pigs were studied by means of the slide agglutination test, the tube agglutination test, the IHA test and by gel diffusion.The 8 strains were antigenically homogeneous and serologically distinct from serotypes 1 through 7. It is therefore proposed to refer these strains to a new serotype: serotype 8, with strain 405 as the type strain.In addition to the serotype-specific capsular antigens, capsular antigen of serotype 3 (strain 1421) and serotype 6 (strain Femø) could be demonstrated in the 8 strains by means of the IHA test and by gel diffusion analyses.     

Lipid Composition of Hepatic and Adipose Tissues From Normal Cats and From Cats With Idiopathic Hepatic Lipidosis

The purpose of this study was to characterize the lipid classes in hepatic and adipose tissues from cats with idiopathic hepatic lipidosis (IHL). Concentrations of triglyceride, phospholipid phosphorus, and free and total cholesterol were determined in lipid extracts of liver homogenates from 5 cats with IHL and 5 healthy control cats. Total fatty acid composition of liver and adipose tissue was also compared. Triglyceride accounted for 34% of liver by weight in cats with IHL (338 ± 38 mg/g wet liver) versus 1% in control cats {9.9 ±1.0 mg/g wet liver, P < .001). The mass of cholesterol ester was significantly higher in triglyceride-free (TG-free) liver from cats with IHL (741 ± 340 μg/g TG-free wet liver) compared to healthy cats (31 ± 11 μg/g TG-free wet liver, P < .05). Total fatty acid composition of hepatic tissue in the 2 groups differed; pa Imitate was higher (19.5 ± 1.1% of total fatty acids in cats with IHL versus 9.2 ± 2.7% in controls, P < .05), stearate was lower (8.5 ± 0.8% versus 16.8 ± 1.1%, P < .05), oleate was higher (41.2 ± 1.6% versus 31.1 ± 1.8%, P < .05), and arachidonate was lower (1.2 ± 0.2% versus 6.0 ± 0.9%, P < .05). The total fatty acid composition of adipose tissue also differed between the 2 groups; palmitate was higher (25.2 ± 1.2% in cats with IHL versus 21.3 ± 0.6% in controls, P < .05), total monounsaturated fatty acids were higher (48.4 ± 1.0% versus 45.0 ± 0.8%, P < .05), linoleate was lower (13.3 ± 1.6% versus 17.5 ± 0.9%, P < .05), total (n-6) fatty acids were lower (13.8 ± 1.38% versus 18.4 ± 0.83%, P < .05), linolenate was lower (0.2 ± 0.04% versus 0.7 ± 0.06%, P < .05), and total (n-3) fatty acids were lower (0.3 ± 0.02% versus 1.3 ± 0.32%, P < .05). The fatty acid composition of both liver and adipose tissue was similar for stearate, oleate, linoleate, and linolenate in cats with IHL. These results support the hypothesis that the origin of hepatic triglyceride in cats with IHL is the mobilization of fatty acids from adipose tissue.