Oat silage for grazing dairy cows in small-scale dairy systems in the highlands of central Mexico

The objective was to evaluate the provision of oat silage (Avena sativa) to supplement grazing dairy cows on pastures of perennial ryegrass (Lolium perenne), festulolium (Lolium multiflorum × Festuca pratense) and white clover (Trifolium repens) during the dry season when pasture growth is limited. The experimental design was a 3 × 3 Latin square replicated three times, with nine milking Holstein cows (mean live weight 496.2 ± 33.6 kg and daily milk yield 14.8 ± 2.8 kg cow^?1) under on-farm participatory rural research. Experimental periods were 14 d. Simulated grazing samples of pasture herbage were analysed for chemical composition, sward height recorded and net herbage accumulation determined from exclusion cages. Treatments were the inclusion of oat silage at T0 = 0 kg DM cow^?1 d^?1 of oat silage, T3 = 3 kg DM cow^?1 d^?1 of oat silage, and T6 = 6 kg DM cow^?1 d^?1 of oat silage, plus 5.0 kg fresh weight commercial concentrate and 9 h of continuous grazing. Animal variables were milk yield and composition, live weight and body condition score. Feeding costs were calculated. Mean milk yield was 18.9 ± 0.27 kg cow^?1 d^?1 with no differences in animal variables (p > 0.05), but feeding costs per kilogram milk increased 25% for T3 and 50% for T6. Oat silage supplementation is only viable under difficult grazing conditions.     

Suggested guidelines for immunohistochemical techniques in veterinary diagnostic laboratories

This document is the consensus of the American Association of Veterinary Laboratory Diagnosticians (AAVLD) Subcommittee on Standardization of Immunohistochemistry on a set of guidelines for immunohistochemistry (IHC) testing in veterinary laboratories. Immunohistochemistry is a powerful ancillary methodology frequently used in many veterinary laboratories for both diagnostic and research purposes. However, neither standardization nor validation of IHC tests has been completely achieved in veterinary medicine. This document addresses both issues. Topics covered include antibody selection, fixation, antigen retrieval, antibody incubation, antibody dilutions, tissue and reagent controls, buffers, and detection systems. The validation of an IHC test is addressed for both infectious diseases and neoplastic processes. In addition, storage and handling of IHC reagents, interpretation, quality control and assurance, and troubleshooting are also discussed. Proper standardization and validation of IHC will improve the quality of diagnostics in veterinary laboratories.     

Global phylogeography of the smooth hammerhead shark: Glacial refugia and historical migration patterns

1. Extreme climate changes during the Cenozoic Era strengthened different biogeographical barriers that decreased the connectivity among populations, triggering lineage diversification of different species worldwide.
2. The mitochondrial DNA control region was employed to explore the phylogeography of Sphyrna zygaena, a globally distributed species threatened by unsustainable, illegal, unreported and unregulated fisheries triggered by the international shark fin trade. It is listed as ‘Vulnerable’ by the IUCN Red List and its trade is regulated by CITES Appendix II.
3. Only 13 haplotypes were found with low genetic diversity levels (hd = 0.686 ± 0.014; π = 0.00206 ± 0.00004) compared with other species of the Sphyrnidae family. The species has a very strong phylogeographic population structure among the Atlantic, Indian and Pacific Oceans (Φ_ST = 0.79132). Worldwide, there are six distinct populations with some haplotype sharing.
4. These populations are probably connected by a stepping-stone dispersal of a small number of migrants per generation from the Indo-Pacific towards the Atlantic. Modelling suggests that S. zygaena diverged into two lineages around 6.96 million years ago which have been isolated in glacial refuges in the Atlantic and Indo-Pacific oceans; and after deglaciation, a population expansion probably permitted secondary contact.
5. Conservation plans to establish differentiated management units should be adopted in each of the identified populations. Among these, the Eastern Central Atlantic and West Indo-Pacific are the most important areas for the species considering the historical migration routes that act as a bridge connecting the Atlantic and Indo-Pacific Oceans while the Gulf of Guinea connects the Atlantic populations. Still, further studies are required to know if these populations are also linked with nursery areas for the species.
6. The results herein can help to delimit the main evolutionarily significant units to implement effective policies to establish differentiated management units as starting points to genetic monitoring programmes for Sphyrna zygaena.

     

Bactericidal kinetics of marine-derived napyradiomycins against contemporary methicillin-resistant Staphylococcus aureus

There is an urgent need for new antibiotics to treat hospital- and community-associated methicillin-resistant Staphylococcus aureus (MRSA) infections. Previous work has indicated that both terrestrial and marine-derived members of the napyradiomycin class possess potential anti-staphylococcal activities. These compounds are unique meroterpenoids with unusual levels of halogenation. In this paper we report the evaluation of two previously described napyradiomycin derivatives, A80915A (1) and A80915B (2) produced by the marine-derived actinomycete, Streptomyces sp. strain CNQ-525, for their specific activities against contemporary and clinically relevant MRSA. Reported are studies of the in vitro kinetics of these chemical scaffolds in time-kill MRSA assays. Both napyradiomycin derivatives demonstrate potent and rapid bactericidal activity against contemporary MRSA strains. These data may help guide future development and design of analogs of the napyradiomycins that could potentially serve as useful anti-MRSA therapeutics.     

Air Classification of Pin‐Milled Soybean Hulls

Commercial soybean hulls (14.6% crude protein) were pin milled and then air classified into five fractions to determine whether the hull structure can be disrupted and the protein constituents concentrated. The number of pin millings had only a small effect on the weight distribution of the five fractions. After one grinding, the sum of fractions 1 and 2 (<15–18 μm) represented only 3% of total hulls, and on three grindings, they amounted to only 6% of the hulls. Fraction 3 (19–24 μm) shifted from 16 to 20% with three grindings, while fraction 4 (25–30 μm) remained unchanged at 5%. Fraction 5 (>30 μm) shifted from 75 to 69% on three pin millings to compensate for the shifts noted in fractions 1–3. Scanning electron microscopy revealed that fractions 1 and 2 consisted of the parenchymal cell layers (innermost portion) of the hulls; these fractions had three times the protein content and more than twice the amount of lipids found in the ground starting material. Fraction 3 contained many of the hourglass cells typically found in the middle layer of the hulls plus parenchyma cell material and exhibited about twice the amount of protein and lipid found in the starting hulls. Fraction 4 included large hourglass cells plus globular material and contained about twice the amount of protein and about one and one‐half times the lipid of the starting material. Fraction 5 consisted primarily of clumps of palisade cells (outer cellular layer) adhering to each other and had a lower protein and lipid content than the starting hulls. Thus, pin milling causes some selective disruption of the hulls where parenchyma cell layers and hourglass cells are partially released. The palisade cells, however, are the most difficult to disrupt and constitute the fraction most resistant to pin milling. Our findings suggest that pin milling soybean hulls in combination with air classification can be used to concentrate the proteins and lipids in the fines fractions.     

Serum C-reactive protein and iron levels following gonadectomy are not modified by perioperative administration of robenacoxib to dogs

The aim of this study was to evaluate the perioperative effects of robenacoxib on serum C-reactive protein (CRP) and iron concentrations in dogs undergoing gonadectomy. In a prospective, blinded, controlled clinical trial, 60 healthy dogs were randomly assigned to receive preoperative subcutaneous injection of either robenacoxib [2 mg/kg body weight (BW)], meloxicam (0.2 mg/kg BW), or saline (0.04 mL/kg BW), followed by oral administration over 72 h (robenacoxib: 2 to 4 mg/kg BW; meloxicam: 0.1 mg/kg BW; saline: gelatin capsules). Blood samples were taken before surgery and 12, 24, 48, 72 h, and 7 d after surgery. Pain scores were assessed via the short-form Glasgow Composite Pain Scale over 72 h postoperatively. C-reactive protein (CRP) and iron serum levels increased and decreased (P < 0.01, both), respectively, after surgery and returned to baseline within 1 wk. No differences were observed among treatments (P > 0.05) or based on surgery/gender (P > 0.05). Pain assessment revealed a higher incidence of treatment failure in saline (6 females versus 2 and 1 female in robenacoxib and meloxicam, respectively). In conclusion, robenacoxib and meloxicam had no influence on postoperative CRP or iron in dogs, which suggests that these nonsteroidal anti-inflammatory drugs (NSAIDs) do not have a relevant effect on these biomarkers.     

In vitro predatory activity of nematophagous fungi <Emphasis Type="Italic">Duddingtonia flagrans</Emphasis> on infective larvae of <Emphasis Type="Italic">Oesophagostomum</Emphasis> spp. after passing through gastrointestinal tract of pigs

One isolate of predator fungi Duddingtonia flagrans (AC001) was assessed in vitro regarding the capacity of supporting the passage through pigs' gastrointestinal tract without loss of the ability of preying infective larvae Oesophagostomum spp. Fungal isolates survived the passage and were efficient in preying L₃ since the first 8 h of collection (p < 0.01) in relation to the control group (without fungus). Compared with control, there was a significant decrease (p < 0.01) of 59.6% (8 h), 71.7% (12 h), 76.8% (24 h), 81.0% (36 h), 78.0% (48 h), 76.1% (72 h), and 82.7% (96 h) in means of infective larvae Oesophagostomum spp. recovered from treatments with isolate AC001. Linear regression coefficients of L₃ of recovered Oesophagostomum spp. regarding the collections due to time were −0.621 for control, −1.40 for AC001, and −2.64 for NF34. Fungi D. flagrans (AC001) had demonstrated to be promising for use in the biological control of pig parasite Oesophagostomum spp.