Knowledge and attitudes of Australian livestock producers concerning biosecurity practices

Biosecurity risks are a major threat to the profitability of the industry as well as impacting human and animal health. Livestock producers play a crucial role in biosecurity as the first to notice changes in the health or productivity of their stock and are generally responsible for implementing protective measures. However, uptake of biosecurity measures by producers is variable. We critically appraised the current literature regarding biosecurity practices in Australian livestock industries and highlight aspects that are well understood as well as those where further research or information is needed. Findings from 12 cross-sectional studies suggest that Australian producers' knowledge of biosecurity methods and importance might have a positive influence on their willingness to implement or incorporate biosecurity practices. There is moderate evidence supportive of biosecurity being well understood by livestock producers across Australia. Barriers to producers using biosecurity practices included lack of information or communication from agricultural, veterinary or government organisations. It was found that larger stock numbers were positively correlated with biosecurity implementation and that producers used veterinarians, government and industry agencies as resources for trusted information.     

Discovery of powerful gamma-ray flares from the Crab Nebula

The well-known Crab Nebula is at the center of the SN1054 supernova remnant. It consists of a rotationally powered pulsar interacting with a surrounding nebula through a relativistic particle wind. The emissions originating from the pulsar and nebula have been considered to be essentially stable. Here, we report the detection of strong gamma-ray (100 mega-electron volts to 10 giga-electron volts) flares observed by the AGILE satellite in September 2010 and October 2007. In both cases, the total gamma-ray flux increased by a factor of three compared with the non-flaring flux. The flare luminosity and short time scale favor an origin near the pulsar, and we discuss Chandra Observatory x-ray and Hubble Space Telescope optical follow-up observations of the nebula. Our observations challenge standard models of nebular emission and require power-law acceleration by shock-driven plasma wave turbulence within an approximately 1-day time scale.     

Maize Proximate Composition and Physical Properties Correlations to Dry‐Grind Ethanol Concentrations

Dry‐grind ethanol plants incur economic losses because of seasonal variations in ethanol yields. One possible cause associated with ethanol yield variability is incoming grain quality. There is little published information on factors causing variation in dry‐grind ethanol concentrations. The objective of this study was to determine relationships between rapidly measurable corn quality attributes (physical parameters and chemical composition) and dry‐grind ethanol concentrations. Corn samples obtained from a Midwestern ethanol plant were analyzed for physical quality parameters (test weight, kernel weight, true density, percent stress cracks, and moisture content) and composition (starch, protein, oil, and soluble sugars contents) and then processed with a laboratory‐scale dry‐grind procedure. There were significant (P < 0.05) variations in corn quality parameters and ethanol concentrations. Correlation coefficients were significant (P < 0.05) but low (–0.50 < r < 0.50) between starch content and final ethanol concentrations (72 h) and total soluble sugar content and ethanol concentrations at 72 and 48 h. Ethanol concentrations (at 24, 48, and 72 h) were predicted as a function of a combination of grain quality factors using multiple regression methods; however, the R² values obtained were low. Variations in ethanol concentrations were not related to physical and chemical composition quality factors. Other factors, such as structural and physiologic attributes of corn grain, need to be evaluated.     

Morphometry and abnormalities of the feet of Kaimanawa feral horses in New Zealand

Objective The present study investigated the foot health of the Kaimanawa feral horse population and tested the hypotheses that horses would have a large range of foot morphology and that the incidence of foot abnormality would be significantly high. Procedures Abnormality was defined as a variation from what the two veterinarian assessors considered as optimal morphology and which was considered to impact negatively on the structure and/or function of the foot. Fifteen morphometric variables were measured on four calibrated photographic views of all four feet of 20 adult Kaimanawa feral horses. Four morphometric variables were measured from the lateromedial radiographs of the left forefoot of each horse. In addition, the study identified the incidence of gross abnormality observed on the photographs and radiographs of all 80 feet. Results There was a large variation between horses in the morphometric dimensions, indicating an inconsistent foot type. Mean hoof variables were outside the normal range recommended by veterinarians and hoof care providers; 35% of all feet had a long toe conformation and 15% had a mediolateral imbalance. Abnormalities included lateral (85% of horses) and dorsal (90% of horses) wall flares, presence of laminar rings (80% of horses) and bull-nose tip of the distal phalanx (75% of horses). Both hypotheses were therefore accepted. Conclusions The Kaimanawa feral horse population demonstrated a broad range of foot abnormalities and we propose that one reason for the questionable foot health and conformation is lack of abrasive wearing by the environment. In comparison with other feral horse populations in Australia and America there may be less pressure on the natural selection of the foot of the Kaimanawa horses by the forgiving environment of the Kaimanawa Ranges. Contrary to popular belief, the feral horse foot type should not be used as an ideal model for the domestic horse foot.     

Extraction of pennycress (Thlaspi arvense L.) seed oil by full pressing

Pennycress is currently being developed as an oilseed crop for biofuel production. Pennycress seeds harvested from a field near Peoria, Illinois, provided our first opportunity to conduct an oil extraction study on a pilot scale. The goals of this study were to determine the effects of seed moisture and cooking on the pressing characteristics of pennycress seeds and to evaluate the quality of the oils extracted. Pennycress seeds (60 kg) with 9.5 and 16% moisture contents (MC) were cooked and dried (82–104 °C) using a steam-heated 3-deck laboratory seed cooker. The residence times were varied to produce cooked seeds with MCs ranging from 1.0 to 13.0%. The cooked seeds were pressed immediately using a heavy duty laboratory screw press. Pressing rate, press load, and residual oil in the press cakes were determined. The oils extracted were analyzed for solids content (foots), free fatty acid (FFA) content, color, and phosphorus (P), calcium (Ca), magnesium (Mg), and sulfur (S) contents. Pressing uncooked pennycress seeds with 9.5% MC produced press cake with 10.7% oil (db), extracting 75.1% of the oil in the seed. Cooking and drying the seeds between 3 and 4% MC provided the highest oil recovery at 86.3 and 88.0% for seeds with 9.5 and 16% starting seed MC, respectively. The pressing rates and press loads at these MCs were similar. Compared to the oil from uncooked seeds, the oils from cooked seeds had higher foots (1.55–1.73% vs. 0.52%), slightly higher FFA contents (0.40–0.46% vs. 0.30%), and slightly higher red values in AOCS RY color scale (4.1R–6.2R vs. 2.4R). Cooking increased the phosphatide content but the amount was still comparable to degummed oils. The sulfur levels in the expelled oil were higher than the amounts found in rapeseed oil and varied considerably depending on the seed moisture and the extent of cooking employed.     

Comparison of tramadol and morphine for pre-medication of dogs undergoing general anesthesia for orthopedic surgery

Tramadol is a centrally acting analgesic with opioid and monoaminergic actions. Its clinical effects have been well characterized in humans, where it has been in use for many years, but little is known for veterinary species. This study evaluated the sedative, emetic, thiopental‐sparing and intraoperative respiratory and hemodynamic effects of tramadol in comparison to morphine for pre‐medication of dogs undergoing orthopedic surgery under halothane anesthesia. Sixteen adult, healthy, mixed breed dogs (8.0 ± 2.6 kg) were studied. Eight dogs were pre‐medicated with tramadol (1.0 mg kg^‐1 IM) and the other eight with morphine (1.0 mg kg^–1 IM). After 20 minutes, anesthesia was induced with thiopental and subsequently maintained with halothane in oxygen using a Bain system, with spontaneous respiration. Degree of sedation and occurrence of emesis were evaluated after pre‐anesthetic medication. Dose of thiopental necessary for tracheal intubation was compared between the two groups. Arterial blood gas analyzes were done before pre‐medication and at 60 minutes of anesthesia. Heart rate and noninvasive arterial blood pressure were recorded before pre‐medication and every 10 minutes during anesthesia. Observer was blinded of the treatment given for each dog. Tramadol produced no visible sedation and no vomiting, while morphine induced a moderate degree of sedation in all dogs and vomiting in 62% of them. Dogs pre‐medicated with tramadol required significantly more thiopental (17 ± 3.8 mg kg^–1) for induction of anesthesia than those pre‐medicated with morphine (12 ± 1.8 mg kg^–1). Pre‐medication with morphine was associated with significantly higher PaCO₂ and lower pH at 60 minutes of anesthesia. The remaining respiratory parameters and the hemodynamic variables were similar between the two groups. In conclusion, dogs pre‐medicated with tramadol at 1 mg kg^–1 IM do not become visibly sedated and require a greater amount of thiopental for induction of anesthesia than pre‐medication with morphine. As intraoperative respiratory function is better preserved with tramadol, it may be useful for pre‐medication of respiratory compromised patients.     

Impact of Ultra‐Rapid Freezing on the Motility,Morphology, Viability and Acrosome Integrity of Epididymal Cat Sperm Diluted in Sucrose‐Based Extenders

The objective of the present study was to investigate the influence of different sucrose‐based extenders on the motility, morphology, viability and acrosomal integrity of epididymal cat spermatozoa cryopreserved by ultra‐rapid freezing method. Nine cats were castrated, and collected semen was diluted 1 : 1 with Dulbecco`s phosphate‐buffered saline‐BSA1%‐based extender supplemented with different sucrose concentrations (0, 0.25, 0.4 and 0.6 m ). After ultra‐rapid freezing, samples were thawed and sperm motility, morphology, viability and acrosome status were assessed. At thawing, the number of progressively motile (p < 0.01) and morphologically normal (p < 0.01) sperm was higher in the sucrose‐supplemented groups than in the sucrose‐free group. Viability of spermatozoa cryopreserved without sucrose was significantly reduced. In extender supplemented with 0.4 m sucrose, spermatozoa viability showed higher values (57.0 ± 4.7; p < 0.01). No significant differences were detected among groups for sperm acrosome integrity. Results support that cat sperm survive after ultra‐rapid freezing using sucrose as a cryoprotectant, and the best results were achieved when 0.4 m of sucrose was used. This is the first report on sperm ultra‐rapid freezing of cat sperm and further studies on extenders, sperm management or cryovials should be carried out to improve sperm cryosurvival.     

The Importance of Having Zinc During In Vitro Maturation of Cattle Cumulus–Oocyte Complex: Role of Cumulus Cells

The aim of this study was to investigate the influence of zinc (Zn) on the health of cumulus–oocyte complex (COC) during in vitro maturation (IVM). Experiments were designed to evaluate the effect of Zn added to IVM medium on: DNA integrity, apoptosis, cumulus expansion and superoxide dismutase (SOD) activity of cumulus cells (CC). Also, role of CC on Zn transport during IVM was evaluated on oocyte developmental capacity. DNA damage and early apoptosis were higher in CC matured with 0 μg/ml Zn compared with 0.7, 1.1 and 1.5 μg/ml Zn (p < 0.05). Cumulus expansion did not show differences in COC matured with or without Zn supplementation (p > 0.05). Superoxide dismutase activity was higher in COC matured with 1.5 μg/ml Zn than with 0 μg/ml Zn (p < 0.05). Cleavage and blastocyst rates were recorded after IVM in three maturation systems: intact COCs, denuded oocytes with cumulus cells monolayer (DO + CC) and denuded oocytes (DO). Cleavage rates were similar when COC, DO + CC or DO were matured with 1.5 μg/ml Zn compared with control group (p > 0.05). Blastocyst rates were significantly higher in COC than in DO + CC and DO with the addition of 1.5 μg/ml Zn during IVM (p < 0.01). Blastocyst quality was enhanced in COC and DO + CC compared with DO when Zn was added to IVM medium (p < 0.001). The results of this study indicate that Zn supplementation to IVM medium (i) decreased DNA damage and apoptosis in CC; (ii) increased SOD activity in CC; (iii) did not modify cumulus expansion and cleavage rates after in vitro fertilization; (iv) improved subsequent embryo development up to blastocyst stage; and (v) enhanced blastocyst quality when CC were present either in intact COC or in coculture during IVM.