Effects of shredding on silage density and fermentation quality

The effects of shredding forages on the density and fermentation quality of the resulting silages were studied. Lucerne (Medicago sativa L.), red clover (Trifolium pratense L.), perennial ryegrass (Lolium perenne L.) and a grass–clover mixture were harvested and wilted indoors for 1–2 days. The dry‐matter content of the forages after wilting was 192 g/kg, 192 g/kg, 237 g/kg and 214 g/kg respectively. The forages were then either unprocessed or shredded once (1×) or four (4×) times using a novel laboratory shredder and were ensiled in laboratory‐scale silos. Fermentation was terminated after either 50 or 113 days of ensiling. Density and the fermentation weight losses of the silages were recorded. Initial density of the silages was considerably increased with increased intensity of shredding (p < 0.01). The initial density (DM basis) of the 4× shredded silages ranged from 177 to 236 kg DM/m³ whereas it was 124–163 kg DM/m³ in non‐shredded silages. The 4× shredded silages had the greatest fermentation weight loss at day 1 of ensiling (p < 0.01). Overall fermentation weight loss after 113 days of ensiling was reduced in the 4× shredded silages (p < 0.01). Shredding increased L‐lactate concentration and reduced pH of the silages (p < 0.01). The NH₃ concentrations were reduced by 25%–46% in 4× shredded silages and butyrate concentrations were reduced by 76%–97% in shredded silages in comparison to non‐shredded silages (p < 0.01). Shredding improved initial density and fermentation quality of silages while reducing overall fermentation weight losses.     

Degradation products of polycondensed aromatic moieties (black carbon or pyrogenic carbon) in soil: Methodological improvements and comparison to contemporary black carbon concentrations

It was found that benzenepolycarboxylic acids (BPCA) do naturally occur in soils. They can be assumed as black carbon degradation products. We propose an improved method to analyse black carbon degradation products in soil. Method optimization comprised extraction duration, sample clean‐up, and chromatographic separation conditions. The method is also suitable for subsequent isotope ratio mass spectrometry of individual BPCA. Accuracy was checked with quartz sand and soil samples spiked with known amounts of BPCA. In soil samples with varying properties we compared contents of black carbon and black carbon degradation products, i.e., total and free BPCA contents, respectively. Results show that our proposed method can extract black carbon degradation products from soil after 48 h of extraction with 500 mM NaOH compared to 72 h of the original method. Polyvalent cations should be removed by Dowex 50 W X 8, 200–400 mesh, while original cation removal with Merck cation exchange resin was not successful. Free BPCA can be separated and quantified directly by ion exchange chromatography followed by ultraviolet spectroscopy or isotope ratio mass spectrometry, while the original method involved another two days for derivatization and isolation of derivatized BPCA. Recovery of spiked BPCA to a range of different soil samples was 81 ± 19%. Free BPCA concentrations of a Cambisol, Chernozem, Ferralsol, and Anthrosol varied between 0 and 0.24 g kg^?1 contributing 0–38% of total black carbon concentration. Free BPCA correlated with total black carbon, total organic carbon, and negatively with pH. However, further studies with a larger set of samples are necessary to systematically investigate conditions for black carbon degradation and, thus free BPCA formation in soils.     

Transobturator vaginal tape inside out for treatment of urethral sphincter mechanism incompetence in female dogs: cadaveric study and preliminary study in continent female dogs

Objectives: (1) To describe a surgical technique adapted from the “transobturator vaginal tape inside‐out” (TVT‐O) used in women and to define the trajectory of the tape on canine cadavers, and (2) to determine the urodynamic and morphological effects of the TVT‐O in continent bitches. Study Design: Cadaveric and experimental in vivo study. Animals: Fresh female canine cadavers (n=12) and spayed female Beagle dogs (2). Methods: (1) TVT‐O was inserted in 12 cadavers. Dissection was performed and distances between the tape and neighboring structures were recorded. (2) TVT‐O was inserted in 2 continent female Beagle dogs. Urethral pressure profilometry and vaginourethrograms were performed preoperatively, immediately after surgery, and 2, 4, and 6 months postoperatively. Histopathology was performed 6 months after surgery. Results: (1) TVT‐O tape was consistently located in a perineal space before entering the obturator foramina and was located at a safe distance from major neurovascular structures including the femoral vessels and obturator nerve. (2) TVT‐O was performed without any surgical or postoperative complications in 2 continent bitches. Histopathologic examination of the tissues surrounding the tape revealed a mild fibroblastic proliferation with a mild to minimal lymphoplasmacytic inflammatory infiltration. Conclusions: TVT‐O is a feasible and accurate procedure that can be performed in continent bitches with a low risk of complications.     

Ecometrics: The traits that bind the past and present together

We outline here an approach for understanding the biology of climate change, one that integrates data at multiple spatial and temporal scales. Taxon-free trait analysis, or “ecometrics,” is based on the idea that the distribution in a community of ecomorphological traits such as tooth structure, limb proportions, body mass, leaf shape, incubation temperature, claw shape, any aspect of anatomy or physiology can be measured across some subset of the organisms in a community. Regardless of temporal or spatial scale, traits are the means by which organisms interact with their environment, biotic and abiotic. Ecometrics measures these interactions by focusing on traits which are easily measurable, whose structure is closely related to their function, and whose function interacts directly with local environment. Ecometric trait distributions are thus a comparatively universal metric for exploring systems dynamics at all scales. The main challenge now is to move beyond investigating how future climate change will affect the distribution of organisms and how it will impact ecosystem services and to shift the perspective to ask how biotic systems interact with changing climate in general, and how climate change affects the interactions within and between the components of the whole biotic-physical system. We believe that it is possible to provide believable, quantitative answers to these questions. Because of this we have initiated an IUBS program iCCB (integrative Climate Change Biology).     

Molecular breeding for virus resistant potato plants

To engineer resistance against potato virus X (PVX), the viral coat protein (CP) gene has been introduced into two potato cultivars. Stable expression of the gene in transgenic clones throughout the growing season has been obtained and resulted in considerably increased virus resistance. With varying frequencies depending on the original cultivar used, true-to-type PVX resistant transgenic clones have been obtained. Since deviant light sprout characteristics were invariably associated with aberrations in plant phenotype, they can be used in procedures to early screen for deviations. Furthermore, it has been possible to unequivocally discriminate between the original untransformed and independent transgenic cultivars. Although no relation has been found between the presence, if any, of the CP of potato virus Y (PVY) or potato leafroll virus (PLRV) in CP gene transgenic potato, appreciable levels of resistance to these viruses has been obtained. This suggests that the mechanism by which a viral CP gene in the potato genome evokes resistance, differs amongst various viruses.     

Combining ability,heterosis and genetic diversity in tropical maize (<Emphasis Type="Italic">Zea mays</Emphasis> L.) under stress and non-stress conditions

Drought and low soil fertility are considered the most important abiotic stresses limiting maize production in sub-Saharan Africa. Knowledge of the combining ability and diversity of inbred lines with tolerance to the two stresses and for those used as testers would be beneficial in setting breeding strategies for stress and nonstress environments. We used 15 tropical maize inbred lines to (i) evaluate the combining ability for grain yield (GY), (ii) assess the genetic diversity of this set of inbred lines using RFLP, SSR, and AFLP markers, (iii) estimate heterosis and assess the relationship between F₁ hybrid performance, genetic diversity and heterosis, and (iv) assess genotype × environment interaction of inbred lines and their hybrids. The F₁ diallel hybrids and parental inbreds were evaluated under drought stress, low N stress, and well-watered conditions at six locations in three countries. General combining ability (GCA) effects were highly significant (P < 0.01) for GY across stresses and well-watered environments. Inbred lines CML258, CML339, CML341, and CML343 had the best GCA effects for GY across environments. Additive genetic effects were more important for GY under drought stress and well-watered conditions but not under low N stress, suggesting different gene action in control of GY. Clustering based on genetic distance (GD) calculated using combined marker data grouped lines according to pedigree. Positive correlation was found between midparent heterosis (MPH) and specific combining ability (SCA), GD and GY. Hybrid breeding program targeting stress environments would benefit from the accumulation of favorable alleles for drought tolerance in both parental lines.     

Comparison of the Recurrence Rate of Gastric Dilatation with or Without Volvulus in Dogs after Circumcostal Gastropexy Versus Gastrocolopexy

OBJECTIVE: To compare the recurrence rate of acute gastric dilatation with or without volvulus (GDV) after circumcostal gastropexy (CCGP) or gastrocolopexy (GCP) in dogs. STUDY DESIGN: A prospective, double-blind, multicenter, randomized, controlled, clinical trial with two groups (A and B). ANIMALS: Fifty-four client-owned dogs presented for treatment of GDV. METHODS: Dogs with acute GDV that had not previously had a gastropexy performed were included. The preoperative treatment before gastropexy was standardized. A CCGP was performed on dogs in group A, and a GCP was performed on dogs in group B. Postoperative treatment was standardized, but deviation did occur according to the special needs of particular patients. A minimal follow-up time of 180 days was required for dogs not excluded from the study. The median follow-up time in group A was 700 days; in group B, it was 400 days. The occurrence of abdominal pain and gastrointestinal problems after surgery were recorded by the owners. RESULTS: There was no significant difference in the recurrence rate of GDV between the two groups. At the end of the study, the recurrence rate was 9% and 20% in group A and in group B, respectively. CONCLUSIONS: Both surgical techniques are effective in preventing recurrence of GDV.     

A longitudinal study of Campylobacter distribution in a turkey production chain

Background

Campylobacter is the most common cause of bacterial enteritis worldwide. Handling and eating of contaminated poultry meat has considered as one of the risk factors for human campylobacteriosis.Campylobacter contamination can occur at all stages of a poultry production cycle. The objective of this study was to determine the occurrence of Campylobacter during a complete turkey production cycle which lasts for 1,5 years of time. For detection of Campylobacter, a conventional culture method was compared with a PCR method. Campylobacter isolates from different types of samples have been identified to the species level by a multiplex PCR assay.

Methods

Samples (N = 456) were regularly collected from one turkey parent flock, the hatchery, six different commercial turkey farms and from 11 different stages at the slaughterhouse. For the detection of Campylobacter, a conventional culture and a PCR method were used. Campylobacter isolates (n = 143) were identified to species level by a multiplex PCR assay.

Results

No Campylobacter were detected in either the samples from the turkey parent flock or from hatchery samples using the culture method. PCR detected Campylobacter DNA in five faecal samples and one fluff and eggshell sample. Six flocks out of 12 commercial turkey flocks where found negative at the farm level but only two were negative at the slaughterhouse.

Conclusion

During the brooding period Campylobacter might have contact with the birds without spreading of the contamination within the flock. Contamination of working surfaces and equipment during slaughter of a Campylobacter positive turkey flock can persist and lead to possible contamination of negative flocks even after the end of the day''s cleaning and desinfection. Reduction of contamination at farm by a high level of biosecurity control and hygiene may be one of the most efficient ways to reduce the amount of contaminated poultry meat in Finland. Due to the low numbers of Campylobacter in the Finnish turkey production chain, enrichment PCR seems to be the optimal detection method here.     

Ellipsomyxa gobii (Myxozoa: Ceratomyxidae) in the common goby Pomatoschistus microps (Teleostei: Gobiidae) uses Nereis spp. (Annelida: Polychaeta) as invertebrate hosts

Nereis diversicolor O.F. Müller and N. succinea Frey et Leuckart (Polychaeta, Nereidae) living in brackish shallow areas in Denmark are naturally infected with tetractinomyxon actinospores. Infected Nereis spp. were experimentally fed to various potential fish hosts, and the actinosporean stages developed into myxosporean stages of Ellipsomyxa gobii K?ie, 2003 (Ceratomyxidae) in the gallbladder of the common goby Pomatoschistus microps (Kr?yer) (Gobiidae). The European eel Anguilla anguilla (L.), three-spined stickleback Gasterosteus aculeatus L., small sand eel Ammodytes tobianus L., flounder Platichthys flesus (L.), European plaice Pleuronectes platessa L. and common sole Solea solea (L.) did not become experimentally infected. In Danish shallow brackish areas P. microps is naturally infected with E. gobii, in some areas with a prevalence >90%. We compared small subunit ribosomal DNA sequences of the actinosporean with E. gobii from P. microps. Sequences were identical, which further verifies that both forms belong to the same organism. This is the first myxozoan two-host life cycle in the marine environment.     

Widespread translational inhibition by plant miRNAs and siRNAs

High complementarity between plant microRNAs (miRNAs) and their messenger RNA targets is thought to cause silencing, prevalently by endonucleolytic cleavage. We have isolated Arabidopsis mutants defective in miRNA action. Their analysis provides evidence that plant miRNA-guided silencing has a widespread translational inhibitory component that is genetically separable from endonucleolytic cleavage. We further show that the same is true of silencing mediated by small interfering RNA (siRNA) populations. Translational repression is effected in part by the ARGONAUTE proteins AGO1 and AGO10. It also requires the activity of the microtubule-severing enzyme katanin, implicating cytoskeleton dynamics in miRNA action, as recently suggested from animal studies. Also as in animals, the decapping component VARICOSE (VCS)/Ge-1 is required for translational repression by miRNAs, which suggests that the underlying mechanisms in the two kingdoms are related.