Lack of Correlation Between Papillomaviral DNA in Surgical Margins and Recurrence of Equine Sarcoids

Bovine papillomavirus (BPV) types 1 (BPV-1) and 2 (BPV-2) are causally associated with the development of equine sarcoid tumors. Recurrence rates after surgical excision of sarcoids are estimated to be 30%–40%. We hypothesized that the presence of BPV DNA in histologically tumor-free surgical margins of sarcoids is associated with risk of recurrence, and increased quantity of BPV DNA is associated with increased risk of recurrence. Formalin-fixed sarcoids classified as “completely excised” histologically were obtained from two institutions. A total of 25 tumors were included, eight of which recurred within 1 year of excision. Qualitative and quantitative polymerase chain reaction (PCR) tests for detection of BPV-1 and BPV-2 were performed on neoplastic tissue and tumor-free surgical margins in formalin-fixed paraffin-embedded biopsy specimens following DNA extraction. Bovine papillomavirus-1 was found in all tumor samples and in histologically “clean” margins of 21 samples, whereas BPV-2 was found in only two tumor samples. Although quantitative PCR was more sensitive than qualitative PCR in detecting BPV DNA in surgical margins, there was no significant difference in the presence of BPV-1 or BPV-2 DNA in margins of tumors that recurred versus those that did not recur for either test. Although this study is limited by sample size, our results suggest that PCR analysis of surgical margins for BPV DNA is not a reliable method to predict equine sarcoid recurrence after resection.     

Volatile fatty acid profile for grass hay or alfalfa hay fed to alpacas (Vicugna pacos)

The purpose of this study was to determine the diurnal composition and concentration of volatile fatty acids (VFA) and to determine VFA composition and concentration differences between stomach compartment 1 (C1) and caecum of alpacas fed grass and alfalfa hay. The study was divided into two experiments. In Experiment 1 (EXP 1), 10 male alpacas (3+ years old, 65 kg BW) were divided into two groups, housed in drylot pens, provided ad libitum water and fed alfalfa (AH) or grass hay (GH) for 30 days. The alpacas were slaughtered and the digestive tract collected, divided into sub‐tract sections, weighed and digesta sampled for pH, dry matter (DM) and NDF. Volatile fatty acid composition and concentration were determined on C1 and caecal material. Four adult male (3+ years old, 60 kg BW), C1 fistulated alpacas were housed in metabolism crates and divided into two forage groups for Experiment 2 (EXP 2). Alpacas were fed the forages as in EXP 1. Diurnal C1 VFA samples were drawn at 1, 3, 6, 9, 12, 18 and 24 h post‐feeding. There were no differences between forages for tract weight, C1 and caecum digesta DM or NDF. Differences were noted (p < 0.05) for pH between forages and sub‐tract site. Volatile fatty acids concentrations were different (p < 0.05) for forage and site, and total VFA was higher for AH than GH (110.6 and 79.1 mm ) and C1 than caecum (40.7 and 27.6 mm ). Proportion of VFA was significant (p < 0.05) for forage and site, C1 acetate highest for GH (84.8 vs. 74.0 mm ) and caecum acetate 83.7 and 76.2 mm for GH and AH respectively. These data demonstrate the level of VFA produced in C1 and the caecum of alpacas and the diurnal VFA patterns. Composition of VFA is similar to other ruminant species.     

Oxygen consumption and ventilatory reflex responses are influenced by dietary lipids in sturgeon

The effects of one year's feeding with diets enriched either in highly unsaturated fatty acids of the w3 series (w3 HUFA) (fish oil-supplemented diet, FOD) or in saturated fatty acids (SFA) (coconut oil-supplemented diet, COD) on fatty acid composition of tissue lipids, on patterns of resting oxygen consumption and on responses to hypoxia and hypercapnia were investigated in the Adriatic sturgeon (Acipenser naccarii). FOD sturgeon had higher levels of w3 HUFA in liver and muscle lipids than COD fish, which had higher levels of SFA. A frequency distribution of instantaneous oxygen uptake rates (M]O2), as measured every 10 min for 8 h, revealed a different pattern of resting oxygen consumption between the two groups. The FOD sturgeon consumed oxygen in a narrow range of low rates, with a lower mean M]O2 than COD sturgeon, which showed a wide range of more elevated rates. FOD sturgeon had a lower opercular pressure amplitude than COD fish in normoxia. Exposure to three levels of hypoxia PO2s = 10.8±0.2; 6.6±0.2 and 4.6±0.2 kPa) or mild hypercapnia (PCO2 = 1.0±0.2 kPa) did not affect ventilation in FOD fish but elicited hyperventilation in COD animals. Mild hypoxia (PO2 = 10.8±0.2 kPa) and hypercapnia caused less reduction in blood oxygen content in FOD as compared with COD sturgeon. The effects of adding vitamin E supplements to the diets was investigated; groups fed vitamin E supplements had elevated M]O2 and hyperventilated in hypoxia. The data indicate that dietary fatty acid composition influences resting M]O2 in sturgeon and that this influences the regulation of ventilation and blood O2 levels in hypoxia and hypercapnia. The low resting M]O2 of fish fed w3 HUFA supplements (the FOD group) obviated the need for hyperventilation in hypoxia or hypercapnia, thereby making them less sensitive to these stresses than sturgeon fed SFA (COD group) or sturgeon fed either diet supplemented with vitamin E. This revised version was published online in July 2006 with corrections to the Cover Date.     

The influence of various confounding factors on mechanical nociceptive thresholds in the donkey

ObjectiveTo evaluate a mechanical nociceptive threshold (MNT) testing device in the donkey, and to investigate the influence of potential confounders on MNTs generated.Study designProspective, randomised.AnimalsSixteen castrated male donkeys aged 4–9 years, weighing 105–170 kg.MethodsMechanical nociceptive thresholds were measured using an actuator with three pins placed on the dorsal aspect of the distal limb, connected to a force meter. The pins (surface area 15 mm²) were extruded onto the limb by pressurising an air-filled syringe, until the MNT force (when foot-lift was observed) or 25 N (cut-off force) was reached. Effect on MNT of presence of a companion donkey, the limb tested, rate of application of force, testing location, level of distraction, ambient temperature and hair cover at the test site was evaluated. Long and short-term repeatability of MNT was assessed. Data were analysed using general linear models and Mann–Whitney U tests, p < 0.05 was considered significant.ResultsIncreasing the rate of force application significantly increased the mean ± SD MNT from 9.2 ± 2.0 N when applied at 0.4 N sec^?1 to 10.6 ± 2.1 N when applied at 1.2 N sec^?1 (p = 0.001). No other factors significantly influenced MNT. Mean MNT remained stable over a 3 week period, however MNTs were significantly (p = 0.006) higher (12.8 ± 3.0 N cf 10.3 ± 1.9 N) after a 12 month interval.Conclusions and clinical relevanceWhen designing studies measuring MNT in donkeys, rate of application of force must be standardised. Donkeys’ MNTs have good short-term stability suggesting this technique is appropriate for short-term analgesiometry studies; however variability of MNTs over the long-term is greater.     

Fatty acid composition of New Zealand green-lipped mussels, Perna canaliculus: Implications for harvesting for n-3 extracts

Marine bivalves offer a potentially important source of long-chained polyunsaturated fatty acids (PUFA) for human health supplements. Lipid extracts from individual New Zealand green-lipped mussels (NZGLM) were analyzed as fatty acid methyl esters (FAME) by gas chromatography to assess geographical and seasonal differences between large (86 ± 1 mm) male and female and small (44 ± 1 mm) mussels. PUFAs dominated in spring and summer, comprising ∼ 50% of total fatty acids. Moreover, the commercially important n-3 fatty acids, 20:5n-3 (eicosapentaenoic acid, EPA) and 22:6n-3 (docosahexaenoic acid, DHA) together accounted for 70-79% of total PUFAs in spring and summer. During winter there was a marked decrease in condition and total n-3 PUFAs and a concomitant increase in saturated fatty acids in mussels, suggesting they had already spawned, had increased metabolic demands and limited PUFA-rich phytoplankton as food. While total n-3 content was not significantly different, there were geographical differences in individual n-3 fatty acids. Mussels collected from the cooler waters of Stewart Island had greater levels of 20:5n-3 (EPA), while those collected in Marlborough had greater concentrations of 22:6n-3 (DHA), which was attributed mainly to differences in phytoplankton composition. Total n-3 content and the condition index varied seasonally with greater concentrations of n-3 PUFAs, especially EPA, recorded in large mussels in spring, coincident with spring diatom blooms. Total PUFA levels and condition indices remained high in summer. There was no significant difference in condition indices, total n-3 content, DHA or EPA levels between large male and female mussels. Conversely, large mussels had significantly greater amounts of n-3 PUFAs than small mussels at Marlborough Sounds, while small mussels had marginally greater total n-3 concentrations than large mussels at Stewart Island. Taken together, these results suggest that the NZGLM offers a potentially important source of n-3 PUFAs for human health supplements. Our findings suggest that optimal harvesting conditions occur in spring when mussel condition and n-3 content peak for large mussels. Although DHA and EPA levels varied geographically, total n-3 content was not significantly different between sites, which implies that harvesting mussels for n-3 extracts would be driven more by logistical considerations.     

Improvement of zein dough characteristics using dilute organic acids

The replacement of gluten in dough products poses a major challenge. Preparing zein doughs in dilute acetic acid and lactic acid, such as produced during sourdough fermentation, was investigated. Increasing acid concentrations (0.7, 1.3 and 5.4% [v/v]) increased zein extensibility and reduced the stress and related parameters. Preparation of zein-maize starch/-rice doughs in dilute organic acids improved dough properties to the extent that the doughs could hold air and be inflated into a bubble by Alveography. Further, they exhibited similar Stability (P), Distensibility and deformation energy (W) to wheat flour dough. Confocal laser scanning microscopy revealed an ordered linear fibril network in zein and zein-rice flour doughs prepared in the dilute acids, which became uniform with increasing acid concentration. SDS-PAGE showed that the acids did not hydrolyse or polymerise the zein. FTIR indicated that the acidic conditions slightly increased the proportion of α-helical conformation in the zein doughs, possibly as a result of deamination. This conformational change may be responsible for the considerably improved zein dough properties. Zein doughs prepared in dilute organic acids show potential as a gluten replacement in gluten-free formulations.     

Prespawn mortality in adult spring Chinook salmon outplanted above barrier dams

Keefer ML, Taylor GA, Garletts DF, Gauthier GA, Pierce TM, Caudill CC. Prespawn mortality in adult spring Chinook salmon outplanted above barrier dams.
Ecology of Freshwater Fish 2010: 19: 361–372. © 2010 John Wiley & Sons A/S Abstract – Dams without fish passage facilities block access to much of the historic spawning habitat of spring Chinook salmon (Oncorhynchus tshawytscha) in Oregon’s Willamette River basin. Adult salmon are routinely outplanted above the dams to supplement natural production, but many die before spawning despite extensive suitable habitat. In 2004–2007, we examined prespawn mortality patterns using live detection and carcass recovery data for 242 radio‐tagged outplants. Total prespawn mortality was 48%, but variability was high, ranging from 0% to 93% for individual release groups. Prespawn mortality was strongly condition dependent, consistently higher for females than males and higher for early release groups. Across years, warm water temperature in the migration corridor and at the collection site was associated with sharply higher mortality. Results highlight a need for better evaluations of the effects of adult mortality on population reintroduction and recovery and relationships among prespawn mortality, dam‐related temperature change and salmon life history and behaviour.